A novel extracorporeal cardiopulmonary resuscitation strategy using a hybrid emergency room for patients with pulseless electrical activity

Novel and innovative resuscitation systems in Japan

Aim

Out-of-hospital cardiac arrest (OHCA) is a life-threatening emergency that requires rapid and efficient intervention. Recently, several novel approaches have emerged and have been incorporated into resuscitation systems in some local areas of Japan. This review describes innovative resuscitation systems and highlights their strengths.

Main text

First, we discuss the deployment of a physician-staffed ambulance, in which emergency physicians offer advanced resuscitation to patients with OHCA on site. In addition, we describe the experimental practice of extracorporeal membrane oxygenation (ECPR) in a prehospital setting. Second, we describe a physician-staffed helicopter, wherein a medical team provides advanced resuscitation at the scene. We also explain their initiative to provide early ECPR, even in remote areas. Finally, we provide an overview of the "hybrid ER" system which is a "one-fits-all" resuscitation bay equipped with computed tomography and fluoroscopy equipment. This system is expected to help swiftly identify and rule out irreversible causes of cardiac arrest, such as massive subarachnoid hemorrhage, and implement ECPR without delay.

Conclusion

Although these revolutionary approaches may improve the outcomes of patients with OHCA, evidence of their effectiveness remains limited. In addition, it is crucial to ensure cost-effectiveness and sustainability. We will continue to work diligently to assess the effectiveness of these systems and focus on the development of cost-effective and sustainable systems.

Venoarterial extracorporeal membrane oxygenation for cardiopulmonary resuscitation: A retrospective study comparing the outcomes of fluoroscopy

Background

Extracorporeal cardiopulmonary resuscitation (ECPR) using venoarterial extracorporeal membrane oxygenation is performed for out-of-hospital cardiac arrest; however, it is associated with a risk of several complications.

Objective

To investigate whether the fluoroscopy equipment was removed from the emergency department (ED) and whether it would be beneficial to transport the patient to the fluoroscopy room to reduce vascular complications without affecting the induction time.

Methods

This single-center, retrospective, before-and-after analysis was conducted at a tertiary emergency medical center and included 59 patients who underwent ECPR for out-of-hospital cardiac arrest between May 2017 and March 2022. The patients were divided into two groups: those who underwent cannulation in the ED without fluoroscopy (ED-ECPR group) and those who were transferred directly from the ED to the cardiac angiography room (ECPR call group).

Results

The rate of vascular complications associated with ECPR was significantly lower in the ECPR group than in the ED-ECPR group (40.6 % [14/32] vs. 10 % [2/20], respectively; p = 0.014). The duration from ED arrival to venoarterial extracorporeal membrane oxygenation initiation was similar in the two groups (median: 23.0 min in the ED-ECPR group vs. 25.5 min in the ECPR call group, p = 0.71). Results adjusted for confounding factors showed that performing ECPR under fluoroscopy was a consistent and independent element of vascular complication rates (adjusted odds ratio: 9.92, 95 % confidence interval: 2.04 to 81.2, p = 0.011).

Conclusions

Fluoroscopy-guided ECPR can significantly reduce the incidence of vascular complications even if the ED and fluoroscopy room are far apart. However, no significant difference was observed in the time required to establish ECPR in the cardiac catheterization laboratories.

Treatment strategy for severe trauma patients requiring aortic occlusion for impending cardiopulmonary arrest in the hybrid emergency room

Aim

Computed tomography (CT) is useful in trauma care. Severely ill trauma patients may not tolerate whole-body CT even without patient transfer. This study examined clinical flow of severe trauma patients requiring aortic occlusion (AO) such as resuscitative thoracotomy or REBOA in the hybrid emergency room (ER) and investigated patient clinical courses prioritizing CT first versus resuscitation including AO first.

Methods

This retrospective, single-center observational study included consecutive trauma patients visiting our ER between May 2016 and February 2023. Patients were divided into the CT first group (whole-body CT preceded AO) and AO first group (AO preceded whole-body CT) and into two subgroups: AO after CT (AO/interventions for hemorrhage performed just after CT in the CT first group), and CT after AO (CT or damage control surgery performed after AO in the AO first group). We investigated 28-day survival rates.

Results

Survival probability by TRISS method was 49% (range: 3.3-94) in the CT first group (n = 6) and 20% (range: 0.7-45) in the AO first group (n = 7). Actual 28-day survival rates were 50% and 57%, respectively. Survival rates of the AO after CT subgroup (CT first group) were 75% (3/4) and 0% (0/2), respectively, and those of the CT after AO subgroup (AO first group) were 25% (1/4) and 100% (3/3), respectively.

Conclusion

In severe trauma patients with low predicted probability of survival treated in the hybrid ER, survival rates might be better if resuscitation including AO is performed before CT and if damage control surgery is performed first before CT.

Effective use of the hybrid emergency Department system in the treatment of non-traumatic critical care diseases

BACKGROUND

The hybrid emergency room (ER) system can provide resuscitation, computed tomography imaging, endovascular treatment, and emergency surgery, without transferring the patient. However, although several reports have demonstrated the effectiveness of the hybrid ER for trauma conditions, only a few case reports have demonstrated its usefulness for non-traumatic critical diseases. In this observational cohort study, we aimed to identify endogenous diseases that may benefit from treatment in the hybrid ER.

METHODS

We retrospectively reviewed the clinical characteristics of patients with non-traumatic conditions treated in a hybrid ER between August 2017 and July 2022 at our institution. Patients who underwent surgery, endoscopy, or interventional radiology (IR) in the hybrid ER were selected and pathophysiologically divided into a bleeding and non-bleeding group. The rate of shock or cardiac arrest, blood transfusion, and death within 24 h of admission or in-hospital death were compared among the groups using Fisher's exact test. Multivariable logistic regression analysis was performed to confirm the relationships among in-hospital mortality, transfusion, and hemorrhagic conditions in patients who underwent endoscopy and IR.

RESULTS

Among the 726 patients with non-traumatic conditions treated in a hybrid ER system, 50 (6.9%) experienced cardiac arrest at or before admission to the hybrid ER, 301 (41.5%) were in shock, 126 (17.4%) received blood transfusions, 42 (5.8%) died within 24 h of admission to the hybrid ER, and 141 (19.4%) died in the hospital. Emergency surgery was performed in 39 patients (7 in the bleeding group and 32 in the non-bleeding group). Significantly more blood transfusions were administered in the bleeding group (71.4% vs. 18.8%, P = 0.01); there were no significant differences in the rate of shock or cardiac arrest, death within 24 h, or in-hospital death between groups. Endoscopy was performed in 122 patients (80 in the bleeding group and 42 in the non-bleeding group). The bleeding group had a significantly higher rate of shock or cardiac arrest (87.5% vs. 66.7%, P = 0.008) and rate of blood transfusion (62.5% vs. 4.8%, P < 0.0001); there was no significant difference in death within 24 h and in-hospital death between groups. IR was performed in 100 patients (68 in the bleeding group and 32 in the non-bleeding group). Significantly more blood transfusions were administered in the hemorrhage group (67.7% vs. 12.5%, P < 0.0001); there was no difference in the rate of shock or cardiac arrest, death within 24 h, or in-hospital death between groups. Multivariable analysis in patients who underwent endoscopy showed a trend toward more in-hospital deaths in non-hemorrhagic conditions than in hemorrhagic conditions (odds ratio = 3.8, 95% confidence interval: 0.88-17, P = 0.073); however, no significant relationship with in-hospital death was observed for any of the adjusted variables.

CONCLUSION

Among endogenous diseases treated in the hybrid ER, there is a possible association between in-hospital mortality and hemorrhagic conditions. Future studies are needed to focus on diseases to demonstrate the effectiveness of the hybrid ER.

Application of the TiPS65 score for out-of-hospital cardiac arrest patients with initial non-shockable rhythm treated with ECPR

Background

The TiPS65 score is a validated scoring system used to predict neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients with shockable rhythm treated with extracorporeal cardiopulmonary resuscitation (ECPR). This study aimed to assess the predictive performance of the TiPS65 score in OHCA patients with initial non-shockable rhythm treated with ECPR.

Methods

This was a secondary analysis using the JAAM-OHCA registry, a multicenter prospective cohort study. The study included adult OHCA patients with initial non-shockable rhythm who underwent ECPR. The TiPS65 score assigned one point to each of four variables: time to hospital ≤25 minutes, pH value ≥7.0 on initial blood gas assessment, shockable on hospital arrival, and age younger than 65 years. Based on the sum score, the predictive performance for 1-month survival and favorable neurological outcomes, defined as the Cerebral Performance Category 1 or 2, was evaluated.

Results

Among 57,754 patients in the registry, 370 were included in the analysis. The overall one-month survival and favorable neurological outcome were 11.1% (41/370) and 4.2% (15/370), respectively. The 1-month survival rates based on the TiPS65 score were as follows: 11.2% (12/107) for 0 points, 9.3% (14/150) for 1 point, 10.0% (9/90) for 2 points, and 26.1% (6/23) for ≥3 points. Similarly, the 1-month favorable neurological outcomes were: 5.6% (6/107) for 0 points, 2.7% (4/150) for 1 point, 4.4% (4/90) for 2 points, and 4.3% (1/23) for ≥3 points. The area under the curve was 0.535 (95% CI: 0.437-0.630) for 1-month survival and 0.530 (95% CI: 0.372-0.683) for 1-month neurological outcome.

Conclusion

This study demonstrates that the TiPS65 score has limited prognostic performance among OHCA patients with initial non-shockable rhythm treated with ECPR. Further research is warranted to develop a predictive tool specifically focused on OHCA with initial non-shockable rhythm to aid in determining candidates for ECPR.

Impact of the hybrid emergency department on resuscitation strategies and outcomes in ventricular fibrillation

BACKGROUND

The Hybrid emergency room (ER) is a novel resuscitation room that includes a whole-body computed tomography scanner and angiography system, which enables physicians to seamlessly conduct resuscitation, diagnosis and therapeutic interventions without patient transfer. This study aimed to assess the impact of the Hybrid ER on mortality in patients with ventricular fibrillation cardiac arrest.

METHODS

This was a retrospective cohort study conducted in a tertiary hospital in Japan. We consecutively included adult cardiac arrest patients who were transferred to the emergency departments from January 2007 to May 2020, and were confirmed to be in ventricular fibrillation within 10 min from patient arrival. The study population was divided into two groups: the conventional group (from January 2007 to July 2011) and the Hybrid ER group (from August 2011 to May 2020). The primary endpoint of this study was defined as all-cause in-hospital death. Secondary endpoints included the frequency of extracorporeal cardiopulmonary resuscitation (ECPR) and percutaneous coronary intervention (PCI), and door-to-balloon time and door-to-ECPR time.

RESULTS

We included 115 patients in the conventional group and 185 patients in the Hybrid ER group. In-hospital mortality was significantly decreased in the Hybrid ER group (adjusted hazard ratio, 0.79; 95% confidence interval 0.64, 0.97; p = 0.026). Door-to-ECPR time was significantly shorter in the Hybrid ER group (p < 0.001, Gehan-Breslow-Wilcoxon test), as was door-to-balloon time in this group (p = 0.004, Gehan-Breslow-Wilcoxon test). In interrupted time-series analyses, it was visually recognized that the ratio of patients who received ECPR and PCI increased, and door-to-ECPR time and door-to-balloon time were shortened from 2011 to 2012 (before and after installation of the Hybrid ER).

CONCLUSION

Installation of the Hybrid ER was associated with a reduced time to ECPR and PCI and with a possible improvement in survival in patients with ventricular fibrillation cardiac arrest.

Neurological outcomes and reperfusion strategies in out-of-hospital cardiac arrest patients due to pulmonary embolism who underwent venoarterial extracorporeal membrane oxygenation: A post-hoc analysis of a multicenter retrospective cohort study

INTRODUCTION

This study aimed to evaluate the effect of different reperfusion strategies on neurological outcomes in patients with pulmonary embolism who received venoarterial extracorporeal membrane oxygenation (VA-ECMO) for out-of-hospital cardiac arrest (OHCA).

METHODS

This was a post-hoc analysis of a multicenter retrospective cohort study conducted in 36 institutions in Japan over six years. We included patients who underwent VA-ECMO and were diagnosed with pulmonary embolism caused by OHCA. Neurological outcomes were evaluated on the basis of the cerebral performance category at hospital discharge. We also assessed the association between reperfusion strategies and successful separation from ECMO.

RESULTS

Among the 78 included patients, approximately half were successfully weaned from ECMO. Hospital mortality and favorable neurological outcomes at hospital discharge were 60.3% and 17.9%, respectively. Thirty-one patients (39.7%) underwent reperfusion strategies after ECMO, including 13 who received systemic thrombolytic therapy and 18 who underwent mechanical reperfusion strategy. After adjusting for prespecified covariates using the competing risk model, reperfusion strategies increased ECMO separation rate (systemic thrombolytic therapy: subdistribution hazard ratio [sHR] 2.24, 95% confidence interval [CI] 1.21-4.17, P = 0.011; mechanical reperfusion strategy: sHR 1.70, 95% CI 0.86-3.41, P = 0.129) compared with anticoagulation therapy alone, whereas higher cardiac Sequential Organ Failure Assessment score decreased ECMO separation rate (sHR 0.81, 95% CI 0.67-0.97, P = 0.020).

CONCLUSIONS

Favorable neurological outcomes were observed in less than 20% of patients with OHCA due to pulmonary embolism undergoing ECMO. Reperfusion strategies may be associated with shorter ECMO durations in these patients.

CLINICAL TRIAL REGISTRATION

https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000041577 (unique identifier: UMIN000036490).

Clinical characteristics and outcomes after extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients with an initial asystole rhythm

AIM

This study aimed to describe the characteristics of cases of out-of-hospital cardiac arrest (OHCA) with an initial asystole rhythm in which extracorporeal cardiopulmonary resuscitation (ECPR) was introduced and discuss the clinical indications for ECPR in such patients.

METHODS

This was a secondary analysis of the SAVE-J II study, a retrospective, multicentre, registry study involving 36 participating institutions in Japan. Patients with an initial asystole rhythm were selected. Favourable neurological outcomes (cerebral performance categories 1-2) constituted the primary outcome.

RESULTS

In total, 202 patients met the inclusion criteria, with favourable neurological outcomes at hospital discharge in 12 patients (5.9%). Causes of cardiac arrest with favourable neurological outcomes were hypothermia (7 cases), acute coronary syndrome (2 cases), arrhythmia (2 cases), and pulmonary embolism (1 case). Among patients with non-hypothermia (temperature ≥32 °C) on hospital arrival with the cardiac rhythm of asystole or pulseless electrical activity (PEA) on arrival, all 107 patients (66 asystole, 41 PEA) who lacked one or more of the requirements (witness; bystander CPR; signs of life or pupil < 5 mm) had unfavourable neurological outcomes. All 5 cases with favourable neurological outcomes, except for 1 case with a short duration of no-flow time that was highly suspected based on the patient's history, met all the requirements on hospital arrival.

CONCLUSIONS

A total of 202 ECPR cases with an initial asystole rhythm, including 12 patients with favourable neurological outcomes, were described. Even if the initial cardiac rhythm is asystole, ECPR could be considered if certain conditions are met.