Which esophageal sphincter prevents reflux




















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Lower esophageal sphincter function in the cat: role of central innervation assessed by transient vagal blockade. Influence of vagal cooling on esophageal function. Am J Physiol ; :E—E Nature of the vagal inhibitory innervation to the lower esophageal sphincter. J Clin Invest ; 55 — Neural control of the lower esophageal sphincter: influence of the vagus nerves. J Clin Invest ; 54 — Identification of M1 and M2 muscarinic receptor subtypes in the control of the lower esophageal sphincter in the opossum.

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Gut ; 32 Effect of general anaesthesia on transient lower oesophageal sphincter relaxations in the dog. Aust NZ J Surg ; 58 — Effect of cold stress on postprandial lower esophageal sphincter competence and gastroesophageal reflux in healthy subjects. Dig Dis Sci ; 37 — Oesophageal motor function and outcome of treatment with H2—blockers in erosive oesophagitis. J Gastrointest Motil ; 4 — Effect of cisapride on postprandial gastrooesophageal reflux.

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Am J Vetin Res ; 48 — ChemPort Staunton E. Smid SD. Dent J. Blackshaw LA. Triggering of transient LES relaxations in ferrets: role of sympathetic pathways and effects of baclofen. Failure of transient lower oesophageal sphincter relaxation in response to gastric distention in patients with achalasia: evidence for neural mediation of transient lower oesophageal sphincter relaxations. Mechanoreceptors of the proximal stomach: role in triggering transient lower esophageal sphincter relaxation.

Evidence for inhibition of opossum LES through intrinsic gastric nerves. Central motor program for relaxation of periesophageal diaphragm during the expulsive phase of vomiting. Brain Res ; — Gastroenterology ; 4 :A Cholecystokinin and nitric oxide in transient lower esophageal sphincter relaxation to gastric distension in dogs. Muscle relaxants such as Nitrostat nitroglycerin or Procardia nifedipine may help as well.

However, they can be inconvenient, cause unpleasant side effects, and tend to become less effective over time. Hypertensive LES involves increased muscle contraction.

The cause is often unknown, but it is sometimes related to GERD. Symptoms of hypertensive LES often get worse slowly over time. They include:. Treatment is often myotomy, a minimally invasive surgery similar to that used for achalasia.

Diagnostic tests performed for problems related to the lower esophageal sphincter include:. An esophagram is a series of X-rays of the esophagus. It can show problems with the LES, poor esophageal emptying, and the lack of a proper peristaltic wave. Barium is a white, chalky substance that you swallow to make some areas of your body show up better on an X-ray.

Barium esophagrams are often used to diagnose:. In an upper GI endoscopy, or esophagogastroduodenoscopy EGD , the esophagus, stomach, and duodenum are examined with a long, flexible tube called an endoscope. It's inserted through the nose or mouth. This test is considered the gold standard for diagnosing GERD.

It involves hour monitoring of the acid levels in the lower esophagus, near the LES. It involves placing a thin catheter that detects acid in the esophagus. The test reveals how many episodes of high acid you have and how long acid levels are elevated. Esophageal manometry involves a small tube with pressure sensors. The tube measures pressure at different points along the way. That includes the luminal opening pressure in both esophageal sphincters and throughout the esophagus.

This test is most often used when a doctor suspects:. The lower esophageal sphincter is a ring muscle at the point where the esophagus connects to the stomach. Its job is to stop stomach contents from leaking into the esophagus and mouth. If the lower esophageal sphincter doesn't work properly, you can develop conditions like GERD, in which stomach acid moves back up and irritates the esophagus. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.

Cleveland Clinic: healthessentials. Updated November 27, Updated April 5, University of California Los Angeles Health. Updated July 8, Cleveland Clinic.

GERD chronic acid reflux. Updated December 6, Hiatal hernia. Updated January 9, International Foundation for Functional Gastrointestinal Disorders. Disorders of the esophagus. Michigan Medicine. Pneumatic dilation. Heller myotomy. Memorial Hermann Foundation. Hypertensive lower esophageal sphincter. Johns Hopkins Medicine. FAQs about swallowing disorders. National Center for Biotechnology Information, U. National Library of Medicine: StatPearls.

Physiology, lower esophageal sphincter. Updated April 20, Tissue engineering of the gastroesophageal junction. J Tissue Eng Regen Med. Testing also rules out other possible causes of your symptoms. Other less frequently performed tests include the Bernstein test and esophageal manometry.

Although clinical evidence suggests that dietary and lifestyle modifications are usually not sufficient to bring chronic GERD under control, your physician might suggest a number of dietary and lifestyle changes directed at reducing your symptoms, and adhering to these recommendations might provide some relief.

The first goal of treatment is to prevent the reflux of stomach acid into the esophagus. Foods that trigger reflux and its symptoms vary from person to person. By paying close attention to your diet and symptoms, you may be able to identify which foods repeatedly contribute to your reflux. Common trigger foods include alcohol, caffeine, fatty foods, and some spices. Avoiding large portions at mealtime and eating smaller, more frequent meals might aid in symptom control.

Many overweight individuals find symptom relief when they lose some weight, as excess bulk, especially around the abdomen, might put pressure on the digestive tract, negatively affecting its function.

Avoid clothes that fit tightly around the waist, as these also increase abdominal stress. People who have GERD should avoid lying down right after eating and refrain from eating within two to three hours of bedtime. To reduce nighttime symptoms, elevating the head of the bed about six inches may also help, but make sure to do this by propping up the mattress or bed frame, not by using pillows.

Using pillows can lead to back or neck pain and compression on the stomach that could actually increase GERD symptoms.

There are two main approaches to treating GERD with medications: neutralizing acid and blocking its production. Some find that these non-prescription antacids provide quick, temporary, or partial relief but they do not prevent heartburn. Consult your physician if you are using antacids for more than three weeks. Two classes of medication that suppress acid secretion are histamine-2 receptor antagonists H 2 RAs and proton pump inhibitors PPIs.

Treatments that reduce reflux by increasing LES pressure and downward esophageal contractions are metoclopramide and domperidone maleate. All of the medications discussed above have specific treatment regimens, which you must follow closely for maximum effect. Usually, a combination of these measures can successfully control the symptoms of acid reflux.



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