Etiology and Clinical Manifestations of Respiratory Alkalosis

Introduction

Respiratory alkalosis is a condition characterized by a primary reduction in arterial carbon dioxide tension (PaCO₂), leading to an increase in blood pH. It is one of the four primary types of acid-base imbalances in human physiology and results primarily from hyperventilation.

Etiology of Respiratory Alkalosis

Primary Causes

• Acute hyperventilation due to anxiety or panic attacks
• Fever and pain
• Use of certain drugs (e.g., salicylates)

Secondary Causes: Physiological and Pathological Triggers

Physiological Triggers

• High Altitude: Low oxygen levels stimulate hyperventilation through peripheral chemoreceptors.
• Pregnancy: Increased progesterone levels stimulate the respiratory center, leading to mild hyperventilation.
• Exercise: Temporary respiratory alkalosis can occur due to rapid breathing during intense physical activity.

Pathological Triggers

• Sepsis: Cytokine-mediated stimulation of the respiratory center causes increased ventilation.
• Liver Failure: Leads to altered central control of breathing.
• Head Trauma or Stroke: Disruption in brainstem regulation of respiration.

Clinical Manifestations

Signs and symptoms of respiratory alkalosis vary depending on its severity and underlying cause, but may include:

• Lightheadedness or dizziness
• Paresthesias (numbness and tingling)
• Muscle cramps or spasms
• Palpitations
• Tetany or seizures in severe cases

Conclusion

Respiratory alkalosis is most often a transient response to a physiological or psychological trigger but can also signify underlying pathology. Identifying the cause is key to appropriate treatment. Understanding its etiology and clinical features assists clinicians in timely diagnosis and management.