From the Guidelines
Primary respiratory alkalosis is primarily caused by hyperventilation, which can be triggered by various factors, including anxiety, stress, and high altitude exposure.
Causes of Primary Respiratory Alkalosis
- Hyperventilation syndrome: characterized by abnormal breathing patterns, including rapid and shallow breathing, often associated with anxiety, stress, and psychogenic disorders 1
- High altitude exposure: triggers physiological acclimatization processes, including an increase in respiratory rate and tidal volume, leading to respiratory alkalosis 1
- Centrally mediated hyperventilation: occurs in early sepsis, resulting in respiratory alkalosis 1 These causes of primary respiratory alkalosis can lead to a decrease in PaCO2 levels, resulting in respiratory alkalosis. It is essential to identify and address the underlying cause of hyperventilation to provide appropriate treatment. In some cases, such as hyperventilation syndrome, treatment can be successful with proper management 1.
From the Research
Causes of Primary Respiratory Alkalosis
- Respiratory alkalosis occurs when alveolar ventilation exceeds that required to eliminate the carbon dioxide produced by tissues 2
- Disorders that increase alveolar ventilation are the most common cause of respiratory alkalosis, defined by an arterial partial pressure of CO2 <35 mm Hg with subsequent alkalization of body fluids 3
- Dysfunction of the respiratory system's control center can lead to respiratory alkalosis 4
- Hyperventilation syndrome is a common etiology of respiratory alkalosis in the emergency department setting and is a diagnosis by exclusion 5
- Pulmonary or extrapulmonary disorders can also be etiologies of respiratory alkalosis 5
Key Characteristics
- Concurrent decreases in Paco2, increases in pH, and compensatory decreases in blood HCO3- levels are associated with respiratory alkalosis 2
- Acute or chronic respiratory alkalosis can occur, with metabolic compensation initially consisting of cellular uptake of HCO3- and buffering by intracellular phosphates and proteins 2
- Chronic respiratory alkalosis results in longer-lasting decreases in renal reabsorption of HCO3-; the arterial pH can approach near-normal values 2