Makindo Medical Notes

😮‍💨 Hyperventilation Syndrome is often a functional disorder linked to anxiety and panic attacks. ✅ Always exclude organic causes (e.g., asthma, PE, LVF) before diagnosis to avoid unnecessary treatments. 🧠 Education and reassurance are the cornerstones of management.

📖 About Hyperventilation Syndrome

Hyperventilation Syndrome is characterised by increased rate and depth of breathing, leading to excessive loss of carbon dioxide (CO₂). This causes respiratory alkalosis → reduced cerebral blood flow + neuromuscular irritability. It commonly occurs in anxiety, panic, or stressful events, but always consider organic pathology.

• ⚠️ Diagnosis of exclusion – rule out cardiac, pulmonary, or metabolic causes first.
• 🩺 Can coexist with somatisation or panic disorder.

🩺 Clinical Presentation

• Triggers: Stress, panic, receiving bad news.
• Respiratory: Rapid deep breathing, air hunger, sense of “can’t get a deep breath.”
• Neuromuscular:
  • ✋ Perioral & digital paraesthesia.
  • ✊ Carpopedal spasm (due to ↓ ionised calcium).
  • 🦵 Muscle cramps, weakness.
• Autonomic / psychological: Palpitations, sweating, dizziness, sense of impending doom.
• Other: Near-syncope, faintness, visual blurring.

🧾 Differentials to Exclude

• 🌬️ Asthma – wheeze, diurnal variation.
• ❤️ LVF – orthopnoea, basal crackles, abnormal echo/BNP.
• 🫁 Pulmonary embolism – pleuritic chest pain, risk factors, CT-PA or V/Q scan.
• 🦠 Lymphangitis carcinomatosa – progressive breathlessness, CT changes.
• 🌫️ Interstitial lung disease – fine inspiratory crackles, HRCT findings.
• ⚡ Metabolic acidosis – Kussmaul breathing, low HCO₃⁻ on VBG/ABG.
• 💪 Neuromuscular weakness – poor effort on spirometry, weak cough.

🔎 Investigations

• 🧾 History & exam: Key to diagnosis – look for context of stress/anxiety.
• 🫁 CXR / CT chest: Should be normal in hyperventilation.
• 📊 Pulmonary function: Normal FEV₁ / FVC if good effort.
• 🩸 ABG: Respiratory alkalosis (↑pH, ↓pCO₂, normal or slightly ↓HCO₃⁻).
• ❤️ ECG / bloods: To rule out cardiac or metabolic pathology.

💊 Management

• 🧘‍♀️ Reassurance: Calm explanation reduces anxiety-driven hyperventilation.
• 😮‍💨 Breathing retraining: Slow diaphragmatic breathing; pursed-lip breathing. – Paper bag rebreathing is rarely recommended now due to risk of hypoxia, but may help acutely if supervised.
• 🧠 Psychological support: CBT, relaxation training, stress management.
• 💊 Medication:
  • Short-term benzodiazepines may help in severe panic states (use cautiously).
  • SSRIs in underlying anxiety/panic disorder.
• 🏃 Lifestyle: Exercise, sleep hygiene, avoiding caffeine/alcohol excess.

📈 Prognosis

• 🟢 Usually benign and self-limiting once anxiety controlled.
• 🟡 Chronic hyperventilation may persist in panic disorder or somatisation.
• 🔴 Misdiagnosis risks → unnecessary anticoagulation, CT scans, or invasive procedures.

📝 Key Exam Tips

• ABG in panic hyperventilation = low pCO₂, high pH.
• Reproducing symptoms with a voluntary “hyperventilation test” can support diagnosis.
• Never forget to exclude PE, asthma, or LVF in acute breathlessness.

📚 References

• British Thoracic Society. Hyperventilation guidance
• Mayo Clinic – Hyperventilation Syndrome overview
• Leigh RJ, Davies R. Hyperventilation and Anxiety. Front Psychol, 2009.
• APA DSM-5. Functional breathing disorders.