Water-perfused High-resolution Manometry Research Articles

London Protocol under water-perfused HRM in a healthy population, towards novel 3D manometric parameters in an evaluation of anorectal functional disorders

Background/AimLondon Protocol (LP) and Classification allied to high-resolution manometry (HRM) technological evolution has updated and enhanced the diagnostic armamentarium in anorectal disorders. This study aims to evaluate LP reproducibility under water-perfused HRM, provide normal data and new parameters based on 3D and healthy comparison studies under perfusional HRM.MethodsFifty healthy (25 F) underwent water-perfused 36 channel HRM based on LP at resting, squeeze, cough, push, and rectal sensory. Additional 3D manometric parameters were: pressure-volume (PV) 104mmHg2.cm (resting, short and long squeeze, cough); highest and lowest pressure asymmetry (resting, short squeeze, and cough). Complementary parameters (CP) were: resting (mean pressure, functional anal canal length); short squeeze (mean and maximum absolute squeeze pressure), endurance (fatigue rate, fatigue rate index, capacity to sustain); cough (anorectal gradient pressure); push (rectum-anal gradient pressure, anal canal relaxation percent); recto-anal inhibitory reflex (anal canal relaxation percent).ResultsNo difference to genders: resting (LP, CP, and 3D); short squeeze (highest pressure asymmetry); endurance (CP); cough (CP, highest and lowest pressure asymmetry); push (gradient pressure); rectal sensory. Higher pressure in men: short squeeze (maximum incremental, absolute, and mean pressure, PV, lowest pressure asymmetry); long squeeze (PV); cough (anal canal and rectum maximum pressure, anal canal PV); push (anal canal and rectum maximum pressure). Anal canal relaxation was higher in women (push).ConclusionsLP reproducibility is feasible under water-perfused HRM, and comparative studies could bring similarity to dataset expansion. Novel 3D parameters need further studies with healthy and larger data to be validated and for disease comparisons.Key points• London Protocol and Classification allied with the technological evolution of HRM (software and probes) has refined the diagnostic armamentarium in anorectal disorders.• Novel 3D and deepening the analysis of manometric parameters before the London Classification as a contributory diagnostic tool.• Comparison of healthy volunteers according to the London Protocol under a perfusional high-resolution system could establish equivalence points.

Guidewire-assisted placement of water-perfused esophageal high-resolution manometry probe when gastric insertion fails: A single-center experience.

Blind positioning of a high-resolution manometry (HRM) probe across the esophagogastric junction (EGJ) is not always possible. We report our experience using guidewire-assisted water-perfused HRM probe insertion when the EGJ could not be traversed. Retrospective study analyzing the failure rate of EGJ insertion during HRM, and reporting a series of guidewire-assisted procedures. Among 2727 HRM procedures, the failure rate for traversing the EGJ was 2.7% (73 patients). The technique of guidewire-assisted placement of the HRM probe was used in 25 patients; it was well-tolerated and successful in all patients. No motility disorder was found in 6 patients. In four patients with previously diagnosed achalasia, achalasia subtype changed to type III in one patient. While a suspected motility disorder at barium esophagram and/or initial imperfect HRM tracing was confirmed in 10 patients, a new motility disorder was diagnosed in five patients using guidewire-assisted placement of the HRM probe. In cases of inability to traverse the EGJ, insertion of a water-perfused HRM probe using an endoscopically-placed nasogastric guidewire allows successful EGJ and esophageal peristalsis assessment. Although motility disorders are often suspected using alternative diagnostic modalities, guidewire-assisted placement of HRM may be helpful for revealing them in patients where alternative diagnostic modalities are either unavailable or inconclusive.

Effects of phosphodiesterase-5 inhibitor sildenafil on esophageal secondary peristalsis: Studies with high-resolution manometry.

Secondary peristalsis contributes to the clearance of retained refluxate from the esophagus. Sildenafil, a phosphodiesterase-5 inhibitor, inhibits primary esophageal peristalsis, but its effects on secondary peristalsis remain unknown. This study sought to investigate whether sildenafil could influence physiological characteristics of secondary peristalsis by applying high-resolution manometry (HRM). Seventeen healthy volunteers (15 men and 2 women, aged 30.2±6.4years) underwent two HRM studies on separate days following the administration of either a placebo or 50mg of sildenafil in a random order. Both studies were performed using a water-perfused HRM catheter containing one air injection channel positioned in the mid-esophagus. Secondary peristalsis was stimulated by a rapid mid-esophageal injection of 10 or 20mL of air 1h after the administration of either the placebo or sildenafil. The frequency and distal contractile integral of secondary peristalsis were then compared. Complete secondary peristalsis triggered by the 20-mL air injection was more frequent than observed with the 10-mL air injection (P<0.001). The vigor of secondary peristalsis triggered by the injection of either volume of air was lower than that of primary peristalsis (P<0.001). Sildenafil significantly reduced the success rate (P≤0.001) and vigor (P<0.001) of secondary peristalsis relative to the effects of the placebo at both distension volumes. Secondary peristalsis can be successfully triggered by rapid air injection during HRM. Sildenafil reduces both the success rate and the vigor of secondary peristalsis, similar to that seen with primary peristalsis.

NORMAL VALUES OF ESOPHAGEAL HIGH-RESOLUTION MANOMETRY: A BRAZILIAN MULTICENTER STUDY.

The high-resolution manometry has been a significant advance in esophageal diagnostics. There are different types of catheter and systems devices to capture esophageal pressures that generate variable data related to Chicago Classification (CC) and consequently influence normal values results. There are not normative data for the 24-channel water-perfused high-resolution manometry system most used in Brazil with healthy volunteers in supine posture. To determine manometric esophageal normative values for a 24-channel water-perfused high-resolution manometry catheter in supine posture using healthy volunteers according to CC 3.0 parameters. A total of 92 volunteers with no gastrointestinal symptoms or medications affecting GI motility underwent esophageal high-resolution manometry by standard protocol. Age, gender and manometry parameters analyzed using Alacer software were collected. The median, range, and 5th and 95th percentiles (where applicable) were obtained for all high-resolution manometry metrics. Normal value percentiles were defined as 95th integrated relaxation pressure, 5th-100th distal contractile integral, and 5th distal latency. The mean age was 40.5±13.2 years. Our normative metrics were integrated relaxation pressure <16 mmHg and distal contractile integral (708-4111 mmHg.cm.s) distal latency was <6 s and peristaltic break size (>4 cm). For EGJ-CI the range 5th-95th was 21.7-86.9 mmHg.cm.s. This is the first report of normative data for the 24-channel water-perfused system in supine posture. It revealed higher integrated relaxation pressure and distal latency duration which suggest the need to change CC 3.0 cutoffs for this system. It is observed that there is a tendency that DCI >7000 mmHg.cm.s may represent the lower limit of hypercontractility, and when <700 mmHg.cm.s (<5% percentile) interpreted as ineffective esophageal motility or failcontraction. Also compared to Chicago 3.0, higher integrated relaxation pressure and duration of distal latency were found. We emphasize that these data must be confirmed by future studies.

VALIDATION OF A NEW WATER-PERFUSED HIGH-RESOLUTION MANOMETRY SYSTEM.

Water-perfused high resolution manometry system. High-resolution manometry is more costly but clinically superior to conventional manometry. Water-perfused systems may decrease costs, but it is unclear if they are as reliable as solid-state systems, and reference values are interchangeable. To validate normal values for a new water-perfusion high-resolution manometry system. Normative values for a 24-sensors water perfused high-resolution manometry system were validated by studying 225 individuals who underwent high resolution manometry for clinical complaints. Patients were divided in four groups: group 1 - gastroesophageal reflux disease; group 2 - achalasia; group 3 - systemic diseases with possible esophageal manifestation; and group 4 - dysphagia. In group 1, a hypotonic lower esophageal sphincter was found in 49% of individuals with positive 24 h pH monitoring, and in 28% in pH-negative individuals. In groups 2 and 3, aperistalsis was found in all individuals. In group 4, only one patient (14%) had normal high-resolution manometry. The normal values determined for this low-cost water-perfused HRM system with unique peristaltic pump and helicoidal sensor distribution are discriminatory of most abnormalities of esophageal motility seen in clinical practice.

NORMATIVE VALUES FOR A NEW WATER-PERFUSED HIGH RESOLUTION MANOMETRY SYSTEM.

Esophageal manometry is the most reliable method to evaluate esophageal motility. High resolution manometry (HRM) provides topographic contour colored plots (Clouse Plots) with simultaneous analysis from the pharynx to the stomach. Both solid state and water-perfused systems are available. This study aims to determinate the normative data for a new water-perfused HRM. HRM was made in 32 healthy volunteers after 8 hours fasting. HRM system used consisted of a 24-channel water-perfused catheter (Multiplex, Alacer Biomedica, São Paulo, Brazil). The reusable catheter is made of polyvinyl chloride (PVC) with 4.7 mm of diameter. Side holes connected to pressure transducers are spaced 2 cm for the analysis from the pharynx to the lower esophageal sphincter (LES). Holes are spaced 5 mm and 120° in a spiral disposition in the LES area. The sensors encompass 34 cm in total. Upper esophageal sphincter (UES) parameters studied were basal and relaxation pressures. Esophageal body parameters were distal contractile integral (DCI), distal latency (DL) and break. LES parameters studied were basal pressure, integrated residual pressure (IRP), total and abdominal length. Variables are expressed as mean ± standard deviation, median (interquartile range) and percentiles 5-95th. All volunteers (17 males, aged 22-62 years) completed the study and tolerated the HRM procedure well. Percentiles 5-95th range were calculated: Upper Esophageal Sphincter (UES) basal pressure 16.7-184.37 (mmHg), DL: 6.2-9.1 (s), DCI: 82.72-3836.61 (mmHg.s.cm), break: <7.19 (cm), LES basal pressure: 4.89-37.16 (mmHg), IRP: 0.55-15.45 (mmHg). The performance and normative values obtained for this low-cost water-perfused HRM seems to be adequate for clinical use.

Assessment of esophageal function using provocative tests during high resolution manometry: A single-center experience.

Provocative tests were used to provide additional information during performing high resolution manometry (HRM). The study aimed to evaluate whether it is feasible to test esophageal function with different esophageal provocative tests during HRM. 23 healthy volunteers (9 women; mean age 25 years, range 21-30 years) underwent water-perfused HRM. Each subject received 10 liquid swallows, 10 solid swallows, 10 liquid swallows with abdominal compression, and 5 multiple rapid swallowing (MRS). DCI was significantly greater during abdominal compression than that of solid swallows (p=0.025). Compared with liquid swallows, there was a significant decrease in CFV during solid swallows (p=0.04). DL was significantly greater during solid swallows than that of liquid swallows (p<0.001) or abdominal compression (p<0.001). IRP 4s was significantly lower during abdominal compression than that of liquids (p<0.001) or solid swallows (p=0.006). All subjects had complete inhibition during MRS and increased DCI after MRS as compared with liquid swallows (p<0.05). Esophageal provocative test may provide additional utility in performing HRM studies. The data for esophageal provocative tests are distinct from standard liquid swallows.

Nursing experience for patients of esophageal water-perfused high-resolution manometry

Objective To investigate the key points in the nursing work of esophageal water-perfused high-resolution manometry (WHRM). Methods Summarized the nursing experiences before, during and after WHRM of 153 patients. Results Only 5 cases could not finish the test due to failure of intubation. 23 cases complained about nasopharyngeal discomfort but follow-up monitoring was unremarkable. Conclusion In order to ensure the completion of WHRM, nursing cooperation requires serious assessment and preparation before manometry, intimate observation of patients' condition during manometry, and keep the catheter disinfection after manometry. Key words: Esophagus; Manometry; Nursing care

Mo1884 Inter-Rater and Inter-Device Agreement for the Diagnosis of Primary Esophageal Motility Disorders Based on Chicago Classification Between Solid-State and Water-Perfused HRM System -A Prospective, Randomized, Double Blind, Crossover Study

Background:High ResolutionManometry (HRM) is a new technique for intraluminal esophageal pressure measurement that employs an increased number of pressure sensors spaced closely together. Two systems have now become widely available: the 36 solid-state (SS) pressure transducers system, used to create the new Chicago Classification (CC) for Primary Esophageal Motility Disorders, and the recently introduced 24-channel water perfused (WP) system. Comparative data in terms of inter-device pressure parameters variability and diagnostic accuracy are lacking. Aim: To assess and compare normal values for pressure measurements between the 36-SS and the 24-WP HRM systems. Moreover, diagnostic inter-rater and inter-device agreement in a group of patients with esophageal symptoms were assessed. Methods: In this prospective, randomized, double blind, crossover study, 20 healthy volunteers [HVs; 11M/9F; median age 29 (IQR 26-33)] and 20 patients [11M/9F; 48 (43-55)] with esophageal symptoms (i.e. reflux symptoms, chest-pain or dysphagia) underwent HRM with both 36-SS (Given Imaging, Los Angeles, CA) and 24-WP (EB Neuro, Firenze, Italy) systems, in random order. Normal values from HVs were obtained and compared using non-parametric statistical analysis. Two expert reviewers (RS, ES) performed a blindfolded analysis of the patients tracings. Diagnoses based on CC in patients with esophageal symptoms were formulated. Inter-rater and inter-device agreement for each reviewer were evaluated by means of Cohen's k value. Results: As shown in the Figure, there were significant differences between the 2 HRM systems, mainly regarding the measurements of Lower Esophageal Sphincter (LES) and Upper Esophageal Sphincter (UES) basal pressure (p<0.01 and p=0.02, respectively), wave amplitude at 3 cm above the LES (p<0.01) and wave duration at 3, 7 and 11 cm above the LES (p<0.01, p<0.01 and p=0.01, respectively). Almost, all CC parameters were significantly different between the two HRM systems: Integrated Relaxation Pressure (IRP) (p=0.01), Distal Contractile Integral (DCI) (p=0.02) and Distal Latency (DL) (p<0.01). Diagnostic inter-rater agreement was higher for SS system (k=1) than for WP system (k=0,68). Diagnostic inter-device agreement was moderate for both reviewers (k[RS]= 0.5; k[ES]=0.4).Conclusions:Compared to the SS system, theWP technique underestimated almost all pressure measurements, including the CC parameters. This is likely due to the increased compliance of the WP system at low water perfusion rates, leading to poor interrater diagnosis reproducibility and inter-device agreement. By contrast, the SS system appears high reproducible in terms of inter-rater agreement. Thus, caution about the interpretation and application of CC in all HRM systems is recommended.

Water-perfused esophageal high-resolution manometry: normal values and validation

Water-perfused high-resolution manometry (HRM) catheters with 36 unidirectional pressure channels have recently been developed, but normal values are not yet available. Furthermore, the technique has not been validated and compared with solid-state HRM. We therefore aimed to develop normal values for water-perfused HRM and to assess the level of agreement between water-perfused HRM and solid-state HRM. We included 50 healthy volunteers (mean age 35 yr, range 21-64 yr; 15 women, 35 men). Water-perfused HRM and solid-state HRM were performed in a randomized order. Normal values were calculated as 5th and 95th percentile ranges, and agreement between the two systems was assessed with intraclass correlation coefficient (ICC) statistics. The 5th-95th percentile range was 3.0-6.6 cm/s for contractile front velocity (CFV), 141.6-3,674 mmHg·s·cm for distal contractile integral (DCI), 6.2-8.7 s for distal contraction latency (DL), and 1.0-18.8 mmHg for integrated relaxation pressure (IRP 4s). Mean (SD) and ICC for water-perfused HRM and solid-state HRM were 4.4 (1.1) vs. 3.9 (0.9) cm/s, ICC: 0.49 for CFV; 1,189 (1,023) vs. 1,092 (1,019) mmHg·s·cm, ICC: 0.90 for DCI; 7.4 (0.8) vs. 6.9 (0.9) s, ICC: 0.50 for DL; and 8.1 (4.8) vs. 7.9 (5.1), ICC: 0.39 for IRP 4s. The normal values for this water-perfused HRM system are only slightly different from previously published values with solid-state HRM, and moderate to good agreement was observed between the two systems, with only small differences in outcome measures.