Dr.Kasturi Bhagawati Emergency Medicine Department

Transcription

1 Dr.Kasturi Bhagawati Emergency Medicine Department

2 Introduction Chest trauma is often sudden and dramatic. Cardiac injuries can be catastrophic. Accounts for 25% of all trauma deaths 10% of deaths of gunshot wound Suspect in cases associated with injury to chest,lower neck,epigastric or precordial injury.

3 Types of injuries Penetrating gun,knives,rods,glass. Blunt MVA,blast,crush,deceleration,torsion,direct precordial impact. Iatrogenic Ryles tube,central line,chest tube.

4 Mechanism of Injury Penetrating injuries Cardiac tamponade Haemothorax Pneumothorax Cardiac, great vessel or oesophageal injury ¾ of penetrating cardiac injuries may die before medical care. 2/3 of deaths occur after reaching hospital.

5 Blunt injuries Either: direct blow (e.g. rib fracture) deceleration injury or compression injury Rib fracture is the most common sign of blunt thoracic trauma Fracture of scapula, sternum, or first rib suggests massive force of injury

6 The primary survey life threatening conditions are identified and ATLS principle is begun simultaneously! A Airway maintenance with cervical spine immobilization. B Breathing and ventilation C Circulation with hemorrhage control D Disability: neurological status E Exposure: completely undress the patient

7 Clinical indicators Physiological Increasing respiratory rate Increasing pulse rate Falling blood pressure Rising serum lactate Anatomical Visible bleeding Injury in close proximity to major vessels Penetrating injury with retained weapon

8 Immediately life threatening Airway obstruction Tension pneumothorax Pericardial tamponade Open pneumothorax Massive haemothorax Flail chest

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10 Potentially life threatening Aortic injuries Tracheobronchial injuries Myocardial contusion Rupture of diaphragm Oesophageal injuries Pulmonary contusion pneumomediastinum

11 Spectrum of injuries. Cardiac wall Chordae tendinae Papillary muscles Atria RA(20%),LA(5%) Ventricle RV(40%),LV(35%) Septum Coronary arteries Conducting system Valvular aortic,mitral,tricuspid

12 Pathological changes of blunt injury Subendocardial haemorrhage Focal myocardial edema Interstitial haemorrhage Myocytolysis Coronary artery spasm Coronary artery dissection Compression from adjacent haemorrhage Redistribution of coronary blood flow

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14 Associated injuries Rib fracture Aortic/great vessel injury Hemothorax Pulmonary contusion Pneumothorax Sternal fracture Diaphramatic injury. Head injury Extremity injuries Spinal injuries Abdominal injuries

15 Cause of death At the scene Complex arrhythmias Cardiac free wall rupture Laceration of coronary artery extracardiac haemorrhage. At hospital Low pressure chamber/injury to coronary vein Rupture of atrial/venticular septum Papillary muscle rupture Acute heart failure Valvular regurgitation.

16 Blunt cardiac injury Myocardial contusion ventricular, septal or valvular rupture Cardiac tamponade Ruptured thoracic aorta Pericardial injury

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19 Incidence According to CDC 30,000 cases /year Due to lack of standard diagnostic criteria incidence of blunt cardiac injuries remain uncertain. Range from benign myocardial contusion to fatal chamber rupture. High incidence of left sided valvular injury in severe thoracic injury

20 ECG changes MI changes Multiple PVC s Sinus tachycardia Atrial fibrillation Bundle branch block.

21 Investigations Cardiac markers CKMB,Troponin I &T Sensitivity of toponin (12 23)% Specificity of troponin (97 100)% Echocardiography

22 Commotio cordis Sudden death due to blunt trauma chest. 2 nd cause of death in young athletics Cause blow 10 30msec before peak of T wave Depends on hardness of object,location of impact,velocity,sports Autopsy findings normal cardiac anatomy Risk ventricular fibrillation

23 Myocardial contusion Reported in 3% 55% of cases. Most common cause is high speed deceleration injuries MVA without evidence of chest trauma. Mechanism direct blow to chest increased intrathoracic pressure. sudden deceleration displacement of abdominal viscera upward.

24 Pathophysiology Microcellular damage mild disruption of myofibrils complete loss of structure necrosis & polymorphonuclear infiltration of area as seen in ischemic MI. Accumulation of edema & cellular infiltrates in the wall of heart decrease in ventricular compliance cardiac dysfunction.

25 Vascular damage occurs in capillaries. Acute thrombus formation occurs in diseased atheromatous vessels cononary occlusion & MI. Arterial spasm,intimal tear or compression from adjacent haemorrhage & edema. Most heals spontaneouslywith resolution of cellular infiltrate & haemorrhage scar formation.

26 Necrosis in 2 nd week rupture of septum,papillary muscles or free ventricular wall.cause of sudden death. Small pericardial effusion occurs in 50% cases 2 weeks. A fibrinous reaction at contusion site may occur pain,friction rub & adhesion to pericardium.

27 diagnosis Sinus tachycardia,rbbb,cardiogenic shock Ecg ST T changes,av block,svt,ventricular /atrial extrasystole. Less common VT,AF,VF Troponin I & T, CKMB 2D echo Angiography Thallium 201 myocardial scintigraphy.

28 Treatment PCI Dobutamine IABP Contraindication thrombolysis,aspirin.

29 Myocardial rupture. Atria > ventricle Acute traumatic perforation,pericardial rupture,laceration,rupture of interventricular septum. Delayed rupture may occur after weeks of trauma. Necrosis of a contused or infarcted area of myocardium. 1/3 multiple chamber rupture,1/4 associated with aortic rupture.

30 Cont. Physical examination splashing mill wheel sounding murmer.(bruit de Moulin) Ecg conduction defects (AV block,fascicular block,rbbb), axis deviation.

31 Cardiac Tamponade Blood in the pericardial sac Most frequently penetrating injuries Shock, JVP, pulsus paradoxus Classically, Beck s triad: distended neck veins muffled heart sounds hypotension Echo reveals diastolic collapse of RA or RV wall, a sign pathognomonic for cardiac tamponade. Rx Pericardiocentesis

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40 Illustration of leftward septal shift with encroachment of left ventricular volume during inspiration in cardiac tamponade

41 Normal 2D ECHO 1/19/

42 Normal 2D ECHO 1/19/

43 Normal 2D ECHO 1/19/

44 example 1/19/

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47 Respiration marker and aortic and right ventricular pressure tracings in cardiac tamponade paradoxical pulse and marked, 180 degrees out of phase respiratory variation in right and left sided pressures

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49 Pericardial injuries Pericardial rub Pneumopericardium ST elevation J waves Straight left cardiac border Globular heart. No fluid,usg is of no use

50 Great vessel injury Aorta Brachiocephalic Pulmonary vessels SVC Innominate vein Azygous vein

51 Traumatic aortic injury Most common vessel to be injured. Mortality 15% (MVA) 10 20% survive temporarily to reach hospital. Males > females 85% survive with prompt diagnosis & surgical intervention. 90% tear occurs in descending aorta at isthmus distal to left subclavian artery.

52 Other sites Ascending aorta (70 80%) Descending aorta at level of diaphragm Midthoracic descending aorta Origin of left subclavian artery.

53 Clinical sign. Traumatic aortic rupture interscapular /retrosternal pain. Dyspnea Stridor/hoarseness Extremity pain. Reflex Hypertension Harsh systolic murmur Swelling over neck,pulsatile

54 Diagnosis Mediastinal widening chest x ray. Ct sign aortic pseudoaneurysm, periaortic hemorrhage, rt displacement of trachea & esophagus Intimal flap project into lumen, coarctation, small aortic caliber in lower chest, peridiaphragmatic hemorrhage, luminal clot at site of intimal disruption.helical CT is 100% sensitivity & specificity Echography TEE blurring of aortic outline, intraluminal artifacts.sensitivity 87% 100%,specificity 98% 100% Aortography

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56 Due to delayed hypersensitivity reaction to damaged myocardium. Clinical feature Retrosternal pain - radiating to shoulders & neck, aggravated by deep breathing / movement / change of posture / exercise / swallowing etc. Low grade fever Pericardial friction rub - superficial scratchy or crunching noise with to-and-fro quality

57 Acute pericarditis is characterized by 2 injury currents

58 Acute pericarditis Diffuse ST segment elevation with PR segment depression

59 Aortic rupture Usually blunt trauma involving deceleration forces; especially RTAs ~90% die within minutes Most common site near ligamentum arteriosum Dx: clinical suspicion, CXR, aortography, contrast CT Rx: surgical poor prognosis

60 Aortic rupture

61 Valvular injury. 10% of blunt cardiac injury. Aortic valve > mitral > tricuspid Injury to aortic valve cause severe regurgitation Pulmonary edema. MV & TV injuries associated with pericardial laceration. Valvular rupture may involve chordae tendinae,leaflets or papillary muscles.

62 Findings Acute mitral regurgitation loud,harsh diastolic murmur, left heart failure. Tricuspid insufficiency diastolic murmer,prominent V wave of JVP. Isolated septal defect exertional dyspnea,pulmonary edema. VSD holosystolic murmur along left sternal border.

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64 Pitfall Ignore the presence of blunt cardiac injury in patient with thoracic injury Failure to recognize the blunt cardiac injury as the reason of hemodynamic instability in absence of bleeding.

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