Despite tonsillectomy is one of the most common surgical procedures performed by an otolaryngologist through various techniques, postoperative bleeding and pain remain complications of this operation. The otolaryngologists try to practice and compare different procedures of tonsillectomy to achieve the best way regarding the shorter operative time with less blood loss, avoidance of intra and postoperative complications including mainly post-tonsillectomy hemorrhage and pain. We aimed to compare the diode laser and coblation tonsillectomy both in children and adults. The strength of the study was the use of both procedures in the same patient (coblation on one side and diode laser on the other side) to lessen the bias. Similar studies used 2 methods of tonsillectomy in the same patient (11)(18). The study revealed that the coblation was better than the diode laser method regarding the shorter operative time and less blood loss during the procedure. However, the diode laser was superior to the coblation tonsillectomy concerning postoperative pain.
Although coblation and laser tonsillectomies are relatively new techniques, if one compares them with the cold steel dissection method, they have gained popularity in the otolaryngology practice owing to the advancement in the technology of their machines.
In Iraq, few randomized controlled trials studied the comparison between the cold steel dissection method with CO2 laser (19), coblation and bipolar diathermy (12), and coblation versus dissection method (20). This study was the first study in Iraq compared the diode laser and coblation tonsillectomy in children and adults.
Powell et al. in 1997 studied the effect of radiofrequency on the tissue of the tongue in animal models, both in vitro and in vivo. They concluded that radiofrequency can reduce the volume of the tongue in a perfect and controlled way (21). Since that time, many otolaryngologists start the use of coblation tonsillectomy in their daily clinical practice (12)(22)(18). The outcomes were good in studies involving a small size of patients (22)(18). Moreover, many randomized controlled studies comparing the coblation with other techniques of tonsillectomy revealed the superiority of this kind over other procedures regarding the operative time, amount of intraoperative blood loss, and postoperative pain (14)(15). Basu et al. study reported that harmonic scalpel tonsillectomy is better than coblation in the following parameters operative time, intraoperative blood loss volume, and postoperative bleeding (5). Accordingly, the study is considered this method as an advanced way of tonsillectomy. Other studies reported equivocal results with other procedures.
In a study from China by Zhou et al.(13), they compare retrospectively the coblation (300 patients) with coblation and tie tonsillectomy (215 patients) in the adult population regarding the operative time, blood loss during the procedure, post-tonsillectomy pain and complications, and full recovery and return to normal activities. The study concluded that the coblation tonsillectomy alone was statistically significantly superior to coblation with tie regarding all the above-mentioned parameters except post-tonsillectomy bleeding, coblation with a tie was significantly less post-operative bleeding than coblation tonsillectomy alone.
A recent systematic review study by Ahmed and Arya (23) reviewed 15 randomized controlled trial articles that studied tonsillectomy by laser or other procedures. They reported that the majority of laser tonsillectomy was performed by CO2 laser (n = 665, 60.3%), followed by potassium-titanyl-phosphate (KTP) laser (n = 238, 21.6%), and the least diode laser (n = 199, 18.1%). While, tonsillectomies performed by other techniques were 792 (64.7%) by cold dissection, 238 (19.4%) by diathermy, and 194 (15.8%) by coblation method. They concluded that there is an overall improvement in laser tonsillectomy in comparison with other techniques and this may be due to increased familiarity with laser surgeries and increment in the number of laser centers across the globe. However, our study revealed that the coblation tonsillectomy was better than the diode laser regarding the operative time and blood loss volume during surgery. The better results of coblation in comparison with diode laser in operative time and intraoperative blood loss may be attributed to the larger probe size of the coblation handle with a wider surface area of effect concerning the diode laser handle. Similar findings were observed in previous studies (14)(15). But the results of our study (significantly lower VAS scores of postoperative pain in diode laser in comparison with coblation technique) in contrast to the above-mentioned studies concerning postoperative pain. The significantly less postoperative pain at least in the first postoperative week with diode laser may be due to the precise cut with less necrotic tissues and less damage to surrounding structures.
A recent study by Kumar et al. (24) reported that the operative time and bleeding during surgery were significantly low for CO2 laser in comparison with the cold steel dissection tonsillectomy group. Pain score was comparable in early post-operative days but was high towards the end of the first week. Our results revealed that the pain scores were significantly less in the laser group in the first 7 days post-tonsillectomy in comparison with coblation (P-value < 0.05). While at 2 weeks, there was no statistically significant difference (P-value = 0.392) between the two groups. This may be attributed to two causes, firstly, the laser has a desensitizing effect on the cut ends of the nerve fibers in the few postoperative days, thereafter, the pain sensation is increased. Secondly, the thermal effect of the laser needs more time to heal, in addition to the formation of a thick slough in the tonsillar area with possible late-onset of contraction and pain (25). Of note, secondary infection may occur beneath the thick slough layer with the increased chances of the development of secondary hemorrhage. Therefore, it is suggested to use a prophylactic antibiotic in the post-tonsillectomy period by many researchers to avoid such complications.
Post-tonsillectomy bleeding (primary or secondary) is a major complication of tonsillectomy with variable incidences (0.95%-7.8%) among previous investigations (2)(8)(5)(14)(26). The difference in these incidences may be attributed to the following; type of tonsillectomy, primary or secondary bleeding, children or adult patients, and whether an antibiotic is used as prophylactic or not. Many investigations have observed different incidences of delayed post-tonsillectomy bleeding between children and adults, with more incidence in adults than children (2) (8). Fortunately, our study didn’t report a case of post-tonsillectomy bleeding. This may be an incidental finding.
The parameters in defining the improvement of tonsillectomy operation are shorter operative time, less intraoperative blood loss, low incidence of primary or secondary post-tonsillectomy bleeding, less postoperative pain, and early recovery and return to usual activities. Despite, many researchers studied these parameters among various tonsillectomy methods (12)(13)(14)(18), there is still no consensus about the best method of tonsillectomy. Therefore, the following factors should be taken into consideration when choosing the tonsillectomy procedure; availability of devices and instrumentations, the experience of the surgeon, preference of the patients or parents, and the cost of the procedure.
Although the current study tried to avoid result bias by comparing the two sides of the same patient still it did not bypass the intrapersonal differences in size, fibrosis, and blood supply between the two tonsils of the same patient. This actually cannot be overcome and may have some effect on the results but the arbitrary selection of the sides may minimize this effect. Even though the time in preparing the 2 devices didn't take into consideration when calculating the operative time in the current study, it had a drawback on the patients as it prolongs the total operative time with its risk of anesthesia. Therefore, we don't advise using 2 techniques of tonsillectomy in the same patient in daily clinical practice as here we used them for research purposes.