Preoperative 6MWD Research Articles

Preoperative change in 6-minute walk distance correlates with early weight loss after sleeve gastrectomy.

Introduction:The 6-minute walk test (6MWT) is an objective preoperative measure of functional capacity and response to intervention in patients with heart or lung disease. In bariatric surgery, there has been no reliable preoperative measure predictive of postoperative success. Here we investigated the impact of bariatric surgery on changes in distance traveled in the 6MWT (the 6MWD) and whether preoperative changes in 6MWD correlated with weight change after surgery.Methods:This is a retrospective study of consecutive patients in which the 6MWT was performed before and after laparoscopic sleeve gastrectomy for weight loss. 6MWD and total weight were measured. Pearson correlation was used to determine association between variables.Results:Of 100 patients who underwent laparoscopic sleeve gastrectomy, 31 patients had a preoperative 6MWT. Thirty patients (97%) were available for follow-up after surgery. Percentage of excess weight loss was 45.7% over an average of 7 months after surgery. There was a weak correlation between the postoperative weight loss and the change in preoperative and postoperative 6MWD (r = 0.28; P = .13). In a subset of patients who demonstrated a change in distance traveled in 2 separate preoperative 6MWD measurements (average 18.5% increase in distance), there was a strong correlation with postoperative weight loss (r = 0.82; P = .02).Conclusions:A demonstrated increase in 6MWD before surgery correlates strongly with early postoperative weight loss after laparoscopic sleeve gastrectomy. A multidisciplinary team that includes a physical therapist is useful in preparing bariatric patients for surgery.

Utility of Six-Minute Walk Distance in Predicting Outcomes after Lung Transplant: A Nationwide Survival Analysis

<h3>Purpose</h3> Currently the Lung Allocation Score (LAS) dichotomizes 6-minute walk distance (6MWD) at 150 ft. We hypothesized that increasing 6MWD considered as a continuous variable would be associated with improved survival after lung transplant. <h3>Methods and Materials</h3> Adult, first time, lung-only transplantations per the United Network for Organ Sharing database from 04/2005-12/2011 were analyzed. Generalized linear models were used to determine the association between preoperative 6MWD and post-transplant survival after adjusting for potential confounders. <h3>Results</h3> 9,013 patients were included for analysis. The median 6MWD was 810 feet (25th-75th percentiles=520-1100 feet). Increasing 6MWD quartile was associated with significantly improved survival. [figure 1] As a continuous variable, increasing 6MWD was associated with significantly lower mortality at 90-days [adjusted odds ratio (AOR) per 500 feet 0.90, 95% confidence interval (CI) 0.83-0.98, p=0.02], 1-year (AOR 0.89, CI 0.83-0.95, p<0.001), and 3-years (AOR 0.92, CI 0.85-1.00, p=0.04) as well as reduced overall hazard of death (adjusted hazard ratio per 500 feet 0.86, CI 0.82-0.90, p<0.0001). Based on recursive partitioning, stratification of 6MWD by over/under 730 feet provided maximal separation in 1-year mortality. <h3>Conclusions</h3> 6MWD as a continuous variable is significantly associated with post-transplant survival. Strategies to improve patient functional status preoperatively, including aggressive rehabilitation efforts, could therefore impact post-transplant survival. Future iterations of the LAS should consider the full range of 6MWD values in order to provide maximum prognostic information regarding post-transplant survival.