Antonsson J B, Haglund U H
Department of Surgery, University Hospital, Uppsala, Sweden.
Gut. 1995 Dec;37(6):791-7. doi: 10.1136/gut.37.6.791.
The tonometric method of detecting decreased gut intramucosal pH (pHi) is based on the fact that carbon dioxide can diffuse through the wall of the silastic balloon of the tonometer. By using deoxified saline and measuring PO2 as well as PCO2 this study aimed to follow changes in mucosal PO2 and relate them to changes in pHi in peritonitis versus haemorrhage. Twenty five pigs were used. Five were controls, in 10 peritonitis was induced by the instillation of faeces in the abdominal cavity, and 10 were bled, half of them stepwise during three hours, and half of them rapidly down to a mean (SEM) arterial pressure of 30 (10) mm Hg. The drop in pHi correlated well with decreasing intraluminal PO2 (r = 0.63 (0.13)) in haemorrhage. In peritonitis this drop occurred within a very limited change in intraluminal PO2 (r = 0.06 (0.17)). Thus oxygen seemed to be present in the mucosa at the same time as there were signs of anaerobic metabolism as evidenced by a low intramucosal pH. Impaired oxygen extraction or utilisation, or both, is proposed as an explanation to this seemingly paradoxical situation.
检测肠道黏膜内pH值（pHi）降低的眼压测量法基于这样一个事实，即二氧化碳能够扩散通过眼压计硅胶球囊壁。本研究通过使用脱氧盐水并测量PO2以及PCO2，旨在追踪黏膜PO2的变化，并将其与腹膜炎和出血时pHi的变化相关联。使用了25头猪。5头为对照组，10头通过向腹腔内注入粪便诱导腹膜炎，10头进行放血，其中一半在3小时内逐步放血，另一半迅速放血至平均（标准误）动脉压为30（10）mmHg。在出血时，pHi的下降与腔内PO2的降低密切相关（r = 0.63（0.13））。在腹膜炎时，这种下降发生在腔内PO2变化非常有限的情况下（r = 0.06（0.17））。因此，在黏膜内pH值较低表明存在无氧代谢迹象的同时，黏膜中似乎仍存在氧气。氧摄取或利用受损，或两者皆有，被认为是对这种看似矛盾情况的一种解释。
