Merck Manual

Please confirm that you are a health care professional

Loading

Flail Chest

By

Thomas G. Weiser

, MD, MPH, Stanford University School of Medicine

Last full review/revision May 2020| Content last modified May 2020
Click here for Patient Education
Topic Resources

Flail chest is multiple fractures in ≥ 3 adjacent ribs that result in a segment of the chest wall separating from the rest of the thoracic cage; it is a marker for injury to the underlying lung.

A single rib may fracture in more than one place. If multiple (3 or more) adjacent ribs fracture in ≥ 2 places, the breaks in each rib result in a segment of chest wall that is not mechanically connected to the rest of the thoracic cage (flail segment). This flail segment moves paradoxically (ie, outward during expiration and inward during inspiration—see Figure: Flail chest).

Patients are at high risk for respiratory complications, mainly because the large amount of force required to cause a flail chest typically causes a significant underlying pulmonary contusion. In addition, the paradoxical motion of flail chest increases the work of breathing, and chest wall pain tends to limit deep inspiration and thus maximal ventilation.

Flail chest

Flail chest

Diagnosis

  • Clinical evaluation

Diagnosis of flail chest is clinical, ideally by observing the paradoxical motion of the flail segment during breathing. However, this motion may be difficult to see if inspiratory depth is limited by pain or obtundation due to other injuries. The paradoxical motion does not occur if the patient is mechanically ventilated, but the flail segment may be identified by its more extreme outward movement during lung inflation. Palpation can often detect crepitus of the flail segment and confirm abnormal chest wall motion.

Chest x-ray can help confirm bone fractures and usually shows underlying pulmonary contusion; x-ray does not show cartilaginous disruption.

Treatment

  • Supportive care

  • Sometimes mechanical ventilation

  • Sometimes rib fracture repair

Humidified oxygen is given to patients with flail chest. Analgesics may help improve ventilation by decreasing pain during breathing, but ventilation may need to be supported mechanically. Volume status should be closely monitored because harm can result from either hypovolemia (due to lung hypoperfusion) or hypervolemia (due to pulmonary edema). In select patients with flail chest (patients who cannot be weaned from the ventilator or who require thoracotomy for other reasons), operative fixation of ribs may reduce the risk of pneumonia, length of hospital stay, duration of mechanical ventilation, and death (1).

Treatment reference

  • Simon B, Ebert J, Bokhari F, et al: Management of pulmonary contusion and flail chest: An Eastern Association for the Surgery of Trauma practice management guideline. J Trauma and Acute Care Surgery 73(5 Suppl 4):S351-S361, 2012. doi: 10.1097/TA.0b013e31827019fd.

Click here for Patient Education
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
Professionals also read

Also of Interest

Videos

View All
Bridging
Video
Bridging
1. Lie on back with both knees bent and feet on floor/table. 2. Perform abdominal and gluteus...
3D Models
View All
Nerves, Arteries, and Ligaments of the Ankle and Foot
3D Model
Nerves, Arteries, and Ligaments of the Ankle and Foot

SOCIAL MEDIA

iOS Android
iOS Android
iOS Android
TOP