A Comparative Study of Cold Dissection Tonsillectomy and Harmonic Scalpel Tonsillectomy Under Microscope- Our Experience

Abstract

Tonsillectomy is one of the most common proceduresin routine otolaryngology.Given that the pediatric demographic is usually in question, ENT surgeons are resorting to newer modalities that minimize the dreaded complication of intra-operative and post-operative hemorrhage and have shorter operative time. The present study was conducted on patients admitted in ward in the Department of Otorhinolaryngology at SMS Medical College and Hospital, JaipurFrom July 2019 to June 2020 on a sample size of 40 patient diagnosed as adeno-tonsillar hypertrophy of grade 3–4. Each patient underwent tonsillectomy by cold dissection method on one side and by ultrasonic scalpel on other. The present study was conducted on patients admitted in ward in the Department of Otorhinolaryngology at SMS Medical College and Hospital, JaipurFrom July 2019 to June 2020 on a sample size of 40 patient diagnosed as adeno-tonsillar hypertrophy of grade 3–4. Each patient underwent tonsillectomy by cold dissection method on one side and by ultrasonic scalpel on other. In our study Mean operation time, mean blood loss, Analogue score for post-operative pain at 24hrs and 7th postoperative day respectively and Healing of wound on 14th post-operative day were significantly lower in cases of tonsillectomy with harmonic scalpel than cold dissection method tonsillectomy. The novel technique of tonsillectomy harmonic scalpel is proven to be better with regard to lesser operative time, blood loss and lesser post-operative morbidity.

Introduction

Tonsillectomy is one of the most common otorhinolaryngology surgery. Indications for tonsillectomy in children include chronic or recurrent tonsillitis, obstructive symptoms due to hypertrophied tonsils or any other suspicious growths of the tonsils [1].

Until the 1960s, tonsillectomy was performed using the cold dissection method. Gradually with technological advances, other methods such as monopolar and bipolar electro-cautery, micro-debrider, coblation technique,CO₂ laser, bipolar radiofrequency, harmonic scalpel and vessel sealing systems were added to the list, all of which differ in terms of intraoperative bleeding, operation time, pain after surgery, time of starting oral nutrition post-operatively and return to usual activities.

Ideally, tonsillectomy should be quick, painless and associated with minimal blood loss. As it is a matter of concern in pediatric population as incidence is maximum in this age group.In reality, however, the morbidity of tonsillectomy may be significant. Surgeons must consider haemorrhage, apnoea, pain, fever, and poor oral intake as possible effects of the surgery [2].

Differences between surgical methods are described in terms of operative blood loss, operative time, and particularly, postoperative morbidity [3].

Traditional dissection tonsillectomy has remained the gold standard for tonsil removal. It leaves the wound open to heal by secondary intention, thus causes pain and bleeding as two major postoperative complications. Long periods of wound recoveries, taking up to fifteen days, are not so uncommon. This may bear the risk of bleeding from tonsillar bed. Postoperative pain can cause severe limitation in regaining the activities and routine dietary habits [4].

A new technique for tonsillectomy In particular, it preferably should be associated with less postoperative pain, less intraoperative blood loss, allow a more rapid return to normal dietary habits and activity, and carry a lower risk of both reactive and secondary hemorrhage.

In 2000, Ochi et alfirst described the use of the ultrasonic scalpel in human tonsillectomy. The ultrasonic or harmonic scalpel is a hand held device with an ultrasonically activated blade tip that vibrates at 55,500 cycles per second. It cuts by cavitational fragmentation and mechanical disruption of tissues, and coagulates by coaptation. This leads to breakage of tertiary hydrogen bonds to denature protein and form a coagulum [5].

The ultrasonic scalpel has several theoretical advantages over blunt dissection tonsillectomy when electro cautery is used for haemostasis. It should cause less blood loss as the vibrating blade coagulates small vessels as it cuts. This in turn should lead to a decrease in the use of diathermy for haemostasis and with this an associated decrease in operating time. As the ultrasonic scalpel coagulates at temperatures between 50 °C and 100 °C, in comparison with electro cautery, which coagulates at temperatures between 150 °C and 400 °C, there should also be less thermal damage and with this, there may be a decrease in postoperative pain [6].

In this study, we will compare different variables such as tonsillectomy time, intraoperative blood loss, post-operative pain and wound healing with the two methods (harmonic scalpel and cold dissection) under microscopic visualisation to select the best method according to the patient’s condition.

Material and Method.

The present study was conducted on patients admitted in ward in the Department of Otorhinolaryngology at SMS Medical College and Hospital, Jaipur From July 2019 to June 2020 on a sample size of 40 patient diagnosed as adeno-tonsillar hypertrophy of grade 3-4with Cases in which parents /guardian of child give written and informed consent.

Patients of age group 4 to 14 years planned for tonsillectomy/Adeno-tonsillectomy for various indications: recurrent tonsillitis, obstructive sleep apnoea, hypertrophy of tonsils causing difficulty in deglutition, secretory otitis media (glue ear) etc. with Tonsillar hypertrophy grade 3 or 4 were included in the study.

Continuous data were summarized in form of mean and SD. Difference in means was analysed using Student t-test.

Each patient underwent tonsillectomy by cold dissection method on one side and by ultrasonic scalpel on other and this was decided by odd even method of randomization. Microscope was used for tonsillectomy on either side. On the side assigned to the Harmonic scalpel, tonsillectomy was performed using the hook blade (Harmonic scalpel, Synergy, Ethicon Endosurgery, LLC Guaynabo, Puerto Rico 00,969 USA). In cold dissection method done by eve’s tonsillar snare.

Outcomes were Assessed as Follows

Measurement of Operation Time

Operating time was defined from the time of incision at anterior pillar till the achievement of haemostasis separately in both tonsillar fossae and measured by chronometer.

Measurement of intraoperative blood loss [19].

Estimated intraoperative blood loss was calculated by calorimetric method of estimation (swab weighting technique):

Weight of gauze balls before use in grams = y.

Weight of gauze balls after use (soaked with blood) in grams = x.

Weight of blood lost in grams = x − y.

Specific gravity of blood = 1.055.

Quantity of blood lost in ml = x − y/1.055.

Amount of fluid (blood + known quantity of saline) collected in suction bottle in ml = a.

Amount of saline sucked in the bottle in ml = b.

So quantity of blood in suction bottle in ml = a − b.

Total quantity of blood lost in ml (z) = x − y/1.055 + a − b.

Measurement of pain score⁽⁹⁾:

Pain score was obtained using standard visual analog pain score from 0 (no pain) to 10 (worst pain). The patients and their parents were asked to fill in the assessment form in the ward.

Pain was estimated by using visual analogue scale which is as following:

Post-operative pain score was assessed for both the sides separately by the observer and documented using visual analogue scale after 24 h of operation. Evaluation of tonsillar fossa for haemorrhage was also performed at the same time.

All patients that had no complications whatsoever were discharged after 48 h as per institutional protocol and called for follow up in the outpatient department after a week.

On follow up, pain score was noted, the patients were asked for any complaints and tonsillar fossa examination was done. Any post-operative haemorrhage was also noted and the patients were called for follow up in the outpatient department after a week.

described by other authors, [7,8,9,10] five scores were considered: 1,2,3,4,5 according to the size of the slough in comparison with the areal size of the post-operative tonsillar bed.

Healing score	Size of the slough in comparison with the areal size of the post-operative tonsillar bed (percentage)
1	0%
2	1 – 25%
3	26 – 50%
4	51—75%
5	100%

Healing is inversely proportional to slough present in tonsillar fossa. So a lower healing score shows minimum slough and better healing and a higher healing score shows more slough and worse healing.

In each patient Mean operation time, Mean volume of blood loss,Analogue score for post-operative pain at 24hrs and 7th postoperative day and Healing of wound on 14th post-operative day were recorded and observed.

Result

A total of 40 cases with ages between 4–14 years and mean age of 8 years were studied in which 31 were males (77.5%) and 9 were females (22.5%). As regards surgery, both Harmonic scalpel tonsillectomy and Cold dissection tonsillectomy were done in the same patient, so age and gender distribution has no effect in comparison of outcomes.

Operating Time

The Operating time for Harmonic Tonsillectomy in terms of mean and SD was significantly lower (8.29 + 2.67 min.) as compared to that in Cold Dissection Tonsillectomy (12.59 + 5.17 min.) and this difference was found to be statistically significant on application of t test (p < 0.001) (Table 1, Fig. 1).

Table 1.

Operation time (min)

Operation time(min.)
Group	N	Mean	SD	Median	Minimum	Maximum	P value
Cold Dissection Tonsillectomy	40	12.59	5.17	11.72	5.02	27.32	< 0.001
Harmonic Tonsillectomy	40	8.29	2.67	8.03	4.27	15.9

Fig. 1.

Operation time

Blood Loss (ml)

The Blood loss of Harmonic Tonsillectomy in terms of mean and SD was lower (4 ± 1.84 ml) as compared to that in Cold Dissection Tonsillectomy (37.53 ± 18.96 ml) and this difference was found to be statistically significant on application of t test (p < 0.001) (Table 2, Fig. 2).

Table 2.

Blood loss (ml)

Blood loss (ml)
Group	N	Mean	SD	Median	Minimum	Maximum	P value
Cold dissection Tonsillectomy	40	37.53	18.96	30.50	8	79	< 0.001
Harmonic Tonsillectomy	40	4.00	1.84	3.00	1	8

Fig. 2.

Blood loss

Post-Operative Pain Score (Day 1)

The post-operative pain score after 24 h of Harmonic Tonsillectomy in terms of mean and SD was lower (4.10 + 1.80) as compared to that after Cold Dissection Tonsillectomy (6.18 + 2.24) and this difference was foundto be statistically significant on application of t test (p < 0.001) (Table 3, Fig. 3).

Table 3.

Post-Operative pain score (Day 1)

Post op pain score (Day 1)
Group	N	Mean	SD	Median	Minimum	Maximum	P value
Cold Dissection Tonsillectomy	40	6.18	2.241	6.00	1	10	< 0.001
Harmonic Tonsillectomy	40	4.10	1.795	4.00	1	8

Fig. 3.

Post-Operative pain score (Day 1)

Post-Operative Pain Score (Day 7)

The Post-operative pain scoreafter 7^th day of Harmonic Tonsillectomy in terms of mean and SD was lower (2.08 + 1.42) as compared to that in Cold Dissection Tonsillectomy (2.58 + 1.60) and this difference was foundnotto be statistically significant on application of t test (p = 0.154) (Table 4, Fig. 4).

Table 4.

Post-operative pain score (Day 7)

Post op pain score (Day 7)
Group	N	Mean	SD	Median	Minimum	Maximum	P value
Cold Dissection Tonsillectomy	40	2.58	1.599	3.00	0	6	0.154
Harmonic Tonsillectomy	40	2.08	1.421	2.00	0	5

Fig. 4.

Post-Operative pain score (Day 7)

Post-Operative Wound Healing score (Day 14)

The Wound Healingscore on 14^th post-operative day of Harmonic Tonsillectomy in terms of mean and SD was Higher (1.40 + 0.55) as compared to that in Cold Dissection Tonsillectomy (1.30 + 0.46) and this difference was foundnot to be statistically significant on application of t test (p = 0.380) (Table 5, Fig. 5).

Table 5.

Post-operative wound healing score (Day 14)

Wound Healing Score (day 14)
Group	N	Mean	SD	Median	Minimum	Maximum	P value
Cold Dissection Tonsillectomy	40	1.30	.464	1.00	1	2	0.380
Harmonic Tonsillectomy	40	1.40	.545	1.00	1	3

Fig. 5.

Post-Operative Wound Healing score (Day 14)

Discussion

Ideally, tonsillectomy should be painless and associated with minimal blood loss and with low post-operative morbidity in terms of diet and resuming daily activities. In reality, however the morbidity of tonsillectomy may be significant.As regards the surgical technique, improving the intraoperative efficiency and reducing post-operative morbidity are the most common parameters in assessing the best method in this procedure.Differences among surgical methods are described in terms of intra-operative blood loss, operative time, post-operative pain, healing of tonsillar fossa and particularly, post-operative morbidity.

For more than a century, traditional dissection tonsillectomy has remained the gold standard for tonsil removal. Traditional tonsillectomy leaves the wound open to heal by secondary intention, thus causes pain and bleeding as two major postoperative complications. This is the reason pioneers usually concentrate on decreasing these two problems by comparing various techniques. Long periods of wound recoveries, taking up to fifteen days, are not so uncommon. This may bear the risk of bleeding from tonsillar bed. Postoperative pain can cause severe limitation in regaining daily activities and normal diet.

The ultrasonic scalpel has several theoretical advantages over blunt dissection tonsillectomy when electro cautery is used for haemostasis. It should cause less blood loss as the vibrating blade coagulates small vessels as it cuts. This in turn should lead to a decrease in the use of diathermy for haemostasis and with this an associated decrease in operating time. As the ultrasonic scalpel coagulates at temperatures between 50 °C and 100 °C,there should also be less thermal damage and with this there may be a decrease in post-operative pain.

We conducted a prospective comparative study in which 40 patients of age group 4–14 years (mean age 8 years) with bilateral Grade 3 or 4 tonsillar hypertrophy with concurrent adenoid hypertrophy were included. The patients.

underwent tonsillectomy on one side using the ultrasonic scalpel, and on the other by Cold dissection under vision of microscope. The side to undergo tonsillectomy using the Harmonic scalpel was determined by odd–even method of randomisation. Adenoidectomy was done in all patients by micro-debrider with help of 70⁰tele-laryngoscope per-orally. No data related to adenoidectomy were included in the study.

Mean age of subjects in our study was 8.00 ± 2.60 years with 77.5% males and 22.5% females.

The mean operating time in our study in Harmonic group was found to be 8.29 ± 2.67 min which is lesser in Cold Dissection group was 12.59 ± 5.17 min (Table 2). This difference was found to be statistically significant on application of t-test (p < 0.001).

Collison P J et al. (2002) [11] also concluded after a prospective double blinded study on 28 patients that Harmonic scalpel tonsillectomy takes less time (7.7 ± 1.2 min.) in comparison to Cold dissection tonsillectomy (10.9 ± 1.66) with p value = 0.002. Kamal SA et al. (2005) [12] did a study on 180 patients and found that operation time in HST (14.9 ± 1.94 min.) was less as compared to CDT (26.16 ± 1.91 min.) but found no significant difference. Other studies like Salomone R et al.(2007) [13] Lachanas V A et al. (2007) [14] and Karimi E et al. (2017) [15] also noted a statistically lower mean operation time on the Harmonic scalpel tonsillectomy side (p < 0.001).

So operation time results in our study were found to be similar to earlier studies as Harmonic scalpel technique of tonsillectomy is significantly faster than Cold dissection tonsillectomy.

In our study,the mean blood loss on Harmonic scalpel tonsillectomy side was 4.00 ± 1.84 ml lesser as compared to that on Cold dissection tonsillectomy side which was 37.53 ± 18.96 ml and this difference was found to be statistically significant on application of t test (p < 0.001).

Collison P J et al. (2002) [11] noted a significantly less blood loss in Harmonic tonsillectomy (6.2 ± 4.14 ml) as compared to conventional tonsillectomy (58.8 ± 11.31 ml). Kamal S A et al. (2005) [12] noted less bleeding in Harmonic tonsillectomy (6.2 ± 2.54 ml) as compared to Cold knife tonsillectomy (49.38 ± 3.4 ml) with p value = 0.05. other studies like Sugiura N et al. (2002) [16], Oko M O et al. (2005)²⁹ [13], Salomone R et al.(2007) [13] and Lachanas V A et al. (2007) [15] also found harmonic scalpel tonsillectomy safe in terms of blood loss (p < 0.001). Karimi E et al. (2017) [15] observed blood loss on Harmonic tonsillectomy side 9.59 ± 16.7 ml to be significantly less than that on conventional tonsillectomy side 74.38 ± 271.8 ml(p < 0.001).

The difference between the blood loss noted in the two different methods corresponds to the results of the older studies, however it was significantly less in our study owing to the use of the microscope.

In our study, the mean pain score after 24 h of Harmonic scalpel tonsillectomy was 4.10 ± 1.80 lesser as compared to that of Cold dissection tonsillectomy which was 6.18 ± 2.24. Thus it was found that immediate post op pain was less in Harmonic scalpel tonsillectomy as compare to that in Cold dissection and this difference was found to be statistically significant on application of t test (p < 0.001).

Collison P J et al. (2002) [11] observed a lesser pain score in Harmonic tonsillectomy (3.5 ± 0.99) as compared to that in Cold dissection tonsillectomy (4.4 ± 0.94).).Salomone R et al. (2007) [13] noted lesser pain after 24 h of Harmonic tonsillectomy without significant difference from Cold dissection tonsillectomy. Other studies of Lachanas V A et al. (2007) [14], Karimi E et al. (2017) [15], Sugiura N et al. (2002) [16] and Oko M O et al. (2005) [17] noted more pain score on day 1 after Harmonic tonsillectomy than that after Cold dissection Tonsillectomy but the difference was not significant (p < 0.001).

So, the finding regarding the post-operative day 1 pain score in our study was similar to that in most of the previous studies.

In our study, the mean pain score on 7 h post-operative day after Harmonic scalpel tonsillectomy was 2.08 ± 1.42 as compared to that after Cold dissection tonsillectomy which was 2.58 ± 1.60. Thus it was found that late post-op pain was less in Harmonic scalpel tonsillectomy as compare to Cold dissection but the difference was found not to be statistically significant on application of t test (P = 0.154).

Salomone R et al. (2007) [13] and Lachanas V A et al. (2007) [14] noted significantly lesser pain on 7^thpost-operative day of Harmonic scalpel tonsillectomy (2.6 ± 1.7 and 3.29 ± 1.3) as compared to that after Cold dissection tonsillectomy (4.3 ± 1.62 and 5.33 ± 1.25) with p < 0.001. Collison P J et al. (2002) [11] calculated a higher pain score after 1 week of Harmonic tonsillectomy (2.7) than that after Cold dissection tonsillectomy (2.6) in their study but the difference was not significant (p = 0.925). Similar results were found in study by Sugiura N et al. (2002) [16] (pain score in HST = 3.8 and CDT = 3.1, p = 0.41). Oko M O et al. (2005) [17] also measured a higher pain score in Harmonic technique than that in Cold dissection tonsillectomy (1.7 v/s 1.33) but the difference was not significant. Karimi E et al. (2017) [15] also found a higher pain score on Harmonic side (3.09 ± 2.22) as compared to that on Conventional tonsillectomy side (2.59 ± 1.91), p value was 0.368.

So pain score after 1 week of surgery varies from study to study and our results are comparable to only some of the previous studies.

In our study, the mean wound healing score on 14 h post-operative day after Cold dissection tonsillectomy was 1.3 ± 0.46 as opposed to that after Harmonic scalpel tonsillectomy which was1.4 ± 0.55. However, no significant difference was noted as p value was 0.380. Thus post-operative wound healing was better in Cold dissection tonsillectomy compare to Harmonic scalpel tonsillectomy.

Ragab S M et al. (2012) [7] recorded tonsillar fossa healing by using 5 categories (i.e. 0 per cent slough, 1–25 per cent slough, 26–50 per cent slough, 51–75 per cent slough and 76–100 per cent slough) on the 7th, 14th and 21st post-operative day. He found that tonsillar fossa healing rate of the cold dissection group did not differ significantly from that of the ultrasonic scalpel group. Davidoss N H et al. (2018) [18, 19] summarised the available literature related to wound healing post tonsillectomy and concluded that cold steel dissection minimises tissue damage to surrounding structures, allowing for quicker healing but further research is needed.

Summary and Conclusion

Traditional dissection tonsillectomy has for long been considered the gold standard for tonsil removal, however, it is not devoid of its own problems. Intra-operative and post-operative complications and morbidities are not as unusual as one might suppose. This is, therefore an active area of research. A new technique for tonsillectomy should be an improvement over the existing techniques in terms of morbidity and mortality,postoperative pain, intraoperative blood loss, time and should carry a lower risk of post-operativehaemorrhage.

One of the novel techniques is tonsillectomy with harmonic scalpel whichtheoretically has less intra-operative bleeding, a decrease in the use of diathermy and a reduced operating time. The thermal damage and post-operative pain are also less.

The use of microscope further decreases volume of blood loss during surgery and post-operative haemorrhage as microstructures and plane of dissection are more clearly visible because of better illumination and magnification. Thus none of our patient complained of post-operative haemorrhage.

In the field of tonsillectomy surgeries trends have been traced by surgeons from conventional “cold dissection” method to “modern” day techniques electro-cautery, coblation and harmonic scalpel and surgeons have observed evolution of techniques to reduce post-operative haemorrhage. Although there are evolution of techniques still outcomes can be dramatically improve with the knowledge and expertise of the surgeon.

In our study, Harmonic tonsillectomy had better outcome with respect to operation time, intraoperative blood loss, post-operative pain and post-operative haemorrhage when compared to cold dissection tonsillectomy. In view of Wound healing, cold dissection tonsillectomy was found to be better than Harmonic scalpel tonsillectomy.