OXYGEN-UPTAKE OXYGEN-SUPPLY DEPENDENCY - FACT OR FICTION

More than a decade ago, observations of co-variance between VoverdotO( 2) and DoverdotO(2) led to the identification of a condition known as pathological O-2 Supply dependency. This condition was subsequently ob served in critically ill patients with sepsis and acute circulatory fa ilure. More recently, other authors have challenged the existence of t his condition, often citing methodological problems or mathematical co upling to account for spurious observations in the earlier studies. He re, we review the evidence for and against pathological O-2 supply dep endency. We find that many of the arguments have some validity but onl y in specific circumstances. We conclude, therefore, that pathological O-2 supply dependency is a hallmark of acute circulatory failure and that an effective therapeutic approach should be based on an evaluatio n of organ system function in each individual case. Parameters such as blood lactate, pHi and veno-arterial PCO2 may be useful in this respe ct.