Elsevier

American Heart Journal

Volume 163, Issue 3, March 2012, Pages 339-345.e1
American Heart Journal

Trial Design
A randomized controlled trial of oxygen therapy in acute myocardial infarction Air Verses Oxygen In myocarDial infarction study (AVOID Study)

https://doi.org/10.1016/j.ahj.2011.11.011Get rights and content

Background

The role of routine supplemental oxygen for patients with uncomplicated acute myocardial infarction (AMI) has recently been questioned. There is conflicting data on the possible effects of hyperoxia on ischemic myocardium. The few clinical trials examining the role of oxygen in AMI were performed prior to the modern approach of emergent reperfusion and advanced medical management.

Methods

Air Verses Oxygen In myocarDial infarction study (AVOID Study) is a prospective, multi-centre, randomized, controlled trial conducted by Ambulance Victoria and participating metropolitan Melbourne hospitals with primary percutaneous coronary intervention capabilities. The purpose of the study is to determine whether withholding routine supplemental oxygen therapy in patients with acute ST-elevation myocardial infarction but without hypoxia prior to reperfusion decreases myocardial infarct size. AVOID will enroll 490 patients, >18 years of age with acute ST-elevation myocardial infarction of less than 12 hours duration.

Conclusions

There is an urgent need for clinical trials examining the role of oxygen in AMI. AVOID will seek to clarify this important issue. Results from this study may have widespread implications on the treatment of AMI and the use of oxygen in both the pre-hospital and hospital settings.

Section snippets

Background

Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide.1 In particular, many patients with CAD present with ST-elevation myocardial infarction (STEMI) as a result of acute thrombotic coronary artery occlusion. The optimal treatment for patients presenting with STEMI is reperfusion therapy either with primary percutaneous coronary intervention (PCI) or administration of a thrombolytic drug.2, 3

Current guidelines recommend additional treatments for patients with

Study sites

This study will be conducted by Ambulance Victoria in partnership with 12 major metropolitan hospitals in Melbourne, Australia. The Mobile Intensive Care Ambulances (MICA) of Ambulance Victoria are equipped with 12 lead electrocardiogram (ECG) capability and pulse-oximetry monitors and have significant experience in successfully conducting pre-hospital clinical trials in critically ill patients.21, 22 Ambulance Victoria, also has a Melbourne wide field triage 12-lead ECG program to detect STEMI

Data collection

A study coordinator will extract all relevant study data to a secure stand alone study database.

Summary

Despite inhaled oxygen therapy being a routine component of pre-hospital and in-hospital care for AMI, there is concern that rendering patients hyperoxic may increase myocardial infarct size and possibly lead to worse outcomes. This has led to international guidelines cautioning against the use of routine oxygen in normoxic patients with uncomplicated AMI. The AVOID study will be one of the first clinical trials in the modern era of pre-hospital ECG field triage and PPCI to investigate the role

Disclosures

Conflicts of Interest: None to declare.

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  • Cited by (53)

    • Conservative versus liberal oxygen therapy for acutely ill medical patients: A systematic review and meta-analysis

      2021, International Journal of Nursing Studies
      Citation Excerpt :

      Using the grading of recommendations, assessment, development, and evaluation summary of the evidence, the quality of evidence of primary outcome was high (eTable 3). Seventeen trials (NCT 00414726) (Ali et al., 2014; Asfar et al., 2017; Baekgaard et al., 2019; Barrot et al., 2020; Butler et al., 1987; Girardis et al., 2016; He et al., 2019; Hofmann et al., 2017; Jakkula et al., 2018; Panwar et al., 2016; Ranchord et al., 2012; Roffe et al., 2017; Ronning and Guldvog, 1999; Schietroma et al., 2016; Singhal et al., 2005; Stub et al., 2012) reported all-cause mortality at 30 days. There was no significant difference in all-cause mortality at 30 days between the conservative and liberal oxygen therapy group (risk ratio 1.09, 95% confidence intervals 0.98–1.22; I2=0%; Fig. 2).

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    Clinical Trial Registration: The AVOID study has been registered with clinicaltrials.gov (NCT01272713).

    f

    Dr Stub and Dr Smith contributed equally to this manuscript.

    g

    On behalf of AVOID Investigators. See online Appendix for complete listing.

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