Integration of the Duke Activity Status Index into preoperative risk evaluation: a multicentre prospective cohort study.

BACKGROUND: The Duke Activity Status Index (DASI) questionnaire might help incorporate self-reported functional capacity into preoperative risk assessment. Nonetheless, prognostically important thresholds in DASI scores remain unclear. We conducted a nested cohort analysis of the Measurement of Exercise Tolerance before Surgery (METS) study to characterise the association of preoperative DASI scores with postoperative death or complications. METHODS: The analysis included 1546 participants (≥40 yr of age) at an elevated cardiac risk who had inpatient noncardiac surgery. The primary outcome was 30-day death or myocardial injury. The secondary outcomes were 30-day death or myocardial infarction, in-hospital moderate-to-severe complications, and 1 yr death or new disability. Multivariable logistic regression modelling was used to characterise the adjusted association of preoperative DASI scores with outcomes. RESULTS: The DASI score had non-linear associations with outcomes. Self-reported functional capacity better than a DASI score of 34 was associated with reduced odds of 30-day death or myocardial injury (odds ratio: 0.97 per 1 point increase above 34; 95% confidence interval [CI]: 0.96-0.99) and 1 yr death or new disability (odds ratio: 0.96 per 1 point increase above 34; 95% CI: 0.92-0.99). Self-reported functional capacity worse than a DASI score of 34 was associated with increased odds of 30-day death or myocardial infarction (odds ratio: 1.05 per 1 point decrease below 34; 95% CI: 1.00-1.09), and moderate-to-severe complications (odds ratio: 1.03 per 1 point decrease below 34; 95% CI: 1.01-1.05). CONCLUSIONS: A DASI score of 34 represents a threshold for identifying patients at risk for myocardial injury, myocardial infarction, moderate-to-severe complications, and new disability.

Lobar occlusion in the preoperative assessment of patients with lung cancer.

Bronchial occlusion during exercise was used to predict the functional effects of subsequent pulmonary resection in six high risk patients with lung cancer and severe airflow obstruction. Each patient underwent transnasal fibreoptic bronchoscopy whilst cycling in steady state at a load which had been selected as equivalent to walking at a brisk pace for that patient. The effects on minute ventilation and oxygen uptake were observed during occlusion of the bronchus to the diseased lobe. If the patient was able to continue cycling and maintain the same work load during occlusion this was regarded as indicating that he would withstand resection of the occluded lung tissue. In five of the patients, postoperative studies were performed. All were able to maintain the same level of steady state exercise postoperatively as that maintained during bronchial occlusion preoperatively. Resection resulted in a decrease in static lung volumes. Other routine whole lung function tests, walking capacity and incremental exercise indices, however, were largely unchanged.