Bhat Prashanth, Patel Deena-Shefali, Hannam Simon, Rafferty Gerrard F, Peacock Janet L, Milner Anthony D, Greenough Anne
Division of Asthma, Allergy and Lung Biology, MRC Centre for Allergic Mechanisms in Asthma, King's College London, London, UK.
Division of Health and Social Care Research, King's College London, London, UK NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, London, UK.
Arch Dis Child Fetal Neonatal Ed. 2015 Jan;100(1):F35-8. doi: 10.1136/archdischild-2013-305817. Epub 2014 May 28.
To test the hypothesis that in very prematurely born infants remaining ventilated beyond the first week, proportional assist ventilation (PAV) compared with assist control ventilation (ACV) would be associated with reduced work of breathing, increased respiratory muscle strength and less ventilator-infant asynchrony which would be associated with improved oxygenation.
Randomised crossover study.
Tertiary neonatal unit.
12 infants with a median gestational age of 25 (range 24-26) weeks were studied at a median of 43 (range 8-86) days.
Infants were studied for 1 h each on PAV and ACV in random order.
At the end of each hour, the work of breathing (assessed by measuring the diaphragmatic pressure time product), thoracoabdominal asynchrony and respiratory muscle strength (maximal inspiratory pressure, maximal expiratory pressure (Pemax) and maximal transdiaphragmatic pressure (Pdimax)) were assessed. Blood gas analysis was performed and the oxygenation index (OI) calculated.
After 1 h on PAV compared with 1 h on ACV, the median OI (5.55 (range 5-11) vs 10.10 (range 7-16), p=0.002) and PTP levels were lower (217 (range 59-556) cm H2O.s/min vs 309 (range 55-544) cm H2O.s/min, p=0.005), while Pdimax (44.26 (range 21-66) cm H2O vs 37.9 (range 19-45) cm H2O, p=0.002) and Pemax (25.6 (range 6.5-42) cm H2O vs 15.9 (range 3-35) cm H2O levels p=0.010) were higher.
These results suggest that PAV compared with ACV may have physiological advantages for prematurely born infants who remain ventilated after the first week after birth.
验证以下假设：对于出生后第一周后仍需机械通气的极早产儿，与辅助控制通气（ACV）相比，比例辅助通气（PAV）可降低呼吸功，增强呼吸肌力量，减少呼吸机与婴儿之间的不同步，进而改善氧合。
随机交叉研究。
三级新生儿病房。
研究了12例中位胎龄为25周（范围24 - 26周）的婴儿，中位年龄为43天（范围8 - 86天）。
婴儿以随机顺序分别接受1小时的PAV和ACV治疗。
每小时结束时，评估呼吸功（通过测量膈肌压力时间乘积来评估）、胸腹不同步和呼吸肌力量（最大吸气压力、最大呼气压力（Pemax）和最大跨膈压（Pdimax））。进行血气分析并计算氧合指数（OI）。
与接受1小时ACV相比，接受1小时PAV后，中位OI（5.55（范围5 - 11）对10.10（范围7 - 16），p = 0.002）和PTP水平更低（217（范围59 - 556）cm H₂O·s/min对309（范围55 - 544）cm H₂O·s/min，p = 0.005），而Pdimax（44.26（范围21 - 66）cm H₂O对37.9（范围19 - 45）cm H₂O，p = 0.002）和Pemax水平更高（25.6（范围6.5 - 42）cm H₂O对15.9（范围3 - 35）cm H₂O，p = 0.010）。
这些结果表明，对于出生后第一周后仍需机械通气的极早产儿，与ACV相比，PAV可能具有生理优势。
