Put, intracardial and intrapulmonary volumes. Therefore monitoring of these parameters seems to be useful in risk patients and in other conditions of hypercirculation.P203 Is the degree of multiple organ dysfunction related to severity of capillary leakage?H Knotzer, W Pajk, A Mayr, M D ser, W Hasibeder Division of General and Surgical Intensive Care Medicine, Department of Anaesthesia and Critical Care Medicine, University of Innsbruck, Anichstra 35, A-6020 Innsbruck, Austria Introduction: Multiple organ dysfunction syndrome (MODS) is believed to result from microcirculatory failure in surgical intensive PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/20726384 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 (±)-BMS6462 site 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?) when compared to moderate MODS (4.02 ?1.48 ml/min/100 ml/mmHg ?10?; 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.Reference:1. Goris RJA, Te Boekhorst TPA, Nuytinck JKS, Gimbrere JSF: Multipleorgan failure. Arch Surg 1985, 120:1109-1115.Acknowledgement: Study supported by a Lorenz B ler Fonds 2000.Available online http://ccforum.com/supplements/6/SP204 Microvascular bed volume evaluated by near infrared spectroscopy in healthy and critically ill subjectsRA De Blasi, A Morelli, D Alampi, PF Bucci, R Pinto, C Berritta Cattedra di Anestesiologia e Rianimazione, I Universit? II Facolt?di Medicina e Chirurgia, Roma, Italy Introduction: The microvascular tone regulation can be very useful to be assessed to titrate therapy in critical conditions. In the present study, we use near infrared (NIR) spectroscopy in the frequency domain on critically ill patients and healthy subjects, to obtain the measurement of microcirculatory compliance and the regulation of vascular tone. Methods: Two groups of subjects have been studied: the first group was com.