Adverse events after prehospital nitroglycerin administration in a nationwide registry analysis

• Published in: The American journal of emergency medicine 2021-12, Vol.50, p.196-201
• Main Authors: Popp, Lucas M., Lowell, Luke M., Ashburn, Nicklaus P., Stopyra, Jason P.
• Format: Article
• Language: English
• Subjects: Adverse events; Adverse reaction; Age; Aged; Blood pressure; Bradycardia; Cardiac arrhythmia; Chest pain; Collaboration; Demographics; Demography; Electronic health records; Emergency medical care; Emergency Medical Services; Emergency medical services (EMS); Ethnicity; Female; Heart rate; Humans; Hypotension; Hypotension - chemically induced; Intravenous administration; Male; Middle Aged; Minority & ethnic groups; Nitroglycerin; Nitroglycerin - administration & dosage; Nitroglycerin - adverse effects; Pain; Patients; Population; Registries; Regression analysis; Risk Factors; Statistical analysis; Tachycardia; Vasodilator Agents - administration & dosage; Vasodilator Agents - adverse effects
• ISSN: 0735-6757; 1532-8171; 1532-8171
• DOI: 10.1016/j.ajem.2021.08.006

Nitroglycerin (NTG) is a vasodilator used in the prehospital setting with chest pain patients. Potential adverse effects include hypotension, bradycardia or tachycardia, and mental status change. However, it is unclear which factors, if any, are associated with patients having an adverse event after receiving NTG. The objective of this study was to determine demographic and clinical factors associated with adverse events after prehospital NTG administration. The ESO Data Collaborative (Austin, TX), containing records from 1322 EMS agencies, was queried for 911 encounters where NTG was administered to patients ≥18 years old by EMS. Adverse event outcomes were defined as a new systolic blood pressure (SBP) < 90, heart rate (HR) < 50 or > 120, mean arterial pressure (MAP) < 65, or change in mental status following NTG administration. Descriptive statistics and logistic regression models adjusting for age, sex, race, ethnicity, intravenous (IV) access, and initial vital signs were used to assess for adverse event-related factors. Among 80,760 encounters, the mean age was 61 (IQR 50–72), with 52% males, 71% white race, and 7% Hispanic ethnicity. Adverse events occurred in 7% of encounters. Adverse events were found to be less common among Black patients (OR = 0.74, 95%CI:0.69–0.80). IV access obtained prior to NTG administration was associated with fewer adverse events (OR = 0.92, 95%CI:0.85–0.99). Increasing age (OR = 1.02, 95%CI:1.01–1.02) and HR (OR = 1.03, 95%CI:1.02–1.03) were associated with increased odds of adverse events while SBP (OR = 0.99, 95%CI:0.98–0.99) was inversely associated. Adverse events following prehospital NTG administration were rare, especially in patients with an SBP > 110 and a HR < 100, and less frequent in those with existing IV access. Demographics were not found to be clinically significant. •Hypotension following nitroglycerin administration was rare at 2%.•Demographics should not deter EMS personnel from administering nitroglycerin.•Intravenous access should be established prior to nitroglycerin administration.