新生羔羊窒息后的脑血流量和氧代谢

Cerebral blood flow and O2 metabolism after asphyxia in neonatal lambs.

作者信息

Rosenberg A A

出版信息

Pediatr Res. 1986 Aug;20(8):778-82. doi: 10.1203/00006450-198608000-00016.

DOI:10.1203/00006450-198608000-00016

Abstract

A neonatal lamb model has been developed to examine the regulation of cerebral blood flow (CBF) and oxygen metabolism during the critical period after an asphyxial insult. Nine newborn lambs had control measurements and timed measurements after asphyxia of CBF (radioactive microsphere technique), arterial and cerebral venous (sagittal sinus) blood gases and oxygen contents performed. Immediately after resuscitation from asphyxia, there was a marked increase in CBF compared to control (239 +/- 22 versus 82 +/- 7 ml X 100 g-1 X min-1, mean +/- SEM; p less than 0.01). Cerebral oxygen delivery (CBF X arterial O2 content) increased from 12.87 +/- 1.20 to 37.40 +/- 3.40 ml X 100 g-1 X min-1 (p less than 0.01), while cerebral O2 consumption was significantly decreased compared to control (4.75 +/- 0.42 to 3.42 +/- 0.46 ml X 100 g-1 X min-1, p less than 0.05). Cerebral fractional O2 extraction, the relationship between oxygen uptake and delivery fell from 0.38 +/- 0.03 to 0.09 +/- 0.02; p less than 0.01. This reactive hyperemia was followed in all animals by a period of hypoperfusion. CBF (52 +/- 4 ml X 100 g-1 X min-1), O2 delivery (7.94 +/- 0.50 ml X 100 g-1 X min-1), and cerebral O2 consumption (3.34 +/- 0.24 ml X 100 g-1 X min-1) were all significantly depressed when compared to control. These data demonstrate important changes in CBF and O2 metabolism after neonatal asphyxia that may be important to the pathogenesis of brain injury.

摘要

已建立一种新生羔羊模型，用于研究窒息性损伤后关键时期脑血流量（CBF）和氧代谢的调节。对9只新生羔羊进行了对照测量，并在窒息后对CBF（放射性微球技术）、动脉血和脑静脉（矢状窦）血气及氧含量进行了定时测量。窒息复苏后即刻，与对照相比CBF显著增加（239±22对82±7 ml·100 g⁻¹·min⁻¹，均值±标准误；p＜0.01）。脑氧输送（CBF×动脉血氧含量）从12.87±1.20增加至37.40±3.40 ml·100 g⁻¹·min⁻¹（p＜0.01），而脑氧消耗与对照相比显著降低（4.75±0.42至3.42±0.46 ml·100 g⁻¹·min⁻¹，p＜0.05）。脑氧摄取分数，即氧摄取与输送的关系从0.38±0.03降至0.09±0.02；p＜0.01。所有动物在这种反应性充血后都经历了一段灌注不足期。与对照相比，CBF（52±4 ml·100 g⁻¹·min⁻¹）、氧输送（7.94±0.50 ml·100 g⁻¹·min⁻¹）和脑氧消耗（3.34±0.24 ml·100 g⁻¹·min⁻¹）均显著降低。这些数据表明新生窒息后脑血流量和氧代谢发生了重要变化，这可能对脑损伤的发病机制具有重要意义。