HIGH-RISK SURGICAL ACUTE-RENAL-FAILURE TREATED BY CONTINUOUS ARTERIOVENOUS HEMODIAFILTRATION - METABOLIC CONTROL AND OUTCOME IN 60 PATIENTS

The outcome and metabolic control was studied in 60 critically ill pat ients with acute renal failure (ARF) treated by continuous arterioveno us hemodiafiltration (CAVHD) in a single surgical intensive care unit. Mean age(+/- SEM) was 60 +/- 2 years with a male predominance (80%). The majority of patients required mechanical ventilation (83%) and/or vasopressor support (70%) and suffered from multiorgan failure [mean n umber of organ system failures 3.3 +/- 0.3 (range 1-6)]. CAVHD resulte d in a rapid decline of serum urea and creatinine levels during the fi rst 72 h (urea 47.4 +/- 2.3 to 30.3 +/- 1.4 mmol/l, p < 0.05, and crea tinine 572 +/- 27 to 361 +/- 23 mu mol/l, p < 0.05); thereafter, contr olled steady-state levels were achieved with serum urea levels kept be low 30 mmol/l with full protein alimentation and often despite hypoten sion, surgery and septicemia. Significant electrolyte derangements cou ld be easily corrected and maintained within normal limits. Bicarbonat e homeostasis could be restored within 48 h in patients with severe me tabolic acidosis (HCO3- <20 mmol/l) with use of bicarbonate as a buffe ring anion (17 +/- 0.5 to 23.2 +/- 0.6, p < 0.05). CAVHD allowed rapid removal of excess body and lung water (up to 5 liters/day) without he modynamic instability. Despite a mean pretreatment APACHE II score of 26.5, 26 patients (43%) survived until discharge from the intensive ca re unit, of whom 23 (38%) survived to leave hospital. Requirement of m echanical ventilation or vasopressor support, higher APACHE II scores and septicemia were all associated with a poor prognosis. Although pro gnosis was inversely correlated with the number of organ system failur es, 24% of patients with 3 or more organ system failures survived to l eave hospital. Data suggest that CAVHD represents a significant advanc e in the management of critically ill patients with ARF and may have c ontributed to improved survival.