Correlation between Regional Cerebral Saturation and Invasive Cardiac Index Monitoring after Heart Transplantation Surgery

Abstract

AbstractThe present study assessed the correlations between cerebral regional saturation detected by near infrared spectroscopy (NIRS) and cardiac index (CI) measured by pulmonary artery catheter. This was a retrospective cohort study conducted in the cardiac intensive care unit in a tertiary care children's hospital. Patients younger than 18 years of age who underwent heart transplantation and had a pulmonary artery catheter on admission to the pediatric cardiac intensive care unit between January, 2010, and August, 2013, were included. There were no interventions. A total of 10 patients were included with median age of 14 years (range, 7–17). Indications for transplantation were dilated cardiomyopathy (n = 9) and restrictive cardiomyopathy (n = 1). Mixed venous oxygen saturation (SvO2), cerebral regional tissue saturation (rSO2), and CI were recorded hourly for 8 to 92 hours post-transplantation. Spearman's rank correlation coefficient was used to assess correlations between SvO2 and cerebral rSO2 and between CI and cerebral rSO2. A total of 410 data points were collected. Median, 25th and 75th percentiles of cerebral rSO2, CI, and SvO2 were 65% (54–69), 2.9 L/min/m2 (2.2–4.0), and 75% (69–79), respectively. The correlation coefficient between cerebral rSO2 and CI was 0.104 (p = 0.034) and that for cerebral rSO2 and SvO2 was 0.11 (p = 0.029). The correlations between cerebral rSO2 and CI and between cerebral rSO2 and SvO2 were weak. Cerebral rSO2 as detected by NIRS may not be an accurate indicator of CI in critically ill patients.