Determining Which Patients Require Evaluation for Blunt Cardiac Injury following Blunt Chest Trauma

Abstract

The objective of this study was to determine prospectively which risk factors require cardiac monitoring for blunt cardiac injury (BCI) following blunt chest trauma. All patients who sustained blunt chest trauma had an electrocardiogram (ECG) on admission to our urban level I trauma center. Those with ST segment changes, dysrhythmias, hemodynamic instability, history of cardiac disease, age > 55 years, or a need for general anesthesia within 24 hours (group 1) were admitted to the intensive care unit (ICU) for 24 hours where they were subjected to serial ECGs, creatinine phosphokinase (CPK) assays, and echocardiography (ECHO). Those with only mechanism for BCI, i.e., none of the above risk factors (group 2), were admitted to a nonmonitored bed and had a follow-up ECG 24 hours later. A series of 315 patients were admitted with blunt chest trauma during a 17-month period; 144 patients were in group 1 and 171 in group 2. Overall, 22 patients were diagnosed as BCI (+BCI), defined as evolving ST segment changes, dysrhythmias, a CPK-MB index of > 2.5, or hemodynamic instability. Of the 18 +BCI patients in group 1, all were symptomatic (i.e., none was included solely for a cardiac history, age, or need for general anesthesia). Six of these patients required treatment for dysrhythmias, hypotension, or pulmonary edema; one of whom died. Four patients with +BCI were in group 2 and had ECG changes at 24 hours; none of these four had any sequelae from their +BCI. None of the ECHOs demonstrated abnormal wall motion. Patients who sustain blunt chest trauma with a normal ECG, normal blood pressure, and no dysrhythmias on admission require no further intervention for BCI. Patients with ST segment changes, dysrhythmias, or hypotension following blunt chest trauma should be monitored for 24 hours, as this subgroup occasionally requires further treatment for complications of BCI. ECHO adds nothing as a screening test.

Transient electrocardiographic abnormalities following blunt chest trauma in a child

“…We hypothesize that the quantity of damaged myocardial cells was not sufficient to increase the circulating levels of troponin T above the clinical detection threshold, or cause echocardiographic features of cardiac injury. This hypothesis is supported by three facts: (1) the myocardial wall architecture of the RV is thinner than the left ventricle (LV) [5,11], (2) several studies have shown that the RV is more frequently injured than the LV in patients with BCI following blunt chest trauma because of the anterior position of the RV in the thorax and its proximity to the sternum [5,10,11], and (3) the impact of the blow to the chest did not cause overwhelming cardiac injury, although a sternal fracture was present.…”

“…ECG abnormalities are frequently demonstrated in patients following blunt chest trauma and can be nonspecific [1,6,9,[10][11][12]. Some of the ECG abnormalities can be mediated by noncardiac factors such as hypoxia, anemia, serum electrolyte disturbances, or changes in vagal or sympathetic tone, particularly in multi-trauma patients [11].…”

“…BCI frequently occurs in nonpenetrating chest trauma and its manifestations include a wide spectrum of cardiac complications [1,6,7,9,[10][11][12]. Most patients have mild or moderate BCI.…”

“…BCI, or cardiac contusion, is a diagnostic challenge because of nonspecific symptoms and lack of an ideal diagnostic tool. BCI encompasses a wide spectrum of cardiac injury with varied severity and clinical presentation [10][11][12]. Recognition of BCI is crucial, as it may cause life-threatening arrhythmias or heart failure [11,12].…”

Challenges in the diagnosis of blunt cardiac injuries

“…Abnormalities such as wall motion defects and valvular incompetence are readily recognised. Nagy et al [52] in a prospective analysis of 315 patients, ascertained that the echocardiogram has no added diagnostic utility for patients with normal ECG and blood pressure on admission. Also, the Eastern Association for the Surgery of Trauma recommends selective use of echocardiography for patients, who are haemodynamically unstable or suffer cardiac complications [33].…”