Diltiazem for prevention of acoustical trauma during otologic surgery.

100 patients were tested in a prospective, randomized, double-blinded study to assess the perioperative efficacy of a calcium channel blocker (diltiazem) in preventing acoustical trauma during otologic surgery. The patients were randomly divided into a therapy group (diltiazem) and a control group (placebo). Bone conduction hearing thresholds were examined preoperatively and again 1 day and 3 months postoperatively. Frequency-dependent changes in postoperative bone conduction and the number of patients with various degrees of postoperative hearing loss in both groups were statistically analyzed. The results indicated only a small postoperative hearing loss after ear surgery in both groups. There was a tendency for better results in the therapy group, but this was not statistically significant. Despite favorable results in animal trials utilizing different types of noise and the prophylactic application of diltiazem, further studies in humans are needed to determine the role of calcium antagonist drugs in the prophylaxis or treatment of acoustical trauma.