Is morbid obesity a factor leading to last-minute cancellation of outpatient surgery? No, according to a small study that concluded that body mass index (BMI) over 50, long considered a contraindication for outpatient surgery, does not cause day-of-surgery cancellations and that ambulatory anesthesia can be safely provided to morbidly obese patients without co-morbidity.
Researcher Jeffrey Huang, MD, of Anesthesiologists of Greater Orlando (Fla.), included in the study all patients scheduled for various surgeries during a six-month period at a surgery center. He classified a patient as a last-minute cancellation if the patient's name was on the published operating room schedule, but he didn’t have surgery performed on the day scheduled.
Of the 1,167 cases scheduled during the six-month period, 28 were canceled at the last minute. There were 13 no-shows (non-medically related), eight acute upper respiratory infections, three cases in which the medical condition resolved (passing stone, for example) and one case of failing to comply with NPO status. Of the four cases involving patients with BMI >50, none was cancelled.
In 1992, the Royal College of Surgeons issued Guidelines for Day Case Surgery. Patients with a BMI >30 were deemed unsuitable for outpatient surgery, a recommendation recent literature has challenged, says Dr. Huang. BMI over 45 is now recommended as a cut-off number.
Obese and morbidly obese patients are at high risk for difficult airway management, cardiopulmonary dysfunction, aspiration and markedly increased perioperative morbidity and mortality. "The use of modern advanced anesthesia has increased the safety of anesthesia in morbid obesity patients," says Dr. Huang. The only parameter predictive of difficult intubation in morbidly obese patients, he adds, seems to be the circumference of the neck, but not the BMI.
—Dan O’Connor
