Simbruner G, Popow C
Padiatr Padol. 1982;17(2):535-48.
The interaction of lung mechanics, peripheral lung reflexes and chemosensitivity of the respiratory center were studied in over 80 newborns. Healthy newborns (gestational age between 30 and 41 weeks) and newborns with respiratory distress syndrome (RDS) (gestational age between 29 and 40 weeks) were studied on the first day of life. Spontaneously breathing newborns were examined using the airway occlusion technique (AOT), and intubated babies using the injection technique (IT) to measure the compliance of the respiratory system (Crs), the strength of the inspiration inhibiting reflex (IIR) and inspiratory time during airway occlusion (Ti occ), and index of chemosensitivity of the respiratory center. Crs in healthy newborns increased only slightly but statistically significant (p less than 0.001) with gestational age. Crs of newborns with RDS had an overwhelming influence on their prognosis. Newborns with Crs of less than or equal to 1 developed respiratory failure and needed ventilatory support. Newborns with a Crs less than or equal to 0.5 died despite respiratory therapy. The activity of the peripheral vagally mediated reflex system also depended on the Crs. Our results indicate that the decrease in reflex activity with gestational age is not brought about by neurologic maturation but is caused by the increasing Crs. We conclude that the peripheral vagally mediated reflexes remain the same throughout life, just the boundary condition Crs, which is given by the lung mechanics, is different for premature or mature newborns and changes with age. The chemosensitivity of the respiratory center for CO2 was characterized by the inspiratory time after an expiratory occlusion (Ti occ) which is not influenced by lung mechanics. Ti occ correlated significantly with pCO2. The relation between Ti occ and pCO2 was similar for premature and mature, healthy and respiratory ill newborns. Consequently, chemosensitivity, expressed as the ratio of Ti occ and pCO2, is independent of gestational age.
对80多名新生儿的肺力学、外周肺反射和呼吸中枢化学敏感性之间的相互作用进行了研究。在出生第一天，对健康新生儿（胎龄30至41周）和患有呼吸窘迫综合征（RDS）的新生儿（胎龄29至40周）进行了研究。对自主呼吸的新生儿采用气道闭塞技术（AOT）进行检查，对插管婴儿采用注射技术（IT）来测量呼吸系统顺应性（Crs）、吸气抑制反射（IIR）强度和气道闭塞期间的吸气时间（Ti occ）以及呼吸中枢化学敏感性指标。健康新生儿的Crs仅随胎龄略有增加，但具有统计学意义（p小于0.001）。患有RDS的新生儿的Crs对其预后有压倒性影响。Crs小于或等于1的新生儿发生呼吸衰竭，需要通气支持。Crs小于或等于0.5的新生儿尽管接受了呼吸治疗仍死亡。外周迷走神经介导的反射系统的活动也取决于Crs。我们的结果表明，随着胎龄增加反射活动的降低不是由神经成熟引起的，而是由Crs增加所致。我们得出结论，外周迷走神经介导的反射在一生中保持不变，只是由肺力学决定的边界条件Crs对于早产或成熟新生儿不同，且随年龄变化。呼吸中枢对二氧化碳的化学敏感性以呼气闭塞后的吸气时间（Ti occ）为特征，其不受肺力学影响。Ti occ与pCO2显著相关。早产和成熟、健康和患病新生儿的Ti occ与pCO2之间的关系相似。因此，以Ti occ与pCO2的比值表示的化学敏感性与胎龄无关。
