- Email: [email protected]
The impact of central line simulation before the ICU experience
The American Journal of Surgery (2009) 197, 533–536
Association for Surgical Education
The impact of central line simulation before the ICU experience Rebecca C. Britt, M.D.a,*, T.J. Novosel, M.D.a, L.D. Britt, M.D., M.P.H.a, Maura Sullivan, Ph.D., M.S.N.b a
Department of Surgery, Eastern Virginia Medical School, Norfolk, VA; bDepartment of Surgery, University of Southern California, Los Angeles, CA, USA KEYWORDS: Central line training; Patient safety; Proficiency training; Resident simulation
Abstract BACKGROUND: This study was designed to evaluate whether resident performance of placing central lines improved after simulation training on newly available partial-task simulators. METHODS: This study was designed as a prospective, randomized controlled trial of standard training versus simulated training using CentralLine Man (SimuLab, Seattle, WA, USA). After receiving a lecture on central line placement, all junior residents on the trauma rotation were randomized on a monthly alternating schedule. Equivalency of groups was determined with a self-reported survey. All lines placed by the participants were monitored, and data were collected on performance and complications. RESULTS: The 2 groups (n ⫽ 34; 21 standard and 13 simulated) were equivalent at baseline. The simulated training group had a significantly higher level of comfort and ability than the standard training group. The simulated group outperformed the standard group on 12 of the 15 specific variables monitored, although this did not reach statistical significance. There were significantly more complications in the standard group. CONCLUSIONS: Simulation for central line placement using a partial-task simulator does positively impact resident performance. © 2009 Elsevier Inc. All rights reserved.
The classic dogma of “see one, do one, teach one” for resident education is no longer accepted in the current health care environment. The apprenticeship model, in which bedside procedures are performed by junior residents under the supervision of senior residents and faculty, leads to a wide variation in the skill sets that are taught. Residents express discomfort with this model, particularly with regard to performing invasive procedures.1 * Corresponding author. Tel.: ⫹01-757-446-8950; fax: ⫹01-757-4468951. E-mail address: [email protected] Manuscript received May 2, 2008; revised manuscript November 4, 2008
0002-9610/$ - see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.amjsurg.2008.11.016
Surgical skills are increasingly taught using simulation training before task performance on the patient, creating a “pretrained novice”2 who is skilled and comfortable with task performance. Simulators have been shown to improve task performance in the operating room3 as well as in developing endovascular skills.4 Improved independence and proficiency was demonstrated by internal medicine residents trained to place central lines under the direction of a cardiologist in the catheterization laboratory.5 Velmahos et al demonstrated that a surgical skills laboratory using an inanimate model improved the technical skills of surgical residents in placing central lines.6 The results of some studies have shown that education of physicians and nursing staff can decrease the risk of blood-
534
The American Journal of Surgery, Vol 197, No 4, April 2009
Table 1 Comparative self-assessed survey of subjects at study enrollmenta Skills surveyed
Standard (n ⫽ 21)
Simulated (n ⫽ 13)
P
No. of previous lines Previous IJ Previous subclavian vein Knowledge of preparation1–5 Knowledge of equipment1–5 Knowledge of technique1–5 Perception of ability1–5
7.9 1.9 4.9 3.95 3.62 3.33 2.86
10.6 2.3 4.6 3.85 3.77 3.46 2.85
.44 .66 .91 .75 .65 .67 .98
a
(10.7) (2.6) (8.5) (.92) (1.02) (.91) (1.12)
(8.2) (2.6) (4.8) (.80) (.73) (.78) (1.21)
Numbers are expressed as mean ⫾ SD.
stream infection. A standardized education session (standard training) was given to junior residents regarding proper sterile procedure, leading to a 28% decrease in bloodstream infection rates in the intensive care unit (ICU).7 A multiapproach intervention to decrease catheter-related infections using educational slides and practical demonstrations for medical residents, nurses, and nursing assistants also led to a marked decrease in nosocomial infections.8 Proper choice of placement site has also been identified as a factor in nosocomial infections, with subclavian placement being the preferred site rather than both internal jugular and femoral central lines.9,10 Recent innovations have led to the introduction of a partial-task simulator designed to teach central line placement on a mannequin before performing the task is performed on patients. Although several studies have examined the impact of supervised training on resident performance for central line placement, no study has been done to show the effectiveness of a partial-task simulator for this task. This study was designed to evaluate whether resident performance in placing central lines improved after simulation training. In addition, we assessed whether patient outcomes, such as infection and pneumothorax, were impacted by resident simulation training.
Methods After obtaining Institutional Review Board approval, all postgraduate junior surgery residents (n ⫽ 34) who rotated through the Trauma Service at Sentara Norfolk General Hospital were asked to participate in this controlled randomized trial. Each participant was assigned to either the control group or the experimental group, with randomization done monthly for all junior residents who consented to participate. Before instruction, all residents completed a self-reported survey of previous experience to determine equivalency of groups. The control group received a standard lecture followed by the traditional apprenticeship model of instruction and practice on real patients with either the postgraduate year 4 trauma resident or trauma fellow supervising the procedure.
The experimental group (simulated training) received the same standard lecture followed by a hands-on demonstration and performance of both subclavian and internal jugular line placement by a single surgical critical care attending using the CentralLineMan (Simulab) partial-task simulator. The trainee was judged to be proficient on the simulator by the attending surgeon before performing on any real patients. Every line placed by each subject was evaluated by either the trauma fellow or 1 attending critical care surgeon using an objective structured checklist. Data regarding performance and complications was collected. Performance parameters include hand washing, preparation and positioning, landmark identification, and needle insertion techniques. Complications monitored included arterial puncture, pneumothorax, line positioning, and the inability of the junior resident to place the line. Line days and line infections were also monitored for each month of the study. Statistical analysis was done using MedCalc for Windows, version 9.3.3.0 (MedCalc Software, Mariakerke, Belgium). Significance was assessed using comparison of means and chisquare comparison of proportions; P ⬍ .05 was defined as significant.
Results A total of 34 residents participated in the study: 21 in the standard group and 13 in the simulated group. The residents had equal experience and knowledge at the initiation of training (Table 1). Thirty-nine central line attempts were monitored in the standard group, and 34 were monitored in the simulated group. Five of the attempts were internal jugular, all using ultrasound (US), and the remaining 68 lines were subclavian. The simulated group had a significantly higher level of comfort and ability as judged by the evaluator (Table 2). There was no significant difference in the number of sticks to achieve line placement between the 2 groups. The simulated group outperformed the standard group on 7 of the 10 performance variables measured, although these did not reach statistical significance (Table 3). There were significantly more complications in the standard group, including pneumothorax, arterial puncture, and inability to complete the procedure, than in the simulated group (Table 4). The senior resident or fellow was able to successfully place all
Table 2 Resident comfort and ability as judged by evaluatora Performance rating 1–5
Resident comfort Resident ability1–5
Standard (n ⫽ 39)
Simulated (n ⫽ 34)
P
2.92 (.87) 2.89 (.85)
3.35 (.84) 3.38 (1.04)
.03 .03
Numbers are expressed as mean ⫾ SD.
a
R.C. Britt et al. Table 3
Central line simulation
535 Table 5
Performance measures
Performance measures Improper hand washing Improper preparation Improper drape Inappropriate setup No Trendelenburg positioning Incorrect landmark ID Incorrect angle Unable to cannulate on first attempt Average sticks to cannulation Unable to pass line over wire
Standard (%) n ⫽ 39 3/39 2/39 7/39 4/39
(7.7) (5.1) (17.9) (10.3)
5/39 (12.8) 1/39 (2.6) 9/39 (23) 27/39 (69.2)
Simulated (%) n ⫽ 34 3/34 1/34 2/34 3/34
(8.8) (2.9) (5.8) (8.8)
6/34 (17.6) 0/34 (0) 5/34 (15) 17/34 (50)
P .80 .91 .22 .86 .81 .96 .55 .15
2.59 (1.41)
2.41 (1.86)
.64
12/39 (30.8)
8/43 (23.5)
.66
but 1 of the lines that the study subjects were not able to do. One line was attempted unsuccessfully by the attending after failed attempts by all the trainees. The overall performance of the simulated group was superior to the standard group in both performance and avoidance of complications (Table 5). During the simulated months, there were 8 line infections and 495 line days. Four of the bloodstream infections occurred in patients with lines not placed as part of the study (1 tunneled dialysis catheter and 3 lines placed outside of the ICU). The remaining 4 infections were in lines place by the simulated group, with 480 line days and .008 infections/ line day. The standard group had 3 line infections in 595 line days and .005 infections/line day (P ⫽ .8).
Comments Simulation for central line placement using the CentralLineMan partial-task simulator did positively affect resident performance on patients. This was particularly significant with regard to line complications. Complications from
Table 4
Complications
Complications Arterial puncture Need for senior resident to take over Inability to place line Pneumothorax Blood stream infection Improper line position on x-ray
Standard (%) n ⫽ 39 1/39 (2.6)
Simulated (%) n ⫽ 34 0/34 (0)
P .96
22/39 (56) 11/39 (28.2) 4/39 (10)
12/34 (35) 5/34 (14.7) 0/34 (0)
.11 .25 .17
3/39 (7.7)
4/34 (11.8)
.84
2/39 (5.1)
3/34 (8.8)
.87
Summary of performance
Performance element
Standard (%)
Simulated (%)
P
Performance errors Complications
70/351 (19.9) 43/195 (22.1)
45/306 (14.7) 24/170 (14.1)
.09 .07
central lines contribute significantly to increased health care costs. Although catheter-related infection contributes significantly to hospital charges, averaging in 1 study 43% of the total hospital cost,11 simulation does not appear to significantly alter infection risk. Pneumothorax is a significant morbidity related to central line placement and a potential source of mortality if not recognized. We believe that the simulator allows for teaching appropriate angle of approach with the needle and results in decreased risk of pneumothorax. In addition, although these did not reach statistical significance, we were encouraged by the decrease in arterial puncture, the need for senior resident intervention, and inability to place the line in the simulated group. The traditional model in our hospital was for residents to be considered “signed off” on central lines after being monitored for 5 consecutive internal jugular and subclavian lines. We considered the need for a senior resident to take over the line as a complication because we were attempting to clarify junior resident ability to safely place a line. When analyzing the complication data without including the need for senior resident to take over the procedure, we still saw a trend toward improvement in the simulated group. From our observations, we have implemented a mandatory central line simulation curriculum for our junior residents they performance procedures on any patients. In addition, we implemented mandatory observation by an attending surgeon of line performance before residents were allowed to do any central lines unsupervised. The most significant findings in the study relate to increased resident comfort and ability in the simulated group. One of the main goals of residency training programs is to train residents to be both confident and competent when performing procedural skills. Learners with increased self-efficacy (belief in their ability to accomplish a particular task) demonstrate higher achievement.12 The fact that residents in the simulated group also demonstrated improvement over those in the standard group on 7 of 10 performance measures is encouraging as we continue to move toward proficiency training for surgical skills in residency programs. Despite the prospective, randomized design, this study is associated with some limitations that may have impacted the outcomes. First, we were unable to record any patient data, such as reason for hospitalization, body mass index, and other patient-specific factors, clearly impacting central line placement performance because of limitations imposed by our IRB. We attempted to control for this by our randomization procedure and by monitoring as many line performances as possible by each resident, but this remains a limit to the study. Second, the evaluators were not blinded
536 to the groups, which certainly could introduce bias. We attempted to control for variability among the evaluators by only allowing 2 surgeons to evaluate the performance and by using an objective structured checklist. Last, because we randomized groups on a month-to-month basis and because there were a different number of residents rotating per month, we did not have the same number of subjects in the 2 groups. Concerns with simulation include whether the learner “buys into” the model and how well the models are able to simulate the procedural steps. The current models allow for teaching both subclavian and internal jugular line placement and include the use of US. Our institution previously reported that central line simulation was believed by residents to be beneficial and rated the current model in use an average of 4.5 out of 5 points for realism.13 Certainly, as the models continue to evolve they will become more realistic. We chose not to incorporate US training into this study, but we are assessing the addition of this modality to our standard training. No proficiency standard currently exists for training on the central line partial-task simulator. Work is currently underway to establish proficiency standards for training, which will likely lead to even more significant improvement in performance for the simulated trainee.
References 1. Huang GC, Smith CC, Gordon GE, et al. Beyond the comfort zone: residents assess their comfort performing inpatient medical procedures. Am J Med 2006;119:e17– e24.
The American Journal of Surgery, Vol 197, No 4, April 2009 2. Van Sickle KR, Ritter EM, Smith CD. The pretrained novice: using simulation-based training to improve learning in the operating room. Surg Innov 2006;13:198 –204. 3. Seymour NE, Gallagher AG, Roman SA, et al. Virtual reality training improves operating room performance: results of a randomized, double-blinded study. Ann Surg 2002;236:458 – 64. 4. Hsu JH, Younan D, Pandalai S, et al. Use of computer simulation for determining endovascular skill levels in a carotid stenting model. J Vasc Surg 2004;40:1118 –25. 5. Ramakrishna G, Higano ST, McDonald FS, et al. A curricular initiative for internal medicine residents to enhance proficiency in internal jugular central venous line placement. Mayo Clin Proc 2005;80: 212– 8. 6. Velmahos GC, Toutouzas KG, Sillin LF, et al. Cognitive task analysis for teaching technical skills in an inanimate surgical skill laboratory. Am J Surg 2004;187:114 –9. 7. Sherertz RJ, Ely EW, Westbrook DM, et al. Education of physiciansin-training can decrease the risk for vascular catheter infection. Ann Intern Med 2000;132:641– 8. 8. Eggimann P, Harbath S, Constantin MN, et al. Impact of a prevention strategy targeted at vascular-access care on incidence of infections acquired in intensive care. Lancet 2000;355:1864 – 8. 9. Charlambous C, Swoboda SM, Dick J, et al. Risk factors and clinical impact of central line infections in the surgical intensive care unit. Arch Surg 1998;133:1241– 6. 10. Merrer J, De Jonghe B, Golliot F, et al. Complications of femoral and subclavian venous catheterization in critically ill patients: A randomized controlled trial. JAMA 2001;286:700 –7. 11. Shannon RP, Patel B, Shannon AH, et al. Economics of central-line associated bloodstream infections. Am J Med Qual 2006;21(Suppl): 7S–16S. 12. Bandura A. Self-efficacy: the exercise of control. New York, NY: W. H. Freeman; 1997. 13. Britt RC, Reed SF, Britt LD. Central line simulation: A new training algorithm. Am Surg 2007;73:680 –2.
Association for Surgical Education
The impact of central line simulation before the ICU experience Rebecca C. Britt, M.D.a,*, T.J. Novosel, M.D.a, L.D. Britt, M.D., M.P.H.a, Maura Sullivan, Ph.D., M.S.N.b a
Department of Surgery, Eastern Virginia Medical School, Norfolk, VA; bDepartment of Surgery, University of Southern California, Los Angeles, CA, USA KEYWORDS: Central line training; Patient safety; Proficiency training; Resident simulation
Abstract BACKGROUND: This study was designed to evaluate whether resident performance of placing central lines improved after simulation training on newly available partial-task simulators. METHODS: This study was designed as a prospective, randomized controlled trial of standard training versus simulated training using CentralLine Man (SimuLab, Seattle, WA, USA). After receiving a lecture on central line placement, all junior residents on the trauma rotation were randomized on a monthly alternating schedule. Equivalency of groups was determined with a self-reported survey. All lines placed by the participants were monitored, and data were collected on performance and complications. RESULTS: The 2 groups (n ⫽ 34; 21 standard and 13 simulated) were equivalent at baseline. The simulated training group had a significantly higher level of comfort and ability than the standard training group. The simulated group outperformed the standard group on 12 of the 15 specific variables monitored, although this did not reach statistical significance. There were significantly more complications in the standard group. CONCLUSIONS: Simulation for central line placement using a partial-task simulator does positively impact resident performance. © 2009 Elsevier Inc. All rights reserved.
The classic dogma of “see one, do one, teach one” for resident education is no longer accepted in the current health care environment. The apprenticeship model, in which bedside procedures are performed by junior residents under the supervision of senior residents and faculty, leads to a wide variation in the skill sets that are taught. Residents express discomfort with this model, particularly with regard to performing invasive procedures.1 * Corresponding author. Tel.: ⫹01-757-446-8950; fax: ⫹01-757-4468951. E-mail address: [email protected] Manuscript received May 2, 2008; revised manuscript November 4, 2008
0002-9610/$ - see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.amjsurg.2008.11.016
Surgical skills are increasingly taught using simulation training before task performance on the patient, creating a “pretrained novice”2 who is skilled and comfortable with task performance. Simulators have been shown to improve task performance in the operating room3 as well as in developing endovascular skills.4 Improved independence and proficiency was demonstrated by internal medicine residents trained to place central lines under the direction of a cardiologist in the catheterization laboratory.5 Velmahos et al demonstrated that a surgical skills laboratory using an inanimate model improved the technical skills of surgical residents in placing central lines.6 The results of some studies have shown that education of physicians and nursing staff can decrease the risk of blood-
534
The American Journal of Surgery, Vol 197, No 4, April 2009
Table 1 Comparative self-assessed survey of subjects at study enrollmenta Skills surveyed
Standard (n ⫽ 21)
Simulated (n ⫽ 13)
P
No. of previous lines Previous IJ Previous subclavian vein Knowledge of preparation1–5 Knowledge of equipment1–5 Knowledge of technique1–5 Perception of ability1–5
7.9 1.9 4.9 3.95 3.62 3.33 2.86
10.6 2.3 4.6 3.85 3.77 3.46 2.85
.44 .66 .91 .75 .65 .67 .98
a
(10.7) (2.6) (8.5) (.92) (1.02) (.91) (1.12)
(8.2) (2.6) (4.8) (.80) (.73) (.78) (1.21)
Numbers are expressed as mean ⫾ SD.
stream infection. A standardized education session (standard training) was given to junior residents regarding proper sterile procedure, leading to a 28% decrease in bloodstream infection rates in the intensive care unit (ICU).7 A multiapproach intervention to decrease catheter-related infections using educational slides and practical demonstrations for medical residents, nurses, and nursing assistants also led to a marked decrease in nosocomial infections.8 Proper choice of placement site has also been identified as a factor in nosocomial infections, with subclavian placement being the preferred site rather than both internal jugular and femoral central lines.9,10 Recent innovations have led to the introduction of a partial-task simulator designed to teach central line placement on a mannequin before performing the task is performed on patients. Although several studies have examined the impact of supervised training on resident performance for central line placement, no study has been done to show the effectiveness of a partial-task simulator for this task. This study was designed to evaluate whether resident performance in placing central lines improved after simulation training. In addition, we assessed whether patient outcomes, such as infection and pneumothorax, were impacted by resident simulation training.
Methods After obtaining Institutional Review Board approval, all postgraduate junior surgery residents (n ⫽ 34) who rotated through the Trauma Service at Sentara Norfolk General Hospital were asked to participate in this controlled randomized trial. Each participant was assigned to either the control group or the experimental group, with randomization done monthly for all junior residents who consented to participate. Before instruction, all residents completed a self-reported survey of previous experience to determine equivalency of groups. The control group received a standard lecture followed by the traditional apprenticeship model of instruction and practice on real patients with either the postgraduate year 4 trauma resident or trauma fellow supervising the procedure.
The experimental group (simulated training) received the same standard lecture followed by a hands-on demonstration and performance of both subclavian and internal jugular line placement by a single surgical critical care attending using the CentralLineMan (Simulab) partial-task simulator. The trainee was judged to be proficient on the simulator by the attending surgeon before performing on any real patients. Every line placed by each subject was evaluated by either the trauma fellow or 1 attending critical care surgeon using an objective structured checklist. Data regarding performance and complications was collected. Performance parameters include hand washing, preparation and positioning, landmark identification, and needle insertion techniques. Complications monitored included arterial puncture, pneumothorax, line positioning, and the inability of the junior resident to place the line. Line days and line infections were also monitored for each month of the study. Statistical analysis was done using MedCalc for Windows, version 9.3.3.0 (MedCalc Software, Mariakerke, Belgium). Significance was assessed using comparison of means and chisquare comparison of proportions; P ⬍ .05 was defined as significant.
Results A total of 34 residents participated in the study: 21 in the standard group and 13 in the simulated group. The residents had equal experience and knowledge at the initiation of training (Table 1). Thirty-nine central line attempts were monitored in the standard group, and 34 were monitored in the simulated group. Five of the attempts were internal jugular, all using ultrasound (US), and the remaining 68 lines were subclavian. The simulated group had a significantly higher level of comfort and ability as judged by the evaluator (Table 2). There was no significant difference in the number of sticks to achieve line placement between the 2 groups. The simulated group outperformed the standard group on 7 of the 10 performance variables measured, although these did not reach statistical significance (Table 3). There were significantly more complications in the standard group, including pneumothorax, arterial puncture, and inability to complete the procedure, than in the simulated group (Table 4). The senior resident or fellow was able to successfully place all
Table 2 Resident comfort and ability as judged by evaluatora Performance rating 1–5
Resident comfort Resident ability1–5
Standard (n ⫽ 39)
Simulated (n ⫽ 34)
P
2.92 (.87) 2.89 (.85)
3.35 (.84) 3.38 (1.04)
.03 .03
Numbers are expressed as mean ⫾ SD.
a
R.C. Britt et al. Table 3
Central line simulation
535 Table 5
Performance measures
Performance measures Improper hand washing Improper preparation Improper drape Inappropriate setup No Trendelenburg positioning Incorrect landmark ID Incorrect angle Unable to cannulate on first attempt Average sticks to cannulation Unable to pass line over wire
Standard (%) n ⫽ 39 3/39 2/39 7/39 4/39
(7.7) (5.1) (17.9) (10.3)
5/39 (12.8) 1/39 (2.6) 9/39 (23) 27/39 (69.2)
Simulated (%) n ⫽ 34 3/34 1/34 2/34 3/34
(8.8) (2.9) (5.8) (8.8)
6/34 (17.6) 0/34 (0) 5/34 (15) 17/34 (50)
P .80 .91 .22 .86 .81 .96 .55 .15
2.59 (1.41)
2.41 (1.86)
.64
12/39 (30.8)
8/43 (23.5)
.66
but 1 of the lines that the study subjects were not able to do. One line was attempted unsuccessfully by the attending after failed attempts by all the trainees. The overall performance of the simulated group was superior to the standard group in both performance and avoidance of complications (Table 5). During the simulated months, there were 8 line infections and 495 line days. Four of the bloodstream infections occurred in patients with lines not placed as part of the study (1 tunneled dialysis catheter and 3 lines placed outside of the ICU). The remaining 4 infections were in lines place by the simulated group, with 480 line days and .008 infections/ line day. The standard group had 3 line infections in 595 line days and .005 infections/line day (P ⫽ .8).
Comments Simulation for central line placement using the CentralLineMan partial-task simulator did positively affect resident performance on patients. This was particularly significant with regard to line complications. Complications from
Table 4
Complications
Complications Arterial puncture Need for senior resident to take over Inability to place line Pneumothorax Blood stream infection Improper line position on x-ray
Standard (%) n ⫽ 39 1/39 (2.6)
Simulated (%) n ⫽ 34 0/34 (0)
P .96
22/39 (56) 11/39 (28.2) 4/39 (10)
12/34 (35) 5/34 (14.7) 0/34 (0)
.11 .25 .17
3/39 (7.7)
4/34 (11.8)
.84
2/39 (5.1)
3/34 (8.8)
.87
Summary of performance
Performance element
Standard (%)
Simulated (%)
P
Performance errors Complications
70/351 (19.9) 43/195 (22.1)
45/306 (14.7) 24/170 (14.1)
.09 .07
central lines contribute significantly to increased health care costs. Although catheter-related infection contributes significantly to hospital charges, averaging in 1 study 43% of the total hospital cost,11 simulation does not appear to significantly alter infection risk. Pneumothorax is a significant morbidity related to central line placement and a potential source of mortality if not recognized. We believe that the simulator allows for teaching appropriate angle of approach with the needle and results in decreased risk of pneumothorax. In addition, although these did not reach statistical significance, we were encouraged by the decrease in arterial puncture, the need for senior resident intervention, and inability to place the line in the simulated group. The traditional model in our hospital was for residents to be considered “signed off” on central lines after being monitored for 5 consecutive internal jugular and subclavian lines. We considered the need for a senior resident to take over the line as a complication because we were attempting to clarify junior resident ability to safely place a line. When analyzing the complication data without including the need for senior resident to take over the procedure, we still saw a trend toward improvement in the simulated group. From our observations, we have implemented a mandatory central line simulation curriculum for our junior residents they performance procedures on any patients. In addition, we implemented mandatory observation by an attending surgeon of line performance before residents were allowed to do any central lines unsupervised. The most significant findings in the study relate to increased resident comfort and ability in the simulated group. One of the main goals of residency training programs is to train residents to be both confident and competent when performing procedural skills. Learners with increased self-efficacy (belief in their ability to accomplish a particular task) demonstrate higher achievement.12 The fact that residents in the simulated group also demonstrated improvement over those in the standard group on 7 of 10 performance measures is encouraging as we continue to move toward proficiency training for surgical skills in residency programs. Despite the prospective, randomized design, this study is associated with some limitations that may have impacted the outcomes. First, we were unable to record any patient data, such as reason for hospitalization, body mass index, and other patient-specific factors, clearly impacting central line placement performance because of limitations imposed by our IRB. We attempted to control for this by our randomization procedure and by monitoring as many line performances as possible by each resident, but this remains a limit to the study. Second, the evaluators were not blinded
536 to the groups, which certainly could introduce bias. We attempted to control for variability among the evaluators by only allowing 2 surgeons to evaluate the performance and by using an objective structured checklist. Last, because we randomized groups on a month-to-month basis and because there were a different number of residents rotating per month, we did not have the same number of subjects in the 2 groups. Concerns with simulation include whether the learner “buys into” the model and how well the models are able to simulate the procedural steps. The current models allow for teaching both subclavian and internal jugular line placement and include the use of US. Our institution previously reported that central line simulation was believed by residents to be beneficial and rated the current model in use an average of 4.5 out of 5 points for realism.13 Certainly, as the models continue to evolve they will become more realistic. We chose not to incorporate US training into this study, but we are assessing the addition of this modality to our standard training. No proficiency standard currently exists for training on the central line partial-task simulator. Work is currently underway to establish proficiency standards for training, which will likely lead to even more significant improvement in performance for the simulated trainee.
References 1. Huang GC, Smith CC, Gordon GE, et al. Beyond the comfort zone: residents assess their comfort performing inpatient medical procedures. Am J Med 2006;119:e17– e24.
The American Journal of Surgery, Vol 197, No 4, April 2009 2. Van Sickle KR, Ritter EM, Smith CD. The pretrained novice: using simulation-based training to improve learning in the operating room. Surg Innov 2006;13:198 –204. 3. Seymour NE, Gallagher AG, Roman SA, et al. Virtual reality training improves operating room performance: results of a randomized, double-blinded study. Ann Surg 2002;236:458 – 64. 4. Hsu JH, Younan D, Pandalai S, et al. Use of computer simulation for determining endovascular skill levels in a carotid stenting model. J Vasc Surg 2004;40:1118 –25. 5. Ramakrishna G, Higano ST, McDonald FS, et al. A curricular initiative for internal medicine residents to enhance proficiency in internal jugular central venous line placement. Mayo Clin Proc 2005;80: 212– 8. 6. Velmahos GC, Toutouzas KG, Sillin LF, et al. Cognitive task analysis for teaching technical skills in an inanimate surgical skill laboratory. Am J Surg 2004;187:114 –9. 7. Sherertz RJ, Ely EW, Westbrook DM, et al. Education of physiciansin-training can decrease the risk for vascular catheter infection. Ann Intern Med 2000;132:641– 8. 8. Eggimann P, Harbath S, Constantin MN, et al. Impact of a prevention strategy targeted at vascular-access care on incidence of infections acquired in intensive care. Lancet 2000;355:1864 – 8. 9. Charlambous C, Swoboda SM, Dick J, et al. Risk factors and clinical impact of central line infections in the surgical intensive care unit. Arch Surg 1998;133:1241– 6. 10. Merrer J, De Jonghe B, Golliot F, et al. Complications of femoral and subclavian venous catheterization in critically ill patients: A randomized controlled trial. JAMA 2001;286:700 –7. 11. Shannon RP, Patel B, Shannon AH, et al. Economics of central-line associated bloodstream infections. Am J Med Qual 2006;21(Suppl): 7S–16S. 12. Bandura A. Self-efficacy: the exercise of control. New York, NY: W. H. Freeman; 1997. 13. Britt RC, Reed SF, Britt LD. Central line simulation: A new training algorithm. Am Surg 2007;73:680 –2.