The effect of mannitol on oxygenation and creatine kinase MB release in patients undergoing multivessel off-pump coronary artery bypass surgery.
OBJECTIVE
Despite avoiding cardiopulmonary bypass, off-pump coronary artery bypass surgery is associated with reduction in PaO2 and postoperative respiratory compliance. Also, transient interruption of coronary flow is necessary during distal anastomoses and may impose ischemia-reperfusion myocardial injury. Mannitol is an osmotic diuretic with free radical scavenging properties, and we have evaluated the effects of mannitol on oxygenation and cardiac enzyme release in patients undergoing multivessel off-pump bypass surgery in a prospective, randomized, controlled, double-blind trial.


METHODS
Fifty patients were randomly allocated to receive either 20% mannitol 0.5 g/kg (n = 25) or normal saline 2.5 mL/kg (n = 25) during Y-graft construction. Pulmonary variables and serum sodium concentrations were measured 15 minutes after induction of anesthesia and sternum closure. Creatine kinase MB was measured before and after the operation. Intraoperative and postoperative fluid input and output, time to extubation, and intraoperative hemodynamic variables were also recorded.


RESULTS
PaO2 after sternum closure was significantly higher in the mannitol group, with faster time to extubation and shorter length of stay in the intensive care unit. Intraoperative urine output was significantly greater in the mannitol group, without significant differences in fluid input, serum sodium concentration, and hemodynamic variables. Number of patients with a creatine kinase MB level more than 3 times the upper limit of normal was significantly higher in the control group.


CONCLUSIONS
Mannitol could be safely used without adverse side effects in patients undergoing multivessel off-pump bypass surgery with beneficial effects in terms of preserving oxygenation, earlier extubation, and fewer patients with significant creatine kinase MB elevation.
Shim
Jae Kwang
JK
Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, South Korea.
Choi
Seung Ho
SH
Oh
Young Jun
YJ
Kim
Chang Seok
CS
Yoo
Kyung Jong
KJ
Kwak
Young Lan
YL
D000368:Aged; D001784:Blood Gas Analysis; D017023:Coronary Angiography; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D052279:Creatine Kinase, MB Form / Q000187:drug effects* / Q000378:metabolism; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007262:Infusions, Intravenous; D007430:Intraoperative Care; D008297:Male; D008353:Mannitol / Q000627:therapeutic use*; D008875:Middle Aged; D010101:Oxygen Consumption / Q000187:drug effects*; D011183:Postoperative Complications / Q000517:prevention & control; D011300:Preoperative Care; D011336:Probability; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange; D012016:Reference Values; D018570:Risk Assessment; D015996:Survival Rate; D016896:Treatment Outcome
D008353:Mannitol; D052279:Creatine Kinase, MB Form