Out-of-hospital cardiac arrest: Causes according to autopsy and electrocardiography - Analysis of 781 patients with neither hospital care nor prescribed medication during the preceding two years

Pulmonary vasodilation during cardiopulmonary resuscitation - a randomized, controlled porcine study

BACKGROUND

During resuscitation pulmonary artery pressure (PAP) increases. This reduces left ventricular filling, leading to decreased blood flow. Inhaled nitric oxide (iNO) produces selective pulmonary vasodilation. We hypothesized that iNO would lower PAP during resuscitation resulting in increased survival.

METHODS

30 pigs (40kg) were subjected to cardiac arrest for 9.5 minutes after myocardial ischemia induced by coronary artery occlusion of the left anterior descending artery and ventricular fibrillation. During resuscitation, the pigs were randomized to 40 ppm iNO or placebo. The primary outcome was return of spontaneous circulation (ROSC). Pigs achieving ROSC underwent 4-hours intensive care.

RESULTS

The ROSC rate was 9/14 (64%) in the control group and 11/16 (69%) in the iNO group (OR 1.2 95%CI [0.3;5.6], p>0.99). There was no difference in diastolic aorta pressure/PAP ratio (mean difference -0.99 [95% CI: -2.33-0.36], p=0.14). Mean pulmonary artery pressure was lower in the iNO group 60 and 120 minutes after ROSC (mean difference: -12.18 mmHg [95%CI: -16.94; -7.43] p<0.01 and -5.43 [95%CI: -10.39; -0.46] p=0.03). Troponin I levels in the iNO group were significantly higher 60 and 120 minutes after ROSC (mean difference: 266105 ng/l [95%CI: 6356; 525855] p=0.045 and 420049 ng/l [95%CI: 136779; 703320], p=0.004). The area at risk of the heart was 33% (SD 1) in controls and 34% (SD 1) in the iNO group. The infarct size divided by the area at risk was 55% (SD 3) in controls and 86% (SD 1) in the iNO group, p=0.01.

CONCLUSION

Application of iNO did not improve the rate of ROSC or hemodynamic function but increased myocardial injury.

High-sensitivity troponin T for detection of culprit lesions in patients with out-of-hospital cardiac arrest

BACKGROUND

Patients with an out-of-hospital cardiac arrest (OHCA) often undergo coronary angiography, although a culprit lesion is found in only 30%-40% of patients. The aim of this study was to investigate high-sensitivity troponin T (hsTnT) levels in post cardiac arrest patients with and without coronary culprit lesions; factors affecting hsTnT levels after return of spontaneous circulation (ROSC); and the diagnostic ability of hsTnT in identifying patients with culprit lesions. We hypothesized that peak hsTnT levels were higher during the initial 48 h after cardiac arrest in patients with a coronary culprit lesion.

METHODS

This was a retrospective observational study, which included patients admitted to the Intensive Care Unit after an OHCA and who received a coronary angiography. Peak values and dynamic changes in hsTnT were analyzed in relation to the presence of a culprit lesion at coronary angiography.

RESULTS

A total of 238 patients were studied, of whom 140 had a culprit lesion. HsTnT levels during the initial 48 h were higher in patients with culprit lesions, longer time to ROSC and an unwitnessed cardiac arrest. At 6 to 12 h after ROSC, a hsTnT cut-off level of 1690 ng/L had a sensitivity of 64% and specificity of 84% to identify a culprit lesion. In patients without ST-elevations, hsTnT measured between 6 and 12 h after ROSC had a specificity above 90%, with a sensitivity of 46%.

CONCLUSION

HsTnT levels after cardiac arrest are higher in patients with coronary culprit lesions. Presence of a culprit lesion, witnessed status and the duration of CPR are important factors affecting hsTnT levels. Repeated measurement of hsTnT within the first 12 h after admission improved diagnostic accuracy but the value of hsTnT as a predictor of culprit lesions early after OHCA is limited.

Cardiac Arrest in Pigs With 48 hours of Post-Resuscitation Care Induced by 2 Methods of Myocardial Infarction: A Methodological Description

Background

Systematic reviews have disclosed a lack of clinically relevant cardiac arrest animal models. The aim of this study was to develop a cardiac arrest model in pigs encompassing relevant cardiac arrest characteristics and clinically relevant post‐resuscitation care.

Methods and Results

We used 2 methods of myocardial infarction in conjunction with cardiac arrest. One group (n=7) had a continuous coronary occlusion, while another group (n=11) underwent balloon‐deflation during arrest and resuscitation with re‐inflation after return of spontaneous circulation. A sham group was included (n=6). All groups underwent 48 hours of intensive care including 24 hours of targeted temperature management. Pigs underwent invasive hemodynamic monitoring. Left ventricular function was assessed by pressure‐volume measurements. The proportion of pigs with return of spontaneous circulation was 43% in the continuous infarction group and 64% in the deflation‐reinflation group. In the continuous infarction group 29% survived the entire protocol while 55% survived in the deflation‐reinflation group. Both cardiac arrest groups needed vasopressor and inotropic support and pressure‐volume measurements showed cardiac dysfunction. During rewarming, systemic vascular resistance decreased in both cardiac arrest groups. Median [25%;75%] troponin‐I 48 hours after return of spontaneous circulation, was 88 973 ng/L [53 124;99 740] in the continuous infarction group, 19 661 ng/L [10 871;23 209] in the deflation‐reinflation group, and 1973 ng/L [1117;1995] in the sham group.

Conclusions

This article describes a cardiac arrest pig model with myocardial infarction, targeted temperature management, and clinically relevant post‐cardiac arrest care. We demonstrate 2 methods of inducing myocardial ischemia with cardiac arrest resulting in post‐cardiac arrest organ injury including cardiac dysfunction and cerebral injury.

Study of pre-hospital care of out of hospital cardiac arrest victims and their outcome in a tertiary care hospital in India

Background

India does not have a formal cardiac arrest registry or a centralized emergency medical system. In this study, we aimed to assess the prehospital care received by the patients with OHCA and predict the factors that could influence their outcome.

Methods

Out-of-hospital cardiac arrest patients presenting to the emergency department in a tertiary care centre were included in the study. Prehospital care was assessed in terms of bystander cardiopulmonary resuscitation (CPR), mode of transport, resuscitation in ambulance. OHCA outcomes like Return of spontaneous circulation (ROSC), survival to hospital discharge and favourable neurological outcome at discharge were assessed.

Results

Among 205 patients, the majority were male (71.2%) and were above 60 years of age (49.3%); Predominantly non-traumatic (82.4%). 30.7% of the patients had sustained cardiac arrest in transit to the hospital. 41.5% of patients reached hospital by means other than ambulance. Only 9.8% patients had received bystander CPR. Only 12.5% ambulances had BLS trained personnel. AED was used only in 1% of patients. The initial rhythm at presentation to the hospital was non-shockable (96.5%). Return of spontaneous circulation (ROSC) was achieved in 17 (8.3%) patients, of which only 3 (1.4%) patients survived till discharge. The initial shockable rhythm was a significant predictor of ROSC (OR 18.97 95%CI 3.83–93.89; p < 0.001) and survival to discharge (OR 42.67; 95%CI 7.69–234.32; p < 0.001).

Conclusion

The outcome of OHCA in India is dismal. The pre-hospital care received by the OHCA victim needs attention. Low by-stander CPR rate, under-utilised and under-equipped EMS system are the challenges.

Importance of Immediate Electronic-Based Feedback to Enhance Feedback for First-Time CPR Trainees

Sudden cardiac arrest is one of the leading causes of death globally. The recommended clinical management in out-of-hospital cardiac arrest cases is the immediate initiation of high-quality cardiopulmonary resuscitation (CPR). Training mannequins should be combined with technology that provides students with detailed immediate feedback on the quality of CPR performance. This study aimed to verify the impacts of the type of feedback (basic or detailed) the responders receive from the device while learning CPR and how it influences the quality of their performance and the motivation to improve their skills. The study was conducted at the Medical University of Lublin among 694 multi-professional health students during first aid classes on basic life support (BLS). The students first practiced on an adult mannequin with a basic control panel; afterward, the same mannequin was connected to a laptop, ensuring a detailed record of the performed activities through a projector. Next, the participants expressed their subjective opinion on how the feedback provided during the classes, basic vs. detailed, motivated them to improve the quality of their CPR performance. Additionally, during the classes, the instructor conducted an extended observation of students’ work and behavior. In the students’ opinion, the CPR training with detailed feedback devices provided motivation for learning and improving CPR proficiency than that with a basic control panel. Furthermore, the comments given from devices seemed to be more acceptable to the students, who did not see any bias in the device’s evaluation compared to that of the instructor. Detailed device feedback motivates student health practitioners to learn and improve the overall quality of CPR. The use of mannequins that provide detailed feedback during BLS courses can improve survival in out-of-hospital cardiac arrest.