I. Bravi

Multiple rapid swallowing: a complementary test during standard oesophageal manometry

Abstract  Multiple rapid swallowing (MRS) stimulates neural inhibition resulting in abolition of contractions in the oesophageal body (OB) and complete lower oesophageal sphincter (LOS) relaxation which is followed by peristalsis and LOS contraction. The aim of this study was to evaluate the yield of MRS to detect abnormalities in inhibitory or excitatory oesophageal mechanisms in patients with oesophageal symptoms and either normal standard manometry or ineffective oesophageal motility (IOM). MRS (five water swallows, 2 mL, separated by 2–3 s) was evaluated in 23 healthy subjects, 109 symptomatic patients with normal standard sleeve manometry and in 48 patients with IOM. Healthy subjects had complete inhibition of OB motility during MRS and a strong motor response after MRS, i.e. amplitude of OB contractions in the oesophageal body and LOS tone being higher than after single swallows. Almost 70% of patients with oesophageal symptoms and normal manometry had abnormal MRS, mainly consistent on inability to increase amplitude of OB contractions after MRS. Nearly, half of the patients with IOM were able to normalize OB contractions after MRS. MRS is a simple complementary test that can be added to standard oesophageal manometry. Two‐thirds of patients with normal manometry show abnormal MRS that could potentially underlie their symptoms. A normal response to MRS in patients with severe IOM might be used to predict response to prokinetic treatment.

A pneumatic dilation strategy in achalasia: prospective outcome and effects on oesophageal motor function in the long term

Aliment Pharmacol Ther 31, 658–665

The role of delayed gastric emptying and impaired oesophageal body motility

Delayed gastric emptying in a variable proportion of patients with gastro-oesophageal reflux disease has been observed in most series, however a relationship between delayed gastric emptying and increased gastro-oesophageal reflux has not been convincingly demonstrated. Enhanced postprandial accommodation and delayed emptying of the proximal stomach have been described, but some controversy exists. Impaired primary peristalsis is often present especially in patients with oesophagitis and its prevalence increases with increasing severity of inflammatory mucosal lesions. Patients with gastro-oesophageal reflux disease often have defective triggering of secondary peristalsis independently of presence of oesophagitis. It is presently unclear if impaired oesophageal motility is a primary defect or an irreversible consequence of inflammation. Attempts at pharmacological improvement of impaired oesophageal motility have been so far disappointing. Patients with partially preserved neuromuscular structures need to be identified in order to select them for new prokinetic therapy.

Usefulness of low- and high-volume multiple rapid swallowing during high-resolution manometry.

BACKGROUND It has been suggested that multiple rapid swallowing should be added to oesophageal manometry. AIM To prospectively evaluate whether 10 and 200 mL multiple rapid swallowing provide different information concerning motor function. METHODS 30 consecutive patients with oesophageal symptoms, 13 achalasia patients after successful pneumatic dilation and 19 healthy subjects performed eight 5 mL single swallows, two 10 mL and one 200 mL multiple rapid swallowing. RESULTS Almost all of the healthy subjects and two-thirds of the patients with oesophageal symptoms showed motor inhibition during both 10 and 200 mL multiple rapid swallowing. The oesophago-gastric pressure gradient was significantly higher during 200 mL multiple rapid swallowing within each group (p < 0.01), and significantly higher in the achalasia patients than in the other two groups (p < 0.0001). Presence of a contraction and increased contraction strength in comparison with single swallows were both more frequent after 10 mL than after 200 mL multiple rapid swallowing in the healthy subjects and the patients (p<0.05). CONCLUSION Motor inhibition could be similarly evaluated by means of 10 and 200 mL multiple rapid swallowing; 10 mL evaluated the after-contraction, whereas 200 mL multiple rapid swallowing was more valuable in identifying increased resistance to outflow.

Increased Prandial Air Swallowing and Postprandial Gas-Liquid Reflux Among Patients Refractory to Proton Pump Inhibitor Therapy

BACKGROUND & AIMS Many patients with gastroesophageal reflux disease (GERD) have persistent reflux despite treatment with proton pump inhibitors (PPIs). Mixed gas-liquid reflux events are more likely to be perceived as symptomatic. We used esophageal impedance monitoring to investigate whether esophageal gas is processed differently among patients with GERD who do and do not respond to PPI therapy. METHODS We performed a prospective study of 44 patients with typical reflux symptoms with high levels of esophageal acid exposure during a 24-hour period; 18 patients were fully responsive, and 26 did not respond to PPI therapy. Twenty-four-hour pH impedance recordings were analyzed for fasting and prandial air swallows and reflux characteristics, including the presence of gas in the refluxate. RESULTS PPI-refractory patients had a higher number (83.1 ± 12.7 vs 47.8 ± 7.3, P < .05) and rate (10.5 ± 1.4 vs 5.9 ± 0.8/10 minutes, P < .05) of prandial air swallows than patients who responded to PPI therapy; they also had a higher number (25.5 ± 4.0 vs 16.8 ± 3.3, P < .05) and proportion (70% ± 0.03% vs 54% ± 0.06%, P < .05) of postprandial, mixed gas-liquid reflux. Symptoms of PPI-refractory patients were more often preceded by mixed gas-liquid reflux events than those of PPI responders. Fasting air swallowing and other reflux characteristics did not differ between patients who did and did not respond to PPIs. CONCLUSIONS Some patients with GERD who do not respond to PPI therapy swallow more air at mealtime than those who respond to PPIs and also have more reflux episodes that contain gas. These factors, combined with mucosal sensitization by previous exposure to acid, could affect perception of symptoms. These patients, who can be identified on standard 24-hour pH impedance monitoring, might be given behavioral therapy to reduce mealtime air swallowing.

Subcardial 24-h Wireless pH Monitoring in Gastroesophageal Reflux Disease Patients With and Without Hiatal Hernia Compared With Healthy Subjects

OBJECTIVES:After meals, highly acidic gastric juice is present in the subcardial region, the so-called acid pocket. Patients with gastroesophageal reflux disease (GERD) have a higher frequency of acidic reflux. Our aim was to investigate the possible differences in subcardial pH in GERD over 24 h and the role of hiatal hernia (HH), using a wireless capsule.METHODS:A total of 14 healthy volunteers (4 men, 24–60 years), 10 GERD patients without HH (4 men, 25–68 years), and 11 GERD patients with HH ≥3 cm (2 men, 46–74 years) underwent 24-h wireless pH monitoring 2 cm below the squamocolumnar junction. All patients had increased 24-h acid reflux. A standardized lunch was given to all study subjects.RESULTS:No capsule detached during the 24-h recording. Median 24-h pH was similar in healthy subjects, and in patients without and with HH, median: 1.4 (interquartile range: 1.2 –1.9), 1.5 (1.3 –1.7), and 1.4 (1.3 –1.7), respectively. Similar results were seen in the supine period. Median pH after the standardized meal was often highly acidic, 2.7 (1.5 – 3.2), 1.9 (1.6 – 2.3), and 2.5 (1.6 – 3.2), respectively. The first minute with a median pH <2 occurred 14 min (4 – 49), 14 min (6 – 25), and 20 min (4 – 43), respectively, P=NS, after the end of the meal. Similar data were observed on pooling all meals together.CONCLUSIONS:Subcardial pH is confirmed to be highly acidic early after meals, but it is similar over 24 h in healthy subjects and GERD patients independent of the presence of HH.

Functional testing: Pharyngeal pH monitoring and high-resolution manometry

The following paper on functional testing of the pharynx includes commentaries on the use of 24‐h pH–impedance testing to identify patients with nonacid reflux and the caveats associated with automatic and visual analysis; the potential diagnostic yield of ambulatory high‐resolution manomentry (HRM), particularly in identifying non‐cardiac chest pain and transient lower esophageal sphincter relaxations; the differential manometric identification of conditions facilitated by using solid swallows, and the advantages of the newly developed ResTech oropharyngeal pH probe in the detection of proximal reflux events.

Postprandial cardiac vagal tone and transient lower esophageal sphincter relaxation (TLESR)

Transient lower esophageal sphincter relaxation (TLESR) is a vagally mediated reflex that occurs most frequently after a meal. Cardiac vagal tone (CVT) decreases after a meal, and correlates with changes in gastric electrical activity. Furthermore, decreased CVT has been reported in patients with gastro‐esophageal reflux disease. We therefore aimed to characterize the association between postprandial changes in CVT and the occurrence of TLESR and reflux.

Impedance pH Monitoring: Intra-observer and Inter-observer Agreement and Usefulness of a Rapid Analysis of Symptom Reflux Association

Background/Aims Symptom reflux association analysis is especially helpful for evaluation and management of proton pump inhibitor (PPI) refractory patients. An accurate calculation requires manual editing of 24-hour multichannel intraluminal impedance-pH (MII-pH) tracings after automatic analysis. Intra- and inter-observer agreement as well as reliability of rapid editing confined to the time around symptomatic episodes are unknown. Aim of this study was to explore these topics in a prospective multicenter study. Methods Forty consecutive patients who were off PPI therapy underwent MII-pH recordings. After automatic analysis, their tracings were anonymized and randomized. Three experienced observers, each one trained in a different European center, independently performed manual editing of 24-hour tracings on 2 separate occasions. Values of symptom index and symptom association probability for acid and non acid reflux were transformed into binary response (i.e., positive or negative). Results Intra-observer agreement on symptom reflux association was 92.5% to 100.0% for acid and 85.0% to 97.5% for non-acid reflux. Inter-observer agreement was 100.0% for acid and 82.5% to 95.0% for non-acid reflux. Values for symptom index and symptom association probability were similar. Concordance between 24-hour and rapid (2 minutes-window before each symptomatic episode) editings for symptom reflux association occured in 39 to 40 patients (acid) and in 37 to 40 (non-acid), depending on the observer. Conclusions Intra- and inter-observer agreement in classifying patients with or without symptom reflux association at manual editing of 24-hour tracings was high, especially for acid reflux. Classifying patients according to a rapid editing showed excellent concordance with the 24-hour one and can be adopted in clinical practice.

Computer simulator among experts involved in screening colonoscopy

Background In the era of screening colonoscopy, assessment of operator competence is warranted. Aim To evaluate feasibility of a computer simulator (CS) use for assessment of competence in colonoscopy by investigating performance of expert endoscopists at CS. Subjects Twenty expert endoscopists involved in screening colonoscopy. Methods Experts returned a questionnaire regarding personal practice (duration of activity, number of colonoscopies in the last year and assistance by a nurse) and performances (percentage of caecal intubation and polyp detection rate). One easy and one difficult colonoscopy were proposed at CS in randomized order. Results Participation rate was 75%. Caecal intubation rate in clinical practice was more than 90% for all experts. At CS, time to caecal intubation and number of attempts for ileal intubation were significantly lower during easy versus difficult colonoscopy (P<0.01 for both items); interestingly, percentage of mucosa explored was higher (P<0.05) during the difficult simulation. Withdrawal time ≥6 min was achieved by 40 and 33% of experts during the easy and difficult simulation, respectively. Independent of simulation difficulty, time with loop was lower (P<0.05) for experts using hands-free insertion (n = 8) compared with those using nurse assistance in their clinical practice (n = 7). No correlation was found between scores at CS and performance in clinical practice. Conclusion Scores at CS are sensitive to the rate of technical difficulty and nurse assistance during daily practice. Withdrawal time is often shorter than required for high accuracy in polyp detection. CS could be a well-accepted tool for assessment of competence.