Related Experiment Video
Updated: Oct 20, 2026

Hypercapnic Hyperventilation to Accelerate Emergence from Inhaled Volatile Anesthetics: A Practical Method Using Standard Hospital Equipment
Published on: June 26, 2026
Factitious halothane detection during trigger-free anesthesia in a malignant hyperthermia susceptible patient
1Department of Anesthesiology, Queen's University, Kingston General Hospital, Ontario. chawk@nb.sympatico.ca
Purpose:
To discuss the problems encountered when halothane was detected in a presumed 'clean' patient circuit during the 'trigger-free' anesthetic management of a known Malignant Hyperthermia Susceptible (MHS) patient for routine orthopedic surgery.
Clinical Features:
A 29-yr-old MHS woman had a wrist arthroscopy/exploration/fusion under general anesthesia. During the course of the 'trigger-free' anesthetic the respiratory gas analyser detected end-tidal halothane in the patient circuit. The patient was disconnected from the circuit as attempts to identify the source of the readings were undertaken. After ruling out the presence of halothane by various clinical manoeuvre the patient was reconnected to the circuit without sequelae.
Conclusion:
By exclusion the problem was presumed to be a factitious reading resulting from the respiratory gas analyser incorrectly identifying patient-expired methane as halothane.
More Related Videos
Related Concept Videos
Inhalational Anesthetics: Overview
Increased Body Temperature
Acute Respiratory Failure-III
Depolarizing Blockers: Pharmocokinetics
Hypoglycemia and Glucagon

