Comparison of two different local anaesthetic infiltrations for postoperative pain relief in tonsillectomy: a prospective, randomised, double blind, clinical trial

In previous studies, it was shown that the post-tonsillectomy wound infiltration of bupivacaine can reduce postoperative pain. The objective of this study is to determine whether the postoperative wound infiltration with a mixture of bupivacaine, mepivacaine and adrenaline is more effective than the sole application of bupivacaine. A prospective, double-blind, randomized, control study included 30 patients scheduled for "cold steel" tonsillectomy. All patients obtained post-tonsillectomy infiltration of 6.25 mg bupivacaine alone on one side and 3.75 mg bupivacaine, 25 mg mepivacaine and 0.0125 mg epinephrine on the other side (intra-individual study design). Intake of analgesics and postoperative pain was assessed 0-6 days after surgery by visual analogue scale in inactivity and during swallowing by the nurse staff. Bleeding, dysphagia, pain, aspiration or extraordinary pain sensation were registered by the patient. The pain scores did not differ between the groups. All patients received systemic painkillers; 6 (20%) patients needed intravenous analgesics. Postoperative haemorrhage occurred in two patients without correlation to a certain local anaesthetic. Two patients developed sinus tachycardia for 2.5 min after epinephrine infiltration. Because of cost-effectiveness and complication rates, we recommend only post-tonsillectomy wound infiltration of bupivacaine. The injection should be placed in superficial muscle and connective tissue. A stringent systemic analgesia regime is indispensable for pain relief after tonsillectomy.