Renal and Neurologic function
Exam Review
- Reviewing Incorrect Answers: Schedule an appointment to review exam questions, including incorrect answers, questions of concern, and correctly answered questions lacking full comprehension.
- Exam Scores: Scores released after everyone has completed the exam to address potential coding issues.
- Exam Format:
- 50 questions total.
- 50 minutes total (1 minute per question).
- Accommodations provided with proper documentation.
- No backtracking allowed to mimic licensing exams.
- Primarily single-response questions with a few fill-in-the-blanks.
Genetic Disorders
- Symptoms of Genetic Disorders: Expected to link symptoms to genetic changes.
- Example: Marfan Syndrome: Recognize genetic changes based on symptoms like hyperflexibility and pectus excavatum.
*Tay-Sachs Disease:
- Presentation: Unremarkable pregnancy followed by decreased milestones and potential seizures in infancy.
- Risk Factors: Higher risk in couples of the same ethnicity, particularly Ashkenazi Jewish descent.
Proctoring and Study Guide
- Proctoring Software: Use LockDown Browser without requiring additional downloads.
- Study Guide: A study guide will be provided, and students can ask questions about it.
- Contact: Available via Zoom or email for questions or review.
- Review Sessions: Email to schedule review sessions.
Acid-Base Regulation
- Respiratory System: Manages pH by altering breathing rate and depth, affecting CO_2 excretion or retention.
- Decreased respiratory rate: Increased CO_2 and acidity.
- Quick response but brief effect.
- Renal System: Regulates pH by excreting or retaining hydrogen or bicarbonate in urine.
- More effective due to permanent removal of hydrogen.
- Slower response but longer-lasting effect.
- Normal Values:
- pH: 7.35 - 7.45
- PaO_2: 95 - 100
- PaCO_2: 35 - 45
- Bicarbonate (HCO_3): 22 - 26
Blood Gas Analysis Examples
- pH 7.25, CO2 56, PaO2 99, Bicarbonate 24: Respiratory acidosis, uncompensated.
- pH 7.54, CO2 24, PaO2 98, Bicarbonate 23: Respiratory alkalosis, uncompensated.
- pH 7.36, CO2 54, PaO2 95, Bicarbonate 29: Compensated respiratory acidosis (pH normal).
- pH 7.31, CO2 56, PaO2 99, Bicarbonate 28: Partially compensated respiratory acidosis (pH still acidotic).
Electrolytes
- Sodium (Na): Most abundant cation in extracellular fluid; controls osmolality and water balance.
- Normal Range: 135 - 145 mEq/L
- Hypernatremia: Excessive sodium; caused by iatrogenic factors, Cushing's syndrome, deficient water intake, etc.
- Hyponatremia: Insufficient sodium; caused by diuretic use, GI losses, excessive water intake, liver failure, etc.
- Potassium (K): Primary intracellular cation; critical for electrical conduction, acid-base balance, and metabolism.
- Normal Range: 3.5 - 5.5 mEq/L
- Hyperkalemia: Excessive potassium; caused by deficient excretion (renal failure), certain medications, or increased release from cells (acidosis, blood transfusions).
- Management: Diuretics (for responsive patients), calcium (to stabilize myocardium), insulin and dextrose (to shift K+ into cells), K+ oxalate (to eliminate K+ via GI tract), renal replacement therapy (for life-threatening cases).
- Indications for Dialysis: Life-threatening hyperkalemia, hyperammonemia, severe metabolic acidosis, significant fluid overload.
- Hypokalemia: Insufficient potassium; caused by excessive losses (vomiting, diarrhea, diuretics) or increased shifts into cells (alkalosis, excess insulin).
- Calcium (Ca): Important for various physiological processes.
- Hypercalcemia: Excessive calcium; caused by antacids, supplements, cancer (bone breakdown), or deficient excretion (renal failure).
- Hypocalcemia: Insufficient calcium; can lead to neonatal seizures.
- Etiologies: Hypoparathyroidism, alkalosis, pancreatitis, certain medications.
Fluid Balance
- Intracellular Fluid: Fluid inside cells.
- Intravascular Fluid: Fluid in the vascular system.
- Extravascular Fluid: Fluid outside the vascular system (e.g., ascites).
- Management of Hypotensive, Fluid-Overloaded Patients:
- Administer albumin or FFP to increase intravascular oncotic pressure.
- Use diuretics judiciously.
- Consider the risk of capillary leak in septic patients when administering albumin.
Fluid Abnormalities
- Fluid Excess: Caused by excessive intake or retention; increased ADH increases water reabsorption.
*Monitoring: Weights (most accurate), INO (intake and output). - Fluid Deficit: Caused by excessive loss.
- Manifestations: Weight loss, dizziness.
IV Fluid Solutions
- Isotonic: Same osmolality as intravascular compartment (e.g., normal saline, lactated Ringer's).
- Hypotonic: Lower osmolality; causes fluid shift from intravascular to intracellular/interstitial (e.g., half-normal saline).
- Hypertonic: Higher osmolality; pulls fluid from the interstitial to the vascular space (e.g., D5 normal saline, 3% saline, mannitol).
Edema
- Definition: Result of hydrostatic pressure on the venous side of the capillary, causing fluid movement into the interstitial space.
- Causes:
- Lack of movement
- Heart failure
- Dependent edema
- Deep vein thrombosis (DVT): Typically unilateral, increases hydrostatic pressure.
- Management:
- Diuretics
- Mobilization
- Compression stockings
Renal System Anatomy and Function
- Components: Kidneys, ureters, bladder, urethra.
- Nephron: Functional unit of the kidney; filters substances; glomerulus filters blood.
- Glomerular Filtration Rate (GFR): Best indicator of renal function.
- Kidney Functions:
- Regulate urine and fluid volume.
- Regulate blood pressure (RAS system, ADH).
- Excrete metabolic waste.
- Conserve nutrients.
- Excrete drugs.
- Convert vitamin D.
- Maintain pH balance.
- Synthesize hormones (renin, erythropoietin).
- Kidneys and Hypertension: Kidneys play a significant role in blood pressure regulation.
- Drug Excretion: Adjust medication dosages based on GFR or creatinine clearance to avoid unintended consequences.
Urinalysis (UA)
- Components: pH, specific gravity, urine sedimentation, red blood cells, crystals, casts.
- Casts:
- Red Cell Casts: Indicate renal tubule bleeding or red cells escaping through the glomerulus (associated with AKI, ATN).
- White Cell Casts: Indicate an inflammatory process.
- Epithelial Casts: Indicate degeneration or necrosis of renal tubules.
- UTI and Pyelonephritis:
- Cystitis: Inflammation of the bladder and urethra, often bacterial.
- Pyelonephritis: Infection ascends to one or both kidneys, causing edema and potential abscesses or necrosis.
- Symptoms: Fever and a lot more systemic signs and symptoms. Can also compress the renal artery with resulting ischemia and infarction.