Noninvasive continuous cardiac output and cerebral perfusion monitoring in term infants with neonatal encephalopathy: assessment of feasibility and reliability

Background Noninvasive hemodynamic monitoring of infants with neonatal encephalopathy (NE) undergoing therapeutic hypothermia (TH) would be a potentially useful clinical tool. We aimed to assess the feasibility and reliability of noninvasive cardiac output monitoring (NICOM) and near-infrared spectroscopy (NIRS) in this cohort. Methods NICOM and NIRS were commenced to measure cardiac output (CO), systemic vascular resistance (SVR), blood pressure (BP), and cerebral regional oxygen saturations (SctO 2 ) during TH and rewarming. NICOM measures of CO were also compared with simultaneous echocardiography-derived CO (echo-CO). Results Twenty infants with a median gestation of 40 weeks were enrolled. There was a strong correlation between NICOM- and echo-CO ( r 2 =0.79, P <0.001). NICOM-CO was systematically lower than echo-CO with a bias of 27% (limits of agreement 3–51%). NICOM illustrated lower CO during TH, which increased during rewarming. SctO 2 increased over the first 30 h of TH and stayed high for the remainder of the study. There was a rise in SVR over the first 30 h of TH and a decrease during rewarming (all P <0.05). Conclusions Noninvasive hemodynamic assessment of infants with NE is feasible and illustrates potentially important changes. Larger studies are needed to assess the clinical applicability of those methods in this cohort.