DEPENDENCE OF OXYGEN-CONSUMPTION ON OXYGEN DELIVERY IN CHILDREN WITH HYPERDYNAMIC SEPTIC SHOCK AND LOW OXYGEN EXTRACTION

We studied the effect of increasing systemic oxygen delivery (DO2) by packed RBC (PRBC) transfusion on oxygen consumption (VO2) in children with hyperdynamic septic shock. After routine resuscitation with volume loading and pharmacologic support, patients were studied if they had significant derangements of oxygen transport variables defined as: baseline VO2 <180 ml/min·m2 and oxygen extraction (O2 extr) <24%. Eight studies were performed. PRBC transfusion increased DO2 from 636 ± 167 to 828 ± 266 ml/min·m2 (p < .01) without increasing cardiac index (5.2 ± 1.3 vs. 5.0 ± 1.4 L/min·m2). VO2 increased from 112 ± 36 to 157 ± 60 ml/min·m2 (p < .01) while O2 extr was unchanged (18 ± 3% vs. 19 ± 6%). Despite initial low O2 extr, VO2 can be increased in pediatric septic shock by a further increase in DO2. Since VO2 correlates with survival, one should consider enhancing DO2 further despite initial low O2 extr and high DO2. Effects on morbidity and mortality require further study.