What precautions should be taken in a patient with a history of trauma and a sternal body fracture, particularly with regards to potential associated injuries and complications?

Precautions with Sternal Body Fracture

Immediate Cardiac Evaluation is Mandatory

All patients with sternal fractures require immediate ECG and cardiac troponin levels to detect myocardial contusion and malignant ventricular arrhythmias, regardless of whether the fracture appears isolated. 1, 2

Critical Initial Assessment

• Obtain 12-lead ECG immediately upon presentation, as 6% of patients with sternal fractures develop arrhythmias and myocardial contusion even when the fracture appears isolated 1
• Draw cardiac troponin levels at presentation, as rising troponins combined with ECG changes indicate myocardial injury requiring cardiac monitoring 1, 2
• Assess hemodynamic stability first before proceeding with imaging, as this determines the entire diagnostic pathway 3

Risk Stratification Based on Cardiac Workup

Patients with normal ECG and normal cardiac troponin levels are low probability for significant cardiac injury and can be safely discharged with appropriate pain management and outpatient follow-up 2, 3

Patients with abnormal ECG findings or rising troponin levels require hospital admission for cardiac monitoring, as they are at risk for malignant arrhythmias and myocardial contusion 1, 2

Imaging Strategy

CT Chest Protocol

• Obtain CT chest without IV contrast using sagittal and 3-D reconstructions to accurately detect sternal fracture displacement and identify hemothorax or hemopericardium by measuring attenuation 1, 2
• Add IV contrast if hemothorax or hemopericardium is detected, as this identifies the source of bleeding and evaluates for concomitant cardiovascular injury 1

When to Skip Echocardiography

Do not order echocardiography for isolated sternal fractures when ECG and cardiac troponins are normal, as this adds no diagnostic value 1, 2

Reserve echocardiography for patients with abnormal ECG, elevated troponins, signs of heart failure, or abnormal heart sounds 2, 3

Screen for High-Risk Associated Injuries

Cardiac Complications (Most Life-Threatening)

• The right ventricle is most commonly injured due to its anterior location, followed by left ventricle and right atrium 1, 2
• Hemopericardium with cardiac tamponade can occur when pericardium remains intact and hemorrhage accumulates, requiring immediate intervention 1, 2
• Look for the triad of high-attenuation pericardial effusion, peri-portal low attenuation, and distention of the IVC/renal/SVC/azygos veins on CT, which indicates cardiac tamponade 1

Thoracic Injuries

• Rib fractures occur in 30% of patients with sternal fractures and are the most common associated injury 4
• Pulmonary contusion and pneumothorax require evaluation, particularly in high-energy mechanisms 5
• Pericardial rupture with heart herniation is rare but catastrophic—look for empty pericardial sac, "collar sign" (constriction of cardiac contour), and malposition of heart to left or right hemithorax 1

Other Associated Injuries

• Extremity fractures occur in 18% of patients and should be systematically evaluated 4
• Intrathoracic and intraabdominal injuries are common in polytrauma patients with sternal fractures 5

Pain Management Protocol

Start with regular acetaminophen (paracetamol) unless contraindicated, and add opioids as needed for adequate pain control before diagnostic investigations 2

Avoid NSAIDs if renal function has not been assessed, as approximately 40% of trauma patients have moderate renal dysfunction and NSAIDs are relatively contraindicated 2

Document pain scores at rest and with movement before and after analgesia administration to guide therapy 2

Admission Criteria

Admit to Hospital If:

• Abnormal ECG or elevated/rising cardiac troponins (requires telemetry monitoring) 1, 2
• Hemodynamically unstable or signs of cardiac tamponade 3
• Severely displaced fractures or complex comorbidities 6
• Significant associated injuries requiring intervention 4, 6
• Inadequate pain control with oral medications or complex analgesic requirements 6

Safe for Discharge If:

• Normal ECG and normal cardiac troponins 2, 3
• Hemodynamically stable 6
• Pain adequately controlled with oral medications 2, 6
• No significant associated injuries 4, 6
• Reliable outpatient follow-up arranged 6

Conservative Management for Isolated Fractures

88% of patients with sternal fractures do not require parenteral analgesia or procedures necessitating admission, and isolated sternal fractures are benign entities managed with rest and analgesia 6

Begin early mobilization as pain allows, typically within 24-48 hours, as this improves respiratory mechanics and prevents complications 2

Consider calcium (1000-1200 mg/day) and vitamin D (800 IU/day) supplementation in elderly patients to address underlying osteoporosis 2

Common Pitfalls to Avoid

• Do not assume isolated sternal fracture is benign without cardiac evaluation—6% develop arrhythmias and myocardial contusion even when fracture appears isolated 1
• Do not rely on chest X-ray alone—misdiagnosis rate is 5.5% compared to CT 5
• Do not attribute tachycardia solely to pain—it may represent cardiac tamponade, ongoing hemorrhage, or blunt cardiac injury 3
• Do not discharge patients with abnormal ECG or elevated troponins—they require cardiac monitoring even if hemodynamically stable 1, 2

VTE Prophylaxis

Consider pharmacologic VTE prophylaxis with LDUH or LMWH in major trauma patients unless contraindicated by bleeding risk 1

Add mechanical prophylaxis with IPC when pharmacologic prophylaxis is contraindicated by lower-extremity injury 1