Gharagozloo F, Bulkley G B, LaFrance N, Zuidema G D
J Surg Res. 1983 Jun;34(6):581-8. doi: 10.1016/0022-4804(83)90114-2.
Significant delay in the washout of intraperitoneal xenon (133Xe) in rats and dogs with decreased splanchnic blood flow (bowel strangulation, superior mesenteric artery and vein occlusion) has been previously demonstrated as the basis for radionuclide imaging to detect early (prenecrotic) intestinal ischemia. In this study, the effect of ascites, adhesions, and misdirected injections on the validity of this technique is evaluated. Xenon-133 (0.6 mCi) in 3 ml saline was injected into the peritoneal cavity of anesthetized rats and the washout of gamma activity monitored externally for 90 min. Gamma camera images were obtained at 30-min intervals. After 60 min, only 12 +/- 2% of injected activity remained in the controls. Sham operation (13 +/- 1%) and simple obstruction (12 +/- 2%) had been previously shown not to significantly slow washout, but segmental strangulation had done so dramatically (32 +/- 2%, P less than 0.0001). In these experiments, ascitic fluid (Ringer's lactate) in volumes of 10 ml (13 +/- 1%), 20 ml (13 +/- 1%), and 40 ml (13 +/- 1%), did not significantly slow washout in nonischemic rats. Sixty and eighty milliliters produced very tense ascites and slight but significant delay in washout (14 +/- 1%, 17 +/- 1%, respectively, P less than 0.05). Moderate (11 +/- 1%) and severe (11 +/- 1%) adhesions produced by serosal scarification did not delay washout nor affect imaging. Injections of isotope intentionally misdirected into the abdominal wall (32 +/- 2%), bowel wall (18 +/- 1%), and bowel lumen (19 +/- 2%), each significantly (P less than 0.001) slowed washout. However, such misdirected injections were easily recognizable as such on the 1-min gamma camera images and could thereby be excluded as artifactual. Therefore, no false positive readings were obtained. It is concluded that the intraperitoneal xenon technique is not invalidated by mild to moderate ascites nor by moderate to severe adhesions. Misdirected injections produce invalid studies that are recognizable as such and thus are not misinterpreted. This approach should therefore be applicable to most patients with suspected intestinal ischemia.
先前已证实，在内脏血流减少（肠绞窄、肠系膜上动静脉闭塞）的大鼠和狗中，腹腔内氙（133Xe）清除出现显著延迟，这是放射性核素成像检测早期（坏死前）肠道缺血的基础。在本研究中，评估了腹水、粘连和注射位置不当对该技术有效性的影响。将3ml生理盐水中的0.6mCi 133Xe注入麻醉大鼠的腹腔，并在外部监测γ活性清除90分钟。每隔30分钟获取γ相机图像。60分钟后，对照组中仅留存12±2%的注入活性。先前已表明，假手术（13±1%）和单纯梗阻（12±2%）不会显著减慢清除速度，但节段性绞窄会显著减慢（32±2%，P<0.0001）。在这些实验中，10ml（13±1%）、20ml（13±1%）和40ml（13±1%）的腹水（乳酸林格液）在非缺血大鼠中并未显著减慢清除速度。60ml和80ml会产生非常紧张的腹水，并导致清除略有但显著延迟（分别为14±1%、17±1%，P<0.05）。浆膜划痕造成的中度（11±1%）和重度（11±1%）粘连并未延迟清除，也未影响成像。故意将同位素注入腹壁（32±2%）、肠壁（18±1%）和肠腔（19±2%），均显著（P<0.001）减慢清除速度。然而，这种注射位置不当在1分钟的γ相机图像上很容易识别，因此可将其作为假象排除。因此，未获得假阳性读数。结论是，轻度至中度腹水和中度至重度粘连不会使腹腔内氙技术无效。注射位置不当会导致无效研究，且可识别，因此不会被误判。因此，这种方法应适用于大多数疑似肠道缺血的患者。
