Adverse effects of prostacyclin administered directly into patients with combined renal and respiratory failure prior to dialysis.

We infused prostacyclin into 11 critically ill patients for 30 min at a rate of 5 ng/kg.min, prior to commencing prostacyclin haemodialysis. All patients had combined respiratory and renal failure and required intropic support. Despite the previous correction of hypovolaemia, prostacyclin produced a decrease in mean arterial pressure, pulmonary and systemic vascular resistances and cardiac filling pressures. There was no compensatory increase in cardiac output and due to an increase in pulmonary ventilation/perfusion mismatch an overall decrease in tissue oxygen delivery from a median of 560 ml/min.m2 to 370 ml/min.m2 was noted p less than 0.05, with a corresponding reduction in tissue oxygen uptake from 140 ml/min.m2 to 125 ml/min.m2. This was associated with an increase in both arterial hydrogen ion and lactate concentrations in 8 of the 11 patients studied, suggesting a deterioration in tissue oxygen supply/oxygen requirement. Prostacyclin should not be infused directly into patients unless monitored to assess the therapeutic/adverse effects on an individual patient basis.