分级低氧对通过近红外光谱法测量的肝组织氧合的影响。

Effect of graded hypoxia on hepatic tissue oxygenation measured by near infrared spectroscopy.

作者信息

El-Desoky A E, Seifalian A M, Davidson B R

机构信息

University Department of Surgery, Royal Free Hospital Trust and Royal Free and University College School of Medicine, London, UK.

出版信息

J Hepatol. 1999 Jul;31(1):71-6. doi: 10.1016/s0168-8278(99)80165-2.

DOI:10.1016/s0168-8278(99)80165-2

PMID:10424285

Abstract

BACKGROUND/AIMS: In liver transplantation ischaemia-reperfusion injury of the graft reduces hepatic tissue oxygenation which has prognostic value for patient survival. Near infrared spectroscopy (NIRS) can measure extracellular (haemoglobin oxygenation) and intracellular tissue oxygenation (cytochrome oxidase oxidation). However, it has not been validated for measuring hepatic tissue oxygenation in an experimental model with graded hypoxia.

METHODS

New Zealand White rabbits (2.9+/-0.3 kg, n=9) underwent laparotomy for liver exposure. Heart rate, blood pressure, temperature, arterial blood pH and blood gas partial pressures were monitored during the experiments. Near infrared spectroscopy probes were placed on the liver surface to record continuously hepatic oxyhaemoglobin, deoxyhaemoglobin and cytochrome oxidase oxidation. Graded hypoxia was achieved by stepwise reduction of the inspired oxygen from 15 to 4%. During recovery from hypoxia 30% oxygen was administered.

RESULTS

There was an immediate reduction of hepatic oxyhaemoglobin with hypoxia and a simultaneous increase of hepatic deoxyhaemoglobin. Hepatic oxyhaemoglobin showed a positive correlation with arterial oxygen pressure (r=0.77, p<0.001). Hepatic deoxyhaemoglobin showed a negative correlation with arterial oxygen pressure (r=-0.75, p<0.001). Hepatic cytochrome oxidase decreased significantly with an inspired oxygen of 10% or less and showed a positive correlation with arterial oxygen pressure (r= 0.90, p<0.001).

CONCLUSIONS

Near infrared spectroscopy is an effective method for monitoring hepatic extracellular and intracellular tissue oxygenation.

摘要

背景/目的：在肝移植中，移植物的缺血再灌注损伤会降低肝组织氧合，这对患者生存具有预后价值。近红外光谱（NIRS）可测量细胞外（血红蛋白氧合）和细胞内组织氧合（细胞色素氧化酶氧化）。然而，在分级低氧的实验模型中，其尚未被验证用于测量肝组织氧合。

方法

新西兰白兔（2.9±0.3千克，n = 9）接受剖腹术以暴露肝脏。实验过程中监测心率、血压、体温、动脉血pH值和血气分压。将近红外光谱探头置于肝脏表面，以连续记录肝脏氧合血红蛋白（oxyhaemoglobin）、脱氧血红蛋白（deoxyhaemoglobin）和细胞色素氧化酶氧化情况。通过将吸入氧从15%逐步降至4%来实现分级低氧。在从低氧恢复过程中，给予30%的氧气。

结果

随着低氧出现，肝脏氧合血红蛋白立即减少，同时肝脏脱氧血红蛋白增加。肝脏氧合血红蛋白与动脉氧分压呈正相关（r = 0.77，p < 0.001）。肝脏脱氧血红蛋白与动脉氧分压呈负相关（r = -0.75，p < 0.001）。当吸入氧为10%或更低时，肝脏细胞色素氧化酶显著降低，且与动脉氧分压呈正相关（r = 0.90，p < 0.001）。