The Development of Pneumothorax: the Mechanical Process of Breathing - Research Paper Example

 Pneumothorax is considered to be a pathological condition in which the pleural cavity indicates the presence of gas. During the normal respiration in a human being the pressure within the pleural cavity which is referred to as the intrapleural pressure is below the atmospheric pressure in a normal respiratory cycle and only is raised at the time of expiration. But in pneumothorax an inlet is provided for the air to enter the pleural cavity and this inlet basically functions unidirectional allowing the entry of air whereas preventing the normal exit. This results in the buildup of pressure due to increased entry of air into the pleural cavity and difficulty in expiration of air. This accumulation of air in the pleural cavity is referred to as pneumothorax (Guyton et al 1996, Ganong and Robbins et al 2005, Wojciechowski, B. 2006, Mohan 2007). The development of pneumothorax occurs in the setting of invasion of the pleura of the viscera or the mediastinum or the parietal pleura. A patient with traumatic pneumothorax might also present with fractures of the ribs. The patient will present with pain in the chest and difficulty in breathing. The heart rate also increases and the patient experiences depression of the respiratory process. The resonance of the chest wall on the side of the trauma increases along with reports of raised resonance in the sternum as well. The breathing sounds become low or they may be absent. At the same time the increased pressure can also result in pushing of the medistinum to the opposite side. The trachea might also move from its original position due to the increased pressure in the direction opposite to the injury. This results in breach of the organs of the other side which include the heart and the unaffected lung. If this push is great it can also affect the blood supply to the heart. This can be seen as a shift in the position of the apex of the heart in the patient. As the condition deteriorates further the patient can lose consciousness. The increased pressure in the pleural cavity can result in the collapse of the lung which is present on the side of the injury and this can result in reduced oxygen supply. Decreased blood pressure and decreased partial pressure of oxygen has also been reported in certain cases. Pain in the epigastrium has also been associated with pneumothorax. The decreased oxygenation of the hemoglobin can lead to increased levels of deoxygenated hemoglobin in the blood which can lead to cyanaosis. The patient can be put on ventilation in these cases but care must be taken that the patient does not develop tension pneumothorax in which the patient presents with a very abrupt drop in the cardiac functioning with or without drop in blood pressure. The levels of oxygen also reduce. The veins in the patient can also become distended along with the expansion of the chest on the side of the pneumothorax. The patient might also complain of pain on the side of the pneumothorax and the patient might present shoulder pain which occurs as the radiating pain from the site. The patient would also complain that the pain increases during respiration. This is because of the buildup of pressure (Bascom et al 2009, Wojciechowski 2006, Jindal et al 2008, Heffner et al. 2000, and Harris et al 2005) Bottom of Form Flail chest on the other hand is defined as the “breaking of two or more than two ribs in at least two places,” (Bastos et al 2008). This can lead to loss of normal functioning of the rib cage. This is because the broken ribs do not work in coordination with the rest of the rib cage during the mechanical process of breathing. The fractures result in tearing of the muscles in close approximation of the bones. This causes cessation of the normal functioning of the muscles which can result in abnormality in the normal respiratory process as these muscles may be the muscles of respiration. The pain associated with this condition is excruciating. This condition can result in leading to pneumothorax or the accumulation of blood in the thoracic cavity which is known as haemothorax. The bleeding which results due to the trauma can also lead to the seepage of blood in to the layers of the lungs. Within one day the ratios of oxygen and carbon dioxide in the blood become disrupted. The patient would present with severe pain. On exanimation it would be observed that thoracic cage does not move completely on normal respiration as it does in the normal subjects. The patient experiences difficulty in breathing along with inability to cough due to the unbearable pain. The symmetry of the thoracic cage is lost. Underlying structures which include the lung and the heart might also get damaged. The patient also has increased heart rate and the patient breathes rapidly. On deep breathing the patient complains of increased pain. The damage to the lung can lead to pulmonary contusion due to leakage of fluid from the vasculature of the lungs. This might also be visible on viewing the patient. The patient can also be in shock, present with a contusion or may have deteriorating condition depending upon the nature of the trauma. The patient can also present with metabolic acidosis which results due to the increased carbon dioxide levels. The values of the tidal volume are lower than normal in the case of flail chest (Bastos et al 2009, Wanek et al 2004, Gwinnutt et al 2009). Pneumothorax is a complication associated with flail chest. With the trauma and fracture to the ribs of the patient, it can result in the creation of an inlet on the side of trauma which can be the cause for the entry of air into the pleural cavity and hence lead to increased pleural pressure. Both conditions together can alter the normal respiratory mechanism of an individual. The pressure within the pleural cavity increases as a result of this condition. The pressure raise makes it difficult for the expiration of air. This is also because normal movement of the rib cage is also restricted. On the other hand damage to the lung can also result in contusion. This fluid which leaks from the vessels can enter the alveoli and hence disrupt their normal functioning and capability of oxygen exchange with the blood. The elastic recoil of the lung occurs both because of raised pressure as well as restricted movement. The mediastinum shift alters the vasculature of the heart particularly the inferior vena cava. The shift of the mediastinum mainly occurs if the pressure within the cavity exceeds and leads to the shifting of the structures. This results in disruption of the venous flow to the heart. The high intrapleural pressure prevents the proper functioning of the lungs and hence disrupts the normal breathing mechanism (Wanek et al 2004, Bascom et al 2009, Wojciechowski 2006) The respiration normally occurs due to the maintenance of a pressure gradient between the pleural cavity and the alveoli. This pressure is disrupted due to the inbuilt pressure in the cavity because of the air. The pressure between the alveoli (lungs) and the cavity becomes equal and hence the pressure gradient does not exist for allowing the proper exchange of gases. Also the muscles of the thoracic cavity function to increase the capacity of the cavity during inspiration and reduce the capacity of the cavity during expiration. Since the patient has flail chest and spasm of the muscles this movement is also led to. The increased pressure in the alveoli might also lead to the collapse of the alveoli and inhibit the oxygenation of the incoming blood. Since the expansion and the contraction of the cavity does not occur the lung also completely recoils and stops its optimal functioning and collapses. Thus the respiratory mechanisms are altered. The changes in pressure also lead to differences in the exchange of gases between the blood and the alveoli. The lung at the aide of the injury collapses in such condition and the level of oxygenated blood also drops. This leads to deterioration of the respiratory mechanisms in the patient (Sherwood, L. 2006). The patient had a flail chest as well as traumatic pneumothorax and he presented with all the signs and symptoms associated with it. His increased heart rate, difficulty in breathing was all supportive of this fact. The patient became disoriented and had altered levels of consciousness because of this condition as he eventually has most probably developed tension pneumothorax. This build up of tension can eventually be fatal. Hence he was put on a mechanical ventilator. It is necessary to ensure that the mechanical ventilator is kept at low tidal volumes. This is because mechanical ventilation can lead to further damage to the lung as ventilator associated lung injuries can occur. This happens because of the increase in the pressure build up which further aggravates the condition (Gajic et al 2004). A chest computed tomography is very essential as well because it assists in the better determination of the clinical condition in this case because this is a traumatic thoracic injury which can result in aortic injury. The aortic injury mostly occurs in the setting of motor vehicular accidents and it can prove to be lethal. Chest computed tomography is also an important determinant of the vascular injuries that might have resulted in the setting of the accident. Occult pneumothorax can also occur in the setting of such injuries and this can be missed in the chest radiograph so this can also be seen by the chest computed tomography (Plurad et al 2008). The patient’s heart rate should be constantly monitored. The most important relation is also established between this particular procedure and the flail chest. This is because in this condition it serves to determine the damage that the fractured ribs have caused to the underlying structures in the thoracic cavity and it also a better determinant of the damages and fractures of the ribs. As soon as this patient was received his blood sample should have been sent for checking the pressures of the different gases in the blood. Along with this the blood group matching should also be done and blood for transfusion should be arranged. When the patient is out on ventilation the transfusion can prove to be beneficial in the improvement of the patient’s condition. The chest of the patient should be fully exposed. This is because the respiratory movements of the patient can be observed in this way. If the breath sounds are not seen in the axillary region after the patient is put on ventilation it is indicative of the fact that he is suffering from tension pneumothorax. The patient should also be checked for fractures of the sternum which should also be ruled out. This is because these fractures can also result in motor vehicular accidents and they can be present along with the fracture of the ribs (Porter 2009). Also the patient presents with a medical emergency and the normal functioning of the heart is important to be checked. This is because altered levels of gases and changes in respiration as well as the other changes that occur due to the pneumothorax and flail chest can push a patient towards the development of myocardial problems (Bascom et al 2009). Needle thoracocentesis is not a good choice in this case. This is because the patient is already in a condition which deteriorating. And needle thoracocentesis can result in false outcomes which are presented largely due to the fact that the chest thickness and the length of the needle cannot necessarily make the needle reach the appropriate location where there is build up of air. Hence this cannot be performed. Lateral thoracostomy can prove to be beneficial for this patient since it is the treatment for releasing the tension and particularly in patients who present in critical conditions. As a second step to this a tube can also be used to pull out the air from the cavity. In this case application of an anesthetic to the area between the fourth and fifth intercostals space needs to be done. This should be done with extreme care in this patient because he has fractured ribs as well. The finger should then be used and inserted into the pleural space after a clean cut is made. This reduces the pressure in the cavity. To further enhance the results the patient should then be performed with tube thoracostomy. This tube is connected with a device of suction device that has a fixed pressure in it. This is to maintain a constant pressure in the thoracic cavity. This pressure should be set at the normal value which would lead to the development of negative pressure in the cavity as it normally is and partially relief the condition. Care should be taken that the tube is not forced in this place since this can lead to harm organs and the vasculature and this patient already is suffering from flail chest with rib fractures. This is a very important factor because there have been mortalities related with the insertion of the tube in the heart itself as well as there is a very high probability of rupture to the large vessels. This process of lateral thoractomy and the insertion of tube are referred to as the pleural decompression. This procedure is the most suitable technique in this condition because it is employed in the treatment of pneumothorax in mechanically ventilated patients (Owen et al2005, Vincent et al2006, Kossmann et al. 2008) The flail chest is has separate protocols of treatment. Though this protocol is very similar to that for pneumothorax but it should be integrated with that for the pneumothorax and this would hence result in the most favorable results. The respiration rate should be checked, proper outlet for the air should be provided and the levels of the fluid should be maintained. It should be realized that the pain experienced in the case of flail chest is very excruciating and this pain management by means of analgesics is essential. Epidural analgesia can be performed to relieve this pain. This requires great care or another option can be intrapleural block. The opoids are also used to relieve the pain via the intravenous route and they may also be given in association with the NSAIDS. The injury also causes asymmetry of the chest and hence this should be also be dealt with accordingly. This provides for the main methods employed for flail chest. Though ventilation is mostly avoided but since the condition of the patient was moving down this was the best option at that time. The ribs can be fixed at the period of the performance of thoracotomy. If the follow up of the patient is not very significant and he needs to be kept n mechanical ventilation, it is a better option to surgically fix the ribs since it is considered as a way to reduce the span of ventilation time. Steroids are contraindicated in this condition (Gwinnutt et al 2009 Graham et al.2001) References: Bascom, R. & Benninghoff M.G (2009). Pneumothorax. Medscape Top of Form Bastos R., Calhoon J.H., & Baisden C.E. (2008). 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