GI Anaphy and Diagnostic

Digestive system

consists of the GI tract and its associated organs and glands

GI Tract

mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus

Associated organs

Liver, pancreas, and gallbladder

7 to 7.9 meters (23 to 26 feet)

How long is GI tract in length from mouth to anus

Esophagus

• Located in the mediastinum, anterior to the spine and posterior to the trachea and heart.

• A hollow muscular tube, which is approximately 25 cm (10 inches) in length, passes through the diaphragm at an opening called the diaphragmatic hiatus

Stomach

• vsituated in the upper portion of the abdomen to the left of the midline, just under the left diaphragm.

• It is a distensible pouch.

1500 mL

Esophagogastric junction

what is the inlet called

Lower esophageal sphincter

ring of smooth muscle surrounding the esophagogastric junction, aka cardiac sphicter, closes off the stomach from the esophagus

Cardia, fundus, body, pylorus

Stomach can be divided into four anatomic regions

Pyloric sphincter

Circular smooth muscle in the wall of the pylorus forms the pyloric ______ and controls the opening between the stomach and the small intestine

Small intestine

• The longest segment of the GI tract, accounting for about two thirds of the total length.

• It folds back and forth on itself

7000 cm

What is the approximate surface area for small intestine

Secretion and Absorption

process by which nutrients enter the bloodstream through the intestinal walls in small intestine

Duodenum, jejunum, ileum

Three anatomic parts of small intestine

Duodenum

upper part of small intestine

Jejunum

Middle part

Ileum

Lower part of small intestine

Common bile duct

allows for the passage of both bile and pancreatic secretions, empties into the duodenum at the ampulla of Vater.

Cecum

junction between the small and large intestine; located in the right lower portion of the abdomen.

Ileocecal valve

is located at this junction. It controls the passage of intestinal contents into the large intestine and prevents reflux of bacteria into the small intestine. ◼ The vermiform

Vermiform appendix

Large intestine

consists of ascending segment, tranverse segment, descending segment, sigmoid colon, rectum, anus, anal outlet

Ascending segment

on the right side of the abdomen

Transverse segment

extends from right to left in the upper abdomen

Descending segment

on the left side of the abdomen.

Terminal portion

what part of the large intestine consists of sigmoid colon and rectum

Anus

Rectum is continuous with the ______

Anal outlet

A network of striated muscle that forms both the internal and the external anal sphincters regulates the ______

Thoracic and abdominal aorta (Gastric artery, superior and inferior mesenteric arteries)

The GI tract receives blood from arteries that originate along the entire length of the

Gastric artery

Oxygen and nutrients are supplied to the stomach by what artery

Mesenteric artery

Oxygen and nutrients are supplied to the intestine by what artery

Portal vein

Blood is drained from these organs by veins that merge with others in the abdomen to form a large vessel called what

Then carried to the liver

20%

The blood flow to the GI tract is about ____ of the total cardiac output and increases significantly after eating.

Under esophagus and external anal sphincter

Portions of the tract that are under voluntary control

Sympathetic nerve stimulation

Inhibitory effect and Decreasing gastric secretion and motility and causing the sphincters and blood vessels to constrict

Parasympathetic nerve stimulation

Promotes peristalsis and increases secretory activities.

The sphincters relax under the influence of parasympathetic stimulation

Digestion, Absorption, Elimination

Major functions of the GI tract include

Digestion

phase of the digestive process that occurs when enzymes mix with ingested food and when proteins, fats, and sugars are broken down into their component molecules

Absorption

phase of the digestive process that occurs when small molecules, vitamins, and minerals pass through the walls of the small and large intestine and into the bloodstream

Elimination

phase of the digestive process that occurs after digestion and absorption, when waste products are eliminated from the body

Saliva, salivary amylase

Major enzymes and secretions of mouth

Hydrochloric acid, pepsin, intrinsic factor

Major enzymes and secretions of stomach

Amylase, lipase, trypsin, bile

Major enzymes and secretions of small intestine

Ptaylin (salivary amylase

Salivary glands

Starch →dextrin, maltose, glucose

Amylase

Pancreas and intestinal mucosa

Starch → dextrin, maltose, glucose

Maltase

Intestinal mucosa

Maltose → glucose

Sucrase

Intestinal mucosa

Sucrose → glucose, fructose

Lactase

Intestinal mucosa

Lactase → glucose, galactose

Pepsin

Gastric mucosa

Protein → polypeptides

Trypsin

Pancreas

Proteins and polypeptides → polypeptides, dipeptides, amino acids

Aminopeptides

Intestinal mucosa

Polypeptides → dipeptides, amino acids

Dipeptidase

Intestinal mucosa

Dipeptides → amino acids

Hydrochloric acid

Gastric mucosa

Protein → polypeptides, amino acids

Pharyngeal lipase

Pharynx mucosa

Triglycerides → fatty acids, diglycerides, monoglycerides

Steapsin

Gastric mucosa

Triglycerides → fatty acids, diglycerides, monoglycerides

Pancreatic lipase

Pancreas

Triglycerides → fatty acids, diglycerides, monoglycerides

Bile

Liver and gallbladder

Fat emulsification

Chewing

• The process of digestion begins with the act of ______, in which food is broken down into small particles that can be swallowed and mixed with digestive enzymes.

• Eating—or even the sight, smell, or taste of food—can cause reflex salivation.

1.5 L

• Approximately ____ of saliva is secreted daily from the parotid, the submaxillary, and the sublingual glands.

Ptyalin, or salivary amylase

is an enzyme that begins the digestion of starches.

Water and mucus,

also contained in saliva, help lubricate the food as it is chewed, thereby facilitating swallowing.

Swallowing

• begins as a voluntary act that is regulated by the swallowing center in the medulla oblongata of the central nervous system (CNS).

• As a bolus of food is _____, the epiglottis moves to cover the tracheal opening and prevent aspiration of food into the lungs.

• ______, which propels the bolus of food into the upper esophagus, thus ends as a reflex action

esophageal peristalsis

• The smooth muscle in the wall of the esophagus contracts in a rhythmic sequence from the upper esophagus toward the stomach to propel the bolus of food along the tract.

• During this process of ______, the lower esophageal sphincter relaxes and permits the bolus of food to enter the stomach.

• Subsequently, the lower esophageal sphincter closes tightly to prevent reflux of stomach contents into the esophagus

Voluntary Phase

a bolus of food is pushed by the tongue against the hard and soft palates and posteriorly toward the oropharynx

Pharyngeal phase

soft palate is elevated, closing off the nasopharynx. pharynx and larynx are elevated

Esophageal phase

Bolus is moved by peristaltic constractions of the esophagus toward the stomach

Health History

• Include all information related to GI function

• Abdominal pain, dyspepsia, gas, nausea and vomiting, constipation, diarrhea, fecal continence, change in bowel patterns, characteristics of stool, jaundice, history of GI surgery or problems, appetite and eating patterns, teeth, and nutritional assessment, including weight patterns

• Psychosocial, spiritual, and cultural factors

• Assess knowledge; need for patient education

Pain

a major symptom of GI disease

• abdominal ___ is a common presentation in the ambulatory setting

• Assessment:

  • Character

  • Duration

  • Pattern

  • Frequency

  • Location

  • Distribution of referred pain

  • Time of the pain

• Factors:

  • Meals

  • Rest

  • Activity

  • Defecation patter

Dyspepsia

• upper abdominal discomfort associated with eating (commonly called indigestion)—is the most common symptom of patients with GI dysfunction.

• Indigestion is an imprecise term that refers to a host of upper abdominal or epigastric symptoms such as pain, discomfort, fullness, bloating, early satiety, belching, heartburn, or regurgitation

• Causes:

  • Fatty foods

  • Salads

  • Coarse vegetables

  • Highly seasoned foods

Intestinal Gas

• The accumulation of gas in the GI tract may result in belching or flatulence

• Usually, gases in the small intestine pass into the colon and are released as flatus.

• Patients often complain of bloating, distention, or feeling “full of gas” with excessive flatulence as a symptom of food intolerance or gallbladder diseas

Belching

expulsion of gas from the stomach through the mouth

Flatulence

expulsion of gas from the rectum

Nausea

is a vague, uncomfortable sensation of sickness or “queasiness” that may or may not be followed by vomiting. It can be triggered by odors, activity, medications, or food intake.

Vomiting

is a physiologic protective response that limits the effects of noxious agents by emptying the stomach contents and sections of the small intestine

Distention of the duodenum or upper intestinal tract

is a common cause of nausea; it may also be an early warning sign of a pathologic process.

Nausea and vomiting

Causes:

• visceral afferent stimulation

• CNS disorders

• irritation of the chemoreceptor trigger zone from radiation therapy, systemic disorders, and endogenous and exogenous toxins, which may include specific classes of drugs

Change in bowel habits

may signal colonic dysfunction or disease.

Diarrhea

an abnormal increase in the frequency and liquidity of the stool or in daily stool weight or volume, commonly occurs when the contents move so rapidly through the intestine and colon that there is inadequate time for the GI secretions and oral contents to be absorbed.

• Typically associated with abdominal pain or cramping and nausea or vomiting.

Constipation

a decrease in the frequency of stool, or stools that are hard, dry, and of smaller volume than typical—may be associated with anal discomfort and rectal bleeding, and is a frequent reason patients seek health care referrals

Light to dark brown

Stool is normally ______. however, specific disease processes and ingestion of certain foods and medications may change the appearance of stool.

Melena

• tarry black color

• blood is shed in sufficient quantities into the upper GI tract

Bright or dark red

blood entering the lower portion of the GI tract or passing rapidly through it, what color stool

Lower rectal or anal bleeding

is suspected if there is streaking of blood on the surface of the stool or if blood is noted on toilet tissue

Bulky, greasy, foamy stools

that are foul in oder and may or may not float

Light gray or clay colored stool

Caused by a decrease or absence of conjugated bilirubin

Stool with mucus threads or pus

that may be visible on gross inspection of the stool

Small, dry, rock-hard masses

occasionally streaked with blood

Loose, watery stool

that may or may not be streaked with blood

Leafy green vegetables, spinach, kale

green poop

Beets, red gelatin, tomato soup, food coloring

Red poop

Bismuth, iron, black licorice

Black poop

Barium

Milky white poop

PAST HEALTH, FAMILY, AND SOCIAL HISTORY

• Recent history of sore throat or bloody sputum

• Discomfort caused by certain foods; daily food intake

• Use of alcohol and tobacco, including smokeless chewing tobacco

• Past and current medication use, and any previous diagnostic studies, treatments, or surgery are noted.

• Current nutritional status is assessed via history; laboratory tests (complete metabolic panel including liver function studies, triglyceride, iron studies, and complete blood count [CBC]) are obtained.

• History of the use of tobacco and alcohol includes details about type, amount, length of use, and the date of discontinuation, if any.

• Changes in appetite or eating patterns and any unexplained weight gain or loss over the past year.

• Psychosocial, spiritual, or cultural factors

MEDICATIONS

• Assess the patient’s past and current use of medications. Include information about probiotics and nutrition supplements.

• Many medications cause side effects in the GI system.

• GI problems can affect drug absorption and effectiveness.

• Antacids and laxatives may affect medication absorption.

• Many chemicals, herbal supplements, and drugs may be hepatotoxic.

• Examples include chronic high doses of acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs).

• NSAIDs may also cause upper GI bleeding, with an increasing risk as the person ages.

• Antibiotics, may change the normal bacterial composition in the GI tract, resulting in diarrhea

Surgery or other treatments

• Hospitalizations for any problems related to the GI system.

• Record any abdominal or rectal surgery, including the year, reason for surgery, postoperative course, and blood transfusions.

Appendectomy

Removal of appendix

Cholecystectomy

Removal of gallbladder

Choledochojejunostomy

Opening between common bile duct and jejunum

Choledocholithotomy

Opening into common bile duct for removal of stones