To the Editor:—
We appreciate the excellent analysis by Morray et al. 1of 150 anesthesia-related pediatric cardiac arrests reports submitted to the Pediatric Perioperative Cardiac Arrest Registry from 1994–1997. In his editorial, Rothstein 2suggests a multicenter prospective epidemiologic study to improve our understanding of the causes of pediatric perioperative anesthesia-related arrests and to develop a strategy to diminish their incidence.
We have some questions about the etiology of the hyperkalemic cardiac arrests reported to the Pediatric Perioperative Cardiac Arrest Registry. How many pediatric arrests were attributed to hyperkalemia? How many were unrelated to massive transfusion, liver reperfusion, and renal insufficiency? Did an additional three patients with unrecognized cardiomyopathy have arrests after halothane induction? Was skeletal muscle for histologic examination and dystrophin analysis obtained in any of these children? Was a positive family history of muscular dystrophy revealed when parents were interviewed after their child’s arrest? Do the reports indicate whether the etiology of occult myopathy was considered by the reporting institutions for these eight children and the eight additional children in whom no specific cardiovascular cause could be determined?
We ask because of our findings from a smaller study of all pediatric cardiac arrests (n = 25) reported predominantly from community hospitals for the years 1990–1993 to the databases of The North American Malignant Hyperthermia Registry and the Malignant Hyperthermia Association of the United States Hotline. 3Our analysis showed the presence of unrecognized myopathy in 12 arresting patients (48%), with 8 of these 12 cardiac arrests associated with hyperkalemia. Only 5 patients (20%) in our series experienced a malignant hyperthermia event before arrest.
To understand the causes of pediatric perioperative cardiac arrest better, we proposed 3that postarrest evaluation should include analysis of body fluids for electrolyte abnormality and skeletal muscle for myopathy and absence of normal dystrophin. As a strategy to decrease the incidence of myopathy-associated cardiac arrest, we urged pediatricians to screen young male patients for occult myopathy before their referral for elective anesthetics. We also asked whether presymptomatic diagnosis of Duchenne and Becker muscular dystrophies might be accomplished with neonatal creatine kinase testing. 4
Based on the study of Morray et al. 1and our findings, we concur that a large, multicenter prospective epidemiologic study that seeks to determine the etiology of all pediatric perioperative cardiac arrests would be of great value to the anesthesia community. We would be happy to collaborate in that venture.