In sheep undergoing general anaesthesia does inclusion of medetomidine result in hypoxaemia?

• DOI: 10.18849/ve.v10i2.708
• Publication Date: 2025-05-06T08:52:59Z
• Authors: Rachael Gregson

Question In healthy adult female non-pregnant sheep undergoing general anaesthesia for research studies does the inclusion of intravenous medetomidine as part anaesthetic protocol cause hypoxaemia? Clinical bottom line The category question was: Treatment. number and type study designs that were critically appraised were: Four papers available critical appraisal. quality evidence is weak. There four experimental studies; three which cross-over one was run in parallel with primary orthopaedic research. None specifically focussed on potential hypoxaemic effects medetomidine. Critical appraisal selected meeting criteria collectively provide zero/weak/moderate/strong terms their design implementation: Weak. outcomes reported are summarised follows… Sheep across all developed hypoxaemia (indicated by arterial oxygen tension; either PaO2 < 80 mmHg/10 kPa when breathing room air, or a statistically significant fall compared baseline, enriched gases), administered intravenously combination various drugs (i.e. midazolam, propofol, ketamine, halothane, isoflurane). However, receiving doses at timepoints, different quantities supplemental (if any), varying ventilatory management (two used mechanical ventilation two allowed to breathe spontaneously), agents maintain anaesthesia, clinical significance values difficult assess. view strength from following conclusion made… clinically (judged examination) (characterised placement an endotracheal tube and/or use induction i.e. barbiturates, propofol), weak presented here suggests can be expected hypoxaemia. variable its lessened techniques such provision oxygen.