title: Association between transient acute kidney injury and morbidity and mortality after lung transplantation: a retrospective cohort study.
abstract: OBJECTIVE
  Acute kidney injury (AKI) is a common occurrence after lung transplantation (LTx). Whether transient AKI or early recovery is associated with improved outcome is uncertain. Our aim was to describe the incidence, factors, and outcomes associated with transient AKI after LTx.
  
  
  METHODS
  We performed a retrospective cohort study of all adult recipients of LTx at the University of Alberta between 1990 and 2011. Our primary outcome transient AKI was defined as return of serum creatinine below Kidney Disease-Improving Global Outcome AKI stage I within 7days after LTx. Secondary outcomes included occurrence of postoperative complications, mortality, and long-term kidney function.
  
  
  RESULTS
  Of 445 LTx patients enrolled, AKI occurred in 306 (68.8%) within the first week after LTx. Of these, transient AKI (or early recovery) occurred in 157 (51.3%). Transient AKI was associated with fewer complications including tracheostomy (17.2% vs 38.3%; P<.001), reintubation (16.4% vs 41.9%; P<.001), decreased duration of mechanical ventilation (median [interquartile range], 69 [41-142] vs 189 [63-403] hours; P<.001), and lower rates of chronic kidney disease at 3 months (28.5% vs 51.1%, P<.001) and 1 year (49.6% vs 66.7%, P=.01) compared with persistent AKI. Factors independently associated with persistent AKI were higher body mass index (per unit; odds ratio [OR], 0.91; 95% confidence interval, 0.85-0.98; P=.01), cyclosporine use (OR, 0.29; 0.12-0.67; P=.01), longer duration of mechanical ventilation (per hour [log transformed]; OR, 0.42; 0.21-0.81; P=.01), and AKI stages II to III (OR, 0.16; 0.08-0.29; P<.001). Persistent AKI was associated with higher adjusted hazard of death (hazard ratio, 1.77 [1.08-2.93]; P=.02) when compared with transient AKI (1.44 [0.93-2.19], P=.09) and no AKI (reference category), respectively.
  
  
  CONCLUSIONS
  Transient AKI after LTx is associated with fewer complications and improved survival. Among survivors, persistent AKI portends an increased risk for long-term chronic kidney disease.
authors.affiliation: Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, 2-124E Clinical Sciences Building, Edmonton, Alberta, Canada; Nephrology Department, Hospital Prof Dr Fernando Fonseca, Amadora, Portugal. Electronic address: fidalgo@ualberta.ca.
authors.forename: Pedro
authors.initials: P
authors.lastname: Fidalgo
authors.affiliation: Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, 2-124E Clinical Sciences Building, Edmonton, Alberta, Canada. Electronic address: mahmed3@ualberta.ca.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Ahmed
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, University of Alberta, Edmonton, Alberta, Canada. Electronic address: srmeyer@ualberta.ca.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Meyer
authors.affiliation: Division of Pulmonary Medicine, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. Electronic address: dale.lien@ualberta.ca.
authors.forename: Dale
authors.initials: D
authors.lastname: Lien
authors.affiliation: Division of Pulmonary Medicine, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. Electronic address: jw5@ualberta.ca.
authors.forename: Justin
authors.initials: J
authors.lastname: Weinkauf
authors.affiliation: Division of Pulmonary Medicine, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. Electronic address: akapasi@ualberta.ca.
authors.forename: Ali
authors.initials: A
authors.lastname: Kapasi
authors.affiliation: Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, 2-124E Clinical Sciences Building, Edmonton, Alberta, Canada; Gastroenterology Department, Hospital Prof Dr Fernando Fonseca, Amadora, Portugal. Electronic address: desousac@ualberta.ca.
authors.forename: Filipe S
authors.initials: FS
authors.lastname: Cardoso
authors.affiliation: Lung Transplant Program, Alberta Health Services, Edmonton, Alberta, Canada. Electronic address: Kathy.Jackson@albertahealthservices.ca.
authors.forename: Kathy
authors.initials: K
authors.lastname: Jackson
authors.affiliation: Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, 2-124E Clinical Sciences Building, Edmonton, Alberta, Canada. Electronic address: bagshaw@ualberta.ca.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Bagshaw
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D000328:Adult; D000367:Age Factors; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D015994:Incidence; D007677:Kidney Function Tests; D016040:Lung Transplantation / Q000009:adverse effects* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D016017:Odds Ratio; D011183:Postoperative Complications / Q000209:etiology; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology / Q000209:etiology; D012121:Respiration, Artificial / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014139:Tracheostomy / Q000706:statistics & numerical data
chemical_list: D003404:Creatinine
keywords: Acute kidney injury; Chronic kidney disease; Lung transplantation; Mortality; Recovery; Transient AKI