Is the new, noninvasive, continuous cardiorespiratory monitoring reliable during neonatal ECMO?

Background: Advances in cardiorespiratory monitoring have made the extracorporeal membrane oxygenation (ECMO) technique safer for the patient. Noninvasive, continuous tools are available, although data on their applications in the neonatal ECMO setting are lacking. Objective: We retrospectively described the neonatal clinical application of this continuous, noninvasive ECMO monitor and compared the analyzed parameters from those derived from blood gas analysis. Materials and methods: We performed 897 h of cardiorespiratory monitoring during neonatal venoarterial-ECMO (VA-ECMO) for four patients affected by (cardio-) respiratory failure, to compare the reliability of a noninvasive, continuous monitoring Spectrum M4® (M4) (Spectrum Medical, Gloucester, England) to an invasive, intermittent co-monitoring with blood gas analyzer (Radiometer Medical ApS, Brønshøj, Denmark). Results: A range of 117 pairs (time-matched BGA-derived vs. M4-derived parameters) was retrospectively analyzed. T-test, linear regression and Bland–Altman analysis for hemoglobin, hematocrit, venous oxygen saturation, oxygen delivery, oxygen consumption, oxygen extraction ratio, oxygen partial pressure, and carbon dioxide partial pressure showed a strong relationship between the two monitors for all parameters analyzed (p < 0.0001). Conclusions: Continuous, noninvasive cardiorespiratory monitoring appears to be feasible and reliable, although its accuracy needs to be verified in a more extensive cohort.