3. Disorders of Swallowing
- Paralysis of the Swallowing Mechanism - Dysphagia
- Damage to the 5th, 9th or 10th cranial nerve
- poliomyelitis or encephalitis - damaging the swallowing
center in the brain stem
- paralysis of the swallowing muscles - muscle dystrophy,
myasthenia gravis or botulism
- Food can go into nose & trachea
- Vomiting – operation – anesthesia - NBM
4. Disorders of Esophagus
- Achalasia is a condition in which the LES fails to relax
during swallowing - food swallowed into the esophagus
then fails to pass from the esophagus into the stomach
- damage in the neural network of the myenteric plexus
in the lower 2/3rd of the esophagus – no receptive
relaxation
- Severe prolonged achalasia – food remain for many hours
– enlarged, infected esophagus due to stasis -
Megaesophagus
- Ulceration – pain – rupture – death
- Rx – surgical, antispasmodic drug
6. Disorders of Esophagus
- LES incompetence, which permits reflux of acid
gastric contents into the esophagus
(gastroesophageal reflux disease).
- This common condition causes heartburn and
esophagitis and can lead to ulceration and stricture
of the esophagus due to scarring.
- The condition can be treated by inhibition of acid
secretion with H2 receptor blockers or omeprazole
- Surgical treatment
7. Disorders of the Stomach
- Gastritis—Inflammation of the Gastric Mucosa
- chronic bacterial infection of the gastric mucosa
- alcohol or aspirin
- Long standing – gastric atrophy - autoimmunity against
the gastric mucosa – achlorhydria – pernicious anemia
- Peptic Ulcer - an excoriated area of stomach or intestinal
mucosa caused principally by the digestive action of
gastric juice
9. Peptic ulcer
- imbalance between,
- the rate of secretion of gastric juice
- the degree of protection afforded by the
gastroduodenal mucosal barrier and the
neutralization of the gastric acid by duodenal juices
- (1) excess secretion of acid and pepsin by the gastric
mucosa
- (2) diminished ability of the gastroduodenal mucosal
barrier to protect against the digestive properties
10. Peptic ulcer
- chronic infection of the terminal portions of the
gastric mucosa and initial portions of the duodenal
mucosa, infection most often caused by the bacterium
Helicobacter pylori
- Once this infection begins, it can last a lifetime unless
it is eradicated by antibacterial therapy
- the bacterium is capable of penetrating the mucosal
barrier both by virtue of its
- physical capability to burrow through the barrier
- releasing bacterial digestive enzymes that liquefy the
barrier
11. Peptic ulcer
- Psychic disturbances
- smoking, presumably because of increased nervous
stimulation of the stomach secretory glands;
- alcohol, because it tends to break down the mucosal
barrier;
- aspirin and other NSAIDs that also have a strong
propensity for breaking down barrier
12. Peptic ulcer
- Zollinger-Ellison syndrome – gastrinomas – tumors
occur in the stomach and duodenum
- The gastrin causes prolonged hypersecretion of
acid, and severe ulcers are produced
- Rx – antibiotic, ranitidine, omeprazole, misoprostol,
antacids
- Gastrectomy, vagotomy – complicated bleeding ulcers
- Surgical removal of gastrinoma
13. Gastrectomy
- Severe multiple ulcer, carcinoma, obesity surgery
- Pernicious anemia
- Iron deficiency anemia
- Dumping syndrome
- Weakness, sweating, dizziness after meals
- Hypoglycemia
- Hypovolemia
- Hypotension
14.
15. Gastric Function Tests
- Fractional test meal
- Overnight fasting – RT insertion – fasting sample (free
acidity) – starch meal (total acidity)
- Sample also tested for blood, mucus, bile
- Histamine test
- Fasting – 0.5 mg Histamine S.C. – 200 ml gastric juice
in 1 hr – 180 ml HCL
- Augmented Histamine test
- Number of parietal cells – more in duodenal ulcer –
less in gastric ulcer
16. Gastric Function Tests
- Pentagastrin test
- Fasting – BAO – 10 mEq/hr
- Synthetic gastrin S.C. – MAO – 25,27 mEq/hr
- MAO 50 mEq/hr in duodenal ulcer
- MAO normal in gastric ulcer, carcinoma
- Insulin test
- Insulin IV infusion – hypoglycemia – vagal stimulation –
gastric secretion
- Check for vagotomy
- X-ray Abdomen standing – Gas under right diaphragm
17.
18. Gastric Function Tests
- Barium meal
- Swallowing a suspension of radiopaque barium
sulphate
- Gastric ulcer – ulcer crater
- duodenal ulcer – no crater,
- gastric carcinoma – hour glass
- IF estimation
- Endoscopy & Biopsy
19.
20.
21. Disorders of the Small Intestine
- Pancreatic Failure
- (1) in pancreatitis,
- (2) when the pancreatic duct is blocked by a gallstone
at the papilla of Vater,
- (3) after the head of the pancreas has been removed
because of malignancy
- 60 per cent of the fat entering the small intestine
may be unabsorbed, as well as one half of the
proteins and carbohydrates
22. Pancreatitis
- Acute pancreatitis or chronic pancreatitis
- The most common cause of pancreatitis is drinking
excess alcohol,
- the second most common cause is blockage of the
papilla of Vater by a gallstone
- Self digestion – vicious cycle – trypsin inhibitor
overcomed
23. Malabsorption
- Sprue – surgical removal
- Nontropical Sprue - idiopathic sprue, celiac disease
- gluten enteropathy, results from the toxic effects of
gluten present in certain types of grains - wheat and rye
- gluten has a direct destructive effect on intestinal
enterocytes
- Destruction of microvilli first – then villi – reduction of
surface area
- Rx - Removal of wheat and rye flour from the diet
24. Tropical Sprue
- occurs in the tropics and can often be treated with
antibacterial agents
- In the early stages of sprue, intestinal absorption of
fat is more impaired than absorption of other
digestive products.
- The fat that appears in the stools is almost entirely in
the form of salts of fatty acids rather than undigested
fat - steatorrhea
- The problem is one of absorption, not of digestion
25. Tropical Sprue
- very severe cases of sprue - impaired absorption of
proteins, carbohydrates, calcium, vitamin K, folic acid,
and vitamin B12
- (1) severe nutritional deficiency, often developing
wasting of the body;
- (2) osteomalacia (demineralization of the bones
because of lack of calcium);
- (3) inadequate blood coagulation caused by lack of
vitamin K;
- (4) macrocytic anemia of the pernicious anemia
type, owing to diminished vitamin B12 and folic acid
absorption
26. Paralytic ileus
- Adynamic Ileus
- Direct inhibition of smooth muscles during OT
- Peritoneum irritation
- Intestinal motility ↓
- Retention – distension – gas & fluid
- Intestinal colic
- Rx: 6 – 8 hrs rest
27. Disorders of the Large Intestine
- Constipation - slow movement of feces through the large
intestine
- dry, hard feces in the descending colon that accumulate
because of over absorption of fluid
- Any pathology of the intestines that obstructs movement
of intestinal contents, such as tumors, adhesions that
constrict the intestines, or ulcers, can cause constipation
- irregular bowel habits that have developed through a
lifetime of inhibition of the normal defecation reflexes
28. Constipation
- one does not allow defecation to occur when the
defecation reflexes are excited
- if one overuses laxatives to take the place of natural
bowel function,
- the reflexes themselves become progressively less strong
over months or years, and the colon becomes atonic
- person should establishes regular bowel habits early in
life, usually defecating in the morning after breakfast
when the gastrocolic and duodenocolic reflexes cause
mass movements in the large intestine
29. Megacolon
- severe constipation - bowel movements occur only once a
week
- allows tremendous quantities of fecal matter to
accumulate in the colon, causing the colon sometimes to
distend to a diameter of 3 to 4 inches - Hirschsprung’s
disease
- lack of or deficiency of ganglion cells in the myenteric
plexus in a segment of the sigmoid colon - neither
defecation reflexes nor strong peristaltic motility can
occur
- The sigmoid itself becomes small and spastic while
feces accumulate proximal to this area, causing megacolon
in the ascending, transverse and descending colons
30. Diarrhea
- rapid movement of fecal matter through the large
intestine
- Enteritis - inflammation usually caused either by a
virus or by bacteria in the intestinal tract.
- Infectious diarrhea - the infection is most extensive in
the large intestine and the distal end of the ileum
- the mucosa becomes extensively irritated, and its
rate of secretion becomes greatly enhanced - motility
of the intestinal wall usually increases manyfold
31. Diarrhea
- Psychogenic Diarrhea - periods of nervous tension
- Ulcerative Colitis
- allergic or immune destructive effect
- strong hereditary tendency
- extensive areas of the walls of the large intestine
become inflamed and ulcerated
32. Diarrhea
- The motility of the ulcerated colon is often so great that
mass movements occur much of the day rather than for
the usual 10 to 30 minutes
- the colon’s secretions are greatly enhanced
- the patient has repeated diarrheal bowel movements
- Rx – ileostomy - to allow the small intestinal contents to
drain to the exterior rather than to pass through the colon
for healing
- ulcers sometimes fail to heal - surgical removal of the
entire colon
33. Paralysis of Defecation
- defecation is normally initiated by accumulating feces
in the rectum, which causes a spinal cord–mediated
defecation reflex
- When the spinal cord is injured somewhere between
the conus medullaris and the brain, the voluntary
portion of the defecation act is blocked while the basic
cord reflex for defecation is still intact
- a small enema to excite action of this cord reflex,
usually given in the morning shortly after a meal, can
often cause adequate defecation
34. Dietary fibers
- Cellulose, lignin, pectin
- Prevention & Rx of constipation
- Prevent postprandial hyperglycemia – useful in
Diabetics
- ↓ blood cholesterol – bind with BS
- ↓ in carcinoma incidence
35. Vomiting
- Vomiting is the means by which the upper GIT rids
itself of its contents when almost any part of the upper
tract becomes excessively irritated, over distended,
or even over excitable
- Distention or irritation of the duodenum provides an
especially strong stimulus for vomiting
- The sensory signals that initiate vomiting originate
mainly from the pharynx, esophagus, stomach and
upper portions of the small intestines → vagal and
sympathetic afferent nerve fibers → vomiting center
36. Vomiting
- “vomiting center” – motor - 5th, 7th, 9th, 10th, and 12th
cranial nerves to the upper GIT
- vagal and sympathetic nerves to the lower tract and
through spinal nerves to the diaphragm and abdominal
muscles
- antiperistalsis begins to occur often many minutes before
vomiting appears
- At the onset of vomiting, strong intrinsic contractions
occur in both the duodenum and the stomach, along with
partial relaxation of LES, thus allowing vomitus to begin
moving from the stomach into the esophagus
37. Vomiting Act
- (1) a deep breath,
- (2) raising of the hyoid bone and larynx to pull the
upper esophageal sphincter open,
- (3) closing of the glottis to prevent vomitus flow into
the lungs,
- (4) lifting of the soft palate to close the posterior
nares
- strong downward contraction of the diaphragm
along with simultaneous contraction of all the
abdominal wall muscles
38. Vomiting Act
- squeezing the stomach between the diaphragm and
the abdominal muscles, building the intragastric
pressure to a high level
- LES relaxes completely, allowing expulsion of the
gastric contents upward through the esophagus
- small area located bilaterally on the floor of the 4th
ventricle called the chemoreceptor trigger zone
(CTZ) for vomiting
- apomorphine, morphine and some digitalis derivatives
39. Vomiting Act
- Destruction of CTZ blocks drug induced vomiting
but does not block vomiting resulting from irritative
stimuli in the GIT
- Motion sickness - stimulates receptors in the
vestibular labyrinth of the inner ear - brain stem
vestibular nuclei – cerebellum - CTZ – vomiting
- Nausea –
- (1) irritative impulses coming from the GIT,
- (2) impulses that originate in the lower brain
associated with motion sickness
41. GIT Obstruction
- (1) cancer,
- (2) fibrotic constriction resulting from ulceration or
from peritoneal adhesions,
- (3) spasm of a segment of the gut,
- (4) paralysis of a segment of the gut
- Pyloric obstruction – peptic ulcer – vomiting –
alkalosis
- Obstruction beyond the stomach – vomiting – water,
electrolytes - dehydration
42. GIT Obstruction
- obstruction is near the distal end of the large
intestine - intense feeling of constipation
- Initially no vomiting – later severe vomiting
- Prolonged obstruction of the large intestine can finally
causes rupture of the intestine itself or dehydration
- circulatory shock resulting from the severe
vomiting
44. FLATUS
- (1) swallowed air,
- (2) gases formed in the gut as a result of bacterial action,
- (3) gases that diffuse from the blood into the GIT
- Most gases in the stomach are mixtures of nitrogen and
oxygen derived from swallowed air - gases are expelled by
belching
- In the large intestine, most of the gases are derived from
bacterial action, including especially carbon dioxide,
methane and hydrogen – explosion during OT
- beans, cabbage, onion, cauliflower, corn, vinegar
45. Lactose intolerance
- The low lactase levels are associated with intolerance to
milk
- diarrhea, bloating and flatulence after ingestion of milk
- The diarrhea is due to the increased number of
osmotically active oligosaccharide molecules that
remain in the intestinal lumen, causing the volume of the
intestinal contents to increase
- The bloating and flatulence are due to the production of
gas (CO2 and H2) from disaccharide residues in the lower
small intestine and colon by bacteria