Background

Patients with severe obesity are known to have significant rates of hypertension, diabetes mellitus, and perceived poor functional capacity, often prompting preoperative cardiac testing before bariatric surgery. We hypothesized the vast majority of bariatric patients can achieve metabolic equivalents (METS), and therefore do not need additional preoperative cardiac testing beyond a simple electrocardiogram.

Methods

We introduced the Duke Activity Status Index (DASI) into our bariatric preoperative evaluation. The DASI is a validated set of 12 yes/no questions used to predict a patient's functional capacity. We describe DASI results in a typical bariatric population along with other well-known perioperative cardiac risk predictors.

Results

398 patients completed a DASI questionnaire. Mean age was 44+-12 years, 78% were female, 50% had hypertension, 40% had hyperlipidemia, 40% had sleep apnea, and 28% had diabetes mellitus. Mean body mass index was 47+-9 kg/m2. 12.6% of patients had 2 or more Revised Cardiac Risk Index predictors of cardiac risk. The functional capacity, estimated by DASI, averaged 7.5 +- 2.2 METS and was >4 METS in 92% of patients. For higher risk patients with METS<4, 32% underwent echocardiograms, 48% underwent stress tests, and 3% underwent cardiac catheterizations. For patients with predicted METS >4, there was less testing: 13% underwent echocardiograms, 12% underwent stress tests, and 1.6% underwent cardiac catheterization. No patient had a perioperative cardiac event.

Conclusions

DASI is a simple and objective tool to estimate preoperative functional capacity in bariatric patients. Incorporation of DASI into bariatric preoperative evaluation can reduce the need for cardiac testing.