A patient, Tina was anesthetized with halothane and nitrous oxide and tubocurarine was used for skeletal muscle relaxation. She became hypertensive along with marked muscle rigidity and hyperthermia. Lab reports showed that she has developed hyperkalemia and acidosis. This complication was caused by:
The symptoms of the patient (muscle rigidity, hypertension, hyperthermia, hyperkalemia and acidosis) suggest the diagnosis of malignant hyperthermia.
Halothane can precipitate malignant hyperthermia in susceptible individuals. SCh increases this incidence.
Malignant hyperthermia is due to excessive release of Ca2+ from the sarcoplasmic reticulum.
Drug of choice for malignant hyperthermia is dantrolene that inhibits the release of Ca2+ (by blocking ryanodine re­ceptors in the sarcoplasmic reticulum).
Block of autonomic ganglia by tubocurarine
Pheochromocytoma
Activation of brain dopamine receptors by halothane
Excessive release of calcium from the sarcoplasmic reticulum