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Microdebrider tonsillectomy associated with more intraoperative blood loss than electrocautery
International Journal of Pediatric Otorhinolaryngology 76 (2012) 1437–1441
Contents lists available at SciVerse ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Microdebrider tonsillectomy associated with more intraoperative blood loss than electrocautery Kyle J. Stansifer a,*, Molly G. Szramowski b, Lindsay Barazsu c, Farrel J. Buchinsky d,a a
Temple University School of Medicine, Philadelphia, PA, USA Allegheny General Hospital, Pittsburgh, PA, USA c University of Michigan, Ann Arbor, MI, USA d Pediatric Otolaryngology, Allegheny General Hospital, Pittsburgh, PA, USA b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 19 April 2012 Received in revised form 18 June 2012 Accepted 20 June 2012 Available online 15 July 2012
Objective: To describe and compare the intraoperative blood loss in children who underwent tonsillectomy and/or adenoidectomy during a transition from using electrocautery to a microdebrider. Methods: Retrospective case series of a single pediatric otolaryngologist at an urban general hospital. Patients aged 2–20 years who had tonsillectomy, adenoidectomy, or adenotonsillectomy over a 12 month period were included. Tonsillectomy was performed by microdebrider or electrocautery and adenoidectomy was performed by microdebrider, curette, or suction electrocautery. Total intraoperative blood loss was measured and compared between surgical techniques. Results: Of the 148 patients, 109 had tonsillectomy with or without adenoidectomy and 39 had adenoidectomy alone. The mean blood loss was 47 ml or 1.8 1.6 ml/kg and the maximum blood loss was 11 ml/kg. Adenoid curette and adenoid microdebrider yielded similar blood loss but were associated with more bleeding than suction electrocautery (P < 0.05). Microdebrider tonsillectomy yielded more blood loss than electrocautery tonsillectomy (mean of 2.6 2.2 ml/kg versus 1.2 1.2 ml/kg, P = 0.0002). Eighteen percent of adenotonsillectomy patients lost greater than 5% of calculated circulating blood volume (95% CI, 9.8–26). Linear regression models did not show an association between the amount of blood loss and patient age, clinical indication, or the surgeon’s experience with the microdebrider (P > 0.05). Conclusions: Microdebrider tonsillectomy is associated with more intraoperative bleeding than electrocautery tonsillectomy. Approximately twice as much blood was lost with the microdebrider, but the absolute increase was insignificant from a hemodynamic perspective. ß 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Tonsillectomy Partial intracapsular tonsillectomy Adenoidectomy Microdebrider Electrocautery Pediatrics
1. Introduction Tonsillectomy and adenoidectomy are very commonly performed surgeries, and the techniques continue to evolve. A few decades ago there was a shift from cold dissection to electrocautery when the latter was shown to incur lower intraoperative blood loss [1]. Electrocautery, however, has long since been associated with more postoperative pain due to thermal injury of tissue. While the surgery remains common, the clinical indication has changed over time. A large cross-sectional survey showed that from 1970 to 2005 the incidence of tonsillectomy and adenotonsillectomy increased, and the indication shifted from infection to upper airway obstruction [2]. The most common etiology of
* Corresponding author at: 981225 Nebraska Medical Center, Omaha, NE 681981225, USA. Tel.: +402 559 8007; fax: +402 559 8940. E-mail address: [email protected] (K.J. Stansifer). 0165-5876/$ – see front matter ß 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijporl.2012.06.018
airway obstruction, or sleep-disordered breathing (SDB), in children is hyperplasia of the tonsils and adenoids [3]. Power-assisted adenoidectomy was described in 1997 and partial intracapsular tonsillectomy in 2002 for patients with SDB [4,5]. The microdebrider removes tissue with a rapidly rotating blade that suctions out excised tissue while preserving the tonsillar capsule, which functions as a biological membrane. Many studies have compared microdebrider to standard total tonsillectomy by electrocautery. The microdebrider has been shown to minimize the adverse effects of the surgery: less postoperative pain, reduced duration of analgesic use, quicker return to normal activity and diet, and reduced incidence of otalgia [5–11]. Although it leaves a small amount of residual tonsil tissue [8], tonsillar regrowth is a rare complication. Furthermore, removing the bulk of the tissue relieves SDB as effectively as total tonsillectomy does [5,12]. In 2007 the senior author switched to the microdebrider for tonsillectomy and adenoidectomy. Prior to 2007, adenoids were removed by adenoid curette and tonsils by electrocautery. Over the
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initial months of microdebrider use, the surgeon and surgical technicians perceived greater intraoperative blood loss with microdebrider tonsillectomies. The perception continued for 9 months. Dissatisfied with the microdebrider for tonsillectomies, the surgeon switched back to electrocautery. However, he continued with microdebrider adenoidectomies given the perception that the two adenoid methods led to similar blood loss. Perceptions (even in surgeons) are susceptible to multiple human illusions [13]. Given that data had already been recorded, we undertook a data analysis to confirm or refute our suspicion that microdebrider tonsillectomy is associated with more intraoperative blood loss than electrocautery tonsillectomy. The aim of this study was to contrast the intraoperative blood loss from tonsillectomy by electrocautery versus microdebrider and to describe similar contrasts for adenoidectomy by curette, microdebrider, and suction electrocautery. Finally, we wanted to quantitate blood loss as a function of patient circulating blood volume in order to view it in the clinical context of hemodynamics.
2. Methods This study was reviewed and approved by the Allegheny General Hospital Institutional Review Board. 2.1. Participants We performed a retrospective review of all patients who underwent tonsillectomy and/or adenoidectomy by a single ENT surgeon at the Allegheny General Hospital in Pittsburgh, PA between September 2007 and August 2008. Clinical indications included airway obstruction (SDB or mouth breathing) and/or chronic infection including adenoiditis, tonsillitis and/or otitis media. In 2007 the surgeon switched to the microdebrider technique for adenoids and tonsils, however electrocautery was not completely abandoned since there were days in which the microdebrider was not available in the operating room. Although the patients were not randomized, data exist to compare one method to another with the realistic expectation that there was no systemic difference between the patients undergoing the two types of adenotonsillectomy. 2.2. Surgical techniques All surgical procedures were performed by a single ENT surgeon (F.J.B.). Patients were instructed to not take aspirin or ibuprofen for 2 weeks before and after surgery. After induction with sevoflurane, all patients were administered corticosteroids (dexamethasone, 0.15 mg/kg). The surgeon does not use local anesthetic. Orotracheal intubation was performed with the patient in the Rose position. A McIvor or a Crowe–Davis gag retractor was placed and two red rubber catheters were used to elevate the palate. Adenoidectomy was performed when clinically indicated by one of the following techniques: power-assisted microdebrider with a 408 curved PITATM Blade on a Straightshot1 M4 Microdebrider (Medtronic, Minneapolis, MN, USA) set at 1500 rpm on oscillating mode or curettage with an adenoid curette followed by St. Clair Thomson forceps to remove residual adenoidal tissue. The nasopharynx was then packed tightly with cotton sponges to tamponade bleeding. Fulguration of residual adenoidal tissue and final hemostasis in the nasopharynx was accomplished with suction electrocautery set at 40 W. A third adenoidectomy technique, suction electrocautery at 45 W, was occasionally used when the adenoids were relatively small. The adenoidal tissue was liquefied and suctioned out using a back and forth motion.
Tonsillectomy began with the right tonsil followed by the left tonsil. Power-assisted microdebrider tonsillectomy was performed with a 128 PITATM Blade on a Straightshot1 M4 Microdebrider (Medtronic, Minneapolis, MN, USA) set at 1500 rpm on oscillating mode. Tonsils were excised from the inferior to superior pole in a medial to lateral fashion. Tonsils were stabilized with a hurd retractor to allow debridement until the stringy material of the peritonsillar capsule was encountered. Electrocautery tonsillectomy was performed with an EDGETM coated needle electrode (E1465, Valleylab, Boulder, CO, USA) pencil tip bovie set at 15 W. Following tonsillectomy, suction electrocautery at 25 W was used to ensure hemostasis. In cases where the surgeon subjectively experienced unusually brisk bleeding during the microdebrider tonsillectomy, it was his practice to switch to electrocautery for the remaining (left) tonsil. The nasopharynx and orophaynx were irrigated with saline at the end of the case. Final intraoperative blood loss was measured in a Medi-Vac1 Critical Measurement Unit (Cardinal Health, Dublin, OH) prior to irrigation. If tonsillectomy or adenoidectomy was performed by microdebrider, the tissue was suctioned off along with any blood loss. Measured blood loss was adjusted by the volume of the debrided lymphoid tissue. 2.3. Outcome measures The data collected included patient’s age, gender, weight (kg), race, date of service, clinical indication(s), and surgical technique(s). The primary outcome was measured intraoperative blood loss expressed in volume (ml) per body mass (kg). The secondary outcome was the frequency of measured intraoperative blood loss equaling or exceeding 5% of calculated circulating blood volume; the surgeon’s practice is to admit patients who lose 10% estimated blood volume or more to monitor their hemodynamic status. 2.4. Statistical analysis The main outcome was measured blood loss while accounting for the estimated adenoid or tonsillar volume in the suction trap for microdebrider cases. Blood loss was analyzed principally as volume per body mass. Adjusted blood loss (without dividing by body mass) is also included for comparison to other publications. A hierarchical ANOVA model (R statistical software (http:// www.r-project.org/)) examined the variance in blood loss associated with two factors: (1) adenoidectomy factor (with 4 levels: microdebrider, adenoid curette, suction electrocautery, no adenoidectomy); (2) tonsillectomy factor (with 3 levels: electrocautery, microdebrider, no tonsillectomy). A hierarchical model accounts for the variance associated with the adenoidectomy method (without controlling for any association with the tonsillectomy method) before determining if there is any variance associated with the tonsillectomy method. Since the ANOVA model showed statistical significance (P < 0.05) for each factor, Tukey’s honestly significant difference (HSD) post hoc tests were performed to identify which differences between methods were statistically significant. Within the analysis, the tonsillectomy method attributed to each individual patient was the method used on the first (right) tonsil regardless of whether or not the surgeon switched to a different method for the second tonsil. Changing tonsil technique occurred only when there was excessive blood loss during excision of the first tonsil. Thus, the design of the analysis was on the basis of intention to treat and therefore ignored the effects of crossover. Estimated circulating blood volume was calculated as 70 ml/kg [14]. Patient age, clinical indication, and date of service (as a proxy for surgeon’s experience with microdebrider) were analyzed as
K.J. Stansifer et al. / International Journal of Pediatric Otorhinolaryngology 76 (2012) 1437–1441
independent variables. Multiple linear regression models were used. Fisher exact test was used to compare the proportion of microdebrider versus electrocautery patients who lost more than 5% of circulating blood volume. 3. Results A total of 148 patients were included in our study, and demographics are given in Table 1. One hundred and nine patients had tonsillectomy (with or without adenoidectomy), and 39 had adenoidectomy alone. Forty two patients underwent tonsillectomy by microdebrider and 67 by electrocautery. In 5 of the 42 microdebrider tonsillectomy patients, the surgeon perceived heavy intraoperative blood loss and switched to electrocautery for the remaining left tonsil. One of the 67 electrocautery tonsillectomy patients experienced heavy intraoperative blood loss, and the surgeon elected not to excise the contralateral tonsil. Blood loss for all techniques is summarized in Table 2. Only one blood loss measurement was recorded for each patient after their operation. Adenoid and tonsil bleeding were subsequently separated by statistical techniques applied to group means by hierarchical ANOVA. The mean blood loss standard deviation was 1.8 1.6 ml/ kg. For excision of the adenoids, adenoid curette and adenoid microdebrider were each associated with more blood loss than suction electrocautery (1.5 ml/kg more, P = 0.04; 1.9 ml/kg more, P = 0.002, respectively). However, there was no significant difference between adenoid curette and adenoid microdebrider (P = 0.67).
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Table 1 Patient demographics. Number of patients Gender Race Age Weight Indication
148 Male = 73 (49%), female = 75 (51%) Caucasian = 126 (85%), African American = 22 (15%) Median = 6.8 years, range = 2.2–20.6 years Median = 24 kg, range = 11–100 kg Airway obstruction = 61 (41%), chronic infection = 53 (36%), both = 34 (23%)
A comparison of intraoperative blood losses for adenoid and tonsil techniques are given in Table 3. After statistically controlling for adenoid methods, the ANOVA model showed that microdebrider tonsillectomy was associated with 1.2 ml/kg more blood loss than electrocautery tonsillectomy (P = 0.0002). Pooling all adenoidectomy methods, blood loss was 2.6 2.2 ml/kg for those who underwent microdebrider tonsillectomy and 1.2 1.2 ml/kg for those who underwent electrocautery tonsillectomy. The maximum blood loss was 11.0 ml/kg for microdebrider and 4.5 ml/kg for electrocautery. A cut off of 5% of calculated circulating blood volume was used to determine which patients were progressing toward clinically significant intraoperative blood loss. Overall, 18 (12%) of the 148 patients lost greater than 5% blood volume (95% CI, 6.9–17). Since this 148 pools adenotonsillectomy, tonsillectomy, and adenoidectomy together, we did a subset analysis and found that 18% of adenotonsillectomy patients lost greater than 5% blood volume (95% CI, 9.8–26).
Table 2 Intraoperative blood loss for 148 children undergoing adenoid and/or tonsil surgery divided by two factors: adenoid technique in rows and intended tonsil technique by columns. For each cell, the aggregated data (shaded boxes) of the sample size and mean blood loss (in ml and in ml/kg standard deviation) are stated. The same data is noted in the margins (clear boxes) for each level of each factor.
Planned tonsil technique Adenoid technique Not done
n Blood loss Blood loss per body weight and sd
Suction electrocautery
Not done
n=0
n=0
Microdebrider Electrocautery
n=7 26 ml 1.0 ± 0.8 ml/kg
n = 10 6.0 ml 0.1 ± 0.1 ml/kg
n=1 60 ml
n=7 7 ml 0.1 ± 0.1 ml/kg
n=8 13 ml
n = 19 48 ml 1.7 ± 1.2 ml/kg
n = 24 48 ml
n = 31 56 ml 1.6 ± 1.3 ml/kg
n = 99 54 ml
0.8 ml/kg Adenoid curette
Microdebrider
Average for adenoid technique n = 17 14 ml
n=5 50 ml 2.1 ± 1.0 ml/kg
n=0
n = 34 35 ml 1.7 ± 1.1 ml/kg
n = 34 73 ml 3.0 ± 2.2 ml/kg
0.5 ± 0.7 ml/kg
0.2 ± 0.3 ml/kg
1.7 ± 1.1 ml/kg
2.1 ± 1.7 ml/kg All patients
Average for tonsil technique
n = 39 37 ml 1.7 ± 1.1 ml/kg
n = 42 64 ml 2.6 ± 2.2 ml/kg
n = 67 41 ml 1.2 ± 1.2 ml/kg
n = 148 47 ml 1.8 ± 1.6 ml/kg
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Table 3 Tukey’s honestly significant difference (HSD) post hoc tests following statistically significant ANOVA comparison of intraoperative blood loss for adenoid and tonsil techniques.
Adenoidectomy BL (ml/kg)
Tonsillectomy BL (ml/kg)
Technique
Versus technique
Suction electrocautery Adenoid curette Microdebrider Adenoid curette Microdebrider Microdebrider
No adenoidectomy No adenoidectomy No adenoidectomy Suction electrocautery Suction electrocautery Adenoid curette
0.3 1.3 1.6 1.5 1.9 0.4
Electrocautery Microdebrider Microdebrider
No tonsillectomy No tonsillectomy Electrocautery
Linear regression models were used to analyze whether age, clinical indication (airway obstruction or chronic infection), or surgical experience/date of surgery were correlated with blood loss when controlling for surgical method. There was no association between any of these variables and blood loss (P > 0.05).
4. Discussion Our results demonstrate that microdebrider tonsillectomy (with or without adenoidectomy) is associated with greater intraoperative blood loss than electrocautery tonsillectomy in children. Four prospective studies [8,9,11,15] and one retrospective study [10] found similar results to ours. Although we did not record blood lost during adenoidectomy versus tonsillectomy portions of an adenotonsillectomy, we were able to mathematically determine the amount of blood lost from each of the composite procedures. While Koltai et al. [5,6] found no significant difference between microdebrider and electrocautery blood loss, they noted that microdebrider bleeding had the potential to obscure tissue specificity and thereby risk injury to the pharyngeal musculature. The operating surgeon in Bitar’s study [9] as well as in our study also noted poor tissue visibility due to bleeding while performing the microdebrider tonsillectomy. It remains imperative to maintain a proper view of the operative field throughout the surgery. Traditional adenoid curette has been shown to produce more blood loss than suction electrocautery [16] and it may or may not produce more blood loss than microdebrider [17,18]. Our results show that adenoid curette and microdebrider are each associated with more blood loss than suction electrocautery. Like Rodriguez et al. [18], we found no difference between curette and microdebrider. Significant learning curves have been noted with the microdebrider [9,10]. While it was a new technique for our surgeon, the linear regression model showed that microdebrider tonsillectomy blood loss did not statistically change over our 9 month study period. We found that a higher proportion of adenotonsillectomy patients (18%) versus the group as a whole (12%) lost greater than 5% of calculated circulating blood volume. This is due to the additive loss of the tonsils and adenoids. While 5% is a relatively low blood volume that can be replaced easily with crystalloid intravenous infusion, ‘‘5%’’ can serve as a marker for progression toward higher losses. Estimated blood volume for children is 70 ml/kg [14]. Thus only when blood loss approaches 28 ml/kg (40%) does an intervention such as a blood transfusion need to be considered. Because a small percentage of patients could have a postoperative hemorrhage, it would be prudent to keep losses well below 28 ml/kg. Therefore, one may consider the 1.2 ml/kg extra blood loss associated with the microdebrider to be irrelevant.
Difference (ml/kg)
P value
95% CI
(curette more) (microdebrider more) (curette more) (microdebrider more)
0.99 0.03 0.0001 0.04 0.002 0.67
1.8, 0.1, 0.7, 0.0, 0.5, 0.5,
0 1.2 1.2 (microdebrider more)
0.99 0.0007 0.0002
0.6, 0.7 0.4, 1.9 0.5, 1.8
1.3 2.4 2.6 3.0 3.2 1.2
It is essential to consider the risk of postoperative hemorrhage. Large retrospective comparative studies have shown that microdebrider postoperative hemorrhage rates are significantly lower at 0.4–1.1% versus electrocautery rates of 1.9–6.8% [19– 21]. So while the microdebrider is associated with increased blood loss, one could argue for its use because of its lower postoperative hemorrhage risk. Furthermore, most studies show that microdebrider is superior to electrocautery for postoperative pain, length of analgesic use, and return to normal activity and diet [5–11]. Our data are strong in that we had only one operating surgeon, which allowed us to control for surgical technique without having to consider inter-surgeon variability. We also adjusted for the tonsil and adenoid volumes that were suctioned into the blood collection traps and would have artificially raised the measured blood loss. The review of our data was not designed as a prospective interventional study which means the surgical techniques were not randomized. We therefore cannot assume that the microdebrider and electrocautery groups were identical. The surgeon, surgical technicians, and statistical analyst were not blinded to the interventions and thus bias may exist. In conclusion, our suspicion that microdebrider tonsillectomies result in more intraoperative blood loss than electrocautery tonsillectomies was confirmed. By the time the statistical analysis was performed, the surgeon had already rejected the microdebrider for tonsillectomy (but had continued to use it for adenoidectomy). Notwithstanding, the quantity of increased blood loss was not hemodynamically significant. Despite the numeric insight, the surgeon did not return to using the microdebrider since the increased bleeding decreased visibility in the operative field. The surgeon still uses the microdebrider for adenoidectomies where the blood loss is similar to the adenoid curette. Authorship All authors have read, approved, and made significant contributions toward the article. Data access and responsibility Farrel J. Buchinsky had full access to all data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Conflict of interest None (for all authors). Poster presentation This paper was presented as a poster at the AAO-HNSF Annual Meeting and Oto Expo in September, 2011:Stansifer KJ,
K.J. Stansifer et al. / International Journal of Pediatric Otorhinolaryngology 76 (2012) 1437–1441
Szramowski MG, Barazsu L, Post JC, Buchinsky FJ. Adenotonsillectomy bleeding: microdebrider vs. electrocautery. American Academy of Otolaryngology – Head and Neck Surgery Foundation Annual Meeting and Oto Expo, San Francisco, CA, USA, September 11–14, 2011. References [1] T.A. Weimert, J.W. Babyak, H.J. Richter, Electrodissection tonsillectomy, Arch. Otolaryngol. Head Neck Surg. 116 (2) (1990) 186–188. [2] B.K. Erickson, D.R. Larson, J.L. St Sauver, R.A. Meverden, L.J. Orvidas, Changes in incidence and indications of tonsillectomy and adenotonsillectomy, 1970–2005, Otolaryngol. Head Neck Surg. 140 (6) (2009) 894–901. [3] D.H. Darrow, Surgery for pediatric sleep apnea, Otolaryngol. Clin. North Am. 40 (4) (2007) 855–875. [4] P.J. Koltai, A.S. Kalathia, P. Stanislaw, H.A. Heras, Power-assisted adenoidectomy, Arch. Otolaryngol. Head Neck Surg. 123 (7) (1997) 685–688. [5] P.J. Koltai, C.A. Solares, E.J. Mascha, M. Xu, Intracapsular partial tonsillectomy for tonsillar hypertrophy in children, Laryngoscope 112 (8 (Pt 2 (Suppl. 100))) (2002) 17–19. [6] P.J. Koltai, C.A. Solares, J.A. Koempel, K. Hirose, T.I. Abelson, P.R. Krakovitz, et al., Intracapsular tonsillar reduction (partial tonsillectomy): reviving a historical procedure for obstructive sleep disordered breathing in children, Otolaryngol. Head Neck Surg. 129 (5) (2003) 532–538. [7] M.T. Lister, M.J. Cunningham, B. Benjamin, M. Williams, A. Tirrell, D.A. Schaumberg, et al., Microdebrider tonsillectomy vs. electrosurgical tonsillectomy: a randomized, double-blind, paired control study of postoperative pain, Arch. Otolaryngol. Head Neck Surg. 132 (6) (2006) 599–604. [8] C.S. Derkay, D.H. Darrow, C. Welch, J.T. Sinacori, Post-tonsillectomy morbidity and quality of life in pediatric patients with obstructive tonsils and adenoid: microdebrider vs. electrocautery, Otolaryngol. Head Neck Surg. 134 (1) (2006) 114–120. [9] M.A. Bitar, C. Rameh, Microdebrider-assisted partial tonsillectomy: short- and long-term outcomes, Eur. Arch. Otorhinolaryngol. 265 (4) (2008) 459–463.
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[10] C.M. Mixson, P.M. Weinberger, M.B. Austin, Comparison of microdebrider subcapsular tonsillectomy to harmonic scalpel and electrocautery total tonsillectomy, Am. J. Otolaryngol. 28 (1) (2007) 13–17. [11] S.E. Sobol, R.F. Wetmore, R.R. Marsh, J. Stow, I.N. Jacobs, Postoperative recovery after microdebrider intracapsular or monopolar electrocautery tonsillectomy: a prospective, randomized, single-blinded study, Arch. Otolaryngol. Head Neck Surg. 132 (3) (2006) 270–274. [12] C.A. Solares, J.A. Koempel, K. Hirose, T.I. Abelson, J.S. Reilly, S.P. Cook, et al., Safety and efficacy of powered intracapsular tonsillectomy in children: a multi-center retrospective case series, Int. J. Pediatr. Otorhinolaryngol. 69 (1) (2005) 21–26. [13] C. Chabris, D. Simons, The Invisible Gorilla: How Our Intuitions Deceive Us, 1st ed., Crown Publishing Group, New York, NY, 2010. [14] C.T. Albanese, K.G. Sylvester, Pediatric surgery, in: G.M. Doherty (Ed.), Current Diagnosis & Treatment: Surgery, 13th ed., McGraw-Hill, New York, 2010, , http:// www.accesssurgery.com. March 11, 2012 (Chapter 43). [15] C.V. Nguyen, S.R. Parikh, J.P. Bent, Comparison of intraoperative bleeding between microdebrider intracapsular tonsillectomy and electrocautery tonsillectomy, Ann. Otol. Rhinol. Laryngol. 118 (10) (2009) 698–702. [16] J. Clemens, J.S. McMurray, J.P. Willging, Electrocautery versus curette adenoidectomy: comparison of postoperative results, Int. J. Pediatr. Otorhinolaryngol. 43 (2) (1998) 115–122. [17] P. Stanislaw Jr., P.J. Koltai, P.J. Feustel, Comparison of power-assisted adenoidectomy vs adenoid curette adenoidectomy, Arch. Otolaryngol. Head Neck Surg. 126 (7) (2000) 845–849. [18] K. Rodriguez, N. Murray, J.L. Guarisco, Power-assisted partial adenoidectomy, Laryngoscope 112 (8 (Pt 2 (Suppl. 100))) (2002) 26–28. [19] T.Q. Gallagher, L. Wilcox, E. McGuire, C.S. Derkay, Analyzing factors associated with major complications after adenotonsillectomy in 4776 patients: comparing three tonsillectomy techniques, Otolaryngol. Head Neck Surg. 142 (6) (2010) 886–892. [20] K. Gan, C. Tomlinson, H. El-Hakim, Post-operative bleeding is less after partial intracapsular tonsillectomy than bipolar total procedure, Int. J. Pediatr. Otorhinolaryngol. 73 (5) (2009) 667–670. [21] R. Schmidt, A. Herzog, S. Cook, R. O’Reilly, E. Deutsch, J. Reilly, et al., Complications of tonsillectomy: a comparison of techniques, Arch. Otolaryngol. Head Neck Surg. 133 (9) (2007) 925–928.
Contents lists available at SciVerse ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Microdebrider tonsillectomy associated with more intraoperative blood loss than electrocautery Kyle J. Stansifer a,*, Molly G. Szramowski b, Lindsay Barazsu c, Farrel J. Buchinsky d,a a
Temple University School of Medicine, Philadelphia, PA, USA Allegheny General Hospital, Pittsburgh, PA, USA c University of Michigan, Ann Arbor, MI, USA d Pediatric Otolaryngology, Allegheny General Hospital, Pittsburgh, PA, USA b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 19 April 2012 Received in revised form 18 June 2012 Accepted 20 June 2012 Available online 15 July 2012
Objective: To describe and compare the intraoperative blood loss in children who underwent tonsillectomy and/or adenoidectomy during a transition from using electrocautery to a microdebrider. Methods: Retrospective case series of a single pediatric otolaryngologist at an urban general hospital. Patients aged 2–20 years who had tonsillectomy, adenoidectomy, or adenotonsillectomy over a 12 month period were included. Tonsillectomy was performed by microdebrider or electrocautery and adenoidectomy was performed by microdebrider, curette, or suction electrocautery. Total intraoperative blood loss was measured and compared between surgical techniques. Results: Of the 148 patients, 109 had tonsillectomy with or without adenoidectomy and 39 had adenoidectomy alone. The mean blood loss was 47 ml or 1.8 1.6 ml/kg and the maximum blood loss was 11 ml/kg. Adenoid curette and adenoid microdebrider yielded similar blood loss but were associated with more bleeding than suction electrocautery (P < 0.05). Microdebrider tonsillectomy yielded more blood loss than electrocautery tonsillectomy (mean of 2.6 2.2 ml/kg versus 1.2 1.2 ml/kg, P = 0.0002). Eighteen percent of adenotonsillectomy patients lost greater than 5% of calculated circulating blood volume (95% CI, 9.8–26). Linear regression models did not show an association between the amount of blood loss and patient age, clinical indication, or the surgeon’s experience with the microdebrider (P > 0.05). Conclusions: Microdebrider tonsillectomy is associated with more intraoperative bleeding than electrocautery tonsillectomy. Approximately twice as much blood was lost with the microdebrider, but the absolute increase was insignificant from a hemodynamic perspective. ß 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Tonsillectomy Partial intracapsular tonsillectomy Adenoidectomy Microdebrider Electrocautery Pediatrics
1. Introduction Tonsillectomy and adenoidectomy are very commonly performed surgeries, and the techniques continue to evolve. A few decades ago there was a shift from cold dissection to electrocautery when the latter was shown to incur lower intraoperative blood loss [1]. Electrocautery, however, has long since been associated with more postoperative pain due to thermal injury of tissue. While the surgery remains common, the clinical indication has changed over time. A large cross-sectional survey showed that from 1970 to 2005 the incidence of tonsillectomy and adenotonsillectomy increased, and the indication shifted from infection to upper airway obstruction [2]. The most common etiology of
* Corresponding author at: 981225 Nebraska Medical Center, Omaha, NE 681981225, USA. Tel.: +402 559 8007; fax: +402 559 8940. E-mail address: [email protected] (K.J. Stansifer). 0165-5876/$ – see front matter ß 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijporl.2012.06.018
airway obstruction, or sleep-disordered breathing (SDB), in children is hyperplasia of the tonsils and adenoids [3]. Power-assisted adenoidectomy was described in 1997 and partial intracapsular tonsillectomy in 2002 for patients with SDB [4,5]. The microdebrider removes tissue with a rapidly rotating blade that suctions out excised tissue while preserving the tonsillar capsule, which functions as a biological membrane. Many studies have compared microdebrider to standard total tonsillectomy by electrocautery. The microdebrider has been shown to minimize the adverse effects of the surgery: less postoperative pain, reduced duration of analgesic use, quicker return to normal activity and diet, and reduced incidence of otalgia [5–11]. Although it leaves a small amount of residual tonsil tissue [8], tonsillar regrowth is a rare complication. Furthermore, removing the bulk of the tissue relieves SDB as effectively as total tonsillectomy does [5,12]. In 2007 the senior author switched to the microdebrider for tonsillectomy and adenoidectomy. Prior to 2007, adenoids were removed by adenoid curette and tonsils by electrocautery. Over the
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initial months of microdebrider use, the surgeon and surgical technicians perceived greater intraoperative blood loss with microdebrider tonsillectomies. The perception continued for 9 months. Dissatisfied with the microdebrider for tonsillectomies, the surgeon switched back to electrocautery. However, he continued with microdebrider adenoidectomies given the perception that the two adenoid methods led to similar blood loss. Perceptions (even in surgeons) are susceptible to multiple human illusions [13]. Given that data had already been recorded, we undertook a data analysis to confirm or refute our suspicion that microdebrider tonsillectomy is associated with more intraoperative blood loss than electrocautery tonsillectomy. The aim of this study was to contrast the intraoperative blood loss from tonsillectomy by electrocautery versus microdebrider and to describe similar contrasts for adenoidectomy by curette, microdebrider, and suction electrocautery. Finally, we wanted to quantitate blood loss as a function of patient circulating blood volume in order to view it in the clinical context of hemodynamics.
2. Methods This study was reviewed and approved by the Allegheny General Hospital Institutional Review Board. 2.1. Participants We performed a retrospective review of all patients who underwent tonsillectomy and/or adenoidectomy by a single ENT surgeon at the Allegheny General Hospital in Pittsburgh, PA between September 2007 and August 2008. Clinical indications included airway obstruction (SDB or mouth breathing) and/or chronic infection including adenoiditis, tonsillitis and/or otitis media. In 2007 the surgeon switched to the microdebrider technique for adenoids and tonsils, however electrocautery was not completely abandoned since there were days in which the microdebrider was not available in the operating room. Although the patients were not randomized, data exist to compare one method to another with the realistic expectation that there was no systemic difference between the patients undergoing the two types of adenotonsillectomy. 2.2. Surgical techniques All surgical procedures were performed by a single ENT surgeon (F.J.B.). Patients were instructed to not take aspirin or ibuprofen for 2 weeks before and after surgery. After induction with sevoflurane, all patients were administered corticosteroids (dexamethasone, 0.15 mg/kg). The surgeon does not use local anesthetic. Orotracheal intubation was performed with the patient in the Rose position. A McIvor or a Crowe–Davis gag retractor was placed and two red rubber catheters were used to elevate the palate. Adenoidectomy was performed when clinically indicated by one of the following techniques: power-assisted microdebrider with a 408 curved PITATM Blade on a Straightshot1 M4 Microdebrider (Medtronic, Minneapolis, MN, USA) set at 1500 rpm on oscillating mode or curettage with an adenoid curette followed by St. Clair Thomson forceps to remove residual adenoidal tissue. The nasopharynx was then packed tightly with cotton sponges to tamponade bleeding. Fulguration of residual adenoidal tissue and final hemostasis in the nasopharynx was accomplished with suction electrocautery set at 40 W. A third adenoidectomy technique, suction electrocautery at 45 W, was occasionally used when the adenoids were relatively small. The adenoidal tissue was liquefied and suctioned out using a back and forth motion.
Tonsillectomy began with the right tonsil followed by the left tonsil. Power-assisted microdebrider tonsillectomy was performed with a 128 PITATM Blade on a Straightshot1 M4 Microdebrider (Medtronic, Minneapolis, MN, USA) set at 1500 rpm on oscillating mode. Tonsils were excised from the inferior to superior pole in a medial to lateral fashion. Tonsils were stabilized with a hurd retractor to allow debridement until the stringy material of the peritonsillar capsule was encountered. Electrocautery tonsillectomy was performed with an EDGETM coated needle electrode (E1465, Valleylab, Boulder, CO, USA) pencil tip bovie set at 15 W. Following tonsillectomy, suction electrocautery at 25 W was used to ensure hemostasis. In cases where the surgeon subjectively experienced unusually brisk bleeding during the microdebrider tonsillectomy, it was his practice to switch to electrocautery for the remaining (left) tonsil. The nasopharynx and orophaynx were irrigated with saline at the end of the case. Final intraoperative blood loss was measured in a Medi-Vac1 Critical Measurement Unit (Cardinal Health, Dublin, OH) prior to irrigation. If tonsillectomy or adenoidectomy was performed by microdebrider, the tissue was suctioned off along with any blood loss. Measured blood loss was adjusted by the volume of the debrided lymphoid tissue. 2.3. Outcome measures The data collected included patient’s age, gender, weight (kg), race, date of service, clinical indication(s), and surgical technique(s). The primary outcome was measured intraoperative blood loss expressed in volume (ml) per body mass (kg). The secondary outcome was the frequency of measured intraoperative blood loss equaling or exceeding 5% of calculated circulating blood volume; the surgeon’s practice is to admit patients who lose 10% estimated blood volume or more to monitor their hemodynamic status. 2.4. Statistical analysis The main outcome was measured blood loss while accounting for the estimated adenoid or tonsillar volume in the suction trap for microdebrider cases. Blood loss was analyzed principally as volume per body mass. Adjusted blood loss (without dividing by body mass) is also included for comparison to other publications. A hierarchical ANOVA model (R statistical software (http:// www.r-project.org/)) examined the variance in blood loss associated with two factors: (1) adenoidectomy factor (with 4 levels: microdebrider, adenoid curette, suction electrocautery, no adenoidectomy); (2) tonsillectomy factor (with 3 levels: electrocautery, microdebrider, no tonsillectomy). A hierarchical model accounts for the variance associated with the adenoidectomy method (without controlling for any association with the tonsillectomy method) before determining if there is any variance associated with the tonsillectomy method. Since the ANOVA model showed statistical significance (P < 0.05) for each factor, Tukey’s honestly significant difference (HSD) post hoc tests were performed to identify which differences between methods were statistically significant. Within the analysis, the tonsillectomy method attributed to each individual patient was the method used on the first (right) tonsil regardless of whether or not the surgeon switched to a different method for the second tonsil. Changing tonsil technique occurred only when there was excessive blood loss during excision of the first tonsil. Thus, the design of the analysis was on the basis of intention to treat and therefore ignored the effects of crossover. Estimated circulating blood volume was calculated as 70 ml/kg [14]. Patient age, clinical indication, and date of service (as a proxy for surgeon’s experience with microdebrider) were analyzed as
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independent variables. Multiple linear regression models were used. Fisher exact test was used to compare the proportion of microdebrider versus electrocautery patients who lost more than 5% of circulating blood volume. 3. Results A total of 148 patients were included in our study, and demographics are given in Table 1. One hundred and nine patients had tonsillectomy (with or without adenoidectomy), and 39 had adenoidectomy alone. Forty two patients underwent tonsillectomy by microdebrider and 67 by electrocautery. In 5 of the 42 microdebrider tonsillectomy patients, the surgeon perceived heavy intraoperative blood loss and switched to electrocautery for the remaining left tonsil. One of the 67 electrocautery tonsillectomy patients experienced heavy intraoperative blood loss, and the surgeon elected not to excise the contralateral tonsil. Blood loss for all techniques is summarized in Table 2. Only one blood loss measurement was recorded for each patient after their operation. Adenoid and tonsil bleeding were subsequently separated by statistical techniques applied to group means by hierarchical ANOVA. The mean blood loss standard deviation was 1.8 1.6 ml/ kg. For excision of the adenoids, adenoid curette and adenoid microdebrider were each associated with more blood loss than suction electrocautery (1.5 ml/kg more, P = 0.04; 1.9 ml/kg more, P = 0.002, respectively). However, there was no significant difference between adenoid curette and adenoid microdebrider (P = 0.67).
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Table 1 Patient demographics. Number of patients Gender Race Age Weight Indication
148 Male = 73 (49%), female = 75 (51%) Caucasian = 126 (85%), African American = 22 (15%) Median = 6.8 years, range = 2.2–20.6 years Median = 24 kg, range = 11–100 kg Airway obstruction = 61 (41%), chronic infection = 53 (36%), both = 34 (23%)
A comparison of intraoperative blood losses for adenoid and tonsil techniques are given in Table 3. After statistically controlling for adenoid methods, the ANOVA model showed that microdebrider tonsillectomy was associated with 1.2 ml/kg more blood loss than electrocautery tonsillectomy (P = 0.0002). Pooling all adenoidectomy methods, blood loss was 2.6 2.2 ml/kg for those who underwent microdebrider tonsillectomy and 1.2 1.2 ml/kg for those who underwent electrocautery tonsillectomy. The maximum blood loss was 11.0 ml/kg for microdebrider and 4.5 ml/kg for electrocautery. A cut off of 5% of calculated circulating blood volume was used to determine which patients were progressing toward clinically significant intraoperative blood loss. Overall, 18 (12%) of the 148 patients lost greater than 5% blood volume (95% CI, 6.9–17). Since this 148 pools adenotonsillectomy, tonsillectomy, and adenoidectomy together, we did a subset analysis and found that 18% of adenotonsillectomy patients lost greater than 5% blood volume (95% CI, 9.8–26).
Table 2 Intraoperative blood loss for 148 children undergoing adenoid and/or tonsil surgery divided by two factors: adenoid technique in rows and intended tonsil technique by columns. For each cell, the aggregated data (shaded boxes) of the sample size and mean blood loss (in ml and in ml/kg standard deviation) are stated. The same data is noted in the margins (clear boxes) for each level of each factor.
Planned tonsil technique Adenoid technique Not done
n Blood loss Blood loss per body weight and sd
Suction electrocautery
Not done
n=0
n=0
Microdebrider Electrocautery
n=7 26 ml 1.0 ± 0.8 ml/kg
n = 10 6.0 ml 0.1 ± 0.1 ml/kg
n=1 60 ml
n=7 7 ml 0.1 ± 0.1 ml/kg
n=8 13 ml
n = 19 48 ml 1.7 ± 1.2 ml/kg
n = 24 48 ml
n = 31 56 ml 1.6 ± 1.3 ml/kg
n = 99 54 ml
0.8 ml/kg Adenoid curette
Microdebrider
Average for adenoid technique n = 17 14 ml
n=5 50 ml 2.1 ± 1.0 ml/kg
n=0
n = 34 35 ml 1.7 ± 1.1 ml/kg
n = 34 73 ml 3.0 ± 2.2 ml/kg
0.5 ± 0.7 ml/kg
0.2 ± 0.3 ml/kg
1.7 ± 1.1 ml/kg
2.1 ± 1.7 ml/kg All patients
Average for tonsil technique
n = 39 37 ml 1.7 ± 1.1 ml/kg
n = 42 64 ml 2.6 ± 2.2 ml/kg
n = 67 41 ml 1.2 ± 1.2 ml/kg
n = 148 47 ml 1.8 ± 1.6 ml/kg
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Table 3 Tukey’s honestly significant difference (HSD) post hoc tests following statistically significant ANOVA comparison of intraoperative blood loss for adenoid and tonsil techniques.
Adenoidectomy BL (ml/kg)
Tonsillectomy BL (ml/kg)
Technique
Versus technique
Suction electrocautery Adenoid curette Microdebrider Adenoid curette Microdebrider Microdebrider
No adenoidectomy No adenoidectomy No adenoidectomy Suction electrocautery Suction electrocautery Adenoid curette
0.3 1.3 1.6 1.5 1.9 0.4
Electrocautery Microdebrider Microdebrider
No tonsillectomy No tonsillectomy Electrocautery
Linear regression models were used to analyze whether age, clinical indication (airway obstruction or chronic infection), or surgical experience/date of surgery were correlated with blood loss when controlling for surgical method. There was no association between any of these variables and blood loss (P > 0.05).
4. Discussion Our results demonstrate that microdebrider tonsillectomy (with or without adenoidectomy) is associated with greater intraoperative blood loss than electrocautery tonsillectomy in children. Four prospective studies [8,9,11,15] and one retrospective study [10] found similar results to ours. Although we did not record blood lost during adenoidectomy versus tonsillectomy portions of an adenotonsillectomy, we were able to mathematically determine the amount of blood lost from each of the composite procedures. While Koltai et al. [5,6] found no significant difference between microdebrider and electrocautery blood loss, they noted that microdebrider bleeding had the potential to obscure tissue specificity and thereby risk injury to the pharyngeal musculature. The operating surgeon in Bitar’s study [9] as well as in our study also noted poor tissue visibility due to bleeding while performing the microdebrider tonsillectomy. It remains imperative to maintain a proper view of the operative field throughout the surgery. Traditional adenoid curette has been shown to produce more blood loss than suction electrocautery [16] and it may or may not produce more blood loss than microdebrider [17,18]. Our results show that adenoid curette and microdebrider are each associated with more blood loss than suction electrocautery. Like Rodriguez et al. [18], we found no difference between curette and microdebrider. Significant learning curves have been noted with the microdebrider [9,10]. While it was a new technique for our surgeon, the linear regression model showed that microdebrider tonsillectomy blood loss did not statistically change over our 9 month study period. We found that a higher proportion of adenotonsillectomy patients (18%) versus the group as a whole (12%) lost greater than 5% of calculated circulating blood volume. This is due to the additive loss of the tonsils and adenoids. While 5% is a relatively low blood volume that can be replaced easily with crystalloid intravenous infusion, ‘‘5%’’ can serve as a marker for progression toward higher losses. Estimated blood volume for children is 70 ml/kg [14]. Thus only when blood loss approaches 28 ml/kg (40%) does an intervention such as a blood transfusion need to be considered. Because a small percentage of patients could have a postoperative hemorrhage, it would be prudent to keep losses well below 28 ml/kg. Therefore, one may consider the 1.2 ml/kg extra blood loss associated with the microdebrider to be irrelevant.
Difference (ml/kg)
P value
95% CI
(curette more) (microdebrider more) (curette more) (microdebrider more)
0.99 0.03 0.0001 0.04 0.002 0.67
1.8, 0.1, 0.7, 0.0, 0.5, 0.5,
0 1.2 1.2 (microdebrider more)
0.99 0.0007 0.0002
0.6, 0.7 0.4, 1.9 0.5, 1.8
1.3 2.4 2.6 3.0 3.2 1.2
It is essential to consider the risk of postoperative hemorrhage. Large retrospective comparative studies have shown that microdebrider postoperative hemorrhage rates are significantly lower at 0.4–1.1% versus electrocautery rates of 1.9–6.8% [19– 21]. So while the microdebrider is associated with increased blood loss, one could argue for its use because of its lower postoperative hemorrhage risk. Furthermore, most studies show that microdebrider is superior to electrocautery for postoperative pain, length of analgesic use, and return to normal activity and diet [5–11]. Our data are strong in that we had only one operating surgeon, which allowed us to control for surgical technique without having to consider inter-surgeon variability. We also adjusted for the tonsil and adenoid volumes that were suctioned into the blood collection traps and would have artificially raised the measured blood loss. The review of our data was not designed as a prospective interventional study which means the surgical techniques were not randomized. We therefore cannot assume that the microdebrider and electrocautery groups were identical. The surgeon, surgical technicians, and statistical analyst were not blinded to the interventions and thus bias may exist. In conclusion, our suspicion that microdebrider tonsillectomies result in more intraoperative blood loss than electrocautery tonsillectomies was confirmed. By the time the statistical analysis was performed, the surgeon had already rejected the microdebrider for tonsillectomy (but had continued to use it for adenoidectomy). Notwithstanding, the quantity of increased blood loss was not hemodynamically significant. Despite the numeric insight, the surgeon did not return to using the microdebrider since the increased bleeding decreased visibility in the operative field. The surgeon still uses the microdebrider for adenoidectomies where the blood loss is similar to the adenoid curette. Authorship All authors have read, approved, and made significant contributions toward the article. Data access and responsibility Farrel J. Buchinsky had full access to all data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Conflict of interest None (for all authors). Poster presentation This paper was presented as a poster at the AAO-HNSF Annual Meeting and Oto Expo in September, 2011:Stansifer KJ,
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Szramowski MG, Barazsu L, Post JC, Buchinsky FJ. Adenotonsillectomy bleeding: microdebrider vs. electrocautery. American Academy of Otolaryngology – Head and Neck Surgery Foundation Annual Meeting and Oto Expo, San Francisco, CA, USA, September 11–14, 2011. References [1] T.A. Weimert, J.W. Babyak, H.J. Richter, Electrodissection tonsillectomy, Arch. Otolaryngol. Head Neck Surg. 116 (2) (1990) 186–188. [2] B.K. Erickson, D.R. Larson, J.L. St Sauver, R.A. Meverden, L.J. Orvidas, Changes in incidence and indications of tonsillectomy and adenotonsillectomy, 1970–2005, Otolaryngol. Head Neck Surg. 140 (6) (2009) 894–901. [3] D.H. Darrow, Surgery for pediatric sleep apnea, Otolaryngol. Clin. North Am. 40 (4) (2007) 855–875. [4] P.J. Koltai, A.S. Kalathia, P. Stanislaw, H.A. Heras, Power-assisted adenoidectomy, Arch. Otolaryngol. Head Neck Surg. 123 (7) (1997) 685–688. [5] P.J. Koltai, C.A. Solares, E.J. Mascha, M. Xu, Intracapsular partial tonsillectomy for tonsillar hypertrophy in children, Laryngoscope 112 (8 (Pt 2 (Suppl. 100))) (2002) 17–19. [6] P.J. Koltai, C.A. Solares, J.A. Koempel, K. Hirose, T.I. Abelson, P.R. Krakovitz, et al., Intracapsular tonsillar reduction (partial tonsillectomy): reviving a historical procedure for obstructive sleep disordered breathing in children, Otolaryngol. Head Neck Surg. 129 (5) (2003) 532–538. [7] M.T. Lister, M.J. Cunningham, B. Benjamin, M. Williams, A. Tirrell, D.A. Schaumberg, et al., Microdebrider tonsillectomy vs. electrosurgical tonsillectomy: a randomized, double-blind, paired control study of postoperative pain, Arch. Otolaryngol. Head Neck Surg. 132 (6) (2006) 599–604. [8] C.S. Derkay, D.H. Darrow, C. Welch, J.T. Sinacori, Post-tonsillectomy morbidity and quality of life in pediatric patients with obstructive tonsils and adenoid: microdebrider vs. electrocautery, Otolaryngol. Head Neck Surg. 134 (1) (2006) 114–120. [9] M.A. Bitar, C. Rameh, Microdebrider-assisted partial tonsillectomy: short- and long-term outcomes, Eur. Arch. Otorhinolaryngol. 265 (4) (2008) 459–463.
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