1. 2003-3-31Trauma M&M Conference1 Blunt Thoracic Injury - blunt cardiac injury and others- Chao-Wen Chen M.D. Division of Surgical Emergency and Trauma, Department of Emergency, KMUH

2. 2003-3-31Trauma M&M Conference2 PrefacePreface  2/3 of victims of major blunt trauma suffer from thoracic injury.  Thoracic injury account for 20-25% of deaths due to trauma.  Major thoracic trauma is associated with multisystem injuries in 70% of cases.

3. 2003-3-31Trauma M&M Conference3 Common Injuries Develop After Blunt Chest Trauma  Thoracic cage fractures  Lung contusion and tears  Myocardium contusion  Aortic rupture

4. 2003-3-31Trauma M&M Conference4 Initial Survey  Assume the existence of C-spine injury  ABCs  Gerneral evaluation: PE, PH, ECG, or ABG …  Chest x-ray  Administer oxygen

5. 2003-3-31Trauma M&M Conference5 Imaging Survey  Chest x-ray  Chest x-ray : serve as a screening rather than a definite test  repeat radiography should be ordered if suspicious  Computed tomography  Computed tomography : highly sensitive in detecting injuries and superior to routine chest x-ray  recommended in patients with multiple trauma and suspected chest trauma  Angiogram  Angiogram : for suspicious great vessel injuries  Chest ultrasound  Chest ultrasound : detect hemothorax, FAST

6. 2003-3-31Trauma M&M Conference6 Troublesome Injuries  Sternal fracture More serious injuries may accompany If suspected, a lateral CxR may be diagnostic Operative reduction is usually unnecessary Hospitalization is not mandatory if the ECG is normal and the patient ’ s vital sign is stable

7. 2003-3-31Trauma M&M Conference7 Associated Literature chest x-ray and ECG did not reveal any significant findingscardiac echocardiography chest CT  a 38-year-old female patient transferred to our hospital after being injured in a MVA … On arrival her blood pressure (BP) was 90/50 mmHg but it then dropped to 60/30 mmHg two hours later ….her chest x-ray and ECG did not reveal any significant findings, the cardiac echocardiography was performed and revealed pericardial effusion. The chest CT revealed sternal fracture and cardiac tamponade … A diagnosis of cardiac rupture resulting from sternal fracture following blunt chest trauma was made. Under midline sternotomy, her right atrial rupture was repaired. …. “ Traumatic cardiac injury following sternal fracture: a case report and literature review ” Kaohsiung Journal of Medical Sciences. 18(7):363-7, 2002 Jul.

8. 2003-3-31Trauma M&M Conference8 Troublesome Injuries  Flail chest Fracture of 2 or more consecutive ribs in at least 2 places each About 30-40% of patients need mechanical ventilation ARDS is increased 20-30% in the presence of flail chest

9. 2003-3-31Trauma M&M Conference9 Troublesome Injuries  Flail chest Close monitoring of respiratory performance Adequate analgesic therapy Provide oxygen therapy and ventilatory support Aggressive pulmonary toilet

10. 2003-3-31Trauma M&M Conference10 Troublesome Injuries  Lung contusion CxR finding may range from minimal interstitial infiltrate to extensive lobar consolidation Chest CT is accurate diagnostic tool but not always mandatory same as flail chest Tx : same as flail chest, but pay attention to avoid overhydration; use of steroid and prophylactic antibiotic are still controversial

11. 2003-3-31Trauma M&M Conference11 Troublesome Injuries  Blunt Cardiac Trauma - spectrum Asymptomatic myocardiac contusion Symptomatic myocardiac contusion Free wall or septal wall rupture Valvular tears Coronary artery thrombosis

12. 2003-3-31Trauma M&M Conference12 Troublesome Injuries  Blunt Cardiac Trauma – risk factors Chest impact > 15 mph Marked precordial tenderness, ecchymosis or contusion PH of cardiac disease Fractured sternum Thoracic spine or ribs fractures Hemodynamic instability, or multiple injuries Age > 50

13. 2003-3-31Trauma M&M Conference13 Troublesome Injuries  Blunt Cardiac Trauma - assessment Most are asymptomatic; severe cases die before arrival Common manifestation : arrhythmia, hemo- dynamic instability Evaluation : CxR, ECG, cardiac enzymes, echo- cardigram, MUGA

14. 2003-3-31Trauma M&M Conference14 Associated literature Measurement of cTnl accurately detects cardiac injury in patients with blunt chest trauma  The ratio of MBCK to total creatine kinase improved specificity at the expense of sensitivity. Measurement of cTnl accurately detects cardiac injury in patients with blunt chest trauma and should facilitate the diagnosis and management of such patients … “ Improved detection of cardiac contusion with cardiac troponin I. ” American Heart Journal. 131(2):308-12, 1996 Feb

15. 2003-3-31Trauma M&M Conference15 Associated literature ECG and TnI  The combination of normal ECG and TnI at admission and 8 hours later rules out the diagnosis of SigBCI. In the absence of other reasons for hospitalization, such patients can be safely discharged … “ Normal electrocardiography and serum troponin I levels preclude the presence of clinically significant blunt cardiac injury ” Journal of Trauma-Injury Infection & Critical Care. 54(1):45-50; discussion 50-1, 2003 Jan.

16. 2003-3-31Trauma M&M Conference16 Associated Literature  Heat shock protein (HSP)  Heat shock protein (HSP) synthesis arises transiently as a tool to protect cellular homeostasis after exposure to heat and a wide spectrum of stressful and potentially deleterious stimuli … “ Normal electrocardiography and serum troponin I levels preclude the presence of clinically significant blunt cardiac injury ” Journal of trauma-injury infection & critical care. 54(1):45-50; Discussion 50-1, 2003 Jan.

17. 2003-3-31Trauma M&M Conference17 Troublesome Injuries  Blunt cardiac trauma - management Most cases do not require Tx; Symptomatic arrhythmia (2-5%)  antiarrthythmics Abnormal ECG and cardiac enzymes almost return to normal within one week. Patients with abnormal cardiac echo finding or MUGA  keep hospitalization till a repeat test show acceptable finding Cardiac rupture  prompt surgical repair

18. 2003-3-31Trauma M&M Conference18 Troublesome Injuries  Blunt cardiac trauma - Guideline (USC+LAC) TnT Obtain admission ECG and CPK-MB/TnT in patient with suspect BCI Repeat ECG 8-12 hours after admission For unexplained hemodynamic instability, abnormal ECG, and abnormal cardiac enzyme levels  perform cardiac echogram If no suspect symptomatolgy, lab tests or ECG finding  discharge after 12 hours

19. 2003-3-31Trauma M&M Conference19 PitfallsPitfalls  Ignore the presence of blunt cardiac injury in patients with blunt thoracic injury  Failure to recognize the blunt cardiac injury as the reason of hemodynamic instability in the absence of bleeding

20. 2003-3-31Trauma M&M Conference20 Thank you for your attention!