The digestive tract is also known as the Alimentary Canal or Gastrointestinal Tract (GI) – it consists of several organs responsible for the digestion and absorption of food.

FOOD JOURNEY THROUGH THE DIGESTIVE SYSTEM

FOOD —>—> MOUTH ( ingestion)  —->—> teeth, tongue, salivary glands ( chewing , secretion and lubricating of food) —>—->PHARYNX —>—> ESOPHAGUS —>—> STOMACH —>—> SMALL INTESTINE —>—>duodenum, jejunum, and ileum —>—> LIVER —>–> GALLBLADDER —>—> PANCREAS —>—> LARGE INTESTINES —>—> cecum, the ascending (right) colon, the transverse (across) colon, the descending (left) colon, and the sigmoid colon to the rectum ( excretion or defecation of waste materials)––>—> ANUS

 

MAIN ORGANS OF THE DIGESTIVE SYSTEM:

1. Mouth
2. Pharynx
3. Esophagus
4. Stomach
5. Small Intestines
6. Large Intestines
7. Anus

ACCESSORY ORGANS OF THE DIGESTIVE SYSTEM:

1. Tongue
2. Teeth
3. Salivary Glands
4. Liver
5. Gallbladder
6. Pancreas

 

PROCESS OF DIGESTION:

A.  Mouth or Oral Cavity  :The process of the digestion starts in the mouth with ingestion, where food is ingested. The mouth is consist of several accessory organs that aids in the digestion of food, namely: the tongue, teeth and the salivary glands.            

• Teeth. The teeth are designed to chew, grinding food into smaller particles.
• Tongue. The tongue is a muscular organ covered with mucosa. The upper surface of the tongue has a rough texture because of the presence of the tiny bumps called papillae. Covering the surface of the tongue are the  which allow you to determine the taste of your food (sweet, sour, bitter and salty). The tongue plays an important role in chewing and swallowing, and also in speech. The many nerves found in the tongue helps in transmitting taste signals to the brain.
• Salivary Glands. The salivary glands produce saliva, which moisten and lubricates food. It contains amylase enzyme (ptyalin) that helps in digestion.

B.  Pharynx
The pharynx, or throat, is a cone-shaped passageway of food from the mouth to the esophagus. . The pharynx also plays an important role in the respiratory system, Because the pharynx has two different functions, it contains a flap of cartilage known as the epiglottis that is located behind the tongue and in front of the larynx, It serves like a switch to direct food to the esophagus and air to the larynx. Epiglottis is in an upright position when at rest, thus allowing air to enter the larynx and lungs. It folds backward when swallowing to cover the opening of the larynx, thus food enters the esophagus instead of passing into the lungs.

C.  Esophagus
The esophagus is a muscular tube that delivers the chewed food from the pharynx to the stomach.

D.  Stomach -The stomach contains gastric enzymes and gastric juice, that help breaks food into smaller pieces, thus turning the bolus into a chyme; making it ready to pass into the small intestine. Hydrochloric acid also kills bacteria present in the food.

Parts of the stomach:

• Cardia – also called the esophagastric junction. This is the notch where the esophagus meets with the stomach. This is where the food contents of esophagus empty into the stomach.
• Fundus – is the uppermost curvature of the stomach.
• Body – largest part of the stomach.
• Pylorus -This is the part where the gastric contents empties out of the stomach and passes into the duodenum, of the small intestine.

 

E.  Small Intestine: From the stomach, food enters the duodenum, the first part of the small intestine. It then enters the jejunum, (approximately 8 feet long) and then travels to the ileum, the final segment of the small intestine (approximately 12 feet long). The small intestine terminates into the cecum. It is in the small intestine where much of the digestion and absorption of food takes place with the help of the digestive enzymes and bile secreted in the small intestine. The primary responsibility of the small intestine is the absorption of nutrients and minerals found in food. The small intestine terminates into the cecum.

Liver
The liver weighs about 3-4 pounds and is the largest internal organ and the largest gland in the body. The liver has many functions, but the main function of the liver in the process of digestion is the production of bile into the small intestine, which plays an important role in emulsifying fats.

Gallbladder
The gallbladder stores and concentrates bile and then contracts to release it into the duodenum (small intestine) to aid in the absorption and digestion of fats.

Pancreas
The pancreas is a gland that secretes pancreatic juice that contains digestive enzymes that helps in digesting and breaking down fats, proteins and carbohydrates. The pancreas also secretes insulin into the bloodstream which is produced by the Islets of Langerhans. Insulin plays an important role in the metabolism of carbohydrates.

F.  Large Intestine
The large intestine or colon is a long, thick tube (approximately 5 feet long). The large intestine is made up of the cecum (where the appendix is attached), the ascending (right) colon, the transverse (across) colon, the descending (left) colon, and the sigmoid colon, which connects to the rectum.  The large intestine absorbs water and eliminates waste materials from the body.

•  Ileocecal Valve – prevents contents of the large intestine from entering the ileum (lower   part of small intestine).

G.  Rectum
The rectum intestinum (Latin for “straight intestine”) is an 8-inch chamber which is a continuation of the sigmoid colon, and connects to the anus. It holds the stool in place until it is ready to be evacuated.

H.  Anus
The anus is the end part of the digestive tract where solid or liquid waste and gas are excreted. Excretion of waste is a process known as defecation.

CONDITIONS OF THE DIGESTIVE SYSTEM:

APPENDICITIS : Appendicitis is an inflammation of the appendix, a small tube like structure that is attached to the cecum of the large intestine. The function of the appendix is unknown. We can live normally without it.

If left untreated, an inflamed appendix can rupture or perforate and infection can spread throughout the abdominal cavity thus leading to a more serious inflammation called peritonitis and sepsis.

Symptoms of appendicitis include:

• It starts with a dull pain that progresses to sharp pain around the periumbilical part and the pain is not confined to one spot.
• As the inflammation progresses, the pain will be localized to one spot called McBurney’s point,
• A rebound tenderness will be noted when you apply pressure to the right lower quadrant.
• Abdominal rigidity
• Loss of appetite
• Elevated WBC count
• Nausea and vomiting
• Low grade fever

 

CHOLECYSTITIS  :Is an inflammation of the gallbladder, a small organ on the right side of your abdomen, just beneath your liver, which stores fluid called bile that helps in the absorption and digestion of fats. The most common cause of cholecystitis is due to a gallstone that blocks the cystic duct,

Symptom of cholecystitis:

• Right upper quadrant or epigastric pain that radiates to the scapula or around to your back or right shoulder blade.
• Murphy’s sign
• Nausea or vomiting.
• Jaundice – yellow discoloration of skin. Due to biliary obstruction, an excess amount of bilirubin is found in the blood.
• Pruritus –  itchy.
• Rebound tenderness in the right upper quadrant.
• Belching or burping.
• Fever – elevated temperature.
• Severe pain after eating fatty meals.

 

CIRRHOSIS :It is caused by chronic progressive disease of the liver, resulting in the formation of scar tissue. The scar tissue causes the liver to function inadequately and can be life threatening.Hepatitis and chronic alcohol abuse are the most common condition that causes the scarring of the liver.

Signs and symptoms when liver damage is severe may include:

• Fatigue
• Bruising easily
• Pruritus (Itchy skin)
• Jaundice– Yellow discoloration of the skin and eyes caused by excess bilirubin in the blood. This occur because the liver is unable metabolize bilirubin.
• Ascites – Fluid accumulation in the peritoneal cavity
• Loss of appetite and weight loss
• Nausea
• Vomiting (presence of blood in vomitus)
• Decreased in urinary output
• Swelling in your legs -due to fluid retention
• Altered Level of consciousness– (ALOC) and impaired thinking – present during the end stage of cirrhosis.

 

CONSTIPATION : Occurs when a bowel movement is less than 3 times in a week. Constipation is described as hard stools or difficulty, that it will cause you to strain in passing stools. Sometimes, the patient is unable to have a bowel movement even after straining or pushing

 

CROHN’S DISEASE :Is an inflammatory bowel disease (IBD). It is a chronic inflammatory condition that can occur on any part of your digestive tract, but the most commonly affected area is the ileum (the lower segment of the small intestine) The inflammation can lead to scarring, narrowing of the ileum, fistulas, ulcerations and abscesses, thus causing abdominal pain.

Symptoms:

• Fever
• Diarrhea with blood, mucus and pus
• Abdominal distention
• Cramp like and colicky pains every after meal.
• Nausea and Vomiting
• Weight loss – Due to poor appetite and inadequate intake and inadequate absorption (malabsorption) of nutrients by the intestine caused by the inflammation
• Dehydration and Electrolyte imbalance due to severe diarrhea and vomiting.

 

DIARRHEA :Is defined as having a loose, watery stool more than three times in a day.  The causes of diarrhea include bacteria, viruses or parasites, certain medicines, food intolerances (like lactic intolerance) and diseases that affect the Digestive tract.  But in most cases, the cause of diarrhea is unknown.

 

DIVERTICULOSIS :Is a condition that develops when pouches (diverticula) or herniation form in the wall of the large intestine. They can occur in any part of the colon but most commonly affect the sigmoid colon (the S shaped part of the large intestines). What exactly causes the sacs, or pouches of diverticulosis to form are still unknown. Some doctors say that a low fiber diet is most likely to be a precipitating factor. Low fiber diet can result in constipation and hard stools causing people to strain when passing stools thus leading to increase in pressure in the intestines and that may cause these pouches to form.

 

DIVERTICULITIS :Occurs when the sac or pouches (diverticula) become inflamed or infected.It happens when small pieces of stool (feces) get trapped in the pouches (diverticula) thus allowing the bacteria to grow in the pouches causing the inflammation or infection.

Symptoms include:

• Left Lower Quadrant Pain, that is sometimes worse when you move, cough, strain or lift an object. This is the most common symptom.
• Cramp like pain
• Fever and chills.
• Blood in stools
• Bloating and gas.
• Diarrhea or constipation.
• Nausea and vomiting.
• Loss of appetite

 

DUMPING SYNDROME : It is the rapid emptying of the stomach contents into the small intestines, thus the jejunum (lower segment of small intestine), fills too quickly

Symptoms occur 30 minutes to 1 hour after eating:

• Nausea and vomiting
• Abdominal fullness or bloating
• Abdominal cramping
• Diarrhea
• Dizziness
• Fatigue
• Sweating

Causes:

• Gastric Resection
• Gastric bypass surgery
• Gastrectomy

 

GALLSTONES : Also referred as cholelithiasis – Are hardened deposits made from cholesterol, bile pigments and calcium salts that can form in your gallbladder. Most gallstones are small and do not cause problems and symptoms. But if they are big and obstruct the biliary tract such as the cystic duct, common bile duct, and pancreatic duct, they can cause serious problems and require medical treatment.

Symptoms include:

• Pain on the Right Upper Quadrant of your abdomen
• Sudden and severe pain in your abdomen or chest
• Right Upper Back pain or  Pain between your shoulder blades
• Fever and chills.
• Jaundice – your skin or the whites of your eyes may turn yellow.

 

GASTRITIS : Common condition in which the lining of the stomach or gastric mucosa becomes inflamed and irritated.

A). Acute Gastritis – sudden inflammation or swelling in the lining of the stomach that causes severe pain.

Causes:

• Overuse of medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin and corticosteroids.
• Bile reflux
• Excessive alcohol consumption
• Ingestion of food that are highly seasoned and are irritating to the lining of the gastric mucosa

B). Chronic Gastritis – involves swelling or inflammation of the stomach lining that occurs slowly over time.

Causes:

• Long-term use of certain medications (aspirin and ibuprofen)
• Excessive alcohol consumption
• Smoking
• Bacteria that cause stomach ulcers (Helicobacter pylori)
• Bile reflux
• Persistent stress

 

GASTRO ESOPHAGEAL REFLUX (GER) : Also known as acid reflux or acid regurgitation – Is a condition in which the stomach contents backflow into the esophagus,thus causing heartburn and other symptoms                                                                                                                                     

Cause:

• The lower esophageal sphincter, or LES, the ring like muscle that acts as a valve between the esophagus and stomach, relaxes or becomes too weak to close, causing the stomach contents to backflow to the esophagus.

Preventive measures:

• Avoiding foods and beverages that contribute to heartburn, such as carbonated beverages, chocolate, coffee, tea, greasy or spicy foods, and alcoholic beverages
• Eat a low – fat, high fiber diet
• Avoid overeating
• Avoid eating and drinking 2 hours before bedtime
• Avoid tobacco and cigarette smoking
• Losing weight if overweight

 

GASTRO ESOPHAGEAL REFLUX DISEASE (GERD) : It is a chronic form of GER.

Factors that can contribute to GERD include:

• Hiatal hernias may also cause GERD
• Pregnancy
• Certain medications, such as aspirin, blood pressure medications, antihistamines, pain killers, , and antidepressants
• Smoking
• Eating heavy meals or lying down right after meal
• Overweight or Obesity
• Eating before bedtime

Treatments:

1). Lifestyle Changes

• Avoiding foods and beverages that contribute to heartburn, such as carbonated beverages, chocolate, coffee, tea, greasy or spicy foods, and alcoholic beverages
• Eat a low – fat, high fiber diet
• Avoid overeating
• Avoid eating 2 hours before bedtime
• Avoid tobacco and cigarette smoking
• Losing weight if overweight
• Avoiding tight clothing which can constrict the stomach area and worsen reflux
• Staying upright 1 hour or more after meals

2). Medications
3). Surgery

 

HEMORRHOIDS : Also referred to as piles. They are swollen or dilated veins located around the anal canal that may result from straining during bowel movement or during pregnancy.

Types of hemorrhoids:

• Internal hemorrhoids develop above the anal sphincter (inside the rectum) and cannot be seen during an assessment of the perianal area. They don’t hurt much.
• External hemorrhoids develop below the anal sphincter, lie around the anus and are very painful. They easily get noted during an assessment of perianal area.
• Prolapsed hemorrhoids are internal hemorrhoids that are enlarged protrude out of the rectum.

Treatment and preventive measures:

• Use stool softener as prescribed
• Hot sitz bath as prescribed
• Application of topical anesthetics as prescribed
• Encourage high fiber diet to avoid constipation thus preventing straining during bowel movement.
• Increase fluid intake to promote good bowel movement.
• Avoid anal intercourse.

HEPATITIS : It is the inflammation of the liver caused by a virus or bacteria and can also be caused by alcohol, some hepatotoxins and other infections. Other causes of hepatitis include Recreational drugs and some prescription medications.

Symptoms may include: An infected person becomes symptomatic after the incubation period, unless the person is asymptomatic which is common for viral hepatitis.

• Malaise and fatigue
• Anorexia and loss of appetite
• Serum bilirubin level are elevated
• Liver enzymes level are elevated
• Muscle pain
• Jaundice
• Abdominal pain
• Nausea and vomiting
• Fever
• Pruritus
• Diarrhea

Stages of Viral Hepatitis:

1). Incubation stage – no sign and symptoms (asymptomatic)

2). Preicteric Stage

• Fatigue, malaise and fever
• Nausea, vomiting, diarrhea
• Poor appetite
• Muscle pain, headache
• Right upper quadrant pain
• Blood test : Serum bilirubin and Liver enzymes level are elevated

3). Icteric Stage –

• Jaundice – (hallmark of hepatitis) is the yellowish discoloration of the skin and the white of the eye
• Pruritus – skin itching due to the presence of bile salts in the bloodstream
• Dark colored urine
• Clay colored stools

4). Posticteric stage – The convalescent stage

• Energy level back to normal
• Jaundice
• Symptoms resolve
• Serum bilirubin and liver enzyme level return to normal

Types of Viral Hepatitis:

1). Hepatitis A (HAV) infectious hepatitis is caused by the hepatitis A virus (HAV), found in the stool of a person with hepatitis A. It is spread from person to person primarily through fecal oral route. Hepatitis A virus is an acute self-limiting disease that can heal on its own.

Other route of transmission includes:

• Consumption of contaminated fruits, vegetable and raw shellfish.
• Contaminated drink i.e. water and milk
• Improperly washed contaminated eating utensils

Preventive measures:

• Hepatitis A vaccine – 2 doses given 6 months apart
• Strict hand washing before and after eating
• Wash hands before, during, and after preparing food.
• Wash hands after using the toilet.
• Blood test screening for food handlers.
• Stool and needle precautions

Incubation period: 15 – 45 days (2- 7 weeks)

Serologic Tests:

•  IgM
•  anti-HAV

2). Hepatitis B (HBV) serum hepatitis -infection caused by the hepatitis B virus (HBV). Hepatitis B is a contagious liver disease transmitted through exposure to an infected blood or body fluids. Symptoms last for a few weeks to months and then gradually improve if your body is able to fight off the infection, but it can also be a lifelong illness which is referred to as chronic hepatitis B. People with chronic hepatitis B may not have symptoms and not know they are infected, but can spread the hepatitis B virus to other people without knowing it.

High Risk individual:

• Persons having unprotected sex with an infected partner.
• Drug addicts – sharing needles during drug use.
• Persons with multiple sexual partners.
• Long term dialysis patients.

Route of transmission:

• Parenterally transmitted.
• Exposure to contaminated needles or sharps.
• Contact with infected blood or body fluids.
• Exposure to infected semen during unprotected sex.
• Exposure to infected blood products, i.e. during blood transfusion.
• Sexual Contact with an infected partner.
• Sharing personal items such as razors or toothbrushes with an infected person.
• Birth (infected mother transmits the infection to her baby during birth).

Hepatitis B viruses cannot be transmitted by:

• Shaking hands or holding hands with an infected person.
• Sharing eating utensils or drinking glasses with an infected person.
• Kissing or hugging, an infected person.
• Coughing or sneezing.
• A baby cannot get hepatitis B through breastfeeding.

Prevention:

• Strict Hand washing before and after patient care.
• Screening blood donors.
• Needle and sharp precaution.
• Hepatitis B Vaccinations:

1. Infants and children: 3 to 4 doses given over a
   6- to 18-month period depending on vaccine type.
2. Adults: 3 doses given over a 6-month period.

Incubation period: 42 to 160 days (6 – 23 weeks)

Serologic Test:

• HBsAg (hepatitis b surface antigen) if it still present after 6 months it indicates chronic infection.  

 3). Hepatitis C – non-A, non-B hepatitis or post transfusion hepatitis.  Hepatitis C infection is caused by the hepatitis C virus (HCV).

Route of transmission: (similar to HBV, primarily through blood).

• Parenterally transmitted
• Exposure to contaminated needles or sharps.
• Contact with infected blood or body fluids.
• Exposure to infected semen during unprotected sex.
• Exposure to infected blood products, i.e. during blood transfusion.
• Sexual Contact with an infected partner.
• Sharing personal items such as razors or toothbrushes with an infected person.
• Birth (infected mother transmits the infection to her baby during birth).

High Risks Individual:

• Health care personnel (have contacts with blood and body fluids of patients)
• Drug addicts – sharing needles during drug use
• Person  with multiple sexual partners
• Person with unprotected sex with an infected partner
• Long term dialysis patients
• HIV infected person

Incubation Period: 14 – 70 (2 – 10 weeks) but most common 6-9 weeks

Testing: HCV antibody

 4). Hepatitis D (HDV), delta agent hepatitis. It may cause infection only when you are already infected with hepatitis B.

Risk factors include:

1. Drug addicts – sharing needles during drug use
2. At birth (the pregnant mother can pass the virus to the baby)
3. Infected with hepatitis B virus
4. Male to male sexual intercourse
5. Receiving blood transfusions
6. Hepatitis D may intensify the symptoms of hepatitis B.

High Risk Individuals:

• Drug addicts – sharing needles during drug use
• Long term dialysis patients
• Persons having unprotected sex with an infected partner
• Patients receiving blood transfusions

Transmission: same as HBV

Incubation Period:  21 – 63 days (3- 9 weeks)

Prevention: same as HBV

Testing:

1.  HDAg ( hepatitis D antigen) early course of the disease
2.  Anti- HDVlater part of the infection

 5). Hepatitis E (HEV) enterically transmitted or epidemic non-A, non-B : Hepatitis E is a waterborne disease and comparable to hepatitis A.  Like HAV, HEV is usually a self-limiting infection. And is transmitted from person-to-person via the fecal-oral route, principally via contaminated water.

Transmission: same as HAV

Incubation period:  15 – 60 days (2- 9 weeks)

 

Hepatitis Home Education for Client and Family:

• Strict hand washing before and after eating.
• Strict hand washing before, during and after preparing food, infected person should avoid handling or preparing food for others.
• Infected person should avoid consumption of alcohol
• Strict hand washing after using the toilet
• Individual or separate personal  belongings like towels, razors, toothbrush and eating utensils
• Avoid donating blood
• Avoid needles and sharp objects
• Compliant with follow up with health care provider as scheduled
• Diet : high carbohydrates, low fat

 

PANCREATITIS : It is an acute or chronic inflammation in the pancreas.

• Acute Pancreatitis occurs suddenly as one time episode and last for days or can recurrent but was resolved.
• Chronic pancreatitis occurs over many years, a continual inflammation causing scar tissue

Pancreatitis of mild stage can be resolved without treatment, but severe type of pancreatitis can lead to a serious medical condition that needs medical intervention.

Symptoms:

• Cullen’s Sign can predict acute pancreatitis – bruising or bluish discoloration around the periumbilical area
• Turner’s Sign occurs in acute pancreatitis – bruising or bluish discoloration of the flanks.
• Nausea and vomiting
• Pain that gets worst by eating fatty meal or drinking alcohol.
• Epigastric or left upper quadrant pain that radiates to the back

Causes:

• gallstones (cholelithiasis)
• heavy alcohol use
• medications
• viral or bacterial infections
• trauma

 

PEPTIC ULCER DISEASE: It is ulceration in the lining of the stomach, esophagus or the duodenum.

Peptic ulcers include:

1). Gastric ulcers – Ulceration occurs in the wall of the stomach.
2). Esophageal ulcers – Ulceration occurs in the mucosal lining of the esophagus
3). Duodenal ulcers – Ulceration that occur on the wall of the duodenum (upper portion of your small intestine).

Symptoms:

•  Burning pain in the middle or upper stomach between meals or at night
• Bloating
• Heartburn
• Nausea or vomiting
• Burping
• Gets worst with  empty stomach
• Decreased in appetite

Causes:

• Stress
• Smoking cigarette
• Chewing tobacco
• Regular or Over use of NSAIDs
• Other medications that can also lead to ulcers osteoporosis called potassium supplements.
• Alcohol intake
• Chronic Gastritis
• Helicobacter pylori infection

 

ULCERATIVE COLITIS : It is an inflammatory condition of the large intestine (colon and rectum). The lining of the large intestine (colon) becomes inflamed and develops tiny ulcers thus causing poor absorption of nutrients. The inflammation most commonly affects the rectum and Sigmoid colon (lower colon). But can also occur in the entire colon.

A). Acute Ulcerative Colitis

b). Chronic Ulcerative Colitis

Symptoms:

• Loss of appetite
• Weight loss
• Fatigue
• Abdominal pain with cramping
• Severe Bloody Diarrhea
• Dehydration due to severe diarrhea

 

DIAGNOSTIC PROCEDURES FOR DIGESTIVE SYSTEM DISORDER:

• Colonoscopy
• Sigmoidoscopy
• Barium Swallow ( upper GI tract study)
• Barium Enema ( lower GI tract study)
• Liver Biopsy
• Endoscopy
• ERCP (Endoscopic Retrograde Cholangiopancreatography)
• Endoscopic Ultrasound (EUS)

 

*** Many types of Digestive System Disorders can be prevented by following a healthy lifestyle.