Portable system for monitoring of regional cerebral oxygen saturation during prehospital cardiopulmonary resuscitation: a pilot study

Pre-hospital portable monitoring of cerebral regional oxygen saturation (rSO2) by ambulance personnel during cardiopulmonary resuscitation: A prospective observational analysis of 87 cases in Osaka city, Japan

Background

Regional cerebral oxygen saturation (rSO₂) is a non-invasive method of measuring cerebral perfusion; However, serial changes in cerebral rSO₂ values among out-of-hospital cardiac arrest (OHCA) patients in pre-hospital settings have not been sufficiently investigated. We aimed to investigate the association between the serial change in rSO₂ pattern and patient outcome.

Methods

We evaluated rSO₂ in OHCA patients using portable monitoring by emergency life-saving technicians (ELTs) from June 2013 to December 2019 in Osaka City, Japan. We divided the patterns of serial of rSO₂ change into type 1 (increasing pattern) and type 2 (non-increasing pattern). Patients in whom measurement started after return of spontaneous circulation (ROSC) were excluded. The outcome measures were ‘Prehospital ROSC’, ‘Alive at admission’, ‘1-month survival’ and ‘Cerebral Performance Category (CPC) 1 or 2′.

Results

Eighty-seven patients were eligible for this analysis (type 1: n = 40, median age: 80.5 [IQR: 72–85.5] years, male: n = 20 [50.0%]; type 2: n = 47, 81 [72–85.5] years, male: n = 28 [59.6%]). In a multivariable logistic regression adjusted for confounding factors, outcomes of ‘Prehospital ROSC’ and ‘Alive at admission’ were significantly higher in type 1 than type 2 pattern (11/40 [27.5%] vs. 2/47 [4.26%], AOR 5.67, 95% CI 1.04–30.96, p < 0.045 and 17/40 [42.5%] vs. 6/41 [12.8%], AOR 3.56, 95% CI 1.11–11.43, p < 0.033). There was no significant difference in ‘1-month survival’ and ‘CPC 1 or 2′ between patterns.

Conclusion

Type 1 (increasing pattern) was associated with ‘Prehospital ROSC’ and ‘Alive at admission’. Pre-hospital monitoring of cerebral rSO₂ might lead to a new resuscitation strategy.

Cerebral regional oxygen saturation during cardiopulmonary resuscitation and return of spontaneous circulation: A systematic review and meta-analysis

AIM

Predicting the return of spontaneous circulation (ROSC) during cardiopulmonary resuscitation in victims of cardiac arrest (CA) remains challenging. Cerebral regional oxygen saturation (rSO2) measured during resuscitation is feasible, and higher initial and overall values seem associated with ROSC. However, these observations were limited to the analysis of few small single-centre studies. There is a growing number of studies evaluating the role of cerebral rSO2 in the prediction of ROSC.

METHODS

We conducted an updated meta-analysis aimed at investigating the association of initial and overall values of cerebral rSO2 with ROSC after CA. We performed subgroups analyses according to the location of CA and conducted a secondary analysis according to the country where the study was conducted (resuscitation practice varies greatly for out-of-hospital CA).

RESULTS

We included 17 studies. Higher initial rSO2 values (11 studies, n = 2870, 16.6% achieved ROSC) were associated with ROSC: Mean Difference (MD) -11.54 [95%Confidence Interval (CI)-20.96, -2.12]; p = 0.02 (I² = 97%). The secondary analysis confirmed this finding when pooling together European and USA studies, but did not for Japanese studies (p = 0.06). One multi-centre Japanese study was an outlier with large influence on 95%CI. Higher overall rSO2 values during resuscitation (9 studies, n = 894, 33.7% achieving ROSC) were associated with ROSC: MD-10.38; [-13.73, -7.03]; p < 0.00001 (I² = 77%). All studies were conducted in Europe/USA.

CONCLUSIONS

This updated meta-analysis confirmed the association between higher initial and overall values of cerebral rSO2 and ROSC after CA. However, we found geographical differences, since this association was not present when Japanese studies were analysed separately.

Near-Infrared Spectroscopy Assessments of Regional Cerebral Oxygen Saturation for the Prediction of Clinical Outcomes in Patients With Cardiac Arrest: A Review of Clinical Impact, Evolution, and Future Directions

Despite three decades of advancements in cardiopulmonary resuscitation (CPR) methods and post-resuscitation care, neurological prognosis remains poor among survivors of out-of-hospital cardiac arrest, and there are no reliable methods for predicting neurological outcomes in patients with cardiac arrest (CA). Adopting more effective methods of neurological monitoring may aid in improving neurological outcomes and optimizing therapeutic interventions for each patient. In the present review, we summarize the development, evolution, and potential application of near-infrared spectroscopy (NIRS) in adults with CA, highlighting the clinical relevance of NIRS brain monitoring as a predictive tool in both pre-hospital and in-hospital settings. Several clinical studies have reported an association between various NIRS oximetry measurements and CA outcomes, suggesting that NIRS monitoring can be integrated into standardized CPR protocols, which may improve outcomes among patients with CA. However, no studies have established acceptable regional cerebral oxygen saturation cut-off values for differentiating patient groups based on return of spontaneous circulation status and neurological outcomes. Furthermore, the point at which resuscitation efforts can be considered futile remains to be determined. Further large-scale randomized controlled trials are required to evaluate the impact of NIRS monitoring on survival and neurological recovery following CA.

Effectiveness of the hemoglobin index for screening of subarachnoid hemorrhage in out-of-hospital cardiopulmonary arrest patients: a retrospective observational study

Aim

The hemoglobin index (HbI) represents the amount of hemoglobin, which reflects regional tissue blood volume. The HbI is calculated in real time by a regional oxygen saturation (rSO₂) monitor. For the hypothesis of our HbI project, we theorized that HbI could be a new method for the screening of subarachnoid hemorrhage (SAH) in overcrowded emergency departments. As a first step, this study aimed to clarify the effectiveness of HbI in screening SAH in out‐of‐hospital cardiopulmonary arrest (OHCA) patients using the rSO₂ data of our previous studies.

Methods

In this single‐center, retrospective, observational study, we examined HbI in patients with OHCA transferred to the Trauma and Acute Critical Care Center at Osaka University Hospital (Osaka, Japan) during the period between April 2013 and December 2015. A sensor attached to the patient's forehead monitored HbI continuously.

Results

Among 63 patients (40 men and 23 women; mean age, 76 [interquartile range (IQR), 66–85] years) with OHCA, five were diagnosed as having SAH (SAH group) and 58 were not (non‐SAH group). The HbI values were significantly higher in the SAH group than in the non‐SAH group (1.35 [IQR: 0.80–2.69] versus 0.41 [IQR: 0.32–0.61]), P = 0.0042). In the SAH group, with an HbI cut‐off value of 1.18, the specificity and sensitivity were 96% and 80%, respectively, and the area under the receiver operating characteristic curve of HbI was 0.89.

Conclusions

The HbI might be useful for the screening of SAH in patients with OHCA. The application of HbI in the emergency department could be expected in the future.

The relationship between cerebral regional oxygen saturation during extracorporeal cardiopulmonary resuscitation and the neurological outcome in a retrospective analysis of 16 cases

Background

In recent years, the measurement of cerebral regional oxygen saturation (rSO₂) during resuscitation has attracted attention. The objective of this study was to clarify the relationship between the serial changes in the cerebral rSO₂ values during extracorporeal cardiopulmonary resuscitation (ECPR) and the neurological outcome.

Methods

We measured the serial changes in the cerebral rSO₂ values of patients with out-of-hospital cardiac arrest before and after ECPR in Osaka National Hospital.

Results

From January 2013 through March 2015, the serial changes in the cerebral rSO₂ values were evaluated in 16 patients. Their outcomes, as measured by the Glasgow Outcome Scale (GOS) score at discharge, included good recovery (GR) (n = 4), vegetative state (VS) (n = 2), and death (D) (n = 10). In the poor neurological group (VS and D: n = 12; age, 52.8 ± 4.0 years), the cerebral rSO₂ values showed a significant increase during ECPR (5 min before ECPR: 52.0 ± 1.8%; 2 min before ECPR: 56.1 ± 2.3%; 2 min after ECPR: 63.5 ± 2.2%; 5 min after ECPR: 66.4 ± 2.2%; 10 min after ECPR: 67.6 ± 2.3% [P < 0.01]). In contrast, in the good neurological group (GR: n = 4; age, 53.8 ± 6.9 years), the cerebral rSO₂ values did not increase to a significant extent during ECPR (5 min before ECPR: 61.9 ± 3.1%; 2 min before ECPR: 57.1 ± 4.0%; 2 min after ECPR: 59.6 ± 3.8%; 5 min after ECPR: 61.0 ± 3.7%; 10 min after ECPR: 62.0 ± 3.8% [P = 0.88]). Our study suggested that the patients whose cerebral rSO₂ values showed no significant improvement after ECPR might have had a good neurological prognosis.

Conclusions

The serial changes in the cerebral rSO₂ values during ECPR may predict a patient’s neurological outcome. The further evaluation of the validity of rSO₂ monitoring during ECPR may lead to a new resuscitation strategy.

Load-distributing-band cardiopulmonary resuscitation for out-of-hospital cardiac arrest increases regional cerebral oxygenation: a single-center prospective pilot study

Background

Despite advances in therapeutic strategies and improved guidelines, morbidity and mortality rates for out-of-hospital cardiac arrest (OHCA) remain high. Especially, neurological prognosis is one of the most important problems even though brain protection therapy for patients with OHCA has improved greatly in recent years due to the development of emergency post-cardiac arrest interventions such as mild therapeutic hypothermia, early percutaneous coronary intervention, and extracorporeal cardiopulmonary resuscitation (CPR). Recently, cerebral regional oxygen saturation (rSO₂) has received attention as a method for evaluation of cerebral oxygenation. We have reported that conventional chest compression did not improve the rSO₂ of cardiac arrest patients if they did not achieve return of spontaneous circulation. It is, however, unclear whether a mechanical CPR device is helpful in improving rSO₂. The purpose of this study was to evaluate the effects of load-distributing-band CPR (LDB-CPR) on rSO₂.

Methods

In this prospective study, LDB-CPR was begun for OHCA with the AutoPulse^TM device on patient arrival at hospital. During mechanical CPR, rSO₂ values were recorded continuously from the forehead of the patients. CPR for patients with OHCA was performed according to the Japan Resuscitation Council Guidelines 2010 except for using the AutoPulse^TM instead of manual chest compression.

Results

From December 2012 to December 2013, 34 patients (mean age, 75.6 ± 12.8 years) with OHCA were included in this study. Duration of time from recognition of cardiac collapse to arrival to hospital was 31.0 ± 11.4 min. Compared with the rSO₂ value of 38.9 ± 0.7 % prior to starting LDB-CPR, rSO₂ values at 4, 8 and 12 minutes increased significantly after initiation of LDB-CPR (44.0 ± 0.9 %, 45.2 ± 0.8 %, and 45.5 ± 0.8 %, respectively, p < 0.05).

Conclusion

LDB-CPR significantly increased the rSO₂ of cardiac arrest patients during resuscitation.