3.2 Open Pneumothorax & Massive Hemothorax Management

3.2 Open Pneumothorax & Massive Hemothorax Management

Open Pneumothorax ("Sucking Chest Wound")

An open pneumothorax occurs when a penetrating chest wall wound creates a direct communication between the external environment and the pleural space.

Pathophysiology

Normal ventilation relies on negative intrathoracic pressure. When a chest wall defect is greater than two-thirds of the diameter of the trachea (approximately 1 cm in adults), air preferentially enters the pleural space through the chest wall defect during inspiration rather than through the trachea, because the defect offers lower resistance to airflow. This results in rapid collapse of the ipsilateral lung, severe hypoventilation, hypoxia, and impaired mediastinal movement ("mediastinal flutter") that compromises venous return.

Emergency Nursing Management

1. Immediate 3-Sided Occlusive Dressing: Cover the wound immediately with a sterile, non-porous dressing (e.g., petrolatum gauze or commercial chest seal) taped on three sides only.
   • Mechanism: During inspiration, the dressing sucks against the skin to block atmospheric air from entering the pleural space. During expiration, the untaped fourth side opens, allowing trapped intrapleural air and blood to escape.
   • Critical Warning: Taping the dressing on all four sides creates a closed system. If an underlying parenchymal lung leak exists, a 4-sided dressing will trap air within the pleural space, rapidly converting an open pneumothorax into a life-threatening tension pneumothorax. If the patient deteriorates after dressing application, temporarily remove or burp the dressing to relieve trapped air.
2. Definitive Care: Place a chest tube (tube thoracostomy) through a separate, clean anatomical site (typically 4th or 5th ICS anterior axillary line), NOT through the open wound itself. Following chest tube insertion and lung re-expansion, the open chest wall defect is surgically repaired.

Massive Hemothorax

A massive hemothorax is defined as the rapid accumulation of >1,500 mL of blood in the pleural cavity upon initial chest tube placement, or ongoing bleeding exceeding 200 mL/hour for 2 to 4 consecutive hours.

Pathophysiology & Causes

Massive hemothorax results from traumatic laceration of major systemic or pulmonary blood vessels, most commonly intercostal arteries, internal mammary arteries, or major hilar vessels. Accumulated blood causes dual compromise:

1. Respiratory Failure: Direct mechanical compression of the ipsilateral lung, causing severe alveolar hypoventilation and V/Q mismatch.
2. Hemorrhagic Shock: Massive intravascular volume loss leading to profound hypovolemia, decreased cardiac preload, and circulatory collapse.

Clinical Assessment & Diagnostic Differentiation

Diagnostic Key: Differentiation between tension pneumothorax and massive hemothorax centers on percussion note (dullness vs hyperresonance) and neck vein appearance (flat vs distended). However, both conditions cause hypotension and absent breath sounds, and both require immediate resuscitation.

Resuscitation & Autotransfusion

Initial resuscitation for massive hemothorax prioritizes volume restoration and drainage.

Vascular Access & Resuscitation

• Establish two large-bore peripheral IV lines (14-gauge or 16-gauge) or a rapid infusion catheter / central line.
• Activate the Massive Transfusion Protocol (MTP) to administer balanced 1:1:1 ratios of packed red blood cells (PRBCs), fresh frozen plasma (FFP), and platelets to prevent trauma-induced coagulopathy.

Autotransfusion (Cell Salvage)

Autotransfusion involves collecting shed pleural blood from the chest tube and reinfusing it into the patient's circulation.

• Indications: Hemodynamically unstable patients with massive hemothorax where compatible donor blood is delayed.
• Advantages: Immediate availability, warm blood, compatible autologous tissue, preserved 2,3-DPG levels.
• Nursing Standards & Contraindications:
  • Blood must be collected into a specialized sterile canister with citrate anticoagulant (e.g., ACD-A or heparinized saline).
  • Blood must be reinfused within 4 hours of collection to prevent bacterial contamination and hemolysis.
  • Contraindications: Contamination of chest contents with enteric pathogens (diaphragmatic rupture with gastrointestinal leakage), systemic sepsis, or presence of topical hemostatic agents.

Indications for Emergency Operative Thoracotomy

Not all hemothoraces require surgery; most (>80%) are managed with chest tube drainage alone. However, emergent surgical intervention (thoracotomy/sternotomy) is mandatory when specific bleeding thresholds are met:

1. Initial Drainage Threshold: Immediate output of >1,500 mL of blood upon chest tube insertion.
2. Ongoing Drainage Threshold: Continuous bleeding of >200 mL/hour for 2 to 4 consecutive hours.
3. Hemodynamic Instability: Persistent shock despite aggressive blood product resuscitation.
4. Expanding Hemothorax: Radiologic evidence of an expanding chest mass or failure of the lung to re-expand despite chest tube suction.