Abstract Sa505: Cerebral Oxygen Saturation Measurement Using Near-Infrared Spectroscopy During In-Hospital Cardiac Arrest Predicts Early Outcome

Introduction: The effectiveness of cardiopulmonary resuscitation is dependent on maintaining optimal cerebral perfusion. NIRS provides a non-invasive method of monitoring cerebral oxygen saturation (rSO2), providing real-time information on the quality of resuscitation. Dynamics of rSO2 changes in the peri-resuscitation period and depending on the drugs administered have not yet been fully investigated. Hypothesis: It was assumed that continuous monitoring of rSO2 using NIRS during CPR can serve as an indicator of resuscitation quality and outcome. Moreover, a positive correlation between rSO2 and EtCO2 was assumed. Goals: The aim of the study was to assess the dynamics of rSO2 changes during CPR and in the period up to 24 hours after successful resuscitation. Moreover, the relationship between rSO2 and EtCO2 levels and ROSC was determined, as well as the influence of adrenaline and NaHCO3 supply on rSO2 values. Methods: A prospective observational study was performed at the University Hospital in Krakow (Poland). The study included 104 consecutive patients who experienced IHCA. The rSO2 and EtCO2 levels were monitored (using Masimo Open Connect™ MOC-9™). CPR was performed by the Early Response Team. Once ROSC was obtained rSO2 and EtCO2 monitoring were continued for 24 hours or until cardiac arrest resumed. Patients were divided into three groups: no ROSC, ROSC with survival < 30 days, ROSC with survival ≥ 30 days. Results: ROSC was achieved in 54 patients and survival was ≥30 days in 16 patients. It was found that rSO2 values were statistically significantly higher during the entire CPR process in patients with ROSC compared to patients without ROSC (p<0.001). See Figure 1. A positive correlation was obtained between EtCO2 and rSO2 in the ROSC group. There were no significant changes in rSo2 values after the administration of adrenaline and NaHCO3 (p=0.604). Conclusions: Monitoring rSO2 during CPR can be a valuable prognostic tool. Higher rSO2 values correlate positively with the achievement of ROSC, demonstrating the effectiveness of real-time NIRS measurements as an indicator of effective cerebral perfusion. The average rSO2 values after adrenaline administration remained at a similar level in all groups. Cerebral oxygen saturation remains a more stable measurement than EtCO2.