Applied Pathophysiology: Altered Urinary Elimination PDF

Lecture Material is adapted from © 2022 Wolters Kluwer Health, Lippincott Williams & Wilkins Applied Pathophysiology: A Conceptual Approach to the Mechanisms of Disease Chapter 18: Altered Elimination Module 1: Altered Urinary Elimination Dr. Romeo Batacan Jr. MPAT12001 Medical Pathophysiology L...

Lecture Material is adapted from © 2022 Wolters Kluwer Health, Lippincott Williams & Wilkins Applied Pathophysiology: A Conceptual Approach to the Mechanisms of Disease Chapter 18: Altered Elimination Module 1: Altered Urinary Elimination Dr. Romeo Batacan Jr. MPAT12001 Medical Pathophysiology Lecture Series Copyright © 2017 Wolters Kluwer Health | Lippincott Williams &Wilkins Altered Urinary Elimination neural, vascular, muscular, and hormonal influences movement of urine from its production to its exit must be patent and functional Altered Urinary Elimination Altered motility: reduced contraction of hollow structures promote stasis of filtrate in the renal tubules promote stasis of urine in the bladder which may promote growth of bacteria and infection in the kidneys Stasis leads to altered reabsorption and secretion: increased sodium concentration, low pH casts formation, precipitation of urinary fluid components and obstruction Trapping of RBCs within casts: glomerulonephritis (inflammation of glomerulus) Trapping of epithelial cells within casts: acute tubular necrosis (sloughing of tubular cells) Trapping of WBCs within casts: pyelonephritis (kidney infection and inflammation) Altered Urinary Elimination Altered neuromuscular function: impaired neural control of urinary elimination and inappropriate muscle response (peristalsis of the renal tubules) Impaired neural control involves neurons of the peripheral and central nervous systems neurotransmitter production and availability coordination of neural impulses from initiation to action failure to provide an appropriate stimulus: limited or absent ability to eliminate urine, urinary retention exaggerated response: premature release urine, urinary incontinence Altered Urinary Elimination Altered perfusion 1. Decreased perfusion excessive constriction of arterioles inadequate vascular volume obstructed patency of the arterial supply (an embolism) Decreased oxygen delivery: damage to renal structures because of inability to meet metabolic demands Loss of functional tissue through necrosis: pain, bleeding, obstruction of the branches of the venous system 2. Enhanced perfusion additional workload may stress the individual organ system Altered Urinary Elimination Altered patency or obstruction: blockage of structures Characterized by buildup of pressure behind the blockage Consequences Blockage of urine flow Dilation of structures proximal to obstruction Injury to renal anatomy Causes of blockage precipitation of substances in smaller lumen structures (casts etc.) structural blockage: polyps or tumors mechanical obstructions: urine precipitation, scar tissue, adhesions, inflammation Altered Urinary Elimination Dilation of the structures proximal to the obstruction: Stasis of urine Infection, structural damage Hydroureter: accumulation of fluid in the urinary ureter (complete ureteral obstruction) Hydronephrosis: increased hydrostatic pressure extending up to the renal pelvis and tubules impaired renal function fluid escapes from the tubules into the surrounding capillary system impaired excretion of sodium, urea, water Prolonged or severe pressure causes structural damage and impaired function  Manifestations of Altered Urinary Elimination Specific manifestations are related to the underlying pathology General manifestations are: Altered urinary volume Altered urinary composition Bleeding Pain General malaise Fever GI symptoms Manifestations of Altered Urinary Elimination Pain: frequent symptom associated with altered renal and urinary function Stimulated by stretching and inflammation in the renal capsule (rather than kidney itself) Pain receptors in the renal capsule: sensation of dull, persistent pain Pain receptors in the remaining parts of the urinary system: intermittent and sharp Manifestations of urinary infection: lower and upper urinary tract general malaise anorexia fever nausea vomiting Ascending infection: potential for renal structural damage affecting the ability to produce urine Diagnosis of Conditions of the Renal and Urinary Systems Diagnosis of the cause and effect of altered elimination Microscopic and macroscopic urinalysis Urinary electrolytes normal values not standardized kidneys dynamically maintain electrolyte homeostasis in the plasma GFR and creatinine clearance nephron function Radiographic diagnostic testing anatomic and functional anomalies Diagnosis of Conditions of the Renal and Urinary Systems Intravenous pyelogram (IVP) Intravenous injection of a radiocontrast medium to visualize the kidneys, ureters, and bladder Voiding cystourethrogram (VCUG) X‐ray examination of the bladder and urethra after https://www.nlm.nih.gov/medlineplus/ency/imagepages/19245.htm insertion of contrast into bladder via a urinary catheter Fluoroscopy is used to determine ureteral reflux and bladder/urethra configuration during voiding https://www.nlm.nih.gov/medlineplus/ency/imagepages/1144.htm Diagnosis of Conditions of the Renal and Urinary Systems Renal angiogram Contrast injected into the renal artery via the aorta to diagnose renal artery stenosis or intrarenal vascular obstructions Renal ultrasound Determine kidney size, hydroureter, cysts, obstructions, or fluid collection https://www.nlm.nih.gov/medlineplus/ency/imagepages/9818.htm Renal artery flow can also be determined with Doppler ultrasound  Treatment of Altered Elimination Treatment options depends on underlying cause often associated with impaired regulation of fluid balance administration of supplemental fluids to correct body fluid deficit use of diuretics to correct body fluid excess Lecture Material is adapted from © 2022 Wolters Kluwer Health, Lippincott Williams & Wilkins Applied Pathophysiology: A Conceptual Approach to the Mechanisms of Disease Chapter 18: Altered Elimination Module 2: Altered Stool Elimination Dr. Romeo Batacan Jr. MPAT12001 Medical Pathophysiology Lecture Series Copyright © 2017 Wolters Kluwer Health | Lippincott Williams &Wilkins Altered Stool Elimination Impaired large intestine function altered final steps of retrieval of water and electrolytes from the fecal matter altered absorption of vitamins produced by intestinal bacterial flora Stool elimination forward movement of fecal matter and propelling the intestinal contents towards the anus leaving the body as stool through the process of defecation Altered Stool Elimination Motility: determines the rate that fecal matter passes through for evacuation Increased motility: diarrhoea shortened transit time impair nutrition, prevents adequate nutrient and water absorption enhance loss of water and electrolytes Decreased motility: constipation slowed, increased transit time prolongs storage time in the large intestine promotes enhanced loss of fluid from fecal matter risk of obstruction potentially promotes the return of waste products to the circulation Bacterial intestinal flora influence motility Promotes motility: Lactobacillus acidophilus, Bifidobacterium bifidum Inhibits motility: Escherichia coli Altered Stool Elimination Altered neuromuscular function: impaired neural control of stool elimination and inappropriate muscle response (peristalsis of the GI tract) Impaired neural control involves neurons of the peripheral and central nervous systems neurotransmitter production and availability coordination of neural impulses from initiation to action failure to provide an appropriate stimulus: limited or absent ability to eliminate stool exaggerated response: pass stool unexpectedly, bowel incontinence Altered Stool Elimination Impaired neuromuscular function with loss of propulsive activity abdominal surgery electrolyte imbalances affecting contractile function peritonitis spinal trauma side effect of narcotic analgesia. emotional stress Reduced propulsive activity: impact defecation More time feces in the large intestine >> more water is removed, stool harder Passing of flatus is impaired >> distention of the abdomen, pain, obstruction Enhanced neuromuscular function Exercise (promotes peristalsis and bowel elimination)  Altered Stool Elimination Altered perfusion 1. Decreased perfusion ‐ ischemia often manifested by pain and altered bowel function Altered local circulation ‐ clot ‐ pressure from a space‐occupying mass ‐ erosion of blood vessels supplying perfusion to the intestine (ulceration or trauma) Altered global circulation: many etiologies ‐ blood is redistributed away from the digestive system to the vital organs 2. Excessive perfusion demands infection  Appendicitis A common infection of the GI system: appendicitis trapped fecal material in the appendix of the colon trapped infectious bacteria Unable to empty content Acute inflammation appendix swells squeezing off venous drainage ischemia (local decrease of blood supply) and necrosis if ruptures: feces containing bacteria cause peritonitis Marieb EN, Hoehn KN. Human Anatomy & Physiology. 9th ed. Boston, Pearson Education; 2013 Altered Elimination Altered patency: bowel obstruction space‐occupying lesion which blocks the non‐space occupying lesion intestinal lumen, either partially or totally herniation, adhesion, volvulus, intussusception common space‐occupying lesions tumors, polyps, impacted feces Altered Elimination Altered patency: Bowel obstruction associated with fluid and gas accumulation bowel obstruction is manifested by abdominal distention and pain Major effects: abdominal distention, loss of fluids and electrolytes (vomiting), gas and fluid accumulation, further distention causing pain, ischemia and necrosis, perforation, sepsis space‐occupying lesion that impairs capacity for venous return causes fluid to leak into the peritoneum Porth C. Pathophysiology : concepts of altered health states. 7th ed. Philadelphia, Lippincott Williams & Wilkins; 2005. General Manifestations of Altered Bowel Elimination Altered bowel sounds: auscultation reflection of intestinal smooth muscle contractions that are active intermittently quality, location, frequency of bowel sounds indication of peristaltic function For example: increased motility diarrhea Altered abdomen appearance Abdomen should be soft when pressed or palpated and flat relative to body size Abdominal size increase: trapping of gas > hardening and tightening of the abdomen normally the gaseous byproducts of digestion (flatus) are passed indicating bowel function General Manifestations of Altered Bowel Elimination Altered volume and characteristics of stool Diarrhea: loose, watery stools May be due to bowel inflammation, infection, increased motility Constipation: absence of bowel movement May be due to impaired mobility or obstruction Altered color changes due to specific disease states Bright red blood around stool – hemorrhoids Large frank red blood – internal bleeding in colon cancer Light colored (absence of bile) – hepatitis, malabsorption syndromes Black stool (melena) ‐ bleeding higher up in the GI system General Manifestations of Altered Bowel Elimination Altered stool texture Watery, hard, stringy, fatty, foul odor Pain – characteristic of intestinal disorders; mechanical, inflammatory, ischemic causes Anorexia (loss of appetite), nausea, vomiting general and do not point to a specific condition Abdominal distention: increased pressure due to fluid or feces in the bowel lumen, inflammation and edema of the intestine, increased production of gas Fever: infection peritonitis (inflammation of the peritoneal membrane  Diagnosis of Altered Elimination Stool analysis: microscopic analysis or culture of stool Bacteria or parasites: to determine the specific organism involved Fat content: the presence or absence of a disorder of malabsorption Occult (too small to be seen) blood Guaiac test small sample on a collection card and applying a chemical solution color change (blue) indicates the presence or absence of blood Immunochemical method uses antibodies directed against human hemoglobin  Diagnosis of Altered Elimination Mechanical obstructions: visualization techniques Barium enema colon and rectal anatomic abnormalities with the aid of contrast medium (barium) that is inserted via the anus visualization of the rectum and colon is completed by radiograph diverticulitis, alterations in motility, obstruction, and colon dimensions https://www.nlm.nih.gov/medlineplus/ency/imagepages/1064.htm Diagnosis of Altered Elimination Sigmoidoscopy insertion of a flexible tube into the anus rectum and the lower colon Colonoscopy insertion of a flexible tube into the anus entire colon, from the small intestine to the rectum Treatment of Altered Bowel Elimination Diarrhea: excessive GI elimination Antidiarrheal drugs: to diminish fluid loss 1. Slowing the passage of stool through the intestine Antimotility agents: Promotes water removal from fecal matter, useful for chronic conditions 2. Moving diarrhea‐causing factors out of the stool Adsorbents: May also pull out other essential products 3. Decreasing secretion of fluid into intestine Reduce inflammatory response to pathogens (antibiotics), decreases fluid movement into intestinal contents 4. Using bulk‐forming agents Absorbs excess fluid, firms stool Treatment of Altered Bowel Elimination Constipation: decreased GI elimination exercise high dietary fiber adequate fluid intake stool softeners: promote moisture content in stool without the stimulant effect laxatives enemas: fluid injection into lower bowel through the rectum Obstructive abnormalities: surgical treatment for removal Alterations in neuromuscular function: assistive devices or https://www.nlm.nih.gov/medlineplus/e ncy/imagepages/9439.htm bowel training programs for elimination stool