Synopsis
Perform and supervise pleural aspiration safely, request samples that answer the clinical question, and interpret pleural-fluid biochemistry, microbiology and cytology without losing urgent infection or malignancy pathways.
- Define whether aspiration is diagnostic, therapeutic or both, and whether the result will change drainage, antimicrobial, cancer or heart-failure management before inserting a needle.
- Thoracic ultrasound must be used by a trained operator to confirm fluid, identify diaphragm and solid organs, and select a contemporaneous safe site; a remote skin mark is invalid after the patient moves.
- Check consent, laterality, indication, observations, allergies, haemostasis and antithrombotic plan, patient positioning, asepsis, equipment, sample labels and rescue arrangements through the local checklist.
Key red flags
Purulence, positive microbiology, pH at or below 7.2, low glucose, high LDH, loculation and ongoing sepsis support complicated parapneumonic effusion or empyema. Pus or high-risk non-purulent fluid generally needs timely drainage in addition to antimicrobial treatment.
Investigation priorities
Confirm the presence, depth and accessibility of pleural fluid, identify septation and prevent injury to diaphragm, lung and abdominal organs.
Management branches
Diagnostic or therapeutic pleural aspiration is being considered.
- Review imaging and define what aspiration will decide, assess urgency and alternatives, and obtain informed consent covering pain, bleeding, infection, organ injury, pneumothorax and failure to obtain an answer.
- Check observations, laterality, allergies, antithrombotic medicines and relevant haemostasis under local policy, while recognising that urgent sepsis may require an individual risk decision.
Key medicines
Local anaesthetic for pleural aspirationInfiltrate skin, subcutaneous tissue and periosteal tissues using the locally approved agent, concentration and maximum weight-adjusted limit, aspirating before incremental administration.