EFFECT OF OXYGEN INHALATION ON SYSTEMIC, CENTRAL, AND SPLANCHNIC HEMODYNAMICS IN CIRRHOSIS

Background/Aims: Patients with cirrhosis exhibit a hyperdynamic circul ation with increased cardiac output and low arterial blood pressure. T he aim of the present study was to assess the effects of oxygen inhala tion on systemic, central, and splanchnic haemodynamics and vasoactive systems in patients with cirrhosis (n = 19). Results: Spirometry was normal, but the carbon monoxide diffusing capacity (transfer factor) w as significantly decreased, 18.8 ml . min(-1). mmHg(-1) (-32% of that predicted, p < 0.0001), and correlated significantly with the cardiac output (r = 0.78, p < 0.0005), plasma volume (r = 0.72, p < 0.001) and the central and arterial blood volume (r = 0.67, p < 0.005). After in halation of 100% oxygen over a period of 20 min, the cardiac output de creased from 7.4 to 6.6 l/min (p < 0.0005), and the systemic vascular resistance increased from 980 to 1124 dyn . s . cm(-5) (p < 0.005). Th e change in systemic vascular resistance was significantly greater in patients with mild liver dysfunction than in those with severe liver d ysfunction (p < 0.02). In contrast, no significant changes were seen i n the arterial portal venous pressures during inhalation of oxygen. Ar terial concentrations of catecholamines, renin, endothelin-l, and calc itonin gene-related peptide were all increased in patients with cirrho sis, but only the catecholamine concentrations decreased significantly (noradrenaline -13%, p < 0.02 and adrenaline -16%, p < 0.01) in respo nse to oxygen. Conclusion: During oxygen inhalation cardiac output dec reases and systemic vascular resistance increases in association with a decrease in arterial concentrations of catecholamine, but oxygen sup ply in patients with cirrhosis does not normalise the hyperdynamic cir culation or the low arterial blood pressure.