Chapter 36: Digestive System Vocabulary Flashcards

Overview of the Digestive System

• Gastrointestinal Pathway:

  • Food follows a sequential directional path through the alimentary tract:     $\text{Food} \rightarrow \text{Mouth} \rightarrow \text{Pharynx} \rightarrow \text{Esophagus} \rightarrow \text{Stomach} \rightarrow \text{Small Intestine} \rightarrow \text{Large Intestine} \rightarrow \text{Rectum/Anus}$

• Role of Accessory Organs:

  • Salivary glands, liver, gallbladder, and pancreas produce enzymes, bile, and secretions necessary for digestion.

• Primary Objectives of Digestion:

  • Absorb essential nutrients required by the body.

  • Eliminate indigestible solid waste products.

Structural and Functional Anatomy of the Digestive Tract

• Mouth (Oral Cavity):

  • Functions:

  • Mechanically chews food into smaller pieces to facilitate digestion.

  • Saliva, produced by salivary glands, moistens food particles to ensure safe swallowing.

  • Certified Nursing Assistant (CNA) Observations and Reporting:

  • Assess denture fit, presence of mouth sores, or complaints of tooth pain.

  • Monitor for coughing or choking episodes during eating.

  • Report dry mouth or difficulties in chewing food.

• Pharynx and Esophagus:

  • Functions:

  • Moves food safely from the oral cavity into the stomach via peristaltic movement.

  • The epiglottis closes over the larynx during swallowing to prevent food and liquid from entering the respiratory airway.

• Anatomical Components Involved in Swallowing:

  • Tongue, soft palate, pharynx, larynx, epiglottis, windpipe (trachea), esophagus, and cervical vertebrae.

• CNA Observations and Reporting:

  • Observe for signs of swallowing difficulty (dysphagia) or elevated aspiration risk.

  • Note resident complaints of food 'sticking' in the throat or chest.

  • Report symptoms of heartburn or acid reflux.

• Stomach:

  • Functions:

  • Mixes ingested food with gastric acid and digestive enzymes to convert solid food into liquid 'chyme'.

  • Initiates the chemical breakdown of proteins.

• Anatomical Regions and Structures:

  • Regions: Cardia (junction with esophagus), Fundus, Body, Pyloric region (comprising pyloric antrum, pyloric canal, and pyloric sphincter leading into the duodenum).

  • Curvatures and Surface: Lesser curvature (medial surface), Greater curvature (lateral surface), Anterior surface, and Rugae (internal mucosal folds).

  • Muscular Layers: Longitudinal muscle layer, Circular muscle layer, and Oblique muscle layer overlying the mucosa.

  • Vascularization: Left gastroepiploic vessels.

• CNA Observations and Reporting:

  • Report complaints of stomach pain, nausea, or vomiting.

  • Immediately report black or tarry stools (melena), which indicate potential upper gastrointestinal bleeding.

  • Small Intestine:

• Functions:

  • Serves as the primary site for nutrient absorption into the bloodstream.

• Anatomical Subdivisions:

  • Duodenum: First C-shaped section receiving chyme, bile, and pancreatic enzymes.

  • Jejunum: Middle section focused on nutrient absorption.

  • Ileum: Final segment connecting to the large intestine.

• CNA Observations and Reporting:

  • Watch for unintended weight loss, physical weakness, or poor appetite.

  • Report diarrhea or frequent, loose stools.

  • Large Intestine (Colon):

• Functions:

  • Absorbs remaining water and essential minerals from indigestible material.

  • Forms and compacts stool for eventual elimination.

• Anatomical Subdivisions:

  • Cecum: Pouch at the beginning of the large intestine.

  • Ascending Colon: Travels upward on the right side of the abdomen.

  • Transverse Colon: Crosses the abdominal cavity horizontally.

  • Descending Colon: Travels downward on the left side of the abdomen.

  • Sigmoid Colon: S-shaped region leading into the rectum.

• CNA Observations and Reporting:

  • Monitor for constipation characterized by hard, dry stools or straining during defecation.

  • Note changes in normal bowel elimination patterns.

  • Report abdominal pain or bloating.

  • Rectum and Anus:

• Functions:

  • Stores stool prior to defecation and regulates its release through muscular sphincters.

• Anatomical Structures:

  • Rectum and Anal Canal: Terminal portions of the gastrointestinal tract.

  • Sphincter Muscles: Internal anal sphincter (involuntary control), External anal sphincter (voluntary control), and Puborectalis muscle.

  • Mucosal Landmarks: Anal columns, anal sinuses, pectinate (dentate) line, and anocutaneous line.

• CNA Observations and Reporting:

  • Observe for pain during bowel movements, presence of hemorrhoids, or bright red blood on toilet tissue.

  • Report new-onset fecal incontinence or signs of fecal impaction.

Digestive Accessory Organs

• Salivary Glands:

  • Produce saliva to moisten food, initiate starch breakdown, and assist in chewing and swallowing.

• Liver:

  • Functions:

  • Synthesizes bile necessary for lipid/fat digestion and emulsification.

  • Filters and detoxifies blood, removing foreign substances, drugs, and toxins.

  • Stores excess energy in the form of glycogen.

• Ductal System:

  • Right and left hepatic ducts merge into the common hepatic duct.

• CNA Observations and Reporting:

  • Watch for yellowing of the skin or sclera of the eyes (jaundice).

  • Note dark urine accompanied by pale or gray/clay-colored stools.

  • Immediately report new confusion or extreme fatigue, which may indicate hepatic dysfunction.

  • Gallbladder:

• Functions:

  • Stores and concentrates bile produced by the liver.

  • Releases stored bile into the small intestine following meal ingestion, particularly meals rich in dietary fats.

• Anatomical Parts:

  • Fundus, Body, Neck, and the Cystic Duct (which joins the common hepatic duct to form the common bile duct).

• CNA Observations and Reporting:

  • Report right upper quadrant abdominal pain, which may radiate to the back or right shoulder.

  • Monitor for nausea occurring after consumption of fatty foods.

  • Report pale or 'clay-colored' stools.

  • Pancreas:

• Functions:

  • Exocrine Role: Produces digestive enzymes released into the duodenum via the pancreatic duct (and accessory pancreatic duct) entering at the major and minor duodenal papillae.

  • Endocrine Role: Secretes hormones (insulin and glucagon) directly into the bloodstream to regulate blood glucose homeostasis.

• Anatomical Regions:

  • Head of Pancreas (nestled in the C-loop of the duodenum), Body of Pancreas, and Tail of Pancreas.

• CNA Observations and Reporting:

  • Urgent reporting required for severe upper abdominal pain accompanied by vomiting (indicative of acute pancreatitis).

  • In diabetic residents, report low appetite, vomiting, or unusual drowsiness immediately.

Physiological Aging Changes in the Digestive System

• Physiological Changes:

  • Decreased saliva production, leading to dry mouth (xerostomia), making chewing and swallowing more difficult.

  • Slower digestive motility and delayed gastric emptying.

  • Elevated risk for developing constipation.

• CNA Interventions and Care Strategies:

  • Encourage fluid intake and fiber consumption if permitted by physician orders.

  • Cut food into small, manageable pieces and allow adequate time for chewing and swallowing.

  • Report any difficulty swallowing (dysphagia) or painful chewing.

Common Gastrointestinal Disorders and Pathologies

• Peptic Ulcer Disease:

  • Pathophysiology:

  • Formation of painful sores or erosions in the mucosal lining of the stomach or duodenum.

  • Frequently caused by infection with Helicobacter pylori (H. pylori) bacteria or prolonged NSAID use.

  • Mucosal tissue layers involved include the mucosa, submucosa, and muscle layer.

  • Potential for active bleeding and severe pain.

• CNA Observations and Reporting:

  • Report new or worsening epigastric stomach pain.

  • Immediately report nausea, vomiting, or black/tarry stools.

  • Hernias, GERD, and Hiatal Hernia:

• Hernia Definition: Protrusion of an organ or tissue (such as the small intestine) through a weakness in the surrounding muscular wall.

• Types of Hernias:

  • Umbilical Hernia: Occurs near the navel.

  • Incisional Hernia: Occurs at the site of a previous surgical incision.

  • Inguinal Hernia: Occurs in the groin region, where small intestine pushes through the abdominal wall.

  • Femoral Hernia: Occurs in the upper thigh/groin junction.

• Hiatal Hernia and Gastroesophageal Reflux Disease (GERD):

  • Occurs when a portion of the upper stomach slides upward into the chest cavity through a weakened opening (hiatus) in the diaphragm.

  • Promotes acid reflux and heartburn due to dysfunction of the lower esophageal sphincter.

• CNA Observations and Reporting:

  • Observe for visible bulges or pain aggravated by lifting or straining.

  • Report heartburn; position residents upright during and after meals as ordered.

  • Gallbladder Disorders (Gallstones / Cholelithiasis):

• Pathophysiology:

  • Hardened deposits (gallstones) obstruct bile passages, such as the cystic duct or common bile duct.

  • Obstruction blocks normal bile flow, leading to localized inflammation, pain, and infection.

• CNA Observations and Reporting:

  • Watch for right upper quadrant abdominal pain following meals high in fat.

  • Report fever, nausea, and pale/clay-colored stools promptly.

  • Constipation:

• Pathophysiology:

  • Infrequent or difficult passaging of hard, dry stools resulting from slowed colonic transit, dehydration, or medication side effects.

• CNA Observations and Reporting:

  • Report absence of bowel movements for several consecutive days or reports of painful elimination.

  • Encourage fluid consumption, physical activity, and dietary fiber as authorized by care plans.

  • Safety Warning: Never administer laxatives unless specifically ordered by a healthcare provider.

  • Colorectal Cancer:

• Pathophysiology:

  • Malignant neoplasm occurring anywhere within the gastrointestinal tract, most commonly affecting the colon and rectum.

  • Staging Progression:

    • Stage 0 / Stage I: Localized carcinoma confined to inner layers.

    • Stage II / Stage III: Penetration through muscular wall into surrounding tissue and regional lymph nodes.

    • Stage IV: Metastatic spread through blood vessels to distant organs.

• CNA Observations and Reporting:

  • Watch for visible blood in stool or significant, persistent alterations in bowel habits.

  • Report unintended weight loss promptly.

CNA Role and Daily Care Protocols

• Every-Shift Responsibilities:

  • Observe and Document: Track dietary intake/appetite, nausea, vomiting episodes, and frequency/consistency of bowel elimination patterns.

  • Privacy and Dignity: Maintain resident privacy and dignity during all toileting and personal hygiene assistance.

  • Dietary Compliance: Ensure strict adherence to specialized diets (e.g., soft diet, low-fat diet, NPO [nothing by mouth]) according to physician orders.

  • Prompt Red Flag Reporting: Immediately report critical symptoms to the charge nurse:

  • Severe abdominal pain.

  • Bright red blood in stool.

  • Black, tarry stools (melena).

  • Jaundice (yellow skin or eyes).

Key Clinical Takeaways

• GI Tract Sequence: Master the sequential passage of food from mouth to anus, along with the supportive role of accessory organs.

• Absorption Specialization: Recognize that the small intestine handles the vast majority of nutrient absorption, whereas the colon primarily absorbs water and minerals.

• Constipation Vigilance: Understand that constipation is especially prevalent among older adults, requiring proactive prevention and early reporting.

• Impact of CNA Observation: Vigilant daily observations by nursing assistants are vital for detecting early clinical deterioration and preventing severe gastrointestinal complications.