1. Tension Pneumothorax

2. Learning objectives SIMPLE PNEUMOTHORAX CAUSES OF TENSION PNEUMOTHORAX
RECOGNITION & ASSESSMENT
MANAGEMENT

3. Simple pneumothorax Air outside of the lung
OPEN PNEUMOTHORAX e.g. direct chest trauma, stab wound
CLOSED PNEUMOTHORAX e.g. spontaneous, mechanical ventilation
A pneumothorax is a collection of air inside the chest, but outside the lung itself.
Commonly, this is caused by damage to the pleura overlying the lung, from trauma, surgical intervention, or rupture of alveoli during mechanical ventilation.
Pneumothoraces may also arise spontaneously.
In a simple pneumothorax, the air that has leaked into the pleural space is not under pressure, usually because there is no ongoing leak between the lung tissue and pleural space, and the pneumothorax therefore does not expand with each breath. A small simple pneumothorax may resolve spontaneously or with needle aspiration. Larger pneumothoraces (perhaps greater than 20% of lung volume) usually require an intercostal drain to aid resolution.
A pneumothorax may be described as open, closed or tension
An open pneumothorax has a connection between the outside air and the pleural space, e.g. stab wound, intraop­erative thoracotomy.

4. WHAT IS TENSION PNEUMOTHORAX
Progressive build-up of air in the pleural space
‘One-way-valve' effect
Increasing pressure within chest
Mediastinum shift
Obstructs venous return to the heart
Leads to circulatory instability and may result in traumatic arrest.
Tension pneumothorax is the progressive build-up of air within the pleural space, usually to a lung laceration which allows air to escape into the pleural space but not to return.
Positive pressure ventilation may exacerbate this 'one-way-valve' effect.
Progressive build-up of pressure in the pleural space pushes the mediastinum to the opposite hemithorax, and obstructs venous return to the heart. This leads to circulatory instability and may result in traumatic arrest.
However, particularly in a patient receiving mechanical ventilation, there is a significant risk of conversion from a simple to a tension pneumothorax, where a proportion of each inspired breath escapes through a leak between the lung and the pleural space, and increases the size of the pneumothorax. This incremental expansion of the pneumothorax increases the gas pressure within that side of the chest. This increasing pressure collapses the lung and twists the mediastinum and great veins, with detrimental effects on both gas exchange and haemodynamics. This may be fatal if untreated or unrecognized, and this may be a particularly rapid process (a few minutes) for patients receiving mechanical ventilation.
The identification of which type of pneumothorax is present is therefore important, since it will affect the urgency and nature of required treatment

5. Causes: Traumatic and Non-traumatic
TRAUMATIC (OPEN)
Penetrating chest wall
Blunt force trauma
NON-TRAUMATIC (CLOSED)
Spontaneous Pneumothorax
Positive pressure ventilation
COPD (bullae rupture)

6. CXR of tension pneumothorax
Tracheal Deviation
Mediastinal shift
Depression of the hemi-diaphragm
This CXR taken in a patient with severe blunt trauma to the chest and a left tension pneumothorax illustrates the classic features of a tension:
Deviation of the trachea away from the side of the tension.
Shift of the mediastinum.
Depression of the hemi-diaphragm.
With this degree of tension pneumothorax, it is not difficult to appreciate how cardiovascular function may be compromised by the tension, due to obstruction of venous return to the heart. This massive tension pneumothorax should be detectable clinically and, in the face of haemodynamic collapse, be treated with emergent thoracostomy - needle or otherwise.

7. CXR of tension pneumothorax
Tracheal Deviation
Mediastinal shift
Depression of the hemi-diaphragm
This CXR taken in a patient with severe blunt trauma to the chest and a left tension pneumothorax illustrates the classic features of a tension:
Deviation of the trachea away from the side of the tension.
Shift of the mediastinum.
Depression of the hemi-diaphragm.
With this degree of tension pneumothorax, it is not difficult to appreciate how cardiovascular function may be compromised by the tension, due to obstruction of venous return to the heart. This massive tension pneumothorax should be detectable clinically and, in the face of haemodynamic collapse, be treated with emergent thoracostomy - needle or otherwise.

8. SIGNS & SYMPTOMS OF TENSION PNEUMOTHORAX
R e c o g n I t I o n
SIGNS & SYMPTOMS OF TENSION PNEUMOTHORAX
TACHYPNOEA & DYSPNOEA
HYPOXIA
EXPANSION 
PERSUSSION NOTE 
BREATH SOUNDS 
TACHYCARDIA
HYPOTENSION
 TRACHAE 
NECK VEINS 
CIRCULATORY COLLAPSE
PEA ARREST
ANY UNEXPLAINED TACHYCARDIA, HYPOTENSION + INCREASE IN AIRWAY PRESSURE IS HIGHLY SUGGESTIVE OF TENSION PNEUMOTHORAX
The signs of a tension pneumothorax are deviation of the trachea away from the side with the tension,
a hyper-expanded chest, with little movement on inspiration,
an increased percussion note.
The central venous pressure is usually raised
More commonly the patient is tachycardic and tachypnoeic, and may be hypoxic.
Tension pneumothorax may develop insidiously, especially in patients with positive pressure ventilation.
Any unexplained tachycardia, hypotension and rise in airway pressure are strongly suggestive of a developing tension.

9. signs of tension pneumothorax
The signs of a tension pneumothorax are deviation of the trachea away from the side with the tension,
a hyper-expanded chest, with little movement on inspiration,
an increased percussion note.
The central venous pressure is usually raised
More commonly the patient is tachycardic and tachypnoeic, and may be hypoxic.
Tension pneumothorax may develop insidiously, especially in patients with positive pressure ventilation.
Any unexplained tachycardia, hypotension and rise in airway pressure are strongly suggestive of a developing tension.

10. Assessment – BASK 2 BASICS
LOOK, LISTEN, FEEL!
ABCDE ASSESSMENT
ASCULTATION
EXPOSE THE PT & LOOK AT THE CHEST .
Is there a penetrating injury? change in shape? chest wall deformity? asymmetric chest movement? bulging neck veins?!?,
HANDS ON & FEEL…..EXPANSION OF CHEST WALL, L =R? does one side rise & THE OTHER NOT?
Chest auscultation - Routine baseline assessment
Undertaken in conjunction with
Inspection: looking at the chest wall to determine normal & abnormal outlines
Percussion: the chest wall is struck with the fingertips to obtain sounds/vibrations that give indications of the positioning and consistency of the lungs
Palpation: feeling over the chest wall to id normal & abnormal structures

11. MANAGEMENT CHEST XRAY ?? Yes or NO NEEDLE THORACOSTOMY?
Do we OR Don’t we?
CHEST DRAIN INSERTION
In the absence of haemodynamic compromise, it is prudent to wait for the results of an emergent chest X-ray prior to intervention. This will avoid patients such as that shown, where a right upper lobe collapse due to endobronchial intubation resulted in hypoxia and tracheal deviation - mimicking a tension pneumothorax on the opposite side The patient received an unnecessary left chest tube.
However, some clinicians will argue you should never have a CXR of TP, as it should be recognized immediately as part of the primary survey! ATLS guidelines

12. Management – needle decompression
2nd rib space in the mid- clavicular line
Immediate rush of air
Converts a tension pneumothorax into a simple pneumothorax
Associated with complications!
Classical management of tension pneumothorax is emergent chest decompression with needle thoracostomy.
A 14-16G intravenous cannula is inserted into the second rib space in the mid-clavicular line.
The needle is advanced until air can be aspirated into a syringe connected to the needle.
The needle is withdrawn and the cannula is left open to air.
An immediate rush of air out of the chest indicates the presence of a tension pneumothorax. The manoeuver essentially converts a tension pneumothorax into a simple pneumothorax!
Needle thoracostomy is probably not as benign an intervention as previously thought, and often is simply ineffective in relieving a tension pneumothorax.
If no rush of air is heard on insertion, it is impossible to know whether there really was a tension or not, and whether the needle actually reached the pleural cavity at all. Some patients with a raised BMI may have very thick chest walls.
Needle thoracostomies are also prone to blockage, kinking, dislodging and falling out. Thus a relieved tension may re-accumulate undetected. More importantly is the possibility of lung laceration with the needle, especially if no pneumothorax is present initially. Air embolism through such a laceration is also a real concern.
Needle decompressions has been extensively debated - The conclusion of the debate was:
Needle decompression can be associated with complications.
It should not be used lightly.
It should never be used just because we don't hear breath sounds on one side. BUT
In clear cut cases: shock with distended neck veins, reduced breath sounds, deviated trachea, it could be life saving. It is essentially used in prehospital care as a temporary measure.

13. MANAGEMENT – chest drain insertion
Chest tube placement is the definitive treatment of tension pneumothorax. Chest tubes should be immediately available and placement is usually rapid.
The controlled placement of a chest tube is preferable to blind needle thoracostomy.
This is provided the patient's respiratory and haemodynamic status will tolerate the extra minutes it takes to perform the surgical thoracostomy.
Once the pleura is entered (blunt dissection), the tension is decompressed and chest tube placement can be performed without haste.
This is especially true of the patient who is being manually ventilated with positive pressure!
NB: The presence of chest tubes does not mean a patient cannot develop a tension pneumothorax.
Chest tubes placed posteriorly, CAN be blocked as the overlying lung is compressed backwards when patients are supine.
Chest tubes in supine trauma patients should be placed anteriorly to avoid this complication.
There are several types of chest drain, used for different purposes, each with specific characteristics – in TP, a large bore chest drain is used.
Large­bore chest drain insertion is often a painful procedure. Adequate analgesia and, if required, sedation, should be provided in a timely manner. Large­bore chest drains are often supplied with a metal trocar. This should be removed prior to drain insertion.
Most drains are inserted in the 4th or 5th intercostal space in the mid­axillary line, but occasionally drains may be placed in the anterior chest wall or other sites (e.g. for loculated collections or pneumothoraces).
Once the drain is inserted, it should be secured. Purse string sutures should not be used because they convert a linear wound into a painful, unsightly scar. Simple interrupted sutures are recommended to close the wound and to secure the drainage tube.
The position of the drain is usually confirmed using a chest X­ray.

14. Chest drain management
UNDERWATER SEAL (hospital setting)
ONE-WAY VALVE e.g. Heimlich-type Flutter valve (pre-hospital setting)
Most chest drains in critical care are managed using an underwater seal system. This allows drainage of air and fluid from the pleural space into a container, while preventing any backflow of fluid or air into the pleural space. Obviously, if the drainage container is held above the level of the insertion point, such backflow becomes more likely.
ONE WAY VALVE CHEST DRAIN SYSTEM - The chest drain is connected to a one­way valve system. In some situations, a simple Heimlich­type flutter valve is used, such as when an underwater seal drain is not available or transport of the patient with an underwater seal drain is difficult. A Heimlich­type flutter valve is a one­way valve consisting of a plastic tube with a flexible, flattened inner latex tube attached internally at one end. Air, blood, or fluid flows into the latex tube and out at the other end. The latex tube collapses on itself at rest, thus preventing any backflow of air or fluid into the chest.
SWINGING - Fluid in a drain that is patent, correctly placed in the pleural space and connected to an underwater seal should ‘swing’. This means the fluid in the chest drain tubing rises and falls with respiration. For a spontaneously breathing patient, inspiration should make the fluid rise towards the patient and expiration should make it fall. The converse is true for a patient receiving positive pressure ventilation. This is because, during positive pressure ventilation, inspiration is due the generation of a positive pressure within the chest, while spontaneous inspiration is a result of a negative pres­sure developing within the chest.
BUBBLING: If a drain is placed for a pneumothorax, it should ‘bubble’. This is the air of the pneumothorax being displaced from the pleural space into the drain. The degree of bubbling will depend on the size of air leak. A large leak may persist throughout the respiratory cycle, while a smaller leak may only occur during expiration. Resolution of the pneumotho­rax will lead to cessation of bubbling.
A non­bubbling drain may be one that has resolved the underlying pneumothorax, or it may be malfunctioning, perhaps because it is blocked or kinked. Likewise, a drain that does not swing may be blocked or kinked. Identification of the problem should lead to appropriate management – drain removal, unblocking, or possibly replacement.

15. FINALLY……….. Youtube! Pneumothorax & tension