正常人和胃食管反流病人的昼夜食管pH和动力变化

目的:为探讨正常人和胃食管反流病(gastroesophageal reflux disease,GERD)病人昼夜食管运动规律以及食管运动与酸反流的关系。方法:45例GERD病人和10名正常人均接受食管测压和动态食管pH及压力同步监测。结果:(1)下食管括约肌压、远端食管蠕动压及有效食管蠕动百分比在酸反流DeMeester高计分组明显低于低计分组(P<0.05),在反流性食管炎组也明显低于非反流性食管炎组(P<0.05)。(2)有GERD症状或食管炎的卧位有效蠕动百分比明显低于立位(P<0.05)。反流性食管炎组80％有夜间或伴有夜间反流,而不伴反流性食管炎的GERD无1例出现夜间反流。结论:昼夜食管pH和压力动态监测有利于进一步探讨GERD的运动病理,除LES功能外,食管清除功能在GERD发病中起重要作用。     

Inclusion of supine period in short-duration pH monitoring is essential in diagnosis of gastroesophageal reflux disease

Prolonged esophageal pH monitoring is the most accurate method for detecting abnormal gastroesophageal reflux (GER) in patients with gastroesophageal reflux disease (GERD). However, some investigators have found that short-duration postprandial pH monitoring in the upright position is also useful, while others have failed to find such results. Therefore, we have compared a 6-hr period of pH monitoring (3-hr postprandial period after daytime meal and 3-hr supine period) with a total 24-hr period in detecting abnormal gastroesophageal reflux. Sixty-five patients (44 men, mean age 41.3 years) with GERD and 16 healthy volunteers (11 men, mean age 34.3 years) underwent 24-hr pH monitoring according to a standard protocol. Various reflux parameters during 24-hr pH monitoring were compared with reflux parameters during the 6-hr period. Abnormal GER was detected in 56 patients presenting with typical symptoms of GERD (sensitivity 86.2%). These patients could be further divided into upright (N=18), supine (N=15), and combined (N=23) refluxers, depending on the posture in which abnormal reflux occurred. Esophageal pH monitoring during the 3-hr postprandial upright period showed abnormal reflux in only 35 patients (sensitivity 53.8%;P<0.00005, compared with the 24-hr pH monitoring period). Abnormal GER was identified in 13 of 18 upright, 19 of 23 combined, and only one of 15 supine refluxers, as well as in two of nine patients with normal 24-hr pH-metry. However, inclusion of the 3-hr supine monitoring period in the 3-hr postprandial upright period improved detection of abnormal GER to 78.5% (51 patients;P=NS compared with 24-hr pH monitoring period). This was related mainly to improved detection of abnormal GER in supine refluxers (11 of 15; 73.3%). Esophageal acid exposure time correlated significantly with severity of esophagitis only during the total and supine periods of both the 24- and 6-hr periods and not during the upright period. Esophageal acid clearance correlated significantly with increasing grades of esophagitis for the supine and total periods only. We conclude that 3-hr postprandial pH monitoring, as has been conventionally practiced, is not appropriate in the detection of abnormal GER; inclusion of a supine period in the short-duration pH monitoring schedule increases the detection of pathological reflux. We therefore recommend that a supine period should be included in short-duration pH monitoring schedules. We also found that supine reflux was the most important factor in the development of esophagitis.     

Validation of a new method of measuring esophageal acid exposure: comparison with 24-hour pH monitoring

Recently, we developed a disposable acid exposure sensor whose in vitro response to acid below pH 4 is linearly determined by the duration of exposure and the degree of acidity. The aim of the present study was to compare the SR to simultaneous esophageal pH and duodenogastroesophageal reflux (DGER) monitoring (Bilitec) in patients investigated for presumed gastroesophageal reflux disease (GERD). Twenty-six patients (16 men, mean age 46 ± 2 years) with symptoms suggestive of GERD underwent 24-hr ambulatory pH monitoring and SR monitoring at 5 cm proximal to the LES. DGER monitoring was performed in 21 patients. Exposure of the esophagus to acid and to DGER were analyzed. These data were compared to SR. A significant correlation was found between the exposure of the distal esophagus to acid and SR (R = 0.85; P < 0.0001). Similarly, the area below a cutoff pH 4 was significantly correlated to SR (r = 0.81; P < 0.0001). SR was not correlated to DGER (r = 0.16; NS). At a cutoff of 50, the sensitivity and specificity of SR to predict esophageal acid exposure >5% of time were 91% and 93%, respectively conclusion, the response of the acid exposure sensor is strongly correlated with the results of simultaneous esophageal pH monitoring. The sensor seems able to reliably predict pathological esophageal acid exposure. These findings warrant larger studies of the clinical potential of the acid exposure sensor in the diagnosis and quantification of GERD.     

反流性食管炎和非糜烂性反流病患者酸暴露与食管压力监测结果分析

目的通过对胃食管反流病（GERD）患者的酸暴露情况、食管下括约肌（LES）压力、食管体部压力、幽门螺杆菌（Hp）感染结果的比较，探讨反流性食管炎（RE）、非糜烂性反流病（NERD）的不同状况，为临床治疗提供科学依据。方法2001年10月至2005年7月，具有反流症状（烧心、反酸）的患者80例，胃镜检出RE31例，NERD45例，Barrett食管（BE）4例。行食管24hpH动态监测，并以De—Meester积分均值将GERD分为轻、中、重度，检测LES、食管体部即LES上方5cm、7cm、13cm（简记为L5、L7、L12）和食管上括约肌（UES）下方1cm、6cm、8cm（简记为U1、U6、U8）压力指标，并进行Hp感染的检查。结果RE、NERD两组患者食管24hpH酸暴露各指标的差异，无统计学意义（P〉0．05），De-Meester积分均值亦无统计学意义（P〉0．05）；轻、中、重度GERD患者食管24hpH监测指标具有统计学意义（P〈0．01）。RE、NERD两组患者LES压力、食管体部的L5、L7、L12、U6和u8压力监测指标无统计学意义（P〉0．05），只有RE组U1压力低于NERD组，差异有统计学意义（P〈0．05）；轻、中、重度GERD患者LES压力和食管体部的压力监测指标差异无统计学意义（P〉0．05）。RE和NERD组患者Hp感染率分别为16．1％和22．2％，其差异无统计学意义（P〉0．05），OR为1．309，95％C10．364～4．705。结论RE和NERD患者酸暴露、LES压力和食管体部压力等相应指标无明显差异；NERD在发病机制中，酸反流的强弱没有起到决定性作用。     

Correlation of 24-hr esophageal pH patterns with clinical features and endoscopy in gastroesophageal reflux disease

We performed 24-hr ambulatory esophageal pH monitoring in north Indian patients with gastroesophageal reflux disease (GERD) and correlated it with symptom severity and endoscopic abnormalities. Thirty-six consecutive patients with symptomatic GERD and 16 healthy volunteers underwent objective grading of clinical symptoms and endoscopic findings. Total, supine, and upright reflux periods as well as frequency and duration of reflux episodes were determined from the 24-hr pH-metry record using standard software. This was abnormal in 32 patients, who could be categorized into upright refluxers (31.2%), supine refluxers (34.4%), and combined refluxers (34.4%). Supine reflux and upright reflux were distinct entities that did not correlate with each other (r=0.22,P=NS). In upright refluxers, symptoms (P<0.02) and=" endoscopic=" abnormalities=">P<0.005) were=" milder=" than=" in=" combined=" refluxers.=" total=" duration=" of=" acid=" exposure=" correlated=" significantly=" with=" severity=" of=" symptoms=">P<0.001) and=" endoscopic=" esophagitis=">P<0.005). patients=" with=" gerd=" had=" three=" distinct=" patterns=" of=" abnormal=" gastroesophageal=" reflux,=" with=" upright=" refluxers=" having=" milder=" disease=" and=" supine=" and=" combined=" refluxers=" having=" more=" severe=" disease.=" this=" may=" reflect=" differences=" in=" underlying=" mechanisms=" of=">     

Upright versus supine reflux in gastroesophageal reflux disease

BACKGROUND: Postural measures are early recommendations in the management of heartburn, and are aimed at preventing acid reflux through an incompetent lower esophageal sphincter (LES). However, LES incompetence is found in only a minority of patients, and transient LES relaxations, primarily in the upright position, are currently recognized as the main pathophysiological abnormality in gastroesophageal reflux disease (GERD). We investigated the importance of supine acid reflux in patients with GERD. METHODS: Upon review of their clinical, manometric, pH monitoring and endoscopic characteristics, 85 patients with reflux symptoms were classified into three groups: Group A (n=22), consisting of symptomatic patients without esophagitis or pathological reflux; group B (n=38), symptomatic patients with reflux but no endoscopic esophagitis; and group C (n=25), symptomatic patients with both ulcerative or complicated esophagitis and pathological reflux. RESULTS: All groups were similar in age distribution. Groups B and C had a higher prevalence of hiatal hernia and reflux symptoms. Manometry revealed similar LES pressures in groups A and B, but lower LES pressure in group C (P < 0.005). In groups A and B, supine reflux, in terms of percentage of time with pH < 4, was less pronounced than upright reflux (P < 0.0001). In contrast, group C supine reflux was as pronounced as the upright reflux. CONCLUSIONS: The majority of patients reflux in the upright position. Only patients with complicated esophagitis have significant bipositional acid reflux. These findings suggest that unless the patient has severe reflux disease, postural measures may not be indicated.     

Symptom Predictability of Reflux-Induced Respiratory Disease

Gastroesophageal reflux disease (GERD) often is associated with pulmonary problems such as asthma as well as recurrent and nocturnal cough. Dual-probe 24-hr pH monitoring may assist in establishing a correlation between these symptoms and GERD-related symptoms. To determine if any specific symptom was predictive of aspiration, this study was undertaken. Ambulatory dual-probe esophageal pH monitoring was performed on 133 patients who had upper airway and additional symptoms for GERD. All patients had esophageal manometric studies of the lower esophageal sphincter (LES), the upper esophageal sphincter (UES), and the esophageal body before dual-probe pH monitoring was performed. Using two assembled glass probes, the distal and the proximal sensors were placed 5 cm above the proximal border of the LES and 1 cm below the lower border of the UES, respectively. Patients were classified into three groups: proximal and distal probe positive (group I), proximal probe negative and distal probe positive (group II) and proximal and distal probe negative (Group III) Upper airway and additional symptoms plus manometry results of the LES, body and UES study were compared between groups. In addition, positive distal probe patients (groups I and II) were compared for distal fraction of time at pH < 4 and number of reflux episodes at each probe position. A positive distal probe result was defined as an abnormal DeMeester score (>14.8). A proximal probe test result was considered positive if percent time pH < 4.0 was >1.1 for total, 1.7 for upright, and 0.6 for supine positions. The ages of the subjects ranged from 18 to 83 years (mean age: 50.5 ± 1.5 years). Groups I, II, and III included 16 patients, 38 patients, and 79 patients, respectively. Group I had a significantly higher incidence of nocturnal cough than the other two groups. (P < 0.05). The manometric data revealed between groups that LES pressure (LESP) for groups I and II was significantly lower than LESP for group III (P = 0.003). Cricoid pressure, pharyngeal pressure, length, and relaxation of UES were not different between groups. Fraction of reflux time for group I was significantly higher than for group II in the supine position and at mealtime (P < 0.05). The number of reflux episodes for group I was significantly higher at meal time (P < 0.01). In conclusion, nocturnal cough is strongly predictive of proximal esophageal reflux. Proximal reflux episodes are significantly more frequent in the supine position and correlate well with the high predictive value of nocturnal cough.     

Mechanisms of Excessive Esophageal Acid Exposure in Patients with Reflux Esophagitis

The pathophysiology of excessive esophageal acid exposure, including the way refluxed acid extends towards the proximal esophagus, in patients with reflux esophagitis (RE), is not yet clear. For 3 h after a meal, concurrent esophageal manometry and pH monitoring was carried out on 14 patients with severe RE, 15 patients with mild RE, and 15 healthy subjects. At 2 cm above the proximal margin of the lower esophageal sphincter (LES) there was no difference between the three groups in the total number of acid-reflux episodes, the rate of transient LES relaxations (TLESRs), or the rate of acid reflux during TLESRs. The rate of acid reflux at 7 cm above the proximal margin of the LES, during TLESRs, in patients with severe RE (50.9%, median) was, however, significantly higher than in patients with mild RE (35.7%) and healthy subjects (15.4%). In addition, the rate of acid reflux during TLESRs in patients with mild RE was significantly higher than in healthy subjects. Both the amplitude and the success rate of primary peristalsis in patients with severe RE were significantly lower than those of healthy subjects and patients with mild RE but there was no difference between healthy subjects and patients with mild RE. The cause of excessive acid exposure in patients with RE is the difference in the way refluxed acid extends towards the proximal esophagus and acid bolus clearance, not the number of acid-reflux episodes.     

Gastroesophageal pH step-up inaccurately locates proximal border of lower esophageal sphincter

Limiting the widespread use of 24-hr pH monitoring is the necessity of manometrically placing the pH probe 5 cm above the proximal lower esophageal sphincter (LES) border. Therefore, we prospectively compared LES localization by gastroesophageal pH step-up with manometry in 71 patients and 14 asymptomatic volunteers. The gastroesophageal pH step-up significantly correlated with the proximal LES border in patients (r=0.53, P<0.0001) and volunteers (r=0.91, P<0.0001). Based on previously published criteria, the pH step-up value was considered acceptably accurate if it was within ±3 cm (6 cm total span) of the manometrically determined proximal LES border. In 58% of patients and 29% of volunteers the pH step-up occurred outside this accuracy range. Esophagitis (P=0.015) and abnormal reflux parameters (P=0.002) were variables contributing to this error. Subsequent analysis found that the pH step-up overestimated the proximal LES border and occurred at the midportion of the sphincter. The pH step-up still inaccurately located the mid LES in 34% of patients. Therefore, manometry should remain the standard for accurate LES localization prior to placing the pH probe.     

Determination of pH turning point with pH mapping of the gastroesophageal junction: an alternative technique to orientate esophageal pH monitoring

Manometric location of the lower esophageal sphincter (LES) has been mandatory before esophageal pH monitoring, despite costs and discomfort related with esophageal manometry. The aims of the study were: (i) to map the pH of the gastroesophageal junction (GEJ) to determine a pH turning point (PTP) and its relation with LES; and (ii) to test the feasibility of this technique to orientate esophageal pH monitoring. We studied 310 adult patients who underwent esophageal manometry and pH monitoring off acid‐suppressive therapy. GEJ pH mapping was carried out by step‐pulling the pH sensor from 5 cm below to 5 cm above LES, and a PTP was determined when pH changed from below to above 4, in centimeters from the nostril. Thirty‐six patients referred only for pH monitoring were studied with pH sensor placed at 5 cm above the PTP. Out of 310 patients, a PTP was found in 293 (94.5%): inside LES in 86.3%, into the stomach in 8.2% and in the esophageal body in 5.5% of patients. The median distance between PTP and place where pH sensor monitored reflux was 8 cm. Among 36 patients who performed pH monitoring without LES manometry, there was no gastric monitoring during reflux testing. In adult patients investigated off acid suppressive therapy, GEJ pH mapping with reflux monitoring 5 cm above the PTP can be an alternative technique to perform esophageal pH monitoring when LES manometry is not available. Additional studies are needed before the widespread use of GEJ pH mapping in the clinical practice.     

Use of multiple channel pH monitoring for evaluation of ultra‐distal reflux in patients after fundoplication for treatment of Barrett's esophagus

Dysplasia and esophageal adenocarcinoma may arise in patients with Barrett's esophagus after fundoplication esophageal pH monitoring showing no acid in esophagus. This suggests the need to develop methodology to evaluate the occurrence of ultra‐distal reflux (1 cm above the LES). The objective of the study was to compare acid exposition in three different levels: 5 cm above the upper border of the LES, 1 cm above the LES and in the intrasphincteric region. Eleven patients with Barrett's esophagus after Nissen fundoplication with no clinical, endoscopic and radiologic evidence of reflux were selected. Four‐channel pH monitoring took place: channel A, 5 cm above the upper border of the LES; channel B, 1 cm above the LES; channel C, intrasphincteric; channel D, intragastric. The results of channels A, B and C were compared. There was significant increase in number of reflux episodes and a higher fraction of time with pH <4.0 in channel B compared to channel A. There was significant decrease in fraction of time with pH <4.0 in channel B compared to channel C. Two cases of esophageal adenocarcinoma were diagnosed in the studied patients. The region 1 cm above the upper border of the LES is more exposed to acid than the region 5 cm above the upper border of the LES, although this exposure occurred in reduced levels. The region 1 cm above the upper border of the LES is less exposed to acid than the intrasphincteric region.     

Exclusion of meal periods from ambulatory 24-hour pH monitoring May improve diagnosis of esophageal acid reflux

Distal esophageal pH less than 4 is frequently seen during meal ingestion in 24-hr ambulatory pH monitoring for the diagnosis of gastroesophageal reflux disease (GERD). The characteristics of this meal-related apparent reflux without diet restriction was evaluated. Data from normal volunteers (N=21) and consecutive patients (N=66) referred with heartburn and/or chest pain were studied with ambulatory pH monitoring. The median percent times pH<4 in the distal esophagus were significantly greater in symptomatic patients than controls for total 24-hr, upright, and supine periods, and postprandial periods of 30, 60, 90, 120, and 150 min (P values of 0.007–0.03). However, the median percent time pH<4 during the meal periods was the same for patients (4.4%) and for controls (6.6%) withP=0.23. Excluding the meal periods from analysis resulted in greater separation between controls and patients with abnormal acid exposure when compared to the conventional method. Patients should maintain their usual routine without diet restriction during 24-hr ambulatory pH studies in the clinical setting. Furthermore, exclusion of meal periods can eliminate meal-time pH variabilities without affecting postprandial acid exposure and improve the diagnosis of GERD.     

The role of excessive esophageal acid exposure in patients with gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD), especially reflux esophagitis (RE), is characterized by excessive esophageal acid exposure. Transient lower esophageal sphincter (LES) relaxation is the major mechanism of acid reflux episodes in both healthy subjects (HS) and patients with GERD. In the sitting position, where acid reflux episodes often occur, there is no difference in the frequency of transient LES relaxations between these two groups; however, in patients with GERD, at 5 cm above the LES, the proportion of acid reflux episodes during transient LES relaxations is significantly greater than in the HS group. This difference is considered to be one of the causes of excessive esophageal acid exposure in patients with GERD, but its cause is still unclear. A recent study, which investigated the proportion of acid reflux episodes during transient LES relaxations at 2 and 7 cm above the LES, showed that there was no difference at 2 cm above the LES between HS and patients with RE, but at 7 cm they were significantly greater in patients with RE than in HS. Evaluation of acid reflux at 2 cm above the LES is difficult to measure, but the proximal extent of refluxate could be one of the important factors of excessive acid esophageal exposure in patients with RE. Ineffective esophageal motility, found in patients with moderate to severe RE, impairs esophageal bolus clearance of acid, therefore both the proximal extent of refluxate and the delay of esophageal bolus clearance of acid could be major causes of excessive esophageal acid exposure. Hiatus hernia also causes acid reflux, due to its association with hypotensive LES, and also impairs esophageal bolus clearance of acid.     

Acid and Non-Acid Reflux Patterns in Patients with Erosive Esophagitis and Non-Erosive Reflux Disease (NERD): A Study Using Intraluminal Impedance Monitoring

Background Non-erosive reflux disease (NERD) and erosive esophagitis (EE) are the most common phenotypic presentations of gastroesophageal reflux disease (GERD). Aim To assess acid and non-acid reflux patterns in patients with EE and NERD using combined esophageal pH-impedance monitoring. Methods A total of 26 GERD patients off acid-suppressive medication and ten healthy volunteers (HV) underwent upper endoscopy and 24-h pH-impedance monitoring. Analysis of the pH-impedance signals included total reflux time, number of reflux episodes according to gas–liquid composition, and pH (acid, non-acid). Results EE was identified in 13 patients and NERD in 13 patients. Pathologic acid reflux was found in 92.3 and 69.2% of patients with EE and NERD, respectively (P = 0.15). When compared to HV, EE patients and NERD patients showed a higher incidence of acid (P = 0.002 and P < 0.001, EE vs. HV and NERD vs. HV, respectively) and non-acid reflux episodes (P = 0.03 and P = 0.001, EE vs. HV and NERD vs. HV, respectively). Mean reflux times, as assessed by both pH-metry and impedance monitoring, and incidence of acid and non-acid reflux episodes were similar in EE and NERD patients. In the supine position, however, EE patients showed a higher incidence of acid (P = 0.048) and liquid reflux episodes (P = 0.07). Conclusion Whereas EE patients have more acid reflux episodes in the supine position than NERD patients, patients with EE and NERD have similar non-acid reflux patterns. This observation lends support to the notion that non-acid reflux is less damaging to the esophageal mucosa than acid reflux.     

胃食管反流病食管酸暴露和食管动力学变化特征

目的探讨无效食管动力(IEM)在胃食管反流病(GERD)中的作用,以及体质量对食管酸暴露及食管动力的影响。方法77例GERD典型症状患者全部行食管高分辨率压力测定(HRM)和24 h食管动态pH监测,分析IEM及正常食管动力患者酸暴露情况。结果 77例典型GERD症状患者中病理性酸暴露者38例(49%),在病理性酸暴露组中IEM 9例(24%),正常酸暴露组中IEM 5例(13%)。IEM组LES压力低于食管动力正常组(15.15±3.60 vs 22.15±6.73,P0.01);IEM组总pH4时间(百分比)较正常食管动力组高[(14.78±3.8)%vs(4.30±2.68)%,P0.01];IEM组患者BMI值较高。结论 IEM在GERD中较常见,其食管动力障碍中绝大多数为IEM,IEM与食管远端酸暴露密切相关。     

Comparison of esophageal acid exposure distribution along the esophagus among the different gastroesophageal reflux disease (GERD) groups

BACKGROUND: Patients with nonerosive reflux disease (NERD) have the lowest esophageal acid exposure profile compared with the other gastroesophageal reflux disease (GERD) groups. AIM: To compare lower esophageal acid exposure recordings 1 cm above the lower esophageal sphincter (LES) with those 6 cm above the LES as well as to determine the characteristics of esophageal acid exposure along the esophagus among the different GERD groups. METHODS: Patients with classic heartburn symptoms were enrolled into the study. Patients were evaluated by a demographics questionnaire and the validated GERD Symptom Checklist. Upper endoscopy was performed to evaluate the presence of esophageal erosions and Barrett's esophagus (BE). Ambulatory pH testing was performed using a commercially available 4-sensor pH probe with sensors located 5 cm apart. The distal sensor was placed 1 cm above the LES. RESULTS: Sixty-four patients completed the study. Of those, 21 patients had NERD, 20 had erosive esophagitis (EE), and 23 had BE. All patient groups demonstrated greater esophageal acid exposure 1 cm above the LES than 6 cm above the LES. In NERD and EE, this phenomenon was primarily a result of a higher mean percentage of upright time with pH <4. Unlike patients with EE and BE, those with NERD had very little variation in esophageal acid exposure throughout the esophagus (total and supine). CONCLUSIONS: ALL GERD groups demonstrated significant greater esophageal acid exposure at the very distal portion of the esophagus, primarily as a result of short upright reflux events. Unlike erosive esophagitis and BE, NERD patients demonstrate a more homogenous acid distribution along the esophagus.     

Comparison of esophageal acid exposure at 1 cm and 6 cm above the squamocolumnar junction using the Bravo™ pH monitoring system

The aim of this study was to assess the quantitative differences of acid exposure at 1 cm and 6 cm above the squamocolumnar junction (SCJ) using two radiotelemetry pH capsules affixed to the esophageal mucosa. Ten normal subjects and 10 endoscopy-negative gastroesophageal reflux disease (GERD) patients without hiatus hernia (ages 20-54, 12 male) were studied for a 24-h period using the Bravo pH monitoring system. pH capsules were placed 1 cm and 6 cm above the SCJ. Interpretable data for at least 14 h was obtained in 18 of the 20 subjects (9 normal, 9 GERD). Two failures occurred secondary to early capsule dislodgement. Median esophageal acid exposure was significantly increased at 1 cm above the SCJ compared to 6 cm above the SCJ during the total, upright and postprandial time periods in both normal and GERD subjects. During a 2 h postprandial period the esophageal acid exposure was 8-fold greater in GERD subjects and 5-fold greater in normal subjects 1 cm above the SCJ compared to 6 cm above the SCJ. Confident measurement of esophageal acid exposure at a fixed position 1 cm above the SCJ is feasible with the Bravo system. Acid exposure was significantly higher 1 cm above the SCJ compared to 6 cm above the SCJ in both GERD patients and controls. These findings suggest that measurement of acid exposure 1 cm above the SCJ may improve accuracy of pH monitoring by detecting acid reflux events confined to the distal esophagus.     

Influence of the esophageal hiatus size on the lower esophageal sphincter, on reflux activity and on symptomatology

Hiatal hernia is an underlying factor contributing to gastroesophageal reflux disease (GERD). However, it remains elusive whether the size of the esophageal hiatus has a de facto influence on the lower esophageal sphincter (LES), on the intensity of patient reflux, on GERD symptoms and on the quality of life (QoL). One hundred patients with documented chronic GERD underwent laparoscopic fundoplication. QoL was evaluated before surgery using the Gastrointestinal Quality of Life Index (GIQLI). Additionally, GERD symptoms and nonspecific gastrointestinal symptoms were documented using a standardized questionnaire (score 0-224). The size of the esophageal hiatus was measured during surgery by calculating the hiatal surface area (HSA). Correlation analysis between the preoperative QoL, GERD symptoms, esophageal manometry, multichannel intraluminal impedance monitoring data and HSA size was performed, in order to investigate whether the HSA has an influence on the patients'symptoms, GIQLI, manometry and multichannel intraluminal impedance monitoring data. Statistical significance was set at a P-value of 0.05. The HSA sizes ranged from 1.51cm(2) to 16.09cm(2) (mean 4.14cm(2) ). The preoperative GIQLI ranged from 15 points to 133 points (mean 94.37 points). Symptom scores ranged from 2 points to 192 points (mean 49.84 points). No significant influence of the HSA on GIQLI or preoperative symptoms was recorded. HSA size had a significant negative effect on LES pressure. Additionally, there was a significant positive correlation between HSA size and number of refluxes in supine position. For the rest of the evaluated data, including DeMeester score, total number of refluxes, refluxes in upright position, acid reflux events, proximal reflux events, LES length and body motility, no significant correlation was found. Although patients subjectively are not significantly affected by the size of the hiatus, it has significant effects on the LES pressure and on gastroesopageal reflux in supine position.     

Direct Comparison of Impedance,Manometry, and pH Probe in Detecting Reflux Before and After a Meal

Combining GERD tests allows strengths and weaknesses of each method to be identified in detecting and characterizing reflux (RE). Aim of this study was to compare two methods that measure bolus volume of a refluxant (impedance monitoring (Imp) and manometry (common cavity)) to pH monitoring which measures changes in acid concentration of a refluxant. Nineteen symptomatic GERD patients and 10 normal volunteers were studied before and after a meal. All had 2-hr simultaneous manometry, pH, and Imp (six sites: 3, 5, 7, 9, 15, 17 cm above LES). Reflux by pH was a fall in pH from above to below 4. There were 973 RE’s in all subjects, but only 19% were detected simultaneously by all three methods. Imp detected more RE’s (96%) than manometry (76%) or pH probe (28%). Imp was the only method to detect 15% (144/973) of RE’s, while detection only by pH probe (2%) or manometry (2%) was rare. Most RE’s detected by Imp were detected simultaneously by manometry (75%,720/937). Those not detected by manometry were usually in blind spots either in the vulnerable period 2–3 sec after a swallow, during a posture change, or during a Valsalva. Most RE’s detected by Imp were not detected by the pH probe. Though most liquid RE’s fasting were detected by pH, most liquid postprandial RE’s were not, due primarily to weakly acidic rather than superimposed acid RE’s. Bolus clearing time by Imp and manometry was nearly identical, while acid clearing was threefold longer than bolus clearing by Imp or manometry. In conclusion, impedance monitoring is better than manometry and pH monitoring in RE detection before and after a meal, and manometry in determining RE composition as liquid or gas. The pH probe measures RE acidity and acid clearing. Simultaneous impedance and pH combines the two methods strengths, and is a powerful tool for reflux detection and characterization.     

Females without reflux symptoms or gastroesophageal reflux disease have less distal esophageal acid exposure than males without reflux symptoms or gastroesophageal reflux disease

Ambulatory 24‐hour esophageal pH monitoring is the gold standard examination to assess esophageal acid exposure. Gender‐related variation is a well‐recognized physiologic phenomenon in health and disease. To date, limited gender‐specific 24‐hour esophageal pH monitoring data are available. The aim of this study was to obtain values of esophageal pH monitoring in males and females without reflux symptoms or gastroesophageal reflux disease (GERD) to determine if gender variation exists in esophageal acid exposure among individuals without these factors. Twenty‐four‐hour dual esophageal pH monitoring was performed in male and female volunteers without reflux symptoms or GERD. Values for total number of reflux episodes, episodes longer than 5 minutes, total reflux time in minutes, % time with pH below 4, and longest reflux episode in the proximal/distal esophagus were obtained and recorded for both groups. The distal channel was placed 5 cm and proximal channel 15 cm above the manometrically determined lower esophageal sphincter. Means were compared using an independent sample t‐test. Sixty‐seven males and 69 females were enrolled. All subjects completed esophageal 24‐hour pH monitoring without difficulty. There was no age or body mass difference between groups. Females had significantly fewer reflux episodes at both esophageal measuring sites and, significantly less total reflux time and % time with pH below 4 in the distal esophagus than males. All other parameters were similar. Significant gender‐related differences exist in esophageal acid exposure, especially in the distal esophagus in individuals without reflux symptoms or GERD. These differences underscore the need for gender‐specific reference values for 24‐hour pH monitoring, allowing for an accurate evaluation of esophageal acid exposure in symptomatic patients.