Tension pneumothorax resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Mohamed Moubarak, M.D. [2]

Synonyms and keywords: Collapsed lung; air around the lung; air outside the lung

Tension Pneumothorax Resident Survival Guide Microchapters
Overview
Causes
Diagnosis
Treatment
Do's
Don'ts

Overview

Tension pneumothorax is a medical emergency resulting from accumulation of air in the pleural cavity. Air enters the intrapleural space as a result of disruption in the parietal pleura, visceral pleura or tracheobronchial tree, this disruption results in the formation of a one way valve which allows the air to enter in the pleural cavity (during inspiration) but prevents its escape (during expiration). Subsequently, pressure inside the pleural cavity rises high enough to cause respiratory and cardiovascular failure. Tension pneumothorax can occur as a result of trauma, ventilation, resuscitation and preexisting lung disease. It should be managed immediately with emergency needle decompression.

Causes

Life Threatening Causes

Tension pneumothorax is a life-threatening condition and must be treated as such irrespective of the underlying cause.

Common Causes

Tension pneumothorax can be a complication of primary, or secondary pneumothorax. The most common causes of tension pneumothorax are:

• Mechanical ventilation
• Trauma
• Central venous catheter
• Cardiopulmonary resuscitation
• Emphysema
• Chronic obstructive pulmonary disease
• Asthma

Diagnosis

Shown below is an algorithm depicting the diagnostic approach of tension pneumothorax based on the British Thoracic Society Pleural Disease Guideline 2010.

Characterize the symptoms: Tension pneumothorax requires immediate intervention. Diagnosis should be made based on the history and physical examination findings. ❑ Dyspnoea ❑ Chest pain ❑ Cyanosis ❑ Sweating ❑ Anxiety ❑ Fatigue ❑ Decreased consciousness (in late stages)

Identify the precipitating factors: (Diagnosis of pneumothorax is more likely if any of the following is present) ❑ Recent invasive procedures ❑ Thoracentesis ❑ Central venous catheter ❑ Bronchoscopy ❑ Pleural biopsy ❑ Mechanical ventilation ❑ Cardiopulmonary resuscitation ❑ Presence of chest drains ❑ Hyperbaric oxygen treatment ❑ Chest wall trauma

Examine the patient: Vital signs ❑ Pulse: ❑ Tachycardia ❑ Weak pulse ❑ Respiratory rate: ❑ Tachypnea ❑ Blood pressure ❑ Hypotension Focused chest examination: Inspection ❑ Enlarged involved hemithorax ❑ Jugular venous distension (absent in severe hypotension) Palpation ❑ Reduced lung expansion on the affected side ❑ Trachea shifted to the opposite side ❑ Decreased vocal fremitus over the affected hemithorax ❑ Displacement of the apex beat Percussion ❑ Hyperresonance over the affected hemithorax Auscultation ❑ Diminished breath sounds on the affected side Additional findings in ventilated patients: ❑ Decreased oxygen saturation ❑ Increase in inflation pressure ❑ Increase in peak airway pressure ❑ Airway pressure alarm

Rule out the following alternative diagnosis clinically: ❑ Acute myocardial infarction ❑ Pericardial tamponade ❑ Pulmonary embolism

Stable patient

Unstable patient

❑ Proceed with imaging studies to confirm the diagnosis Imaging studies: ❑ Perform chest X-ray ❑ Perform serial chest X-ray every 6 hours to rule out pneumothorax in cases of trauma. Picture courtesy of Wikidoc.org Left-sided tension pneumothorax ❑ Air in the pleural cavity ❑ Contralateral deviation of mediastinum ❑ Increased thoracic volume ❑ Ipsilateral flattening of heart border ❑ Mid diaphragmatic depression ❑ Chest CT scanning ❑ For uncertain or complex cases Picture courtesy of Wikidoc.org Left-sided pneumothorax. A chest tube is in place, the lumen (black) can be seen adjacent to the pleural cavity (black) and ribs (white). ❑ Ultrasonography (indicated in supine trauma patients)

❑ Administer high concentration oxygen ❑ Perform emergent needle aspiration (14-16 G) ❑ Instantaneous escape of air confirms the diagnosis of tension pneumothorax

Treatment

Initial supportive measures: (In cases of chest wall trauma) ❑ Assess airway, breathing, and circulation (ABC) ❑ Immediately cover penetrating chest wounds with an occlusive or pressure bandage ❑ Administer 100% oxygen ❑ Seek expert consultation (thoracic surgeon)

Emergency needle decompression: ❑ Aseptic preparation ❑ Use two alcohol-based skin disinfectants ❑ Use 14-16 G intravenous cannula ❑ Site ❑ 2nd intercostal space, midclavicular line(of affected hemithorax) ❑ Use 4th or 5th intercostal space on mid or anterior axillary line, if initial decompression is failed because of thick chest wall ❑ Listen for gush of air Don`t repeat needle aspiration unless there were technical difficulties ❑ Watch how to do a needle decompression {{#ev:youtube|UvHJ4pjNh2Q|400|How to do a needle decompression}} Video adapted from Youtube.com

Admit the patient

Insert chest drain ❑ Obtain the informed consent ❑ Insert chest tube immediately after the needle decompression ❑ Administer initial parenteral dose of first-generation cephalosporins (to decrease the risk of empyema and pneumonia) ❑ Use imaging guidance ❑ A recent chest X-ray before the procedure ❑ Standard erect postro-anterior chest x-ray ❑ Ensure asepsis ❑ Administer adequate analgesics ❑ Make sure that following equipments are available: ❑ 1% lignocaine ❑ Alcohol based skin cleanser ❑ Sterile drapes, gown, gloves ❑ Needles, syringes, gauze swabs ❑ Scalpel, suture (0 or 1-0 silk) ❑ Chest tube kit ❑ Closed system drain (including water) and tubing ❑ Dressing ❑ Clamp ❑ Site ❑Insert chest tube at the triangle of safety bordered by: ❑ Superiorly: the base of the axilla ❑ Anteriorly: lateral edge of pectoralis major ❑ Laterally: lateral edge of latissimus dorsi ❑ Inferiorly: the line of the fifth intercostal space ❑ Insert the chest tube ❑ Leave the cannula in place until bubbling is observed in the chest drain underwater seal system ❑ Check chest tubes frequently, as they can become plugged or malpositioned Avoid complications: ❑ Pain ❑ Administer analgesics ❑ Administer local anesthesia ❑ Intrapleural infection ❑ Use aseptic technique ❑ Wound infection ❑ Use antibiotics prophylaxis

Discharge and follow up ❑ All patients should be followed up by respiratory physicians ❑ Advise to return to hospital if increasing breathlessness develops ❑ Advice to avoid air travel ❑ Advice to avoid diving

Do`s

• Tension pneumothorax diagnosis should be made based on the history and physical examination findings.
• Serial chest radiographs every 6 hrs on the first day after injury to rule out pneumothorax is ideal.
• Leave the cannula in place until bubbling is confirmed in the chest drain underwater seal system
• Suspect tension pneumothorax with blunt and penetrating trauma to the chest
• Differentiate tension pneumothorax from pericardial tamponade, and myocardial infarction.
• Suspect tension pneumothorax in patients on mechanical ventilations, who have a rapid onset of hemodynamic instability or cardiac arrest, and require increasing peak inspiratory pressures.
• Check chest tubes, as they can become plugged or malpositioned and stop functioning.
• Give adequate analgesia to patients before chest tube insertion, as the procedure is extremely painful.
• Refer the patient to respiratory specialist within 24h of admission.

Dont`s

• Don`t start using chest radiograph or CT scan unless in doubt regarding the diagnosis and when the patient's clinical condition is sufficiently stable.
• Don`t use large bore chest drains.
• Don`t repeat needle aspiration unless there were technical difficulties.

References

Template:WikiDoc Sources