Rhee Christopher J, Kaiser Jeffrey R, Rios Danielle R, Kibler Kathleen K, Easley R Blaine, Andropoulos Dean B, Czosnyka Marek, Smielewski Peter, Varsos Georgios V, Rusin Craig G, Gauss C Heath, Williams D Keith, Brady Ken M
Section of Neonatology, Department of Pediatrics, Texas Children's Hospital/Baylor College of Medicine, Houston, TX.
Section of Neonatology, Department of Pediatrics, Texas Children's Hospital/Baylor College of Medicine, Houston, TX; Department of Obstetrics and Gynecology, Texas Children's Hospital/Baylor College of Medicine, Houston, TX.
J Pediatr. 2016 Jul;174:52-6. doi: 10.1016/j.jpeds.2016.03.066. Epub 2016 Apr 23.
To determine whether the diastolic closing margin (DCM), defined as diastolic blood pressure minus critical closing pressure, is associated with the development of early severe intraventricular hemorrhage (IVH).
A reanalysis of prospectively collected data was conducted. Premature infants (gestational age 23-31 weeks) receiving mechanical ventilation (n = 185) had ∼1-hour continuous recordings of umbilical arterial blood pressure, middle cerebral artery cerebral blood flow velocity, and PaCO2 during the first week of life. Models using multivariate generalized linear regression and purposeful selection were used to determine associations with severe IVH.
Severe IVH (grades 3-4) was observed in 14.6% of the infants. Irrespective of the model used, Apgar score at 5 minutes and DCM were significantly associated with severe IVH. A clinically relevant 5-mm Hg increase in DCM was associated with a 1.83- to 1.89-fold increased odds of developing severe IVH.
Elevated DCM was associated with severe IVH, consistent with previous animal data showing that IVH is associated with hyperperfusion. Measurement of DCM may be more useful than blood pressure in defining cerebral perfusion in premature infants.
确定舒张期关闭压差（定义为舒张压减去临界关闭压）是否与早期严重脑室内出血（IVH）的发生有关。
对前瞻性收集的数据进行重新分析。纳入185例接受机械通气的早产儿（胎龄23 - 31周），在出生后第一周连续记录约1小时的脐动脉血压、大脑中动脉脑血流速度和动脉血二氧化碳分压（PaCO₂）。使用多变量广义线性回归模型和有目的的选择方法来确定与严重IVH的关联。
14.6%的婴儿发生了严重IVH（3 - 4级）。无论使用何种模型，5分钟时的阿氏评分和舒张期关闭压差均与严重IVH显著相关。舒张期关闭压差临床上相关的5 mmHg升高与发生严重IVH的几率增加1.83至1.89倍相关。
舒张期关闭压差升高与严重IVH相关，这与之前动物数据显示IVH与高灌注有关一致。在定义早产儿脑灌注方面，测量舒张期关闭压差可能比血压更有用。
