Pancuronium causes vagal blockade and sympathetic stimulation, thereby placing the patient at risk for tachycardia.
The patient is exhibiting symptoms of malignant hyperthermia (MH). Succinylcholine and halogenated volatile anesthetics are known to trigger MH episodes. MH is characterized by intense muscle contractions and increased metabolic demands. MH is believed to result from an intracellular derangement not involving cell membrane receptors. Dantrolene acts to decrease the intracellular release of calcium from the sarcoplasmic reticulum, thereby relaxing muscle tissue and reversing the symptoms of MH. Because MH is not mediated by cell membrane receptors, the other muscle relaxants listed are ineffective in its treatment.
Cisatracurium breaks down spontaneously in vivo ("Hoffman elimination"). Therefore its elimination is virtually unaffected by the patient's renal and hepatic dysfunction. Succinylcholine would have prolonged effects in this patient because its elimination is dependent on the hepatic production of plasma cholinesterase. Furthermore the increased potassium levels resulting from succinylcholine administration would be of particular concern in this patient with end-stage renal disease.