Histologic assessment of thermal injury to tonsillectomy specimens: a comparison of electrocautery, coblation, harmonic scalpel, and tonsillotome

Bigger Is Not Always Better: Effects of Electrocautery Setting on Tissue Injury in a Porcine Model

Introduction

Electrosurgery for dissection and hemostasis remains one of the foundational tools for the field of surgery as a whole. Monopolar cautery remains the most utilized modality for achieving the aforementioned goals. Given the prolonged history and pre-modern development of "Bovie" cautery, there remains a paucity of data regarding appropriate settings and intensity for various tissue types, procedures, or locales. As a result, utilized settings depend on precedent and personal preference. We aimed to determine the amount of secondary soft tissue injury by volume and depth beyond the electrocautery pen tip in the skin and subcutaneous tissue as well as skeletal muscle. 

Methods

Porcine samples were used for experimental testing using two testing types: 1) skin and subcutaneous tissue and 2) Skeletal muscle. Sample sizes were standardized at 1 cm3 cubes. For skin samples, tissue injury was created with either a scalpel or electrocautery pen on cut setting, and tested at intensities from 10 to 150 in increments of 10. Skeletal muscle samples were similarly tested using the electrocautery pen only in either a cut or coagulation setting. Samples were tested at incremental intensities from 10 to 120 for both settings. Electrocautery was tested for a period of five seconds with a continuous current. All samples were placed in formalin and underwent histologic staining with hematoxylin and eosin staining to be assessed for the extent of tissue injury in terms of depth, radius, and volume. The measurements were recorded in millimeters.

Results

For skin incision, there was a positive and significant correlation with respect to the radius (R=.73, p=0.006). When considering intensity with an interval of 10-70 there was a positive and significant correlation with respect to the radius, depth, and volume. The cold knife incision had no notable soft tissue injury beyond the depth of the incision. Regarding skeletal muscle, again, a significant and positive correlation between increasing monopolar settings was noted for both the coagulation and cut functions (R=.84, p=.0005; R=0.84, p=0.0006). A positive correlation was found between increasing cut intensity and volume of soft tissue injury (R=0.73, p=.008); this was not reflected in the coagulation setting. When limited to an intensity range of 10-60, a significant relationship was noted for depth, radius and volume (R=.95, p= <0.001; R=0.98, p= <.001; R=.92, p=.001).

Conclusion

In all samples, apart from the cold knife skin incision, additional soft tissue injury beyond the tip of the electrocautery pen was noted. Given our findings, recommendations include using the lowest setting required for the purposes of the given surgical case as well as minimizing electrocautery use for skin incisions given its association with a larger volume of tissue injury in comparison with a scalpel. Additionally, electrocautery should be used with care in, and around neurovascular structures as soft tissue injury did occur several millimeters beyond the tip of the electrocautery pen. Further study is needed to see if these patterns are similar in living animals as well as human tissue and whether they bear any clinical impact on surgical wound healing or other surgical complications.

Comparison of outcomes between thermal welding forceps, controlled ablation and monopolar electrosurgery for tonsillectomy in children

OBJECTIVE

To compare recovery from tonsillectomy using thermal welding forceps (TWF), controlled ablation (CA), and monopolar electrosurgery (MES) in children.

METHODS

This was a prospective single blinded observational study using data from electronic medical record (EMR) and caregiver completed patient diary, conducted at a community-based children's hospital within an academic program with tonsillectomy performed by attending surgeons. Children aged 3-17 years undergoing tonsillectomy or adenotonsillectomy by TWF, CA, or MES over a 4-year period were included. Demographics, intraoperative time for tonsillectomy, blood loss, patient diary documentation of pain levels, analgesic doses, diet type and events per day were recorded. In addition, EMR documentation of morbidity events (bleeding, visits for bleeding, return to operating room [OR], total visits or admissions, poor oral intake or dehydration) were noted. To assess for differences in baseline characteristics, we utilized analysis of variance and Pearson's χ² test. To determine primary outcomes, we used a multilevel mixed-effect linear regression model.

RESULTS

A total of 369 children were enrolled, and 346 who met inclusion criteria underwent tonsillectomy. The children were categorized by the instrument used by the surgeons: CA 32.4% (n = 112), MES 36.7% (n = 127), and TWF 30.9% (n = 107). Mean age overall was 6.8 ± 3.2 years, with 57.4% female and 42.6% male. Diary return rate was 52.3% (n = 181) overall, with CA at 48.2% (n = 54), MES at 44.8% (n = 57), and TWF at 65.4% (n = 70). Average pain on the day of surgery was different between instruments with CA having the lowest level of 2.0 compared to 2.7 for TWF and MES (p = 0.001). Maximum pain level for day of surgery were lowest for CA at 2.7 compared to 3.4 for MES and 3.5 for TWF (p = 0.003). Pain levels were lowest for TWF after postoperative day (POD) 6. Overall rate of bleeding was 9.3%, with 2.6% return to surgery for control of bleeding. TWF had the lowest rate of bleeds (4.7% versus CA 11.6% and MES 11.0%), return to surgery (0.0% versus CA 2.7% and MES 4.7%), the earliest and final return to regular diet at POD 5.8 and 8.1, respectively without reaching statistical significance.

CONCLUSION

CA had significantly lowest early pain levels on day 0-1 and trended lowest up to POD 6, after which TWF was lowest but did not reach statistical significance. TWF had the earliest return to regular diet. Children undergoing CA and MES are more likely to have a postoperative bleed and a return to the OR than TWF suggesting improved ability to seal vessels with the latter instrument. Further study with a larger sample is needed.

Bipolar loop device versus bipolar diathermy for tonsillectomy: A pilot randomized controlled trial

OBJECTIVE

Tonsillectomy is one of the most common surgeries performed in the pediatric population. Although different forms of instruments and various methods are used to perform tonsillectomy, none of them is still recognized as the best global technique. This study aimed to compare the outcomes of the new Bipolar Loop tonsillectomy versus bipolar diathermy technique.

METHODS

This study is a pilot randomized clinical trial and was conducted on 40 pediatric patients who were the candidate of tonsillectomy. Patients were divided into two groups of Bipolar Loop or bipolar diathermy. Operation time, intraoperative bleeding, tonsillar fossa wound, postoperative complications, and duration of return to normal diet were evaluated in the current study.

RESULTS

In both of the Bipolar Loop and bipolar diathermy groups, no significant difference was found in terms of sex, age, and weight. The average amount of the operative time, intra-operative blood loss, and postoperative pain loss were significantly less in the Bipolar Loop group (P < .001). In addition, the tonsillar fossa wound healing scores were significantly better (on the 14th day, P = 0.009). However, there was no significant difference between the two groups in terms of postoperative bleeding, duration of return to a normal diet, and postoperative symptoms of fever, otalgia, or voice change between the groups.

CONCLUSION

The study showed that blood loss and postoperative pain through day 7 were significantly less in the Bipolar Loop group. Tonsillectomy with Bipolar Loop can be recommended as one of the methods for tonsillectomy, especially in pediatric patients.

Cost benefit of coblation versus electrocautery adenotonsillectomy for pediatric patients

INTRODUCTION

Coblation and electrocautery are two common techniques used for adenotonsillectomy (T&A). Numerous studies have assessed surgical outcomes of coblation versus electrocautery and overall, postoperative complications are similar with the exception of a decrease in patient reported postoperative pain for coblation. Instrumentation required for coblation is significantly more expensive than that required for electrocautery. With minimal outcome differences, justification for the additional instrumentation costs is difficult. We performed this study to assess if there is a difference between operative & postoperative costs of electrocautery and coblation.

METHODS

300 patient medical records were reviewed from 2015 to 2017 with equal numbers of electrocautery and coblation surgeries. Outcome measures included finance information, duration and cost of OR and Phase I and Phase II post-anesthesia care unit (PACU), in-hospital pharmacy costs, and postoperative complications. Logistic regression was used for analysis.

RESULTS

The median patient age for each surgical technique was 6 years old. Electrocautery resulted in more time in the OR compared to coblation, (OR:1.11,95%CI:1.07-1.15, p < .001), with greater associated costs, p < .001. Electrocautery patients were under anesthesia longer and had a longer surgical duration, p < .001. These same patients had longer duration in Phase II PACU, p = .028, and were given pain medications an increased number of times, p < .001. Total costs including operative expense, physician charges, OR and anesthesia times, pharmacy, and instrument were significantly higher for electrocautery patients, p = .003. There were no differences in ED visits, post-tonsillectomy bleed, or additional surgery between techniques, p > .05.

CONCLUSION

T&A electrocautery technique was found to have increased overall indirect costs. Costs of instrumentation in addition to increased operative time, use of analgesics and post-operative care contribute to costs associated with electrocautery and coblation should be used when assessing surgical costs.

Plasma-Mediated Bipolar Radiofrequency Ablation of Overlong Soft Palate in the Dog: A Pilot Study

The objective of this study was to compare the clinical, biological, macroscopic, and histologic outcomes after resection of the soft palate by plasma-mediated bipolar radiofrequency ablation (PBRA) or traditional incisional techniques (incisional soft palate resection [INC]) in dogs. Ten dogs were divided in two groups. In the INC group, the soft palate was incised with scissors and the wound was sutured in a continuous pattern. In the PBRA group, a wand was used to ablate the desired portion of the soft palate, without suture. Clinical, biological, macroscopic, and histologic assessments were scheduled over 14 days. The duration of surgery was significantly shorter for the PBRA group. The C-reactive protein concentrations were significantly higher in the PBRA group at 6 hr and on day 3 (P < .05) but with values very close to the baseline. C-reactive protein concentrations were maximal, but with low values (<25 mg/L), at day 1 for both techniques. The irregularity scores for the soft palate caudal border on days 1, 3, and 14 were significantly higher in the INC group than in the PBRA group (P < .05). The main histopathologic changes were the presence of superficial granulomas and a significantly greater depth of tissue damage in the INC group (2.5 ± 0.3 mm) compared with the PBRA group (1.5 ± 0.1 mm; P < .05). PBRA compared favorably with the traditional technique in terms of ease, duration of surgery, and depth of tissue damage. Future studies are warranted to validate its effectiveness for treating brachycephalic airway obstruction syndrome in dogs.

Post-tonsillectomy pain after using bipolar diathermy scissors or the harmonic scalpel: a randomised blinded study

Objective

To compare the postoperative pain following bipolar diathermy scissors tonsillectomy (higher temperature dissection) with harmonic scalpel tonsillectomy (lower temperature dissection).

Methods

Sixty patients aged 7–40 years planned for tonsillectomy with no other concurrent surgery were randomised to either bipolar diathermy scissors or harmonic scalpel as surgical technique. Blinded to the surgical technique, the patients recorded their pain scores (VAS, 0–10) at awakening and the worst pain level of the day in the postoperative period. All intake of pain medication was also recorded.

Results

No statistically significant differences were found between the two groups regarding postoperative pain levels or consumption of pain medication.

Conclusion

Usage of the harmonic scalpel does not render less postoperative pain following tonsillectomy when compared with usage of the bipolar diathermy scissors.

Histomorphological features of resected bladder tumors: Do energy source makes any difference

Context:

The recent advent of bipolar energy in bladder tumor resection has raised many questions regarding density of current and its effect on histopathology of the resected transurethral resection of bladder tumor (TURBT) chips.

Aims:

The aim of this study is to evaluate the histomorphological features in resected bladder tumors comparing bipolar versus conventional (monopolar) energy.

Settings and Design:

Inclusion criteria were patients with primary presentation of carcinoma urinary bladder undergoing TURBT. The patients with prior resections were excluded as these could jeopardize the results of cautery artifacts.

Materials and Methods:

From February 2010 to December 2011, 61 patients with primary carcinoma bladder and meeting our inclusion criteria were compared. Group 1 (n = 31) underwent bipolar-TURBT (B-TURBT) and Group 2 (n = 30) monopolar-TURBT (M-TURBT). Two pathologists, who were blinded to the form of electrocautery used, examined the resected tissue. The degree of cautery artifact in each specimen was recorded. The severity of the cautery artifact was graded as absent, mild, moderate, or severe. The mean age, tumor size, and resection time were recorded in both groups.

Statistical Analysis Used:

Data were analyzed using SPSS 16. Data were compared in between groups using paired t-test and Pearson's Chi-square test. The significance level was set at 0.05.

Results:

The mean age, tumor size, and resection time were similar in between the two groups. The pathologists had no obscurity in reaching a correct diagnosis in all cases. The cautery artifacts were graded as absent in 10 (32.2%) and 8 (26.67%), mild in 12 (38.7%) and 11 (36.67%), moderate in 5 (16.1%) and 7 (23.33%) and severe in 4 (12.9%) and 5 (16.66%) cases, respectively in Group 1 and 2. There was no statistically significant histomorphogical dissimilarity between specimens according to the type of cautery used.

Conclusions:

Bladder tissue obtained from B-TURBT is of equivalent histomorphological feature as that of standard M-TURBT.

Laparoscopic colpotomy using monopolar electrocautery: does power really matter?

OBJECTIVE

The purpose of this study was to assess the extent and rate of vaginal tissue injury associated with the utilization of various monopolar electrosurgical power settings when laparoscopically transecting vaginal tissue.

METHODS

This is an Institutional Animal Care and Use Committee-approved prospective, paired, single-blinded study. Externalized porcine vagina was transected using monopolar energy at 30, 50, and 80 W in the cut mode with laparoscopic Endo Shears. The slides were prepared and stained with both hematoxylin-eosin and Masson trichrome and were examined by board-certified veterinary pathologists blinded to the study.

RESULTS

There were 18 swine; each animal was tested on all 3 power settings (n = 54). Tissue injury was measured to a mean (SD) of 767 (519) μm at 30 W, 690 (600) μm at 50 W, and 556 (470) μm at 80 W. When comparing the monopolar settings, the results were as follows: 30 versus 50 W (P = 0.33), 30 versus 80 W (P = 0.067), and 50 versus 80 W (P = 0.17). The mean (SD) time for complete transection was measured at each power setting (n = 18), with 35.8 (5.4) seconds for 30 W, 13.5 (5.5) seconds for 50 W, and 8.4 (5.1) seconds for 80 W (P < 0.001). There was a statistically significant difference in the mean (SD) rates of injury, with 20.8 (8.8) μm/s at 30 W, 39.8 (11.8) μm/s at 50 W, and 50.1 (19.2) μm/s at 80 W (P = 0.01).

CONCLUSIONS

Using various power settings of monopolar energy may not make a significant difference in swine vaginal tissue damage at the time of colpotomy. However, there was a significant difference in the times and rates at which tissue was transected when using higher powers. We recommend using the 50- or 80-W setting, as this will likely decrease surgical times without altering vaginal tissue damage.

Intraoperative ice pack application for uvulopalatoplasty pain reduction: a randomized controlled trial

OBJECTIVES/HYPOTHESIS

Pain after uvulopalatoplasty continues to cause patients significant morbidity, especially from the tonsillectomy portion. The literature describes multiple techniques to reduce post-tonsillectomy pain, none being definitive. The purpose of this study was to evaluate the effect of intraoperative ice pack application on post-uvulopalatoplasty pain.

STUDY DESIGN

Single-blinded, randomized controlled trial.

METHODS

After inclusion and exclusion criteria were met, patients were enrolled and randomized, and subsequently underwent standard electrocautery uvulopalatoplasty. Packs were placed into the tonsillar fossae immediately following tonsil removal and into the palate after the palatoplasty. Patients then completed a questionnaire that evaluated their experience for 10 days following surgery. The primary outcome was pain rated on a visual analog scale. Return to work and return to normal diet were also assessed. T test and Mann-Whitney statistical analyses, as well as routine descriptive statistics, were conducted.

RESULTS

Eighteen subjects were recruited. Patients that received intraoperative cold packs experienced a statistically significant change in VAS average pain [3.4 ± 1.1 cm (p = 0.00001)] when compared with patients receiving room temperature packs. No difference in return to work (p = 0.16) and return to normal diet (p = 0.12) was identified.

CONCLUSIONS

Intraoperative ice pack administration results in significantly reduced pain following electrocautery uvulopalatoplasty.

Ultrasonic scalpel causes greater depth of soft tissue necrosis compared to monopolar electrocautery at standard power level settings in a pig model

Background

Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are common tools for soft tissue dissection. However, morphological data on the related tissue alteration are discordant. We developed an automatic device for standardized sample excision and compared quality and depth of morphological changes caused by UC and ME in a pig model.

Methods

100 tissue samples (5 × 3 cm) of the abdominal wall were excised in 16 pigs. Excisions were randomly performed manually or by using the self-constructed automatic device at standard power levels (60 W cutting in ME, level 5 in UC) for abdominal surgery. Quality of tissue alteration and depth of coagulation necrosis were examined histopathologically. Device (UC vs. ME) and mode (manually vs. automatic) effects were studied by two-way analysis of variance at a significance level of 5%.

Results

At the investigated power level settings UC and ME induced qualitatively similar coagulation necroses. Mean depth of necrosis was 450.4 ± 457.8 μm for manual UC and 553.5 ± 326.9 μm for automatic UC versus 149.0 ± 74.3 μm for manual ME and 257.6 ± 119.4 μm for automatic ME. Coagulation necrosis was significantly deeper (p < 0.01) when UC was used compared to ME. The mode of excision (manual versus automatic) did not influence the depth of necrosis (p = 0.85). There was no significant interaction between dissection tool and mode of excision (p = 0.93).

Conclusions

Thermal injury caused by UC and ME results in qualitatively similar coagulation necrosis. The depth of necrosis is significantly greater in UC compared to ME at investigated standard power levels.