Laryngeal chemosensitivity: a possible mechanism for sudden infant death.

摘要: In 32 anaesthetized piglets 1 to 42 days of age the distal trachea was cannulated and pressure changes were recorded. The proximal for introduction test fluids into laryngeal area. Arterial pressure, heart rate, central venous continuously blood samples obtained at intervals analyzed PO2, PCO2, pH, hematocrit. Normal saline produced no, or brief, transitory alterations respiratory pattern arterial pressure. contrast, instillation distilled water apnea in 29 30 piglets. 20 sustained. Eleven died within approximately 50 minutes asphyxia. An additional nine expected die with continuing (PO2, 10 15 mm Hg; PCO2 greater than 100 pH smaller 6.8) but sequence interrupted by replacement saline. Twenty-three showed an apneic response cow's milk similar that seen water. Seven asphyxia three sustained inhibition until replaced responses completely abolished superior nerve (SLN) sectioning. Electrical stimulation SLN seven eight tested. Studies two 3-day-old lambs discrimination only milk. Both during stimulation. Two ewes insignificant responses. These findings suggest a lethal reflex mechanism implications SIDS problem.