Abstract

This thesis focuses on the microcirculation in critically ill children. The aim was to evaluate whether the microcirculation is affected during critical illness, to study if any microcirculatory alterations normalize over time with therapeutic intervention, and to assess whether microcirculatory alterations are related to outcome. The microcirculation was evaluted using the video microscopy techniques Orthogonal Polarization Spectral imaging and/or Sidestream Dark Field imaging, as well as by dynamic arterial lactate indices that incorporate the duration or the trend over time, next to the magnitude of lactate derangement. The critically ill patient groups and therapeutic interventions of interest are: children with therapy-resistant primary respiratory failure requiring extracorporeal membrane oxygenation, neonates with congenital diaphragmatic hernia who require catecholaminergic treatment, and children with return of spontaneous circulation after cardiac arrest who require therapeutic hypothermia.