Changes in the sublingual microcirculation and endothelial adhesion molecules during the course of severe meningococcal disease treated in the paediatric intensive care unit

The sublingual microcirculation can be visualised in real time using sidestream dark-field (SDF) imaging. Endothelial activation mediated through adhesion molecules may alter flow patterns in the microcirculation. We studied sublingual microcirculatory disturbances in children with meningococcal disease (MCD) and simultaneously measured plasma levels of adhesion molecules.

Twenty children admitted to the paediatric intensive care unit (PICU) with MCD were studied. Forty healthy children were controls. The sublingual microcirculation was assessed at admission and at timed intervals until extubation. The microvascular flow index (MFI), capillary density (CD), proportion of perfused vessels (PPV) and perfused vessel density (PVD) were measured using SDF imaging. Plasma intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin and P-selectin were measured at admission and at timed intervals during the course of PICU treatment.

Significant reductions in MFI, CD, PPV and PVD were found in children with MCD compared with controls (p < 0.005). These differences had resolved prior to extubation. Initial MFI values predicted the duration of mechanical ventilation, irrespective of the stage of illness at the time of presentation to PICU. There were negative correlations between the ICAM-1, VCAM-1 and E-selectin levels and the microcirculatory MFI and PPV values at the time of admission to PICU (p < 0.005).

Microcirculatory dysfunction is present in children with severe MCD with improvement alongside clinical recovery. Microcirculatory dysfunction correlated with markers of endothelial activation. Sublingual SDF imaging is feasible in children ventilated on PICU for severe sepsis and may prove useful in studies assessing illness severity and therapy.