Development of a swine animal model for the study of sudden infant death syndrome

An animal model with selective cardiac autonomic denervation was developed in neonatal swine for the purpose of future studies concerning the possible role of abnormal cardiac innervation in the etiology of sudden infant death syndrome. Twenty-six 4- to 8-day old piglets were randomly assigned to one of the following treatment groups: right stellate ganglionectomy (RSG), left stellate ganglionectomy (LSG), right cardiac vagotomy (RCV), and sham-operated control group. Piglets were anesthetized with Saffan and mechanically ventilated on room air. The thoracic wall was opened, and the sternum was divided, permitting exposure of pleura, heart, and lungs. After completion of one of these operative procedures, the thoracic wall was closed in layers. On successful recovery from anesthesia and extubation, piglets were returned to their sows. Postoperative administration of antibiotics was performed during the first week. Electrocardiograms were recorded once a week over an 8-week period. The sham-operated control group had a postnatal increase in QTc and decrease in heart rate. The RSG group had significantly longer QTc than the sham-operated control group QTc, whereas the RCV group had significantly shorter QTc interval than sham-operated controls. Surgical complications caused the death of two piglets (hemorrhage in one and aspiration in the other), infection caused the death of one piglet 2 weeks after surgery, and three died of unknown causes (one from the RSG group and two from the RCV group). The cause of death for these three animals could not be determined (necropsy was not revealing) because they were not monitored at the time of their demise.(ABSTRACT TRUNCATED AT 250 WORDS)