A drop in systolic blood pressure (SBP) >10 mmHg during inspiration.
- Normal: BP falls slightly during inspiration.
- In PP: BP drops excessively, causing weak pulse or no pulse on inspiration.
CAUSES OF PULSUS
PARADOXUS
• Cardiac Causes (↓ Heart Filling)
- Cardiac Tamponade
(Fluid around heart compresses it)
- Pericarditis
(Inflamed pericardium restricts heart expansion)
- Restrictive Cardiomyopathy
• Respiratory Causes (↑ Lung Pressure)
- Severe Asthma, COPD
- Tension Pneumothorax
(Collapsed lung increases chest pressure)
- Pulmonary Embolism (PE)
Mnemonic:
"TAP-P (Causes of PP)
- Tamponade
- Asthma
- Pneumothorax
- Pulmonary
Embolism
MECHANISM OF
PULSUS PARADOXUS
1. Normal Breathing:
- Inspiration
→ Lungs expand, chest pressure drops,
more blood returns to heart.
- Slight BP drop (Normal: <10 mmHg).
2. In Cardiac Tamponade & Lung Disease:
- Heart
cannot expand fully due to fluid or lung pressure.
- Less blood reaches the heart → Less
blood pumped → BP drops more (>10 mmHg).
Mnemonic:
"Big Inspiration, Small Circulation"
- Big Inspiration
= Lungs expand too much
- Small Circulation
= Less blood pumped
SIGNS &
SYMPTOMS
- Weak pulse or no pulse during inspiration
- Low BP, breathlessness
- Beck’s Triad (for Tamponade):
- Low BP
- Raised JVP
- Muffled Heart Sounds
DIAGNOSIS OF
PULSUS PARADOXUS
- Blood Pressure Measurement (Sphygmomanometer) → Difference in BP >10 mmHg during breathing
- ECG → Low voltage QRS (if tamponade)
- Echocardiography (ECHO) → Shows fluid around heart (Tamponade)
Mnemonic:
"BP-ECG-ECHO" (Tests for PP)
- BP Drop (>10 mmHg)
- ECG (Low voltage in Tamponade)
- ECHO (Fluid in Pericardium)
TREATMENT OF
PULSUS PARADOXUS
- For Cardiac Tamponade → Pericardiocentesis (Remove fluid around heart)
- For Asthma, COPD → Oxygen, Bronchodilators (Salbutamol, Steroids)
- For Pneumothorax → Needle Decompression, Chest Tube
Mnemonic:
"FAN" (Fix the Cause of PP)
- Fluid Drain
(Pericardiocentesis for Tamponade)
- Airway Open
(Asthma, COPD treatment)
- Needle
Decompression (Pneumothorax)
FINAL REVISION WITH MNEMONICS
- Causes = "TAP-P" (Tamponade, Asthma, Pneumothorax, Pulmonary Embolism)
- Mechanism = "Big Inspiration, Small Circulation"
- Diagnosis = "BP-ECG-ECHO"
- Treatment = "FAN" (Fluid Drain, Airway Open, Needle Decompression)
