Gawad K A, Wachowiak R, Rempf C, Tiefenbacher W J, Strate T, Achilles E G, Blöchle C, Izbicki J R
Department of Surgery, University Hospital Hamburg-Eppendorf, University of Hamburg, Martinstr. 52, D-20246 Hamburg, Germany.
Surg Endosc. 2003 Oct;17(10):1556-60. doi: 10.1007/s00464-002-9245-4. Epub 2003 Aug 15.
pH monitoring has been established as the "gold standard" in the diagnosis of gastroesophageal reflux. Evaluation of experimental antireflux therapy should therefore also include this technique, but a suitable technique in an experimental model did not exist so far. The aim of our study was to establish a reliable method for the evaluation of an experimental reflux model in pigs.
A total of 33 German Landrace pigs with an average body weight of 56 (50.2-67.2) kg were included. pH monitoring was performed before and after open cardiomyotomy in each animal. All manipulations were performed under general anesthesia. After manometric localization of the gastroesophageal high-pressure zone, a standard pH probe was inserted into the pharynx through a small needle-punctured canal on the side of the animal's snout and placed under endoscopic guidance with the proximal sensor 3 cm above the lower esophageal sphincter (LES) and the distal sensor in the stomach for reference. The harness to carry the pH recorder on the animal's back consisted of a modified belly strap that enabled the animal to move around without limitation. For analysis the same threshold levels were defined as in humans. Gastroesophageal reflux was induced by cardiomyotomy.
The placement of the standard pH probe was possible in all cases. Inserting the probe on the side of the snout left the animals free to nuzzle, which complies with the normal habits of pigs, without breaking the probes and without being compromised in their natural behavior. Repeated punctures for multiple measurements were easily feasible. We performed up to three examinations in each individual animal. Recording was performed for 48 h. A mean number of 67.3 (+/-9.7) acidic refluxes were registered. The mean number of long acidic refluxes was 3.2 (+/-0.75). For an average total time of 75.5 (+/-14.3) min the pH was below 4 accounting for a fraction time pH below 4 of 3.5% (+/-0.68%). Following cardiomyotomy the number of acidic refluxes increased significantly to 166.1 (+/-21.8) and the number of long refluxes to 17.74 (+/-3.35). The total time of pH below 4 increased to 371.3 (+/-62) min so that the fraction time pH below 4 was 14.5% ( p = 0.0006).
pH monitoring should be mandatory in any investigation of antireflux therapy. Our method is easy and secure to perform. It is suitable for other gastrointestinal investigations (Bilitec, long-term manometry) that could be carried out using the same technique. The described data represent the basis for other investigations of experimental antireflux therapy.
pH监测已被确立为胃食管反流诊断的“金标准”。因此，实验性抗反流治疗的评估也应包括该技术，但迄今为止在实验模型中尚无合适的技术。我们研究的目的是建立一种可靠的方法来评估猪的实验性反流模型。
共纳入33头德国长白猪，平均体重56（50.2 - 67.2）kg。对每只动物在开胸心肌切开术前和术后进行pH监测。所有操作均在全身麻醉下进行。在测压定位胃食管高压区后，通过动物口鼻一侧的小针穿刺通道将标准pH探头插入咽部，并在内镜引导下放置，使近端传感器位于食管下括约肌（LES）上方3 cm处，远端传感器置于胃内作为参考。动物背部携带pH记录仪的背带由改良的腹带组成，使动物能够不受限制地活动。分析时使用与人类相同的阈值水平。通过心肌切开术诱发胃食管反流。
所有病例均能成功放置标准pH探头。将探头插在口鼻一侧使动物能够自由拱鼻，这符合猪的正常习性，不会损坏探头且不影响其自然行为。多次穿刺进行多次测量很容易实现。我们对每只动物最多进行了三次检查。记录时间为48小时。平均记录到67.3（±9.7）次酸性反流。长时间酸性反流的平均次数为3.2（±0.75）次。pH低于4的平均总时间为75.5（±14.3）分钟，占pH低于4的时间分数为3.5%（±0.68%）。心肌切开术后，酸性反流次数显著增加至166.1（±21.8）次，长时间反流次数增加至17.74（±3.35）次。pH低于4的总时间增加至371.3（±62）分钟，使pH低于4的时间分数为14.5%（p = 0.0006）。
在任何抗反流治疗研究中，pH监测都应是必需的。我们的方法操作简便且安全。它适用于其他可使用相同技术进行的胃肠道研究（Bilitec、长期测压）。所描述的数据为实验性抗反流治疗的其他研究奠定了基础。
