Flail chest: Description, Causes and Risk Factors:
Flail chest describes a situation in which a portion of the rib cage is separated from the rest of the chest wall, usually due to a severe blunt trauma, such as a serious fall or a car accident. This affected portion is unable to contribute to expansion of the lungs, which creates some obvious problems for the patient (hampered breathing) and can contribute to some not-so-obvious ones. Flail chest is a serious condition that can lead to long-term disability and even death.
A ?ail chest occurs when an isolated segment of the chest wall loses bony continuity with the rest of the thoracic cage. This is usually as a result of multiple rib fractures. In other words, the ?ail chest can be de?ned as two or more ribs fractured in two or more places. The ?ail segment therefore consists of several ribs, but may also involve the vertebral column or sternum. Flail chest is an area of thoracic trauma that often presents a difficult management problem. Before we consider the available strategies for this relatively common condition, it is important to have an understanding of both thoracic anatomy and the basic principles of the pathophysiology of thoracic trauma.
Thoracic injuries are responsible for 25% of trauma deaths in the UK and are a significant contributory factor to another 25%. Within the UK the most common cause of thoracic injury is blunt trauma. Blunt thoracic trauma is almost exclusively caused by rapid deceleration or crush injuries sustained in road traffic accidents. The majority of these injuries occur to the drivers or front seat passengers of cars. Within this group 30-40% of victims sustain rib fractures, of which 20-30% also sustain a ?ail chest.
The exact incidence of flail chest is not precisely known. The Major Trauma Outcome Study of more than 80,000 patients documented about 75 patients with flail chest injuries. The true incidence of flail chest may be even higher than those noted above, based on newer diagnostic modalities and procedures including MSCT scans (Multislice CT scans) of the chest. The incidence of flail chest at non-trauma center facilities is currently unknown.
Symptoms of flail chest can include:
Bruises, grazes, and/or discoloration in the chest area.
Adetailed history of the accident should be obtainedfrom the best available source, with particular emphasis on the mechanism of injury. Special note should betaken of the previous cardiac, respiratory and vascularstatus of the patient. At this stage it is also useful tocarry out a detailed physical examination of the patientif clinically stable. The following investigations aremandatory.
Routine blood test.
- Arterial blood gas (ABG).
- Electrocardiograph monitoring.
- The plain chest radiograph.
- CT and MRI scans.
The treatment of ?ail chest remains controversial. There are strong arguments in favor of all treatment modalities (conservative, elective ventilation and surgery). The initial management of any patient with ?ail chest must be based on simple principles — minimize further injury to the underlying lung, provide adequate analgesia, and maintain oxygenation.
Isolated flail chest may be successfully managed with aggressive pulmonary toilet including facemask oxygen, CPAP/IPPV, and chest physiotherapy. Adequate analgesia is of paramount importance in patient recovery and may contribute to the return of normal respiratory mechanics. Early intubation and mechanical ventilation is paramount in patients with refractory respiratory failure or other serious traumatic injuries.
Tracheotomy and frequent flexible bronchoscopy should be considered to provide effective pulmonary toilet. Surgical stabilization is associated with a faster ventilator wean, shorter ICU time, less hospital cost, and recovery of pulmonary function in a select group of patients with flail chest. Open fixation is appropriate in patients who are unable to be weaned from the ventilator secondary to the mechanics of flail chest. Persistent pain, severe chest wall instability, and a progressive decline in pulmonary function testing in a patient with flail chest are also indications for surgical stabilization. Open fixation is also indicated for flail chest when thoracotomy is performed for other concomitant injuries. There is no role for surgical stabilization for patients with severe pulmonary contusion. The underlying lung injury and respiratory failure preclude early ventilator weaning. Supportive therapy and pneumatic stabilization is the recommended approach for this patient subset.
NOTE: The above information is educational purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.