Alkalosis

Definition

Alkalosis is an arterial blood pH above 7.45 caused by loss of acid or accumulation of base. It is classified as respiratory (decreased PaCO2 from hyperventilation) or metabolic (increased HCO3-).

Types and Causes

• Respiratory Alkalosis: Anxiety-induced hyperventilation, high altitude, salicylate toxicity (early), sepsis.
• Metabolic Alkalosis: Prolonged vomiting or gastric suctioning, excessive antacid use, diuretics (loop/thiazide), hypokalemia.

Signs and Symptoms

Dizziness, confusion, paresthesia (circumoral and extremity tingling), tetany, muscle cramps, hyperreflexia, and cardiac arrhythmias. Low ionized calcium contributes to neuromuscular excitability.

Nursing Considerations

For respiratory alkalosis, coach slow breathing and treat anxiety. For metabolic alkalosis, replace fluids and electrolytes (especially potassium and chloride), treat the underlying cause, and discontinue offending medications. Monitor ABGs, electrolytes, and cardiac rhythm.

NCLEX Relevance

Commonly tested in questions about vomiting, NG suctioning, or anxiety. Use the ROME method to interpret: Respiratory Opposite (high pH, low CO2) or Metabolic Equal (high pH, high HCO3).