TITLE:
Intraoperative Awareness with Recall Due to Inadvertent Use of Activated Charcoal Filters
AUTHORS:
Barry N. Swerdlow
KEYWORDS:
Awareness, Charcoal Filters, General Anesthesia, Malignant Hyperthermia, Recall
JOURNAL NAME:
Open Journal of Anesthesiology,
Vol.9 No.6,
June
27,
2019
ABSTRACT: A 57-year-old woman underwent abdominal surgery with a subarachnoid block supplemented by “light” general endotracheal anesthesia consisting of a propofol infusion and a sub-MAC concentration of sevoflurane. The previous case in the same operating room had involved a malignant hyperthermia-susceptible patient, and charcoal filters had been placed in the breathing circuit as a precautionary measure. Because it had not been used on the evening beforehand, the circuit with filters was left in situ with a strip of tape indicating that it was clean. The woman’s anesthesiologist assumed that these filters were heat and moisture exchanger filters in an unused circuit and therefore did not remove them. Subsequently, the patient had awareness with intraoperative recall. This case highlights the potential for inadvertent use of activated charcoal filters with potentially catastrophic results. Such unintended utilization of these products likely can be minimized by improved labeling techniques.