Fuente: Rachel Liu BAO, MBBCh, medicina de urgencias, escuela de medicina de Yale, New Haven, Connecticut, USA
Un neumotórax a tensión es una situación peligrosa para la vida en que el exceso de aire se introduce en el espacio pleural que rodea el pulmón, ya sea por trauma en la cavidad del pecho o como una pérdida espontánea de aire en el pulmón sí mismo. Aire atrapado dentro de la separación de causas de espacio pleural del pulmón de la pared torácica, interrumpir los mecanismos normales de la respiración. El neumotórax puede ser pequeño sin conversión a tensión, pero cuando hay una cantidad significativa y creciente de aire atrapado en la cavidad pleural, la creciente presión de este aire anormal hace que el pulmón del encogimiento y colapso, a señal de socorro respiratoria. Esta presión empuja también el mediastino (incluyendo el corazón y grandes vasos) lejos de su posición central, causando la incapacidad de la sangre volver al corazón y disminuyendo el gasto cardíaco. Neumotórax de tensión causa dolor en el pecho, falta extrema de aliento, insuficiencia respiratoria, hipoxia, taquicardia e hipotensión. Que necesitan para aliviarse emergently cuando un paciente está en extremis.
Neumotórax de tensión definitivamente es gestionados por procedimientos que permiten la remoción de aire atrapado, tales como inserción de un tubo de tórax. Sin embargo, materiales para la colocación del tubo de tórax por lo general no están disponibles fuera del ámbito hospitalario. Se necesitan medidas temporaria en pacientes deterioro antes de la llegada de hospital o mientras están siendo reunidos materiales del tubo del pecho. En estas situaciones, se realiza urgente aguja toracostomía (también llamado “aguja de descompresión”). Simplemente, es la inserción de una aguja de gran diámetro o cánula a través de la pared torácica y en el espacio pleural para que el aire dentro de la cavidad pleural para escapar. Si no está inmediatamente disponible un catéter o cánula, el procedimiento puede realizarse con una aguja larga, de gran diámetro unida a una jeringa. Aire puede ser aspirado fuera del espacio pleural con la jeringa. Una aguja de metal no puede permanecer en la cavidad pleural, ya que la punta afilada puede causar más daño; por lo tanto, tendría que ser quitado de la pared torácica cuando se aspira aire.
Needle thoracostomy is a relatively easy procedure to temporize a patient in extremis from a tension pneumothorax before a chest tube can be placed. Penetration of the chest wall muscle, subcutaneous tissue, and pleura may require significant force, so a stabbing motion of needle entry may be necessary. The most common reason for failure of this procedure is that the needle length is not sufficient enough to reach the pleura. Some patients have significant chest wall thicknesses that standard needles may not penetrate. Because of this, some suggest a lateral approach in the fourth or fifth intercostal space, in the anterior axillary or mid-axillary lines.
Risks include damage to the internal thoracic artery and intercostal nerves, which run underneath each rib. Bleeding may be significant, and may lead to hemothorax. This is the reason for performing the procedure above the third rib in the second intercostal space. Inappropriate positioning may risk subclavian artery laceration, pulmonary artery laceration, or lung parenchyma injury-all causing post-procedure bleeding. It may also cause iatrogenic creation of simple pneumothorax. As the catheter is a foreign body, pneumonia, empyema or local skin infections may develop.
Relative contraindications include prior thoracotomy, pneumonectomy, or pleurodesis, and these conditions may cause false alarm, as breath sounds are often absent after these conditions. Also, care must be taken with those in coagulation disorders, as bleeding complications may arise post-procedure. However, a tension pneumothorax is life threatening, and emergent treatment takes priority.
Needle thoracostomy, also known as “needle decompression” is a procedure performed to stabilize deteriorating patients in the life-threatening situation of a tension pneumothorax. To put it simply, the procedure involves inserting a large bore needle or cannula through the chest wall into the pleural cavity — to allow the air from within to escape.
In this video, we will first review the cause — pneumothoraces. Then, we will describe the needle thoracostomy procedure — including the prepping steps and the technique for needle insertion. Lastly, we will discuss the possible complications and contraindications associated with this intervention.
First let’s briefly talk about the etiology and types of pneumothoraces.
A pneumothorax occurs when excess air is introduced into the pleural space surrounding the lung. This may happen by trauma to the chest cavity, or due to a spontaneous leak from the lung itself. The result is separation of the lung from the chest wall and disruption of normal breathing mechanisms.
In case of a simple pneumothorax, the air can both enter and exit the pleural cavity. Hence, there is no pressure build up. Whereas in case of a tension pneumothorax, the air only enters the cavity. Thus, there can be substantial air entrapment, resulting in increased pressure or “tension”, which forces the lung to shrink and collapse. This leads to respiratory distress and the increasing pressure further displaces the mediastinum including the heart and the great vessels away from its central position, causing diminished return of the blood to the heart and therefore decreased cardiac output. A tension pneumothorax causes chest pain, extreme shortness of breath, respiratory failure, hypoxia, tachycardia and hypotension. Therefore, the “tension” needs to be relieved emergently when a patient is in extremis.
One of the methods to relieve the pressure is by needle thoracostomy – the technique that the following sections will explain.
Start by gathering the necessary supplies. These include chlorhexadine or betadine solution, an at least 2 inches long 14 or 16 gauge catheter or angiocatheter, and tape.
After performing the physical assessment steps, administer supplemental oxygen to the patient, using a nasal cannula or a non re-breather mask. Place the patient in a supine flat position, or if possible, seated with the bed elevated to a 45° angle, depending on patient comfort. Identify the second intercostal space on the affected side. It corresponds with the Angle of Louis formed by the junction of the manubrium and the sternum. Follow it to the mid-clavicular line. The landmark of needle insertion is at the intersection of second intercostal space and the mid-clavicular line. You may also perform the above procedure in the anterior axillary or mid-axillary line at the level of the fourth or fifth intercostal space. A more superior insertion site is preferred to avoid penetration into the abdominal cavity. After locating the landmark, sterilize the space using an antiseptic, like chlorhexadine. Next, place the long large bore cannula onto a sterile field and put on sterile gloves. You are now ready to perform the needle decompression.
Insert the cannula at a 90° angle to the chest wall in the mid-clavicular line, in the 2nd intercostal space above the third rib. This is to avoid damaging neurovascular structures that lie immediately below each rib. The insertion should be done in one motion and may require forceful entry. Make sure to insert the cannula to nearly its hub to reach adequate depth. A “pop” will be felt when the needle penetrates the pleura, and a rush or “hissing” of air through the needle will be audible.
Alternatively needle decompression may also be performed using a cannula attached to a 10ml syringe, which can offer better grip when puncturing the chest wall and pleura. There are two methods for doing this. The first method uses an empty syringe. Attach the syringe to the cannula and puncture the chest wall and pleura as described previously. The air escaping the pneumothorax should push plunger up — confirming appropriate depth. At the point you can remove the syringe. The second method uses a 10ml syringe half-filled with fluid, such as saline or water, attached to the cannula. Leave about 1ml of air between the fluid and the syringe’s plunger. Next, perform needle decompression, and when the pleura is punctured the pneumothorax will cause the fluid in the syringe to bubble. Remove the syringe and the metal needle of the cannula so that only the plastic catheter remains. Secure the catheter with tape.
Reassess the patient for clinical improvement. This is signified by patient appearance of less discomfort or agitation, fuller respirations taken, ability to speak more complete sentences, less tachypnea or tachycardia, improvement in hypoxia and blood pressure, and resolving tracheal deviation. If patient’s condition does not improve, repeat needle decompression by inserting another long large bore cannula adjacent to the first. Alternatively, you can move straight to chest tube placement covered in another video of this collection.
“Needle thoracostomy is a relatively easy procedure to temporize a patient in extremis before a chest tube can be placed. Penetration of the chest wall muscle, subcutaneous tissue and pleura may require significant force, so a stabbing motion of needle entry may be necessary. The most common reason for failure of this procedure is that the needle length is not sufficient enough to reach the pleura. Note that some patients have significant chest wall thicknesses that standard needles may not penetrate. Because of this, some suggest a lateral approach in the fourth or fifth intercostal space, in the anterior axillary or mid-axillary lines.”
“Risks include damage to the internal thoracic artery and intercostal nerves, which run underneath each rib. Bleeding may be significant, and may lead to hemothorax . Inappropriate positioning may risk subclavian artery, pulmonary artery laceration, or lung parenchyma injury, all causing post-procedural bleeding. It may also cause iatrogenic creation of simple pneumothoraxes. As the catheter is a foreign body, pneumonia, empyema, or local skin infection may develop.”
“Relative contraindications include prior thoracotomy, pneumonectomy or pleurodesis. Also care must be taken for those with coagulation disorders, as bleeding complications may arise post-procedure. However, a tension pneumothorax is life-threatening and emergent treatment takes priority.”
You’ve just watched JoVE’s illustration of needle thoracostomy. This is a lifesaving procedure, and although the steps are straightforward and uncomplicated, a successful procedure requires good knowledge of the surface anatomy, dexterity, and confidence. As always, thank you for watching!
