* Emergency Department Care:
Generally, any patient who requires thoracentesis in the ED should be admitted to the hospital.
1. Stable patient
- No hospital admission required:
+ Diagnostic or therapeutic thoracentesis is not required.
+ If the patient does not improve after a few days, diagnostic thoracentesis should be performed.
- Hospital admission required
+ These patients are not in acute respiratory distress, diagnostic thoracentesis is warranted.
+ Simple parapneumonic effusions have potential to become complicated effusions or empyemas and they require prompt tube thoracostomy and antibiotics.
2. Unstable patient (septic shock, respiratory distress, or with hemodynamic compromise due to the effusion)
- Initial treatment focus should be on stabilizing the airway and circulation.
- These patients require immediate diagnostic and therapeutic thoracentesis.

* Medications: common causes of pleural effusion that may treated in the ED are congestive heart failure (CHF), infection, and pulmonary embolism, medical management includes:
- CHF and pulmonary edema:
+ Nitroglycerin:
- First-line therapy for patients who are not hypotensive.
- Preload reduction and mild afterload reduction.
- Rapid onset and offset (both within minutes)
+ Diuretics: Loop diuretics decrease plasma volume and edema by causing diuresis.
- Parapneumonic effusion and empyema: Antibiotics
+ Selection based on the suspected causative microorganisms and the overall clinical picture.
+ Coverage should generally include anaerobic organisms. Options may include clindamycin, extended-spectrum penicillins, and imipenem.
- Pulmonary embolism: Anticoagulants
+ Prevent recurrent or ongoing thromboembolic disorders by inhibiting thrombogenesis.
+ When unfractionated heparin is used, the aPTT should not be checked until 6 h after the initial heparin bolus because an extremely high or low value during this time should not provoke any action.

* Procedures:
- Diagnostic thoracentesis
- Therapeutic thoracentesis: to remove larger amounts of pleural fluid is used to alleviate dyspnea and to prevent ongoing inflammation and fibrosis in parapneumonic effusions.

- Tube thoracostomy: Although small, freely flowing parapneumonic effusions can be drained by therapeutic thoracentesis, most larger effusions and complicated parapneumonic effusions or empyemas require drainage by tube thoracostomy.

- Pleurodesis or pleural sclerosis:
+ used for recurrent malignant effusions, such as in patients with lung cancer or metastatic breast or ovarian cancer
+ the goal of therapy is to palliate symptoms while minimizing patient discomfort, hospital length of stay, and overall costs.
+ successful only if the pleural space is drained completely before pleurodesis and if the lung is fully reexpanded to appose the visceral and parietal pleura after sclerosis.