Objective: To evaluate efficacy and tolerability of enoximone, a phosphodiesterase inhibitor, in the treatment of cardiogenic shock.
Design: A prospective non randomized, non comparative study.
Setting: A general intensive care unit of a university hospital.
Patients: Six patients with cardiogenic shock (cardiac index < 2.5 l/min/m2, PWP > 15 mmHg) unsuccessfully treated with catecholamines.
Interventions: Enoximone was administered (0.5-1 mg/kg)by iv bolus according to clinical response (CI > or = 2.5 l/min/m2), then was continued by iv infusion (5-16 micrograms/kg/min). Dopamine infusion at low doses (3 micrograms/kg/min) was maintained during the study. In all patients a pulmonary artery catheter was inserted before the study began.
Measurements and main results: Direct and measured (using standard formula) haemodynamic parameters were registered. Basal data (before treatment) were compared with values after 30 minutes (bolus) and 8 hours (maintenance). CI (+57%) and O2 delivery (+74.7%) were significantly increased after 30 minutes and 8 hours, O2 extraction ratio normalized whereas heart rate and systemic blood pressure were unchanged.
Conclusions: Enoximone proved to be safe and effective in the treatment of cardiogenic shock. Its pharmacological effects combines inotropic and vasodilatant action without any change of heart rate thus avoiding an increase of O2 consumption in the jeopardized myocardium. Further studies will define better its routine use in critically ill patients with acute heart failure.