Following preoperative written informed consent, patients presenting with a cardiac-index (CI) \< 2.2 l/min/m2 upon ICU-admission - despite adequate mean arterial (titrated with noradrenaline or sodium-nitroprusside) and filling pressures - will be randomized to 14 hour treatment with adrenaline or milrinone to achieve a CI \> 3.0 l/min/m2.
A group of patients not needing inotropes will be used as controls. Hemodynamics, metabolism (plasma lactate, pyruvate, glucose, acid-base status, insulin requirements) and renal function (urinary excretion of alpha-1-microglobulin, creatinine clearance, plasma cystatin-C levels) will be determined during the treatment period and up to 48 hours after surgery (follow up period).
The study is designed as a pilot study including 20 patients per group.
