Respiratory Alkalosis Causes and Mechanisms

Pathophysiological Mechanisms and Common Causes

Anxiety reactions, panic disorders, and hyperventilation syndrome are common causes of respiratory alkalosis, characterized by abnormal breathing patterns with impressive hyperventilation, increased respiratory frequency, and respiratory alkalosis (decreased PaCO2) 1
Physiological hyperventilation occurs as a compensatory mechanism in various conditions, including heart failure with Cheyne-Stokes breathing, creating respiratory alkalosis that may protect the failing heart from decompensation 2, 3, 4
Compensatory response to metabolic acidosis to maintain pH near normal, according to the American Thoracic Society 5

Hypoxemia stimulates peripheral chemoreceptors, leading to increased ventilation, and pulmonary disorders that stimulate ventilation include pneumonia, pulmonary embolism, and pulmonary edema 3, 4, 6
Stimulation of the respiratory center in the medulla can cause hyperventilation, and common CNS causes include head injury, cerebrovascular accidents, and central nervous system infections 2, 4, 6

Mechanical ventilation with excessive settings and inappropriate ventilator management in critical care settings can cause respiratory alkalosis 3, 7
In metabolic disorders with compensatory respiratory alkalosis, avoid disrupting the compensatory mechanism, and if assisted ventilation is necessary, target appropriate oxygen saturation (88-92%) to avoid worsening the condition, as recommended by the American College of Chest Physicians 5
Avoid excessive oxygen therapy that could disrupt compensatory mechanisms in patients with chronic respiratory alkalosis, according to the European Respiratory Society 5, 6

Panic disorder commonly presents with clustering of suffocating, smothering, and air hunger sensations, and may occur even in the absence of reduced ventilatory capacity due to excessive ventilatory drive or increased sensitivity to CO2, as noted by the American Journal of Respiratory and Critical Care Medicine 8

Respiratory dyskinesia from antipsychotic medications can lead to respiratory alkalosis, often undiagnosed, and includes orofacial dyskinesia, dysphonia, and dyspnea, according to Pediatrics 9