Abstract              Bibliografia 

Gilda Cinnella

Thorax trauma are extremely frequent in our country.
Recent data account that, in Italy, 5% of the admission to the intensive care are due to this pathology.(1)
In Usa  trauma of the thorax are 30% of the admissions in the Trauma center (2). The mortality related is high. On the accident site the mortality is 25%, while in Hospital mortality is 4-8% for isolated thorax trauma and 35% of patients with multiorgan damage (2).
The mortality has a triphasic pattern:
a) few minutes after the trauma, 
b) few hours afterwards for lesions potentially lethal, but curable if treated  during the so- called golden hour c) days or weeks afterwards due to complications.
In this last instance the treatment is essential in order to reduce the mortality.

Initial  treatment.
The first aid of the trauma patient is  equal to the approach  to any critical patient.
Control of the respiratory airway must be obtained and ventilation, if necessary, must be promptly available (obstructed airway, pneumothorax, impaired mechanical ventilation)
Good vein access is mandatory and a neurologic assessment must be promptly performed.
Urgent surgical operation is rare in the thorax trauma.
After the aid is important to check for the presence of pulmonary and cardiovascular lesions that could develop also in the following days.

Instrumental examinations
The exams to be performed are: thorax x ray, ct scan, angiography, echocardiography and broncoscopy.

Thorax x ray is essential in order to evaluate the condition of the thorax cage, the presence air and fluid, the extension of the lung contusion.
Patients with a fracture of the first and second ribs has in 40% of the case a myocardial contusion or major vascular damage, while in the presence of fracture of the last three ribs a lesion of the liver or the spleen should be suspected.
Damage of the aorta could be shown with a mediastinal enlargement or a deviation  rightwards of the esophagus.

Trans esophageal echocardiography allows the cardiac chambers and the function of the heart. 
Moreover Tee  is very important to diagnose dissection and traumatic lesions of the aorta.

Ct scan is nowadays performed routinely, and is important to evaluate lesions and pathologies non apparent on the x ray.
Bronchoscopy is mandatory in all cases and particularly when exists a trauma of the airways.
The statistics reported in the literature show the importance of this exams and its reliability.
The percentage of false negative is very low, and this happens when the exam is performed in difficult condition. Bronchoscophy must be performed according to the radiological  and clinical picture of the patient.

Hemodinamic assessment 
The hemodinamic control of the patient is, of course, essential.
The choice of the fluid management and of the drugs is related to the clinical conditions of the patient(tab. 1); myocardial contusion  and neurogenic shock can cause hemodinamic impairment.
A good way to deal with hypotension is a fluid infusion of 500-2000 ml/hrs.when blood loss is controlled.
If the pressure rises than the cause was hypovolemia otherwise other underlying mechanisms should be thought.
In the case of continuous blood loss or cardiac dysfunction  inotropic drugs should be instituted (tab. 2,3).

Resuscitation treatment
The admission rate to the intensive care is 25%.
The main case of admission are: severe respiratory insufficiency and flail chest or associated lesions

Respiratory insufficiency
The variations of the respiration in the presence of flail chest has been described as "pendulluft". The air inspired goes  from the damaged lung to the other during inspiration, and viceversa during expiration (4).
However this theory has been discussed  clinically and in the experimental setting (4)
The pain due to the presence of  flail chest can cause a superficial pattern of ventilation.
In this area of disventilation and athelectasia  can be originated in the underlying lung.
Lung contusion can reduce the lung compliance and to increase the ventilation mismatch.
Several factors are responsible of the alterated ventilation pattern in the presence of trauma of the chest.
The goal of the treatment is to counteract the different factors the influence the lung dynamic
The main action should go toward a reduction of the pain, a correction of pneumothorax, and to reestablish a correct lung ventilation (6)
When the respiratory insufficiency persist mechanical ventilation should instituted.(7) 

Mechanical ventilation differentiated for the lung
The mechanical ventilation of the patients with trauma of the thorax is performed in the usual way.
Particular attention is needed in order to control the airway pressure allowing the closure of lesions. (2,4,5).
When only one lung is damaged the normal pattern of artificial ventilation can worsen the gas exchange (8,9).
The air ventilated goes preferentially to the healthy lung which has a normal compliance. In this instance a separated ventilation becomes mandatory.

Complication and prognosis
All the factors described play an important role in the developing of complications. And in the related prognosis.

Conclusion
Trauma of the thorax  is a dramatic event which has a high mortality.
The therapeutic  approach must be correctly instituted in order to diminish the rate of complications and the related mortality.

Gilda Cinnella
Ricercatore - Dipartimento dell'Emergenza
 e dei Trapianti d'Organo 
Sezione di Anestesia e Rianimazione - 
Università di Bari