Microcirculatory events in ischemia/reperfusion of the pancreas defined by continuous tissue oximetry

In ischemia/reperfusion of the pancreas impairment of microcirculation after reperfusion is believed to be of critical importance. The 'no-reflow' phenomenon is thought to cause persisting tissue ischemia, while the 'reflow-paradox' is defined as secondary impairment of nutritive perfusion. These phenomena have been shown by intravital microscopy but their effect on tissue oxygenation as assessed by continuous tissue oximetry has not been identified. In landrace pigs tissue oxygenation was investigated in warm ischemia/reperfusion of the pancreas by the use of continuous tissue oximetry. After reperfusion rapid reoxygenation occurred which was followed by a period of secondary hypoxia. Thereafter, secondary reoxygenation was found, and finally tertiary hypoxia with a gradual decline of tissue pO(2) was noted. The data show a relevant impairment of tissue oxygenation after reperfusion. However, 'no-reflow' seems not to be a primary failure of capillary reperfusion but the consequence of a short reperfusion period followed by secondary ischemia. The 'reflow-paradox' most likely corresponds to tertiary ischemia.