Relationship of shuttle walk test and lung cancer surgical outcome

Objective: Surgery remains the treatment of choice in patients with potentially resectable lung carcinoma. Both the British Thoracic Society and American Chest Physician guidelines for the selection of patients with lung cancer surgery suggest the use of a shuttle walk test to predict outcome in patients with borderline lung function. The guidelines suggest that if the patient is unable to walk 250 m during a shuttle walk test, they are high risk for surgery. However, there is no published evidence to support this recommendation. Therefore, we undertook a prospective study to examine the relationship between shuttle walk test and surgical outcome in 139 patients undergoing assessment for possible lung cancer surgery. Methods: The shuttle walk test was performed in 139 potentially resectable patients, recruited over a 2 year period, prior to surgery. One hundred and eleven patients underwent surgery. Outcome of surgery, including duration of hospital stay, complication and mortality rates was recorded. Student's t-test was used to compare the shuttle walk distance in patients with good and poor outcome from surgery. Results: Mean age of patients undergoing surgery was 69 years (42–85). Mean shuttle walk distance was 395 m (145–780), with a mean oxygen desaturation of 4% (0–14) during the test. Sixty nine patients had a good surgical outcome and 34 had a poor outcome. The shuttle walk distance was not statistically different in the two outcome groups. Conclusion: Shuttle walk distance should not be used to predict poor surgical outcome in lung cancer patients, contrary to current recommendations. It is therefore advisable to perform a formal cardiopulmonary exercise test if at all possible. The usefulness of a shuttle walk test might be improved. It could be compared to a predicted value, as for a formal cardiopulmonary exercise test.     

Comparison of shuttle walk with measured peak oxygen consumption in patients with operable lung cancer

BACKGROUND: The relationship between the shuttle walk test and peak oxygen consumption in patients with lung cancer has not previously been reported. A study was undertaken to examine this relationship in patients referred for lung cancer surgery to test the hypothesis that the shuttle walk test would be useful in this clinical setting. METHODS: 125 consecutive patients with potentially operable lung cancer were prospectively recruited. Each performed same day shuttle walking and treadmill walking tests. RESULTS: Shuttle walk distances ranged from 104 m to 1020 m and peak oxygen consumption ranged from 9 to 35 ml/kg/min. The shuttle walk distance significantly correlated with peak oxygen consumption (r = 0.67, p<0.001). All 55 patients who achieved more than 400 m on the shuttle test had a peak oxygen consumption of at least 15 ml/kg/min. Seventy of 125 patients failed to achieve 400 m on the shuttle walk test; in 22 of these the peak oxygen consumption was less than 15 ml/kg/min. Nine of 17 patients who achieved less than 250 m had a peak oxygen consumption of more than 15 ml/kg/min. CONCLUSION: The shuttle walk is a useful exercise test to assess potentially operable lung cancer patients with borderline lung function. However, it tends to underestimate exercise capacity at the lower range compared with peak oxygen consumption. Our data suggest that patients achieving 400 m on the shuttle walk test do not require formal measurement of oxygen consumption. In patients failing to achieve this distance we recommend assessment of peak oxygen consumption, particularly in those unable to walk 250 m, because a considerable proportion would still qualify for surgery as they had an acceptable peak oxygen consumption.     

An attempt to analyze the relation between hospital surgical volume and clinical outcome

Objectives The aim of this study was to investigate the relation between hospital volume and clinical surgical outcome for 10 cardiac, lung, and esophageal surgical procedures. Methods The Committee for Scientific Affairs of the Japanese Association for Thoracic Surgery collected the pooled data on cardiac, lung, and esophageal surgical procedures between 2000 and 2004 from the annual reports. The relation between operative mortality (30-day or in-hospital mortality) and hospital volume was analyzed using a logistic regression model. The surgical procedures studied were surgery for acquired cardiac diseases [coronary artery bypass grafting (CABG), valve procedures, acute type A dissection surgery], total CABG (elective + emergency), elective CABG, emergency CABG, single-valve surgery, acute type A dissection surgery, open heart surgery for the newborn, open heart surgery for the infants, lung cancer surgery, and esophageal cancer surgery. The data used in this study were not risk-adjusted. Results The data on the relation between hospital volume and operative mortality generally tended to show an inverse correlation for all 10 cardiac, lung, and esophageal surgical procedures; that is, the higher was the volume the lower was the mortality. However, wide variations in operative mortality were noted among the very-low-volume hospital groups. Conclusion An inverse correlation was noted between hospital volume and operative mortality in the present study, although wide variations in clinical outcome were noted among the very low-volume hospitals. Further analysis is warranted using risk-adjusted data. This report was prepared by the Committee for Scientific Affairs, The Japanese Association for Thoracic Surgery