How are traumatic pneumothorax and/or hemothorax managed in a patient undergoing laparotomy for splenic injury?

How are traumatic pneumothorax and/or hemothorax managed in a patient undergoing laparotomy for splenic injury?

Pneumothorax and/or hemothorax are the most frequent consequences of chest injury and require timely recognition and treatment. Concerns about exacerbating spine injuries or producing adverse hemodynamic changes preclude obtain-ing a chest radiograph in the sitting position, which is required for the diagnosis of a pneumothorax and recogni-tion of the magnitude of a hemothorax. For these reasons, while supine chest radiographs are obtained routinely in all major trauma patients, additional measures may be neces-sary to diagnose pneumothorax and hemothorax when their presence is suspected. Computed tomography (CT) of the chest is highly specific for this purpose, and even a small amount of air in the pleural cavity can be recognized by this method. Unfortunately, in some instances a preoperatively undiagnosed pneumothorax may enlarge during surgery for associated injuries, and result in severe hemodynamic and oxygenation abnormalities and potentially death if not recognized in time.

The clinical signs and symptoms of pneumothorax in anesthetized patients receiving positive-pressure ventilation include elevation of peak airway pressure, decreased lung compliance, decreasing oxygen saturation, decreased breath sounds on the affected side and, in extremis, severe hypoten-sion, and even cardiac arrest. A chest radiograph can provide the diagnosis even in the supine position if there is a large amount of intrapleural air; however it may be difficult or impossible to obtain during emergency surgery.

Without a radiologically confirmed diagnosis, placement of a 14G needle between the fourth and fifth ribs (the fourth intercostal space) in the midaxillary line, the thinnest region of the chest wall even in obese patients, may be indicated in unstable patients. Nevertheless, atelectasis, bronchial obstruc-tion, or migration of intra-abdominal contents into the chest through a traumatic diaphragmatic defect can mimic the clinical findings of pneumothorax and lead to chest tube placement that is not indicated. Recently, the sonographic diagnosis of pneumothorax has gained some recognition.

Normally, when the lung is imaged by a 3.5–7.5 MHz ultrasound probe, it moves beneath the chest wall during each inspiration, and so-called comet-tail artifacts, multi-ple echodense spots at the surface of the lungs, appear in the image. In the presence of pneumothorax, neither lung movement (sliding) nor comet-tail artifacts can be observed in the ultrasound image.

Hemothorax may also cause hemorrhagic shock, medi-astinal shift, and airway management difficulties. The volume and rate of blood drained via a chest tube determine the necessity of thoracotomy. Drainage of >1,200 mL of blood upon placement of a chest tube, and/or continuing drainage of >200 mL/hour for 4 hours, or >100 mL/hr for 4 hours in patients older than 60 years, are indications for thoracotomy. Other indications for emergency surgery include significant hypotension and/or tachycardia, persistence of “white lung” on the chest radiograph in the presence of a properly placed chest tube, difficulty of ventilation, pericardial tamponade, massive air leak from the chest tube, and cardiac or great vessel injury.