Retrospective study of the effect of haemofiltration on the outcome of patients with chronic liver disease with renal dysfunction

Introduction

Renal dysfunction is common in critically ill patients with chronic liver disease (CLD). The outcome of patients with CLD requiring ITU care with associated renal failure is poorly defined, as is their response to dose of renal replacement (CVVHF). We performed a retrospective study of 80 patients with CLD admitted to a specialist Liver Intensive Care Unit.

Methods

All patients admitted with chronic liver disease and receiving continuous haemofiltration were studied. We analysed data that had been acquired between January 1999 and November 2002 utilising the Riyadh ICU programme. The variables analysed were bilirubin, lactate, creatinine, APACHE II score, noradrenaline, and mechanical ventilation. Patients were divided into three groups. Group 1, low volume (LV) CVVHF (< 2 l exchange); Group 2, high volume (HV) CVVHF (> 2 l exchange); and Group 3, combination of HV and LV CVVHF. These three groups were subdivided as to whether they were receiving noradrenaline, mechanical ventilation or a combination of both.

Results

The survival rate in patients receiving LV and HV CVVHF or a combination of both was 9%. The subgroup survival is presented in Table 1.

Table 1

Patients receiving HV CVVHF, on noradrenaline, had a statistically significant higher lactate (P < 0.003) and APACHE II (P < 0.005) score when compared with those not on noradrenaline. Ventilated patients, on combination CVVHF, had significantly higher lactate (P < 0.02) and creatinine (P < 0.001) than nonventilated patients. There was no difference between early or late initiation of HV CVVHF. No patient with a lactate of greater than 3 mmol/l survived.

Conclusions

The outcome in our cohort of patients with chronic liver disease and receiving haemofiltration is extremely poor (9% survival). Our data shows the subgroup of patients on HV haemofiltration had 100% mortality rate. We have also shown that patients who require noradrenaline and ventilation in addition to RRT have a worse outcome. In addition, the timing of initiation of HV CVVHF does influence survival.