Hyperbaric preconditioning of the myocardium prior to ischaemia reperfusion improved some measures of myocardial injury and function.

1. Some evidence that hyperbaric preconditioning results in better myocardial function following coronary artery bypass grafting
2. Some evidence of reduced myocardial necrosis from ischaemia reperfusion injury

Citation/s:
1. Yogaratnam JZ, Laden G, Madden LA, Guvendik L, Cowen M, Greenman M, Seymour AM, Cale A, Griffin S. Hyperbaric oxygen preconditioning promotes cardioprotection following ischemic reperfusion injury by improving myocardial function, limiting necrosis and enhancing the induction of Hsp72. Undersea and Hyperbaric Medicine 2007; 34(4):301-302
Lead author's name and fax: Jaysen Yogaratnam, Dept Cardiac Surgery Castle Hill Hospital, Hull, UK

Three-part Clinical Question: For patients expected to undergo myocardial ischaemia-reperfusion injury, does preconditioning with hyperbaric oxygenation ameliorate the injury?
Search Terms: Ischaemia-reperfusion, CABG, myocardial function

The Study:
Single-blinded concealed randomised controlled trial with intention-to-treat.
The Study Patients: Patients scheduled to undergo coronary artery bypass grafting with cardiopulmonary bypass
Control group (N = 40; 40 analysed): Standard per-operative surgical management
Experimental group (N = 41 ; 41 analysed): Hyperbaric oxygenation four hours prior to CABG at 2.4 ATA for 90 minutes.

The Evidence:

Non-Event Outcomes

Time to outcome/s

Difference

P-value

Increase in stroke volume

24 hours post-op

Greater increase in experimental group

0.01

Left ventricular stroke work

24 hours post-op

Greater increase in experimental group

0.005

Comments:
1. Abstract only with limited data.
2. A single hyperbaric exposure rather than the three previously used by this group (see Alex)    

Appraised by: Mike Bennett, Sydney ; Friday, 7 December 2007
Email: m.bennett@unsw.edu.au
Kill or Update By: December 2008