Nguyen Nam Q, Tippett Marcus, Smout Andre J P M, Holloway Richard H
Department of Gastroenterology, Hepatology and General Medicine, Royal Adelaide Hospital and University of Adelaide, Adelaide, South Australia, Australia.
Am J Gastroenterol. 2006 Nov;101(11):2476-84. doi: 10.1111/j.1572-0241.2006.00796.x. Epub 2006 Oct 4.
Esophageal wave amplitude is an important determinant of esophageal clearance. A threshold of 30 mmHg is widely accepted as the threshold for effective clearance in the distal esophagus. However, the precise relationship between wave amplitude and clearance has received relatively little attention. The aim of this study was to assess the impact of peristaltic wave amplitude on esophageal volume clearance using multiple intraluminal impedance (MII) measurement.
Concurrent manometry and MII were performed on 42 healthy asymptomatic volunteers and 13 patients with ineffective esophageal motility. Esophageal motility was measured at four sites 5-cm apart, starting 2 cm above the lower esophageal sphincter. MII was measured at corresponding sites with electrodes incorporated into the manometric assembly. Ten 5-mL liquid (saline) boluses and ten 5-mL low impedance viscous boluses were tested in each subject. Pressure wave amplitude was determined at each site as well as peristaltic success of the responses. Bolus clearance was measured from individual recording segment and from the esophagus as a whole.
The proportion of liquid boluses cleared at each site was directly related to wave amplitude and did not increase significantly above a threshold of 25 mmHg in the proximal esophagus, 22 mmHg in the mid-esophagus, and 30 mmHg in the distal esophagus. Corresponding wave amplitudes for total esophageal clearance were 35-40 mmHg. There was a good correlation between the wave amplitude at one site of the esophagus and those of the rest of the esophagus. For both liquid and viscous boluses, the likelihood of impaired clearance was directly related to the number of segments with hypotensive pressure waves.
The findings confirm the validity of the wave amplitude threshold required for effective liquid bolus clearance and have established the amplitude threshold for clearance of viscous boluses. However, the number of hypotensive pressure waves required for the definition of ineffective motility may be too low.
食管波幅是食管清除功能的重要决定因素。30 mmHg的阈值被广泛认为是食管远端有效清除的阈值。然而，波幅与清除功能之间的确切关系相对较少受到关注。本研究的目的是使用多通道腔内阻抗（MII）测量来评估蠕动波幅对食管容积清除的影响。
对42名健康无症状志愿者和13名食管动力障碍患者同时进行测压和MII检查。从食管下括约肌上方2 cm处开始，在相距5 cm的四个部位测量食管动力。通过将电极整合到测压装置中，在相应部位测量MII。在每个受试者中测试10次5 mL液体（盐水）团注和10次5 mL低阻抗粘性团注。确定每个部位的压力波幅以及反应的蠕动成功率。从各个记录段以及整个食管测量团注清除情况。
每个部位清除的液体团注比例与波幅直接相关，在食管近端波幅超过25 mmHg、食管中段超过22 mmHg、食管远端超过30 mmHg时，清除比例没有显著增加。食管总清除的相应波幅为35 - 40 mmHg。食管一个部位的波幅与食管其他部位的波幅之间存在良好的相关性。对于液体和粘性团注，清除受损的可能性与出现低血压压力波的节段数量直接相关。
研究结果证实了有效液体团注清除所需波幅阈值的有效性，并确定了粘性团注清除的波幅阈值。然而，用于定义动力障碍的低血压压力波数量可能过低。
