Chronic Illness and Fluid Imbalances

Fluid and Electrolyte Balance

• Antidiuretic hormone (AVP) production increases renal water excretion.
• Imbalances often linked to renal failure, cardiac failure (fluid retention), liver failure (ascites), respiratory failure, and chemotherapy.

Factors Influencing Balance

• Key conditions affecting fluid, electrolyte, and acid-base balance include:
  • Renal failure (filtering issues)
  • Cardiac failure (pump issues)
  • Liver failure
  • Respiratory failure
  • Surgery and pregnancy

Fluid Imbalance Types

• Extracellular fluid volume imbalance:
  • Deficit
  • Excess
• Water or osmolality imbalance:
  • Deficit or hyperosmolality
  • Excess or hyposmolality

Acid-Base Imbalance Types

• Respiratory acidosis
• Metabolic acidosis
• Respiratory alkalosis
• Metabolic alkalosis

Manifestations of Imbalances

• Imbalance in intake/output and body weight.
• Changes in mental status and vital signs (respiratory rate, heart rate, blood pressure).
• Abnormal tissue hydration and muscle tone.

Life Span Considerations

• Very young and very old individuals are at higher risk for fluid and electrolyte imbalances.

Newborn and Infant Considerations

• Newborns have a body water percentage of 70-80%, making dehydration more likely.

Pressures Affecting Fluid Movement

• Osmotic pressure keeps fluid within blood vessels.
• Hydrostatic pressure aids fluid filtration from high-pressure areas to low-pressure zones.
• Filtration pressure is the difference between hydrostatic and osmotic pressures.

Mechanisms of Fluid Volume Regulation

• Fluid intake and output regulation through:
  • Thirst response
  • Kidney function
  • Renin-angiotensin-aldosterone system
  • Atrial natriuretic peptide (ANP)

Fluid Volume Deficits

• Hypovolemia refers to decreased blood volume due to fluid loss, reduced intake, or fluid shift.
• Causes: Hemorrhage, vomiting, diarrhea, fever, burns.
• Symptoms: Hypotension, tachycardia, dry mucous membranes, decreased urine output.

Fluid Volume Excess

• Hypervolemia is excess fluid volume, potentially due to conditions like alcohol use or renal failure.
• Complications may include apnea, muscle fatigue, and EKG changes.

Key Electrolytes

• Calcium:

  • Crucial for neuromuscular function, blood clotting, and bone health.
  • Normal serum range: 8.2-10.5 mEq/L.
  • Low levels (hypocalcemia) can result from hypoparathyroidism or vitamin D deficiency.

• Phosphorus:

  • Major intracellular anion involved in bone health and metabolism.
  • Normal range: 2.5-4.5 mg/dL.
  • Decreases (hypophosphatemia) may arise from alkalosis; increases (hyperphosphatemia) associated with renal failure.

• Magnesium:

  • Major intracellular cation vital for muscle and nerve function.
  • Normal range: 1.5-2.5 mg/dL.
  • Low levels (hypomagnesemia) can result from malnutrition; high levels (hypermagnesemia) from renal failure.

• Chloride:

  • Major extracellular anion crucial for acid-base balance.
  • Normal serum range: 95-105 mEq/L.
  • Low (hypochloremia) often due to excessive vomiting; high (hyperchloremia) due to increased ingestion or decreased excretion.

Acid-Base Balance Overview

• Regulation through buffering and compensation mechanisms (respiratory and renal).

Assessment Criteria

• Assess history of fluid, electrolyte, or acid-base issues.
• Monitor dietary habits and fluid intake/output patterns.
• Physical assessment includes vital signs, body weight, and integumentary examination.

Daily Weighing Protocol

• Weigh patients daily at the same time, preferably in the morning, for accuracy.
• Consistent clothing and scales improve reliability.

Integumentary Assessment

• Skin turgor and membrane condition offer insights into hydration status.

This quiz covers the impact of chronic illnesses such as renal, cardiac, liver, and respiratory failures on fluid imbalances in the body. Learn how these conditions affect renal excretion and overall fluid regulation, including the effects of treatments like chemotherapy. Test your understanding of these critical concepts in managing chronic health issues.