Goal-directed cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest in the emergency Department: A feasibility study

Implementation of advanced vascular access, physiological monitoring and goal-directed resuscitation during OHCA in a helicopter emergency medical service

Outcomes after out-of-hospital cardiac arrest (OHCA) remain poor in the UK. In order to increase the chances of successful resuscitation, international society guidelines on cardiopulmonary resuscitation quality have recommended titration of chest compression parameters and vasopressor administration to arterial diastolic blood pressure if invasive catheters are in situ at the time of cardiac arrest. However, prehospital initiation of arterial and central venous catheterisation is seldom undertaken due to the risks and significant technical challenges in the context of ongoing resuscitation in this environment. In 2019, a dedicated programme was started at East Anglian Air Ambulance (EAAA) to enable the safe introduction of contemporary emergency vascular access devices, in order to improve physiological monitoring intra-arrest and deliver nuanced, goal-directed resuscitation in OHCA patients. This programme was entitled Specialist Percutaneous Emergency Aortic Resuscitation (SPEAR). This article details the EAAA SPEAR technique; and the development, implementation and governance of this novel endovascular strategy in our UK physician-paramedic staffed helicopter emergency medical service.

Emergency medicine updates: Cardiopulmonary resuscitation

INTRODUCTION

Cardiac arrest is the loss of functional cardiac activity; emergency clinicians are integral in the management of this condition.

OBJECTIVE

This paper evaluates key evidence-based updates concerning cardiopulmonary resuscitation (CPR).

DISCUSSION

Cardiac arrest includes shockable rhythms (i.e., pulseless ventricular tachycardia and ventricular fibrillation) and non-shockable rhythms (i.e., asystole and pulseless electrical activity). The goal of cardiac arrest management is to achieve survival with a good neurologic outcome, in part by restoring systemic perfusion and obtaining return of spontaneous circulation (ROSC), while seeking to diagnose and treat the underlying etiology of the arrest. CPR includes high-quality chest compressions to optimize coronary and cerebral perfusion pressure. Chest compressions should be centered over the mid-sternum, with the compressor's body weight over the middle of the chest. A compression depth of 5-6 cm is recommended at a rate of 100-120 compressions per minute, while allowing the chest to fully recoil between each compression. Clinicians should seek to minimize any interruptions in compressions. When performed by bystanders, compression-only CPR may be associated with improved survival to hospital discharge when compared to conventional CPR with ventilations. However, in trained personnel, there is likely no difference with compression-only versus conventional CPR. Mechanical approaches for CPR are not associated with improved patient outcomes, including ROSC or survival with good neurologic function, but mechanical compression devices may be beneficial in select circumstances (e.g., few rescuers available, prolonged arrest/transport). Monitoring of chest compressions is not associated with improved ROSC, survival, or neurologic outcomes, but it can improve guideline adherence. Types of monitoring include real-time feedback, a CPR coach, end tidal CO2, arterial line monitoring, regional cerebral tissue oxygenation, and point-of-care ultrasound.

CONCLUSIONS

An understanding of CPR literature updates can improve the ED care of patients in cardiac arrest.

Contextualizing Pseudo-Pulseless Electrical Activity in Cardiac Arrest: A Meta-Analysis and Systematic Review

OBJECTIVE

Nonshockable cardiac arrest rhythms have demonstrably poor outcomes. Pseudo-pulseless electrical activity (PEA), a subset of PEA in which visible cardiac contractility is present, is being described more frequently in recent literature. Physiology suggests that presence of cardiac motion even without a palpable pulse is energetically more favorable than true PEA, which is more like asystole. Therefore, we hypothesize that there is an increase in the survivability of PEA compared with asystole which may in part be due to a subset of pseudo-PEA.

METHODS

A PICOST research question was generated which guided the composition of a systematic review and meta-analysis in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist.

RESULTS

A total of 494,355 patients were identified from 12 pieces of literature. Meta-analyses revealed an overall increased survivability of PEA compared with asystole (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.52-2.86). When differentiating between location of arrest, PEA was more survivable in both in-hospital cardiac arrest and out-of-hospital cardiac arrest than asystole (out-of-hospital cardiac arrest OR 4.17, 95% CI 3.78-4.60, and in-hospital cardiac arrest OR 1.60, 95% CI 1.42-1.79). Finally, when comparing neurological outcome of PEA with asystole, PEA was more favorable (OR 3.32, 95% CI 1.39-7.94).

CONCLUSION

Pseudo-PEA may be one of the explanations attributed to better outcomes of PEA, especially neurological, due to the presence of cerebral and coronary flow. The presence of PEA likely requires evidence-based tailored management with presence of pseudo-PEA being more like a profound shock state. More evidence is required to investigate the true incidence of pseudo-PEA and its outcomes compared with true PEA.

The association between intra-arrest arterial blood pressure and return of spontaneous circulation in out-of-hospital cardiac arrest

BACKGROUND

The optimal haemodynamic parameter for goal-directed resuscitation in out-of-hospital cardiac arrest (OHCA) remains uncertain. This study aimed to characterise the association between invasive blood pressure (IBP) measurements and return of spontaneous circulation (ROSC) in adult OHCA patients, to identify this parameter.

METHODS

A retrospective observational study was conducted at East Anglian Air Ambulance (EAAA). Adult (≥18 years) medical OHCA patients attended by EAAA between 01/02/2015 and 01/02/2024, who had arterial IBP measurement during chest compressions were included. The initial, minimum, maximum, average (mean) and Δ (maximum-initial) were calculated for systolic (SBP), diastolic (DBP) and mean arterial (MAP) components of IBP. Logistic regression and receiver operating characteristic curves tested the association between IBP variables and ROSC.

RESULTS

During the study period, 4363 OHCA patients were attended and 80 met inclusion criteria. Thirty-four patients (42.5 %) achieved ROSC and 4 (5.0 %) survived to discharge. The maximum, average and Δ DBP; and maximum and average MAP were positively associated with ROSC. Maximum DBP had an AUC of 0.83 (95 % CI 0.74-0.92) with an optimal cut-off of 35 mmHg (sensitivity 94.1 %; specificity 58.7 %) for predicting ROSC. The odds ratio for ROSC was 1.05 (95 % CI 1.03-1.08) for every 1 mmHg increase in maximum DBP.

CONCLUSIONS

This study supports the use of arterial DBP as an important haemodynamic parameter for goal-directed resuscitation in adult OHCA. Maximising DBP may increase the chances of ROSC. These data suggest that a DBP threshold of 35 mmHg is optimal for identifying patients who may achieve ROSC with continued resuscitation.

2024 RECOVER Guidelines: Monitoring. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR

OBJECTIVE

To systematically review evidence on and devise treatment recommendations for patient monitoring before, during, and following CPR in dogs and cats, and to identify critical knowledge gaps.

DESIGN

Standardized, systematic evaluation of literature pertinent to peri-CPR monitoring following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by Evidence Evaluators, and findings were reconciled by Monitoring Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk:benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization.

SETTING

Transdisciplinary, international collaboration in university, specialty, and emergency practice.

RESULTS

Thirteen questions pertaining to hemodynamic, respiratory, and metabolic monitoring practices for identification of cardiopulmonary arrest, quality of CPR, and postcardiac arrest care were examined, and 24 treatment recommendations were formulated. Of these, 5 recommendations pertained to aspects of end-tidal CO2 (ETco2) measurement. The recommendations were founded predominantly on very low quality of evidence, with some based on expert opinion.

CONCLUSIONS

The Monitoring Domain authors continue to support initiation of chest compressions without pulse palpation. We recommend multimodal monitoring of patients at risk of cardiopulmonary arrest, at risk of re-arrest, or under general anesthesia. This report highlights the utility of ETco2 monitoring to verify correct intubation, identify return of spontaneous circulation, evaluate quality of CPR, and guide basic life support measures. Treatment recommendations further suggest intra-arrest evaluation of electrolytes (ie, potassium and calcium), as these may inform outcome-relevant interventions.

Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) and ultrasound-guided left stellate ganglion block to rescue out of hospital cardiac arrest due to refractory ventricular fibrillation: A case report

Out of hospital cardiac arrest from shockable rhythms that is refractory to standard treatment is a unique challenge. Such patients can achieve neurological recovery even with long low-flow times if perfusion can somehow be restored to the heart and brain. Extracorporeal cardiopulmonary resuscitation is an effective treatment for refractory cardiac arrest if applied early and accurately, but often cannot be directly implemented by frontline providers and has strict inclusion/exclusion criteria. We present the case of a novel treatment strategy for out of hospital cardiac arrest due to refractory ventricular fibrillation utilizing Resuscitative Endovascular Balloon Occlusion of the Aorta-assisted cardiopulmonary resuscitation and intra-arrest left stellate ganglion blockade to achieve return of spontaneous circulation and eventual good neurological outcome after 101 minutes of downtime.

Resuscitation Strategies for Maximizing Survival

There is no single resuscitation strategy that will uniformly improve cardiac arrest outcomes. Traditional vital signs cannot be relied on in cardiac arrest, and the use of continuous capnography, regional cerebral tissue oxygenation, and continuous arterial monitoring are options for use early defibrillation are critical elements of resuscitation. Cardio-cerebral perfusion may be improved with the use of active compression-decompression CPR, an impedance threshold device, and head-up CPR. In refractory shockable arrest, if ECPR is not an option, consider changing defibrillator pad placement and/or double defibrillation, additional medication options, and possibly stellate ganglion block.

Using point-of-care testing for adult patients with out-of-hospital cardiac arrest resuscitated at the emergency department to predict return of spontaneous circulation: Development and external validation of POC-ED-ROSC model

BACKGROUND AND IMPORTANCE

Most prediction models, like return of spontaneous circulation (ROSC) after cardiac arrest (RACA) or Utstein-based (UB)-ROSC score, were developed for prehospital settings to predict the probability of ROSC in patients with out-of-hospital cardiac arrest (OHCA). A prediction model has been lacking for the probability of ROSC in patients with OHCA at emergency departments (EDs).

OBJECTIVE

In the present study, a point-of-care (POC) testing-based model, POC-ED-ROSC, was developed and validated for predicting ROSC of OHCA at EDs.

DESIGN, SETTINGS AND PARTICIPANTS

Prospectively collected data for adult OHCA patients between 2015 and 2020 were analysed. POC blood gas analysis obtained within 5 min of ED arrival was used.

OUTCOMES MEASURE AND ANALYSIS

The primary outcome was ROSC. In the derivation cohort, multivariable logistic regression was used to develop the POC-ED-ROSC model. In the temporally split validation cohort, the discriminative performance of the POC-ED-ROSC model was assessed using the area under the receiver operating characteristic (ROC) curve (AUC) and compared with RACA or UB-ROSC score using DeLong test.

MAIN RESULTS

The study included 606 and 270 patients in the derivation and validation cohorts, respectively. In the total cohort, 471 patients achieved ROSC. Age, initial cardiac rhythm at ED, pre-hospital resuscitation duration, and POC testing-measured blood levels of lactate, potassium and glucose were significant predictors included in the POC-ED-ROSC model. The model was validated with fair discriminative performance (AUC: 0.75, 95% confidence interval [CI]: 0.69-0.81) with no significant differences from RACA (AUC: 0.68, 95% CI: 0.62-0.74) or UB-ROSC score (AUC: 0.74, 95% CI: 0.68-0.79).

CONCLUSION

Using only six easily accessible variables, the POC-ED-ROSC model can predict ROSC for OHCA resuscitated at ED with fair accuracy.

Advanced and Invasive Cardiopulmonary Resuscitation (CPR) Techniques as an Adjunct to Advanced Cardiac Life Support

BACKGROUND

Despite numerous promising innovations, the chance of survival from sudden cardiac arrest has remained virtually unchanged for decades. Recently, technological advances have been made, user-friendly portable devices have been developed, and advanced invasive procedures have been described that could improve this unsatisfactory situation.

METHODS

A selective literature search in the core databases with a focus on randomized controlled trials and guidelines.

RESULTS

Technical aids, such as feedback systems or automated mechanical cardiopulmonary resuscitation (CPR) devices, can improve chest compression quality. The latter, as well as extracorporeal CPR, might serve as a bridge to treatment (with extracorporeal CPR even as a bridge to recovery). Sonography may be used to improve thoracic compressions on the one hand and to rule out potentially reversible causes of cardiac arrest on the other. Resuscitative endovascular balloon occlusion of the aorta might enhance myocardial and cerebral perfusion. Minithoracostomy, pericardiocentesis, or clamshell thoracotomy might resolve reversible causes of cardiac arrest.

CONCLUSIONS

It is crucial to identify those patients who may benefit from an advanced or invasive procedure and make the decision to implement the intervention in a timely manner. As with all infrequently performed procedures, sound education and regular training are paramount.

Resuscitative endovascular occlusion of the aorta (REBOA) as a mechanical method for increasing the coronary perfusion pressure in non-traumatic out-of-hospital cardiac arrest patients

AIM

of the study Resuscitative endovascular balloon occlusion of the aorta (REBOA), originally designed to block blood flow to the distal part of the aorta by placing a balloon in trauma patients, has recently been shown to increase coronary perfusion in cardiac arrest patients. This study evaluated the effect of REBOA on aortic pressure and coronary perfusion pressure (CPP) in non-traumatic out of-hospital cardiac arrest (OHCA) patients.

METHODS

Adult OHCA patients with cerebral performance category 1 or 2 prior to cardiac arrest, and without evidence of aortic disease, were enrolled from January to December 2021. Aortic pressure and right atrial pressure were measured before and after balloon occlusion. The CPP was calculated using the measured aortic and right atrial pressures, and the values before and after the balloon occlusion were compared.

RESULTS

Fifteen non-traumatic OHCA patients were enrolled in the study. The median call to balloon time was 46.0 (IQR, 38.0-54.5) min. The median CPP before and after balloon occlusion was 13.5 (IQR, 5.8-25.0) and 25.2 (IQR, 12.0-44.6) mmHg, respectively (P = 0.001). The median increase in the estimated CPP after balloon occlusion was 86.7%.

CONCLUSIONS

The results of this study suggest that REBOA may increase the CPP during cardiopulmonary resuscitation in patients with non-traumatic OHCA. Additional studies are needed to investigate the effect on clinical outcomes.