Electrical Heart Activity Recorded During Prolonged Avalanche Burial
A man in his mid thirties activated an avalanche transceiver device, leading to a rescue effort that uncovered him at an elevation of 2750 m under 30 cm snow. The patient was assessed on site to be pulseless and was evacuated by helicopter, after which point he was declared dead. Cardiac activity, however, was obtained from a functioning watch and transmitting heart rate belt that recorded continuous data during his death. Five distinct phases of cardiac activity were noted during the avalanche: 1) 0 to 18 minutes, highly variable heart rate with a mean of 83 ± 25 beats/min; 2) 18 to 35 minutes, sustained heart rate of 154 beats/min; 3) 35 to 70 minutes, bradycardia with a mean of 51 ± 14 beats/min; 4) 70 to 253 min, sustained tachycardia with a mean of 176 ± 13 beats/min; and 5) 253 minutes, cardiac arrest. The manufacturer affirmed the accuracy of the data obtained from the heart rate monitor.
From the 5 phases of extracted electrical heart activity, correlations were made with the accepted survival patterns of avalanche victims, with survival probability dropping after 18 to 35 minutes owing to asphyxia, and again after 90 minutes as a result of hypoxia, hypercapnia, and hyperthermia. The authors' conjectured that the variability in the victim's heart activity during the first 18 minutes of burial was the result of enhanced autonomic activity secondary to asphyxia. No definitive conclusions were made regarding the association of hypothermia and variations in heart rate, nor why the skier had persistent tachycardia of 180 beats/min from 70 to 253 min. Limitations of this case report include the accuracy of the heart rate monitor and the lack of 12-lead capability.
(Img Card Med. 2012;125:646-647). S Giacomo, W Beikircher, E Procter, H Brugger.
Prepared by Phillip Hoverstadt, MD, UTMB-Galveston Medical School, Galveston, TX, USA