Anaes SAQs · Applied cardiovascular & respiratory physiology
Context-sensitive half-time
Primary — CSHT definition (time for plasma concentration to halve after stopping an infusion of given duration); CSHT vs terminal half-life (fixed number vs infusion-duration-dependent); why CSHT rises with infusion duration for lipophilic drugs (peripheral compartment accumulation and reverse redistribution); the ester exception (remifentanil, esmolol, remimazolam — constant short CSHT); clinical relevance (opioid and hypnotic selection for long cases, transition analgesia, organ failure).
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Define the context-sensitive half-time (CSHT). Contrast it with the terminal elimination half-life and explain why the CSHT increases with infusion duration for some drugs but not others. Use specific anaesthetic examples.
References5ShowHide
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