Tyszczuk L, Meek J, Elwell C, Wyatt J S
Department of Paediatrics, University College London School of Medicine, London, UK.
Pediatrics. 1998 Aug;102(2 Pt 1):337-41. doi: 10.1542/peds.102.2.337.
Preterm infants are often presumed to have a pressure passive cerebral circulation implying that a low mean arterial blood pressure (MABP) results in reduced cerebral perfusion. The aim of this study was to determine whether cerebral blood flow (CBF) was compromised in preterm infants whose MABP fell below 30 mm Hg (4 kPa).
Thirty preterm infants undergoing intensive care were studied within the first 24 hours of life. CBF was measured using near infrared spectroscopy. The infants were analyzed in two groups on the basis of their MABP at the time of study: group 1 had a MABP below 30 mm Hg and group 2 more than 30 mm Hg. CBF in the two groups was compared.
There was no significant difference in the mean CBF between the two groups. In group 1 the median MABP was 27.2 mm Hg (range, 23.7-29.9 mm Hg) and CBF was 13.9 (standard deviation, +/-6.9) mL . 100 g-1 . min-1. In group 2 the median MABP was 35.3 mm Hg (range, 30.1-39.3 mm Hg) and CBF was 12.3 (standard deviation, +/-6.4) mL . 100 g-1 . min-1. Mortality and incidence of cranial ultrasound scan abnormalities were also not significantly different.
These results indicate that preterm infants undergoing intensive care are able to maintain adequate cerebral perfusion at a MABP in the range of 23.7 to 39.3 mm Hg.
早产儿通常被认为具有压力被动性脑循环，这意味着低平均动脉血压（MABP）会导致脑灌注减少。本研究的目的是确定MABP降至30毫米汞柱（4千帕）以下的早产儿的脑血流量（CBF）是否受到影响。
对30名接受重症监护的早产儿在出生后的头24小时内进行研究。使用近红外光谱法测量CBF。根据研究时的MABP将婴儿分为两组：第1组MABP低于30毫米汞柱，第2组高于30毫米汞柱。比较两组的CBF。
两组的平均CBF无显著差异。第1组的MABP中位数为27.2毫米汞柱（范围为23.7 - 29.9毫米汞柱），CBF为13.9（标准差，±6.9）毫升·100克⁻¹·分钟⁻¹。第2组的MABP中位数为35.3毫米汞柱（范围为30.1 - 39.3毫米汞柱），CBF为12.3（标准差，±6.4）毫升·100克⁻¹·分钟⁻¹。头颅超声扫描异常的死亡率和发生率也无显著差异。
这些结果表明，接受重症监护的早产儿在MABP为23.7至39.3毫米汞柱的范围内能够维持足够的脑灌注。
