Fagenholz S A, Lee J C, Downing S E
Yale J Biol Med. 1979 May-Jun;52(3):263-70.
Central respiratory drive was studied in 13 piglets of both sexes varying in age from 19 to 67 days. The distal trachea was cannulated and the maximum rate of isometric inspiratory pressure change (dP/dt)(max), was measured at the airway. Curves were constructed relating this measurement to changes in arterial PCO(2) during carbon dioxide rebreathing. Data were obtained at intervals corresponding to stepwise reductions in central respiratory drive produced by added chloralose anaesthesia. Laryngeal reflex activation was achieved by electrical stimulation of the superior laryngeal nerves (SLN). This caused permanent respiratory arrest at a critical level of central respiratory depression expressed as the slope of the curve relating (dP/dt)(max) to arterial PCO(2). Severely anemic piglets showed markedly decreased central respiratory drive at a given dose of anesthesia compared to controls. This was consistent with the observed greater sensitivity to laryngeal nerve stimulation in these animals. It is concluded that anemia may be associated with impaired functional maturation of central respiratory mechanisms and consequent susceptibility to laryngeal reflex apnea and asphyxial death. These observations may pertain to factors associated with the sudden infant death syndrome.
对13头年龄在19至67天之间的雌雄仔猪进行了中枢呼吸驱动研究。将远端气管插管，并在气道处测量等长吸气压力变化的最大速率（dP/dt）（max）。构建曲线，将该测量值与二氧化碳再呼吸期间动脉PCO₂的变化相关联。在对应于添加水合氯醛麻醉导致的中枢呼吸驱动逐步降低的时间间隔获取数据。通过电刺激喉上神经（SLN）实现喉反射激活。这在以（dP/dt）（max）与动脉PCO₂相关曲线的斜率表示的中枢呼吸抑制的临界水平上导致永久性呼吸停止。与对照组相比，严重贫血的仔猪在给定剂量的麻醉下显示出明显降低的中枢呼吸驱动。这与在这些动物中观察到的对喉神经刺激的更高敏感性一致。结论是，贫血可能与中枢呼吸机制的功能成熟受损以及随之而来的对喉反射性呼吸暂停和窒息死亡的易感性有关。这些观察结果可能与婴儿猝死综合征相关的因素有关。
