![]() The two subtypes of atraumatic pneumothorax are primary and secondary. There are two types of pneumothorax: traumatic and atraumatic. ![]() Air can enter the pleural space by two mechanisms, either by trauma causing communication through the chest wall or from the lung by rupture of the visceral pleura. The degree of collapse determines the clinical presentation of pneumothorax. The air accumulation can apply pressure on the lung and make it collapse. It occurs when air accumulates between the parietal and visceral pleurae inside the chest. A thoracic radiograph should be taken after placement of a small-bore chest tube to ensure adequate location in the thorax.A pneumothorax is a collection of air outside the lung but within the pleural cavity. These are an acceptable alternative, although they typically require general anesthesia or heavy sedation combined with local analgesia for placement because of the need to tunnel the catheter under the skin. ![]() Sterile red rubber feeding catheters also are recruited occasionally for use as chest tubes. Small-bore chest tubes are less effective when continuous suction is required because generation of continuous negative pressure (–15 to –25 cm H 2O) appears to collapse the chest tube. They are proving particularly popular in patients with moderately large-volume pneumothoraces, and their use appears to be more comfortable than placement of standard large-bore chest tubes or intermittent thoracocentesis. These catheters (14 gauge ) are placed readily using a modified Seldinger technique and can be secured easily in an awake patient. It is characterized by a barrel-shaped (hyperinflated) appearance to the chest cavity with limited thoracic motion despite vigorous movements of the head and neck in an attempt to ventilate, and by hypoxemia and cardiovascular collapse caused by continued entrapment of air within the pleural space due to lack of an escape pathway.Ī small-bore chest tube has been introduced in recent years as a modification of a jugular catheter (MILA chest tube). A tension pneumothorax can result from any type of pneumothorax, although it is usually closed. Pneumothorax can be characterized as traumatic, spontaneous, or iatrogenic, and as open or closed ( Pawloski and Broaddus, 2010). In emergency practice, limited ultrasonography of the thoracic cavity (thoracic focused assessment with sonography for trauma ) also has been used to detect pneumothorax in dogs and cats with suspected traumatic pneumothorax ( Lisciandro, 2008). Computed tomography (CT) will also highlight pneumothorax ( Figure 165-2). Diagnosis of pneumothorax may be confirmed with thoracic radiographs ( Figure 165-1) or by a positive thoracocentesis. Clinical signs of pneumothorax include a short and shallow (“restrictive”) breathing pattern and absent lung sounds on thoracic auscultation. Pneumothorax develops when there is either leakage of air from damaged or diseased pulmonary parenchyma or external damage to the thoracic cavity resulting in the entrance of air into the chest cavity from the atmosphere. Normal intrapleural pressure varies depending on the phase of respiration, with inspiration associated with more negative pressure during spontaneous breathing. This negative intrathoracic pressure helps to maintain lung expansion and promote venous return. Normal intrapleural pressure is approximately −5 cm H 2O, which means that, in the healthy dog or cat, intrapleural pressure is negative compared with the atmosphere. ![]() P neumothorax is defined as free air in the pleural space.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |