Prevention of rigidity during fentanyl-oxygen induction of anesthesia

Twenty patients who underwent open heart surgery were divided into two groups of 10 patients each. Patients of both groups received fentacyl infused to a total dose of 2.5 mg. Patients in group 2 received pancuronium infused to a total dose of 10 mg. Nine patients in group 1 became rigid. None of the patients in group 2 became rigid (P<0.001). In group 1 there was a significant increase in mean pulmonary arterial pressure (MPAP) and a significant fall in mean arterial pressure (MAP). Both MPAP and MAP remained stable in the patients of group 2.