Morbid obesity is associated with increased resource utilization in coronary artery bypass grafting

Studies have shown good outcomes for morbidly obese patients who undergo cardiac surgery. However, little is known about how much additional resource utilization treating these challenging patients requires. We hypothesized that morbidly obese patients (body mass index ≥40 kg/m(2)) undergoing coronary artery bypass grafting needed longer operating room times and had longer hospital and intensive care unit stays than non-morbidly obese patients.

We reviewed data from all morbidly obese patients (n = 56, body mass index = 42.7 ± 2.6 kg/m(2)) who underwent coronary artery bypass grafting at our institution between 1999 and 2009. These patients' outcomes were compared with those of non-morbidly obese patients (n = 168, body mass index = 30.0 ± 2.8 kg/m(2)) who were propensity-matched 3:1 with the morbidly obese patients.

Of the 14 preoperative characteristics examined, only 1, creatinine level, differed significantly between the two groups (p = 0.02). Intraoperative and postoperative complication rates and the mortality rate were similar between groups (p > 0.09). However, morbidly obese patients had longer operating times (449 ± 70 versus 420 ± 59 minutes; p = 0.002), intensive care unit stays (5.2 versus 3.3 days; p < 0.005), and postoperative hospital stays (14.2 versus 9.5 days; p < 0.005) than the non-morbidly obese patients.

Although good outcomes can be achieved for morbidly obese patients who undergo coronary artery bypass grafting, these patients require considerably more resource utilization in the operating room and intensive care unit, and they spend more time in the hospital after surgery. At a cardiac surgical operating room cost of approximately $50 per minute and $4,500 per intensive care unit day, the financial implications for morbidly obese patients who need coronary artery bypass grafting are not insignificant.