Masseter muscle rigidity, elevated creatine kinase, and rhabdomyolysis following succinylcholine administration: a...

Area of Science:

• Anesthesiology
• Pediatric Medicine
• Neuromuscular Disorders

Background:

• Malignant hyperthermia (MH) is a rare, life-threatening pharmacogenetic disorder of skeletal muscle.
• Anesthetic agents like sevoflurane and succinylcholine can trigger MH in susceptible individuals.
• Early recognition and management are critical to prevent severe outcomes.

Observation:

• A 12-year-old boy presented with masseter muscle rigidity shortly after sevoflurane induction and succinylcholine administration.
• The patient had no prior history of neuromuscular disease or malignant hyperthermia.
• Within 75 minutes, the rigidity progressed to hyperkalemia, metabolic acidosis, and rhabdomyolysis.

Findings:

• The clinical presentation strongly suggests a hypermetabolic crisis, consistent with malignant hyperthermia susceptibility.
• Elevated creatine kinase levels were noted, indicating muscle breakdown.
• The absence of a prior history does not exclude the possibility of MH.

Implications:

• This case highlights the importance of considering MH even in patients without a known family or personal history.
• A comprehensive workup, including muscle biopsy, is recommended to confirm or exclude MH susceptibility.
• Until further evaluation, the patient should be considered "malignant hyperthermia susceptible" for future anesthetic management.