Effects of glossopharyngeal nerve block on pain control after tonsillectomy: a systemic review and meta-analysis

We investigated the role of perioperative intraoral glossopharyngeal nerve block to minimize postoperative pain in patients undergoing tonsillectomy through a meta-analysis of the relevant literature.

We retrieved eight studies from PubMed, Scopus, Embase, Web of Science, and Cochrane databases up to August 2023. We compared perioperative glossopharyngeal nerve block with a control group, in order to examine postoperative pain, analgesic use, and other postoperative morbidities.

Postoperative pain was significantly reduced at 1-4 h (SMD -1.26, 95% CI [-2.35; -0.17], I² = 94.7%, P = 0.02) and 5-8 hours (SMD -1.40, 95% CI [-2.47; -0.34], I² = 96.1%, p = 0.01) in the treatment groups compared to the control group. However, glossopharyngeal nerve block showed no efficacy in reducing pain or use of analgesic drugs after 12 h compared to the control group. The incidences of postoperative bleeding (OR 0.95, 95% CI [0.35; 2.52], I² = 0.0%), local agent toxicity (OR 4.14, 95% CI [0.44; 38.63], I² = 0.0%), nasal problems (OR 1.25, 95% CI [0.60; 2.61], I² = 0.0%), postoperative nausea and vomiting (OR 1.35, 95% CI [0.78; 2.33], I² = 0.0%), swallowing difficulty (OR 1.61, 95% CI [0.76; 3.42], I² = 56.0%), and voice change (OR 3.11, 95% CI [0.31; 30.80], I² = 0.0%) were not significantly different between the treatment and control groups. The treatment group showed higher prevalence of respiratory problems and dry mouth compared to control without statistical significance, but a significant increase in throat discomfort (p = 0.02).

Intraoral glossopharyngeal nerve block for tonsillectomy did not significantly impact postoperative pain management and was associated with some adverse effects with increases in respiratory problems, dry mouth, and throat discomfort compared to controls.