Thoracentesis Learning Module
This web page is composed of six sections designed to re-familiarize practitioners with the Thoracentesis procedure.
Print all the necessary documents here or at other points throughout the module.
*Note: This module does not replace medical training and must be used in conjunction with clinical judgment. Acting practitioner is ultimately responsible for the safety of procedures.

Principle Risks
Rare Risks
-
Infection
-
Visceral organ puncture
-
Vasovagal reaction
-
Anaesthetic/sedative reactions
- Print Consent Form
Contraindications
- Active infection over site
- Extremis
Precautions
- INR > 1.5
- Platelet < 50,000/mm3
- Volume < 10mm thick on decubitis Xray
There are no absolute contraindications for thoracentesis, only parameters that increase risk.
Print Procedure Note

1Positioning
- Place patient in sitting position on edge of bed with arms resting on table
- Landmark the top of the effusion with auscultation and percussion
- Mark needle insertion site 5-10 cm lateral to the spine and at least 1 or 2 intercostal spaces below the top of the effusion.
- DO NOT insert needle below 9th rib
2Ultrasound
- Visualize effusion with ultrasound and re-mark needle insertion site based on most accessible fluid pocket
3Sterilizing and Anesthetizing
- Sterilize the area 3 times utilizing antiseptic solution
- Dress with sterile gloves and apply a sterile drape
- With a 25 gauge needle, inject a “wheel” of lidocaine into the dermis overlying the prospective needle insertion site
- With a 22 gauge needle, anaesthetize the deeper tissues, intermittently aspirating, until obtaining pleural fluid. Inject a small volume of lidocaine in the pleural space
- Utilize a ‘walking technique’ while advancing the needle in order to avoid neurovascular structures
4Introducing the Catheter Device
- Use a scalpel to create a small nick in the skin and subcutaneous tissue where you will insert your thoracentesis needle
- Introduce your catheter device where the chest wall has been previously anaesthetized, intermittently aspirating until pleural fluid is obtained
- Advance the plastic catheter portion (without the needle component) until the black/blue demarcating line is no longer visible
5Obtaining fluid
- While the stopcock is in the lock position, attach a 60 cc syringe to the syringe port
- Turn the stopcock toward the self-sealing valve and withdraw fluid into the syringe
- When diagnostic sampling is complete, turn the stopcock to the patient port before disconnecting the syringe; divide fluid into specimen bottles (including aerobic/anaerobic culture bottles)
- For therapeutic thoracenteses, attach a vacuum bottle(s) to drain additional pleural fluid
6Caution
- DO NOT remove greater than 1.5 Litres
- STOP / PAUSE the procedure if the patient develops significant cough, chest pain or increased dyspnea
7Post Procedure Care
- Have the patient hum (or hold their breath at end expiration) while removing catheter device from the chest wall
- Place clean bandage over procedural site
- Order post‐procedure vitals and chest XRAY
- Documentation sheet must be in the chart!
8
All specimens should be hand-delivered to their destinations
Videos:
Thomsen, Todd W., et al. “Thoracentesis.” New England Journal of Medicine 355.15 (2006): e16.
Kind thanks to CareFusion for their permission.