Hyperventilation that does not resolve, or with hypoxia - look for a serious cause (PE, sepsis, salicylate overdose) and notify provider.
Before you read
Test yourself first: 5 questions
Question 1 of 5
A client with respiratory alkalosis from anxiety-induced hyperventilation reports numbness and tingling of the fingers and around the mouth. The nurse explains these symptoms result from which mechanism?
Answer: A. Alkalosis increases the binding of calcium to albumin, lowering the ionized calcium level. This relative hypocalcemia causes the paresthesias, perioral numbness, and carpopedal spasm seen in respiratory alkalosis. The total calcium is unchanged, but the active ionized fraction falls.
Question 2 of 5
A client receiving mechanical ventilation has the rate set too high and develops pH 7.50, PaCO2 28 mmHg, HCO3 24 mEq/L. Which action should the nurse anticipate?
Answer: A. These values show respiratory alkalosis from iatrogenic overventilation. Lowering the ventilator respiratory rate (or tidal volume) allows CO2 to rise back toward normal and corrects the alkalosis. Adding bicarbonate or increasing the rate would worsen the alkalosis.
Question 3 of 5
A client hyperventilating from anxiety has an ABG of pH 7.52, PaCO2 28 mm Hg, HCO3 24 mEq/L. What is the priority nursing action?
Answer: B. These values show respiratory alkalosis from blowing off CO2. Coaching the client to slow and control breathing reduces CO2 loss and corrects the imbalance. Oxygen and bicarbonate are not indicated.
Question 4 of 5
An ABG shows pH 7.50, PaCO2 30 mmHg, HCO3 24 mEq/L. Which condition most likely caused this result?
Answer: A. An elevated pH with a low PaCO2 and normal bicarbonate indicates respiratory alkalosis, commonly caused by hyperventilation from anxiety, pain, or fever blowing off too much carbon dioxide.
Question 5 of 5
An anxious client is hyperventilating in the emergency department. Which arterial blood gas results does the nurse expect to find?
Answer: A. Hyperventilation blows off carbon dioxide, lowering the PaCO2 and raising the pH, which produces respiratory alkalosis. The expected pattern is an elevated pH with a decreased PaCO2 and an initially normal bicarbonate before any renal compensation occurs.
Keep the streak going with more questions like these, each with a full rationale.
What is respiratory alkalosis?
Common causes include anxiety/panic, pain, fever, hypoxia, salicylate (aspirin) overdose, and over-aggressive mechanical ventilation. Because CO2 is an acid, blowing off too much CO2 raises pH. Anxiety-driven hyperventilation is the classic and most common cause.
Key points to remember
- ABG pattern: high pH (over 7.45) with low PaCO2 (under 35 mmHg); the low CO2 drives the disorder.
- Hyperventilation is the cause, so the client breathes rapidly and deeply.
- Increased neuromuscular excitability causes tingling/numbness of fingers, toes, and around the mouth, plus muscle cramps and spasms.
- Lightheadedness, dizziness, and a feeling of panic or chest tightness are common.
- Severe alkalosis can cause carpopedal spasm, tetany, and seizures.
- It is usually acute; renal compensation (excreting bicarbonate) takes hours to days and is limited.
Common causes
- Anxiety, panic, fear
- Fever, pain, PE, high altitude
Signs & symptoms
- Lightheaded, tingling fingers
- Tetany, dizzy, palpitations
Nursing priorities
- Help the client slow and control their breathing using calm coaching and reassurance.
- Identify and treat the underlying cause (relieve anxiety, treat pain, fever, hypoxia, or salicylate toxicity).
- For anxiety-driven hyperventilation, encourage slow breathing or breathing into cupped hands/paper bag if appropriate to rebreathe CO2.
- Monitor ABGs, oxygen saturation, and for tetany or paresthesias.
- Provide oxygen and address hypoxia if that is the trigger for hyperventilation.
Labs & values
Patient teaching
- Practice slow, controlled breathing and relaxation techniques for anxiety.
- Recognize early signs of hyperventilation, such as tingling and dizziness.
- Seek care for sudden shortness of breath, chest pain, or breathing fast with no clear cause.
Red flags: report now
- Hyperventilation that does not resolve, or with hypoxia - look for a serious cause (PE, sepsis, salicylate overdose) and notify provider.
- Tetany, carpopedal spasm, or seizures - report immediately.
- In a salicylate overdose, respiratory alkalosis may progress to mixed acid-base disturbance - escalate.
References
Clinical references for this topic
