Identification of a Family With Inherited Long QT Syndrome After a Pediatric Near-drowning

Near-drowning continues to be a largely preventable tragedy frequenting emergency rooms across the country. After motor vehicle-related deaths, drowning is the second most common accident causing death in children.1,2 Several epidemiologic studies have examined the risk factors associated with near-drowning in the pediatric population including lack of supervision, trauma, alcohol, and seizures.3-7 Cardiac arrhythmias may be an important consideration for drowning survivors and their family when a plausible explanation is lacking. In this report, a boy whose near-drowning in a public pool was caused most likely by a ventricular tachyarrhythmia is described. After discovery of the probable cause of his near-drowning, several additional family members were identified as having inherited long QT syndrome (LQTS). A previously healthy 10-year-old white boy was brought to the Emergency Room at Mayo Eugenio Litta Children's Hospital by emergency medical services in acute respiratory distress after being retrieved from the bottom of a public pool. History available at the time was limited and the duration of submersion was unknown. Reportedly, the near drowning victim was “racing” his younger brother. There was no suggestion of trauma and no past medical history of epilepsy. Paramedics were called, cardiopulmonary resuscitation was started, and the near drowning victim was defibrillated at poolside (Fig 1). Fig. 1. Record of torsades de pointes at the near drowning scene. The tracing shown is the police defibrillator record obtained at the scene shortly after retrieval from the pool. The subject was defibrillated with 200 joules twice before converting from this polymorphic ventricular tachyarrhythmia to normal sinus rhythm (admission weight = 56 kg). Arterial blood gas determination revealed a metabolic acidosis: pH 7.05, Paco2 47, HCO3 13, and −17 base deficit. The patient was paralyzed, sedated, intubated, and brought to the pediatric intensive care unit after cervical spine …