title: Peripheral Edema, Central Venous Pressure, and Risk of AKI in Critical Illness.
abstract: OBJECTIVE
  Although venous congestion has been linked to renal dysfunction in heart failure, its significance in a broader context has not been investigated.
  
  
  METHODS
  Using an inception cohort of 12,778 critically ill adult patients admitted to an urban tertiary medical center between 2001 and 2008, we examined whether the presence of peripheral edema on admission physical examination was associated with an increased risk of AKI within the first 7 days of critical illness. In addition, in those with admission central venous pressure (CVP) measurements, we examined the association of CVPs with subsequent AKI. AKI was defined using the Kidney Disease Improving Global Outcomes criteria.
  
  
  RESULTS
  Of the 18% (n=2338) of patients with peripheral edema on admission, 27% (n=631) developed AKI, compared with 16% (n=1713) of those without peripheral edema. In a model that included adjustment for comorbidities, severity of illness, and the presence of pulmonary edema, peripheral edema was associated with a 30% higher risk of AKI (95% confidence interval [95% CI], 1.15 to 1.46; P<0.001), whereas pulmonary edema was not significantly related to risk. Peripheral edema was also associated with a 13% higher adjusted risk of a higher AKI stage (95% CI, 1.07 to 1.20; P<0.001). Furthermore, levels of trace, 1+, 2+, and 3+ edema were associated with 34% (95% CI, 1.10 to 1.65), 17% (95% CI, 0.96 to 1.14), 47% (95% CI, 1.18 to 1.83), and 57% (95% CI, 1.07 to 2.31) higher adjusted risk of AKI, respectively, compared with edema-free patients. In the 4761 patients with admission CVP measurements, each 1 cm H2O higher CVP was associated with a 2% higher adjusted risk of AKI (95% CI, 1.00 to 1.03; P=0.02).
  
  
  CONCLUSIONS
  Venous congestion, as manifested as either peripheral edema or increased CVP, is directly associated with AKI in critically ill patients. Whether treatment of venous congestion with diuretics can modify this risk will require further study.
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts;
authors.forename: Kenneth P
authors.initials: KP
authors.lastname: Chen
authors.affiliation: Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts;
authors.forename: Susan
authors.initials: S
authors.lastname: Cavender
authors.affiliation: Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts; School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada; and.
authors.forename: Joon
authors.initials: J
authors.lastname: Lee
authors.affiliation: Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts; Data Analytics Department, Institute for Infocomm Research, Agency for Science, Technology And Research, Singapore.
authors.forename: Mengling
authors.initials: M
authors.lastname: Feng
authors.affiliation: Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts;
authors.forename: Roger G
authors.initials: RG
authors.lastname: Mark
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts;
authors.forename: Leo Anthony
authors.initials: LA
authors.lastname: Celi
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts;
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Mukamal
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; jdanzige@bidmc.harvard.edu.
authors.forename: John
authors.initials: J
authors.lastname: Danziger
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology* / Q000209:etiology*; D000368:Aged; D002496:Central Venous Pressure; D016638:Critical Illness; D004487:Edema / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment
keywords: acute kidney injury; acute renal failure; central venous pressure; comorbidity; critical illness; edema; heart failure; humans; pulmonary edema; renal function