A later anesthetic session may not reproduce the first session’s physiological baseline.
A telemetric rat study repeated anesthetic regimens, including medetomidine–midazolam–fentanyl. Physiological measures and tolerability changed differently across the regimens; the midazolam-containing mixture showed changes in pulse pressure with repeated exposure.
Repeated observations within animals are not independent human cases. The mixture does not isolate midazolam, and changes may involve adaptation, procedure effects or other components.
For serial procedures, review baseline values and prior exposures instead of assuming that the same administered amount must reproduce the same response. The experiment supports attention to session history, while it cannot quantify human tolerance or predict the next anesthetic outcome.
Source: PMC4301083, supplied full-text paper. Findings are paraphrased; case-review implications are an interpretation.
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