Quiz 3

·       Know indicators of fluid status

o   Urine Specific Gravity: normal range is 1.005 to 1.030. high= seen in patients with decreased renal perfusions or dehydration or SIADH, lower= dilute urine, diuretic use, increased fluid

o   BUN: normal=8 to 21 mg/dL, >90 is 10 to 31 mg/dL. Dehydration- high. Fluid overload- low or normal

o   Creatinine: normal- 10:1 to 20:1. Dehydration- slightly high or normal. Fluid overload: normal or low

o   BUN Creatine: Dehydration-high >20:1 increased reabsorption of urea in kidneys. Fluid overload: low or normal

·       Dehydration affects

o   Hematocrit level: increased because of less plasma volume to red blood cells.

o   Blood Pressure: decreased, less circulating blood volume heart pumps less effectively which shows low blood pressure. Ex: dizziness, weakness, pale skin, confusion, possible syncope.

§  Increases heart rate to maintain cardiac output and compensate for low blood volume.

·       Signs of Fluid Vol. Overload

o   Edema, weight gain in short time, increased blood pressure, bounding pulses, jugular vein distension (JVD), crackles in lungs, shortness of breath, decreases H&H due to hemodilution

·       Administer Supplemental Potassium

o   Oral route- tablets, liquid, powder

o   IV infusion- ONLY if necessary & must be diluted in fluid

o   NEVER IV push or bolus, undiluted IV potassium

·       Different Ways a body loses fluid

o   Sensible losses- urine, feces, wound drainage

o   Insensible losses- sweating, breathing, skin evaporation

·       Fluid & Electrolyte loss in sweating

o   Water (primary) & electrolytes (sodium, potassium, chloride) excessive sweating leads to dehydration like hyponatremia or hypokalemia

·       Urine Output for an Adult

o   Normal: 0.5-1 ml/kg/hr

o   Daily: 1,500-2,000 ml/day

o   Concerning levels:

§  Oliguria: <400 ml/day- dehydration, kidney dysfunction, or shock

§  Anuria: <50 ml/day- kidney failure or obstruction

·       Age related changes increase risk for fluid & electrolyte imbalances

o   Decreased thirst, reduced kidney function, decreased total body water, less concentrated urine production, polypharmacy, accessing or drinking fluids

·       Hypovolemic Shock

o   Patho: server fluid loss leads to perfusion of organs – decreased cardiac output – tissue hypoxia and organ failure

§  Hemorrhage, server dehydration, burns, vomiting, sweating

o   Clinical Manifestations: tachycardia, hypotension, weak thready pulse, cool clammy skin, decreased urine, thirst

o   Management: rapid fluid resuscitation, blood transfusion, O2 therapy, monitor urine output, identify & treat underlying cause

·       Salt Substitutes

o   Have a high % of potassium, which raises the potassium levels in your blood.

·       Calcium Supplements

o   Prevention of hypocalcemia . Prevents seizures, intake foods that are high in calcium content (milk, orange juice, American cheese, broccoli, kale, egg), may cause life-threating issues

·       Elevated serum potassium getting insulin and dextrose

o   Insulin helps shift potassium from the bloodstream into the cells, muscle and liver cells.

o   Dextrose prevents hypoglycemia

·       Hyponatremia: (sodium less than 135) acute or server hypo serum sodium is less than 120 mEq/L in less than 48 hours. Cerebral edema + high mortality in acute hypo. Neuro- lethargy, headache, confusion, gait disorders, nausea, vomiting.

·       Hypernatremia: (sodium greater than 145) nonspecific neuro signs- irritability, agitation, restlessness, lethargy, coma, and seizures. Serve- hypernatremia, hallucinations, delusions, and disorientation. Dehydration, tachycardia, dry mucous membranes, flushed skin, decreased urine, and hypernatremia

·       Hypo-/hyperchloremia: (less than 97) (greater than 107) irritability, hypotension, tetany, shallow respirations, and hyperexcitability of muscles and nerves. / Fluid volume excess, metabolic acidosis, hypernatremia.

·       Hypo-/hyperkalemia: (<3.5 serum potassium) cardiac, pulmonary, neuromuscular, and Gi symptoms. Weakness, lethargy, hyporeflexia, nausea, abdominal crapping, ECG changes. / general fatigue, muscle cramps, palpitations, paresthesia or weakness. Cardiac electrical conduction system. Potassium >6 = bradycardia, sinus arrest, heart blocks, or ventricular dysrhythmias.

Hypomagnesemia (Low Magnesium - <1.3 mEq/L)

🔹 Causes:

• Chronic alcoholism

• Malnutrition

• GI losses (diarrhea, vomiting)

• Diuretics

• Poor absorption (Crohn’s, Celiac)

🔹 Signs & Symptoms:

• Muscle cramps, tremors

• Hyperreflexia, seizures

• Cardiac arrhythmias (Torsades de Pointes)

• Neuromuscular irritability

• Possible hypocalcemia & hypokalemia association

🔹 Treatment:

• Magnesium replacement (IV MgSO₄ for severe cases)

• Increase dietary intake (nuts, green leafy veggies, whole grains)

2. Hypermagnesemia (High Magnesium - >2.1 mEq/L)

🔹 Causes:

• Renal failure

• Excess magnesium intake (antacids, laxatives)

• Adrenal insufficiency

🔹 Signs & Symptoms:

• Hyporeflexia, muscle weakness

• Hypotension, bradycardia

• Respiratory depression

• Prolonged PR interval, widened QRS

🔹 Treatment:

• Stop Mg intake

• IV calcium gluconate (Mg antagonist)

• Loop diuretics + fluids (if kidneys function)

• Dialysis for severe cases

3. Hypocalcemia (Low Calcium - <8.5 mg/dL)

🔹 Causes:

• Hypoparathyroidism

• Vitamin D deficiency

• Renal disease

• Acute pancreatitis

• Blood transfusions (citrate binds calcium)

🔹 Signs & Symptoms:

• Neuromuscular excitability:

  • Trousseau’s sign: Carpal spasm with BP cuff inflation

  • Chvostek’s sign: Facial twitching when tapping cheek

• Tetany, muscle cramps

• Seizures, paresthesia

• Prolonged QT interval (risk of arrhythmia)

🔹 Treatment:

• IV calcium gluconate for severe cases

• Oral calcium & vitamin D for mild cases

• Monitor cardiac status

4. Hypercalcemia (High Calcium - >10.5 mg/dL)

🔹 Causes:

• Hyperparathyroidism

• Malignancy (bone metastases)

• Prolonged immobilization

• Thiazide diuretics

• Excess vitamin D intake

🔹 Signs & Symptoms:

• Muscle weakness, fatigue

• Decreased reflexes

• Kidney stones

• Shortened QT interval → risk of cardiac arrest

• Polyuria, dehydration

🔹 Treatment:

• IV fluids + loop diuretics

• Bisphosphonates (if cancer-related)

• Calcitonin for acute management

Arterial Blood Gas (ABG) Interpretation

Why Would an ABG Be Ordered?

• To assess acid-base balance, oxygenation, and ventilation status.

• Common reasons:

  • Respiratory distress (COPD, pneumonia, ARDS, PE)

  • Metabolic disorders (DKA, kidney failure, sepsis)

  • Acid-base imbalances (shock, overdose, electrolyte imbalances)

ABG Interpretation: Normal Ranges

Acid-Base Disorders

Compensation in ABGs