[Percutaneous pleural and pericardial drainage]

Both MRI, CT and sonography will give a good presentation of fluid collection in pleura and pericardium. Sonography is the ideal imaging method for monitoring interventional procedures. Its ability to visualize superficial fluid collection and its real-time capability allows precise control of needle and catheter insertions. If the abnormality is poorly seen with ultrasound, often because of air in the collection, CT can be used as a guidance system. Diagnostic thoracocentesis and pericardiocentesis are performed mainly to exclude malignancy and infections, and the punctions are made with small needles. Therapeutic thoracocentesis is usually performed to relieve dyspnoea and small catheters are used. Drainage of empyema is performed with larger catheters because of the high viscosity of the infected fluid. Patients with threatening cardiac tamponade will often respond immediately to drainage of the pericardial space by catheter. These procedures can be done with local anesthesia only. If complications occur, it is mainly the pneumothorax that has to be treated. This can be managed directly under the procedure as the drainage catheter is attached to continuous pleural suction, or a catheter can be inserted in the pleural space after diagnostic punction. Patients with coagulation abnormalities must be evaluated especially before any intervention, otherwise there are no contraindications for these image-guided percutaneous procedures.