[Anesthetic complications. The incidence of severe anesthetic complications in patients and families with progressive muscular dystrophy of the Duchenne and Becker types].

UNLABELLED: During the last 30 years a great number of case reports presented severe anaesthetic complications with sudden cardiac arrest in patients with muscular dystrophies, mostly unsuspected at the time of the event. As succinylcholine was involved in the majority of the intractable incidents with lethal outcome the Food and Drug Administration (FDA) of the United States recommended a warning of the administration of succinylcholine in young children and adolescents in 1992 and an extensive international discussion on the routine use of succinylcholine in paediatric anaesthesia. Epidemiological studies on this issue are rare. We projected an inquiry about the incidence rate and type of severe anaesthetic complications in an utmost large number of patients and families with Duchenne (DMD) and Becker type (BMD) muscular dystrophy.
METHODS: With the approval of the ethic committee of the university Witten/Herdecke and informed consent of the participants we investigated all patients and families who were diagnosed, controlled and treated for DMD or BMD as inpatients or outpatients in a "Muscle Centre" since 1983. The questionnaire asked for the number of patients per family, classification of the disease DMD or BMD, number and date of anaesthetics in the patients and eventual complications, anaesthetics and eventual complications in the parents, siblings and relatives and the occurrence of malignant hyperthermia (MH) in the family or relatives. Statistical assessments were done by Fisher's exact test for stratified 2 x 2 tables and Zelen's test for homogeneity of odds ratios.
RESULTS: 200 out of 224 questionnaires could be evaluated. The diagnosis was confirmed by molecular genetic and immunohistochemical investigations. In 147 families it turned out to be DMD, in 53 families BMD. The 212 male and 9 female patients in the 200 families were given 444 anaesthetics. Sudden cardiac arrest occurred in 6 patients, all successfully resuscitated. Nine less severe incidents consisted of fever, symptoms of rhabdomyolysis (CK-elevation, dark coloured urine, hyperkalemia) and masseter spasm. The statistical assessment revealed that the occurrence of an event was highly dependent whether the diagnosis of muscular dystrophy was established or not (p < 0.0001, Fisher's exact test). All six cardiac arrests occurred in the 45 families with undiagnosed disease and no event happened in the 134 families with already known DMD/BMD. There was evidence that the number of anaesthetics without prior establishment of the diagnosis decreased after 1992 (p = 0.004, Fisher's exact test).
CONCLUSIONS: Our results demonstrate that severe incidents and cardiac arrests occurred only in young children with undiagnosed DMD or BMD who received inhalational agents and succinylcholine. A cardiac arrest in 6 out of 200 families was found much more frequently than in the normal paediatric population (about 1:1000 to 1:3000). The decrease of events after 1992 (warning of the FDA) and disappearance of sudden cardiac arrests in our group of patients might be due to the world wide discussion on routine use of succinylcholine in children or the much earlier establishment of the diagnosis in our population. An early diagnosis of DMD and BMD and the avoidance of the triggering agents succinylcholine and volatile anaesthetics can reduce the risk of severe anaesthetic complications.