Which patients with a parapneumonic effusion need a chest tube?

TO PLACE A CHEST TUBE OR NOT

For category 1 or 2 effusions, treatment with antibiotics alone is typically enough. Category 3 effusions usually do not respond to antibiotics alone and may require complete drainage of the fluid with or without a chest tube depending on whether loculations are present, as loculations are difficult to drain with a chest tube. Category 4 effusions require both antibiotics and chest tube placement.

WHAT TYPE OF CHEST TUBE?

Studies have shown that small-bore chest tubes (< 20 F) are as efficacious as larger tubes (≥ 20 F) for the treatment of complicated parapneumonic effusion and empyema.^6,7 Studies have also shown that the size of the tube makes no difference in the time needed to drain the effusion, the length of hospital stay, or the complication rate.^8,9 Based on these studies, a small-bore chest tube should be placed first when clinically appropriate. When a chest tube is placed for empyema, computed tomography should be performed within 24 hours to confirm proper tube placement.

ADVANCED THERAPIES FOR EMPYEMA

Empyema treatment fails when antibiotic coverage is inadequate or when a loculation is not drained appropriately. Options if treatment fails include instillation of fibrinolytics into the pleural space, video-assisted thora­scopic surgery, and decortication.

The role of fibrinolytics has not been well-established, but fibrinolytics should be considered in loculated effusions or empyema, or if drainage of the effusion slows.¹⁰ Video-assisted thora­scopic surgery is reserved for effusions that are incompletely drained with a chest tube with or without fibrinolytics; studies have shown shorter hospital length of stay and higher treatment efficacy when this is performed earlier for loculated effusions.¹¹ Decortication is reserved for symptomatic patients who have a thickened pleura more than 6 months after the initial infection.¹² Timing for each of these procedures is not clearly defined and so must be individualized.

TAKE-AWAY POINTS

• Parapneumonic effusion occurs concurrently with pneumonia and with a high frequency.¹
• Effusions are associated with an increased risk of death.³
• Categorizing the effusion helps guide treatment.
• Chest tubes should be placed for some cases of complicated effusion and for all cases of empyema.
• A small-bore chest tube (< 20 F) should be tried first.