Underappreciated by providers: discuss anesthesia risks associated with obesity.(Obstetrics)

FORT MYERS, FLA. -- Certain risks associated with the use of anesthesia in obese women are underappreciated by obstetric care providers, and even the most well-known anesthetic risks are not routinely discussed with obese patients, Dr. Jill M. Mhyre said at the annual meeting of the Society for Obstetric Anesthesia and Perinatology.

In a survey of 37 obstetric care providers, many were not familiar with several anesthesia-related risks that are greater in obese patients, Dr. Mhyre, of the University of Michigan, Ann Arbor, reported in a poster presentation. (See box.)

The lack of knowledge about the risk for respiratory suppression with opioids is of particular concern, she noted, because obstetric care providers in most hospitals supervise the administration of intravenous opioids for labor analgesia.

The care providers were knowledgeable about several other risks that are more common in obese than in nonobese women and that are of interest to anesthesiologists, but the working definitions of obesity and the recommendations for pregnancy weight gain in obese women varied widely.

For example, the Institute of Medicine defines obesity as a body mass index (BMI) of greater than 30, yet only 42% of respondents used this definition. Other definitions included weight greater than 100 kg, weight 25% or 35% over ideal body weight, and BMI of at least 35. Also, IOM guidelines call for a 15- to 25-pound weight gain in obese women during a singleton pregnancy, but more than 60% of the respondents recommended greater weight gain.

In a related poster based on the same survey, Dr. Mhyre reported that the risks least likely to be discussed with patients during the prenatal period were those related to anesthesia.

Among the well-recognized obesity-related risks, those that were most often discussed with patients (by more than 60% of respondents) were gestational diabetes, hypertension, macrosomia, ...