title: Very Transient Cases of Acute Kidney Injury in the Early Postoperative Period After Cardiac Surgery: The Relevance of More Frequent Serum Creatinine Assessment and Concomitant Urinary Biochemistry Evaluation.
abstract: OBJECTIVE
  To evaluate if more frequent serum creatinine (sCr) measurements in the early postoperative period (first 48 hours) after cardiac surgery would help in early diagnosis of acute kidney injury (AKI), as well as reveal cases of AKI duration of fewer than 24 hours (vtAKI). The sequential blood and urinary biochemical profile of patients who developed vtAKI was compared with that of the patients who did not develop AKI or who developed AKI for more than 48 hours (pAKI).
  
  
  METHODS
  A retrospective analysis of prospectively collected data.
  
  
  METHODS
  Two intensive care units of 2 private hospitals.
  
  
  METHODS
  Twenty-nine patients who underwent cardiac surgery who had 6 values of serum creatinine (sCr) measured within the first 48 hours after surgery and concomitant spot urine samples for urine biochemistry assessment.
  
  
  METHODS
  None.
  
  
  RESULTS
  Eighteen patients (62%) developed Acute Kidney Injury Network (AKIN) sCr-based AKI, half of them for fewer than 24 hours. Most AKI patients had the sCr increase diagnosed 6 to 12 hours after surgery. When comparing the sequential alterations of blood and urinary parameters among patients with no AKI, vtAKI, and pAKI, the authors found that most of them were similar among groups, differing only in magnitude and duration.
  
  
  CONCLUSIONS
  More frequent sCr measurements in the early postoperative period, together with urine biochemistry assessment, have the potential to anticipate AKI diagnosis after cardiac surgery and reveal cases of very transient AKI usually not diagnosed in current practice. The clinical relevance of these findings must be evaluated in larger, prospective studies.
authors: Imed Research Group;; Intensive Care Unit, Hospital São Camilo Pompéia;; Intensive Care Unit, Department of Medical Emergencies, Hospital das Clínicas, University of São Paulo. Electronic address: alexandre.toledo@imedgroup.com.br.
authors: Alexandre Toledo
authors: AT
authors: Maciel
authors: Imed Research Group;; Intensive Care Unit, Hospital Sa¨o Camilo Santana, São Paulo, Brazil.
authors: Antonio Paulo
authors: AP
authors: Nassar
authors: Imed Research Group;; Intensive Care Unit, Hospital São Camilo Pompéia;
authors: Daniel
authors: D
authors: Vitorio
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000175:diagnosis / Q000652:urine*; D000368:Aged; D015415:Biomarkers / Q000097:blood / Q000652:urine; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood*; D005260:Female; D006801:Humans; D007677:Kidney Function Tests / Q000379:methods; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood* / Q000175:diagnosis / Q000652:urine*; D011184:Postoperative Period; D011446:Prospective Studies; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers; D003404:Creatinine
keywords: acute kidney injury; cardiac surgery; urine biochemistry; very transient physicochemical approach