NURS 504 Exam 3 High-Yield Review: Pulmonary, Renal, GI, and Musculoskeletal Pathophysiology

Comprehensive vocabulary flashcards covering the etiology, core pathophysiological mechanisms, clinical manifestations, and discriminators for pulmonary, renal, gastrointestinal, and musculoskeletal topics tested on Exam 3.

Ventilation-Perfusion ($V/Q$) Mismatch

A common mechanism of hypoxemia in which pulmonary ventilation and capillary blood flow are unequal; low $V/Q$ indicates perfusion exceeds ventilation, whereas high $V/Q$ indicates ventilation exceeds perfusion.

Pulmonary Shunt

A condition in which deoxygenated blood traverses poorly ventilated or non-ventilated alveoli without undergoing gas exchange, causing hypoxemia that responds poorly to supplemental oxygen therapy.

Alveolar Dead Space

Ventilated alveoli that receive little or no capillary blood perfusion, classically created by an occlusive vascular event such as a pulmonary embolism.

Hypoxemia

A reduction in the partial pressure of arterial blood oxygen, designated as a decreased $PaO_2$.

Hypoxia

Inadequate oxygen delivery, transport, or utilization at the cellular and tissue level, which can occur even when arterial $PaO_2$ is within normal limits.

Kussmaul Breathing

A deep, rapid respiratory pattern that acts as physiological respiratory compensation to lower $PaCO_2$ in response to metabolic acidosis.

Orthopnea

Dyspnea that develops when a patient is in a recumbent or supine position.

Paroxysmal Nocturnal Dyspnea (PND)

Sudden awakening from sleep with severe breathlessness, classically associated with pulmonary venous congestion secondary to left-sided heart failure.

Obstructive Lung Disease

Respiratory disorders characterized mechanically by expiratory airflow limitation and a decreased $FEV_1/FVC$ ratio resulting from narrowed or collapsible airways.

Restrictive Lung Disease

Respiratory disorders characterized mechanically by reduced lung expansion, decreased total lung capacity (TLC), and a normal or elevated $FEV_1/FVC$ ratio resulting from stiff lung tissue or limited chest-wall mobility.

Chronic Bronchitis

Chronic airway inflammation with hypertrophy of mucus glands and impaired clearance; clinically defined by a productive cough lasting for at least $3$ months in each of $2$ consecutive years after other causes are excluded.

Emphysema

Permanent abnormal enlargement of gas-exchange airspaces distal to terminal bronchioles accompanied by alveolar-wall destruction and loss of elastic recoil, leading to expiratory small-airway collapse and air trapping.

Panacinar Emphysema

A pattern of emphysematous destruction involving the entire acinus uniformly with lower-lobe predominance, classically associated with hereditary alpha-1 antitrypsin deficiency.

Centriacinar Emphysema

A pattern of emphysematous destruction predominantly affecting the central respiratory bronchioles with upper-lobe predominance, classically associated with cigarette smoking.

Acute Respiratory Distress Syndrome (ARDS)

Acute diffuse alveolocapillary injury characterized by increased microvascular permeability, surfactant inactivation, diffuse atelectasis, reduced pulmonary compliance, and refractory hypoxemia without primary left-sided heart failure.

Atelectasis

Alveolar collapse caused by external compression or gas absorption behind an obstruction, resulting in a reduced ventilated lung surface and low $V/Q$ or shunt physiology.

Cor Pulmonale

Right ventricular hypertrophy, dilation, and potential failure resulting from chronic pulmonary arterial hypertension caused by chronic pulmonary disease or hypoxemia.

Bronchiectasis

Persistent, irreversible abnormal dilation of the bronchi accompanied by chronic inflammation, impaired mucus clearance, and recurrent pulmonary infections.

Croup (Acute Laryngotracheobronchitis)

A viral upper-airway infection (commonly parainfluenza) that produces subglottic edema, characterized clinically by hoarseness, a barking seal-like cough, and inspiratory stridor in children.

Epiglottitis

A rapid, life-threatening supraglottic bacterial infection and inflammatory edema (classically caused by Haemophilus influenzae type b) marked by high fever, severe sore throat, drooling, inspiratory stridor, and severe distress.

Neonatal Respiratory Distress Syndrome (Neonatal RDS)

A neonatal pulmonary condition driven by prematurity and alveolar surfactant deficiency, resulting in high alveolar surface tension, diffuse microatelectasis, hypoxemia, and increased work of breathing.

Cystic Fibrosis

An autosomal recessive disorder caused by CFTR gene dysfunction that disrupts epithelial chloride, ion, and water transport, causing thick secretions, impaired mucociliary clearance, chronic lung infections, bronchiectasis, and exocrine pancreatic insufficiency.

Pneumoconiosis

A non-genetic, environmentally or occupationally acquired chronic fibrotic lung disease resulting from long-term inhalation of inorganic mineral dusts, including silica, coal dust, or asbestos.

Prerenal Acute Kidney Injury

An acute decline in glomerular filtration rate caused by impaired renal perfusion (e.g., dehydration, hemorrhage, shock) in which intact renal tubules retain sodium and water to maintain intravascular volume.

Intrinsic Acute Kidney Injury

Acute renal impairment resulting from direct structural or parenchymal damage to nephron tissue (such as acute tubular injury, glomerulonephritis, or interstitial nephritis), impairing solute reabsorption and urinary concentration.

Postrenal Acute Kidney Injury

Acute kidney dysfunction caused by bilateral mechanical or functional urinary tract outflow obstruction (e.g., calculi, prostatic enlargement), which elevates retrograde hydrostatic pressure and reduces net filtration.

Chronic Kidney Disease (CKD)

Persistent structural or functional kidney damage present for at least $3$ months, characterized by progressive nephron loss and compensatory hyperfiltration of remaining nephrons that ultimately drives secondary glomerular sclerosis.

CKD Mineral-Bone Disorder (CKD-MBD)

A systemic mineral and skeletal disorder in CKD initiated by phosphate retention, reduced calcitriol activation, and altered FGF23, leading to hypocalcemia and secondary hyperparathyroidism.

Nephritic Syndrome

A clinical complex of inflammatory glomerular barrier injury characterized by hematuria with dysmorphic red blood cells, RBC casts, hypertension, oliguria, and variable proteinuria.

Nephrotic Syndrome

A glomerular disorder characterized by podocyte and filtration-barrier injury resulting in massive proteinuria ($\ge 3.5\,\text{g/day}$ in adults), hypoalbuminemia, generalized edema, and hyperlipidemia.

Minimal Change Disease

The most common etiology of pediatric nephrotic syndrome, marked by podocyte foot-process effacement that causes heavy selective proteinuria, hypoalbuminemia, and peripheral edema.

Poststreptococcal Glomerulonephritis

An immune complex-mediated inflammatory glomerular injury developing after group A beta-hemolytic streptococcal infection, presenting with gross hematuria (cola-colored urine), RBC casts, hypertension, and edema.

Vesicoureteral Reflux (VUR)

Abnormal retrograde flow of urine from the urinary bladder upward into the ureters and renal collecting systems, predisposing children to ascending pyelonephritis and renal parenchymal scarring.

Hemolytic Uremic Syndrome (HUS)

A condition characterized by toxin-mediated endothelial injury (commonly following Shiga-toxin-producing Escherichia coli infection) that triggers microvascular thrombosis, resulting in the clinical triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury.

Wilms Tumor (Nephroblastoma)

An embryonal renal neoplasm of childhood typically manifesting as an asymptomatic, firm, enlarging abdominal flank mass.

Red Blood Cell (RBC) Casts

Microscopic cylindrical structures in the urinary sediment that represent red blood cells entrapped in tubular matrix, pathognomonic for active glomerular hemorrhage and glomerulonephritis.

White Blood Cell (WBC) Casts

Microscopic urinary cylinders of leukocytes formed within renal tubules, confirming inflammation or infection of the renal parenchyma and differentiating pyelonephritis from isolated cystitis.

Achalasia

An esophageal motility disorder caused by loss of inhibitory ganglion cells within the myenteric plexus, leading to absent esophageal peristalsis and failure of the lower esophageal sphincter to relax during swallowing.

Gastroesophageal Reflux Disease (GERD)

A condition in which incompetence of the lower esophageal sphincter allows retrograde flow of acidic gastric juice into the esophagus, producing heartburn, regurgitation, esophagitis, and Barrett metaplasia.

Crohn Disease

A chronic inflammatory bowel disease characterized by transmural inflammation and discontinuous skip lesions occurring anywhere along the alimentary canal from mouth to anus, predisposing to strictures, fistulas, and linear growth failure.

Ulcerative Colitis

A chronic inflammatory bowel disease confined to the mucosal and submucosal layers of the large intestine, extending continuously from the rectum proximally, characterized clinically by bloody diarrhea, urgency, and tenesmus.

Infantile Hypertrophic Pyloric Stenosis

Hypertrophy of the circular smooth muscle of the pylorus that mechanically obstructs gastric emptying, presenting with progressive nonbilious projectile vomiting and hypochloremic metabolic alkalosis.

Intussusception

The invagination or telescoping of one intestinal segment into an adjacent distal segment, obstructing venous outflow and causing bowel wall edema, intermittent colicky abdominal pain, and red currant-jelly stools.

Hirschsprung Disease

Congenital functional bowel obstruction caused by failure of neural crest cells to migrate, resulting in an aganglionic segment in the distal bowel, failure to pass meconium, and megacolon.

Necrotizing Enterocolitis (NEC)

An acute inflammatory and ischemic necrosis of the intestinal mucosa occurring predominantly in premature neonates, characterized by feeding intolerance, abdominal distention, and hematochezia.

Celiac Disease

An immune-mediated enteropathy triggered by ingested gluten peptides in genetically susceptible individuals, leading to small-intestinal villous blunting, crypt hyperplasia, and generalized nutrient malabsorption.

Hepatic Encephalopathy

A reversible neuropsychiatric complication of advanced chronic liver failure or portosystemic shunting, caused by accumulation of neurotoxins (including blood ammonia) and marked by asterixis, confusion, and altered sensorium.

Hepatorenal Syndrome

Reversible functional renal failure in advanced cirrhosis and portal hypertension, caused by profound renal arterial vasoconstriction triggered by severe splanchnic arterial vasodilation.

Osteoarthritis (OA)

A whole-joint degenerative disease driven by mechanical and biologic stress, characterized by progressive loss of articular cartilage, subchondral sclerosis, osteophyte formation, crepitus, and brief post-rest stiffness ($< 30\,\text{min}$).

Rheumatoid Arthritis (RA)

A chronic systemic autoimmune disease characterized by symmetric inflammatory synovitis, synovial proliferation, marginal articular erosions, and prolonged morning stiffness ($> 30\text{--}60\,\text{min}$).

Osteophytes

Reparative fibrocartilage-capped bony projections (bone spurs) formed at the margins of articulating surfaces in response to abnormal mechanical load and cartilage loss in osteoarthritis.

Osteoporosis

A systemic skeletal disorder characterized by low bone mineral density and deterioration of trabecular microarchitecture due to an imbalance where osteoclastic bone resorption exceeds osteoblastic bone formation.

Gout

A crystalline arthropathy initiated by precipitation of monosodium urate crystals in joint cavities, triggering innate immune activation through the inflammasome and interleukin-1 pathways to produce acute monoarticular inflammation.

Compartment Syndrome

A limb-threatening condition in which elevated interstitial tissue pressure within an unyielding osteofascial compartment exceeds capillary perfusion pressure, causing muscle and nerve ischemia while distal pulses may remain intact early.

Rhabdomyolysis

Rapid dissolution of damaged striated skeletal muscle fibers with release of intracellular components (creatine kinase, myoglobin, and potassium) into the systemic circulation, which risks myoglobinuric acute tubular injury and hyperkalemia.