Intraoperative Malignant Hyperthermia Management

Immediate Actions

The first action for intraoperative malignant hyperthermia is to immediately stop all trigger agents, including volatile anesthetic agents and succinylcholine, as recommended by the British Journal of Anaesthesia 1, 2, 3
Stop all volatile inhalation anesthetic agents immediately and disconnect the vaporizer, as suggested by the British Journal of Anaesthesia 1, 3
Hyperventilate with 100% oxygen, using a minute volume 2-3 times normal with high flow, to help eliminate volatile anesthetics and address hypercarbia, as recommended by the British Journal of Anaesthesia 2, 3, 4
Declare an emergency and call for help, as advised by the British Journal of Anaesthesia 1
Change to non-trigger anesthesia (TIVA - Total Intravenous Anesthesia), as recommended by the British Journal of Anaesthesia 4
Inform the surgeon and request termination/postponement of surgery, as suggested by the British Journal of Anaesthesia 1

Administer dantrolene 2 mg/kg IV, with a maximum dose that may exceed 10 mg/kg if necessary, as recommended by the British Journal of Anaesthesia 1, 2, 3
Obtain additional dantrolene from pharmacy/nearby hospitals, as at least 36-50 ampoules may be needed for an adult patient, as advised by the British Journal of Anaesthesia 2
Repeat dantrolene infusions until cardiac and respiratory systems stabilize, as suggested by the British Journal of Anaesthesia 3
Continue routine anesthetic monitoring, including core temperature measurement, as recommended by the British Journal of Anaesthesia 1

Establish IV access with good IV lines and wide-bore cannulas, as advised by the British Journal of Anaesthesia 2
Treat hyperthermia by administering chilled saline IV and applying surface cooling, as recommended by the British Journal of Anaesthesia 3
Treat hyperkalemia with dextrose, insulin, and calcium, as suggested by the British Journal of Anaesthesia 1
Treat acidosis by hyperventilating to normocapnia and giving sodium bicarbonate IV if pH < 7.2, as recommended by the British Journal of Anaesthesia 2

Monitor the patient for a minimum of 24 hours in ICU/HDU, as advised by the British Journal of Anaesthesia 1, 3
Refer the patient and family to a regional MH center for investigation, as recommended by the British Journal of Anaesthesia 1
Arrange for diagnostic testing using in vitro contracture testing (IVCT), as suggested by the British Journal of Anaesthesia 3
The European Malignant Hyperthermia Group (EMHG) guidelines emphasize that early recognition and immediate treatment are essential for patient survival, with stopping trigger agents being the critical first step in management, as recommended by the European Malignant Hyperthermia Group 1, 3