title: The societal impact of single versus bilateral lung transplantation for chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Bilateral lung transplantation (BLT) improves survival compared with single lung transplantation (SLT) for some individuals with chronic obstructive pulmonary disease (COPD). However, it is unclear which strategy optimally uses this scarce societal resource.
  
  
  OBJECTIVE
  To compare the effect of SLT versus BLT strategies for COPD on waitlist outcomes among the broader population of patients listed for lung transplantation.
  
  
  METHODS
  We developed a Markov model to simulate the transplant waitlist using transplant registry data to define waitlist size, donor frequency, the risk of death awaiting transplant, and disease- and procedure-specific post-transplant survival. We then applied this model to 1,000 simulated patients and compared the number of patients under each strategy who received a transplant, the number who died before transplantation, and total post-transplant survival.
  
  
  RESULTS
  Under baseline assumptions, the SLT strategy resulted in more patients transplanted (809 vs. 758) and fewer waitlist deaths (157 vs. 199). The strategies produced similar total post-transplant survival (SLT = 4,586 yr vs. BLT = 4,577 yr). In sensitivity analyses, SLT always maximized the number of patients transplanted. The strategy that maximized post-transplant survival depended on the relative survival benefit of BLT versus SLT among patients with COPD, donor interval, and waitlist size.
  
  
  CONCLUSIONS
  In most circumstances, a policy of SLT for COPD improves access to organs for other potential recipients without significant reductions in total post-transplant survival. However, there may be substantial geographic variations in the effect of such a policy on the balance between these outcomes.
authors.affiliation: Section of Pulmonary and Critical Care Medicine, Dartmouth-Hitchcock Medical Center, Dartmouth Medical School, Lebanon, NH 03756, USA. jeffrey.c.munson@Hitchcock.org
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Munson
authors.forename: Jason D
authors.initials: JD
authors.lastname: Christie
authors.forename: Scott D
authors.initials: SD
authors.lastname: Halpern
mesh_terms: D003661:Decision Support Techniques; D015276:Health Care Rationing / Q000379:methods*; D006801:Humans; D016040:Lung Transplantation / Q000379:methods*; D008390:Markov Chains; D029424:Pulmonary Disease, Chronic Obstructive / Q000601:surgery*; D012042:Registries; D016019:Survival Analysis; D014850:Waiting Lists