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ATI Engage Fundamentals

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Electrolytes

  • Definition: Minerals in the body that conduct electricity.

  • Locations: Found in urine, blood, tissues, and other body fluids.

  • Common Electrolytes Include:

    • Potassium (K+)

    • Sodium (Na+)

    • Calcium (Ca2+)

    • Magnesium (Mg2+)

  • Sources: Naturally occurring in the body and in food, drinks, and supplements.

Roles of Electrolytes

  • Hydration: Balancing the amount of water in the body.

  • pH Balance: Regulating the body’s pH (acid/base) level.

  • Waste Removal: Moving waste out of body cells.

  • Nutrient Transport: Moving nutrients into body cells.

  • Body Functionality: Allowing the body’s muscles, heart, nerves, and brain to function properly.

Dehydration

  • Critical Importance: The human body is comprised of 50%-66% water.

  • Occurrence: When the person cannot drink enough fluids to compensate for excessive water loss.

Thirst Mechanism

  • Trigger: Stimulation of nerve centers in the brain indicating the need for water.

  • Hormonal Response: The pituitary gland secretes vasopressin (antidiuretic hormone) to help conserve water by reducing urine production.

Electrolyte Imbalance

  • Causes of Imbalance Include:

    • Dehydration

    • Overhydration

    • Certain medications

    • History of heart, kidney, or liver disorders

    • Incorrect intravenous fluids or feedings.

Normal Electrolyte Values

  • Potassium (K+): 3.5-5.1 mEq/L

  • Sodium (Na+): 135-145 mEq/L

  • Calcium (Ca2+): 8.5-10.5 mg/dL

  • Magnesium (Mg2+): 1.8-2.2 mg/dL

Potassium and Sodium

  • Potassium (K+):

    • Role: Assists with nerve and muscle cell functions, crucial for muscle cells in the heart.

    • Hypokalemia: Low potassium levels.

    • Hyperkalemia: High potassium levels.

  • Sodium (Na+):

    • Role: Supports nerve and muscle function, maintains blood pressure, regulates fluid balance.

    • Hyponatremia: Low sodium levels.

    • Hypernatremia: High sodium levels.

Calcium

  • Function: Maintains strong bones; stored in teeth and bones for hardness.

  • Roles: Muscle movement, nerve impulse transmission, blood circulation.

  • Hypocalcemia: Low calcium levels, often due to hypoparathyroidism.

  • Hypercalcemia: High calcium levels, often due to hyperparathyroidism.

Magnesium

  • Role: Regulates nerve and muscle function, blood pressure, blood sugar levels; essential in the formation of bone, protein, and DNA.

  • Hypomagnesemia: Low magnesium levels.

  • Hypermagnesemia: High magnesium levels.

Hypovolemia

  • Definition: Decrease in blood volume due to loss of body fluids or blood.

  • Causes: Excessive sweating, large burns, diuretics, inadequate fluid intake, increased urination.

  • Initial Symptoms: Dryness of mucous membranes, decreased urine output, loss of skin elasticity.

  • Compensatory Mechanisms: Increased heart rate, stronger heart contractions, constriction of blood vessels in extremities to maintain blood flow to vital organs (heart, brain, kidneys).

Untreated Hypovolemia Symptoms

  • Symptoms may include:

    • Blue discoloration of lips/nail beds

    • Altered alertness or consciousness

    • Chest pain or tightness

    • Palpitations

    • Anuria: No urine production

    • Tachycardia: Increased heart rate

    • Tachypnea: Rapid breathing

    • Hypotension: Decreased blood pressure

    • Weak pulse

Hypovolemic Shock

  • Definition: Occurs when the body loses 20% (or one-fifth) of its blood or fluid supply.

  • Treatment: Focuses on controlling fluid or blood loss, replacing lost components, and restoring circulation.

Hypervolemia

  • Definition: Also known as fluid overload, occurs when there is excess water in the body.

  • Common Cause: Kidney problems affecting salt and fluid balance.

  • Treatment Goal: Rid the body of excess fluid.

Intravenous Rehydration

  • Crystalloid Solutions: Small particles that pass easily from the bloodstream into cells and tissues.

  • Categorization by Tonicity:

    • Hypotonic Solutions: Move water from extracellular space into cells.

    • Hypertonic Solutions: Cause water to leave cells.

    • Isotonic Solutions: No movement between extracellular and intracellular fluids.

Blood Transfusions

  • Packed Red Blood Cells (RBCs): Used to restore blood levels without significantly increasing blood volume.

  • Whole Blood: Contains white cells, red cells, and platelets suspended in plasma. Used in significant blood loss scenarios (trauma/surgery).

  • Plasma: Liquid portion of blood where cells are suspended; transports cells.

  • Platelets (Thrombocytes): Prevent bleeding; frequently utilized in organ transplants, cancer treatments, and surgeries.

Intake and Output

  • Intake: Refers to all substances taken in by a client (oral, intravenous, feeding tubes).

  • Output: Refers to the amounts produced by the body (urine, bowel movements, vomiting).

  • Recording Frequency: Should be documented at least every 8 hours or per facility protocol.

Acid-Base Balance

  • Definition: Correct balance of acidic and basic (alkaline) compounds in the blood.

  • Acidosis: Occurs when acid levels are excessively high.

  • Alkalosis: Occurs when blood becomes too alkaline.

Common Causes of Metabolic Acidosis

  • Kidney disease

  • Lactic acidosis

  • Diabetic acidosis (accumulation of ketones when diabetes is uncontrolled)

  • Severe dehydration

  • Severe diarrhea (loss of excessive amounts of sodium bicarbonate)

Common Causes of Metabolic Alkalosis

  • Diuretic overuse

  • Excessive vomiting

  • Ingestion of antacids

  • Rapid loss of potassium or sodium

  • Bicarbonate ingestion

  • Alcohol abuse

  • Use of laxatives

  • Heart, kidney, or liver failure

Respiratory Alkalosis

  • Definition: Occurs when carbon dioxide levels drop too low, often due to rapid or deep breathing (hyperventilation).

Respiratory Acidosis

  • Definition: Occurs when the lungs cannot adequately remove carbon dioxide from the body.

  • Common Causes:

    • Airway diseases (COPD, asthma)

    • Chest and breathing impairment (e.g., scoliosis)

    • Lung tissue diseases

    • Medications that suppress breathing (e.g., narcotics)

    • Severe obesity

    • Obstructive sleep apnea