Program screens for sleep apnea

1/12/2012 12:00 AM

By Stephen Aufderheide, MD

​Sacred Heart Medical Center has launched a pilot program to improve the safety of total joint surgery. For the past several months, patients scheduled for joint replacement surgery at the hospital have been screened for obstructive sleep apnea using a simple, eight-question survey.

Obstructive sleep apnea is a disorder that can cause abnormal pauses in breathing while sleeping. In severe cases, these pauses can happen hundreds of times a night. A surprising number of people with sleep apnea remain undiagnosed, a fact that can lead to complications during and after surgery.

Sleep apnea is most prevalent in obese, middle-aged men, but can also occur in women and average-weight people. An estimated 82 percent of men and 92 percent of women with moderate to severe sleep apnea remain undiagnosed. Untreated sleep apnea can contribute to high blood pressure, stroke, heart problems, diabetes, depression, and even car accidents.

It can also cause complications during and after surgery, especially when narcotic medications are used to treat the pain of surgery.

Sacred Heart is using a screening survey, called the STOP-BANG questionnaire, which has been validated in several studies. For example, in a recent study, patients with high-risk scores experienced higher rates of post-operative complications -- 19.6 percent compared to 1.3 percent for patients with low-risk scores.

The STOP-BANG questionnaire poses eight yes or no questions about risk factors for sleep apnea, including age, weight, snoring, breathing pauses, fatigue, blood pressure, neck circumference and gender. Patients who answer yes to three or more questions are at higher risk for sleep apnea and may be referred to a sleep physician for consultation and a sleep study.

Joint replacement patients with untreated sleep apnea have higher incidence of low oxygen levels after surgery when they are treated with narcotics, but the long-term effects are unknown and are still being studied.

Between May and November 2011, 310 patients were referred to a sleep physician, according to Connie Dunks, supervisor of the Sleep Disorders Center at Sacred Heart. In rare cases, surgery had to be delayed to allow for consultation and diagnosis.

Since sleep apnea requires long-term treatment with long-term outcomes, screening would ideally be performed as a routine part of primary care, similar to diabetes and blood pressure testing. Until outpatient diagnosis and treatment of sleep apnea becomes more commonplace, Sacred Heart will continue to screen joint replacement patients before surgery. In the future, Sacred Heart may make sleep apnea screening mandatory for all previously untested elective surgery patients.

Currently, all patients scheduled for elective surgery at Sacred Heart are given an appointment at the hospital's pre-op anesthesia clinic. About 98 percent of patients attend those appointments, which are seen as opportunities to improve the overall medical care of the patient, in addition to planning for surgery. To that end, staff and anesthesiologists review vaccinations and screen for hypertension, diabetes, pulmonary problems, cardiac disease -- and now, sleep apnea.

Anesthesiologist Stephen Aufderheide, MD, is Medical Director of the Anesthesia Department at Sacred Heart Medical Center.