Hyperbaric oxygen preconditioning improves myocardial function, reduces length of intensive care stay, and limits complications post coronary artery bypass graft surgery.
OBJECTIVE
The objective of this study was to determine whether preconditioning coronary artery disease (CAD) patients with HBO(2) prior to first-time elective on-pump cardiopulmonary bypass (CPB) coronary artery bypass graft surgery (CABG) leads to improved myocardial left ventricular stroke work (LVSW) post CABG. The primary end point of this study was to demonstrate that preconditioning CAD patients with HBO(2) prior to on-pump CPB CABG leads to a statistically significant (P<.05) improvement in myocardial LVSW 24 h post CABG.


METHODS
This randomised control study consisted of 81 (control group=40; HBO(2) group=41) patients who had CABG using CPB. Only the HBO(2) group received HBO(2) preconditioning for two 30-min intervals separated 5 min apart. HBO(2) treatment consisted of 100% oxygen at 2.4 ATA. Pulmonary artery catheters were used to obtain perioperative hemodynamic measurements. All routine perioperative clinical outcomes were recorded. Venous blood was taken pre HBO(2), post HBO(2) (HBO(2) group only), and during the perioperative period for analysis of troponin T.


RESULTS
Prior to CPB, the HBO(2) group had significantly lower pulmonary vascular resistance (P=.03). Post CPB, the HBO(2) group had increased stroke volume (P=.01) and LVSW (P=.005). Following CABG, there was a smaller rise in troponin T in HBO(2) group suggesting that HBO(2) preconditioning prior to CABG leads to less postoperative myocardial injury. Post CABG, patients in the HBO(2) group had an 18% (P=.05) reduction in length of stay in the intensive care unit (ICU). Intraoperatively, the HBO(2) group had a 57% reduction in intraoperative blood loss (P=.02). Postoperatively, the HBO(2) group had a reduction in blood loss (11.6%), blood transfusion (34%), low cardiac output syndrome (10.4%), inotrope use (8%), atrial fibrillation (11%), pulmonary complications (12.7%), and wound infections (7.6%). Patients in the HBO(2) group saved US$116.49 per ICU hour.


CONCLUSIONS
This study met its primary end point and demonstrated that preconditioning CAD patients with HBO(2) prior to on-pump CPB CABG was capable of improving LVSW. Additionally, this study also showed that HBO(2) preconditioning prior to CABG reduced myocardial injury, intraoperative blood loss, ICU length of stay, postoperative complications, and saved on cost, post CABG.
Yogaratnam
Jeysen Zivan
JZ
Department of Cardiothoracic Surgery, Castle Hill Hospital, Castle Road, HU16 JQ Cottingham, United Kingdom. jeysenzy@msn.com
Laden
Gerard
G
Guvendik
Levant
L
Cowen
Mike
M
Cale
Alex
A
Griffin
Steve
S
D000368:Aged; D015415:Biomarkers / Q000097:blood; D016063:Blood Loss, Surgical / Q000517:prevention & control; D002315:Cardiopulmonary Bypass; D002407:Catheterization, Swan-Ganz; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000191:economics; D003362:Cost-Benefit Analysis; D017558:Elective Surgical Procedures; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000191:economics / Q000209:etiology / Q000517:prevention & control*; D006439:Hemodynamics; D017721:Hospital Costs; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000191:economics; D007362:Intensive Care Units / Q000191:economics; D007902:Length of Stay; D008297:Male; D011300:Preoperative Care; D020127:Recovery of Function; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D020107:Troponin T / Q000097:blood; D016277:Ventricular Function, Left
D015415:Biomarkers; D020107:Troponin T