Assessment of cardiac output in children: A comparison between the pressure recording analytical method and Doppler echocardiography*

Objective To assess cardiac output in pediatric patients with the pressure recording analytical method (PRAM) and the Doppler echocardiography method. PRAM derives cardiac output from beat-by-beat analysis of the arterial pressure profile (systolic and diastolic phase) in the time domain. Design A prospective observational study. Setting Pediatric intensive care unit at a tertiary care children's hospital. Patients Forty-eight patients between the ages of 1 month and 18 yrs. Interventions Femoral or radial artery catheterization and mechanical ventilation. Measurements and main results Cardiac output was simultaneously estimated by Doppler echocardiography and PRAM. Cardiac output values obtained by Doppler echocardiography (2.7 +/- 1.6 L/min, range 0.92-8.20) were significantly correlated with those estimated by PRAM (2.6 +/- 1.7 L/min, range 0.89-7.48; r2 = .99, p < .01). The mean difference between the two estimates was 0.12 +/- 0.27 L x min(-1) (95% confidence interval, -0.54 to 0.77 L x min(-1)). Conclusions In the range of ages evaluated, PRAM provides reliable estimates of cardiac output when compared with noninvasive techniques.