Peritonsillar infiltration with levobupivacaine for posttonsillectomy pain relief: does concentration have any effect? A double-blind randomized controlled clinical study.

OBJECTIVE Post-tonsillectomy pain is believed to be mediated by noxious stimulation of C-fiber afferents located in the peritonsillary space, and local anesthetic infiltration to this area may decrease pain by blocking the sensory pathways and thus preventing the nociceptive impulses. We aimed to compare the effects of different concentrations of preincisional peritonsillar levobupivacaine (0.25% and 0.5%) infiltration on postoperative pain and bleeding in a placebo-controlled design. PATIENTS AND METHODS After obtaining Institutional Ethics Committee approval, 72 ASA I-II patients between 3 and 12 years of age, scheduled to undergo tonsillectomy were enrolled and randomly assigned to one of the three groups using the sealed envelope technique, as Group I (Control group), Group II, and Group III receiving preincisional bilateral peritonsillar infiltration with saline, 0.25% levobupivacaine and 0.5% levobupivacaine, respectively (3 mL to each tonsil). Pain, fever, dysphagia; nausea-vomiting and hemorrhage were evaluated at postoperative 0, 30, and 60 minutes and 2, 6, 12, and 24 hours. Oral paracetamol was administered at a dose of 15 mg/kg when FLACC score was > 4. The number of paracetamol administrations within the first 24 hours were recorded. RESULTS The patients in Groups I, II and III defined pain (FLACC > 4) at a rate of 87%, 60.9%, and 54.2% within the postoperative first 24 hours, respectively. The total number of additional analgesic requirements was significantly low in Group II and III when compared with Group I. There was no difference between groups in terms of fever, dysphagia, nausea-vomiting, hemorrhage. CONCLUSIONS Both concentrations (0.50% and 0.25%) of levobupivacaine were found to be equally safe and effective during preincisional peritonsillar infiltration in children. NCT number: 02322346.