Flail Chest: Pathophysiology and Trauma

• Flail chest results from trauma to the thorax, with three or more ribs broken in at least two places.
• The broken rib segments move independently, disturbing chest wall stability.

Pathophysiology

• The chest wall moves inward during inspiration while the rest of the thorax expands outward.
• Severity depends on pleural pressure, the extent of the flail, and intercostal muscle movement during inspiration.
• Flail chest affects respiration through ineffective ventilation, hypoventilation with atelectasis, and pulmonary contusion.
• Ineffective ventilation occurs due to increased dead space, decreased intrathoracic pressure, and increased oxygen demand.
• Associated trauma leads to pulmonary contusion with edema and hemorrhage, reducing lung space and impairing gas exchange.
• Pain from the injury leads to hypoventilation, atelectasis, and reduced inspiratory effort, potentially collapsing lung tissues.
• Compromised rib cage causes the affected chest area to move inward on inspiration due to negative chest cavity pressure, leading to paradoxical movement.
• The non-fractured side expands during inspiration, while the injured side sinks inward, causing inadequate oxygenation in the affected lung area.
• Tachypnea and decreased oxygen saturations result, leading to tachycardia as the heart compensates for decreased oxygen levels.

Risk Factors and Long-Term Effects

• Flail chest is commonly caused by blunt trauma, such as from motor vehicle collisions (75%) and falls (15%).
• Direct blows to the chest, such as assaults or motorcycle ejections, can also cause flail chest.
• High pain levels are experienced with each respiratory cycle, and resultant splinting alters gas exchange.
• Pain control and education are essential to reduce complications like atelectasis.
• Long-term effects include persistent pain, dyspnea, exercise intolerance, and permanent chest wall deformity.

Special Considerations

• Older adults (over 65) with stiffened thorax and higher osteoporosis rates are at increased risk of flail chest and complications.
• Older adults or those with respiratory disease have a decreased ability to compensate for gas exchange alterations, increasing the risk of respiratory distress or failure.

Assessment Findings

• Clients with a flail chest usually present in the ED due to a traumatic event.
• Symptoms include severe chest wall pain, tachypnea, splinting, and respiratory insufficiency.
• Bruising or bleeding may be present on the chest.
• The flail segment pulls inward during inspiration and pushes outward during expiration.

Diagnostic Evaluation

• Chest x-rays have low sensitivity and may miss rib fractures.
• CT scans are the preferred diagnostic study for evaluating flail chest and related injuries.
• Diagnosis requires clinical correlation with the finding of three or more adjacent ribs broken in two or more places on x-ray or CT.
• Arterial blood gases (ABGs) assess manifestations of respiratory failure.
• pH is usually high (alkalotic) due to low PaCO2.
• Bicarbonate is low due to compensation for low PaCO2.
• PaO2 is low due to respiratory distress and decreased gas exchange.

Nursing Interventions

• Focus on managing the ABCs (airway, breathing, circulation).
• Coordinate with pain management or anesthesiology to address pain.
• Monitor for complications related to flail chest and implement prophylactic measures for DVT or stress ulcers.
• A primary survey should be done initially, then move on to the secondary survey, which includes airway, breathing, circulation, disability, and exposure (ABCDE).
• Assess respiratory status, noting respiratory distress, rate, effort, oxygen saturation, chest expansion, and airway.
• Vital signs should be checked to evaluate hemodynamic stability.
• Examine the chest for signs of trauma (bruising, bleeding, open wounds, paradoxical wall movement).
• Auscultate lung sounds bilaterally and palpate for tenderness, abnormalities, or crepitus.
• Assess neurological status using the Glasgow Coma Scale.
• Complete a head-to-toe assessment and obtain a history of the injury.
• Assess pain using a standardized pain scale.
• Monitor ventilator settings and modes if intubation is required.
• Assess and monitor the tube for secure positioning and proper placement.
• Note the client’s age and review the electronic health record for underlying conditions that may further impair pulmonary function.

Collaborative Problems

• Respiratory distress, such as tachypnea, cyanosis, and hypoxia.
• Hemodynamic instability, such as hypotension.
• Contusions, bruising, or open wounds on the chest or chest wall abnormalities, along with paradoxical chest movement.
• Unilateral paradoxical chest movement indicates chest instability due to multiple rib fractures and respiratory insufficiency.
• Splinting during respirations can also add to respiratory insufficiency.

Expected and Unexpected Findings

• Expected: pain, bruising, tachypnea, decreased O2 saturation, paradoxical chest movement, splinting with breathing.
• Unexpected: respiratory distress, cardiac arrest, hypotension, hypoxia, change in cognition, abnormal ABGs, abnormal cardiac enzymes.

Client Outcomes

• Restoration or maintenance of adequate respiratory effort and oxygenation, evidenced by an oxygen saturation of 95% or greater on room air.
• Monitor ventilator settings and check tube placement frequently for intubated clients.
• Adequate pulmonary toileting to clear secretions and prevent complications like pneumonia.
• Educate the client on coughing, deep breathing, use of the incentive spirometer, and early ambulation to facilitate respiratory effort and prevent complications.

Management

• Elevate the head of the bed, administer oxygen, and consider noninvasive ventilation (CPAP) as the client’s condition warrants.
• If the client has significant respiratory compromise or all other treatment options fail, assist in preparing the client for intubation and mechanical ventilation.
• Monitor the endotracheal tube placement and provide suctioning as needed.
• Work closely with the respiratory therapist to manage ventilator settings.
• For clients receiving mechanical ventilation, decrease iatrogenic risks, such as VAP, by performing range-of-motion exercises and repositioning the client to prevent muscle disuse
• Provide appropriate nutrition to avoid tissue wasting. Enforce preventive measures, such as elevating the head of the bed. Oral hygiene and PROM exercises.
• Spontaneous breathing trials and sedation holidays or vacations are preformed to facilitate weaning as early as possible.

Pain Management

• Includes administering pain medications as ordered to relieve chest pain due to the fractured ribs.
• Education includes coughing, deep breathing, and the use of the incentive spirometer.
• Frequent assessment of the client’s respiratory status and vitals will allow the nurse to evaluate the efficacy of the nursing actions and determine if the expected outcomes were met.

Interventions

• Should progress from least invasive to invasive to ensure the highest level of safety.
• CPAP and the use of a mechanical ventilator cause pressure changes in the chest cavity and decrease the paradoxical movement of the chest wall.
• Surgical repair of the ribs involves using fixation devices, such as wires, struts, and mesh.
• Maintaining ventilation should initially be achieved using an oxygen delivery device, such as a nasal cannula or face mask.
• Types of NIV include hi-flow nasal oxygen, continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP).
• Fluids should be administered via IV, and pain management must be addressed early with opioids, nerve blocks, or epidural anesthesia.
• Surgery may be necessary to stabilize the fractured ribs using wire or mesh or may be considered for clients who are unable to wean off mechanical ventilation and the respiratory decline continues.

Flail chest results from trauma, causing unstable chest wall movement due to multiple rib fractures. This condition leads to ineffective ventilation, hypoventilation, and pulmonary contusion. Pain and associated trauma further impair gas exchange and lung function, increasing oxygen demand and potentially causing lung collapse.