Acid-base determinants of survival after cardiopulmonary resuscitation.

The acid-base and electrolyte conditions which favor survival were examined in 105 patients during and after CPR. There was a sharp decrease in survival when arterial pH exceeded 7.55 during the initial 10 min after initiation of CPR. Measurements made one hour after successful resuscitation also demonstrated an increase in mortality when pH exceeded 7.55. Arterial blood lactate also served as a sensitive quantitative indicator of prognosis, both during and one hour after successful CPR. The adverse effects of alkalemia were largely explained by increases in whole-blood bicarbonate, plasma sodium, and plasma osmolality after administration of sodium bicarbonate.