在逆行性脑灌注期间采用pH稳态策略可改善脑灌注和组织氧合。

Use of a pH-stat strategy during retrograde cerebral perfusion improves cerebral perfusion and tissue oxygenation.

作者信息

Ye Jian, Li Zhijun, Yang Yanmin, Yang Luojia, Turner Allan, Jackson Michael, Deslauriers Roxanne

机构信息

Department of Surgery, University of Manitoba, Winnipeg, Canada.

出版信息

Ann Thorac Surg. 2004 May;77(5):1664-70; discussion 1670. doi: 10.1016/j.athoracsur.2003.10.005.

DOI:10.1016/j.athoracsur.2003.10.005

PMID:15111162

Abstract

BACKGROUND

Although it is well documented that the use of a pH-stat strategy during hypothermic cardiopulmonary bypass improves cerebral blood flow, an alpha-stat strategy has been almost exclusively used during retrograde cerebral perfusion. We investigated the effects of pH-stat and alpha-stat management on brain tissue blood flow and oxygenation during retrograde cerebral perfusion in a porcine model to determine if the use of a pH-stat strategy during retrograde cerebral perfusion improves brain tissue perfusion.

METHODS

Fourteen pigs were managed by an alpha-stat strategy (alpha-stat group, n = 7) or by a pH-stat strategy (pH-stat group, n = 7) during 120 minutes of hypothermic retrograde cerebral perfusion. Retrograde cerebral perfusion was established through the superior vena cava. Brain tissue blood flow and oxygenation were measured continuously with a laser flowmeter and near infrared spectroscopy, respectively. Brain tissue water content was determined at the end of the experiments.

RESULTS

During cooling, brain tissue blood flow was significantly higher with use of the pH-stat strategy than with the alpha-stat strategy (86% +/- 10% versus 40% +/- 3% of baseline). During retrograde cerebral perfusion, brain tissue blood flow was also significantly higher (about three times higher) in the pH-stat group than in the alpha-stat group (15% +/- 4% versus 5% +/- 1% of baseline at 60 minutes of retrograde cerebral perfusion). Tissue oxygen saturation appeared to be higher during retrograde cerebral perfusion in the pH-stat group than in the alpha-stat group. Brain tissue blood flow during rewarming remained significantly higher with the use of pH-stat than with the use of alpha-stat. Brain tissue water contents were similar in both groups.

CONCLUSIONS

In our pig model, the use of a pH-stat strategy during retrograde cerebral perfusion significantly improves brain tissue perfusion. Therefore, to improve retrograde cerebral blood flow during retrograde cerebral perfusion, it may be preferable to use a pH-stat strategy, rather than an alpha-stat strategy.

摘要

背景

尽管有充分的文献记载，在低温体外循环期间采用pH稳态策略可改善脑血流量，但在逆行脑灌注期间几乎一直采用α稳态策略。我们在猪模型中研究了pH稳态和α稳态管理对逆行脑灌注期间脑组织血流和氧合的影响，以确定在逆行脑灌注期间使用pH稳态策略是否能改善脑组织灌注。

方法

14头猪在120分钟的低温逆行脑灌注期间采用α稳态策略（α稳态组，n = 7）或pH稳态策略（pH稳态组，n = 7）进行管理。通过上腔静脉建立逆行脑灌注。分别用激光流量计和近红外光谱仪连续测量脑组织血流和氧合。在实验结束时测定脑组织含水量。

结果

在降温过程中，采用pH稳态策略时脑组织血流明显高于采用α稳态策略时（分别为基线的86%±10%和40%±3%）。在逆行脑灌注期间，pH稳态组的脑组织血流也明显高于α稳态组（约高三倍）（逆行脑灌注60分钟时分别为基线的15%±4%和5%±1%）。pH稳态组在逆行脑灌注期间的组织氧饱和度似乎高于α稳态组。复温期间，采用pH稳态时的脑组织血流仍明显高于采用α稳态时。两组的脑组织含水量相似。