Gastrointestinal Disorders

The digestive system is uniquely constructed to perform its specialized function of turning food into the energy you need to survive and packaging the residue for waste disposal. Here is an overview of the structure and function of this complex system.

Mouth

The mouth is the beginning of the digestive tract; and, in fact, digestion starts here when taking the first bite of food. Chewing breaks the food into pieces that are more easily digested, while saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use.

Esophagus

Located in your throat near your trachea (windpipe), the esophagus receives food from your mouth when you swallow. By means of a series of muscular contractions called peristalsis, the esophagus delivers food to your stomach.

Stomach

The stomach is a hollow organ, or "container," that holds food while it is being mixed with enzymes that continue the process of breaking down food into a usable form. Cells in the lining of the stomach secrete a strong acid and powerful enzymes that are responsible for the breakdown process. When the contents of the stomach are sufficiently processed, they are released into the small intestine.

Small intestine

Made up of three segments - the duodenum, jejunum, and ileum - the small intestine is a 22-foot long muscular tube that breaks down food using enzymes released by the pancreas and bile from the liver. Peristalsis also is at work in this organ, moving food through and mixing it with digestive secretions from the pancreas and liver. The duodenum is largely responsible for the continuous breaking-down process, with the jejunum and ileum mainly responsible for absorption of nutrients into the bloodstream.

Contents of the small intestine start out semi-solid, and end in a liquid form after passing through the organ. Water, bile, enzymes, and mucous contribute to the change in consistency. Once the nutrients have been absorbed and the leftover-food residue liquid has passed through the small intestine, it then moves on to the large intestine, or colon.

Pancreas

The pancreas secretes digestive enzymes into the duodenum, the first segment of the small intestine. These enzymes break down protein, fats, and carbohydrates. The pancreas also makes insulin, secreting it directly into the bloodstream. Insulin is the chief hormone for metabolizing sugar.

Liver

The liver has multiple functions, but its main function within the digestive system is to process the nutrients absorbed from the small intestine. Bile from the liver secreted into the small intestine also plays an important role in digesting fat. In addition, the liver is the body's chemical "factory." It takes the raw materials absorbed by the intestine and makes all the various chemicals the body needs to function. The liver also detoxifies potentially harmful chemicals. It breaks down and secretes many drugs.

Gallbladder

The gallbladder stores and concentrates bile, and then releases it into the duodenum to help absorb and digest fats.

Colon (large intestine)

The colon is a 6-foot long muscular tube that connects the small intestine to the rectum. The large intestine is made up of the cecum, the ascending (right) colon, the transverse (across) colon, the descending (left) colon, and the sigmoid colon, which connects to the rectum. The appendix is a small tube attached to the cecum. The large intestine is a highly specialized organ that is responsible for processing waste so that emptying the bowels is easy and convenient.

Stool, or waste left over from the digestive process, is passed through the colon by means of peristalsis, first in a liquid state and ultimately in a solid form. As stool passes through the colon, water is removed. Stool is stored in the sigmoid (S-shaped) colon until a "mass movement" empties it into the rectum once or twice a day. It normally takes about 36 hours for stool to get through the colon. The stool itself is mostly food debris and bacteria. These bacteria perform several useful functions, such as synthesizing various vitamins, processing waste products and food particles, and protecting against harmful bacteria. When the descending colon becomes full of stool, or feces, it empties its contents into the rectum to begin the process of elimination.

Rectum

The rectum (Latin for "straight") is an 8-inch chamber that connects the colon to the anus. It is the rectum's job to receive stool from the colon, to let the person know that there is stool to be evacuated, and to hold the stool until evacuation happens. When anything (gas or stool) comes into the rectum, sensors send a message to the brain. The brain then decides if the rectal contents can be released or not. If they can, the sphincters relax and the rectum contracts, disposing its contents. If the contents cannot be disposed, the sphincter contracts and the rectum accommodates so that the sensation temporarily goes away.

Anus

The anus is the last part of the digestive tract. It is a 2-inch long canal consisting of the pelvic floor muscles and the two anal sphincters (internal and external). The lining of the upper anus is specialized to detect rectal contents. It lets you know whether the contents are liquid, gas, or solid. The anus is surrounded by sphincter muscles that are important in allowing control of stool. The pelvic floor muscle creates an angle between the rectum and the anus that stops stool from coming out when it is not supposed to. The internal sphincter is always tight, except when stool enters the rectum. It keeps us continent when we are asleep or otherwise unaware of the presence of stool. When we get an urge to go to the bathroom, we rely on our external sphincter to hold the stool until reaching a toilet, where it then relaxes to release the contents.

diseases of the oesophagus

GASTROESOPHAGEAL REFLUX DISEASE (GERD)/OESOPHAGITIS

This is a condition that produces indigestion and heartburn from the backflow of acidic gastric juices onto the lower oesophageal mucosa.

Causes

Irritating effect of acidic gastric reflux on the oesophageal mucosa
Stress
Ingestion of an irritating agent
Viral inflammation
Fungal infection
Intubation
Aging
Radiation such as for lung cancer treatment
Medication that gets stuck in oesophagus e.g. tetracycline
Chronic or reflux esophagitis is a result of recurrent gastroesophageal reflux owing to a hiatal hernia, reduced Lower Oesophageal Sphincter (LES) pressure, increased abdominal pressure and recurrent vomiting.

Symptoms

Heartburn
Regurgitation
Dysphagia
Bleeding

Nutrition implication

Indigestion
Anaemia

Aims of nutritional management

Prevent irritation of the oesophageal mucosa in the acute phase
Prevent oesophageal reflux
Decrease the irritating capacity or acidity of gastric juice

Dietary Management

In acute phase give liquid diet that is less abrasive to the oesophagus
Avoid acidic foods e.g. citrus fruits, tomato products, coffee, carbonated beverages, alcohol and spices (all of which lower LES) according to individual tolerance.
Provide low fat foods and small frequent meals
Timing of the evening meal is important. The patient should consume nothing except water for 3 hours before lying down
Avoid or quit smoking as it also triggers acid production
Elevate the head of the bed when sleeping
Avoid clothing that is tight on the abdominal area and maintain upright posture during and after eating.
Reduce weight if overweight

HIATAL HERNIA

Refers to anatomical abnormality in which part of the stomach protrudes through the diaphragm into the chest; that is an out pouching of a portion of the stomach in to the chest through the oesophageal hiatus of the diaphragm.

Usually the stomach is completely below the diaphragm (the sheet of muscle that separates the lungs and chest from the abdomen). But in some people, part of the stomach or the sphincter can slide up into the chest cavity. This is called a hiatus hernia. It's quite common, but in some people it may cause heartburn due to reflux of stomach acid.

Causes

Larger than normal oesophagi hiatus (opening in the diaphragm through oesophagus passes from the chest into the abdomen)

Symptoms

Discomfort after heavy meals
Stomach distension
Difficulty in breathing, lying down and bending

Dietary management

In acute phase provide liquid diet that is less abrasive to the oesophagus
Avoid acidic foods e.g. citrus fruits, tomato products, coffee, carbonated beverages, alcohol, spices (all of which lower LES) according to individual tolerance
Provide low fat foods and small frequent meals
Timing of the evening meal is important. The patient should consume nothing except water for 3 hours before lying down
Avoid or quit smoking as it also triggers acid production
Elevate the head of the bed when sleeping
Avoid clothing that is tight on the abdominal area and maintain upright posture during and after eating
Reduce weight if overweight

Diseases of the stomach

Peptic Ulcers

Peptic ulcer is the general term given to an eroded mucosal lesion in the central position of the gastro intestinal tract. The areas affected include the lower portion of the oesophagus, the stomach and the first part of the duodenum. A bacteria helicobacter pyroli is the biggest cause of peptic ulcers; the second leading cause is the use of non-steroidal anti inflammatory drugs (NSAIDS) that may damage the stomach lining. Eating spicy food does not cause ulcers. Gastric normally occur in adults 45-60 and duodenal occur at age 20-30.

Causes

Factors that disrupt the mucosal barrier, permitting hydrogen ions to diffuse into the mucosal tissue where they cause damage that leads eventually to cell distraction and subsequent ulceration
Enteral gastritis from Helicobacter pylori
Defect in the pyloric sphincter resulting in reflux of the duodenal content in to the antrum of the stomach where the detergent effect of bile salts reduces mucosal resistance
NSAID's (non steroid anti inflammatory drugs) e.g. aspirin, brufen, diclofenac, paracetamol, dramatically increase the risk of ulcers
Increased acid secretion
Increased gastric acid emptying rate
Reduced ability of the duodenum to handle an acid load
Stress or nervous tension which causes vasoconstriction or reduce blood supply to the gastric mucosa leaving it unprotected

Symptoms of peptic ulcers

Pain
Vomiting
Haemorrhage

Relationship of food to gastric irritation

Hydrochloric acid and pepsin breaks down food proteins-Mucus protects lining of stomach from being digested by HCL and pepsin
Ulcer develops when acid pepsin reaction overpowers mucus protection action
Food causes stomach to expand-Expansion signals release of hormone that stimulates acid secretions
Proteins stimulate and neutralize gastric acidity-Products that result from breakdown stimulate gastric secretions that are responsible for pain experienced 1 to 3hrs after a meal
Chemical irritants e.g. caffeine irritate gastric mucosa
Stimulants are found in spices, alcoholic beverages, aspirin, tobacco and some other drugs should be restricted

Nutritional implications of peptic ulcers

It could lead to:

Anaemia
Altered food and nutrient intake-reduced food intake which can result to malnutrition

Aims of nutrition management

Reducing and neutralizing stomach acid secretion
Maintaining acid resistance of gastro-intestinal epithelial tissue
Limiting patient's discomfort and reliving their pain
To provide continuous neutralization of gastric acid
To promote healing and reduce irritation of GIT
Restoring good nutrition status
To reduce mechanical, thermal and chemical irritation to the gastric mucosa

Dietary management

The patient with peptic ulcer disease should:

Eat three regular meals daily
Eat small meals to avoid stomach distension
Eat slowly
Use in moderation easily digested fats like fat of whole milk, egg yolk, cream and butter
Avoid drinking excess coffee and alcohol
Cut down on or quit smoking
Avoid using large amounts of aspirin, other NSAID's or other drugs known to damage the stomach lining
Avoid foods or drinks that cause discomfort
Eat meals in a relaxed atmosphere as possible
Take antacids one and three hours after meals and before bedtime

Bland diet

Moderate in fibre and connective tissues
Little or no condiments or spices except salt in small amounts
Avoid or eliminate highly acid foods
Foods simply prepared

Foods to avoid

Fatty and tough meat
Fried foods
Sour foods
Unripe citrus fruits like oranges and sweet lime
Garlic
Ginger strongly flavoured vegetables
Strong spices and condiments
Chillies, pickles
Strong tea and coffee
Alcoholic beverages

Foods recommended for use

Cabbage: fresh juice, fermented or raw has anti inflammatory effects
Potatoes: nutritious, anti acid, soothing and sedating
Other vegetables: carrots, peas, okra, other leafy vegetables that are tolerated (pilipili hoho)
Fruits: orange juice, apples, ripe bananas, avocadoes, pears, pawpaw, apricots, cherimoya and guava
Okra: contain mucilage capable of protecting gastric mucosa
Cereals: porridge, oatmeal, semolina, macaroni products, spaghetti, rice, chapatti and matoke
Desserts: custards, ice creams, cakes
Oils: use polyunsaturated fatty acids
Beverages: buttermilk, malted milk
Eggs: boiled, poached, scrambled
Roast beef and lamb, stewed or baked should be used in moderations because they contain purines (non protein substances that stimulate gastric mucosa)

GASTRIC DISEASES

Gastric diseases include: indigestion, acute gastritis, chronic gastritis, dumping syndrome, duodenal and gastric ulcers.

Indigestion

You get indigestion when the acid in the stomach flows back up the oesophagus (the pipe that goes from the mouth to the stomach) or when the stomach is irritated or inflamed. Most people have suffered from indigestion after a large meal at some time, and up to four in 10 adults suffer from heartburn each year. Although it's most common after meals, you can get indigestion at any time.

It refers to any discomfort in the digestive tract. Indigestion is mainly caused by gall bladder disease, chronic appendicitis, ulcer disease, stress, rapid eating, poor mastication, over indulgence and food allergies.

Symptom

Discomfort in the digestive tract

Nutritional implication

Inadequate food and nutrient intake

Dietary management

Provide a well balanced diet
Avoid rapid eating, poor mastication and over-indulgence
Take plenty of potable drinking water

ACUTE GASTRITIS

This is a temporary inflammation of the gastric mucosa, usually self-limiting caused by the indigestion of infectious or corrosive substances e.g. aspirin, food poisoning, radiation therapy, metabolic alcoholism, acute alcoholism and uraemia.

Causes

Acute gastritis is mainly caused by over eating, over use of alcohol and tobacco, chronic or excessive doses of aspirin or non-steroidal anti-inflammatory agents (NSIA), trauma, surgery, shock, jaundice, fever, renal failure, burns and radiation therapy.

Symptoms

Nausea
Vomiting
Malaise
Anorexia
Headache
Haemorrhage
Pain

Nutrition implications

Anaemia
Loss of nutrients
Increased metabolism

Aims of nutrition management

Relieve pain
Manage dietary deficiencies

Dietary management

To allow the stomach time to rest and heal, withhold food for 24 to 48hrs or longer, depending on whether there is bleeding or pain
Give fluids intravenously during this period
Add fluids as tolerated following the resting period
Increase number of feeds according to the patient's tolerance, until a full regular diet is achieved
Avoid seasoned foods

CHRONIC GASTRITIS

This condition is marked by progressive and irreversible atrophy of the gastric mucosa related to chronic inflammation. The loss of mucosal cell function may lead to achlorhydria (lack of HCl in the stomach), pernicious anaemia (look at causes of this anaemia) and malnutrition. Additional complications may include perforation, haemorrhage, and pyloric obstruction related to the scar tissue.

Crohn disease is a chronic (slowly developing, long-term) inflammation of the digestive tract. It can affect any part of the digestive tract from the mouth to the anus but usually involves the terminal part of the small intestine, the beginning of the large intestine (cecum), and the area around the anus. The inflammation causes uncomfortable and bothersome symptoms and may produce serious damage to the digestive tract. Crohn disease is sometimes called regional enteritis or ileitis. It and a similar condition called ulcerative colitis are referred to together as inflammatory bowel diseases. These illnesses are known for their unpredictable flares and remissions.

The inflammation usually starts in one or more areas of the mucosa that lines the inside of the intestines.

The disease may invade deeper tissues of the intestinal wall and spread to involve more areas of the bowel
Ulcers may form at the sites of the most intense inflammation
The ulcers may spread and become very large but are usually separated by areas of relatively healthy tissue with little or no inflammation
The mucosal lining of the intestines in Crohn disease is often described as looking like a cobblestone street, with areas of ulceration separated by narrow areas of healthy tissue

The inflammation damages the lining of the intestine so that it cannot absorb nutrients, water, and fats from the food you eat. This is called malabsorption, and it can result in malnutrition, dehydration, vitamin and mineral deficiencies, gallstones, and kidney stones.

As the inflammation invades deeper into the intestinal tissues, the intestinal wall becomes thicker, narrowing the bowel lumen (the space through which food passes). The intestinal lumen may become so narrow that it becomes obstructed, so that food cannot pass through at all. This obstruction is usually intermittent, meaning that it comes and goes, and gets better with medical treatment. Eventually, however, the obstruction can become permanent.

If the inflammation in one area spreads all the way through the intestinal wall, the inflamed area can stick to other organs and structures in the abdomen.

Crohn disease can also cause problems around the anus. These may include tiny but painful cracks in the skin known as anal fissures; tunneling sores called fistulas that cause abnormal connections between the bowel and the skin; or an abscess, a pocket of inflamed or dead tissue that is usually very painful.

Cause

Cause is unknown, but usually precedes the development of gastric lesions such as cancer or ulcer
It may be caused by an enteral infection with Helicobacter pylori
It may also be indirectly due to diseases such TB, myocardial failure and nephritis

Symptoms

Maybe vague or absent
Loss of appetite, feeling of fullness, belching, vague epigastric pain, nausea and vomiting

Nutrition implication

Altered food intake
Loss of nutrients

Aims of nutritional management

Restore nutrient loss
Maintain adequate food and nutrient intake

Dietary management

Nutrition care must follow general guidelines because the symptoms are vague
The prescription of individualised treatment based on foods and situations determined to cause discomfort is most important
Diet should be adequate in calories and soft in consistency
Encourage patient to eat at regular intervals, chew food thoroughly and avoid foods known to cause discomfort
Bland diet is recommended
Minimize drinking fluids with food; drinking lots of fluids with food tends to cause discomfort because of stomach distension
In atrophic gastritis there is loss of secretion of HCL and B12 intrinsic factor, therefore Vitamin B12 status should be assessed

Crohns disease can lead to dumping syndrome

what is DUMPING SYNDROME?

This is a complication of gastric surgeries in which the pyloric sphincter is removed, bypassed or disrupted. This causes partially digested food to rapidly enter the jejunum, it is quickly digested and creates a hyperosmolar load. Fluid from the intestinal capillaries enters the jejunum, diminishing blood volume and stimulating peristalsis, resulting into low blood pressure and diarrhoea.

Causes

Gastric surgery (post-gastrotomy, hypoglycaemia caused by: pyloroplasties, vagotomies, total gastrotomy, and gastric by-pass surgery)

Symptoms

Sweating
Weakness
Diarrhoea
Rapid pulse rate
Dizziness
Paleness
Crampy abdominal pain

Nutritional implications

Loss of nutrients
Weight loss

Aims of nutrition management

Provide adequate calories and nutrients to support tissue healing
Prevent weight loss
Correct hypoglycaemia in the short term

Dietary Management

After surgery the following should be done:

All fluids and foods by mouth should be withheld for 3 to 5 days and the patient fed by nasogastric tube
Ice chips should be held in mouth or small, infrequent sips of water should be given. Some people tolerate warm water better than ice chips or cold water
Low carbohydrates, clear liquids such as soups, or diluted unsweetened fruit juices should be given and limited to ½ to 1 cup servings, however, at least 6 cups of fluids should be consumed daily to replace losses resulting from diarrhoea. Carbonated beverages and milk are not recommended in the initial stages of the diet
The post-gastrotomy diet then begins with gradual progression to a general diet as tolerated. Bland foods should be started first, but a more important priority is offering the patient foods he/she likes and can tolerate. By the 5th to 7th day most patients can tolerate solid foods
For persons near desirable body weight about 1.5g to 2g protein should be given (35Kcal to 45Kcal/kg)
Pectin, a dietary fibre found in fruits and vegetables maybe helpful in treating dumping syndrome. Pectin delays gastric emptying, slow carbohydrate absorption and reduces glycemic response, though small dry meals are of more benefit
Vitamin and mineral supplementation maybe necessary depending on the extent of surgery and whether the symptoms of dumping syndrome persist
Generally, liquids are served between meals rather than with meals to slow the passage of the food mass. Limit simple carbohydrates
Lie down immediately after eating to help slow the transit of food to the intestines. Clients who experience reflux should not lie down after eating. Beware that lactose intolerance may develop and produce discomfort in relation to milk and milk products

INFLAMATORY BOWEL DISEASE (IBD)

This refers to inflammation of the bowel. There are two conditions under IBD namely: Crohn's disease and ulcerative colitis.

Crohn's disease

This refers to a chronic inflammatory bowel disease.

Causes

Inadequate food intake
Loss of protein in to the gut lumen
Fever
Low grade but chronic intestinal obstruction
Malabsorption or mal-digestion of fat and protein
Possibly zinc deficiency

Symptoms

Fatigue, anorexia, variable weight loss, right lower quadrant pain or cramping, diarrhoea, fever and stricture formation may precipitate bowel obstruction.

Nutrition implications

Inadequate food and nutrient intake
Malabsorption and mal-digestion
Increased nutrient needs

Aims of nutrition management

Restoration of good nutritional status
Relief of discomfort

Dietary management

During acute flare-ups bowel rest and parenteral nutrition is recommended
Later in patients who cannot tolerate whole foods elemental oral formula maybe useful
Energy and protein content of the diet should be high to promote healing and restore weight. Provide 40 - 50Kcal/Kg, and for protein 1 - 1.5g/Kg
Give a low fibber diet to minimize bowel stimulation
Give small frequent meals that are better tolerated than three large meals, this may help maximize intake
Assess status of calcium, magnesium and zinc since steatorrhea promotes their loss

Diseases of the large intestine

ULCERATIVE COLITIS

The disease is characterised by inflammation and ulceration of the large intestines that always begins in the rectum.

Cause

It is likely that intestinal allergy caused by some foods like milk maybe responsible for the disease in some cases.

Symptoms

Passage of loose stool with mucus and blood accompanied by pain and spasms
Loss of appetite
Rectal bleeding
Fever
Ulcerative lesions in the mucosa of the large intestines
Dehydration
Electrolyte imbalance
Anorexia
Malnutrition

Nutrition implications

Anaemia
Increased nutrient needs
Fluid imbalance
Food mal-digestion and nutrient malabsorption

Aims of nutrition management

To relieve pain and inflammation
To restore and maintain optimal nutritional status

Dietary management

Same as in Crohn' disease. However, no dietary interventions seem to lessen disease activity. And unlike Crohn's disease where intestinal surgery fails to cure the disorder, removal of the colon and the rectum does cure ulcerative colitis

DIVERTICULAR DISEASE

Diverticular refers to the small out pouching in the gastrointestinal tract. These pouching may occur in the oesophagus as well as in the lower intestine. It is caused by increased pressure within the intestinal lumen, which may be related to chronic constipation and long term low fibre diets. Diverticular usually occur in the weakened areas of the tissue resulting from such factors as tissue irritation, secretory or muscular malfunctioning. Diverticulitis refers to inflammation of the Diverticular.

Causes

Aging
Low fibre diets

Symptoms

Gross bleeding
Low Hb and albumin levels
Ulceration or even perforations of the lower intestine
Dysphagia
Cramping
Alternating periods of diarrhoea and constipation
Regurgitation
Bad breath and foul taste in the mouth
Low grade fever

Nutritional implications

Anaemia
Increased nutrient needs

Aims of nutrition management

To restore nutritional status
To relieve pain and enhance healing

Dietary management

In chronic cases, provide a moderately fiber restricted diet
In acute cases, provide clear liquid diet with progression to a very low-residue diet
Ensure high calories diet to cater for the increased calories needs, except in overweight cases where normal calories requirement may be provided to check on the weight
High protein is needed for repair of worn out tissues
Ensure that the diet is of low fats