Can Cerebral Regional Oxygen Saturation (rSO2) be used as an Indicator of the Quality of Chest Compressions in Patients with Cardiopulmonary Arrest? A Study Evaluating The Association between rSO2 and Mean Arterial Pressure: The PRESS Study

Background: Sudden cardiac arrest causes numerous deaths worldwide. High-quality chest compressions are important for good neurological recovery. Arterial pressure is considered useful to monitor the quality of chest compressions by the American Heart Association. However, arterial pressure catheter might be inconvenient during resuscitation. Conversely, cerebral regional oxygen saturation (rSO2) during resuscitation may be associated with a good neurological prognosis. Therefore, we aimed to evaluate the correlation between mean arterial pressure and rSO2 during resuscitation to use rSO2 as the indicator of the quality of chest compressions.Methods: This study was a single-centre, prospective, observational study. Patients with out-of-hospital cardiac arrest who were transported to a tertiary care emergency centre between October 2014 and March 2015 in Japan were included. The primary outcome was the regression coefficient between MAP and rSO2. MAP and rSO2 were measured during resuscitation (at hospital arrival [0 min], 3 min, 6 min, 9 min, 12 min, 15 min), and MAP was measured by an arterial catheter inserted into the femoral artery. For analysis, we used the higher value of rSO2 obtained from the left and right forehead of the patient and measured using a near-infrared spectrometer. Regression coefficients were calculated using the generalized estimating equation (GEE) with MAP and SAP as response variables and rSO2 as an explanatory variable, because MAP and rSO2 were repeatedly measured in the same patient. Since the confounding factors between MAP or SAP and rSO2 were not clear clinically or from previous studies, the GEE was analysed using univariate analysis.Results: Thirty-seven patients were analysed. rSO2 and MAP during resuscitation from hospital arrival to 15 min later were expressed as follows (median [interquartile range]): rSO2, 29.5 (24.3–38.8) %, and MAP, 36.5 (26–46) mmHg. The regression coefficient (95% confidence interval) of log-rSO2 and log-MAP was 0.42 (0.03–0.81) (p=0.035).Conclusion: rSO2 and MAP showed a mild but statistically significant association. rSO2 could be used to assess the quality of chest compressions during resuscitation as a non-invasive and simple method.Trial registration: This study was registered in the University hospital Medical Information Network Clinical Trials Registry (UMIN000015479).

Can Cerebral Regional Oxygen Saturation (rSO2) Be Used as an Indicator of the Quality of Chest Compressions in Patients With Cardiopulmonary Arrest? A Study Evaluating the Association Between rSO2 and Mean Arterial Pressure: the PRESS Study

Background: Sudden cardiac arrest causes numerous deaths worldwide. High-quality chest compressions are important for good neurological recovery. Arterial pressure is considered useful to monitor the quality of chest compressions by the American Heart Association. However, arterial pressure catheter might be inconvenient during resuscitation. Conversely, cerebral regional oxygen saturation (rSO2) during resuscitation may be associated with a good neurological prognosis. Therefore, we aimed to evaluate the correlation between mean arterial pressure and rSO2 during resuscitation to use rSO2 as the indicator of the quality of chest compressions.Methods: This study was a single-centre, prospective, observational study. Patients with out-of-hospital cardiac arrest who were transported to a tertiary care emergency centre between October 2014 and March 2015 in Japan were included. The primary outcome was the regression coefficient between MAP and rSO2. MAP and rSO2 were measured during resuscitation (at hospital arrival [0 min], 3 min, 6 min, 9 min, 12 min, 15 min), and MAP was measured by an arterial catheter inserted into the femoral artery. For analysis, we used the higher value of rSO2 obtained from the left and right forehead of the patient and measured using a near-infrared spectrometer. Regression coefficients were calculated using the generalized estimating equation (GEE) with MAP and SAP as response variables and rSO2 as an explanatory variable, because MAP and rSO2 were repeatedly measured in the same patient. Since the confounding factors between MAP or SAP and rSO2 were not clear clinically or from previous studies, the GEE was analysed using univariate analysis.Results: Thirty-seven patients were analysed. rSO2 and MAP during resuscitation from hospital arrival to 15 min later were expressed as follows (median [interquartile range]): rSO2, 29.5 (24.3–38.8) %, and MAP, 36.5 (26–46) mmHg. The regression coefficient (95% confidence interval) of log-rSO2 and log-MAP was 0.42 (0.03–0.81) (p=0.035).Conclusion: rSO2 and MAP showed a mild but statistically significant association. rSO2 could be used to assess the quality of chest compressions during resuscitation as a non-invasive and simple method.Trial registration: This study was registered in the University hospital Medical Information Network Clinical Trials Registry (UMIN000015479).

Cerebral Tissue Regional Oxygen Saturation as a Valuable Monitoring Parameter in Pediatric Patients Undergoing Extracorporeal Membrane Oxygenation

Objective: Brain function monitoring technology for extracorporeal membrane oxygenation (ECMO) support has been developing quite slowly. Our objective was to explore the data distribution, variation trend, and variability of cerebral tissue regional oxygen saturation (CrSO2) in pediatric patients undergoing ECMO.Methods: Eight patients who received venoarterial ECMO (V-A ECMO) were included in our study. All of them accepted continuous CrSO2 monitoring by near-infrared spectroscopy (NIRS) within 12 h of ECMO initiation until ECMO wean. Differences in the CrSO2 distribution characteristic, the variation trend of daily CrSO2, and the variability of CrSO2 for the first 5 days following ECMO initiation were compared between survivors and non-survivors according to pediatric intensive care unit (PICU) mortality.Results: The percentage of time of CrSO2 <60% against the whole monitoring time was significantly lower in survivors in both hemispheres {right: 4.34% [interquartile range (IQR) = 0.39–8.55%] vs. 47.45% [IQR = 36.03–64.52%], p = 0.036; left: 0.40% [IQR = 0.01–1.15%] vs. 30.9% [IQR = 26.92–49.62%], p = 0.036}. Survivors had significantly higher CrSO2 on the first 4 days. Root mean of successive squared differences (RMSSD), the variability variable of CrSO2, was significantly lower in survivors (right: 3.29 ± 0.79 vs. 6.16 ± 0.67, p = 0.002; left: 3.56 ± 1.20 vs. 6.04 ± 1.44, p = 0.039).Conclusion: Lower CrSO2, CrSO2 <60% over a longer period of time, and higher fluctuation of CrSO2 are likely associated with PICU mortality in pediatric patients undergoing V-A ECMO.Clinical Trial Registry: URL: http://www.chictr.org.cn/showproj.aspx?proj=46639, trial registry number: ChiCTR1900028021.

Usefulness of Simultaneous Measurement of Brain and Muscle rSO2 (Regional Oxygen Saturation) in Shock Patients: a Report of Three Cases

BackgroundIn the field of emergency medical care, we often experience a situation in which we cannot measure pulse oximetric saturation (SpO₂) or blood pressure due to circulatory failure associated with shock. However, as we can measure rSO₂ values of the brain even in patients with shock, we hypothesized that we could evaluate the oxygen supply-demand balance between brain and muscle tissue by simultaneously measuring regional oxygen saturation (rSO₂) values of the brain and muscle tissue of patients with shock.Case presentationWe attached a TOS-OR rSO₂ monitor (TOSTEC CO., Tokyo, Japan) to 10 healthy volunteers and measured the rSO₂ values of their brain and muscle for 3 minutes. The rSO₂ values of their brain cerebral regional oxygen saturation (crSO₂) and muscle regional oxygen saturation (mrSO₂) were 77.6±1.6% and 76.2±1.3% (mean ± SD). There was little difference between crSO₂ and mrSO₂ (cerebro-musculoskeletal difference in regional saturation of oxygen; c-mDrSO₂). However, there were discernible amount of c-mDrSO₂ in three cases with shock, Case 1 showed a prolonged shock state due to septic shock caused by bacterial pneumonia. Her crSO₂ values was always higher than her mrSO₂ value, and there was a c-mDrSO₂. Case 2 showed a decrease in mean arterial pressure (MAP) with the development of septic shock caused by intestinal perforation. His crSO₂ value was higher than that of his mrSO₂, and c-mDrSO₂ increased with the decrease of his MAP. Case 3 had a low MAP due to hemorrhagic shock caused by postpartum hemorrhage. Her crSO₂ value was higher than that of her mrSO₂ and a c-mDrSO₂ was present. After resuscitation, the c-mDrSO₂ decreased with the increase in her blood pressure.ConclusionWe evaluated the usefulness of simultaneous measurement of crSO₂ and mrSO₂ as an objective and non-invasive method in shock management. Even if SpO₂ or blood pressure could not be measured due to circulatory failure associated with shock, it was possible to measure the values of crSO₂ and mrSO₂, which changed in real time with fluctuation of the blood pressure. Unlike previous monitoring devices, the rSO₂ monitor may continuously and clearly reflect the changes in local oxygen supply-demand balance.