Pitt K A, Mayhew P D, Barter L, Pollard R, Kass P H, Marks S L
From the Departments of Surgical and Radiological Sciences.
Population Health and Reproduction.
Dis Esophagus. 2017 Apr 1;30(4):1-7. doi: 10.1093/dote/dow031.
The EndoFLIP (Endolumenal Functional Lumen Imaging Probe, Crospon Inc, Galway, Ireland) device uses the technique of impedance planimetry to evaluate dimensions and distensibility of the upper and lower esophageal sphincter. The null hypotheses for this study were that EndoFLIP variables would be stable between anesthestic episodes and would not be affected by body position when evaluating the upper and lower esophageal sphincters in healthy dogs. During each of three consecutive general anesthesia episodes administered to eight healthy adult research colony dogs with a standardized protocol, the EndoFLIP catheter was positioned to measure cross-sectional area, intrabag pressure, upper and lower esophageal sphincter length at two different balloon fill volumes (30 and 40 mL) and two body positions (lateral and dorsal recumbency). From these measured variables, a distensibility index was also calculated. Mixed effect analysis of variance was used to evaluate the fixed marginal and interaction effects of anesthesia episode, body position, and balloon volume on measured and calculated variables. For the upper esophageal sphincter significant interactions were present between anesthetic episode and body position for all variables except intrabag pressure; adjusting for body position significant differences were present between anesthetic episodes for all variables except distensibility index; adjusting for anesthetic episode cross-sectional area, intrabag pressure, upper esophageal sphincter length and distensibility index were all affected by body position. For the lower esophageal sphincter distensibility index was the only variable where a significant interaction between anesthesia episode and body position occurred; cross-sectional area, intrabag pressure, and lower esophageal length were not significantly affected by anesthesia episode when adjusting for body position; distensibility index was the only variable significantly affected by body position. Measurements of the geometry of the lower esophageal sphincter as measured by the EndoFLIP device were consistent under conditions of general anesthesia. Similar measurements taken at the upper esophageal sphincter displayed greater variability between anesthetic episodes and were affected to a greater extent by body position. Body position should be standardized in studies using the EndoFLIP to assess geometric and functional characteristics of the upper and lower esophageal sphincters.
EndoFLIP（腔内功能性管腔成像探头，克罗斯彭公司，爱尔兰戈尔韦）设备采用阻抗平面测量技术来评估食管上、下括约肌的尺寸和扩张性。本研究的无效假设是，在评估健康犬的食管上、下括约肌时，EndoFLIP变量在麻醉期间是稳定的，且不受体位影响。在按照标准化方案对8只健康成年实验犬连续进行的三次全身麻醉过程中，将EndoFLIP导管放置在两个不同的球囊充盈体积（30和40 mL）和两个体位（侧卧和仰卧）下，测量食管上、下括约肌的横截面积、球囊内压力、长度，并计算扩张指数。采用混合效应方差分析来评估麻醉次数、体位和球囊体积对测量和计算变量的固定边际效应和交互效应。对于食管上括约肌，除球囊内压力外，所有变量在麻醉次数和体位之间均存在显著交互作用；在校正体位后，除扩张指数外，所有变量在不同麻醉次数之间均存在显著差异；在校正麻醉次数后，横截面积、球囊内压力、食管上括约肌长度和扩张指数均受体位影响。对于食管下括约肌，扩张指数是唯一在麻醉次数和体位之间存在显著交互作用的变量；在校正体位后，横截面积、球囊内压力和食管下括约肌长度不受麻醉次数显著影响；扩张指数是唯一受体位显著影响的变量。在全身麻醉条件下，通过EndoFLIP设备测量的食管下括约肌几何形状的测量结果是一致的。在食管上括约肌进行的类似测量在不同麻醉次数之间显示出更大的变异性，并且受体位影响更大。在使用EndoFLIP评估食管上、下括约肌的几何和功能特征的研究中，应标准化体位。
