Cohen G, Henderson-Smart D J
Department of Perinatal Medicine, King George V Memorial Hospital, Camperdown, Sydney, Australia.
J Dev Physiol. 1990 Nov;14(5):295-301.
Measurement of the ventilatory response of the newborn to carbon dioxide using the rebreathing method usually involves raising the concentration of oxygen in the inspired gas in order to prevent hypoxaemia developing during the test. Described here is a modified rebreathing method which avoids the need to use hyperoxic gas mixtures. Subjects rebreathed 5-7% carbon dioxide in air for 1.5-3 min; hypoxaemia was prevented by the addition of oxygen to the rebreathing circuit at the rate of approximately 7 ml/min per kg body weight. Arterial oxygen saturation (measured by a pulse oximeter) was maintained at approximately 95% throughout the tests. The technique was successfully used to study the ventilatory responses of eight full-term and 4 pre-term babies during behaviorally defined rapid-eye movement and quiet sleep. The reproducibility of the ventilatory response measured by this method was evaluated by repeated testing of each subject. This revealed considerable variability in the magnitude of the response from test to test. Some of the factors which might contribute to this variability are discussed.
使用重复呼吸法测量新生儿对二氧化碳的通气反应，通常需要提高吸入气体中的氧气浓度，以防止在测试过程中出现低氧血症。本文描述了一种改良的重复呼吸法，该方法无需使用高氧气体混合物。受试者在空气中重复呼吸含5 - 7%二氧化碳的气体1.5 - 3分钟；通过以大约每公斤体重每分钟7毫升的速率向重复呼吸回路中添加氧气来防止低氧血症。在整个测试过程中，动脉血氧饱和度（通过脉搏血氧仪测量）维持在大约95%。该技术成功用于研究8名足月儿和4名早产儿在行为学定义的快速眼动睡眠和安静睡眠期间的通气反应。通过对每个受试者进行重复测试，评估了用该方法测量的通气反应的可重复性。这显示出每次测试反应幅度存在相当大的变异性。讨论了可能导致这种变异性的一些因素。
