digestive system and disorders

details about digestive system and diseases

1. Anatomy & Physiology OF HARISHANKAR SAHU B.PHARMA FINAL YEAR SRIP,KUMHARI BY- Digestive System

2. Organs of the Digestive System Mouth teeth Salivary glands Pharynx Esophagus Stomach Liver Gallbladder (GB) Pancreas Small intestine Large intestine Rectum Anus

3. Main Functions Digesting food Physical and chemical breakdown of large food into molecules: glucose, triglycerides, amino acids Absorbing nutrients From intestines Circulated through the body by cardiovascular system Eliminating waste Any food that cannot be digested or absorbed is expelled

4. Oral Cavity (mouth) Roof is palate Hard – bony anterior Soft – flexible posterior Hanging down from soft palate is uvula Speech production Location of gag reflex

5. Oral Cavity Cheeks are lateral walls Lips are anterior opening Entire cavity lined with mucous membrane

6. Oral Cavity Digestion begins when food enters mouth Mechanically broken up by chewing Tongue moves food within mouth Mixes with saliva Digestive enzymes Lubricates Taste buds on tongue surface Detect bitter, sweet, salty, sour flavors

7. Processes of the Mouth Mastication (chewing) of food Mixing masticated food with saliva Initiation of swallowing by the tongue Allowing for the sense of taste

8. Salivary Glands Produce saliva Prevents bacterial infection Lubrication Contains salivary amylase Breaks down starch

9. Three pairs of Salivary Glands Parotid – lateral side of face, anterior to ear, drain by parotid duct to vestibule near 2nd upper molar Submandibular – medial surface of mandible – drain near lingual frenulum drain posterior to lower molars Sublingual – in floor of mouth - drain near frenulum

10. Function Mixture of mucus and serous fluids Helps to form a food bolus Contains salivary amylase to begin starch digestion Dissolves chemicals so they can be tasted

11. Teeth The role is to masticate (chew) food Humans have two sets of teeth 1. Deciduous (baby or milk) teeth 20 teeth are fully formed by age two 2. Permanent teeth Replace deciduous teeth beginning between the ages of 6 to 12 A full set is 32 teeth, but some people do not have wisdom teeth

12. Classification of Teeth

13. Pharynx Anatomy Nasopharynx – not part of the digestive system Oropharynx – posterior to oral cavity Laryngopharynx – below the oropharynx and connected to the esophagus

14. Pharynx Function Serves as a passageway for air and food Food is propelled to the esophagus by two muscle layers Longitudinal inner layer Circular outer layer Food movement is by alternating contractions of the muscle layers (peristalsis)

15. Esophagus 10 inches long in adults Food enters from pharynx Runs from pharynx to stomach through the diaphragm Conducts food by peristalsis (slow rhythmic squeezing) Passageway for food only (respiratory system branches off after the pharynx) Joins stomach at cardiac orifice * Cardiac sphincter at cardiac orifice to prevent regurgitation (food coming back up into esophagus) Esophagus___________

16. Stomach Lies mostly in LUQ But pain can be epigastric or lower Just inferior to (below) diaphragm Anterior (in front of) spleen and pancreas Tucked under left lower margin of liver Anchored at both ends but mobile in between Capacity: 1.5 L food; max capacity 4L (1 gallon) 16 epigastrium junction with esophagus funnel shaped contains pyloric sphincter dome

17. 17

18. Stomach J-shaped; widest part of alimentary canal Temporary storage and mixing – 4 hours Into “ chyme ” Starts food breakdown Pepsin (protein-digesting enzyme needing acid environment) HCl (hydrochloric acid) helps kill bacteria Stomach tolerates high acid content but esophagus doesn’t – why it hurts so much when stomach contents refluxes into esophagus (heartburn; GERD) Most nutrients wait until get to small intestine to be absorbed; exceptions are: Water, electrolytes, some drugs like aspirin and alcohol (absorbed through stomach) 18

19. Stomach Functions Acts as a storage tank for food Site of food breakdown Chemical breakdown of protein begins Delivers chyme (processed food) to the small intestine It secretes intrinsic factor which is necessary for the absorption of vit.B12

20. Small intestine Longest part of alimentary canal (2.7-5 m) Site of greatest amount of digestion and absorption Small intestine has 3 subdivisions Duodenum – 5% of length Jejunum – almost 40% Ileum – almost 60% Modifications Circular folds or plicae circulares , villi , lacteal, microvilli Cells of mucosa Absorptive, goblet,granular , endocrine

21. Small intestine designed for absorption Huge surface area because of great length Structural modifications also increase absorptive area Circular folds ( plicae circulares ) Villi (fingerlike projections) 1 mm high – simple columnar epithelium: velvety Microvilli * Absorptivie cell with microvilli to increase surface area & many mitochondria: nutrient uptake is energy-demanding

22. Villi of the Small Intestine Fingerlike structures formed by the mucosa Give the small intestine more surface area

23. Microvilli of the Small Intestine Small projections of the plasma membrane Found on absorptive cells Figure 14.7c

24. Structures Involved in Absorption of Nutrients Absorptive cells Blood capillaries Lacteals (specialized lymphatic capillaries)

25. Digestion in the Small Intestine Pancreatic enzymes play the major digestive function Help complete digestion of starch (pancreatic amylase) Carry out about half of all protein digestion ( trypsin , etc .) Responsible for fat digestion (lipase) Digest nucleic acids (nucleases) Alkaline content neutralizes acidic chyme

26. Absorption in the Small Intestine Water is absorbed along the length of the small intestine End products of digestion Most substances are absorbed by active transport through cell membranes Lipids are absorbed by diffusion Substances are transported to the liver by the hepatic portal vein or lymph

27. Large Intestine Larger in diameter, but shorter than the small intestine Frames the internal abdomen Digested residue reaches it Main function: to absorb water and electrolytes

28. Structures of the Large Intestine Cecum – saclike first part of the large intestine Appendix Accumulation of lymphatic tissue that sometimes becomes inflamed (appendicitis) Hangs from the cecum Colon Ascending Transverse Descending S-shaped sigmoidal Rectum = Rectum is area for storage of feces Leads to the anus, the external opening of the alimentary canal Defecation

29. Functions of the Large Intestine Absorption of water Eliminates indigestible food from the body as feces Does not participate in digestion of food Goblet cells produce mucus to act as a lubricant

30. Food Breakdown and Absorption in the Large Intestine No digestive enzymes are produced Resident bacteria digest remaining nutrients Produce some vitamin K and B Release gases Water and vitamins K and B are absorbed Remaining materials are eliminated via feces

31. Accessory Organs of the Digestive System Gallbladder Liver Pancreas

32. The Liver Largest gland in the body (about 3 pounds) Over 500 functions Inferior to diaphragm in RUQ and epigastric area protected by ribs R and L lobes Plus 2 smaller lobes Falciform ligament Mesentery binding liver to anterior abdominal wall 2 surfaces Diaphragmatic Visceral Covered by peritoneum Except “bare area” fused to diaphragm 32

33. 33

34. Functions of the Liver Bile production Salts emulsify fats, contain pigments as bilirubin Storage Glycogen, fat, vitamins, copper and iron Nutrient interconversion Detoxification Hepatocytes remove ammonia and convert to urea Phagocytosis Kupffer cells phagocytize worn-out and dying red and white blood cells, some bacteria Synthesis Albumins, fibrinogen, globulins, heparin, clotting factors

35. Role of the Liver in Metabolism Several roles in digestion Detoxifies drugs and alcohol Degrades hormones Produce cholesterol, blood proteins (albumin and clotting proteins) Plays a central role in metabolism

36. Gallbladder Bile is produced in the liver Bile is stored in the gallbladder Bile is excreted into the duodenum when needed (fatty meal) Bile helps dissolve fat and cholesterol If bile salts crystallize, gall stones are formed Intermittent pain: ball valve effect causing intermittent obstruction Or infection and a lot of pain, fever, vomiting, etc. 36 *

37. Figure:- The Gallbladder

38. Pancreas Produces a wide spectrum of digestive enzymes that break down all categories of food Enzymes are secreted into the duodenum Alkaline fluid introduced with enzymes neutralizes acidic chyme Endocrine products of pancreas Insulin Glucagons

39. Pancreas Anatomy Endocrine Pancreatic islets produce insulin and glucagon Exocrine Acini produce digestive enzymes Regions : Head, body, tail Secretions Pancreatic juice (exocrine) Trypsin Chymotrypsin Carboxypeptidase Pancreatic amylase Pancreatic lipases Enzymes that reduce DNA and ribonucleic acid

40. Processes of the Digestive System Ingestion – getting food into the mouth Propulsion – moving foods from one region of the digestive system to another Peristalsis – alternating waves of contraction Segmentation – moving materials back and forth to aid in mixing

41. Processes of the Digestive System Mechanical digestion Mixing of food in the mouth by the tongue Churning of food in the stomach Segmentation in the small intestine Chemical Digestion Enzymes break down food molecules into their building blocks Each major food group uses different enzymes Carbohydrates are broken to simple sugars Proteins are broken to amino acids Fats are broken to fatty acids and alcohols

42. Processes of the Digestive System Absorption End products of digestion are absorbed in the blood or lymph Food must enter mucosal cells and then into blood or lymph capillaries Defecation Elimination of indigestible substances as feces

43. Processes of the Digestive System

44. DISORDERS OF THE GASTROINTESTINAL SYSTEM

45. Disorders of the upper GI system Disorders affecting Ingestion ANOREXIA: lack of appetite, could be from emotional or physical factors lab tests may be done to assess nutritional status Medical treatment :supplements may be ordered, TPN or enteral feedings Nursing Interventions: oral hygiene, clean room, determine cause of nausea and treat, include family and friends(socialization), respect likes and dislikes, education

46. STOMATITIS Inflammation of the oral mucosa (mouth) Causes: trauma, organisms, irritants, nutritional deficiency, diseases, chemotherapy S/S : swelling, pain, ulcerations, excessive salivation, halitosis, sore mouth Treatment: pain relief, removal of causative factor, oral hygiene, medications, soft bland diet

47. GINGIVITIS Inflammation of the gums Causes : poor oral hygiene, poorly fitting dentures, nutritional deficiency S/S: red , swollen, bleeding gums, painful Treatmen t: dental hygiene, prevention of complications

48. HERPES SIMPLEX TYPE 1 Infection affecting the lips and mucous membranes of the mouth Causes : Herpes simplex virus S/S : Vesicles on the mouth, nose or lips, malaise, edema of surrounding area Treatment : Antiviral medication(Zovirax), analgesics, symptomatic relief Nsg Interventions: Administer meds, keep lesions dry, provide symptomatic relief

49. LEUKOPLAKIA Abnormal thickening and whitening of the epithelium of the mucous membranes of the cheeks and tongue Causes: Chronic irritation S/S: Thickened white or reddish lesions on the mucous membrane, lesions can not be rubbed off Treatment : May be surgically removed or treated with chemotherapy, meticulous oral hygiene Interventions : Assess mouth frequently, assist with oral hygiene, discuss removal of sources of irritation

50. ORAL CANCER Malignant lesions may develop on the lips, oral cavity, tongue and pharynx. Generally squamous cell carcinomas Causes : high alcohol consumption, tobacco use, external irritants S/S : Leukoplakia , swelling, edema, numbness, pain Diagnosis: biopsy Treatment: Surgery Radiation or chemotherapy depends on the size and location and the lesion Interventions: consult MD for special mouth care, monitor respiratory status, keep HOB elevated, administer pain med, assess ability to swallow and talk, assess for infection at incision site, education.

51. ESOPHAGITIS Inflammation or irritation of the esophagus Causes : Reflux of stomach contents, irritants, fungal infections, trauma, malignancy, intubation S/S : heartburn, pain, dysphagia Treatment : treat underlying cause Interventions : soft bland diet, administer meds, elevate HOB, observe for complications

52. NAUSEA AND VOMITING Nausea: unpleasant sensation usually preceding vomiting, may have abdominal pain, pallor, sweating, clammy skin Causes: irritating food, infection, radiation, drugs, hormonal changes, surgery, inner ear disorders, distention of the GI tract Vomiting: forceful expulsions of stomach contents through the mouth. Occurs when vomiting reflex in the brain is stimulated. Projectile vomiting- is forceful ejection of stomach contents. Regurgitation- gentle ejection of stomach contents without nausea or retching

53. Complications and Treatment May lead to dehydration, metabolic alkalosis, aspiration Treatment: Antiemetics ( Phenergan , Dramamine, Scopolamine patch Reglan ), IV fluids, NG tube, TPN Nursing care: through assessment, keep patient comfortable, offer liquids, position on side, suction setup in the room

54. GASTRITIS Inflammation of the lining of the stomach ACUTE: excessive intake of food or alcohol. Food poisoning, chemical irritation CHRONIC: repeated episodes of acute, H Pylori

55. Signs/Symptoms and Complications Nausea, vomiting, feeling of fullness, pain in stomach, indigestion. With chronic may have only mild indigestion changes in stomach lining with decrease in acid and intrinsic factor ( high risk for pernicious anemia)

56. Treatment Treat symptoms, and fluid replacement Medications: antacids, H2 receptor blockers, B 12 injections, corticosteroids analgesics, antibiotics if H Pylori bland diet, frequent meals Eliminate the cause surgical intervention BEST DIAGNOSIS IS GASTROSOPY & BIOPSY

57. PEPTIC ULCER Loss of tissue from the lining of the digestive tract. May be acute or chronic. Classified as gastric or duodental (stress- develop 24-48hr. After event) CAUSES : drugs, stress, heavy alcohol and tobacco use, infection (H .pylori bacteria) Conditions that cause high gastric acid concentration

58. TREATMENT Drug therapy Antacids H2 RECEPTOR BLOCKERS ANTICHOLINERGICS-Pro-Banthine, Robinul, Bentyl SUCRALFATE- Carafate Antibiotics – Flagyl, tetracycline, Biaxin treatment goals- relieve symptoms, promote healing, prevent complications and recurrence

59. STOMACH CANCER Rare(25,000/yr.), common in males, African American, over 70 and low socioeconomic status. 60% decrease in past 40 yrs. No S/S in early stages Late stages S/S: N/V, ascities , liver enlargement, abd . Mass Mets to bone and lung 10% survival rate after 5 yrs . Risk factors : pernicious anemia, chronic gastritis, cigarette smoking, diet high in starch, salt, salted meat, pickled foods, nitrates Treatment : surgery/ chemotherapy/ radiation subtotal gastrectomy , total gastrectomy

60. OBESITY Increase in body weight, 20% over ideal, caused by excessive fat. Morbid obesity twice ideal Causes: heredity, body build, metabolism, psychosocial factors. Calorie intake exceeds demands.

61. Treatment and nursing care Weight reduction diet drug therapy, mainly Amphetamines Surgical procedures: Liposuction Lipectomy Jaw wiring Intragastric balloon Gastric bypass gastroplasty jejunoileal bypass Nursing care-assessment, diet monitoring, education

62. DIRRHOEA The passage of loose liquid stools with increased frequency, associated with cramping, abd, pain Causes ; (many), foods, allergies, infections, stress, fecal impaction, tube feedings, medications Complications - usually temporary/ can be dehydration, malnutrition

63. Treatment/Nursing care Treatment; GI rest, antidiarrheal drugs(Lomotil, Imodium, Kaolin, Aluminum hydroxide) Nursing Care : help determine cause, assessVS, weight, skin turgor, abdominal destention, perianal irritation, skin integrity

64. CONSTIPATION HARD DRY INFREQUENT STOOLS PASSED WITH DIFFICULTY Causes : (many),inactivity, ignored urge, drugs,age related changes Complications : straining (Valsalva maneuver) and fecal impaction

65. Treatment/Nursing care Laxatives, suppositorys, enemas for prompt results stool softeners, increase fluids,dietary fiber Nursing care: assessment, monitor fluids and diet, education, check for impaction

66. Thank you…