Incidence of low central venous oxygen saturation during unplanned admissions in a multidisciplinary intensive care unit: an observational study

INTRODUCTION: It has been shown that early central venous oxygen saturation (ScvO(2))-guided optimization of hemodynamics can improve outcome in septic patients. The early ScvO(2 )profile of other patient groups is unknown. The aim of this study was to characterize unplanned admissions in a multidisciplinary intensive care unit (ICU) with respect to ScvO(2 )and outcome. METHODS: Ninety-eight consecutive unplanned admissions to a multidisciplinary ICU (median age 63 [range 19 to 83] years, median Simplified Acute Physiology Score [SAPS II] 43 [range 11 to 92]) with a clinical indication for a central venous catheter were included in the study. ScvO(2 )was assessed at ICU arrival and six hours later but was not used to guide treatment. Length of stay in ICU (LOS(ICU)) and in hospital (LOS(hospital)) and 28-day mortality were recorded. RESULTS: ScvO(2 )was 70% ± 12% (mean ± standard deviation) at admission and 71% ± 10% six hours later (p = 0.484). Overall 28-day mortality was 18%, LOS(ICU )was 3 (1 to 28) days, and LOS(hospital )was 19 (1 to 28) days. Patients with an ScvO(2 )of less than 60% at admission had higher mortality than patients with an ScvO(2 )of more than 60% (29% versus 17%, p < 0.05). Changes in ScvO(2 )during the first six hours were not predictive of LOS(ICU), LOS(hospital), or mortality. CONCLUSION: Low ScvO(2 )in unplanned admissions and high SAPS II are associated with increased mortality. Standard ICU treatment increased ScvO(2 )in patients with a low admission ScvO(2), but the increase was not associated with LOS(ICU )or LOS(hospital).