Comparison of the cardiorespiratory effects of ketorolac and alfentanil during propofol anaesthesia.

The cardiorespiratory effects of a new nonopioid analgesic, ketorolac tromethamine, were compared with alfentanil as part of a balanced technique in which anaesthesia was maintained by a constant infusion of propofol. Twenty patients were allocated randomly to receive a single dose of either ketorolac 30 mg or alfentanil 0.5 mg. The study medication was given during the anaesthetic when the rate of ventilation had been stable (+/- 1 b.p.m.) for 5 min. Measurements of ventilatory rate, end-tidal carbon dioxide partial pressure, arterial oxygen saturation (SaO2), heart rate and systemic arterial pressure were made at 1-min intervals for 15 min following the test drug. Patients having alfentanil developed significant decreases in ventilatory rate, heart rate and mean arterial pressure. A significant increase in end-tidal carbon dioxide partial pressure occurred also. No changes occurred in any of the measured variables in the ketorolac group.