Comparing venous to arterial base deficit during hemorrhage and resuscitation

Abstract

Arterial base deficit is used in assessing trauma patient oxygen debt, life saving intervention requirements, resuscitation adequacy, and mortality risk. Venous blood samples are simpler and less painful to obtain than arterial samples. Theoretically, venous base deficit values might substitute for arterial values. Methods: 8 anesthetized, ventilated dogs were hemorrhaged (H, 90min mean arterial pressure [MAP]=35-40mmHg or MAP<30mmHg>10min or MAP<25mmHg>1min), hypotensively stabilized (S, 120min enalaprilat 0.01mg/kg/hr + hemoglobin based oxygen carrier [HBOC] or 7.8% hypertonic saline dextran 70 [HSD] for MAP=40-45mmHg), resuscitated (60min lactated Ringer’s for MAP=75-80mmHg), monitored (60min no fluids), and euthanized. Arterial and venous base deficit were measured every 30 minutes using the clinical laboratory and a point of care device. Results: Almost all venous base deficit values were larger than matched arterial values. The smallest arterial to venous differences detected with the two different measurement methods matched. Conclusions: When systemic blood flow is high, venous base deficit can be used in lieu of arterial. When blood flow is low, venous base deficit values do not reflect arterial values.