[Monitoring kidney function in abdominal infection]

In ICU patients suffering from abdominal sepsis acute renal failure (ARF) is a common (50% incidence) and often lethal (more than 80% mortality) complication. Continuous monitoring of renal function is necessary for both adequate fluid replacement and early detection of ARF. Using a programmable handheld computer the following parameters are calculated at least daily: creatinine, osmolal and free water clearance, fractional excretion of sodium and potassium and non-saline loss. The clearance values are corrected to 1.73 m2 body surface area. Free water clearance proved to be a particularly valuable guide for fluid therapy as well as for early diagnosis of ARF. In all septic patients renal function is impaired to some degree, since despite increased cardiac output creatinine clearance is only normal or even decreased. More than 50% of our patients with abdominal sepsis develop ARF, resulting in a dramatic increase in mortality. Goal of renal monitoring in sepsis is to detect ARF as early as possible and to differentiate between extrarenal and septic origin to enable immediate surgical treatment.