Hypertonic versus isotonic crystalloid infusion for cerebral perfusion pressure in a porcine experimental cardiac arrest model

Abstract

Background: The effect of intravenous (IV) fluid administration type on cerebral perfusion pressure (CePP) during cardiopulmonary resuscitation (CPR) is controversial. The purpose of this study was to evaluate the association between IV fluid type and CePP in a porcine cardiac arrest model.

Methods: We randomly assigned 12 pigs to the hypertonic crystalloid, isotonic crystalloid and no-fluid groups. After 4 min of untreated ventricular fibrillation (VF), chest compression was conducted for 2 cycles (CC only). Chest compression with IV fluid infusion (CC + IV) was followed for 2 cycles. Advanced life support, including defibrillation and epinephrine, was added for 8 cycles (ALS phase). Mean arterial pressure (MAP), intracranial pressure (ICP) and CePP were measured. A paired t-test was used to measure the mean difference in CePP.

Results: Twelve pigs underwent the experiment. The hypertonic crystalloid group showed higher CePP values than those demonstrated by the isotonic crystalloid group from ALS cycles 2 to 8. The MAP values in the hypertonic group were higher than those in the isotonic group starting at ALS cycle 2. The ICP values in the hypertonic group were lower than those in the isotonic group starting at ALS cycle 4. From ALS cycles 2 to 8, the reduction in the mean difference in the isotonic group was larger than that in the other groups.

Conclusion: In a VF cardiac arrest porcine study, the hypertonic crystalloid group showed higher CePP values by maintaining higher MAP values and lower ICP values than those of the isotonic crystalloid group.

Keywords: Cardiac arrest; Cardiopulmonary resuscitation; Cerebral perfusion pressure; Hypertonic crystalloid; Isotonic crystalloid.