GI

The gastrointestinal (GI) tract, or alimentary canal, digests, transports, absorbs nutrients, and eliminates waste. It's a long muscular tube from mouth to anus, including the pharynx, esophagus, stomach, small intestine, and large intestine.

• Vomiting coffee grounds or black stool indicates an emergency.

• Mouth/Buccal Cavity: Includes inner cheek and gums.

• Tongue: Contains taste buds and moves the bolus.

• Salivary Glands: Produce salivary amylase to break down starches. Includes parotid, sublingual, and submandibular glands. Lubricates for speech and chewing, producing 1-1.5 quarts of saliva daily.

• Teeth: Mastication breaks down food for easy swallowing.

• Hard Palate: Separates mouth and nasal cavity.

• Soft Palate: Separates mouth and nasopharynx.

• Uvula: Prevents food from entering nasopharynx during swallowing.

Digestion starts in the mouth.

• Pharynx: The throat where food mixes with saliva to form a bolus. The epiglottis closes during swallowing.

  • Peristalsis moves the bolus to the stomach via the esophagus.

• Stomach: Receives food from the esophagus. Rugae line the stomach. The cardiac sphincter is between the esophagus and stomach, while the pyloric sphincter is between the stomach and small intestine. Holds food for 1-4 hours, creating chyme.

  • Gastric juice contains HCl acid (kills bacteria, aids iron absorption, activates pepsin), pepsin (breaks down protein), lipase (breaks down fats), and intrinsic factor (digests vitamin B12).

• Small Intestine: About 20 ft long. Most chemical digestion occurs here.

  • Duodenum: 9-12 inches long. Bile (from gallbladder and liver) emulsifies fats. Pancreatic juice breaks down sugars.

  • Jejunum: About 8 ft long.

  • Ileum: 12-13 ft long, connects to the large intestine at the cecum. Digestion completes here, with products absorbed into the blood via villi.

• Large Intestine: 4.5 ft long. Divided into cecum (with appendix), ascending colon, transverse colon, descending colon, sigmoid colon, rectum, anal canal, and anus.

  • No digestive enzymes are secreted here. Vitamins are reabsorbed, complex CHO are broken down by bacteria, and water is absorbed to maintain balance. Indigestible materials are stored here. Absorption of B vitamins and vitamin K occurs.

• Appendix: Function unknown; inflammation requires surgery.

• Liver: Large gland below the diaphragm.

  • Functions: Controls protein and sugar levels in blood, stores glycogen, iron, and vitamins. Produces blood proteins (prothrombin, fibrinogen), cholesterol, and bile (emulsifies fats). Detoxifies substances and destroys bacteria.

• Gallbladder: Under the liver, stores about 2 oz of bile and releases it into the small intestine via the common bile duct.

• Pancreas: Behind the stomach.

  • Produces digestive enzymes (exocrine): trypsin, chymotrypsin (for protein), and lipase (for fats).

  • Produces insulin and glucagon (endocrine).

  • Sends pancreatic juices to the duodenum to aid digestion.

• Aging Changes:

  • Decreased taste buds and digestive enzymes.

  • Loss of bowel tone and slower peristalsis.

  • Slower nutrient absorption and decreased chewing capacity.

Diseases

Anal Fissure

Description: Anal fissure is a small tear in the lining of the anus which usually causes bleeding during bowel movements and is typically painful.

Patient's complaints of:

• Anal Fissure

  Description: Anal fissure is a small tear in the lining of the anus which usually causes bleeding during bowel movements and is typically painful.

  Patient's complaints of:

  • Pain during bowel movements

  • A crack in the skin around or near the anus

  • Blood on the stool during bowel movements

  • Pain to lower back and constipation

  Treatment: Involves softening stool

  • Stool softeners to not feel as much pain when passing stool

  • Adjust diet by drinking more water and avoiding spicy foods

  • If nothing is helping surgery would need to be required

  In the event that the fissure does not heal within 8 weeks it may be considered chronic and may need serious treatment. Once a patient has already had a fissure they are now more prone to it meaning they can get it again. An unhealed Fissure may require surgery for the amount of discomfort it causes.

• Celiac Disease

  Celiac disease is an autoimmune disorder triggered by gluten(which is a protein found in wheat, barley, and rye), that damages the small intestine. When a person with Celiac disease eats gluten, their immune system attacks the small intestine, leading to inflammation and damage. This damage prevents the body's ability to absorb nutrients, causing malabsorption ad other health problems.

  Lining of the small intestine

• Cellac disease

  U Pt Complaints:

  Celiac disease symptoms can vary widely, affecting digestion, skin, and even the nervous system; in children, these symptoms may include frequent diarrhea, failure to thrive, and developmental delays, while adults might experience fatigue, weight loss, and abdominal pain; a distinctive skin rash called dermatitis herpetiformis can also be a symptom associated with celiac disease.

  Interesting fact.

  People with Celiac disease may have lactose as well as fructose intolerance, which can be diagnosed by a hydrogen breath test.

Celiac Disease

• Autoimmune disorder triggered by gluten (protein in wheat, barley, and rye).

• Damages the small intestine.

• Immune system attacks the small intestine when gluten is ingested, leading to inflammation and damage.

• Prevents nutrient absorption, causing malabsorption and other health problems. *Symptoms Vary:

  • Affects digestion, skin, and nervous system.

  • In children: frequent diarrhea, failure to thrive, developmental delays.

  • In adults: fatigue, weight loss, abdominal pain.

  • Dermatitis herpetiformis (skin rash).

• Interesting Fact:

  • People with Celiac disease may have lactose and fructose intolerance, diagnosed by a hydrogen breath test.

Crohn's Disease

• Inflammatory bowel disease (IBD) causing swelling and irritation of the digestive tract tissues, usually due to abnormal immune system reactions.

• Commonly affects the end of the small intestine and the beginning of the large intestine but can affect any part of the digestive system.

• Symptoms:

  • Diarrhea, fever, fatigue, belly pain, stomach cramps, bloody stool, mouth sores, reduced appetite, weight loss.

  • Pain or drainage near the anus due to a fistula.

  • Inflammation of skin, eyes, joints, bile ducts, or liver.

  • Anemia and renal calculus.

• Facts:

  • Commonly develops around age 30.

  • Cigarette smoking increases risk.

  • NSAIDs can worsen Crohn's disease.

  • Chronic, no cure.

  • Higher possibility among those of Jewish descent.

  • Increased risk of cancer.

  • Reducing stress and good sleeping habits can reduce flares.

  • Crohn's disease is different for everyone.

GERD (Gastroesophageal Reflux Disease)

• Stomach acid flows back into the esophagus, irritating its lining (acid reflux).

• Most people manage with medication and rest.

• Symptoms:

  • Heartburn.

  • Upper belly or chest pain.

  • Dysphagia (difficulty swallowing).

  • Nighttime acid reflux.

  • Ongoing cough and laryngitis (inflammation of vocal cords).

• Causes:

  • Frequent acid reflux, backwash of food.

• Risk Factors:

  • Obesity, bulging of the top of the stomach, pregnancy, delayed stomach emptying, connective tissue disorders (e.g., scleroderma).

• Aggravating Factors:

  • Smoking, large or late meals, oily/fatty foods, alcohol, medications like aspirin.

• Complications:

  • Inflammation or narrowing of the esophagus.

Diverticulosis/Diverticulitis

• Diverticulosis: Small pouches (diverticula) form on the inside lining of the large intestine due to food/waste pushing against weak spots.

• Diverticulitis: One or more pouches become inflamed.

• Symptoms of Diverticulitis: Lower abdominal pain or fever.

• Prevention: Incorporate more fiber into the diet to prevent constipation and bloating, making stool softer and easier to pass.

Anal Fissure

• Description: Small tear in the lining of the anus, causing bleeding during bowel movements and pain.

• Symptoms:

  • Pain during bowel movements.

  • A crack in the skin around the anus.

  • Blood on stool.

  • Pain to lower back and constipation.

• Treatment:

  • Stool softeners to reduce pain during bowel movements.

  • Adjust diet: increase water intake, avoid spicy foods.

  • Surgery if other treatments fail.

• Chronic Fissure:

  • If not healed within 8 weeks, considered chronic, may require serious treatment.

  • Prone to recurrence.

  • Unhealed fissures may require surgery due to discomfort.

Colorectal Cancer

• Starts as benign polyps on the inner lining of the colon or rectum; removal can prevent cancer growth.

• Located in the lower end of the digestive tract.

• Originates in the innermost layer and grows outward through the colon and rectum walls.

• Most are adenocarcinomas, starting in glands lining the organs.

• Symptoms:

  • Changes in bowel habits.

  • Rectal bleeding or blood in the stool.

  • Abdominal pain or cramping.

  • Unexplained weight loss or fatigue.

• Diagnosis & Treatment:

  • Colonoscopies and other screening tests detect polyps/early-stage cancer.

  • Surgery, chemotherapy, radiation therapy.

• Stages:

  • Describe how much cancer is in the body; determine seriousness and treatment.

  • Stage 0: earliest stage.

  • Stages range from 1 to 4.

Gastroenteritis

• Overview:

  • Known as the stomach flu.

  • Inflammation of the mucous membrane lining the stomach and intestinal tract.

• Causes:

  • Food poisoning, infection, toxins.

• Symptoms:

  • Abdominal cramping, nausea, vomiting, fever, diarrhea.

• Treatment:

  • Rest and fluids in most cases.

  • Severe cases: antibiotics, intravenous fluids, antiemetics (for vomiting), medicine to slow peristalsis.

  • Probiotics may be helpful.

Hernia

• Occurs when an internal organ pushes through a weakened area or natural opening in a body wall.

• Types and Locations:

  • Inguinal: bowel protrudes into the inguinal canal (most common, usually affects men).

  • Femoral: bowel protrudes into the femoral canal.

  • Hiatal: stomach protrudes through the diaphragm.

  • Congenital Diaphragmatic: diaphragm does not close during fetal development (birth defect).

  • Incisional: tissue protrudes at a former incision (common after abdominal surgery).

  • Umbilical: intestine protrudes through an opening near the umbilical area (congenital).

  • Ventral: any hernia located on the front wall of the abdomen.

  • Perineal: organ/tissue protrudes through an opening in the pelvic floor.

H. Pylori Infection

• Caused by Helicobacter pylori, a spiral-shaped bacterium infecting the stomach lining.

• Common infection, affecting approximately half the world's population.

• Many people are asymptomatic.

• Can cause chronic gastritis (inflammation of the stomach lining).

• Major cause of peptic ulcers (sores in the stomach or duodenum).

• Symptoms: abdominal pain, nausea, loss of appetite, bloating.

• Diagnosis: breath tests, stool tests, or endoscopy with biopsy.

• Treatment: antibiotics to kill bacteria, acid-reducing medications to heal the stomach lining.

Pancreatitis

• Inflammation of the pancreas.

• Acute Pancreatitis:

  • Sudden, short-term.

  • Symptoms: Severe abdominal pain radiating to the back, tenderness of the abdomen, nausea, vomiting.

  • Treatment: Hospital stay with IV fluids, pain medication, antibiotics.

• Chronic Pancreatitis:

  • Ongoing, long-term.

  • Causes permanent damage to the pancreas; can cause it to stop producing enzymes and insulin.

  • Symptoms: Recurring abdominal pain, weight loss, diabetes, rapid heart rate, swelling in the upper belly, fever, jaundice.

  • Causes: Excessive alcohol consumption, gallstones.

  • Treatment: Low-fat diet, surgery, vitamins.

Peptic Ulcer Disease

• Description: Open sores in the lining of the stomach or duodenum (the first part of the small intestine).

• Symptoms:

  • Dull or burning stomach pain (may be worse between meals, at night, or after eating).

  • Feeling of fullness or bloating.

  • Heartburn, nausea.

• Treatment:

  • Antibiotics to kill H. pylori.

  • Medicines to block or reduce stomach acid.

  • Antacids to counter stomach acid effects.

  • Medicines to protect the lining of the stomach and small intestine.

• Causes:

  • Helicobacter pylori (H. pylori), frequent use of NSAIDs, excess stomach acid, smoking, alcohol, stress.

• Risk Factors:

  • Infection with H. pylori, frequent use of NSAIDs, smoking, excessive alcohol, stress, family history, age, other medical conditions, unhealthy diet, irregular eating habits.

Steatorrhea

• Excessive amounts of fat in stool.

• Causes:

  • Digestive system trouble breaking down and absorbing fats.

  • Exocrine pancreatic insufficiency (pancreas unable to produce enough pancreatic enzymes).

  • Liver diseases and bile duct issues.

  • Conditions interfering with the small intestine's ability to break down fats.

• Symptoms:

  • Loose stool, foul smell, pale color, floating, abdominal pain, dehydration, oily texture, weight loss.

• Treatment:

  • Mild: limit high-fat/fiber foods, maintain a healthy diet.

  • Severe: Pancreatic enzyme replacement therapy (PERT), gluten-free diet, antibiotics.

Hemorrhoids

• Swollen and inflamed veins in the lower rectum and anus.

• Internal Hemorrhoids:

  • Location: Inside rectum (painless area).

  • Symptoms: Bright red bleeding, prolapse (may stick out), discomfort.

  • Causes: Straining, constipation, low fiber, sitting too long, pregnancy.

  • Treatment: Fiber, fluids, stool softeners, sitz baths, creams/suppositories, rubber band ligation, surgery (if severe).

• External Hemorrhoids:

  • Location: Under skin around the anus (pain-sensitive).

  • Symptoms: Pain, swelling, lump near anus, itching, sometimes bleeding.

  • Causes: Same as internal.

  • Treatment: Sitz baths, ice packs, pain relievers, topical creams, minor surgery if thrombosed (painful clot).

Gallstones (Cholelithiasis)

• Formation and hardening of bile salts and pigments due to cholecystitis (inflammation of the gallbladder).

• Symptoms: Indigestion, nausea and vomiting (emesis), fever (pyrexia).

• Treatment: Low-fat diet, analgesics (pain medications), lithotripsy (shock waves to shatter stones), cholecystectomy (surgical removal of gallbladder).

• Laparoscopic surgery: minimally invasive surgery using lasers (less painful, smaller incisions, reduces infection risk).

• Gallbladder rupture is rare but life-threatening.

• Untreated gallstones can lead to complications; treatment depends on surgery type needed.

Ulcerative Colitis

• Inflammatory bowel disease (IBD) causing ulcers and inflammation in the lining of the rectum and colon.

• Causes: No definitive causes, but factors include genes, abnormal immune reactions, microbes in the digestive tract, environment.

• Symptoms:

  • Common symptoms: Diarrhea, blood in stool or rectal bleeding, abdominal pain and cramping, mucus or pus in stool, constant urge to defecate (tenesmus).

  • Severe symptoms: Fatigue, fever, nausea or vomiting, weight loss.

• Remission and Relapse: Symptoms may have periods of remission (weeks to years), followed by relapse.

• Diagnosis:

  • Family history, physical exam, blood test, stool test, endoscopy of the large intestine.

• Treatment:

  • Medications to reduce inflammation (aminosalicylates, corticosteroids, biologics), ileoanal reservoir surgery, ileostomy.

Intussusception

• Medical emergency: one segment of intestine folds inside another (telescoping).

• Most common in children between 3 months and 3 years old.

• Symptoms: Abdominal pain, N/V, red jelly-like stool, swollen belly, lethargy.

• Diagnosis: Ultrasound, CT Scan.

• Treatment: Enema (also used for diagnosis), surgery (open or laparoscopy).

Irritable Bowel Syndrome (IBS)

• Description: Common condition affecting the gastrointestinal tract, especially the stomach and intestines.

• Symptoms:

  • Changes in stool frequency, cramping/bloating, constipation, changes in stool appearance.

• Causes: Exact cause unknown; factors include muscle contractions in the intestines, early life stress, the nervous system, bacteria/virus; symptoms triggered/worsened by food, stress, menstrual cycle.

• Risk Factors: Young age (under 50), female gender, family history of IBS, anxiety, depression, or other mental issues.

• Types of IBS:

  • IBS-C (with constipation): hard and lumpy stool.

  • IBS-D (with diarrhea): watery and loose stool.

  • IBS-M (mixed): hard, lumpy, watery, and loose stool.

• Treatment/Lifestyle Changes: Limit dairy, add fiber, limit gassy foods, avoid gluten, drink lots of water, get enough sleep, exercise daily