EARLY MICROVASCULAR CHANGES IN SEPSIS AND SEVERE SEPSIS

Efforts to improve survival from sepsis are focusing increasingly on intervention during the earliest stages of this disease. The importance of derangements in microvascular flow in patients with established sepsis is well recognized. However, little data are available to describe microvascular changes in early sepsis. After research ethics committee approval, observational data were collected in healthy volunteers and within 6 h of presentation in patients with sepsis and severe sepsis. Sidestream dark-field imaging was used to obtain video images of the sublingual microcirculation. Cardiac index was measured using the noninvasive suprasternal Doppler method. Forty-eight patients and 16 healthy volunteers were recruited. Twenty-eight patients were diagnosed with sepsis and 19 with severe sepsis. Eight patients (17%) did not survive to leave hospital. For small vessels (<20 mu m), microvascular flow index (P < 0.05),heterogeneity index (P < 0.05) and the proportion of perfused vessels (P < 0.05) were lower in patients with sepsis and severe sepsis compared with healthy volunteers. Perfused vessel density (P < 0.05) was lower in the severe sepsis group compared with the sepsis group. The proportion of perfused vessels (P < 0.01) and MAP (P < 0.05) were lower in nonsurvivors compared with survivors. Sepsis results in derangements of microvascular flow, which can be identified in the early stages of this disease. These abnormalities are more marked in the most severely ill patients. Further research is required to fully characterize the effects of sepsis on microvascular function.