Neurological Injury and Outcomes in Fentanyl-related Cardiac Arrest

Area of Science:

• Emergency Medicine
• Neurology
• Toxicology

Background:

• Fentanyl is a leading cause of fatal overdoses in US urban areas.
• Limited data exists on neurological outcomes following fentanyl-related cardiac arrest (CA) compared to other causes.
• Understanding these outcomes is crucial for public health and clinical management.

Purpose of the Study:

• To compare neurological outcomes in patients experiencing out-of-hospital CA due to fentanyl overdose versus other etiologies.
• To identify specific neurological injury patterns associated with fentanyl-related CA.
• To evaluate the impact of fentanyl on resuscitation efforts and post-CA neurological status.

Main Methods:

• Retrospective review of adult patients with out-of-hospital CA and drug testing for fentanyl/opioids (August 2019-June 2021).
• Defined good neurological outcome as Cerebral Performance Category (CPC) score of 1-2 at discharge.
• Used chi-squared (χ2) tests for group comparisons.

Main Results:

• Of 233 patients, 61 (26.2%) had good outcomes. Fentanyl-positive cases (15.45%) showed fewer bystander CPR (19.4%) and shockable rhythms (2.9%) compared to other opioid (38.5%, 16.7%) and non-opioid (43.8%, 25%) groups.
• Fentanyl-related CA had higher rates of severe brain dysfunction on electroencephalography (EEG) burst suppression (54.8%) versus other groups (0-39.4%).
• Despite neurological injury indicators, the proportion of good neurological outcomes (CPC 1-2) was similar across fentanyl (22.2%), other opioid (38.5%), and non-opioid (26.1%) groups (P=0.52).

Conclusions:

• Fentanyl-associated cardiac arrest is linked to reduced bystander CPR and increased non-shockable rhythms.
• EEG findings suggest greater neurological injury in fentanyl-related CA cases.
• The overall rate of good neurological outcomes remains comparable across different CA etiologies, despite varying initial resuscitation factors and injury patterns.