Comparison of the haemostatic and cardiovascular effects of adrenaline and ornithine-8-vasopressin (POR 8) in middle ear operations.

The local haemostatic and cardiovascular effects of ornithine-8-vasopressin (POR 8) 5.5 IU and adrenaline 350 microng were compared in middle ear operations in combined and methoxyflurane anaesthesia. The study was double-blind. Adrenaline had statistically significantly better haemostatic properties than POR 8 and the method of anaesthesia did not affect the difference between adrenaline and POR 8. With both methods of anaesthesia adrenaline increased systolic arterial pressure and pulse rate, and transiently increased and then decreased diastolic arterial pressure. In contrast to adrenaline, POR 8 markedly increased diastolic arterial pressure and decreased pulse rate. All the parameters studied, the vasoconstrictors, the methods of anaesthesia as well as the times of measuring statistically significantly affected the changes both in systolic and diastolic arterial pressures. Only the methods of anaesthesia markedly affected the changes in the pulse rate. Transient electrocardiographic changes occurred from 6% to 17% in different groups.