Effect of morphine on splanchnic blood flow.

Abstract

Splanchnic blood flow was measured by the constant infusion of indocyanine green given before and after morphine 0.2 mg/kg (maximum 15 mg) i.v. in 13 patients. Splanchnic blood flow increased from 1012 .+-. 98 ml/min to 1200 .+-. 118 ml/min after the administration of morphine, a 19% increase (P < 0.025). Splanchnic vascular resistance decreased from 0.094 .+-. 0.010 to 0.081 .+-. 0.010 mmHg min/ml, a 16% decrease (P < 0.001). There was no significant change between baseline and post-morphine values in systemic arterial pressure (92.2 .+-. 3.8 and 89.0 .+-. 2.9 mmHg), hepatic vein wedge pressure (7.1 .+-. 1.0 and 7.8 .+-. 0.6 mmHg) or right atrial mean pressure (4.5 .+-. 0.6 and 4.3 .+-. 0.7 mmHg). Morphine induced significant splanchnic arteriolar dilatation.