在猪脑损伤模型中，液体平衡和钠给药与脑水肿形成及颅内压的关系。

The relationship of fluid balance and sodium administration to cerebral edema formation and intracranial pressure in a porcine model of brain injury.

作者信息

Ramming S, Shackford S R, Zhuang J, Schmoker J D

机构信息

Department of Surgery, University of Vermont, College of Medicine, Burlington.

出版信息

J Trauma. 1994 Nov;37(5):705-13. doi: 10.1097/00005373-199411000-00003.

DOI:10.1097/00005373-199411000-00003

PMID:7966466

Abstract

BACKGROUND

Fluid and sodium restriction have been advocated after brain injury as a means of controlling intracranial pressure (ICP). Recent clinical data showing no significant relationships between the amount of fluid infused or sodium administered (Na) and ICP question this practice.

OBJECTIVE

To analyze the relationship of amount of fluid, Na, and fluid balance to cerebral edema formation and ICP.

METHODS

A cryogenic brain injury with and without hemorrhagic shock was studied after 24 hours in swine (n = 35) randomized to receive either lactated Ringer's solution (LR) or hypertonic sodium lactate (HSL). Cerebral edema formation as indicated by cortical water content (CWC) was determined by measurement of specific gravity.

RESULTS

There was a significant positive correlation between the following variables: (1) amount of fluid and ICP (r = 0.598; p < 0.01); (2) fluid balance and ICP (r = 0.684; p < 0.01); and (3) free water and ICP (r = 0.614; p < 0.01). There was a significant negative correlation between serum osmolarity and ICP (r = -0.654; p < 0.01). The study failed to demonstrate a significant correlation between Na and ICP, amount of fluid and CWC, or fluid balance and CWC.

CONCLUSIONS

These data suggest that both the volume of fluid infused and the fluid balance do affect the ICP, but the amount of Na infused does not. The lack of a significant correlation between any of the independent variables and CWC suggests that their effect on ICP is not related to cerebral edema formation. These findings, combined with the observed significant positive correlation between free H2O infused and ICP, and the significant negative correlation between serum osmolarity and ICP, suggest that HSL resuscitation increases intracranial compliance after brain injury while LR decreases it. The data also suggest that free water restriction is warranted in patients with head injuries.

摘要

背景

脑损伤后一直提倡限制液体和钠的摄入，以此作为控制颅内压（ICP）的一种方法。近期临床数据表明，输入的液体量或给予的钠量（Na）与颅内压之间并无显著关联，这对该做法提出了质疑。

目的

分析液体量、钠、液体平衡与脑水肿形成及颅内压之间的关系。

方法

对35头猪进行研究，通过随机分组使其接受乳酸林格氏液（LR）或高渗乳酸钠（HSL），在24小时后对伴有和不伴有失血性休克的低温脑损伤进行研究。通过测量比重来确定以皮质含水量（CWC）表示的脑水肿形成情况。

结果

以下变量之间存在显著正相关：（1）液体量与颅内压（r = 0.598；p < 0.01）；（2）液体平衡与颅内压（r = 0.684；p < 0.01）；（3）游离水与颅内压（r = 0.614；p < 0.01）。血清渗透压与颅内压之间存在显著负相关（r = -0.654；p < 0.01）。该研究未能证明钠与颅内压、液体量与皮质含水量或液体平衡与皮质含水量之间存在显著相关性。

结论

这些数据表明，输入的液体量和液体平衡确实会影响颅内压，但输入的钠量则不会。任何自变量与皮质含水量之间均缺乏显著相关性，这表明它们对颅内压的影响与脑水肿形成无关。这些发现，再加上观察到输入的游离水与颅内压之间存在显著正相关，以及血清渗透压与颅内压之间存在显著负相关，表明高渗乳酸钠复苏可增加脑损伤后的颅内顺应性，而乳酸林格氏液则会降低颅内顺应性。数据还表明，对于头部受伤患者，限制游离水是必要的。