Point-of-care creatinine measurements to predict acute kidney injury

Suvi T. Vaara, Neil Glassford, Glenn M. Eastwood, Emmanuel Canet, Johan Mårtensson, Rinaldo Bellomo

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Background: Plasma creatinine (Cr) is a marker of kidney function and typically measured once daily. We hypothesized that Cr measured by point-of-care technology early after ICU admission would be a good predictor of acute kidney injury (AKI) the next day in critically ill patients. Methods: We conducted a retrospective database audit in a single tertiary ICU database. We included patients with normal first admission Cr (CrF) and identified a Cr value (CrP) obtained within 6-12 hours from ICU admission. We used their difference converted into percentage (delta-Cr-%) to predict subsequent AKI (based on Cr and/or need for renal replacement therapy) the next day. We assessed predictive value by calculating area under the receiver characteristic curve (AUC), logistic regression models for AKI with and without delta-Cr-%, and the category-free net reclassifying index (cfNRI). Results: We studied 780 patients. Overall, 70 (9.0%) fulfilled the Cr AKI definition by CrP measurement. On day 2, 148 patients (19.0%) were diagnosed with AKI. AUC (95% CI) for delta-Cr-% to predict AKI on day 2 was 0.82 (95% CI 0.78-0.86), and 0.74 (95% CI 0.69-0.80) when patients with AKI based on the CrP were excluded. Using a cut-off of 17% increment, the positive likelihood ratio (95% CI) for delta-Cr-% to predict AKI was 3.5 (2.9-4.2). The cfNRI was 90.0 (74.9-106.1). Conclusions: Among patients admitted with normal Cr, early changes in Cr help predict AKI the following day.

Original languageEnglish
Pages (from-to)766-773
Number of pages8
JournalActa Anaesthesiologica Scandinavica
Volume64
Issue number6
DOIs
Publication statusPublished - Jul 2020

Keywords

  • acute kidney injury
  • creatinine
  • critically ill
  • point-of-care
  • prediction

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