Base deficit and oxygen transport in severe preeclampsia.

OBJECTIVE

To evaluate the relationship of anaerobic metabolism, as reflected by the calculated base deficit, with oxygen transport and left ventricular function in women with severe preeclampsia.

METHODS

Forty women with singleton pregnancies and severe preeclampsia who met prescribed criteria for invasive hemodynamic monitoring had arterial blood gas and hemodynamic values obtained immediately after placement of a pulmonary artery catheter. Oxygen transport indices were stratified according to the admission base deficit.

RESULTS

Linear regression analysis demonstrated a strong negative correlation between the calculated base deficit and the oxygen delivery index (r = -0.64), cardiac index (r = -0.62), and left ventricular stroke work index (r = -0.58). A baseline maternal base deficit exceeding -8.0 mEq/L consistently predicted fetal acidosis, fetal death, and maternal end-organ ischemic injury.

CONCLUSION

The calculated base deficit reliably reflects maternal oxygen transport dynamics and identifies patients at risk for end-organ injury. Ventricular contractility and oxygen delivery decline with mounting oxygen debt.