Urinary and renal oxygenation during dexmedetomidine infusion in critically ill adults with mechanistic insights from an ovine model

Mark P. Plummer, Yugeesh R. Lankadeva, Mark E. Finnis, Anatole Harrois, Charlie Harding, Rachel M. Peiris, Nobuki Okazaki, Clive N. May, Roger G. Evans, Christopher M. Macisaac, Deborah Barge, Rinaldo Bellomo, Adam M. Deane

Research output: Contribution to journalArticleResearchpeer-review

6 Citations (Scopus)

Abstract

Purpose: Examine effects of dexmedetomidine on bladder urinary oxygen tension (PuO2) in critically ill patients and delineate mechanisms in an ovine model. Materials and methods: In 12 critically ill patients: oxygen-sensing probe inserted in the bladder catheter and dexmedetomidine infusion at a mean (SD) rate of 0.9 ± 0.3 μg/kg/h for 24-h. In 9 sheep: implantation of flow probes around the renal and pulmonary arteries, and oxygen-sensing probes in the renal cortex, renal medulla and bladder catheter; dexmedetomidine infusion at 0.5 μg/kg/h for 4-h and 1.0 μg/kg/h for 4-h then 16 h observation. Results: In patients, dexmedetomidine decreased bladder PuO2at 2 (−Δ11 (95% CI 7–16)mmHg), 8 (−Δ 7 (0.1–13)mmHg) and 24 h (−Δ 11 (0.4–21)mmHg). In sheep, dexmedetomidine at 1 μg/kg/h reduced renal medullary oxygenation (−Δ 19 (14–24)mmHg) and bladder PuO2 (−Δ 12 (7–17)mmHg). There was moderate correlation between renal medullary oxygenation and bladder PuO2; intraclass correlation co-efficient 0.59 (0.34–0.80). Reductions in renal medullary oxygenation were associated with reductions in blood pressure, cardiac output and renal blood flow (P < 0.01). Conclusions: Dexmedetomidine decreases PuO2in critically ill patients and in sheep. In sheep this reflects a decrease in renal medullary oxygenation, associated with reductions in cardiac output, blood pressure and renal blood flow.

Original languageEnglish
Pages (from-to)74-81
Number of pages8
JournalJournal of Critical Care
Volume64
DOIs
Publication statusPublished - Aug 2021

Keywords

  • Critical illness
  • Dexmedetomidine
  • Oxygenation
  • Renal

Cite this