Aärimaa T, Välimäki I A
Department of Pediatrics, University Central Hospital, University of Turku, Finland.
Biol Neonate. 1988;54(4):188-94. doi: 10.1159/000242851.
Respiratory rate (RR), transthoracic electric impedance (TEZ) and transcutaneous PO2 and PCO2 were monitored during the 5 first postnatal days in 54 neonates on three separate occasions. There was no difference in the overall RR between the term and healthy preterm babies on different days of recordings but RR of the babies with RDS (who were all ventilated) was lower on day 1 (p less than 0.01). When the power spectrum of the TEZ respirogram was computed and the spectral density was divided into low-frequency (LF, less than 0.20 Hz) and high-frequency (HF, greater than 0.20 Hz) areas, the LF/HF ratio of healthy preterm babies was greater than that of term babies on day 1 (p less than 0.01). The preterm babies with RDS did not differ from the term babies in this respect. The LF/HF ratio was negatively correlated with gestational age and it had a positive correlation to PtcO2 (p less than 0.05) and PtcCO2 (p less than 0.01) (R2 = 0.07). The result evidences that the control of respiration changes in relation to maturity and the LF/HF ratio is a quantitative indicator of respiratory variability reflecting this development.
在出生后的头5天内，对54名新生儿分三次分别监测呼吸频率（RR）、经胸电阻抗（TEZ）以及经皮氧分压和二氧化碳分压。足月儿和健康早产儿在不同记录日的总体RR没有差异，但患有呼吸窘迫综合征（均接受机械通气）的婴儿在第1天的RR较低（p<0.01）。当计算TEZ呼吸图的功率谱并将频谱密度分为低频（LF，<0.20Hz）和高频（HF，>0.20Hz）区域时，健康早产儿在第1天的LF/HF比值高于足月儿（p<0.01）。患有呼吸窘迫综合征的早产儿在这方面与足月儿没有差异。LF/HF比值与胎龄呈负相关，与经皮氧分压（p<0.05）和经皮二氧化碳分压（p<0.01）呈正相关（R2=0.07）。结果表明，呼吸控制与成熟度有关，LF/HF比值是反映这种发育的呼吸变异性的定量指标。
