Trauma to the thoracic wall can be due to penetrating wounds and can lead to pneumothoraces or haemothoraces.
Rib fractures can be caused by trauma or coughing (particularly in the elderly), and can occur in patients with osteoporosis. Pathological rib fractures may be due to metastatic spread from carcinoma of the bronchus, breast, kidney, prostate and thyroid. Ribs can also become involved by a mesothelioma. Fractures may not be readily visible on a PA chest X-ray, and lateral X-rays and oblique views may be necessary.
Pain may prevent adequate chest expansion and coughing and this can lead to pneumonia. Treatment is with adequate analgesia using oral agents or by local infiltration or an intercostal nerve block. More than one fracture in one rib can lead to a flail segment with paradoxical movement, i.e. part of the chest wall moves inwards during inspiration. This can produce inefficient ventilation and may require intermittent positive- pressure ventilation.
RUPTURE OF THE TRACHEA OR A MAJOR BRONCHUS
Rupture of the trachea or even a major bronchus can occur during deceleration injuries, leading to pneumothorax, surgical emphysema, pneumomediastinum and haemoptysis. Surgical emphysema is caused by air leaking into the subcutaneous connective tissue; this can also occur after the insertion of an intercostal drainage tube. A pneumomediastinum occurs when air leaks from the lung inside the parietal pleura and extends along the bronchial walls.
RUPTURE OF THE OESOPHAGUS
Rupture of the oesophagus from external injury, endoscopic procedures, bougienage or necrotic carcinoma may lead to the serious complication of mediastinitis. This requires vigorous antibacterial chemotherapy.
This causes widespread fluffy shadows on the chest X-ray due to intrapulmonary haemorrhage. This may give rise to adult respiratory distress syndrome or shock lung.
Kyphoscoliosis may be congenital, idiopathic, due to disease of the vertebrae such as tuberculosis or osteomalacia, or due to neuromuscular disease such as Friedreich’s ataxia or poliomyelitis. The respiratory effects of severe kyphoscoliosis are often more pronounced than might be expected and respiratory failure and death often occur in the fourth or fifth decade. The abnormality should be corrected at an early stage if possible. Bilevel positive airway pressure ventilation delivered through a tightly fitting nasal mask is the treatment of choice for respiratory failure.
Limitation of chest wall movement is often well compensated by diaphragmatic movement and the respiratory effects of this disease are relatively mild. It is associated with upper lobe fibrosis of unknown aetiology. Pectus excavatum and carinatum Pectus excavatum causes few problems other than embarrassment due to the deep vertical furrow in the chest, which can be corrected surgically. The heart is seen to lie well to the left on the chest X-ray. Pectus carinatum (pigeon chest) is often the result of rickets. No treatment is required.
‘Dry pleurisy’ is the term used to describe pleurisy when there is inflammation but no appreciable effusion. The localized inflammation produces sharp localized pain, made worse on deep inspiration, coughing and occasionally on twisting and bending movements. Common causes are pneumonia, pulmonary infarct and carcinoma. Rarer causes are rheumatoid arthritis and systemic lupus erythematosus.
EPIDEMIC MYALGIA (BORNHOLM DISEASE) is due to infection by Coxsackie B virus. This illness is common in young adults in the late summer and autumn and is characterized by an upper respiratory tract illness followed by pleuritic pain in the chest and upper abdomen with tender muscles. The chest X-ray remains normal and the illness clears within I week.
A pleural effusion is an excessive accumulation of fluid in the pleural space. It can be detected on X-ray when 300 ml or more of fluid is present and clinically when 500 ml or more is present. The chest X-ray appearances range from the obliteration of the costophrenic angle to dense homogeneous shadows occupying part or all of the hemithorax. Fluid below the lung (a subpulmonary effusion) can simulate a raised hemidiaphragm. Fluid in the fissures may resemble an intrapulmonary mass.
The physical signs
This is by pleural aspiration. The fluid that accumulates may be a transudate or an exudate. TRANSUDATES. Effusions that are transudates can be bilateral. The protein content is less than 30 g litre-I and the lactic dehydrogenase is less than 200 IU litre -I. Causes include:
• Heart failure
• Hypoproteinaemia (e.g. nephrotic syndrome)
• Constrictive pericarditis
• Ovarian tumours producing right-sided pleural
effusion – Meigs’ syndrome
EXUDATES. The protein content of exudates is greater than 30 g litre-I and the lactic dehydrogenase is greater than 200 IU litre-I. Causes include:
Pleural biopsy may be necessary to diagnose the cause of the effusion. Treatment is of the underlying condition.
MALIGNANT PLEURAL EFFUSIONS
Malignant pleural effusions that reaccumulate and are symptomatic can be aspirated to dryness followed by the instillation of a sclerosing agent such as tetracycline or bleomycin. Effusions should be drained slowly since rapid shift of the mediastinum causes severe pain and occasionally shock. This treatment produces only temporary relief.
This is due to the accumulation of lymph in the pleural space, usually resulting from leakage from the thoracic duct due to trauma or to infiltration by carcinoma.
This is the presence of pus in the pleural space and can be a complication of pneumonia.
‘Pneumothorax’ means air in the pleural space. It may occur due to trauma to the chest or may be spontaneous. Pneumothorax may be localized if the visceral pleura has previously undergone adhesion to the parietal pleura, or generalized if the whole hemithorax contains air. Normally the pressure in the pleural space is negative but this is lost once a communication is made with atmospheric pressure; the elastic recoil pressure of the lung then causesit to partially deflate. If the communication between the airways and the pleural space remains (an open pneumothorax), a bronchopleural fistula is created. Once the communication between the lung and the pleural space is obliterated, air will be reabsorbed at a rate of 1.25% of the total radiographic volume of the hemithorax per day. Thus, a 50% collapse of the lung will take 40 days to reabsorb completely once the pneumothorax is closed. It has been postulated that a valvular mechanism may develop through which air can be sucked during inspiration but not expelled during expiration. The intrapleural pressure remains positive throughout breathing, the lung deflates further, the mediastinum shifts, and venous return to the heart decreases, with increasing respiratory and cardiac embarrassment. This tension pneumothorax is very rare unless the patient is on positive ventilation.
This usually occurs in young males, the male-to-female ratio being 6 : 1. It is caused by the rupture of a pleural bleb, usually apical, and is thought to be due to congenital defects in the connective tissue of the alveolar walls. Both lungs are affected with equal frequency. Often these patients are tall and thin.
In patients over 40 years of age, the usual cause is underlying chronic bronchitis and emphysema. Rarer causes include bronchial asthma, carcinoma, a lung abscess breaking down and leading to bronchopleural fistula, and severe pulmonary fibrosis with cyst formation. The sudden onset of unilateral pleuritic pain or increasing breathlessness are the usual presenting features. If the pneumothorax enlarges, the patient becomes more breathless and may develop pallor and tachycardia. here may be few physical signs if the pneumothorax is small. The characteristic features and management. The main aim is to get the patient back to active life as soon as possible.