- Email: [email protected]
Outcomes of hysterectomies performed by supervised residents vs those performed by attendings alone
SGS Papers
www. AJOG.org
Outcomes of hysterectomies performed by supervised residents vs those performed by attendings alone Danita H. Akingba, MD; Tatiana V. Deniseiko-Sanses, MD; Clifford F. Melick, PhD; R. Mark Ellerkmann, MD; Koji Matsuo, MD OBJECTIVE: The objective of the study was to compare the outcomes
of hysterectomies performed by residents under supervision of a teaching physician with those performed by attendings alone. STUDY DESIGN: This was a retrospective cohort analysis of hysterectomies performed at the Greater Baltimore Medical Center from 2004 to 2006.
⫽ .005), seromas (2.5% vs 0%; P ⫽ .02), and others (5% vs 0.8%; P ⫽ .007) in nonteaching vs teaching cases, respectively. The demographics and comorbidities were similar. The mean operating room time difference of 13 minutes was not clinically significant. CONCLUSION: Although teaching hysterectomies take a bit longer to
perform, there were no greater adverse outcomes.
RESULTS: Of 159 nonteaching and 265 teaching cases, there was no
significant difference in any of the surgical outcomes, except mean operating room time in minutes (94.8 [⫾ 47.0] vs 107.4 [⫾ 42.4]; P
Key words: hysterectomies, operating room time, residents under supervision, teaching physician
Cite this article as: Akingba DH, Deniseiko-Sanses TV, Melick CF, et al. Outcomes of hysterectomies performed by supervised residents vs those performed by attendings alone. Am J Obstet Gynecol 2008;199:673.e1-673.e6.
H
ysterectomy is the second most commonly performed surgical procedure by gynecologists, after cesarean section, for women of reproductive age in the United States. From 1994 to 1999, more than 3.5 million hysterectomies were performed for women over the age of 15 years, and approximately 600,000 hysterectomies are performed annually in the United States.1 Most hysterectomies are performed for benign disease. Uterine leiomyoma, endometriosis, and uterine prolapse were the most From the Division of Urogynecology, Department of Gynecology, Greater Baltimore Medical Center, Towson, MD (Drs Akingba, Deniseiko-Sanses, and Ellerkmann); the Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (Dr Melick); and the Department of Obstetrics and Gynecology, University of Maryland School of Medicine (Dr Matsuo), Baltimore, MD. Presented at the 34th Annual Scientific Meeting of the Society of Gynecologic Surgeons, Savannah, GA, April 14-16, 2008. Received Jan. 15, 2008; revised May 19, 2008; accepted July 21, 2008. Reprints not available from the authors. 0002-9378/$34.00 © 2008 Mosby, Inc. All rights reserved. doi: 10.1016/j.ajog.2008.07.052
frequent diagnoses for women undergoing hysterectomy and accounted for 73% of all hysterectomies during 1994-1999. Given the numerous indications for hysterectomy, it is paramount that obstetrics and gynecology residents gain proficiency in this procedure during the 4 years of residency training in this specialty. We performed a literature search on PubMed and OVID, from 1950 to the present, but found no articles reporting on hysterectomy outcomes when performed with and without residents as teaching and nonteaching cases. It is generally accepted that there is a learning curve when any new surgical technique is acquired. It is also assumed that a greater percentage of adverse outcomes are tied to surgical inexperience and/or low caseload. The percentage of adverse outcomes that occur while learning a new surgical procedure has been reported in the literature. For example, Abouassaly et al2 reported on the learning curve for TVT midurethral sling procedures in which they found a greater number of bladder perforations occurring during the first 7-10 tension-free vaginal tape (TVT) procedures performed. In another case series, evaluating the learning curve of midurethral slings, as many as 37% of incidental cystotomies were missed by the resident
performing a TVT with a trained and experienced urogynecologist scrubbed in and supervising the procedure.3 Many physicians and patients question the role of residents during surgery. In some cases, residents are intentionally excluded from surgery.4 The reasons for this are often multifactorial but often include the perception on the part of the attending physician or patient that resident involvement in a case may be detrimental to the patient. The perception of detrimental care, either with regard to a perceived higher complication rate or substandard surgical performance, may or may not be legitimate. Often it is based on the attending physician’s personal experience, lack of confidence in the resident’s surgical competence, or the patient’s misconception of the resident’s actual role during surgery. The goal of this research project was to address these concerns in an objective manner, specifically with regard to complication rates. The primary objective of this study was to compare the complication rate for hysterectomies in teaching cases with those of nonteaching cases. Our secondary objective was to show whether there is a learning curve based on experience in performing hysterectomies.
DECEMBER 2008 American Journal of Obstetrics & Gynecology
673.e1
SGS Papers M ATERIALS AND M ETHODS Greater Baltimore Medical Center is a private hospital in a suburb of Baltimore, MD. Its faculty is mostly comprised of private practice obstetrics/gynecology groups. It supports a 3-year urogynecology fellowship. Johns Hopkins obstetrics/gynecology residents rotate through the hospital for general gynecology services and gynecologic oncology services. In addition, Johns Hopkins gynecologic oncology fellows rotate through the gynecologic oncology service. Institutional review board approval was obtained to abstract data from all patients who underwent a hysterectomy at the Greater Baltimore Medical Center between October 2004 and October 2006. We performed a retrospective chart analysis of all hysterectomy cases performed at our institution during this 2-year period. Using all of the 2005 hysterectomy Current Procedural Terminology codes, the medical records department generated a list of charts in order by medical record number. A list totaling 886 patients was generated. We abstracted the data sequentially by medical record number until we reached the number of charts needed for adequate power, as predetermined by statistical analysis. A total of 424 patients fit all of the inclusion criteria. We included all hysterectomies, with or without concurrent removal of adnexa (total abdominal, supracervical abdominal, vaginal, laparoscopic assisted vaginal, laparoscopic supracervical, and total laparoscopic hysterectomies), that were performed emergently or electively for benign disease. We excluded all gynecologic oncology cases, because all of theses cases had a resident and/or fellow assistant, and, as such, there were no nonteaching cases for comparison. Additionally, we presumed there would be greater blood loss and other adverse outcomes in this group of patients that could potentially bias our results. Patients were allocated to 1 of 2 groups: 1 in which there was a resident involved in the surgery and 1 in which there was not. All of the patients were initially seen, assessed, and consented by 673.e2
www.AJOG.org an attending surgeon. In 1 group (nonteaching group), the patient’s attending physician and his or her partner performed the operation. In the second group (teaching group), the attending operated on his or her patient with a resident or fellow assisting. The surgical outcomes that were measured included operating room (OR) time, a change in pre- and postsurgical hematocrit (HCT), estimated blood loss (EBL), and other perioperative complications. The data were abstracted using a predetermined Excel spreadsheet (Microsoft Corp, Redmond, WA) and entered directly in the computer database for later analysis. Three power analyses were performed, based on null hypotheses specifying clinical equivalence in mean OR time, change in mean pre- to postsurgical HCT levels, and mean EBL for teaching vs nonteaching cases to ensure that a sufficient number of charts were reviewed to achieve adequate statistical power. With respect to operative time, our null hypothesis was that the mean OR time was 20 minutes longer for teaching cases than for nonteaching cases (our definition of clinical equivalence). Given a power of 80% to reject this null hypothesis and an average OR time for nonteaching cases of 95 minutes, we assumed a 20% difference would be clin-
ically significant. With an alpha (1 tailed) set at 0.05, the required sample size for each group was 69. With respect to change in HCT, our null hypothesis was that the postoperative HCT would be 6 percentage points lower for teaching cases than for nonteaching cases (our definition of clinical equivalence). Again, we assigned a power of 80% to reject this null hypothesis. The mean postoperative HCT for nonteaching cases was 31.8% (estimated from our nonteaching sample of cases). Assuming that a 20% difference would be clinically significant and with alpha (1 tailed) set at 0.05, the required sample size for each of the 2 groups was 57. Finally, with respect to EBL, our null hypothesis was that the mean EBL for teaching cases is 150 mL higher (our definition of clinical equivalence) than the mean for nonteaching cases. Again, an 80% power to reject this null hypothesis was assigned. The mean EBL from our nonteaching cases was 280 mL. Assuming a 50% difference to be clinically significant, and with an alpha (1 tailed) set at 0.05, the required sample size for each of the 2 groups was 58 per group. Originally, we stratified the hysterectomy groups into abdominal, vaginal, and laparoscopic hysterectomies to determine whether there are more compli-
TABLE 1
Demographics Demographics
Nonteaching cases
Teaching cases
P value
Type of hysterectomy
.....................................................................................................................................................................................................................................
Abdominal, % (n)
61.0 (97/159)
62.3 (165/265)
.76
Vaginal, % (n)
17.6 (28/159)
24.2 (64/265)
.14
Laparoscopic, % (n)
21.4 (34/159)
13.6 (36/265)
.04
45.8 (⫾ 7.7)
47.5 (⫾ 10.4)
.07
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
Mean age, y (⫾ SD)
..............................................................................................................................................................................................................................................
Race
.....................................................................................................................................................................................................................................
Asian, % (n)
.6 (1/159)
.8 (2/262)
1.00
Black, % (n)
25.2 (40/159)
34.7 (91/262)
.05
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
Hispanic, % (n)
0.0 (0/159)
.8 (2/262)
.53
White, % (n)
74.2 (118/159)
62.2 (163/262)
.01
Other, % (n)
0.0 (0/159)
1.5 (4/262)
.30
Mean BMI (⫾ SD)
28.6 (⫾ 6.9)
29.3 (⫾ 6.1)
.29
Mean preoperative HCT (⫾ SD)
38.0 (⫾ 3.9)
37.5 (⫾ 4.4)
.32
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
American Journal of Obstetrics & Gynecology DECEMBER 2008
SGS Papers
www.AJOG.org
TABLE 2
Risk factors and comorbidities Comorbidity Diabetes, % (n)
Nonteaching cases
Teaching cases
P value
2.5 (4/158)
6.8 (18/264)
.070
Hypertension, % (n)
28.5 (45/158)
31.1 (82/264)
.59
Coronary artery disease, % (n)
11.4 (18/158)
14.4 (38/264)
.46
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Cerebrovascular accident, % (n)
0.0 (0/158)
1.5 (4/264)
.30
Anemia, % (n)
17.0 (27/159)
15.5 (41/265)
.68
Myomas, % (n)
51.6 (82/159)
38.9 (103/265)
.01
Menorrhagia, % (n)
57.2 (91/159)
51.3 (136/265)
.27
Adnexal mass, % (n)
11.3 (18/159)
14.8 (39/264)
.38
Tobacco use, % (n)
16.4 (24/146)
26.0 (67/258)
.04
1.3 (2/149)
1.2 (3/260)
1.00
19.6 (31/158)
13.2 (35/265)
.10
Postmenopausal bleeding, % (n)
3.8 (6/158)
3.4 (9/265)
.79
Neoplasia, % (n)
1.3 (2/159)
3.0 (8/265)
.33
Pelvic organ prolapse, % (n)
8.8 (14/159)
15.8 (42/265)
.04
Stress urinary incontinence, % (n)
6.9 (11/159)
7.5 (20/265)
.85
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Alcoholism, % (n)
and nonteaching cases (n ⫽ 159), thereby exceeding the number of cases in each group required to power the study to the requisite 80% level. Differences in teaching vs nonteaching cases were assessed using the Pearson 2 test for interval variables and Fisher’s exact test for nominal categories. Differences in means were examined using the independent samples t-test, with separate or pooled variance estimates, depending on the results of the Levine test for equality of variances of the 2 groups. Analyses were performed using SPSS 15.0 software (SPSS, Inc, Chicago, IL).
..............................................................................................................................................................................................................................................
Dysmenorrhea, % (n)
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Chronic pelvic pain, % (n)
12.7 (20/157)
7.5 (20/265)
.09
Psychological indications, % (n)
1.3 (2/159)
3.0 (8/265)
.33
Mean number of other comorbidities (⫾ SD)
1.3 (⫾ 1.1)
1.3 (⫾ 1.3)
.77
.............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
cations with the newer minimally invasive techniques, compared with traditional hysterectomies. After data analysis we found no significant difference
between laparoscopic, vaginal, and open hysterectomies. We therefore combined all types of hysterectomy and separated the total number into teaching (n ⫽ 265)
R ESULTS A total of 424 patients were included in this study. The demographics and comorbidities are summarized in Table 1. There was an overall significant difference in race between the 2 groups, with more nonwhites in the teaching vs the nonteaching groups. Teaching cases tended to have more African Americans in them, which approached statistical significance (25.2% vs 34.7%; P ⫽ .051). Whites accounted for a statistically significantly larger portion of cases in the nonteaching group (74.2% vs 62.2%; P ⫽ .014). The nonteaching group also had a statistically significantly larger proportion
TABLE 3
Surgical outcomes Outcome
Teaching cases
P value
94.8 (⫾ 47.0)
107.4 (⫾ 42.4)
.005
1.5 (⫾ 1.2)
1.3 (⫾ 1.1)
.12
Supracervical hysterectomy, % (n)
17.6 (23/131)
17.5 (35/200)
1.00
Total hysterectomy, % (n)
82.4 (108/131)
81.5 (163/200)
.89
272.0 (⫾ 280.0)
242.7 (⫾ 204.1)
.22
31.78 (⫾ 4.2)
32.1 (⫾ 4.1)
.49
Mean OR time, min (⫾ SD)
Nonteaching cases
................................................................................................................................................................................................................................................................................................................................................................................
Mean number of concurrent surgeries (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................
Mean EBL, mL (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................
Mean postoperative HCT (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................
Mean attending surgeon experience, y (⫾ SD)
25.1 (⫾ 5.1)
21.3 (⫾ 8.6)
.00
Adenomyosis, % (n)
42.1 (67/159)
38.9 (103/265)
.54
Endometriosis, % (n)
12.6 (20/159)
11.0 (29/264)
.64
Leiomyoma, % (n)
69.8 (111/159)
70.9 (188/265)
.83
264.3 (⫾ 301.1)
288.1 (⫾ 375.7)
.5
................................................................................................................................................................................................................................................................................................................................................................................ a ................................................................................................................................................................................................................................................................................................................................................................................ a ................................................................................................................................................................................................................................................................................................................................................................................ a ................................................................................................................................................................................................................................................................................................................................................................................
Mean uterine weight, g (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................ a
By pathology.
................................................................................................................................................................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
DECEMBER 2008 American Journal of Obstetrics & Gynecology
673.e3
SGS Papers
www.AJOG.org
TABLE 4
Adverse outcomes and complications Complication Transfusion, % (n)
Nonteaching cases
Teaching cases
P value
4.4 (7/158)
4.2 (11/261)
1.00
22.0 (35/159)
16.7 (44/263)
.2
Wound infection, % (n)
3.1 (5/159)
1.9 (5/263)
.51
Wound sepsis/dehiscence, % (n)
1.9 (3/159)
0.4 (1/263)
.15
Seroma, % (n)
2.5 (4/159)
0.0 (0/263)
.02
Abcess, % (n)
1.9 (3/158)
1.1 (3/263)
.68
Ileus, % (n)
3.8 (6/159)
1.9 (5/263)
.34
Readmission to hospital, % (n)
8.8 (14/159)
7.2 (19/263)
.58
Return to OR, % (n)
2.5 (4/159)
2.7 (7/263)
1.00
Atelectasis, % (n)
4.4 (7/159)
7.2 (19/263)
.3
Pneumonia, % (n)
1.3 (2/159)
0.4 (1/263)
.56
Cystitis, % (n)
2.5 (4/159)
2.7 (7/263)
1.00
Injury to viscous, % (n)
1.3 (2/159)
1.9 (5/263)
.72
Ureteral injury, % (n)
0.0 (0/159)
0.4 (1/265)
1.00
Cystotomy, % (n)
1.9 (3/159)
1.5 (4/265)
1.00
SBO, % (n)
2.1 (2/97)
3.0 (5/165)
1.00
Hematoma, % (n)
1.6 (2/125)
1.3 (3/229)
1.00
Fistula, % (n)
0.0 (0/28)
1.6 (1/64)
1.00
Nerve injury, % (n)
0.0 (0/28)
1.6 (1/64)
1.00
Thromboembolism, % (n)
1.0 (1/97)
1.2 (2/165)
1.00
Urinary retention, % (n)
3.1 (5/159)
3.4 (9/265)
1.00
30.2 (48/159)
30.2 (79/262)
1.00
5.0 (8/159)
0.8 (2/265)
.01
..............................................................................................................................................................................................................................................
Fever, % (n)
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Adhesions, % (n)
.............................................................................................................................................................................................................................................. a
Other, % (n)
.............................................................................................................................................................................................................................................. a
Other complications: hip sprain, lost laparotomy sponge, readmission for gastroenteritis, a chest wall abscess at the site of concurrent skin tag removal, syncope, and peritonitis.
..............................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
of laparoscopic hysterectomies (21.4% vs 13.6%; P ⫽ .042). The mean body mass index (kilograms per square meter), mean age, and preoperative hematocrit were similar between the 2 groups. The risk factors and comorbidities for the 2 groups are summarized in Table 2. The nonteaching groups were more likely to have a preoperative diagnosis for leiomyomata uteri (51.6% vs 38.9%; P ⫽ .012) and less likely to be smokers (16.4% vs 26.0%; P ⫽ .035). However, when the data were analyzed for uterine size and pathological confirmation of leiomyomas, there was no difference between the 2 groups (Table 3). Table 3 summarizes the surgical outcomes for our study. There was no statis673.e4
tically significant difference between the 2 groups for 2 major outcomes measured, such as mean EBL (milliliters) (272.0 ⫾ 280 vs 242.2 ⫾ 204.1; P ⫽ .220) and postoperative HTC (percent) (31.78 ⫾ 4.2 vs 32.1 ⫾ 4.1; P ⫽ .49). The OR time difference in minutes was 94.8 ⫾ 47.0 vs 107.4 ⫾ 42.4; P ⫽ .005 in the nonteaching vs teaching groups, respectively. The mean number of concurrent surgeries (1.5 ⫾ 1.2 vs 1.3 ⫾ 1.1; P ⫽ .12) and percent of supracervical hysterectomies (17.6% vs 17.5%; P ⫽ 1.00) were similar in nonteaching and teaching groups, respectively. Teaching cases were more likely performed by attendings with less years of experience (21.3 ⫾ 8.6 vs 25.1 ⫾ 5.1; P ⫽ .00).
American Journal of Obstetrics & Gynecology DECEMBER 2008
We also examined the data for the adverse outcomes that are listed in Table 4. There was a statistically significantly higher incidence of seromas (2.5% vs 0.0%; P ⫽ .02) and “other miscellaneous adverse outcomes” (5.0% vs 0.8%; P ⫽ .007) seen between the 2 types of cases. Other miscellaneous adverse outcomes were a hip sprain, lost laparotomy sponge, readmission for gastroenteritis, a chest wall abscess at the site of concurrent skin tag removal, syncope, and peritonitis. There was no significant difference in all other complications studied in both groups. Bivariate analysis was used to look for trends based on years of surgical experience (Table 5). There was no correlation between the residents’ levels of postgraduate training (postgraduate year level) and EBL, OR time, or postoperative HCT. For nonteaching cases, there was a moderate inverse linear relationship between the attending surgeons’ years of experience and OR time (r ⫽ -0.314; P ⬍ .001). For teaching cases, there was a moderate inverse linear relationship between the fellow surgeon’s years of experience and EBL (r ⫽ -0 .278; P ⫽ .023). Similar correlations were observed when all 424 cases were analyzed (Table 6). Additionally, there is a slight inverse linear relationship between the attending surgeons’ years of experience and postoperative HCT level (r ⫽ -0.102; P ⫽ .038).
C OMMENT To our knowledge, this is the first study that compares outcomes for hysterectomies involving obstetrics/gynecology residents, compared with those performed solely by attending physicians. Others have examined outcomes of teaching other types of gynecological surgery. Similarly, these authors have found no significant differences in adverse outcomes between teaching and nonteaching cases.2,3,5-7 The results of our study indicate some interesting trends. Teaching hysterectomies warrant more time. The need for added time to complete a hysterectomy goes beyond the 4 years of an obstetrics-gynecology
SGS Papers
www.AJOG.org
TABLE 5
Analysis of surgical experience and outcomes in nonteaching and teaching groups OR time
EBL
Postoperative HCT
Nonteaching group
.......................................................................................................................................................................................................................................................................................................................................................................
Attending surgeons’ years of experience
Pearson correlation
-0.314
-0.072
-0.099
0.000
0.376
0.220
.....................................................................................................................................................................................................................................
Significance (2 tailed)
................................................................................................................................................................................................................................................................................................................................................................................
Teaching group
.......................................................................................................................................................................................................................................................................................................................................................................
Attending surgeons’ years of experience
Pearson correlation
-0.10
0.04
-0.10
Significance (2 tailed)
0.11
0.49
0.11
Pearson correlation
0.002
0.02
0.07
Significance (2 tailed)
0.98
0.82
0.31
Pearson correlation
0.12
-0.28
0.22
Significance (2 tailed)
0.33
0.02
0.08
.....................................................................................................................................................................................................................................
.......................................................................................................................................................................................................................................................................................................................................................................
Resident surgeons’ years of experience
.....................................................................................................................................................................................................................................
.......................................................................................................................................................................................................................................................................................................................................................................
Fellow surgeons’ years of experience
.....................................................................................................................................................................................................................................
................................................................................................................................................................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
residency well into the years of practice as an obstetrics/gynecology attending. However, this added time needed to perform surgery might be well balanced by less blood loss and other adverse events such as seroma formation. Surprisingly, no trend or association was seen between the residents’ levels of postgraduate training (postgraduate year level) and the 3 major outcome variables measured in this study. However, we did find that as the urogynecology fellows’ years of experience increased, EBL tended to decrease. We speculated this trend might have been unmasked because the fellows were probably given more independence while operating than the residents, regardless of their number of years of training. When we examined associations between years of experience for the attendings, some interesting results were found. The surgical groups with less ex-
perienced attendings (based on the number of years following residency training) took longer to operate than more experienced attendings. However, less experienced attendings tended to have patients with higher postoperative hematocrits. This trend implies that less experienced attendings are more likely to operate more slowly and more cautiously than more experienced attendings. This may be because the less experienced attendings were more likely to be involved in a teaching hysterectomy, which inherently warrants more caution and time. It is unclear from reviewing the patients’ charts which criteria were used by the surgical attending to decide whether a resident or his or her partner were to assist in a given case. We also noticed a trend away from teaching as obstetricsgynecology attendings gained years of experience and when newer techniques
were used. This was surprising, but there might be several plausible explanations. First, older attendings may have been more likely to have been involved in litigation in the past and thus may shy away from the perceived risk of teaching. Second, they may be under greater financial pressure to perform a case quickly to return to a busy office practice. Third, being farther from their residency training may lead to a sense of insecurity regarding their skill level with newer ways of performing hysterectomies. We have a 3-year fellowship in urogynecology at Greater Baltimore Medical Center. The faculty members in this program are actively involved with resident/ fellowship education. Therefore, we expected to have a higher percentage of patients with pelvic organ prolapse in the teaching group. The nonteaching group was more likely to have a preoperative diagnosis for fibroids. We are not sure
TABLE 6
Analysis of surgical experience and outcomes in all cases Surgical experience Attending surgeons’ years of experience
OR time Pearson correlation
EBL
Postoperative HCT
-0.18
0.02
-0.10
0.00
0.70
0.04
...........................................................................................................................................................................................................................................
Significance (2 tailed)
................................................................................................................................................................................................................................................................................................................................................................................
Resident surgeons’ years of experience
Pearson correlation
0.002
0.02
0.07
Significance (2 tailed)
0.98
0.82
0.31
Pearson correlation
0.12
-0.28
0.22
Significance (2 tailed)
0.33
0.02
0.08
...........................................................................................................................................................................................................................................
................................................................................................................................................................................................................................................................................................................................................................................
Fellow surgeons’ years of experience
...........................................................................................................................................................................................................................................
................................................................................................................................................................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
DECEMBER 2008 American Journal of Obstetrics & Gynecology
673.e5
SGS Papers why this is, although one could speculate that these attendings may have excluded residents from cases they felt would be more technically challenging. There were significantly more seromas and other miscellaneous adverse outcomes in the nonteaching hysterectomy cases. It is entirely possible that there were some seromas seen in the office that were not readmitted, falsely skewing the statistical significance for this result. Because of time and budget constraints, we were limited to reviewing hospital charts for all of the patients in this study. This would limit our ability to detect seromas and wound infections that were handled on an outpatient basis by the various private practices that operate at Greater Baltimore Medical Center. We also saw a significant difference in “other miscellaneous complications.” These included hip sprain, lost laparotomy sponge, readmission for gastroenteritis, a chest wall abscess at the site of concurrent skin tag removal, syncope, and peritonitis. We were not adequately powered to detect a difference in any of these variables. To detect a 20% difference in these rare outcomes, our initial power analyses determined that we would need 21,000 people in each group. We collected data on these variables to look for trends that could be used in a future metaanalysis. Teaching cases tended to have more African Americans, a demographic finding that approached statistical significance, and more nonwhites, which did
673.e6
www.AJOG.org reach statistical significance. With no direct measure for socioeconomic status between the 2 groups in our review, perhaps this may point to a greater trend among more affluent patients to exclude residents from their surgeries. We have no explanation why nonteaching cases tended to have more nonsmokers. Limitations of our study obviously include its retrospective design and access to only hospital charts. The degree of residents’ and fellows’ participation in teaching cases is hard to determine from the hospital records. Was the resident/ fellow a surgeon who performed more than 50% of the case or just an assistant who mostly observed it? Based on our knowledge about general practices by different attendings in our institution, we assumed that all the residents/fellows were active participants in performing hysterectomy and therefore could affect the hysterectomy outcomes. Despite these limitations, our data strongly support the conclusion that teaching hysterectomies are as safe as nonteaching hysterectomies when performed under the guidance of competent attending surgeons. Given the time and expense of a prospective study, coupled with the apparent bias on the part of the public, recruiting patients for such a study might prove difficult, if not improbable. Some unanswered questions include what basis the attendings in our study used to decide whether to perform the surgeries alone or with a resident, why
American Journal of Obstetrics & Gynecology DECEMBER 2008
older attendings tended to exclude residents from their cases, why patients who smoked tended to undergo teaching hysterectomies, and whether race is a factor for excluding or allowing residents to be included in a hysterectomy. We propose that a national database could be used to look at health disparities and attitudes about teaching surgery cases to see whether lower socioeconomic status, race, and overall health of a patient are deciding factors for allowing f student surgeons to operate. REFERENCES 1. Keshavarz H, Hillis SD, Kieke BA, et al. Hysterectomy surveillance—United States, 19941999. WWMR CDC Surveill Summ 2002;51: 1-8. 2. Abouassaly R, Steinberg JR, Lemieux M, et al. Complications of tension-free vaginal tape surgery: a multi-institutional review. BJU Int 2004;94:110-3. 3. McLennan MT, Melick CF. Bladder perforation during tension-free vaginal tape procedures: Analysis of learning curve and risk factors. Obstet Gynecol 2005;106:1000-4. 4. Kim HN, Gates E, Lo B. What hysterectomy patients want to know about the roles of residents and medical students in their care. Acad Med 1998;73:339-41. 5. Shaked A, Calderom I, Durst A. Safety of surgical procedures performed by residents. Arch Surg 1991;126:559-60. 6. Coates KW, Kuehl TJ, Bachofen CG, Shull BL. Analysis of surgical complications and patient outcomes in a residency training program. Am J Obstet Gynecol 2001;184:1380-3. 7. Sorosky JI, Anderson B. Surgical experiences and training of residents: perspective of experienced gynecologic oncologists. Gynecol Oncol 1999;75:222-3.
www. AJOG.org
Outcomes of hysterectomies performed by supervised residents vs those performed by attendings alone Danita H. Akingba, MD; Tatiana V. Deniseiko-Sanses, MD; Clifford F. Melick, PhD; R. Mark Ellerkmann, MD; Koji Matsuo, MD OBJECTIVE: The objective of the study was to compare the outcomes
of hysterectomies performed by residents under supervision of a teaching physician with those performed by attendings alone. STUDY DESIGN: This was a retrospective cohort analysis of hysterectomies performed at the Greater Baltimore Medical Center from 2004 to 2006.
⫽ .005), seromas (2.5% vs 0%; P ⫽ .02), and others (5% vs 0.8%; P ⫽ .007) in nonteaching vs teaching cases, respectively. The demographics and comorbidities were similar. The mean operating room time difference of 13 minutes was not clinically significant. CONCLUSION: Although teaching hysterectomies take a bit longer to
perform, there were no greater adverse outcomes.
RESULTS: Of 159 nonteaching and 265 teaching cases, there was no
significant difference in any of the surgical outcomes, except mean operating room time in minutes (94.8 [⫾ 47.0] vs 107.4 [⫾ 42.4]; P
Key words: hysterectomies, operating room time, residents under supervision, teaching physician
Cite this article as: Akingba DH, Deniseiko-Sanses TV, Melick CF, et al. Outcomes of hysterectomies performed by supervised residents vs those performed by attendings alone. Am J Obstet Gynecol 2008;199:673.e1-673.e6.
H
ysterectomy is the second most commonly performed surgical procedure by gynecologists, after cesarean section, for women of reproductive age in the United States. From 1994 to 1999, more than 3.5 million hysterectomies were performed for women over the age of 15 years, and approximately 600,000 hysterectomies are performed annually in the United States.1 Most hysterectomies are performed for benign disease. Uterine leiomyoma, endometriosis, and uterine prolapse were the most From the Division of Urogynecology, Department of Gynecology, Greater Baltimore Medical Center, Towson, MD (Drs Akingba, Deniseiko-Sanses, and Ellerkmann); the Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (Dr Melick); and the Department of Obstetrics and Gynecology, University of Maryland School of Medicine (Dr Matsuo), Baltimore, MD. Presented at the 34th Annual Scientific Meeting of the Society of Gynecologic Surgeons, Savannah, GA, April 14-16, 2008. Received Jan. 15, 2008; revised May 19, 2008; accepted July 21, 2008. Reprints not available from the authors. 0002-9378/$34.00 © 2008 Mosby, Inc. All rights reserved. doi: 10.1016/j.ajog.2008.07.052
frequent diagnoses for women undergoing hysterectomy and accounted for 73% of all hysterectomies during 1994-1999. Given the numerous indications for hysterectomy, it is paramount that obstetrics and gynecology residents gain proficiency in this procedure during the 4 years of residency training in this specialty. We performed a literature search on PubMed and OVID, from 1950 to the present, but found no articles reporting on hysterectomy outcomes when performed with and without residents as teaching and nonteaching cases. It is generally accepted that there is a learning curve when any new surgical technique is acquired. It is also assumed that a greater percentage of adverse outcomes are tied to surgical inexperience and/or low caseload. The percentage of adverse outcomes that occur while learning a new surgical procedure has been reported in the literature. For example, Abouassaly et al2 reported on the learning curve for TVT midurethral sling procedures in which they found a greater number of bladder perforations occurring during the first 7-10 tension-free vaginal tape (TVT) procedures performed. In another case series, evaluating the learning curve of midurethral slings, as many as 37% of incidental cystotomies were missed by the resident
performing a TVT with a trained and experienced urogynecologist scrubbed in and supervising the procedure.3 Many physicians and patients question the role of residents during surgery. In some cases, residents are intentionally excluded from surgery.4 The reasons for this are often multifactorial but often include the perception on the part of the attending physician or patient that resident involvement in a case may be detrimental to the patient. The perception of detrimental care, either with regard to a perceived higher complication rate or substandard surgical performance, may or may not be legitimate. Often it is based on the attending physician’s personal experience, lack of confidence in the resident’s surgical competence, or the patient’s misconception of the resident’s actual role during surgery. The goal of this research project was to address these concerns in an objective manner, specifically with regard to complication rates. The primary objective of this study was to compare the complication rate for hysterectomies in teaching cases with those of nonteaching cases. Our secondary objective was to show whether there is a learning curve based on experience in performing hysterectomies.
DECEMBER 2008 American Journal of Obstetrics & Gynecology
673.e1
SGS Papers M ATERIALS AND M ETHODS Greater Baltimore Medical Center is a private hospital in a suburb of Baltimore, MD. Its faculty is mostly comprised of private practice obstetrics/gynecology groups. It supports a 3-year urogynecology fellowship. Johns Hopkins obstetrics/gynecology residents rotate through the hospital for general gynecology services and gynecologic oncology services. In addition, Johns Hopkins gynecologic oncology fellows rotate through the gynecologic oncology service. Institutional review board approval was obtained to abstract data from all patients who underwent a hysterectomy at the Greater Baltimore Medical Center between October 2004 and October 2006. We performed a retrospective chart analysis of all hysterectomy cases performed at our institution during this 2-year period. Using all of the 2005 hysterectomy Current Procedural Terminology codes, the medical records department generated a list of charts in order by medical record number. A list totaling 886 patients was generated. We abstracted the data sequentially by medical record number until we reached the number of charts needed for adequate power, as predetermined by statistical analysis. A total of 424 patients fit all of the inclusion criteria. We included all hysterectomies, with or without concurrent removal of adnexa (total abdominal, supracervical abdominal, vaginal, laparoscopic assisted vaginal, laparoscopic supracervical, and total laparoscopic hysterectomies), that were performed emergently or electively for benign disease. We excluded all gynecologic oncology cases, because all of theses cases had a resident and/or fellow assistant, and, as such, there were no nonteaching cases for comparison. Additionally, we presumed there would be greater blood loss and other adverse outcomes in this group of patients that could potentially bias our results. Patients were allocated to 1 of 2 groups: 1 in which there was a resident involved in the surgery and 1 in which there was not. All of the patients were initially seen, assessed, and consented by 673.e2
www.AJOG.org an attending surgeon. In 1 group (nonteaching group), the patient’s attending physician and his or her partner performed the operation. In the second group (teaching group), the attending operated on his or her patient with a resident or fellow assisting. The surgical outcomes that were measured included operating room (OR) time, a change in pre- and postsurgical hematocrit (HCT), estimated blood loss (EBL), and other perioperative complications. The data were abstracted using a predetermined Excel spreadsheet (Microsoft Corp, Redmond, WA) and entered directly in the computer database for later analysis. Three power analyses were performed, based on null hypotheses specifying clinical equivalence in mean OR time, change in mean pre- to postsurgical HCT levels, and mean EBL for teaching vs nonteaching cases to ensure that a sufficient number of charts were reviewed to achieve adequate statistical power. With respect to operative time, our null hypothesis was that the mean OR time was 20 minutes longer for teaching cases than for nonteaching cases (our definition of clinical equivalence). Given a power of 80% to reject this null hypothesis and an average OR time for nonteaching cases of 95 minutes, we assumed a 20% difference would be clin-
ically significant. With an alpha (1 tailed) set at 0.05, the required sample size for each group was 69. With respect to change in HCT, our null hypothesis was that the postoperative HCT would be 6 percentage points lower for teaching cases than for nonteaching cases (our definition of clinical equivalence). Again, we assigned a power of 80% to reject this null hypothesis. The mean postoperative HCT for nonteaching cases was 31.8% (estimated from our nonteaching sample of cases). Assuming that a 20% difference would be clinically significant and with alpha (1 tailed) set at 0.05, the required sample size for each of the 2 groups was 57. Finally, with respect to EBL, our null hypothesis was that the mean EBL for teaching cases is 150 mL higher (our definition of clinical equivalence) than the mean for nonteaching cases. Again, an 80% power to reject this null hypothesis was assigned. The mean EBL from our nonteaching cases was 280 mL. Assuming a 50% difference to be clinically significant, and with an alpha (1 tailed) set at 0.05, the required sample size for each of the 2 groups was 58 per group. Originally, we stratified the hysterectomy groups into abdominal, vaginal, and laparoscopic hysterectomies to determine whether there are more compli-
TABLE 1
Demographics Demographics
Nonteaching cases
Teaching cases
P value
Type of hysterectomy
.....................................................................................................................................................................................................................................
Abdominal, % (n)
61.0 (97/159)
62.3 (165/265)
.76
Vaginal, % (n)
17.6 (28/159)
24.2 (64/265)
.14
Laparoscopic, % (n)
21.4 (34/159)
13.6 (36/265)
.04
45.8 (⫾ 7.7)
47.5 (⫾ 10.4)
.07
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
Mean age, y (⫾ SD)
..............................................................................................................................................................................................................................................
Race
.....................................................................................................................................................................................................................................
Asian, % (n)
.6 (1/159)
.8 (2/262)
1.00
Black, % (n)
25.2 (40/159)
34.7 (91/262)
.05
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
Hispanic, % (n)
0.0 (0/159)
.8 (2/262)
.53
White, % (n)
74.2 (118/159)
62.2 (163/262)
.01
Other, % (n)
0.0 (0/159)
1.5 (4/262)
.30
Mean BMI (⫾ SD)
28.6 (⫾ 6.9)
29.3 (⫾ 6.1)
.29
Mean preoperative HCT (⫾ SD)
38.0 (⫾ 3.9)
37.5 (⫾ 4.4)
.32
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
American Journal of Obstetrics & Gynecology DECEMBER 2008
SGS Papers
www.AJOG.org
TABLE 2
Risk factors and comorbidities Comorbidity Diabetes, % (n)
Nonteaching cases
Teaching cases
P value
2.5 (4/158)
6.8 (18/264)
.070
Hypertension, % (n)
28.5 (45/158)
31.1 (82/264)
.59
Coronary artery disease, % (n)
11.4 (18/158)
14.4 (38/264)
.46
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Cerebrovascular accident, % (n)
0.0 (0/158)
1.5 (4/264)
.30
Anemia, % (n)
17.0 (27/159)
15.5 (41/265)
.68
Myomas, % (n)
51.6 (82/159)
38.9 (103/265)
.01
Menorrhagia, % (n)
57.2 (91/159)
51.3 (136/265)
.27
Adnexal mass, % (n)
11.3 (18/159)
14.8 (39/264)
.38
Tobacco use, % (n)
16.4 (24/146)
26.0 (67/258)
.04
1.3 (2/149)
1.2 (3/260)
1.00
19.6 (31/158)
13.2 (35/265)
.10
Postmenopausal bleeding, % (n)
3.8 (6/158)
3.4 (9/265)
.79
Neoplasia, % (n)
1.3 (2/159)
3.0 (8/265)
.33
Pelvic organ prolapse, % (n)
8.8 (14/159)
15.8 (42/265)
.04
Stress urinary incontinence, % (n)
6.9 (11/159)
7.5 (20/265)
.85
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Alcoholism, % (n)
and nonteaching cases (n ⫽ 159), thereby exceeding the number of cases in each group required to power the study to the requisite 80% level. Differences in teaching vs nonteaching cases were assessed using the Pearson 2 test for interval variables and Fisher’s exact test for nominal categories. Differences in means were examined using the independent samples t-test, with separate or pooled variance estimates, depending on the results of the Levine test for equality of variances of the 2 groups. Analyses were performed using SPSS 15.0 software (SPSS, Inc, Chicago, IL).
..............................................................................................................................................................................................................................................
Dysmenorrhea, % (n)
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Chronic pelvic pain, % (n)
12.7 (20/157)
7.5 (20/265)
.09
Psychological indications, % (n)
1.3 (2/159)
3.0 (8/265)
.33
Mean number of other comorbidities (⫾ SD)
1.3 (⫾ 1.1)
1.3 (⫾ 1.3)
.77
.............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
..............................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
cations with the newer minimally invasive techniques, compared with traditional hysterectomies. After data analysis we found no significant difference
between laparoscopic, vaginal, and open hysterectomies. We therefore combined all types of hysterectomy and separated the total number into teaching (n ⫽ 265)
R ESULTS A total of 424 patients were included in this study. The demographics and comorbidities are summarized in Table 1. There was an overall significant difference in race between the 2 groups, with more nonwhites in the teaching vs the nonteaching groups. Teaching cases tended to have more African Americans in them, which approached statistical significance (25.2% vs 34.7%; P ⫽ .051). Whites accounted for a statistically significantly larger portion of cases in the nonteaching group (74.2% vs 62.2%; P ⫽ .014). The nonteaching group also had a statistically significantly larger proportion
TABLE 3
Surgical outcomes Outcome
Teaching cases
P value
94.8 (⫾ 47.0)
107.4 (⫾ 42.4)
.005
1.5 (⫾ 1.2)
1.3 (⫾ 1.1)
.12
Supracervical hysterectomy, % (n)
17.6 (23/131)
17.5 (35/200)
1.00
Total hysterectomy, % (n)
82.4 (108/131)
81.5 (163/200)
.89
272.0 (⫾ 280.0)
242.7 (⫾ 204.1)
.22
31.78 (⫾ 4.2)
32.1 (⫾ 4.1)
.49
Mean OR time, min (⫾ SD)
Nonteaching cases
................................................................................................................................................................................................................................................................................................................................................................................
Mean number of concurrent surgeries (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................
Mean EBL, mL (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................
Mean postoperative HCT (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................
Mean attending surgeon experience, y (⫾ SD)
25.1 (⫾ 5.1)
21.3 (⫾ 8.6)
.00
Adenomyosis, % (n)
42.1 (67/159)
38.9 (103/265)
.54
Endometriosis, % (n)
12.6 (20/159)
11.0 (29/264)
.64
Leiomyoma, % (n)
69.8 (111/159)
70.9 (188/265)
.83
264.3 (⫾ 301.1)
288.1 (⫾ 375.7)
.5
................................................................................................................................................................................................................................................................................................................................................................................ a ................................................................................................................................................................................................................................................................................................................................................................................ a ................................................................................................................................................................................................................................................................................................................................................................................ a ................................................................................................................................................................................................................................................................................................................................................................................
Mean uterine weight, g (⫾ SD)
................................................................................................................................................................................................................................................................................................................................................................................ a
By pathology.
................................................................................................................................................................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
DECEMBER 2008 American Journal of Obstetrics & Gynecology
673.e3
SGS Papers
www.AJOG.org
TABLE 4
Adverse outcomes and complications Complication Transfusion, % (n)
Nonteaching cases
Teaching cases
P value
4.4 (7/158)
4.2 (11/261)
1.00
22.0 (35/159)
16.7 (44/263)
.2
Wound infection, % (n)
3.1 (5/159)
1.9 (5/263)
.51
Wound sepsis/dehiscence, % (n)
1.9 (3/159)
0.4 (1/263)
.15
Seroma, % (n)
2.5 (4/159)
0.0 (0/263)
.02
Abcess, % (n)
1.9 (3/158)
1.1 (3/263)
.68
Ileus, % (n)
3.8 (6/159)
1.9 (5/263)
.34
Readmission to hospital, % (n)
8.8 (14/159)
7.2 (19/263)
.58
Return to OR, % (n)
2.5 (4/159)
2.7 (7/263)
1.00
Atelectasis, % (n)
4.4 (7/159)
7.2 (19/263)
.3
Pneumonia, % (n)
1.3 (2/159)
0.4 (1/263)
.56
Cystitis, % (n)
2.5 (4/159)
2.7 (7/263)
1.00
Injury to viscous, % (n)
1.3 (2/159)
1.9 (5/263)
.72
Ureteral injury, % (n)
0.0 (0/159)
0.4 (1/265)
1.00
Cystotomy, % (n)
1.9 (3/159)
1.5 (4/265)
1.00
SBO, % (n)
2.1 (2/97)
3.0 (5/165)
1.00
Hematoma, % (n)
1.6 (2/125)
1.3 (3/229)
1.00
Fistula, % (n)
0.0 (0/28)
1.6 (1/64)
1.00
Nerve injury, % (n)
0.0 (0/28)
1.6 (1/64)
1.00
Thromboembolism, % (n)
1.0 (1/97)
1.2 (2/165)
1.00
Urinary retention, % (n)
3.1 (5/159)
3.4 (9/265)
1.00
30.2 (48/159)
30.2 (79/262)
1.00
5.0 (8/159)
0.8 (2/265)
.01
..............................................................................................................................................................................................................................................
Fever, % (n)
.............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. .............................................................................................................................................................................................................................................. ..............................................................................................................................................................................................................................................
Adhesions, % (n)
.............................................................................................................................................................................................................................................. a
Other, % (n)
.............................................................................................................................................................................................................................................. a
Other complications: hip sprain, lost laparotomy sponge, readmission for gastroenteritis, a chest wall abscess at the site of concurrent skin tag removal, syncope, and peritonitis.
..............................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
of laparoscopic hysterectomies (21.4% vs 13.6%; P ⫽ .042). The mean body mass index (kilograms per square meter), mean age, and preoperative hematocrit were similar between the 2 groups. The risk factors and comorbidities for the 2 groups are summarized in Table 2. The nonteaching groups were more likely to have a preoperative diagnosis for leiomyomata uteri (51.6% vs 38.9%; P ⫽ .012) and less likely to be smokers (16.4% vs 26.0%; P ⫽ .035). However, when the data were analyzed for uterine size and pathological confirmation of leiomyomas, there was no difference between the 2 groups (Table 3). Table 3 summarizes the surgical outcomes for our study. There was no statis673.e4
tically significant difference between the 2 groups for 2 major outcomes measured, such as mean EBL (milliliters) (272.0 ⫾ 280 vs 242.2 ⫾ 204.1; P ⫽ .220) and postoperative HTC (percent) (31.78 ⫾ 4.2 vs 32.1 ⫾ 4.1; P ⫽ .49). The OR time difference in minutes was 94.8 ⫾ 47.0 vs 107.4 ⫾ 42.4; P ⫽ .005 in the nonteaching vs teaching groups, respectively. The mean number of concurrent surgeries (1.5 ⫾ 1.2 vs 1.3 ⫾ 1.1; P ⫽ .12) and percent of supracervical hysterectomies (17.6% vs 17.5%; P ⫽ 1.00) were similar in nonteaching and teaching groups, respectively. Teaching cases were more likely performed by attendings with less years of experience (21.3 ⫾ 8.6 vs 25.1 ⫾ 5.1; P ⫽ .00).
American Journal of Obstetrics & Gynecology DECEMBER 2008
We also examined the data for the adverse outcomes that are listed in Table 4. There was a statistically significantly higher incidence of seromas (2.5% vs 0.0%; P ⫽ .02) and “other miscellaneous adverse outcomes” (5.0% vs 0.8%; P ⫽ .007) seen between the 2 types of cases. Other miscellaneous adverse outcomes were a hip sprain, lost laparotomy sponge, readmission for gastroenteritis, a chest wall abscess at the site of concurrent skin tag removal, syncope, and peritonitis. There was no significant difference in all other complications studied in both groups. Bivariate analysis was used to look for trends based on years of surgical experience (Table 5). There was no correlation between the residents’ levels of postgraduate training (postgraduate year level) and EBL, OR time, or postoperative HCT. For nonteaching cases, there was a moderate inverse linear relationship between the attending surgeons’ years of experience and OR time (r ⫽ -0.314; P ⬍ .001). For teaching cases, there was a moderate inverse linear relationship between the fellow surgeon’s years of experience and EBL (r ⫽ -0 .278; P ⫽ .023). Similar correlations were observed when all 424 cases were analyzed (Table 6). Additionally, there is a slight inverse linear relationship between the attending surgeons’ years of experience and postoperative HCT level (r ⫽ -0.102; P ⫽ .038).
C OMMENT To our knowledge, this is the first study that compares outcomes for hysterectomies involving obstetrics/gynecology residents, compared with those performed solely by attending physicians. Others have examined outcomes of teaching other types of gynecological surgery. Similarly, these authors have found no significant differences in adverse outcomes between teaching and nonteaching cases.2,3,5-7 The results of our study indicate some interesting trends. Teaching hysterectomies warrant more time. The need for added time to complete a hysterectomy goes beyond the 4 years of an obstetrics-gynecology
SGS Papers
www.AJOG.org
TABLE 5
Analysis of surgical experience and outcomes in nonteaching and teaching groups OR time
EBL
Postoperative HCT
Nonteaching group
.......................................................................................................................................................................................................................................................................................................................................................................
Attending surgeons’ years of experience
Pearson correlation
-0.314
-0.072
-0.099
0.000
0.376
0.220
.....................................................................................................................................................................................................................................
Significance (2 tailed)
................................................................................................................................................................................................................................................................................................................................................................................
Teaching group
.......................................................................................................................................................................................................................................................................................................................................................................
Attending surgeons’ years of experience
Pearson correlation
-0.10
0.04
-0.10
Significance (2 tailed)
0.11
0.49
0.11
Pearson correlation
0.002
0.02
0.07
Significance (2 tailed)
0.98
0.82
0.31
Pearson correlation
0.12
-0.28
0.22
Significance (2 tailed)
0.33
0.02
0.08
.....................................................................................................................................................................................................................................
.......................................................................................................................................................................................................................................................................................................................................................................
Resident surgeons’ years of experience
.....................................................................................................................................................................................................................................
.......................................................................................................................................................................................................................................................................................................................................................................
Fellow surgeons’ years of experience
.....................................................................................................................................................................................................................................
................................................................................................................................................................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
residency well into the years of practice as an obstetrics/gynecology attending. However, this added time needed to perform surgery might be well balanced by less blood loss and other adverse events such as seroma formation. Surprisingly, no trend or association was seen between the residents’ levels of postgraduate training (postgraduate year level) and the 3 major outcome variables measured in this study. However, we did find that as the urogynecology fellows’ years of experience increased, EBL tended to decrease. We speculated this trend might have been unmasked because the fellows were probably given more independence while operating than the residents, regardless of their number of years of training. When we examined associations between years of experience for the attendings, some interesting results were found. The surgical groups with less ex-
perienced attendings (based on the number of years following residency training) took longer to operate than more experienced attendings. However, less experienced attendings tended to have patients with higher postoperative hematocrits. This trend implies that less experienced attendings are more likely to operate more slowly and more cautiously than more experienced attendings. This may be because the less experienced attendings were more likely to be involved in a teaching hysterectomy, which inherently warrants more caution and time. It is unclear from reviewing the patients’ charts which criteria were used by the surgical attending to decide whether a resident or his or her partner were to assist in a given case. We also noticed a trend away from teaching as obstetricsgynecology attendings gained years of experience and when newer techniques
were used. This was surprising, but there might be several plausible explanations. First, older attendings may have been more likely to have been involved in litigation in the past and thus may shy away from the perceived risk of teaching. Second, they may be under greater financial pressure to perform a case quickly to return to a busy office practice. Third, being farther from their residency training may lead to a sense of insecurity regarding their skill level with newer ways of performing hysterectomies. We have a 3-year fellowship in urogynecology at Greater Baltimore Medical Center. The faculty members in this program are actively involved with resident/ fellowship education. Therefore, we expected to have a higher percentage of patients with pelvic organ prolapse in the teaching group. The nonteaching group was more likely to have a preoperative diagnosis for fibroids. We are not sure
TABLE 6
Analysis of surgical experience and outcomes in all cases Surgical experience Attending surgeons’ years of experience
OR time Pearson correlation
EBL
Postoperative HCT
-0.18
0.02
-0.10
0.00
0.70
0.04
...........................................................................................................................................................................................................................................
Significance (2 tailed)
................................................................................................................................................................................................................................................................................................................................................................................
Resident surgeons’ years of experience
Pearson correlation
0.002
0.02
0.07
Significance (2 tailed)
0.98
0.82
0.31
Pearson correlation
0.12
-0.28
0.22
Significance (2 tailed)
0.33
0.02
0.08
...........................................................................................................................................................................................................................................
................................................................................................................................................................................................................................................................................................................................................................................
Fellow surgeons’ years of experience
...........................................................................................................................................................................................................................................
................................................................................................................................................................................................................................................................................................................................................................................
Akingba. Hysterectomies performed by supervised residents vs those by attendings alone. Am J Obstet Gynecol 2008.
DECEMBER 2008 American Journal of Obstetrics & Gynecology
673.e5
SGS Papers why this is, although one could speculate that these attendings may have excluded residents from cases they felt would be more technically challenging. There were significantly more seromas and other miscellaneous adverse outcomes in the nonteaching hysterectomy cases. It is entirely possible that there were some seromas seen in the office that were not readmitted, falsely skewing the statistical significance for this result. Because of time and budget constraints, we were limited to reviewing hospital charts for all of the patients in this study. This would limit our ability to detect seromas and wound infections that were handled on an outpatient basis by the various private practices that operate at Greater Baltimore Medical Center. We also saw a significant difference in “other miscellaneous complications.” These included hip sprain, lost laparotomy sponge, readmission for gastroenteritis, a chest wall abscess at the site of concurrent skin tag removal, syncope, and peritonitis. We were not adequately powered to detect a difference in any of these variables. To detect a 20% difference in these rare outcomes, our initial power analyses determined that we would need 21,000 people in each group. We collected data on these variables to look for trends that could be used in a future metaanalysis. Teaching cases tended to have more African Americans, a demographic finding that approached statistical significance, and more nonwhites, which did
673.e6
www.AJOG.org reach statistical significance. With no direct measure for socioeconomic status between the 2 groups in our review, perhaps this may point to a greater trend among more affluent patients to exclude residents from their surgeries. We have no explanation why nonteaching cases tended to have more nonsmokers. Limitations of our study obviously include its retrospective design and access to only hospital charts. The degree of residents’ and fellows’ participation in teaching cases is hard to determine from the hospital records. Was the resident/ fellow a surgeon who performed more than 50% of the case or just an assistant who mostly observed it? Based on our knowledge about general practices by different attendings in our institution, we assumed that all the residents/fellows were active participants in performing hysterectomy and therefore could affect the hysterectomy outcomes. Despite these limitations, our data strongly support the conclusion that teaching hysterectomies are as safe as nonteaching hysterectomies when performed under the guidance of competent attending surgeons. Given the time and expense of a prospective study, coupled with the apparent bias on the part of the public, recruiting patients for such a study might prove difficult, if not improbable. Some unanswered questions include what basis the attendings in our study used to decide whether to perform the surgeries alone or with a resident, why
American Journal of Obstetrics & Gynecology DECEMBER 2008
older attendings tended to exclude residents from their cases, why patients who smoked tended to undergo teaching hysterectomies, and whether race is a factor for excluding or allowing residents to be included in a hysterectomy. We propose that a national database could be used to look at health disparities and attitudes about teaching surgery cases to see whether lower socioeconomic status, race, and overall health of a patient are deciding factors for allowing f student surgeons to operate. REFERENCES 1. Keshavarz H, Hillis SD, Kieke BA, et al. Hysterectomy surveillance—United States, 19941999. WWMR CDC Surveill Summ 2002;51: 1-8. 2. Abouassaly R, Steinberg JR, Lemieux M, et al. Complications of tension-free vaginal tape surgery: a multi-institutional review. BJU Int 2004;94:110-3. 3. McLennan MT, Melick CF. Bladder perforation during tension-free vaginal tape procedures: Analysis of learning curve and risk factors. Obstet Gynecol 2005;106:1000-4. 4. Kim HN, Gates E, Lo B. What hysterectomy patients want to know about the roles of residents and medical students in their care. Acad Med 1998;73:339-41. 5. Shaked A, Calderom I, Durst A. Safety of surgical procedures performed by residents. Arch Surg 1991;126:559-60. 6. Coates KW, Kuehl TJ, Bachofen CG, Shull BL. Analysis of surgical complications and patient outcomes in a residency training program. Am J Obstet Gynecol 2001;184:1380-3. 7. Sorosky JI, Anderson B. Surgical experiences and training of residents: perspective of experienced gynecologic oncologists. Gynecol Oncol 1999;75:222-3.