title: Lung size mismatch and primary graft dysfunction after bilateral lung transplantation.
abstract: BACKGROUND
  Donor-to-recipient lung size matching at lung transplantation (LTx) can be estimated by the predicted total lung capacity (pTLC) ratio (donor pTLC/recipient pTLC). We aimed to determine whether the pTLC ratio is associated with the risk of primary graft dysfunction (PGD) after bilateral LTx (BLT).
  
  
  METHODS
  We calculated the pTLC ratio for 812 adult BLTs from the Lung Transplant Outcomes Group between March 2002 to December 2010. Patients were stratified by pTLC ratio >1.0 ("oversized") and pTLC ratio ≤1.0 ("undersized"). PGD was defined as any ISHLT Grade 3 PGD (PGD3) within 72 hours of reperfusion. We analyzed the association between risk factors and PGD using multivariable conditional logistic regression. As transplant diagnoses can influence the size-matching decisions and also modulate the risk for PGD, we performed pre-specified analyses by assessing the impact of lung size mismatch within diagnostic categories.
  
  
  RESULTS
  In univariate analyses oversizing was associated with a 39% lower odds of PGD3 (OR 0.61, 95% CI, 0.45-0.85, p = 0.003). In a multivariate model accounting for center-effects and known PGD risks, oversizing remained independently associated with a decreased odds of PGD3 (OR 0.58, 95% CI 0.38 to 0.88, p = 0.01). The risk-adjusted point estimate was similar for the non-COPD diagnosis groups (OR 0.52, 95% CI 0.32 to 0.86, p = 0.01); however, there was no detected association within the COPD group (OR 0.72, 95% CI 0.29 to 1.78, p = 0.5).
  
  
  CONCLUSIONS
  Oversized allografts are associated with a decreased risk of PGD3 after BLT; this effect appears most apparent in non-COPD patients.
authors.affiliation: Division of Pulmonary, Critical Care and Occupational Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa. Electronic address: michael-eberlein@uiowa.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Eberlein
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Reed
authors.affiliation: Department of Thoracic Surgery, Dr. Horst Schmidt Klinik, Wiesbaden, Germany.
authors.forename: Servet
authors.initials: S
authors.lastname: Bolukbas
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Diamond
authors.affiliation: Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Keith M
authors.initials: KM
authors.lastname: Wille
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Orens
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Roy G
authors.initials: RG
authors.lastname: Brower
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Jason D
authors.initials: JD
authors.lastname: Christie
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008168:Lung / Q000033:anatomy & histology*; D016040:Lung Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D055031:Primary Graft Dysfunction / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D011446:Prospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D014019:Tissue Donors; D014109:Total Lung Capacity; D014184:Transplantation, Homologous; D014481:United States; D055815:Young Adult
keywords: lung size mismatch; lung transplantation; mechanical ventilation; primary graft dysfunction; tidal volume