A Single-Center, Single-Surgeon Retrospective Comparative Study of BiZact Tonsillectomy and Monopolar Cautery Tonsillectomy
단일 기관, 단일 술자에 의한 BiZact 편도절제술과 단극성 전기소작 편도절제술의 후향적 비교 연구
Article information
Abstract
Background and Objectives
To compare the perioperative and postoperative outcomes of tonsillectomy performed using BiZact and the monopolar cautery.
Subjects and Method
This retrospective study, conducted at a single-institution by a single-surgeon, included patients of all ages who underwent tonsillectomy between January 2023 and December 2025. Patients were grouped according to the device used, BiZact or the monopolar cautery. The age-stratified subgroup analyses were performed for pediatric (≤18 years) and adult (≥19 years) patients. Operative time, postoperative bleeding, and pain-related outcomes were reviewed from medical records. Continuous variables were compared using the Mann-Whitney U test, and categorical variables using the chi-square test or Fisher’s exact test.
Results
The operative time was shorter in the BiZact group in both pediatric patients (25.3±7.3 min vs. 34.8±16.7 min; p<0.001) and adult patients (19.8±7.0 min vs. 28.1±11.9 min; p=0.001). In the pediatric subgroup, the use of in-hospital pro re nata (PRN) analgesics (16.2% vs. 26.8%; p=0.048) and additional analgesic prescriptions at the first postoperative visit (21.5% vs. 40.9%; p=0.001) were less frequent in the BiZact group. In the adult subgroup, additional analgesic prescriptions at the first postoperative visit were also less frequent in the BiZact group (47.5% vs. 85.7%; p<0.001), whereas the use of in-hospital PRN analgesics did not differ significantly. Postoperative bleeding outcomes were similar between the two groups in both age subgroups.
Conclusion
The BiZact tonsillectomy was associated with shorter operative time in both pediatric and adult patients and with reduced postoperative analgesic requirement, particularly in the pediatric patients, while postoperative bleeding outcomes were similar between groups. These findings support BiZact as a useful alternative device for tonsillectomy.
Introduction
Tonsillectomy is a commonly performed procedure in both pediatric and adult populations. According to the 2023 Korean National Health Insurance Service statistical yearbook, which covers 34 major procedures, tonsillectomy ranked 17th overall, with a total 25043 procedures performed on 24689 patients nationwide. Tonsillectomy was the most frequently performed major procedure in children aged 9 years or younger and was among the five most common procedures in patients in their 20s [1]. Although indications differ somewhat with age, the principal reasons for tonsillectomy are recurrent tonsillitis or tonsilloliths, and obstructive sleep-disordered breathing, including obstructive sleep apnea related to tonsillar hypertrophy. Sleep-disordered breathing is a leading indication in children, whereas chronic or recurrent infections remain major indications in adults [2,3].
Although tonsillectomy is generally considered a safe and well-established procedure in pediatric and adult populations, postoperative complications remain clinically important. In particular, postoperative pain and post-tonsillectomy hemorrhage continue to be the major sources of morbidity after surgery [3]. Despite the relatively short operative time, tonsillectomy may still be associated with delayed recovery, including difficulty with oral ingestion and delayed return to a normal diet. Therefore, reducing postoperative pain and hemorrhage remains an important goal in optimizing tonsillectomy outcomes [4].
Various techniques and energy devices have been introduced to improve tonsillectomy outcomes, particularly postoperative pain and hemorrhage; however, the optimal surgical method remains unclear. Cold-knife tonsillectomy is a conventional extracapsular technique with a separate hemostasis step, whereas monopolar and bipolar cautery permit dissection with electrosurgical hemostasis. LigaSure represents an advanced bipolar vessel-sealing device with feedback-controlled energy delivery. Powered intracapsular tonsillectomy and adenoidectomy is a microdebrider-based intracapsular technique intended to preserve the tonsillar capsule and promote faster recovery [5,6]. Of these techniques, monopolar cautery remains widely used because of the surgeon’s familiarity with the approach and its ability to provide efficient dissection with hemostasis [7]. In addition, monopolar electrocautery may offer lower instrument-related costs than newer disposable systems such as coblation or microdebrider-based techniques [8].
BiZact (Medtronic) is a bipolar tonsillectomy device that continuously measures tissue impedance and adjusts energy delivery in real time to achieve sealing and division of tissue simultaneously. It has been introduced as an alternative device for tonsillectomy procedures [9-11]. The instrument has a 12-cm shaft and a curved jaw designed to conform to the tonsillar bed and is indicated for sealing vessels up to 3 mm in diameter. Using controlled bipolar energy and minimizing lateral thermal spread, the device has been introduced as a surgical option designed to improve procedural efficiency and limit collateral thermal injury [12].
The aim of this study was to compare perioperative and postoperative outcomes between BiZact tonsillectomy and conventional monopolar cautery tonsillectomy. In particular, we evaluated postoperative hemorrhage- and pain-related outcomes, which were assessed by the need for additional analgesic requirements during hospitalization and/or up to the first postoperative outpatient visit. We also compared the operative time between the two techniques.
Subjects and Methods
Study design and patient selection
This was a single-institution, single-surgeon retrospective chart review conducted at a tertiary referral hospital. All the procedures were performed by a single otolaryngologist with 20 years of surgical experience. We retrospectively reviewed the electronic medical records of consecutive pediatric and adult patients who underwent tonsillectomy or adenotonsillectomy under general anesthesia between January 1, 2023, and December 31, 2025. The surgical device used for tonsillectomy was determined according to the operative period based on the surgeon’s routine practice. Patients who underwent surgery from January 1, 2023, to October 31, 2024, were treated using monopolar cautery, whereas those who underwent surgery from November 1, 2024, to December 31, 2025, were treated using BiZact. Thus, the choice of device was not determined individually for each patient. Perioperative management, including the inpatient analgesic regimen, discharge criteria, and scheduled postoperative follow-up, remained unchanged throughout the study period. In Korea, tonsillectomy is covered under the diagnosis-related group-based reimbursement system, under which inpatient care is typically delivered according to a relatively standardized clinical pathway. In addition, age-stratified subgroup analyses were performed by categorizing patients into pediatric (≤18 years) and adult (≥19 years) groups [13]. The surgeon had prior experience with BiZact before the study period and was already familiar with and proficient in its use when the operations were performed. When adenoidectomy was indicated, it was performed using a curettage technique throughout the study period. This study was conducted in accordance with the ethical principles of the Declaration of Helsinki and was approved by the Institutional Review Board of Kangbuk Samsung Hospital (Approval No. 2026-02-010).
Inclusion and exclusion criteria
The inclusion criteria were patients of all ages indicated for tonsillectomy under general anesthesia at our institution during the study period, with or without adenoidectomy. Patients were excluded if they refused authorization to use their medical information for research; underwent unilateral tonsillectomy for pathologic examination; or underwent concomitant surgical procedures other than adenoidectomy, such as vocal cord polyp surgery, unilateral or bilateral myringotomy, or ventilation tube insertion for middle ear effusion.
Perioperative management and follow-up
Perioperative management, including the analgesic regimen, admission and discharge criteria, and follow-up schedule, was standardized in both groups. The patients were routinely admitted the day before surgery, underwent tonsillectomy under general anesthesia, and were discharged the following day. During hospitalization, pain was controlled with intravenous weight-based acetaminophen (15 mg/kg) administered every 8 hours. If pain was insufficiently controlled, additional intravenous weight-based ibuprofen (10 mg/kg) was administered as needed (pro re nata, PRN). At discharge, the patients were prescribed oral weight-based acetaminophen every 8 hours for 7 days. Routine outpatient follow-up was scheduled 1 week after surgery. Patients and/or their caregivers were instructed to visit the emergency department if any postoperative bleeding occurred before the scheduled follow-up visit.
Data collection
Demographic, perioperative, and postoperative data were extracted from the electronic medical records through a retrospective chart review. The collected variables included age, sex, type of surgery (tonsillectomy alone or adenotonsillectomy), tonsil grade, chief complaint, operative time, postoperative bleeding episodes, and pain-related outcomes. Tonsil grade was classified from 1 to 4 based on preoperative endoscopic images. The chief complaints leading to surgery were categorized as frequent tonsillitis, tonsilloliths, or snoring. Patients were grouped according to the surgical device used, namely BiZact or monopolar cautery. Operative time was determined using the electronically recorded start and end times entered into the operating room computer system by the anesthesia team and was defined as the interval from the start of surgical preparation after induction of general anesthesia to the point at which patient awakening was initiated after completion of surgery. Postoperative bleeding episodes were classified into three categories: bleeding during hospitalization, bleeding-related emergency room visits within 1 week after discharge, and evidence of bleeding noted on examination of the operative site at the first outpatient visit after discharge. Evidence of bleeding noted at the first outpatient visit was defined as the presence of a blood clot, with or without fresh bloody oozing, on the tonsillar fossa during examination. Postoperative pain was evaluated using two pain-related surrogate measures: the need for as-needed (PRN) analgesic administration during hospitalization, reflecting early postoperative pain, and the need for an additional analgesic prescription at the outpatient visit 1 week after surgery, reflecting persistent or delayed postoperative pain [14-16]. Additional analgesics at the 1-week outpatient visit were prescribed when patients or caregivers reported persistent or insufficiently controlled pain after discharge.
Statistical analysis
All statistical analyses were performed using Windows SPSS v.24.0. (IBM Corp.). Continuous variables were summarized as mean±standard deviation and median with interquartile range (IQR), whereas categorical variables were presented as numbers and percentages. All continuous variables were compared between groups using the Mann-Whitney U test. Categorical variables were compared using Pearson’s chi-square test or Fisher’s exact test, as appropriate. Because one patient in the BiZact group was lost to follow-up before the 1-week outpatient visit, the outpatient outcomes were analyzed on an available-case basis. All statistical tests were two-sided, and a p-value <0.05 was considered statistically significant.
Results
During the study period, 373 patients were identified based on the inclusion criteria. After excluding two patients who declined authorization for the use of medical information for research, five who underwent unilateral tonsillectomy for pathologic examination, two who underwent concomitant vocal cord polyp surgery, and 24 who underwent concomitant unilateral or bilateral myringotomy or ventilation tube insertion for middle ear effusion, 340 patients were included in the final analysis. Of these, 171 patients were assigned to the BiZact group and 169 to the monopolar cautery group. The BiZact group comprised 130 pediatric patients and 41 adult patients, whereas the monopolar cautery group comprised 127 pediatric patients and 42 adult patients. One adult patient in the BiZact group was lost to follow-up before the 1-week postoperative visit and had no record of a postoperative visit to the emergency department or any outpatient clinic within our institution (Fig. 1).
Flowchart of patient selection, exclusion, and final group allocation in the study cohort.
The baseline characteristics of the pediatric and adult subgroups are summarized in Tables 1 and 2, respectively. In the pediatric subgroup, there were no significant differences between the BiZact and monopolar cautery groups in sex distribution (p=0.685), age (p=0.240), tonsil grade (p=0.939), chief complaint (p=0.853), or type of operation (p=0.352). The median age was 8 years (IQR, 6-10; range, 4-18) in the BiZact group and 9 years (IQR, 6-10; range, 4-18) in the monopolar cautery group. In the adult subgroup, there were no significant differences between the two groups in sex distribution (p=0.133), age (p=0.460), tonsil grade (p=0.169), or chief complaint (p=0.813). And all adult patients in both groups underwent tonsillectomy alone. The median age was 32 years (IQR, 28-39; range, 19-69) in the BiZact group and 31 years (IQR, 26-38; range, 19-60) in the monopolar cautery group.
Baseline characteristics of the pediatric subgroup
Baseline characteristics of the adult subgroup
Perioperative and postoperative outcomes in the pediatric and adult subgroups are summarized in Tables 3 and 4, respectively. In the pediatric subgroup, operative time was significantly shorter in the BiZact group than in the monopolar cautery group (median [IQR], 25 [20-30] min vs. 30 [20-45] min; p<0.001). Pain-related outcomes also differed between the two groups. Additional PRN analgesics during hospitalization were required less frequently in the BiZact group than in the monopolar cautery group (21/130, 16.2% vs. 34/127, 26.8%; p=0.048). At the first postoperative outpatient visit, additional analgesic prescription was also less common in the BiZact group (28/130, 21.5% vs. 52/127, 40.9%; p=0.001) (Fig. 2). In the adult subgroup, operative time was also significantly shorter in the BiZact group than in the monopolar cautery group (median [IQR], 20 [15-25] min vs. 25 [20-38.8] min; p=0.001). Regarding pain-related outcomes, additional analgesic prescription at the first postoperative outpatient visit was less frequent in the BiZact group than in the monopolar cautery group (19/40, 47.5% vs. 36/42, 85.7%; p< 0.001), whereas in-hospital PRN analgesic use did not differ significantly between the two groups (9/41, 22.0% vs. 13/42, 31.0%; p=0.457) (Fig. 3).
Perioperative and postoperative outcomes of the pediatric subgroup
Perioperative and postoperative outcomes of the adult subgroup
Pain-related postoperative outcomes of the pediatric subgroup between the monopolar cautery and BiZact groups. PRN, pro re nata.
Pain-related postoperative outcomes of the adult subgroup between the monopolar cautery and BiZact groups. PRN, pro re nata.
Bleeding-related outcomes were comparable between the two groups in both age subgroups. In the pediatric subgroup, postoperative bleeding was not observed during hospitalization in either group. After discharge, bleeding-related emergency room visits occurred in 1 patient (0.8%) in the BiZact group and 4 patients (3.1%) in the monopolar cautery group, with no significant difference between the groups (p=0.210). In addition, bleeding was noted at the first postoperative outpatient visit in 4 patients (3.1%) in the BiZact group and 3 patients (2.4%) in the monopolar cautery group (p>0.999). Neither reoperation for hemostasis nor hospital readmission was required in either group (Fig. 4). In the adult subgroup, postoperative bleeding was not observed during hospitalization in either group. After discharge, bleeding-related emergency room visits occurred in 2 patients (4.9%) in the BiZact group and 2 patients (4.8%) in the monopolar cautery group, with no significant difference between the groups (p>0.999). Postoperative bleeding was noted at the first outpatient visit in 3 patients (7.5%) in the BiZact group and 4 patients (9.5%) in the monopolar cautery group (p>0.999). In both the pediatric and adult subgroups, the patients who presented with bleeding-related emergency room visits within 1 week after discharge were distinct from those in whom bleeding was noted at the 1-week outpatient visit; thus, the two bleeding-related events were mutually exclusive. Neither reoperation for hemostasis nor hospital readmission was required in either group (Fig. 5). All postoperative bleeding episodes were successfully controlled with office-based cauterization in the outpatient clinic.
Bleeding-related postoperative outcomes of the pediatric subgroup between the monopolar cautery and BiZact groups. ER, emergency room.
Bleeding-related postoperative outcomes of the adult subgroup between the monopolar cautery and BiZact groups. ER, emergency room.
Discussion
In this single-institution, single-surgeon retrospective study, BiZact tonsillectomy was associated with a significantly shorter operative time than monopolar cautery tonsillectomy in both pediatric and adult patients. With regard to pain-related outcomes, age-stratified subgroup analyses showed different patterns between the two age groups. In the pediatric subgroup, BiZact was associated with lower in-hospital PRN analgesic use and a lower rate of additional analgesic prescription at the first postoperative outpatient visit. In the adult subgroup, however, although additional analgesic prescription at the first postoperative outpatient visit was less frequent in the BiZact group, in-hospital PRN analgesic use did not differ significantly between the two groups. Regarding postoperative bleeding outcomes, no significant differences were observed between the two groups in either age subgroup with respect to bleeding-related emergency room visits or bleeding noted at the 1-week outpatient visit. Taken together, these findings suggest that BiZact may improve operative efficiency and may be associated with more favorable postoperative pain-related outcomes, particularly in pediatric patients, without increasing the risk of postoperative hemorrhage [17-19].
The shorter operative time observed in the BiZact group may be attributed to the device’s bipolar sealing and division mechanism, which allows tissue dissection and hemostasis to be performed in a streamlined manner [18]. In contrast, compared with a device that combines tissue sealing and division, monopolar cautery may require more intermittent hemostatic control during tonsil dissection [20]. However, the operative time in the present study was not limited to the time required for tonsillectomy itself because it was determined from the electronically recorded operating room times entered by the anesthesia team. Therefore, the measured operative time may not have fully reflected the pure dissection time of tonsillectomy.
Pain-related outcomes were also more favorable in the BiZact group, particularly in pediatric patients. In the adult subgroup, only additional analgesic prescription at the first postoperative outpatient visit differed significantly between the two groups, whereas in the pediatric subgroup both in-hospital PRN analgesic use and additional analgesic prescription at 1 week after surgery were lower in the BiZact group. One possible explanation is that the controlled bipolar energy delivery of BiZact may have reduced collateral thermal injury to the surrounding tonsillar bed compared with monopolar cautery [12]. Reduced local tissue injury may in turn have contributed to less postoperative pain, thereby facilitating recovery [21]. However, pain in the present study was assessed indirectly using analgesic requirements rather than by a validated pain score, which should be considered when interpreting the results [22]. Furthermore, because the decision to prescribe additional analgesics at the first postoperative outpatient visit was made in a non-blinded clinical setting, this outcome measure may have been influenced, at least in part, by physician judgment [23].
Postoperative bleeding outcomes were comparable between the two groups. No in-hospital bleeding occurred in either group, and no significant differences in bleeding-related emergency room visits after discharge or bleeding were observed at the first outpatient visit. Importantly, all postoperative bleeding episodes were successfully managed with office-based cauterization, and none of the patients required reoperation or readmission. These results indicate that BiZact was not associated with an increased rate of postoperative bleeding compared with conventional monopolar cautery in the present cohort [17]. However, the intraoperative blood loss was not quantitatively assessed in the present study. The inclusion of intraoperative bleeding volume as an additional outcome measure would have provided a more comprehensive evaluation of bleeding-related surgical outcomes [24].
This study has several strengths. Because all procedures were performed by a single experienced surgeon at a single institution, inter-surgeon variability was minimized, allowing for a more consistent comparison between surgical devices [25]. In addition, the surgeon had previous experience with BiZact before the study period, which reduced the potential influence of a long learning curve [10]. Nevertheless, this study has some limitations that should be acknowledged. First, its retrospective design is inherently subject to selection bias and unmeasured confounding factors [26] and because group allocation was determined by operative period rather than random assignment, the present study may have been affected by chronological bias and residual confounding related to temporal changes in clinical practice [27]. Second, operative time in the present study was based on anesthesia record-derived operating room time and therefore may not fully reflect pure tonsil dissection time. Accordingly, the observed difference may have been influenced not only by the surgical device itself but also by other perioperative workflow factors [28]. Third, postoperative pain was not assessed using a standardized pain score but rather by surrogate measures based on analgesic use [22]. Fourth, because BiZact is a single-use disposable device, its additional cost should be considered when interpreting the clinical benefits observed in this study. Whether the reduction in operative time and analgesic requirement is sufficient to justify the added device cost may vary across institutions and was not formally evaluated in the present study [29]. Finally, this was a single-institution study with a relatively limited sample size, which may have reduced its generalizability [30].
In conclusion, in this retrospective comparative study, BiZact tonsillectomy was associated with a shorter operative time than monopolar cautery tonsillectomy in both pediatric and adult patients. Pain-related benefits appeared to be more pronounced in pediatric patients, while postoperative bleeding outcomes remained comparable between the two groups in both age subgroups. These findings support the potential role of BiZact as an alternative surgical device for tonsillectomy, although further prospective validation is required.
Notes
Acknowledgments
None
Author Contribution
Conceptualization: Sang Hyuk Lee. Data curation: Seong Jin Yun, Yong Mo Ahn. Formal analysis: Seong Jin Yun, Yong Mo Ahn. Investigation: Seong Jin Yun, Yong Mo Ahn. Supervision: Sang Hyuk Lee, Gil Joon Lee. Visualization: Seong Jin Yun. Writing—original draft: Seong Jin Yun, Yong Mo Ahn. Writing—review & editing: Sang Hyuk Lee, Gil Joon Lee.