From the Guidelines
Respiratory alkalosis is primarily caused by hyperventilation, which can be triggered by various factors including anxiety, panic attacks, high fever, high altitude exposure, pain, and certain medications. This condition occurs when the respiratory rate increases beyond what is needed for normal gas exchange, resulting in decreased carbon dioxide levels in the blood and a subsequent rise in blood pH.
Common Causes of Respiratory Alkalosis
- Anxiety or panic attacks, which trigger rapid breathing 1
- High fever, which increases metabolic rate and respiratory drive
- High altitude exposure, where the body compensates for lower oxygen levels by breathing faster
- Pain, which can stimulate hyperventilation
- Certain medications like salicylates, progesterone, and nicotine that stimulate the respiratory center
- Central nervous system disorders such as meningitis or encephalitis
- Pregnancy, due to hormonal changes that increase respiratory drive
- Liver disease
- Mechanical ventilation when set at rates that exceed metabolic needs
- Sepsis can also cause respiratory alkalosis in its early stages as inflammatory mediators stimulate breathing 1 Understanding these causes is important for proper diagnosis and management, as treatment typically focuses on addressing the underlying condition rather than the alkalosis itself.
Key Considerations
- Respiratory alkalosis can be a compensatory mechanism in certain conditions, such as heart failure with reduced ejection fraction 1
- Treatment of the underlying condition is crucial in managing respiratory alkalosis
- Identifying the underlying cause of hyperventilation is essential for proper management and treatment of respiratory alkalosis 1
From the Research
Causes of Respiratory Alkalosis
Respiratory alkalosis is a condition that occurs when the lungs remove too much carbon dioxide from the bloodstream, causing the blood to become alkaline. The causes of respiratory alkalosis can be divided into several categories:
- Pulmonary disorders: Such as pneumonia, asthma, or chronic obstructive pulmonary disease (COPD) 2
- Extrapulmonary disorders: Such as hyperventilation syndrome, which can be caused by anxiety, panic attacks, or other psychological factors 3
- Salicylate intoxication: High levels of salicylate, such as those found in aspirin overdose, can cause respiratory alkalosis by stimulating the respiratory center in the brain 4
- Other causes: Such as severe pain, fever, or sepsis, which can also lead to hyperventilation and respiratory alkalosis 2
- Psychogenic hyperventilation: A condition in which a person hyperventilates due to psychological factors, such as anxiety or stress, leading to respiratory alkalosis 5
Key Factors Contributing to Respiratory Alkalosis
Several key factors contribute to the development of respiratory alkalosis, including:
- Hyperventilation: Breathing more rapidly or deeply than normal, which can lead to an excessive removal of carbon dioxide from the bloodstream 3
- Low PaCO2: A decrease in the partial pressure of carbon dioxide in the arterial blood, which can lead to an increase in blood pH 6
- Increased sympathetic adrenergic tone: An increase in the activity of the sympathetic nervous system, which can lead to hyperventilation and respiratory alkalosis 3