Thoracentesis - pleural effusion for students

Thoracentesis is a minimally invasive procedure that doctors use to diagnose and treat pleural effusions. This is a condition in which there is excess fluid in the pleural space, also called the pleural cavity. This space exists between the outside of the lungs and the inside of the chest wall.

1. Dr. Thomas Hess Dept. of Respiratory Medicine Kantonsspital Graubünden Kantonsspital Baden Switzerland [email protected] Pleural effusion Thoracentesis

2. Physiology pleural fluid

3. Ultrastructure of pleura communication pleura - lymphatics S L = lacuna S = Stoma

4. Pleura effusion definition - pathophysiology Definition: > 10 – 20 ml (physiological amount) fluid in the pleural space Pathophysiology: Accumulation of fluid in the pleural space, if there is Production > drainage capacity of parietal pleura example: cardiac effusion Obstruction of lymphatic outflow in the parietal pleura example: carcinomatous pleurisy Both (most frequent)

5. Clinical signs Dyspnoea Ev. c hest pain pleural empyema, parapneumonic effusion, pulmonary embolism, pleural mesothelioma … No chest pain: cardiac effusion, hydrothorax in liver disease... Dullness on percussion (if > 300 – 400 ml) Decreased breath sound

6. Methods of imaging of pleural effusion Thorax Rx (pa and lateral) Chest CT (with contrast media) Transthoracic ultrasound Investigation in sitting position (as for thoracentesis)

7. l ateral a scending line Large left sided pleural effusion

8. Medium sized left / small right sided effusion

9. Lateral view – bilateral small – medium sized PE

10. Small right sided subpleural effusion

11. Large left sided PE / tension hydrothorax

12. h orizontal line a ir-liquid level pneumothorax Seropneumothorax

13. Pleural effusion vs. atelectasis

14. Pleural Empyema

15. Rule: every pleural effusion should be punctured for diagnostic reasons Except: Cardiac effusion (with high reliability) Known heart disease Bilateral PE right > left or small-medium right PE Parapneumonic PE and clinical response to antibiotic treatment Known liver disease with ascites and pleural effusion without fever Small pleural effusions (< 300 – 400 ml)

16. Exudate vs. Transudates Light criteria for exudates Combined Light’s criterion: high sensitivity / low specificity = we don’t miss any exudate, but misclassify some transudates Effusion concentration Effusion/serum ratio Sensitivity % Accuracy % Total protein LDH > 30 g/L >200 U/L** > 0.5 > 0.6 89.5 91.4 95.4 94.7 ** or: > 2/3 of upper limit of serum LDH If one criterion is positive = exudate !

17. Further pleural fluid parameters (as needed) Exudate vs. Transudate Cholesterol > 45 mg/dl (1.15 mmol/l) Chylothorax Triglyceride > 110 mg/dl (1.25 mmol/l) confirmed 50 – 110 mg/dl (0.55 – 1.25 mmol/l) possible < 50 mmol/dl (0.55 mmol/l) excluded Amylase Pancreatitis, oesophagus rupture, malignancy Haematocrit > 0.5 Blood = Haematothorax

18. pH - measurement Aspirate with blood gas syringe (without air) Immediately (< 10 min) measure pH with a blood gas analyser If very purulent: don’t measure (risk of occlusion of blood gas machine) Interpretation Parapneumonic effusion: < 7.20 = complicated parapneumonic effusion / empyema -> need for drainage > 7.20 = uncomplicated parapneumonic effusion -> no drainage needed

19. Causes of pleural transudates

20. Causes of pleural exudates

21. Avoid this zone for puncture: oblique i ntercostal artery ev. between the ribs Thoracentesis – technique (1)

22. Thoracentesis – technique (2) diagnostic puncture Mark planned puncture site (if possible with ultrasound) at the upper rim of a rib Disinfect the selected region (povidone-iodine or alcohol). Tap a sterile draping to the pat. Local anaesthesia (e.g. Lidocain 1%) is injected from skin (small depot) over the muscle to the rib, advance the needle over the rib under suction, if you can aspirate fluid withdraw the needle slowly until aspiration stops (subpleural position) and inject a good depot Puncture with a new syringe (50 ml) and preferentially 18G needle and aspirate 50 ml (if possible) Always advance the needle under suction !

23. Thoracentesis – technique (2 ) detail

24. Thoracentesis – technique (3) therapeutic puncture Instead of a 18 G needle puncture with a over the needle i.v. catheter and a syringe, if you can aspirate fluid advance the catheter over the needle and introduce the full length, withdraw the needle Close the catheter with the thumb of your left hand (air entry!) Connect a (prepared) short connection tube with a three-way stopcock a syringe (50 ml and a fluid collection bag Aspirate fluid with the syringe, turn the stopcock and fill the tube to the bag, turn back and aspirate an other syringe for diagnostic investigation, turn the stopcock back and remove the syringe Put the bag on the floor an let the fluid drip into the bag

25. Material needed Povidone-iodine or alcohol Sterile drapes, gloves, gauze Abbocath-type needle cath Local anaesthesia Syringes (10 ml / 50 ml) Aspiration set with 3-way stopcock Sterile adhesive tape Instrumentation table

26. Contraindication (relative) Coagulation disorder INR > 1.5 Thc < 50’000 Current clopidogrel use Heparin / LMWH therapeutic dosage Allowed: Aspirin Heparin / LMWH prophylactic dosage

27. How much fluid should you remove ? Diagnostic puncture: 50 – 100ml Therapeutic puncture: All fluid up to 1.5 litre (if more: risk of re-expansion pulmonary oedema) If no symptoms (no coughing, no pain, no thoracic pressure eventually more by an experienced investigator) Mixed diagnostic and therapeutic puncture (large effusion, dyspnoea and no diagnosis): Leaf about 500 ml inside (for ev. 2 nd puncture)

28. Complication of pleural puncture Pneumothorax: Air entrance through the needle (small pneumothorax) Lung puncture (larger pneumothorax) E vacuo pneumothorax (trapped, non expandable lung) Bleeding / haemothorax Hypotension, vasovagal syncope (pref. young men) Good anaesthesia, ev. premedication Atropine 0.5 mg i.v./s.c. After puncture / drainage: Chest X-ray or ultrasound !

29. Complication b efore puncture 1d after puncture Avoid ! A. mammaria parasternal Intercostal vessels dorsal

30. Thoracic ultrasound Whenever possible: thoracentesis with ultrasound! Lower complication rate Puncture of smaller pleural effusions possible S = septum R = reverberation artefacts

31. What we have to investigate (1)? Always: pH (glucose) Chemistry: Protein, LDH Differential cell count (cell count, Lyc., Neutro etc.) Cytology Suspected Infection: Gram stain (native), bacterial culture (in blood culture bottles) Ziehl-Neelsen stain, Tbc culture, ev. PCR, (adenosin-deaminase, IGRA)

32. What we have to investigate (2) ? Chylothorax Triglyceride, cholesterol Pancreatitis Amylase Haemothorax Hb, Hkr.

33. Typical constellation Low pH, high LDH, low glucose Infection (empyema, parapneum., Tbc), tumour, lupus eryth. Very low pH Rheumatoid arthritis, oesophageal perforation Mostly Lyc. (85 – 95%), few mesothelial cells Tbc , Lymphoma, Sarcoidosis Neutrophilia and high cell count (> 5000/ m l) Bacterial infection, lupus Eosinophilia (> 10%) Pneumothorax, h aemothorax, hypersensitivity (drugs), parasites, benign asbestos related PE and others

34. 2 nd puncture (if tumour is probable) Flow chart d iagnosis o f pleural effusion

35. Chest drainage Complicated pleural effusion, empyema (16 – 20 Fr) Haemothorax (16 – 20 Fr ) Recurrent symptomatic malignant pleural effusion for planned pleurodesis (talc slurry instillation) ( 12 – 16 Fr ) p os. effect of therapeutic puncture Lung expands after drainage (no trapped lung) Pneumothorax ( 12 – 16 Fr ) If > 2-3 cm between lung and chest wall on X-ray or instable If single puncture / aspiration has failed

36. C onventional technique

37. Thal Quick chest tube o ver the wire (Seldinger technique) Modern technique

38. Suction to chest tube or Heimlich valve Drainage system Heimlich valve