Normal Anatomy and Physiology:
Physiologic reflux:
- LES remains actively closed -> opens by relaxation once pharyngeal swallow is initiated
- “unguarded moments” where some of the gastric juices reflux up the esophagus, due to open LES and pressure gradient (higher abdominal pressure than intrathoracic)
- But w\ effective peristalsis, once the bolus moves downwards, the esophagus should be cleared from the gastric juices
Anti-reflux mechanism:
- Efficient esophageal clearance
- Adequately functioning gastric revoir
- Mechanically effective LES
Neural | Hormonal | Drugs | Foods | |
Increase LES tone | Alpha stimulation | Gastrin, motilin | Antacids, cholinergics, domperidone, metoclopramide | __ |
Decrease LES tone | Beta stimulation | Cholecystokinin, estrogen\progesterone, glucagon, somatostatin, secretin | Anticholinergics, barbiturates, CCB, diazepam, meperidine, theophylline | Peppermint, chocolate, caffeine, ethanol, smoking, fatty meals |
Characteristics of LES which maintain its tone:
- Its resting pressure
- Its overall length
- Imagine the stomach as a balloon and the LES as the neck of the balloon
- The more you inflate the balloon (stomach), the shorter the neck (LES) becomes -> higher pressure is required to close it -> which decreases the resting pressure
- Gastric distension can be from over-eating\eating large meals, fatty meals (delay gastric emptying)
- Once the pt feels heartburn -> swallow more, why? Saliva is alkaline (high PH) -> neutralizes the gastric juices -> temporarily relieve the heartburn. But increased\repetitive swallowing of “air” -> bloating, belching, and gastric distention -> further LES dysfunction. VICIOUS CYCLE!
- Its intra-abdominal length that is exposed to the positive pressure (most common defect)
- Why is it important? Periods of increased abdominal pressure (e.g. obesity), the pressure applied to the stomach needs to be the same to a portion of LES to prevent reflux
- Pts w\ hiatal hernia (where the LES is completely intra thoracic) are more liable for reflux
Permanently defective sphincter is defined as:
- Mean resting pressure < 6 mmHg
- Overall length < 2 cm
- Intra-abdominal length < 1 cm
Presentation:
- Typical sx: heartburn, regurgitation, dysphagia
- Atypical sx: cough, wheezing, hoarseness, post-prandial fullness, vomiting, chest pain, asthma, aspiration
1» Heartburn:
- Substernal discomfort, burning in character
- Begins in epigastrium, radiating upwards
- Aggravated by meals, spicy\fatty foods, chocolate, coffee
- Worse in supine position
- Relieved by antacids
2» Regurgitation:
- Effortless return of acid\bitter gastric contests into the chest, pharynx, mouth
- Particularly severe at night when supine, or when bending over
- May result in associated pulmonary sx: cough, hoarseness, asthma, recurrent pneumonia (due to bronchospasm)
3» Dysphagia:
- Sensation of difficulty of food passage from the mouth to stomach
- Can be divided into oropharyngeal and esophageal etiologies
- Can be a sign of underlying malignancy -> investigate thoroughly
- May be accompanied by pain (odynophagia), relieved by passage of bolus
4» Chest pain:
- Exertional chest pain similar to angina
- Difficult\impossible to distinguish between them on clinical grounds only
- Some characteristics which suggest esophageal origin:
- Precipitated by meals
- Occurs at night while supine
- Non-radiating
- Responsive to antacids
- Accompanied by other sx: dysphagia or regurgitation
Complications:
- Combination of refluxed gastric juices and duodenal juice (contains bile and pancreatic secretions) is more noxious than gastric juices alone
1) Esophagitis:
2) Ulcerations, hemorrhage, dysmotility
3) Strictures:
- Luminal stricture develops from submucosal and eventually intramural fibrosis
- Occurs at the site of maximal inflammatory injury (i.e. the columnar-squamous epithelial interface)
- Resistant to dilation
- Incidence has lessened since the introduction of PPI
4) Schatzki’s ring:
- Constrictive band at the squamo-columnar junction
- Composed of fibrotic mucosa and submucosa (not esophageal muscle)
- May result in dysphagia
5) Barret’s esophagus:
- Traditionally, it used to be defined by the presence of columnar mucosa, extending at least 3 cm into the esophagus
- Presently, dx is made given any length of endoscopically identifiable columnar mucosa + on biopsy, proving the presence of intestinal mucosa
- Hallmark of IM? Presence of intestinal goblet cells
- It can lead to ulceration (similar to peptic ulceration, having the same propensity to bleed, penetrate, or perforate)
- Ulcerations and stricture in BE have become less common w\ PPI, unlike the incidence of adenocarcinoma
- Adenocarcinoma:
- 10% of GERD pts develop BE
- Pts of BE, have a lifetime risk of 7% of developing adenocarcinoma
6) Respiratory complications:
- Repetitive aspirations -> recurrent\aspiration pneumonia, asthma, lung abscess, bronchiectasis pulmonary fibrosis
Diagnosis:
-
Upper GI series; barium study:
- Look for anatomical cause for reflux (hiatal hernia)
- Check for pathology resulting from long-standing reflux (ulcer or stricture)
- 40% of pts w\ classical GERD sx -> show spontaneous reflux
- Signs of reflux:
- Abnormal motility -> weakened primary peristalsis
- Mucosal nodularity: in early ds -> due to edema and inflammation
- Thickened folds
- Ulcerations and erosions
-
24-hr ambulatory PH monitoring:
- A probe w\ pH electrodes -> inserted into the pt’s esophagus for 24 hrs
- Gold standard for GERD dx (sensitivity and specificity of 96%)
- Determines the severity of reflux by DeMeester’s parameters
-
Esophageal manometry:
- Evaluates competence of LES
-
Endoscopy (EGD):
- Evaluates mucosa to rule out BE
- Used to biopsy
- Indications:
- Extremes of ages
- Malignancy
- Bleeding
- Chronicity (>5 yrs)
- Failure of medical therapy
- Extra GI sx
Treatment:
1. Non-pharmacological; life-style modification:
- Elevations of the head-end of bed
- Avoid alcohol, coffee, chocolate, peppermint, nicotine
- Eat small, frequent meals
- Avoid tight clothing
- Avoid eating 2-4 hrs before sleep
2. Medical:
- Antacids -> symptomatic relief
- H2 antagonists (ranitidine)
- PPI (omeprazole)
- Pt should undergo a trial of medical therapy for 6-12 wks before further investigation
- Metoclopramide -> promotes gastric emptying, beneficial early in the ds
- Drugs that increase LES pressure: Metoclopramide and bethanechol
3. Surgery:
- Indications:
- If medical management fails
- If pt develops esophageal complications: chronic esophagitis, strictures, ulcers ± BE
- Respiratory complication
- Types of procedures:
- Nissen procedure: the procedure of choice
- 360° fundoplication -> wrapping the fundus of the stomach around the distal portion of the esophagus to create a sphincter (1st line is laparoscopic)
- Works in 85% of pts
- Goals:
- Increase LES tone
- Elongate LES ≈ 3 cm
- Return LES into abdominal cavity
- Post op complications:
- Immediate: pneumothorax, bleeding (short gastric arteries or spleen itself), perforation
- Early (2-4 wks): wound infection, obstructive Sx, cont. reflux, hernia
- Late: gas bloat syndrome (no burping\vomiting), Wt loss, recurrence
- Partial fundoplication:
- 270° fundoplication
- Indicated if poor motility
- e.g.: Belsy (transthoracic) or Toupet (laparoscopic)
Download the PDF version: here
References:
- Dr Albargawi’s clinical notes
- Schwartz’s principles of surgery
- First aid for the surgical clerkship
- Monte Reid
- Surgical recall