Hemopneumothorax Research Paper

A hemopneumothorax is a pneumothorax with bleeding in the pleural space (Coker, Aehlert and Vroman, 2011). The mechanism of injury for a hemopneumothorax is usually due to penetrating trauma. The open wound then allows for air to seep into the pleural space which then develops into a pneumothorax. The hemothorax is caused by the build-up of blood in the pleural cavity as a product of the bleeding originating from damaged blood vessels, lung and chest wall components or injury to the heart and great vessels. Hemopneumothorax usually presents with dyspnea, tachypnea and tachycardia. In more severe cases patients often suffer from hypovolemia due to massive blood loss into the pleural cavity or due to the increased severity of the pneumothorax

Hypovolemic shock occurs due to loss of circulating fluid, most often caused by haemorrhage (McKenna, Sanders and Sanders, 2012). This correlates with the hypotension seen in this patient. However patients that suffer from severe pneumothorax/ tension pneumothorax also suffer from marked hypotension. This is due to the increased pleural pressure, which in turn causes a shift in the mediastinum and the heart towards the uninjured side and also a compression on the injured lung and inferior vena cava occurs (McKenna, Sanders and Sanders, 2012). This will lead to a substantial decrease in venous return thus affecting the preload, stroke volume and cardiac output of the patient (amount of blood ejected from the left ventricle in one minute). If we take the blood pressure equation into consideration (Blood pressure= cardiac output x peripheral vascular resistance), we can now expect a decrease in blood pressure due to the decreased cardiac output (Mistovich, 2009). This will activate the baroreceptor reflex, one of the body's homeostatic mechanisms that helps to maintain blood pressure at nearly constant levels (Coker, Aehlert and Vroman, 2011). Baroreceptor reflex will cause vasoconstriction and cardiac output (namely an increase in heart rate) to try and elevate the blood pressure, but in severe cases of hypovolemia this will not work. Firstly we had to assess the severity of the hemopneumothorax so we assessed for common signs which are chest pain, dyspnea, tachypnea, tachycardia and hypotension. Late signs would be tracheal deviation, distended neck vein, peripheral shunting due to the hypovolemic shock. The patient had displayed many of these signs besides some of the late ones although diminished radial pulses were felt. I was unable to find the likelihood ratios to formally diagnose the patient with a