Fluids & Electrolytes Quick

Introduction to Fluid and Electrolytes

• Fluid and electrolytes are essential for understanding disease processes and treatments in clinical practice.

• Knowledge of the basics is foundational for administering medications and managing patients.

Types of IV Fluids

Crystalloids

• Clear intravenous (IV) fluids that can include isotonic, hypotonic, and hypertonic solutions.

• Common examples: 0.9% Normal Saline and Lactated Ringer's Solution (isotonic), Half Normal Saline (hypotonic), and 3% Saline (hypertonic).

Colloids

• More viscous solutions like albumin and blood products, used for specific indications.

Isotonic Solutions

• Examples include 0.9% Normal Saline and Lactated Ringer's.

• Function: Do not cause fluid movement between intracellular fluid (ICF) and extracellular fluid (ECF).

• Indication: Great for volume replacement in patients.

Hypotonic Solutions

• Example: Half Normal Saline.

• Function: Moves fluid from ECF into the intracellular space, leading to cellular hydration.

• Indication: Used for hydration purposes, especially in cases of cellular dehydration.

Hypertonic Solutions

• Example: 3% Saline.

• Function: Pulls water out of cells into the extracellular space.

• Indication: Useful in treating severe hyponatremia and cerebral edema.

Key Electrolytes to Know

Sodium (Na+)

• Normal range: 135-145 milliequivalents per liter.

• Symptoms of Abnormal Levels:

  • Hypernatremia: Thirst, dry mucous membranes, neurological changes (confusion, seizures).

  • Hyponatremia: Similar neurologic manifestations; both require monitoring for symptoms.

  • Note: Sodium levels strongly correlate with neurological status.

Potassium (K+)

• Normal range: 3.5-5.0 milliequivalents per liter.

• Symptoms of Abnormal Levels:

  • Hypokalemia: Fatigue, muscle weakness; can require supplemental potassium.

  • Hyperkalemia: May lead to cardiac arrhythmias; requires rapid intervention through dialysis or medications (KX Fleet).

  • Note: Potassium should NEVER be crushed or pushed in IV form due to life-threatening risks.

Calcium (Ca2+)

• Normal range: 8.8-10.4 milligrams per deciliter.

• Symptoms of Abnormal Levels:

  • Hypocalcemia: Results in Trousseau's and Chvostek's signs with risk of tetany, seizures, cardiac arrhythmias.

  • Hypercalcemia: Leads to decreased reflexes, potential fractures, and arrhythmias.

Phosphorus (P)

• Normal range: 2.7-4.5 milligrams per deciliter.

• Relationship with Calcium: Inverse relationship; when calcium levels are abnormal, phosphorus levels are often affected.

Magnesium (Mg2+)

• Normal range: 1.8-2.6 milligrams per deciliter.

• Symptoms of Abnormal Levels:

  • Hypomagnesemia: Neurological manifestations.

  • Hypermagnesemia: Depressed reflexes and possible Torsades de Pointes; life-threatening arrhythmia.

Conclusion

• Awareness of fluid and electrolyte imbalances is crucial for patient safety and effective treatments.

• Memorization of these values and associated symptoms is vital for clinical practice.

Chloride (Cl-)

• Normal Range: 98-106 milliequivalents per liter.

• Functions: Plays a crucial role in maintaining acid-base balance, osmolality, and fluid balance in the body. Often found in conjunction with sodium.

• Symptoms of Abnormal Levels:

  • Hypochloremia: May lead to metabolic alkalosis and symptoms such as muscle spasms or twitching.

  • Hyperchloremia: Can result in metabolic acidosis, potentially causing confusion, fatigue, or irritability.

• Importance: Requires monitoring in patients with conditions affecting fluid balance or renal function, as abnormalities can have significant clinical implications.

Phosphorus (P)

• Normal Range: 2.7-4.5 milligrams per deciliter.

• Functions: Essential for the formation of bones and teeth, energy production (ATP), and cellular function. Plays a crucial role in acid-base balance and is involved in nucleic acid synthesis.

• Relationship with Calcium: Inverse relationship; abnormal calcium levels often affect phosphorus levels. Elevated calcium can decrease phosphorus and vice versa.

• Symptoms of Abnormal Levels:

  • Hypophosphatemia: May lead to bone pain, weakness, and increased risk of fractures.

  • Hyperphosphatemia: Often seen in renal failure; can cause itching, soft tissue calcification, and cardiovascular issues.

• Importance: Monitoring phosphorus levels is significant in patients with kidney disease, metabolic bone disease, and those receiving phosphate-binding medications.

Magnesium (Mg2+)

• Normal Range: 1.8-2.6 milligrams per deciliter.

• Functions: Critical for over 300 biochemical reactions in the body, including energy production, protein synthesis, and DNA/RNA synthesis. Important for muscle and nerve function, blood glucose control, and blood pressure regulation.

• Symptoms of Abnormal Levels:

  • Hypomagnesemia: Characterized by neurological manifestations such as tremors, seizures, muscle spasms, and increased heart rate.

  • Hypermagnesemia: Leads to depressed reflexes, potential hypotension, nausea, vomiting, and can progress to severe complications like Torsades de Pointes, a life-threatening arrhythmia.

• Importance: Monitoring magnesium levels is essential, especially in patients with chronic illnesses, renal dysfunction, or those receiving medications that may affect magnesium metabolism.