Flail Chest Treatment & Management

Internal pneumatic stabilization for flail chest was popularized in the 1950s, but this treatment has subsequently been shown to be unnecessary in most patients without respiratory compromise. In a mid-1970s report, Trinkle et al provided compelling evidence that many patients fared better with adequate pain control and pulmonary toilet (including medical management of their pulmonary injury) than those placed on mechanical ventilation.^[8] This remains the standard today. Mechanical ventilation is reserved for patients with persistent respiratory insufficiency or failure after adequate pain control or when complications related to excessive narcotic use occur. Patient-controlled analgesia (PCA) machines, oral pain medications, and indwelling epidural catheters form the mainstay of current treatment.

Two recent clinical reports, one from Turkey (prospective)^[9] and one from Japan (retrospective),^[10] showed that continuous positive airway pressure (CPAP) by mask may decrease mortality and nosocomial pneumonia in the ICU, but CPAP by mask does not appear to change the length of ICU stay.

Surgical stabilization of the chest was rarely considered necessary in the past, but increasing numbers of reports of positive outcomes in more severe cases are now available in the world literature. Both external (lower efficacy) and internal stabilization have been advocated, usually in reports from outside the United States. As previously noted in traumatic causes, however, severity of respiratory failure is less a result of either the paradoxical motion of the chest wall (tidal volume abnormalities) or chest wall instability. Accordingly, surgical stabilization is still not routinely performed, although many reports show a benefit in decreasing mechanical ventilator days, long-term outcome, and overall lower cost of hospitalization in select patients with severe flail chest.^{[11] [12, 13, 14, 15]}

In general, operative fixation is most commonly performed in patients requiring a thoracotomy for other reasons or in cases of gross chest wall deformity. Flail chest from multiple myeloma, sternal absence, or total sternectomy more frequently responds well to surgical fixation. Underlying pulmonary injury with respiratory insufficiency resulting from changes in tidal volume and minute ventilation in these patients is rare.

Assessment of the severity of underlying pulmonary contusion versus chest wall instability should direct the need for surgical fixation. Preoperatively, a double-lumen endotracheal tube should be considered in patients with flail chest undergoing fixation.

The current literature suggests that both ends of a fractured rib must be stabilized for operative intervention to be most effective. Judet struts, Kirschner (K-) wires, and even prosthetic mesh secured with methylmethacrylate techniques have been described in the literature, but no large randomized prospective trial has been completed to compare the techniques at this time. Because of the increasing interest in surgical stabilization, there are multiple commercially available fixation devices within the last few years.

Routine postthoracotomy care with ICU or surgical step-down level observation and close monitoring of respiratory parameters is crucial.

Follow-up chest x-rays and pulmonary function tests determine the resolution of underlying pulmonary pathology and any possible long-term disability as a result of the initial condition.

Reports in the medical literature note a high level of long-term disability in patients sustaining flail chest. Beal and Oreskovich reported a 22% disability rate with over 63% having long-term problems, including persistent chest wall pain, deformity, and dyspnea on exertion.^[16] Kishikawa et al, however, noted resolution of altered pulmonary function within 6 months, even with chest wall deformity still present.^[17]

Overall, patients with flail chest have a 5-10% reported mortality if they reach the hospital alive. Patients who do not need mechanical ventilation do better statistically, and overall mortality seems to increase with increasing injury severity scores (ISS), age, and number of total rib fractures.

Few long-term follow-up studies regarding flail chest are available. In the absence of concomitant lethal injuries, Freedland et al reported adverse outcomes to be more likely with more severe associated injuries noted by ISS scoring, excessive blood loss and transfusion requirements, bilateral flail chest, and patient age older than 50 years.^[18] A report by Albaugh and associates in New Jersey noted flail chest mortality increased 132% with each decade of life,^[19] but another report by Athanassiadi and associates found no correlation with age.^[20] Both studies noted increasing mortality with increasing ISS. As previously noted, some reports suggest a high rate of disability after flail chest; however, most patients do well and return to normal function after 6-12 months.

Further improvements in emergency medical systems and the education of prehospital personnel may increase the observed frequency of flail chest in the future. Improvements in noninvasive ventilation techniques like CPAP and pain control may also improve currently observed outcomes. Prevention, including safer automobiles and newer airbag design may affect the incidence and outcome of these multifactorial injuries.