Neutrophil elastase suppression by medium-molecular-weight hydroxyethylstarch in orthopaedic surgery

The aim of this study was to compare the effect of hydroxyethylstarch (HES) and human albumin solution (HAS) on human neutrophil elastase (HNE) release in patients undergoing elective knee replacement surgery.

Forty-three patients (ASA 1 or 2) were randomly allocated into two groups. Group A (n = 21) received 5 ml/kg of 4.5% HAS pre-operatively and a further 5 ml/kg HAS as an intraoperative replacement. Postoperatively the patients received Ringers' lactate at the discretion of the anaesthetic team. Group B was given 5 ml/kg HES (Fresenius-Kabi) preoperatively and a further 5 ml/kg HES intra-operatively. Thereafter fluid management was as in group A. Arterial blood samples were taken preoperatively and at 5 minutes, 30 minutes, 60 minutes, 120 minutes, 240 minutes and 24 hours post-tourniquet release for HNE and arterial blood gas analysis. Repeated measures of analysis of variance established a significant difference in the pattern of change of HNE levels (log transformed) and the PaO₂/FiO₂ ratios with time between the two groups. Follow-up t tests revealed significantly lower levels of HNE (Table 1) and also significantly higher PaO₂/FiO₂ ratios in Group B post-tourniquet release.

Table 1 (abstract P407)

In conclusion, the results suggest that infusion of HES lowers HNE release from activated neutrophils in postoperative knee replacement patients and may lead to less lung injury.