DOI: https://doi.org/10.36347/sjmcr.2026.v14i05.036

Pages: 1016-1019

Remimazolam is an ultra-short-acting benzodiazepine increasingly used for anesthetic induction due to its hemodynamic stability. However, as its use expands, reports of perioperative hypersensitivity reactions are accumulating. We report a case of isolated refractory circulatory collapse suspected to be caused by remimazolam during anesthetic induction. This case highlights the diagnostic challenge of distinguishing hypersensitivity reactions presenting solely as cardiovascular collapse from anesthesia-induced vasodilation. A 58-year-old male undergoing elective laparoscopic cholecystectomy developed severe hypotension within minutes of remimazolam administration. Due to previous encounters of remimazolam hypersensitivity reaction in our clinic, preventive measures for hypersensitivity were done before induction. Remimazolam was first diluted with normal saline using a filter needle and administration was done through an in-line filter. Despite these measures, the patient exhibited profound hypotension without bronchospasm, cutaneous signs, electrocardiographic abnormalities, or metabolic derangement. Anesthesia-induced vasodilation was initially suspected, but the condition progressed to non-measurable blood pressure and was refractory to repeated intravenous ephedrine boluses. Hemodynamics rapidly improved following administration of intravenous epinephrine. Although serum tryptase was not measured, intradermal testing three weeks later demonstrated a positive response to remimazolam. Though the concentration used during intradermal testing may have exceeded non-irritating thresholds, the relationship between remimazolam exposure and circulatory collapse, together with the prompt hemodynamic response to epinephrine was considered consistent with remimazolam-associated perioperative hypersensitivity. This case demonstrates that remimazolam hypersensitivity may present as isolated refractory circulatory collapse, highlighting the importance of considering hypersensi