A change in medication exposure does not guarantee a detectable change in every downstream biomarker.
In a 103-patient substudy of a randomized sedation trial, fewer dexmedetomidine-group patients received midazolam, and the doses were lower than in usual care. Despite that regimen difference, measured stress hormones and other assayed physiological markers did not differ significantly between groups over the observation period.
Patients received combinations of agents, and usual care was not a uniform midazolam-only comparator. Sampling intervals and critical illness complicate interpretation. The substudy cannot isolate the effect of removing midazolam or establish that all stress responses were identical.
For expert review, distinguish drug exposure, sedation depth and the biomarker selected to represent stress. A lower benzodiazepine dose should not automatically be described as lower physiological stress. Conversely, unchanged hormone results do not prove equal subjective experience or equal clinical outcomes.
Source: Publication PMC9682690, read from the supplied PDF. Applications to expert analysis are interpretation.
Related reading: Historical and New Benzodiazepine Use Had Different Acute-Care Associations in Opioid Users.