A noninvasive method for monitoring cerebral perfusion during cardiopulmonary resuscitation

Abstract

Purpose: This study evaluates the use of transcranial Doppler (TCD) ultrasound in assessing the changes experienced by the cerebral circulation during cardiopulmonary resuscitation (CPR) and compares it with measurements of internal carotid artery (ICA) flow rates (ultrasonic flow-meter measurements) and cerebral blood flow (CBF) (radioactive-microsphere measurements) in a porcine cardiac arrest model undergoing closed chest CPR. Methods: Sixteen piglets were anesthetized and subjected to TCD monitoring, ICA flow-rate measurements, and CBF measurements during CPR following induction of ventricular fibrillation. A total of 14 comparisons between TCD and CBF measurements, and 36 comparisons between TCD and ICA flow measurements were performed. Correlations were determined using Pearson's method, and the validity of the correlation was determined using Bonferoni's adjusted probabilities. Results: The correlation between mean cerebral blood flow velocity and mean total ICA flow rate was 0.67 ( P < .01). The correlation between peak systolic blood flow velocity and CBF was 0.76 ( P = .02). Conclusions: TCD can provide on-line information about cerebral perfusion during CPR.