 Welcome back to emergency medicine video on pneumothorax. In part two we'll talk about how to investigate and how to treat patients with pneumothorax. If you haven't done so already, please refer to part one for causes and presentations of pneumothorax. The investigation and the diagnosis of pneumothorax really hinges on diagnostic imaging. Multiple modalities can be involved. They include chest x-ray, ultrasound, and CT. Please bear in mind that a tension pneumothorax should be diagnosed on clinical grounds alone. We do not have time to do diagnostic imaging since we must act quickly. If you see a patient with combination of the following signs, including increased JVP, hypotension, decreased breath sounds, and tracheal deviation, that should cure us to think that the patient has a tension pneumothorax. And we would treat the patient without confirming x-rays. If you did do an x-ray, this is what it would look like. You notice on this x-ray the medial stymium is significantly shifted to the left side. Notice the almost completely collapsed lung on the right side. Again, this is a chest x-ray you do not wish to see. You will want to fix the patient before they get to this point. How about for a regular non-tension pneumothorax? On an upright chest x-ray, we can detect a pneumothorax by seeing the pleura. Since there are now space between the parietal and visceral pleura, it can be just at the apex or along the whole side. How will that look like on a chest x-ray? Which side is the pneumothorax in on this chest x-ray? You want to look for the pleura that's now detached itself. The pneumothorax is on the right side of the patient. Can you see the pneumothorax now? That gives you the outline of the pleura. And this area is the pneumothorax. Sometimes a pneumothorax is quite small. We can help the sensitivity of picking up a pneumothorax by asking an expiratory film. Let's say we have a very small pneumothorax. Because of overlying bony structures, we may not see the pneumothorax right away. What if we ask the patient to blow all the air out of their lungs? When that happens, the overall lung volume is smaller. Now the pleura might move down further and therefore easier to see on the chest x-ray. What about in supine patient? In supine patient, the air does not rise up to the top or the apex of the lungs. Instead, it might be drifted upwards to the most top part, which is just the chest wall. And when we're shooting the chest x-ray, we may not be able to see the pleural line. What we see on a supine chest x-ray in a pneumothorax instead look like this. We see a deep sulcus sign. There is a sharp angle that the diaphragm joins the chest wall. In this chest x-ray, you can still see the pleura as well. Sometimes in smaller pneumothorax, that may not be so readily seen. So to summarize, the limitation for chest x-ray is that it cannot detect small pneumothorax. And it's challenging to diagnose a pneumothorax in a patient who's supine. Auto-sound can be used to detect pneumothorax. It has high sensitivity and specificity. We will not be showing it here, but there are videos available for this technique. Lastly, a CT scan has high sensitivity and specificity for pneumothorax. The benefit of CAT scan is that it will also tell us about underlying lung and chest pathology. However, as with all CT scan, the patient would have to be stable enough to leave the emergency department. How do we treat pneumothorax? For treating a pneumothorax, there are two main objectives. One, we want to release the air that's accumulated between the two pleura. So it does not decrease ventilation. The second objective is to stop further accumulation of air in that space. Both will divide the treatment based on the size and the cause for the pneumothorax. For spontaneous and ehydrogenic pneumothorax that are small. Depending on where you work, small pneumothoracies are defined as anything less than 3 cm from the apex. If they have a small pneumothorax and if the patient is hemodynamically stable, often your consultant will choose to leave it alone and let resolve. The patient is usually observed in the emergency department for a few hours and patients discharged home with frequent follow-ups. For larger, spontaneous and ehydrogenic pneumothorax, we need to release the air because the patient is often symptomatic. We do this by inserting a chest tube to drain the air. The chest tube is inserted in the affected side in the fifth intercostal space in the anterior axillary line. That would drain out the air that's accumulated between the two pleura. What about for tension pneumothorax when the patient is unstable? First, we want to use a way to release the air quickly since putting in a chest tube takes time. In a patient with a tension pneumothorax, we do a needle decompression with a large bore IV needle and we insert it into the second intercostal space in the mid-clavicular line. We do this first because this is the fastest way to release the air in the affected side. As the needle goes into the space, you should hear a gush of air coming through that needle. That should give you enough time since you have now decompressed the tension pneumothorax and changed it into a simple pneumothorax. You now have time to put in a chest tube. Just like before, the chest tube is still inserted in the fifth intercostal space in the anterior axillary line. After needle decompression, the hemodynamic status of the patient should improve. What about pneumothorax for trauma? In traumatic pneumothorax, there often is an air leak either from the outside with an open wound or there is a tear in the tracheal bronchial tree so the air leaks from the airway into the pleura. We will separate them in our discussion. First, we will start with an open pneumothorax. Open pneumothorax is also known as a sucking chest wound. Air is drawn in from the outside through the wound. We treat this temporarily by a three-way occlusive dressing over the open wound. In a three-way occlusive dressing, the dressing is taped onto the area. However, one edge of the dressing is not being taped down. Like this. As the patient inspires, the dressing is pulled towards the chest wall. That stops the air from going into the wound. What happens during expiration? During expiration, the air in the pleural space now escapes through the untapped edge of the dressing, creating a one-way valve effect. The patient will still ultimately need a chest tube, but this is a temporizing measure. The patient also likely need a definitive repair in the operating room. What about the patient who has a persistent air leak from the tracheoboncule tree? These patients would still need a chest tube first. Again, in the fifth intercostal space anterior axillary line. And what you would notice is that despite having a chest tube in place, the patients still have a persistent pneumothorax. This patient will need to go to the operating room for definitive repair. It's best to discuss with your surgeon. In summary, we discussed the diagnostic imaging modality for pneumothorax and its treatment. Remembering that while most pneumothorax need a chest tube, attention pneumothorax that you're going to diagnose on clinical grounds alone will need needle decompression immediately. We hope this helped your understanding of pneumothorax. Thank you for watching.