Is the degree of multiple organ dysfunction related to severity of capillary leakage?

Introduction

Multiple organ dysfunction syndrome (MODS) is believed to result from microcirculatory failure in surgical intensive care patients. We hypothesised that degree of MODS is mirrored by severity of capillary leakage assessed by venous congestion plethysmography.

Methods

Twenty-two patients with MODS [1] (moderate MODS group: less and equal 8 points, n = 13; severe MODS group: greater and equal 9 points, n = 9) were studied. All patients were monitored including a pulmonary artery catheter and a gastric tonometer during the study. Fluid filtration capacity and isovolumetric venous pressure were assessed using a electromechanical sensor with automated calibration for strain-gauge plethysmography (Filtrass 2001, Domed GmbH, Germany). In addition, arterial lactate concentrations, arterial-, mixed venous blood gas analysis and systemic hemodynamics were measured and systemic oxygen transport variables calculated. For statistical analysis paired Student's t-test and in cases of non-normal distribution the Wilcoxon signed-ranked test was performed. P-values < 0.05 were considered significant. Data are given as means ± SD.

Results

There were no differences in age, systemic oxygen delivery, consumption and oxygen extraction ratio between groups. Mortality in patients with moderate MODS was 15.4%, in patients with severe MODS 55.6% (P = 0.049). Patients with high MODS demonstrated significantly higher arterial lactate concentrations (4.5 ± 3 mmol/l) when compared with moderate MODS (1.7 ± 0.9 mmol/l; P = 0.04). There was a trend towards higher capillary filtration coefficients in patients with severe MODS (5.33 ± 2.04 ml/min/100 ml/mmHg × 10^-3) when compared to moderate MODS (4.02 ± 1.48 ml/min/100 ml/mmHg × 10^-3; P = 0.062).

Conclusion

Patients with severe MODS have a tendency towards higher capillary filtration coefficients suggesting increased capillary leakage. Neither systemic oxygen transport parameters nor tonometrically derived variables demonstrated any differences between MODS-groups despite significant differences in patients mortality.