Circulating cardiac troponin I in trauma patients without cardiac contusion

Objectives: To describe the evolution and the diagnostic value of cardiac troponin I (cTnI) and to relate its concentrations with the indicators of injury in trauma patients. Design: Prospective, observational study of 17 young, previously healthy, mechanically-ventilated patients during the early post-traumatic period in the Surgical ICU of a University Hospital. Methods: Serial measurements of serum cTnI, total creatine kinase activity (CKtot) and its isoenzyme MB (CK-MB) (on admission, 12 h later, then daily for 7 days), clinical data and repeated electrocardiographic (ECG) and transesophageal echocardiographic (TEE) recordings. Results: Rhabdomyolysis was observed in all the patients with a significant relationship between CK-MB and CKtot. Despite the fact that no patient demonstrated ECG or TEE signs of myocardial contusion, elevated serum levels of cTnI were observed in six patients (35 %) without obvious dilutional interference. As compared with the others, these patients exhibited a more frequent arterial hypotension (83 % vs 18 %, p = 0.035), required greater volume expansion on day 1 (22,000 vs 8,500 ml, p = 0.027) and usually demonstrated early (83 % vs 9 %, p = 0.005) and late (66 % vs 9 %, p = 0.028) multiple organ dysfunction syndrome. Conclusions: Taking into account the high reported sensitivity and specificity of cTnI dosage, the present results suggest cTnI can play a role in the evaluation of indirect myocardial injury following traumatic shock. Received: 20 November 1997 Accepted: 3 March 1998