Prehospital opioid dose and myocardial injury in patients with ST elevation myocardial infarction.

Abstract

OBJECTIVE:

To characterise the relationship between opioid dose and myocardial infarct size in patients with ST elevation myocardial infarction (STEMI).

METHODS:

Patients given opioid treatment by emergency medical services with confirmed STEMI were included in this secondary, retrospective cohort analysis of the Air versus Oxygen in Myocardial Infarction (AVOID) study. Patients with cardiogenic shock were excluded. The primary endpoint was comparison of cardiac biomarkers as a measure of infarct size based on opioid dose (low ≤8.75 mg, intermediate 8.76-15 mg and high >15 mg of intravenous morphine equivalent dose).

RESULTS:

422 patients were included in the analysis. There was a significantly higher proportion of patients with Thrombolysis in Myocardial Infarction (TIMI) 0 or 1 flow pre-percutaneous coronary intervention (PCI) (94% vs 81%, p=0.005) and greater use of thrombus aspiration catheters (59% vs 30%, p<0.001) in the high compared with low-dose opioid group. After adjustment for potential confounders, every 1 mg of intravenous morphine equivalent dose was associated with a 1.4% (95% CI 0.2%, 2.7%, p=0.028) increase in peak creatine kinase; however, this was no longer significant after adjustment for TIMI flow pre-PCI.

CONCLUSIONS:

Our study suggests no benefit of higher opioid dose and a dose-dependent signal between opioid dose and increased myocardial infarct size. Prospective randomised controlled trials are required to establish causality given that this may also be explained by patients with a greater ischaemic burden requiring higher opioid doses due to more severe pain. Future research also needs to focus on strategies to mitigate the opioid-P2Y12 inhibitor interaction and non-opioid analgesia to treat ischaemic chest pain.

• Authors: Himawan Fernando, Ziad Nehme, Karlheinz Peter, Stephen Bernard, Michael Stephenson, Janet Bray, Peter Cameron, Andris Ellims, Andrew Taylor, David M Kaye, Karen Smith, Dion Stub, AVOID investigators
• Journal: Open heart (Open Heart) Vol. 7 Issue 2 (07 2020) ISSN: 2053-3624 [Print] England
• PMID: 32719075 (Publication Type: Journal Article, Multicenter Study, Observational Study, Research Support, Non-U.S. Gov't)
• Copyright: © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Chemical References

• Analgesics, Opioid
• Biomarkers
• Troponin I
• Creatine Kinase

Topics

• Aged
• Analgesics, Opioid (administration & dosage)
• Biomarkers (blood)
• Creatine Kinase (blood)
• Emergency Medical Services
• Female
• Humans
• Male
• Middle Aged
• Myocardium (metabolism, pathology)
• Percutaneous Coronary Intervention (adverse effects)
• Randomized Controlled Trials as Topic
• Retrospective Studies
• ST Elevation Myocardial Infarction (blood, pathology, therapy)
• Thrombectomy (adverse effects)
• Time Factors
• Treatment Outcome
• Troponin I (blood)
• Victoria