Since the primary cause of all respiratory alkalosis etiologies is hyperventilation, many patients present with complain to shortness of breath. The exact history and physical exam findings are highly variable as there are many pathologies that induce the pH disturbance. These may include acute onset dyspnea, fever, chills, peripheral edema, orthopnea, weakness, confusion, light-headedness, dizziness, anxiety, chest pain, wheezing, hemoptysis, trauma, history of central line catheter, recent surgery, history of thromboembolic disease, history of asthma, history of COPD, acute focal neurological signs, numbness, paresthesia, abdominal pain, nausea, vomiting, tinnitus, or weight loss.

Physical exam findings may be just as varied depending on etiology to include fever, tachycardia, tachypnea, diaphoresis, hyper or hypotension, altered mental status, productive or non-productive cough, wheezing, rales, crackles, cardiac murmur or arrhythmia, jugular venous distension, meningeal signs, focal neurological loss, Trousseau sign, Chvostek sign, jaundice, melena, hematochezia, hepatosplenomegaly, or there may be no definitive signs at all.[10][11]

With a wide preliminary differential diagnosis list, evaluation should always begin with a thorough history and physical exam to focus diagnostic considerations. In all cases, arterial blood gas is necessary to diagnose the pH imbalance. Serum electrolytes should be measured with particular attention to sodium, potassium, and calcium levels as aberrations in these may lead to further complication. Magnesium and phosphate are also essential to measure. In hypoxic patients, it is important to calculate the A-a gradient to determine the etiology and further diagnosis. If the A-a gradient is wide, be suspicious of pulmonary embolism and appropriately work up the patient. A chest x-ray is important in all patients as it helps discern an anatomical or infectious cause and may rule in/out pulmonary edema. If there is a clinical reason for it, chest CT can play a vital role in achieving a diagnosis. If there is appropriate clinical suspicion for neurological insult, CT or MRI of the head may be appropriate along with lumbar puncture for WBC, glucose, and protein analysis.[1][12][13]

Treatment of metabolic alkalosis is targeted at treating the underlying pathology. In anxious patients, anxiolytics may be necessary. In infectious disease, antibiotics targeting sputum or blood cultures are appropriate. In embolic disease, anticoagulation is necessary. Ventilator support may be necessary for patients with acute respiratory failure, acute asthma, or acute, chronic obstructive pulmonary disease (COPD) exacerbation if they show signs of respiratory fatigue. In ventilator controlled patients, it may be necessary to reevaluate their ventilator settings to reduce respiratory rate. If hyperventilation is intentional, monitor the arterial or venous blood gas values closely. In severe cases, pH may be directly reduced using acidic agents. However, this is not routinely done.[14][15][16]

Other possibilities include:

• Asthma exacerbation
• Atrial fibrillation
• Atrial flutter
• Atrial tachycardia
• Bacterial pneumonia
• Bacterial sepsis
• Community-acquired pneumonia
• COPD exacerbation
• Head trauma
• Heatstroke
• Hyperthyroidism and thyrotoxicosis
• Idiopathic pulmonary fibrosis
• Meningitis
• Metabolic acidosis
• Metabolic alkalosis
• Myocardial infarction
• Panic disorder
• Pneumothorax
• Pulmonary edema
• Pulmonary embolism
• Salicylate toxicity
• Theophylline toxicity
• Viral pneumonia

Respiratory alkalosis in itself is not a life-threatening diagnosis. However, the prognosis is variable depending on etiology.

Respiratory alkalosis is a pathology that is secondary to hyperventilation.

Hyperventilation typically occurs in response to an insult such as hypoxia, metabolic acidosis, pain, anxiety, or increased metabolic demand.

Respiratory alkalosis in itself is not life-threatening; however, the underlying etiology may be. Always look for and treat the source of the illness. Interventions to reduce pH directly are typically not necessary as there is no mortality benefit to this therapy.

Respiratory alkalosis is easy to diagnose but its management can be difficult; the key is to find the cause. Because there are many causes of respiratory alkalosis, the condition is best managed by an interprofessional team that includes an internist, primary care provider, nurse practitioner, pulmonologist, mental health nurse and a pain specialist.

Treatment of metabolic alkalosis is targeted at treating the underlying pathology. If hyperventilation is intentional, monitor the arterial or venous blood gas values closely. In severe cases, pH may be directly reduced using acidic agents. However, this is not routinely done. Hyperventilation typically occurs in response to an insult such as hypoxia, metabolic acidosis, pain, anxiety, or increased metabolic demand.

Respiratory alkalosis in itself is not life-threatening; however, the underlying etiology may be. Always look for and treat the source of the illness. Interventions to reduce pH directly are typically not necessary as there is no mortality benefit to this therapy.