Early course of microcirculatory perfusion in eye and digestive tract during hypodynamic sepsis (Critical Care)

IntroductionThe aim of the study is to evaluate and compare the microcirculatory perfusion during experimental sepsis in different potentially available parts of the body, such as sublingual mucosa, conjunctiva of the eye, mucosa of jejunum and rectum. Methods: Pigs were randomly assigned to sepsis (n=9) and sham (n=4) groups. The sepsis group received a fixed dose of alive Escherichia coli infusion over 1 hour (1.8 * 109 /kg colony-forming units). Animals were observed 5 hours after the start of Escherichia coli infusion. In addition to systemic hemodynamic assessment, we performed conjunctival, sublingual, jejunal and rectal evaluation of microcirculation using Sidestream Dark Field (SDF) videomicroscopy at the same time points: at baseline, 3 and 5 hours after the start of live Escherichia coli infusion. Assessment of microcirculatory parameters of convective oxygen transport (microvascular flow index (MFI) and proportion of perfused vessels (PPV)), and diffusion distance (perfused vessel density (PVD) and total vessel density (TVD)) was done using a semi-quantitative method. Results: Infusion of Escherichia coli resulted in a hypodynamic state of sepsis associated with low cardiac output and increased systemic vascular resistance despite fluid administration. Significant decrease in MFI and PPV of small vessels were observed in sublingual, conjunctival, jejunal and rectal lodges 3 and 5 hours after start of Escherichia coli infusion in comparison to baseline variables. Correlation between sublingual and conjunctival (r=0.80, p=0.036), sublingual and jejunal (r=0.80, p=0.044), sublingual and rectal (r=0.79, p=0.03) MFI was observed 3 hours after onset of sepsis. However, this strong correlation between the sublingual and other regions disappeared 5 hours after the start of Escherichia coli infusion. Overall, the sublingual mucosa exhibited the most pronounced alterations of microcirculatory flow in comparison to conjunctival, jejunal and rectal microvasculature (p