Partial attenuation of the pressor response to endotracheal intubation. A comparison of the effects of intravenous clonidine and fentanyl.

In a randomized, double-blind placebo controlled study, intravenous clonidine, fentanyl and saline were compared for both their effect on the cardiovascular response to intubation, and early post-operative pain. The patients treated with fentanyl and clonidine were more sedated and the requirements for induction agents were lower compared to the control group. On intubation, both the active treatments resulted in a smaller increase in both heart rate and mean arterial pressure compared to the control group. There was no significant difference in recovery times in the three groups. Although the time to first request for analgesia was longer in the clonidine group compared to both the fentanyl and saline groups, the difference in morphine requirements between the groups was not significant. The differences between the two active treatments were not significant, and clonidine offered no additional benefits over fentanyl for this purpose.