采用氧敏感多丝电极测定猪左心室表面组织氧分压。

Conzen P F, Habazettl H, Christ M, Baier H, Hobbhahn J, Vollmar B, Peter K

University of Munich, Germany.

Cardiovasc Res. 1991 Mar;25(3):207-16. doi: 10.1093/cvr/25.3.207.

STUDY OBJECTIVE

Polarographic oxygen sensitive electrodes can be used to measure tissue oxygen pressures on the surface of the beating heart. The purpose of the study was to clarify the significance of these PO2 determinations.

DESIGN

Changes in left ventricular surface oxygen pressures, subendocardial or subepicardial wall functions (ultrasonic dimension technique), and blood flow (radioactive microsphere technique) were correlated during different degrees of acute coronary artery stenoses in pigs.

EXPERIMENTAL MATERIAL

19 anaesthetised open chest pigs, 28-40 kg body weight, were studied during different degrees of constriction of the left anterior descending artery which did not influence overall left ventricular function or irreversibly damage the myocardium.

MEASUREMENTS AND MAIN RESULTS

Highly significant (p less than 0.001) correlations (each % delta) were obtained for surface tissue oxygen pressures (y) with subepicardial (y = 0.002 e 0.10x; r = 0.89) and subendocardial (y = 1.44 e 0.04x; r = 0.98) blood flow values, as well as with subendocardial function (y = 82.4 + 0.22x; r = 0.89); a significant correlation was also obtained for subendocardial function (y) with subendocardial blood flow (y = 66.0 + 0.28x; r = 0.69). However, no significant correlation was obtained for polarographic tissue PO2 with subepicardial segment function, indicating that regional function was maintained when tissue PO2 recordings were not much above 0 kPa and when blood flow was reduced by 25 to 30%.

CONCLUSIONS

Oxygen pressures of the superficial layers of the left ventricle are relatively high at normal values of oxygen consumption but decrease rapidly if blood supply is reduced. Regional wall function is preserved at low oxygen pressures. Polarographic surface PO2 electrodes hence can be used to study influences of experimental interventions on oxygenation of the normally perfused and of the moderately ischaemic myocardium.

研究目的

极谱氧敏感电极可用于测量跳动心脏表面的组织氧分压。本研究的目的是阐明这些氧分压测定的意义。

设计

在猪不同程度的急性冠状动脉狭窄过程中，对左心室表面氧分压、心内膜下或心外膜下壁功能（超声尺寸技术）和血流（放射性微球技术）的变化进行相关性分析。

实验材料

对19只体重28 - 40千克的麻醉开胸猪进行研究，在左前降支动脉不同程度的缩窄过程中，其不影响左心室整体功能或不可逆地损伤心肌。

测量与主要结果

表面组织氧分压（y）与心外膜下（y = 0.002 e 0.10x；r = 0.89）和心内膜下（y = 1.44 e 0.04x；r = 0.98）血流值以及心内膜下功能（y = 82.4 + 0.22x；r = 0.89）之间获得了高度显著（p < 0.001）的相关性（各%变化）；心内膜下功能（y）与心内膜下血流（y = 66.0 + 0.28x；r = 0.69）之间也获得了显著相关性。然而，极谱组织氧分压与心外膜下节段功能之间未获得显著相关性，表明当组织氧分压记录不高于0 kPa且血流减少25%至30%时，区域功能得以维持。