Phrenoesophageal ligament re-visited

Deep Diaphragmatic Breathing-Anatomical and Biomechanical Consideration

Background: Deep diaphragmatic breathing (DDB) involves slow and fully contraction of the diaphragm with expansion of the belly during inhalation, and slow and fully contraction of the abdominal muscles with reduction of the belly during exhalation. It is the key component of the holistic mind-body exercises commonly used for patients with multimorbidity. Purpose: The purpose of this study was to re-visit and address the fundamental anatomical and biomechanical consideration of the DDB with the relevant literature. Method: Peer-reviewed publications from last the 15 years were retrieved, reviewed, and analyzed. Findings: In this article, we described the updated morphological and anatomical characteristics of the diaphragm. Then, we elucidated in a biomechanical approach how and why the DDB can work on the gastrointestinal, cardiopulmonary, and nervous systems as well as on regulating the intra-abdominopelvic pressure and mind-body interaction to coordinate the diaphragm-pelvic floor-abdominal complex for a variety of physical and physiological activities. Conclusion: Understanding of this updated DDB knowledge may help holistic healthcare professionals including holistic nurses provide better patient education and care management during the DDB or DDB-based mind-body intervention time.

Impaired sliding between the lower esophageal sphincter and crural diaphragm (esophageal hiatus) in patients with achalasia esophagus

Swallow-related axial shortening of the esophagus results in the formation of phrenic ampulla in normal subjects; whether it is the case in achalasia esophagus is not known. The goal is to study axial shortening of the esophagus and relative movement between the lower esophageal sphincter (LES) and crural diaphragm (CD) in normal subjects and patients with achalasia. A novel method, isoimpedance contour excursion at the lower edger of LES, as a marker of axial esophageal shortening was validated using X-ray fluoroscopy (n = 5) and used to study axial shortening and separation between the LES and CD during peristalsis in normal subjects (n = 15) and patients with achalasia type 2 esophagus (n = 15). Abdominal CT scan images were used to determine the nature of tissue in the esophageal hiatus of control (n = 15) and achalasia patients (n = 15). Swallow-induced peristalsis resulted in an axial excursion of isoimpedance contours, which was quantitatively similar to the metal clip anchored to the LES on X-ray fluoroscopy (2.3 ± 1.4 vs. 2.1 ± 1.4 cm with deep inspiration and 2.7 ± 0.6 cm vs. 2.7 ± 0.6 cm with swallow-induced peristalsis). Esophageal axial shortening with swallows in patients with achalasia was significantly smaller than normal (1.64 ± 0.5 cm vs. 3.59 ± 0.4 cm, P < 0.001). Gray-level matrix analysis of CT images suggests more "fibrous" and less fat in the hiatus of patients with achalasia. Lack of sliding between the LES and CD explains the low prevalence of hiatus hernia, and low compliance of the LES in achalasia esophagus, which likely plays a role in the pathogenesis of achalasia.NEW & NOTEWORTHY Swallow-related axial shortening of the esophagus is reduced, and there is no separation between the lower esophageal sphincter and crural diaphragm (CD) with swallowing in patients with achalasia esophagus. Fat in the hiatal opening of the esophagus appears to be replaced with fibrous tissue in patients with achalasia, resulting in tight anchoring between the LES and CD. The above findings explain low prevalence of hiatus hernia and the low compliance of the LES in achalasia esophagus.

Reconstruction of the phreno-esophageal ligament (R-PEL) prevents the intrathoracic migration (ITM) after concomitant sleeve gastrectomy and hiatal hernia repair

BACKGROUND

Laparoscopic Sleeve Gastrectomy (LSG) is the most attractive bariatric procedure, but the postoperative intrathoracic gastric migration (ITM) and "de novo" GERD are major concerns. The main objective of our study was to evaluate the efficiency of the concomitant HHR with or without partial reconstruction of phreno-esophageal ligament (R-PEL) to prevent ITM after LSG. The secondary objectives focused on procedure's metabolic and GERD-related outcomes.

PATIENTS AND METHOD

Consecutive patients who underwent primary LSG and concomitant HHR were included in a single-center prospective study. According to the HHR surgical technique, two groups were analyzed and compared: Group A included patients receiving crura approximation only and Group B patients with R-PEL. The patients' evolution of co-morbidities, GERD symptoms, radiologic, and endoscopic details were prospectively analyzed.

RESULTS

Two hundred seventy-three patients undergoing concurrent HHR and LSG were included in the study (Group A and B, 146 and 127 patients) The mean age and BMI were 42.6 ± 11.3 and 43.4 ± 6.8 kg/m². The 12-month postoperative ITM was radiologically found in more than half of the patients in Group A, while in group B, the GEJ's position appeared normal in 91.3% of the patients, meaning that R-PEL reduced 7 times the rate of ITM. The percentage of no-improvement and "de novo" severe esophagitis (Los Angeles C) was 4 times higher in group A 3.4% vs. 0.8% with statistical significance, and correlated to ITM. The GERD symptoms were less frequent in Group B vs Group A, 21.3% vs 37%, with statistical significance. No Barrett's esophagus and no complication were recorded in any of the patients.

CONCLUSION

Concurrent LSG and HHR by crura approximation only has a very high rate of ITM in the first postoperative year (over 50%). R-PEL is an innovative technique which proved to be very efficient in preventing the ITM after HHR.

Botox injection into the lower esophageal sphincter induces hiatal paralysis and gastroesophageal reflux

Endoscopic intrasphincteric injection of Botox (ISIB) is used routinely for the treatment of achalasia esophagus and other spastic motor disorders. Studies show that the ISIB reduces the smooth muscle lower esophageal sphincter (LES) pressure. The esophageal hiatus, formed by the right crus of diaphragm, surrounds the cranial half of the LES and works like an external LES. We studied the effects of ISIB on the LES and hiatal contraction and gastroesophageal reflux (GER). Fourteen patients treated with ISIB were studied. Esophageal manometry-impedance recordings were performed before and after the ISIB. Hiatal contraction was assessed during tidal inspiration, forced inspiration, Müller's maneuver, and straight leg raise. In 6 subjects, the manometry were repeated 6-12 mo after the ISIB. The esophagogastric junction (EGJ) pressure was measured at end expiration (LES pressure) and at the peak of maneuvers (hiatal contraction). Transdiaphragmatic pressure (pdi; force of diaphragmatic contraction) was measured at the peak of forced inspiration. GER was measured from the impedance recordings. The EGJ pressure at end expiration (LES pressure) decreased significantly after the Botox injection. The peak EGJ pressure at tidal inspiration, forced inspiration, Müller's maneuver, and straight leg raise was also dramatically reduced by the ISIB. There was no effect of Botox on the pdi during forced inspiration. Seven of 10 subjects demonstrated GER during maneuvers following the ISIB. Six to 12 mo after ISIB, the LES and hiatal contraction pressure returned to the pre-ISIB levels. ISIB, in addition to decreasing LES pressure, paralyzes the esophageal hiatus (crural diaphragm) and induces GER.NEW & NOTEWORTHY The sphincter mechanism at the lower end of the esophagus comprises smooth muscle lower esophageal sphincter (LES) and skeletal muscle crural diaphragm (hiatus). Current thinking is that the endoscopic intrasphincteric injection of Botox (ISIB), used routinely for the treatment of achalasia esophagus, reduces LES pressure. Our study shows that ISIB, even though injected into the LES, diffuses into the hiatus and causes its paralysis. These findings emphasize the importance of esophageal hiatus as an important component of the antireflux barrier and that the ISIB is refluxogenic.

Laparoscopic Approach to Paraesophageal Hernia Repair

The introduction of minimally invasive techniques to the field of foregut surgery has revolutionized the surgical approach to giant paraesophageal hernia repair. Laparoscopy has become the standard approach in patients with giant paraesophageal hernia because it has been shown to be safe and is associated with lower morbidity and mortality when compared with various open approaches. Specifically, it has been associated with decreased intraoperative blood loss, decreased complications, and reduced hospital length of stay. This is despite a rise in comorbid conditions associated with this patient population. This article describes our operative approach to laparoscopic giant paraesophageal hernia repair.

Esophagojejunostomy With Linear Staplers in Laparoscopic Total Gastrectomy: Experience With 168 Cases in 5 Consecutive Years

PURPOSE

We evaluate surgical outcomes of intracorporeal esophagojejunostomy in laparoscopic total gastrectomy using 2 linear stapler methods.

MATERIALS AND METHODS

The functional end-to-end anastomosis (FEEA) method was chosen as a first choice. The overlap method was chosen in cases with esophageal invasion. We retrospectively analyzed the early and late surgical outcomes of consecutive 168 laparoscopic total gastrectomy cases from April 2011 to December 2016.

RESULTS AND CONCLUSIONS

The FEEA method was selected in 120 cases, and the overlap method was selected in 48 cases. The mean time of esophagojejunostomy for the FEEA and overlap method was 13.2 and 36.5 minutes, respectively. Two cases with FEEA method and 3 cases with overlap method experienced complications due to esophagojejunostomy leakage. These cases were treated without performing a reoperation. One case with FEEA method was complicated due to esophagojejunostomy stenosis. This case was endoscopically treated. Our procedures are safe and feasible.

Low back pain and gastroesophageal reflux in patients with COPD: the disease in the breath

COPD is a worsening condition that leads to a pathologic degeneration of the respiratory system. It represents one of the most important causes of mortality and morbidity in the world, and it is characterized by the presence of associated comorbidity. This article analyzes gastroesophageal reflux disease (GERD) and low back pain (LBP) in patients with COPD and tries to produce anatomo-clinical considerations on the reasons of the presence of these comorbidities. The considerations of the authors are based on the anatomic functions and characteristics of the respiratory diaphragm that are not always considered, from which elements useful to comprehend the symptomatic status of the patient can be deduced, finally improving the therapeutic approach. The information contained in the article can be of help to the clinician and for physiotherapy, and to all health professionals who gravitate around the patient’s care, improving the approach to the diaphragm muscle.

Scary gas: pathways in the axial body for soft tissue gas dissection (part I)

Gas is often encountered in abnormal locations in the torso, including within soft tissue compartments, vessels, and bones. The clinical significance of this gas ranges from incidental, benign, and self-limited to aggressive infection requiring immediate surgery. As a result of fascial interconnectivity and pressure differences between compartments, gas can dissect distant from its source. Gas can easily dissect between spaces of the extrapleural thorax, subperitoneal abdomen, deep cervical spaces, and subcutaneous tissues. The pleural and peritoneal cavities are normally isolated but may communicate with the other spaces in select situations. Dissection of gas may cause confusion as to its origin, potentially delaying treatment or prompting unnecessary and/or distracting workup and therapies. The radiologist might be the first to suggest and identify a remote source of dissecting gas when the clinical manifestation alone might be misleading. The purpose of this paper, the first in a three-part series on soft tissue gas, is to explore the various pathways by which gas dissects through the superficial and deep compartments of the torso.

Artificial phrenoesophageal ligament. An experimental study in dogs

This report deals with the preparation of a 'true' artificial phrenoesophageal ligament aimed at restoring effective anchoring of the esophagus to the diaphragm, keeping the esophagogastric sphincter in the abdomen. A total of 24 mongrel dogs were assigned to four groups: (i) Group I (n = 4): the esophageal diaphragm hiatus left wide open; (ii) Group II (n = 8): the anterolateral esophagus walls were attached to the diaphragm by the artificial ligament and the esophageal hiatus was left wide opened; (iii) Group III (n = 5): in addition to the use of the artificial ligament, the esophageal hiatus was narrowed with two retroesophageal stitches; (iv) Group IV (n = 7): the only procedure was the esophageal hiatus narrowing with two retroesophageal stitches. The phrenoesophagogastric connections were released, sparing the vagus nerves. Five animals of groups III and IV, which did not develop hiatal hernia, were submitted to esophageal manometry immediately before and 15 days after surgery. In group I, all animals developed huge sliding hiatal hernias. In group II, two dogs (25%) had a paraesophageal hernia between the two parts of the artificial ligament. In group III, neither sliding hiatal hernia nor paraesophageal hernia occurred. In group IV, two animals (28.6%) developed sliding esophageal hiatus hernia. Regarding esophageal manometry, postoperative significant difference between groups III and IV (P = 0.008) was observed. Thus, the artificial phrenoesophageal ligament maintained the esophagus firmly attached to the diaphragm in all animals and the esophagogastric sphincter pressure was significantly higher in this group.

Mesoesophagus and other fascial structures of the abdominal and lower thoracic esophagus: a histological study using human embryos and fetuses

A term "mesoesophagus" has been often used by surgeons, but the morphology was not described well. To better understand the structures attaching the human abdominal and lower thoracic esophagus to the body wall, we examined serial or semiserial sections from 10 embryos and 9 fetuses. The esophagus was initially embedded in a large posterior mesenchymal tissue, which included the vertebral column and aorta. Below the tracheal bifurcation at the fifth week, the esophagus formed a mesentery-like structure, which we call the "mesoesophagus," that was sculpted by the enlarging lungs and pleural cavity. The pneumatoenteric recess of the pleuroperitoneal canal was observed in the lowest part of the mesoesophagus. At the seventh week, the mesoesophagus was divided into the upper long and lower short parts by the diaphragm. Near the esophageal hiatus, the pleural cavity provided 1 or 2 recesses in the upper side, while the fetal adrenal gland in the left side was attached to the lower side of the mesoesophagus. At the 10th and 18th week, the mesoesophagus remained along the lower thoracic esophagus, but the abdominal esophagus attached to the diaphragm instead of to the left adrenal. The mesoesophagus did not contain any blood vessels from the aorta and to the azygos vein. The posterior attachment of the abdominal esophagus seemed to develop to the major part of the phrenoesophageal membrane with modification from the increased mass of the left fetal adrenal. After postnatal degeneration of the fetal adrenal, the abdominal esophagus might again obtain a mesentery. Consequently, the mesoesophagus seemed to correspond to a small area containing the pulmonary ligament and aorta in adults.

Pathophysiology of gastroesophageal reflux disease

The gastroesophageal junction is structurally complex and functionally designed to ensure the acid secreted by the most proximal gastric mucosa flows towards the stomach and not up onto the oesophageal squamous mucosa. The pattern and mechanism of reflux vary with the severity of reflux disease and this probably represents different ends of a spectrum rather than distinct pathophysiological mechanisms. Nearly all patients with severe reflux disease have hiatus hernia, however, a substantial proportion of patients with mild reflux disease do not, and this may be a result of intermittent or partial hiatus hernia undetectable by current available tools. The acid pocket is an area of post-prandial unbuffered gastric acidity immediately distal to the gastroesophageal junction and which is enlarged in patients with hiatus hernia. The acid pocket provides a reservoir of acid available to reflux when the intrinsic sphincter fails. Central obesity is an important factor in the aetiology of reflux and does this by the increased abdomino-thoracic pressure gradient inducing hiatus hernia and increasing the rate of flow of reflux when sphincter opens. Central obesity also induces short segment intrasphincteric reflux and thereby columnar metaplasia of the most distal oesophagus.

Measuring movement and location of the gastroesophageal junction: research and clinical implications

Understanding the physiology of gastroesophageal junction (GEJ) is important as failure of its function is associated with reflux disease, hiatus hernia, and cancer. In recent years, there have been impressive developments in high resolution technologies allowing measurement of luminal pressure, pH, and impedance. One obvious deficiency is the lack of technique to monitor the movement and location of the GEJ over a prolonged period of time. Proximal movement of the GEJ during peristalsis and transient lower esophageal sphincter relaxations (TLESRs) is due to shortening of the longitudinal muscle of the esophagus. Techniques for measuring shortening include fluoroscopic imaging of mucosal clip, high-frequency intraluminal ultrasound, and high resolution manometry, but these techniques have limitations. Short segment reflux is recently found to be more common than traditional reflux and may account for the high prevalence of intestinal metaplasia and cancer seen at GEJ. While high resolution pHmetry is available, there is no technique that can reliably and continuously measure the position of the squamocolumnar junction. A new technique is recently reported allowing a precise and continuous measurement of the GEJ based on the principle of Hall effect. Reported studies have validated its accuracy both on the bench and against the gold standard, fluoroscopy. It has been used alongside high resolution manometry in studying the behavior of the GEJ during TLESRs and swallows. While there are challenges associated with this new technique, there are promising ongoing developments. There is exciting time ahead in research and clinical applications for this new technique.

Kinetics of transient hiatus hernia during transient lower esophageal sphincter relaxations and swallows in healthy subjects

BACKGROUND

Proximal displacement of the gastro-esophageal junction (GEJ) is present in hiatus hernia but also occurs transiently during transient lower esophageal sphincter relaxations (TLESRs) and swallows. Using a novel magnetic-based technique we have performed detailed examination of the GEJ movement during TLESRs and swallows in healthy subjects.

METHODS

In 12 subjects, a magnet was endoscopically clipped to the GEJ and combined assembly of Hall-Effect locator probe and 36 channel high-resolution manometer passed nasally. After a test meal the subjects were studied for 90 min.

KEY RESULTS

The median amplitude of proximal movement of GEJ during TLESRs was 4.3 cm (1.6-8.8 cm) and this was substantially greater than during swallowing at 1.2 cm (0.4-2.7 cm), P = 0.002. With both TLESRs and swallows proximal GEJ movement coincided with lower esophageal sphincter (LES) relaxation and return to its original position occurred 4 s after return of LES tone. Kinetic modeling of the movement of the GEJ during TLESRs indicated two return phases with the initial return phase having the greater velocity (0.9 cm s(-1) ) and being strongly correlated with amplitude of proximal movement (r = 0.8, P < 0.001).

CONCLUSIONS & INFERENCES

The marked proximal GEJ migration during TLESRs represents very severe herniation of the GEJ. The rapid initial return of the GEJ following TLESRs when the crural diaphragm is relaxed and its correlation with amplitude suggest it is due to elastic recoil of the phreno-esophageal ligament. The marked stretching of the phreno-esophageal ligament during TLESRs may contribute to its weakening and development of established hiatus hernia.

Hiatal hernias

Esophageal hiatal hernias have been reported to affect anywhere from 10 to 50% of the population. Hiatal hernias are characterized by a protrusion of the stomach into the thoracic cavity through a widening of the right crus of the diaphragm. There are four types of esophageal hiatal hernias: sliding (type I), paraesophageal (type II), and combined (type III), which include elements of types I and II, and giant paraesophageal (type IV). Each type may present with different symptoms and complications. The potential severity of symptoms necessitates proper and prompt diagnosis. Diagnosis is established with the use of barium swallow on chest radiographs. Treatment for sliding hernias involves laparoscopic fundoplication. The aim of our paper is to review the extensive literature regarding hiatal hernias in an effort to enhance awareness and diagnosis of this pathology.

Laparoscopic sphincter augmentation device eliminates reflux symptoms and normalizes esophageal acid exposure: one- and 2-year results of a feasibility trial

OBJECTIVES

One- and 2-year evaluation of a feasibility trial (clinicaltrials.gov registration numbers NCT01057992, NCT01058070, and 01058564) to assess the safety and efficacy of a laparoscopically implanted sphincter augmentation device for the treatment of gastroesophageal reflux disease (GERD).

METHODS

A sphincter augmentation device (LINX Reflux Management System; Torax Medical, Shoreview, MN), designed to prevent reflux due to abnormal opening of the lower esophageal sphincter (LES), was laparoscopically implanted at the gastroesophageal junction in 44 patients. At baseline, all patients had abnormal esophageal acid exposure on 24-hour pH monitoring and improved, but persistent, typical GERD symptoms while on acid suppression therapy with proton pump inhibitors (PPIs). The device comprises a miniature string of interlinked titanium beads, with magnetic cores, placed around the gastroesophageal junction. The magnetic bond between adjacent beads augments sphincter competence. The beads temporarily separate to accommodate a swallowed bolus, allow belching or vomiting, and reapproximate to augment the LES in the closed position. Patients were evaluated after surgery by GERD Health-Related Quality of Life symptom score, PPI usage, endoscopy, esophageal manometry, and 24-hour esophageal pH monitoring.

RESULTS

The total mean GERD Health-Related Quality of Life symptom scores improved from a mean baseline value of 25.7 to 3.8 and 2.4 at 1- and 2-year follow-up, representing an 85% and 90% reduction, respectively (P < 0.0001). Complete cessation of PPI use was reported by 90% of patients at 1 year and by 86% of patients at 2 years. Early dysphagia occurred in 43% of the patients and self-resolved by 90 days. One device was laparoscopically explanted for persistent dysphagia without disruption of the anatomy or function of the cardia. There were no device migrations, erosions, or induced mucosal injuries. At 1 and 2 years, 77% and 90% of patients had a normal esophageal acid exposure. The mean percentage time pH was less than 4 decreased from a baseline of 11.9% to 3.1% (P < 0.0001) at 1 year and to 2.4% (P < 0.0001) at 2 years. Patient satisfaction was 87% at 1 year and 86% at 2 years.

CONCLUSIONS

The new laparoscopically implanted sphincter augmentation device eliminates GERD symptoms without creating undue side effects and is effective at 1 and 2 years of follow-up.

Three-dimensional high-resolution reconstruction of the human gastro-oesophageal junction

The aim of this study was to obtain detailed information regarding the three-dimensional structure of the gastro-oesophageal region, and, in particular, the fiber orientation of the different muscle layers of the junction. This was achieved by a study of an en bloc resection of the gastro-oesophageal junction (GOJ) harvested from a human cadaver. The excised tissue block was suspended in a cage to preserve anatomical relationships, fixed in formalin and embedded in wax. The tissue block was then processed by a custom-built extended-volume imaging system to obtain the microstructural information using a digital camera which acquires images at a resolution of 8.2 microm/pixel. The top surface of the tissue block was sequentially stained and imaged. At each step, the imaged surface was milled off at a depth of 50 microm. The processing of the tissue block resulted in 650 images covering a length of 32.25 mm of the GOJ. Structures, including the different muscle and fascial layers, were then traced out from the cross-sectional images using color thresholding. The traced regions were then aligned and assembled to provide a three-dimensional representation of the GOJ. The result is the detailed three-dimensional microstructural anatomy of the GOJ represented in a new way. The next stage will be to integrate key physiological events, including peristalsis and relaxation, into this model using mathematical modeling to allow accurate visual tools for training health professionals and patients.

Magnetic augmentation of the lower esophageal sphincter: results of a feasibility clinical trial

BACKGROUND

The high prevalence of gastroesophageal reflux disease continues to encourage the development of treatment modalities to fill the gap between acid-suppression therapy and the laparoscopic Nissen fundoplication. The Magnetic Sphincter Augmentation device has been designed to augment the lower esophageal sphincter barrier using magnetic force. A multi-center feasibility trial was done to evaluate safety and efficacy.

METHODS

Patients with typical heartburn (at least partially responding to proton-pump inhibitors), abnormal esophageal acid exposure, and normal esophageal peristalsis were enrolled. Patients with hiatal hernia >3 cm were excluded from the study. The device was implanted laparoscopically around the distal esophagus.

RESULTS

Over a 1-year period, 38 out of 41 enrolled patients underwent this procedure in 3 hospitals. No operative complications were recorded. A free diet was allowed since post-operative day one, and 97% of patients were discharged within 48 h. The mean follow-up was 209 days (range 12-434 days). The GERD-HRQL score decreased from 26.0 to 1.0 (p < 0.005). At 3 months post-operatively, 89% of patients were off anti-reflux medications, and 79% of patients had a normal 24-h pH test. All patients preserved the ability to belch. Mild dysphagia occurred in 45% of patients. No migrations or erosions of the device occurred.

CONCLUSIONS

Laparoscopic implant of the MSA device is safe and well tolerated. It requires minimal surgical dissection and a short learning curve compared to the conventional Nissen fundoplication.

An anatomically based mathematical model of the gastroesophageal junction

In this study the construction of an initial three-dimensional anatomically based mathematical model of the esophagus is presented. The aim of this model is to provide a framework with which to examine the functional behavior of the esophagus and the lower esophageal sphincter during swallowing. Anatomical data from the Visible Human Project was used to provide the outlines of the regions of interest. A C/sup 1/ continuous cubic Hermite finite element mesh was then created using an iterative finite element linear fitting process to an RMS error less than 1 mm. Muscular fiber information was embedded within the model using data from published literature. There is a current lack of detailed microstructural data on the gastroesophageal junction. We describe the specialist measurement rig that we propose to use to obtain the microstructural information in our experimental studies.

Pharmacological dissection of the human gastro-oesophageal segment into three sphincteric components

Quantifications of gastro-oesophageal anatomy in cadavers have led some to identify the lower oesophageal sphincter (LOS) with the anatomical gastric sling-clasp fibres at the oesophago-cardiac junction (OCJ). However, in vivo studies have led others to argue for two overlapping components proximally displaced from the OCJ: an extrinsic crural sphincter of skeletal muscle and an intrinsic physiological sphincter of circular smooth-muscle fibres within the abdominal oesophagus. Our aims were to separate and quantify in vivo the skeletal and smooth muscle sphincteric components pharmacologically and clarify the description of the LOS. In two protocols an endoluminal ultrasound-manometry assembly was drawn through the human gastro-oesophageal segment to correlate sphincteric pressure with the anatomic crus. In protocol I, fifteen normal subjects maintained the costal diaphragm at inferior/superior positions by full inspiration/expiration (FI/FE) during pull-throughs. These were repeated after administering atropine to suppress the cholinergic smooth-muscle sphincter. The cholinergic component was reconstructed by subtracting the atropine-resistant pressures from the full pressures, referenced to the anatomic crus. To evaluate the extent to which the cholinergic contribution approximated the full smooth-muscle sphincter, in protocol II seven patients undergoing general anaesthesia for non-oesophageal pathology were administered cisatracurium to paralyse the crus. The smooth-muscle sphincter pressures were measured after lung inflation to approximate FI. The cholinergic smooth-muscle pressure profile in protocol I (FI) matched closely the post-cisatracurium smooth-muscle pressure profile in protocol II, and the atropine-resistant pressure profiles correlated spatially with the crural sling during diaphragmatic displacement. Thus, the atropine-resistant and cholinergic pressure contributions in protocol I approximated the skeletal and smooth muscle sphincteric components. The smooth-muscle pressures had well-defined upper and lower peaks. The upper peak overlapped and displaced rigidly with the crural sling, while the distal peak separated from the crus/upper-peak by 1.1 cm between FI and FE. These results suggest the existence of separate upper and lower intrinsic smooth-muscle components. The 'upper LOS' overlaps and displaces with the crural sling consistent with a physiological LOS. The distal smooth-muscle pressure peak defines a 'lower LOS' that likely reflects the gastric sling/clasp muscle fibres at the OCJ. The distinct physiology of these three components may underlie aspects of normal sphincteric function, and complexity of sphincter dysfunction.

The effect of anchoring suture on the anastomotic blood flow in a rat model of human esophagojejunostomy

PURPOSE

An impairment of anastomotic blood flow (ABF) and the resulting hypoxia readily lead to the complications such as leakage and stricture. We performed an animal study to evaluate the effect of anchoring suture for minimizing the impairment of ABF caused by tensile loading.

MATERIALS AND METHODS

An end-to-side jejunojejunostomy was done in 20 rats, and this followed the modeling of a human end-to-side esophagojejunostomy. Laser Doppler flowmetry was checked in three different tensile conditions to evaluate the influence of anchoring suture on the ABF.

RESULTS

Before anchoring suture, the mean ABF was 129.06 perfusion unit (PU), 96.99 PU, and 69.04 PU, in the order of tensile stress. After anchoring suture, the mean ABF was 121.68, 103.30, and 87.06 PU (P < 0.01).

CONCLUSION

Anchoring suture is a novel method to reduce the impairment of the anastomotic blood flow that is caused by tension.