Pleural Effusion Diagnostic and Management Algorithm (BTS 2023)

Algorithm Steps

1. ▶

   Start

   Pleural Effusion Identified

   CXR or CT shows pleural fluid collection

   1. ●

      Action

      Clinical Assessment

      History and examination

      • Symptoms: dyspnea, pleuritic pain, cough
      • Duration and progression
      • History: HF, liver disease, malignancy, infection
      • Medications: drugs causing effusion
      • Physical exam: dullness, decreased breath sounds
      1. ◆

         Decision

         Obvious Transudative Cause?

         Clinical diagnosis sufficient?

         • Bilateral effusions with heart failure
         • Known cirrhosis with ascites
         • Nephrotic syndrome
         • Typical clinical picture
         1. ●

            Action

            Treat Underlying Cause

            No diagnostic tap needed initially

            • Optimize heart failure treatment
            • Diuretics for transudate
            • Monitor response
            • Tap if no response or atypical features
            1. ●

               Action

               Diagnostic Thoracentesis

               Ultrasound-guided aspiration

               • USS guidance mandatory (BTS 2023)
               • Aspirate 20-50mL for diagnosis
               • Send: pH, protein, LDH, glucose, cytology, culture
               • Consider: Amylase, cholesterol, triglycerides, ADA
               1. ◆

                  Decision

                  Apply Light's Criteria

                  Exudate if ANY met

                  • Pleural protein/serum protein >0.5
                  • Pleural LDH/serum LDH >0.6
                  • Pleural LDH >2/3 upper limit normal
                  • EXUDATE if any positive
                  1. ●

                     Action

                     Transudate

                     Usually cardiac, hepatic, or renal cause

                     • Common: Heart failure, cirrhosis, nephrotic
                     • Less common: Hypothyroidism, PE, constrictive pericarditis
                     • Treat underlying condition
                     • Therapeutic tap if symptomatic
                     1. ✓

                        Outcome

                        Discharge & Follow-up

                        Plan based on etiology

                        • Repeat CXR in 4-6 weeks if resolving
                        • Outpatient follow-up for ongoing management
                        • Respiratory referral for complex cases
                  2. ◆

                     Decision

                     Exudate - Further Workup

                     Determine etiology

                     • Infection (parapneumonic, empyema, TB)
                     • Malignancy
                     • Inflammatory (RA, SLE)
                     • PE, pancreatitis, drugs
                     1. ◆

                        Decision

                        Infection Markers?

                        pH, glucose, appearance

                        • pH <7.2 = Complicated parapneumonic/empyema
                        • Glucose <40 mg/dL = Complicated effusion
                        • Pus = Empyema
                        • Positive Gram stain/culture
                        1. ⚠

                           Warning

                           Complicated Parapneumonic/Empyema

                           Requires drainage

                           • Chest drain insertion
                           • Small bore (10-14Fr) often adequate
                           • IV antibiotics
                           • Consider intrapleural fibrinolytics (tPA/DNase)
                           • Surgical referral if not improving
                        2. ●

                           Action

                           Simple Parapneumonic

                           Antibiotics, monitor

                           • pH >7.2, glucose normal
                           • Antibiotics alone usually sufficient
                           • Repeat imaging in 48-72h
                           • Tap if enlarging or not improving
                     2. ◆

                        Decision

                        Cytology/Other Tests

                        For non-infectious exudate

                        • Cytology positive = Malignant
                        • High ADA = TB consideration
                        • Chylothorax: Triglycerides >110
                        • Amylase elevated = Pancreatic/esophageal
                        1. ●

                           Action

                           Malignant Pleural Effusion

                           Palliative management focus

                           • Symptom relief priority
                           • Options: Repeat aspiration, IPC, pleurodesis
                           • Indwelling pleural catheter (IPC) increasingly used
                           • Talc pleurodesis if good performance status
                           • Involve palliative care
                        2. ●

                           Action

                           Undiagnosed Effusion

                           Consider further investigation

                           • CT thorax with contrast
                           • Repeat thoracentesis
                           • Thoracoscopy (VATS or medical)
                           • Pleural biopsy if TB suspected
                           • PET-CT for occult malignancy