Malignant Hyperthermia in Dogs: Anaesthetic Welfare

Malignant hyperthermia is a rare but life-threatening anaesthetic emergency. This guide covers risk factors, recognition, and emergency management.

Key Facts

Malignant hyperthermia is triggered by volatile anaesthetic agents in susceptible individuals
Uncontrolled calcium release in skeletal muscle causes hyperthermia, rigidity, and acidosis
Certain breeds (Greyhounds, Labradors) may have increased susceptibility
Signs during anaesthesia include muscle rigidity, rapid temperature rise, and tachycardia
Dantrolene is the specific treatment — should be available in all veterinary anaesthetic settings
Without rapid treatment, death from multiorgan failure occurs quickly

Welfare Considerations and Management

Welfare-centred anaesthetic management requires preparation and rapid response. Any unexplained muscle rigidity or rapid temperature rise during anaesthesia should trigger immediate suspicion of malignant hyperthermia. The volatile anaesthetic agent must be discontinued immediately. Intravenous dantrolene, active cooling, oxygen, and cardiovascular support are the emergency treatment. Prior planning including dantrolene availability and emergency protocols saves lives in this rare but devastating complication.

What You Can Do

Inform your vet of any family history of anaesthetic complications before procedures
Ensure your vet clinic has dantrolene available for anaesthetic emergencies
Discuss lowest-risk anaesthetic protocols for susceptible breeds before any procedure
Monitor anaesthetised pets closely throughout recovery for delayed signs