GI Tract & Achalasia Questions

• The GI tract is a 23-26 foot long pathway from the mouth to the anus, including the esophagus, stomach, small and large intestines, and rectum.

Esophagus

• Located in the mediastinum anterior to the spine, and posterior to the trachea and heart.
• It is a hollow, muscular tube about 25 cm (10 in) long
• Passes through the diaphragm via the diaphragmatic hiatus.

Stomach

• Occupies the upper left abdomen under the left liver lobe and the diaphragm, overlying most of the pancreas.
• It is a hollow, muscular organ with ~1500 mL capacity
• Food is stored, digestive fluids secreted and partially digested food (chyme) is propelled into the small intestine.
• The gastroesophageal junction serves as the stomach's inlet.
• Composed of four regions: cardia (entrance), fundus, body, and pylorus (outlet).
• The pyloric sphincter, formed by circular smooth muscle in the pylorus wall, regulates the opening between the stomach and small intestine.

Small Intestine

• The longest segment of the GI tract, accounting for about two-thirds of its total length.
• It folds to provide ~7000 cm² (70 m²) of surface area for secretion and absorption.
• Nutrients enter the bloodstream through its walls.
• It has three sections: duodenum (proximal), jejunum (middle), and ileum (distal).
• The ileum ends at the ileocecal valve, or sphincter, which regulates flow from the ileum into the large intestine's cecal portion.
• It prevents bacterial reflux into the small intestine.
• The vermiform appendix is attached to the cecum and has little or no known physiologic function.
• The common bile duct empties into the duodenum at the ampulla of Vater and allows bile and pancreatic secretions to pass through.

Large Intestine

• Consists of an ascending segment that extends up the right abdomen side.
• A transverse segment extends from right to the left side of the upper abdomen.
• A descending segment is found on the left side of the abdomen.
• The sigmoid colon, rectum, and anus create the terminal portion.
• A network of striated muscle that forms both the internal and external anal sphincters regulates the anal outlet.

GI Tract Blood Supply

• The GI tract receives blood from arteries originating along the thoracic and abdominal aorta.
• Veins return blood from digestive organs and the spleen.
• The portal venous system is made up of 5 large veins: superior mesenteric, inferior mesenteric, gastric, splenic, and cystic veins, making the vena portae that enters the liver.
• Sympathetic and parasympathetic portions of the autonomic nervous system innervates it.
• Sympathetic nerves generally have an inhibitory effect, decreasing gastric secretion, motility, and constricting sphincters and blood vessels.
• Parasympathetic stimulation causes peristalsis and increases secretory activities.
• The sphincters relax under parasympathetic stimulation, except for the upper esophageal and the external anal sphincter, which are under voluntary control.

Primary Functions of the GI Tract

• Absorption into the bloodstream of small nutrient molecules produced by digestion.
• Breakdown of food particles into the molecular form for digestion.
• Elimination of undigested, unabsorbed foodstuffs and other waste products.

Achalasia

• Characterized by absent or ineffective peristalsis of the distal esophagus and failure of the esophageal sphincter to relax during swallowing.
• A rare disorder due to malfunction of nerves controlling food movement through the esophagus.
• It is a motor disorder marked by progressively incomplete relaxation of the lower esophageal sphincter (LES)
• Progressive loss of peristalsis in the esophageal body.

Achalasia Symptoms

• Swallowed food has difficulty passing into the stomach
• The esophagus above the LES becomes enlarged

3 Types of Achalasia

• Jackhammer Achalasia
  • Characterized by minimal contractility in the esophageal body.
  • The esophagus remains quiescent (inactive) and does not contract normally,
  • Display a hypercontractile esophagus
• Panesophageal Achalasia
  • Involves intermittent periods of panesophageal pressurization (simultaneous pressure increase throughout the esophagus).
  • Normal amplitude spasms
• Diffuse Type III Achalasia
  • Premature or spastic distal esophageal contractions.
  • Shows the highest inflammatory response compared to other types.
  • Characterized by LES obstruction.

Achalasia Key Points

• Type III has the worst outcomes compared to other subtypes.
• It often requires longer myotomies or peroral endoscopic myotomy (POEM) for effective treatment
• May progress from other esophageal motility disorders over time.

Achalasia Causes and Pathophysiology

• Unknown cause.
• There is a decrease or absence of peristalsis in the distal esophagus.
• Normal swallowing pattern does not occur.
• Lower esophageal sphincter muscle does not relax,
• Prevents the passage of swallowed food

Achalasia Clinical Manifestations

• Dysphagia is the main symptom, indicated by difficulty with solid foods.
• Other manifestations are regurgitation, chest discomfort, weight loss, and pyrosis.

Achalasia Assessment and Diagnosis

• Barium swallow
• Chest CT
• Endoscopy
• Esophagram
• Esophageal manometry - confirms the diagnosis; the definitive test

Achalasia Treatment

Pharmacologic

• Isosorbide Dinitrate / Calcium Channel Blocker

Botox injection

• Provides easier swallowing
• Lasts for 6-12 months

Pneumatic Dilation

• The narrowed area of the esophagus is stretched
• Perforation is a possible complication

Heller Myotomy

• This is a type of esophagomyotomy
• Involves cutting the esophageal muscle fibers
• Can be performed laparoscopically with or without fundoplication
  • Fundoplication minimizes GERD incidence.

Management

• Achalasia cannot be repaired but can be managed
• Eat slowly
• Increase liquid consumption
• Sit upright while eating and for 1 hour after eating
• Take medications with a full glass of water

Ballon Dilation

• Tears some LES fibers and reaches a predetermined diameter; 75% success rate
• Complications- mediastinal tear, and can correct spasm and stricture

Pneumatic dilation

• Calcium channel blocker – sometimes not effective.
• Potent smooth muscle relaxant that may help in treatment
• Botulism toxin
  • Not good for long term
  • Injected endoscopically into LES fibers to paralyze muscle.
  • Most effective in older clients.
  • The efficacy decreases with repeated treatments because of the development of antibodies by the client.
  • The same medicines with GERD.

Hiatal Hernia

• The upper part of the stomach pushes through the opening in the diaphragm and up into the chest.
• It is the protrusion of the upper part of the stomach.

Hiatal Hernia Causes

• Heavy lifting
• Hard coughing/sneezing
• Pregnancy and delivery
• Vomiting
• Constipation
• Obesity

Pathophysiology

• Esophageal hiatus in the diaphragm has a larger opening.
• Part of the stomach slips/passes through the hiatus and enters into the chest.

Complications of Hiatal Hernia

• Sliding Hiatal Hernia: GERD
• Rolling Hiatal Hernia: Obstruction, Strangulation, and Development of a Volvulus

Types of Hiatal Hernia

• Sliding Hiatal Hernia
  • The junction slides up during times of excess abdominal pressure.
  • Returns to normal placement once relieved
  • The upper stomach and the gastroesophageal junction are displaced upward into the thorax
• Paraoesophageal Hernia
  • Accounts for 90% of all esophageal hernias' total cases.
  • Occurs when all parts of the stomach pushes through the diaphragm beside the esophagus.
  • The stomach remains stuck in the chest with no sliding up or down.
  • The gastroesophageal junction remains below the diaphragm
    • All or part of the stomach pushes through into the thorax.

Clinical Manifestations of a Hiatal Hernia

• Pyrosis
• Regurgitation
• Dysphagia
• Intermittent epigastric pain
• Fullness after eating

Hiatal Hernia Assessment and Diagnosis

• X-ray
• Barium X-ray
• Barium Swallow
• Esophagogastroduodenoscopy (EGD)
• Upper GI endoscopy

Hiatal Hernia Treatment

Pharmacological

• Proton Pump Inhibitor
• Antacid

Surgical

• NISSEN
• Fundoplication

Management

• Frequent small feedings
• Not to recline for 1 hour postprandial
• Culture sensitivity test
• May require 5 days to culture and grow bacteria
  • It can cause infection

Postoperative Assessment

• Assess the wound drainage for any sign of infection
• Clients may have an NG tube
  • Patency of drainage must be maintained to avoid stomach distention.
  • Brown/black in the tube indicates bleeding
  • Dark green/bile indicates the gall bladder is involved.
  • Always close the tube to avoid letting air inside.
  • Use the hard NGT for temporary cases; soft NGT for long-term
• Assess for venous thrombus following these surgeries
  • Thrombus stays in place; an embolus can travel
  • Fat embolism is a major complication for post-op (big bone surgery).

Prevent Respiratory Complication

• Teach patients the importance of coughing and deep breathing after surgery
• This will prevent pneumonia and atelectasis
• Splint incision with a pillow
  • If unable to splint incision with a pillow, cover with wet saline gauze, then inform surgeon
• Incentive spirometry can also be used

Prevent Gas-Bloat Syndrome During a Hiatal Hernia

• Small, frequent meals are provided to avoid overloading the stomach
• Avoid carbonated beverages and gas-producing foods
• Ambulating can assist peristalsis in removing air from the GI tract

Gastroesophageal Reflux Disease (GERD)

• Backflow of gastric or duodenal contents into the esophagus
  • Troublesome symptoms
  • Mucosal injury to the esophagus.
• Excessive reflex may occur due to an incompetent lower esophageal sphincter (LES), pyloric stenosis, or a motility disorder
• Severity increases w/ age
• Manifestations from mild, intermittent to more severe esophageal erosion and stricture
• It can also affect Barrett's esophagus with precancerous changes and esophageal carcinoma.

GERD Causes

• Incompetent LES
• Aging
• CASH (coffee– alcohol – spicy and hot)
• Hiatal Hernia

Risk factors for GERD or chronic acid reflux:

• Smoking
• Large meals or eating late at night
• Consuming triggered foods (fatty foods or fried foods)
• Going to sleep shortly after having a meal
• Drinking alcohol or coffee or soda
• Taking medication without consulting a doctor

GERD Clinical Manifestations

• Regurgitation – Hallmark sign
• Pyrosis
• Dyspepsia
• Dysphagia
• Hypersalivation

GERD Assessment and Diagnosis

• pH monitoring – gold standard
• Documents pathologic acid reflux and correlating events with symptoms.
• Endoscopy
• Barium Swallow
• Esophageal manometry
  • To rule out achalasia or other conditions.
  • Plan surgical approach.
• EGD - esophagogastroduodenoscopy
  • Examine the lining of the esophagus (swallowing tube), stomach, and the upper portion of the small intestine (duodenum)
  • Evaluates mucus for esophagitis, strictures, ulcerations, and anatomical abnormalities

GERD Treatment

Pharmacologic

• Antacid:
  • Typically, the client should take 30mL 1 hour before and 2-3 hours after each meal to buffer or neutralize gastric acid secretions to soothe he mucosal lining.
• H2 Receptor Blocker
  • It inhibits at H2 receptor sites at parietal cells, decreasing gastric acid secretions
  • Given an hour before or after antacids
  • Most effective dose is a twice-daily dosing schedule: first dose in the morning, second dose 1 hour after the evening meal
• Proton-Pump Inhibitors (PPI)
• Given twice daily
• MOST effective in treating GERD, PPIs provide more acid secretion control by inhibiting the hydrogen & potassium ATPase enzyme system in the parietal cells
• Given 30 mins before meals.

Endo Cinch endoluminal gastroplication

• Creating plications (pleats) at the LES; via the endoscope
• The physician places two sutures (stitches) near LES lied together
• Only mild conscious sedation is required
  • Patients can resume normal daily activity the following day

Surgical Management

• Belsey Mark IV Operation
  • Surgeons create esophago-gastric angle
  • 280- wraparound- via thoracic approach

Nissen Fundoplication

• Abdominal approach used
• An increase in pressure or volume into the esophagus
• Surgeon creates a valve-like substitute sphincter in the inherent contractility

Management

• Remain sitting upright
• Semi- Fowler's
• Follow prescribed diet and medication regiment.

Questions about the gastrointestinal tract, its functions, and conditions like achalasia. Includes sympathetic and parasympathetic effects, achalasia diagnosis and treatment, and hiatal hernia. Also explores aspects of esophageal function.