Suspected Malignant Hyperthermia During Tibia Fixation
A 24-year-old man is undergoing open reduction and internal fixation of a tibia fracture under general anesthesia with sevoflurane and succinylcholine. About 45 minutes into the case, end-tidal CO2 rises from 38 to 68 mmHg despite increased ventilation, heart rate goes from 82 to 138 beats/min, and temperature rises to 39.3°C. The masseter muscles were stiff after induction. The soda lime canister feels hot. The surgeon is placing a drain and says he needs 10 more minutes to finish. The malignant hyperthermia cart is at the back of the room, and the surgical technologist is scrubbed with instruments on the field.
1. What is your first priority, and what actions should you take as the surgical technologist?
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Recognize this as a likely malignant hyperthermia crisis and call for help immediately. The anesthesia team must stop the triggering agents, provide 100% oxygen at high flow, hyperventilate, and give dantrolene according to the MH protocol. As the surgical technologist, your priorities are to support the resuscitation without delaying it:
- Announce the concern clearly and ask the circulating nurse to bring the MH cart and call for additional help.
- Stop passing instruments and prepare to abandon or rapidly finish the procedure as directed; the surgeon may need to pack and close quickly.
- Assist with dantrolene preparation if trained and needed, while protecting the sterile field as much as possible.
- Help obtain cold intravenous saline, ice packs for the groin and axillae, cooling blankets, and monitoring supplies.
- Do not leave the patient unattended, and do not insist on completing the scheduled procedure.
The tech should not independently diagnose or administer drugs, but should be an active extra pair of hands and a calm communicator.
2. What postoperative and equipment actions are needed after the acute crisis?
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The patient needs intensive monitoring for recrudescence, hyperkalemia, rhabdomyolysis, acute kidney injury, coagulopathy, and compartment syndrome. Dantrolene is continued per the MH protocol, often for at least 24 hours and then tapered, with monitoring of urine output and laboratory values. Transfer to an ICU with adequate staffing and prepare a complete handoff including the agents used, temperature trend, dantrolene doses, fluids, and urine output.
For the anesthesia equipment, follow the facility's MH protocol and manufacturer instructions: remove the vaporizers, replace the breathing circuit and soda lime, and flush the machine with 100% oxygen for the recommended time before the next case. The surgical technologist should help remove and isolate contaminated supplies, restock the MH cart, and document the event. The patient and family should be referred for MH susceptibility evaluation and counseling.
3. How should the team communicate and document during this emergency?
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Use loud, closed-loop communication with named roles: "You, bring the MH cart; you, call the OR charge nurse; anesthesia, do you want dantrolene mixed?" Keep messages short and confirm they were heard. The surgeon should be told directly that the case needs to stop or be abbreviated because of a life-threatening anesthetic emergency, not given a vague warning.
Document the time the signs were recognized, the triggers stopped, the dantrolene doses and times, cooling measures, temperature and vital-sign trends, laboratory specimens sent, and the patient's response. Complete an incident report per policy and debrief the team afterward. Documentation should be contemporaneous and factual because MH events are high-risk and may be reviewed for quality and patient follow-up.