Effects of combined intravenous nicardipine and diltiazem administration on the circulatory response to laryngoscopy and tracheal intubation

To evaluate the effect of combined intravenous administration of the calcium antagonists, nicardipine and diltiazem, on the circulatory responses to tracheal intubation, the mean arterial pressure (MAP) and rate pressure product (RPP) in response to laryngoscopy following tracheal intubation were compared in patients receiving saline placebo or nicardipine 10 μg·kg⁻¹ and diltiazem 0.1 mg·kg⁻¹ 60 s before the initiation of laryngoscopy. Each group was comprised of ten patients undergoing elective surgery. The patients receiving saline showed a significant increase in MAP and RPP associated with tracheal intubation. However, these increases were significantly attenuated (P<0.05) in the patients to whom nicardipine and diltiazem were administered concurrently.