1. EDT DR MAJIDI EMR

2. INDICATIONS AND CONTRAINDICATIONS 1. Chest Injuries (General) 2.Cardiac Injuries-Penetrating 3.Pulmonary Injuries 4.Cardiac Injuries-Blunt 5.Air Embolism 6.Major Vascular Injuries 7.Blunt and Penetrating Abdominal Injur 8.Open-Chest Resuscitation for Nontraumatic Arrest

3. Chest Injuries (General) The indications for EDT gradually expanded to include extrathoracic as well as blunt trauma. As a result, the overall survival rate became quite poor, fueling controversy over the indications for EDT.

4. CONT The first decision point in determining which patients may benefit from an EDT is the paramedic's initial contact with the patient. Important information in formulating a decision to perform an EDT includes the mechanism of injury, site of major injury and the time of injury, EMS arrival, and, when relevant, the time vital signs or cardiac electrical activity or both ceased.

5. CONT An analysis of prehospital time in patients with penetrating chest trauma receiving EDT demonstrated that when times exceeded 30 minutes, no patient survived to be transferred out of the ED following EDT. For the patients with a prehospital time of less than 30 minutes, 63% were alive in the ED, although all patients subsequently died.

6. CONT The type of electrical activity in conjunction with mechanism of injury is helpful in determining who may benefit from EDT. Asystole in the face of blunt trauma without vital signs in the field should be considered an absolute contraindication to EDT.

7. CONT patients with a mechanism of penetrating torso injury with asystole as the presenting rhythm should still be considered as candidates for EDT.

8. Cardiac Injuries-Penetrating Those patients with vital signs following penetrating cardiac injury will present with symptoms consistent with pericardial tamponade or shock Tamponade may occur if the wound is less than I cm in siz (dependent on the chamber involved) while wounds greater than 1cm usually continue to bleed regardless of the chamber involved.

9. CONT Cardiac tamponade is the decompensated phase of cardiac function resulting from increased intrapericardial pressure The progression from compensated cardiac function to uncompensated tamponade can be sudden and profound.

10. CONT Although one may suspect tamponade based on well-described signs, the clinical diagnosis of pericardial tamponade in the unstable trauma patient is made difficult because of the combined effect of hemorrhagic and cardiogenic shock.

11. CONT The classic signs of Beck triad (distended neck veins, hypotension, and decreased heart sounds) have limited diagnostic value for acute penetrating cardiac trauma.

12. Cardiac Injuries-Blunt Blunt trauma to the heart ranges from minor contusion to frank cardiac rupture. Blunt cardiac rupture accounts for 5% of motor vehicle fatalities. Survivors had vital signs in the field. The poor outcome associated with this type of injury

13. Pulmonary Injuries Pulmonary injuries can be divided into three types: 1) parenchymal,2) tracheobronchial, and 3)large-vessel Parenchymal and tracheobronchial injuries rarely require EDT. Most of these injuries are either rapidly fatal or can be adequately treated initially by tube thoracostomy.

14. CONT Tracheobronchial injury is more common with blunt than penetrating trauma and most patients with this injury die at the scene. Ninety percent of tracheobronchial tears occur within 3 cm of the carina and most commonly involve the main stem bronchi.

15. CONT Massive subcutaneous emphysema and pneumomediastinum are usually seen, although up to 10% of patients with this injury initially will have no x-ray findings. If hemorrhaging is profuse, or if the site of injury can be determined, the use of a bifid endotracheal tube or the unilateral intubation of a main stem bronchus will secure the airway.

16. Air Embolism Air embolism is a complication of pulmonary parenchymal injuries that requires immediate thoracotomy if there is hemodynamic instability. Air embolism may appear in either the right or the left side of the circulatory system. Involvement of the right side of the circulation is referred to as venous or pulmonal}' air embolism.

17. CONT Generally, venous air is well tolerated, but death may occur when the volume of air reaches 5 to 8 mL/kg.

18. CONT Air embolism involving the left side of the circulatory system is referred to as arterial or systemic air embolism The lethal volume depends on the organs to which it is distributed. As little as 0.5 mL of air in the left anterior descending coronary artery has led to ventricular fibrillation.

19. CONT Two milliliters of air injected into the cerebral circulation can be fatal. The diagnosis of air embolism is easily overlooked because of the similarity of the signs an symptoms to those of hypovolemic shock. Two valuable signs that were present in 36% of patients were hemoptysis and the occurrence of cardiac arrest after intubation and ventilation.

20. CONT Focal neurological changes, seizures, and other central nervous system dysfunction in the absence of head injury are also suggestive.

21. Management air emboly A high index of suspicion with rapid control of the source of air embolism is essential. The patient should immediately be placed in the Trendelenburg (head-down) position to minimize cerebral involvement by directing the air emboli to less critical organs.

22. CONT Consideration may be given to isolating the injured lung if unilateral chest injury is present by selective intubation of the contralateral lung. If this step is unsuccessful, the next step should be a left anterolateral thoracotomy.

23. CONT Peripheral bronchovenous fistulas can be identified by the bloody froth created during positive-pressure ventilation. A quick search for hilar injuries should be carried out in the patient with blunt trauma. If the source of air embolism is not readily apparent, a contralateral thoracotomy should be performed.

24. Adjunctive Therap Hyperbaric oxygen therapy is beneficial because it (1) compresses air bubbles; (2) establishes a high diffusion gradient, which greatly speeds the dissolution of the bubbles; (3) improves the oxygenation of ischemic tissues and lowers intracranial pressure; (4) reduces the reperfusion injury that invariably follows the passage of bubbles. When it is available and logistically practical, hyperbaric oxygen therapy should be considered, even though it may be many hours before it can be initiated. Preferentially, treatment is begun within 6 hours of traumatic insult; however, the effectiveness of hyperbaric oxygen therapy is illustrated by cases of success and improvement even when as many as 36 hours elapsed before pressurization.

25. Major Vascular Injuries 90% of major vascular injury is caused by penetrating trauma, 10% by blunt trauma Major vascular injury resulting in rapid deterioration following blunt or penetrating trauma requires the use of an EDT for 1)diagnosis, 2)resuscitation, and 3)control of hemorrhage.

26. Blunt and Penetrating Abdominal Injury In the setting of penetrating abdominal injury, thoracotomy with cross-clamping of the thoracic aorta to control hemorrhage from the injury has been advocated. Because survival rates have been dismal for those undergoing this procedure, it is rarely performed, and its routine use is not recommended.

27. Open-Chest Resuscitation for Nontraumatic Arrest Failure to resuscitate patients from cardiac arrest is a result of (1) a delay in the onset of CPR, (2) the use of less than optimal resuscitative techniques, or (3) the intractability of the underlying disease process

28. CONT The goal of CPR is the restoration of coronary perfusion pressure, which is the prime determinant for return of spontaneous circulation as established in animal models found that a minimal coronary perfusion pressure of 15 mm Hg is required in humans to obtain return of spontaneous circulation

29. CONT Open-chest CPR produced a mean cardiac index of 1.31 Llmin per m2 compared to 0.6 Llmin per m2 during closed- chest CPR. The mean coronary perfusion pressure in the closed-chest group was 7.3 mm Hg versus 32.6 mm Hg in the open-chest group.

30. CONT Neuronal viability appears to be threatened by a cerebral perfusion pressure of less than 30 mm Hg or a cerebral blood flow of less than 15 mLl 100 g per minute. The brain tolerates low flow (5 to 10 mLlI00 g per minute) better than no flow or "trickle" flow (less than 5 mLlIOO g per minute).

31. CONT At present, the precise indication for open- chest resuscitation of nontraumatic arrests is undefined, and the procedure is not considered standard of care. However, in the setting of cardiac arrest from hypothermia, open-chest CPR may be considered.

32. CONT Open thoracotomy with mediastinal irrigation has been used successfully for severe hypothermia with cardiac arrest. With severe hypothermia, ventricular fibrillation is resistant to chemical or electrical conversion, and prolonged periods of closed- chest compression must be provided during the long process of rewarming

33. EQUIPMENT

34. CONT

35. PROCEDURE Preliminary Considerations For all trauma victims presenting to the ED with hypotension, the initial working diagnosis must be volume depletion. Because a large amount of blood may be lost into the chest, an autotransfusion system should be available.

36. Airway Control During Thoracotomy Patients undergoing resuscitative thoracotomy in the ED require assisted ventilation Selective one-lung ventilation using a specialized double-lumen endotracheal tube is an established technique in thoracic surgery, but the availability of and experience with these devices is limited in the ED setting.

37. Anesthesia and Amnesia Comatose patients undergoing resuscitation may regain consciousness during a successful EDT, but the use of paralyzing agents may mask the return of awareness. The clinician must be cognizant of this phenomenon and administer adequate analgesia, amnestic, and muscle relaxing agents tothe ventilated patient. Ketamine (2 mg/kg IV) and midazolam (0.10 to 0.2 mg/kg IV) have been recommended but ideally, agents such as etomidate with minimal effects on cardiovascular performance should be used.

38. Anterolateral Thoracotomy Incision Prior to beginning the procedure, the patient should be intubated and manually ventilated. An assistant may pass a nasogastric tube, which will help differentiate the esophagus from the aorta.

39. POSTION-NG-TRACH TUBE

40. site of injury is unknown When the site of injury is unknown and the patient's status requires immediate intervention for possible intrathoracic injuries, a left anterolateral incision over the fifth rib with dissection into the fourth intercostal space provides the best access to the heart and great vessels.

41. 4 INTERCOSTAL

42. WOMEN

43. 3 INTERCOSTAL In patients with suspected left subclavian vessel injuries or aortic arch injuries, better exposure and control may be obtained through use of the third intercostal space.

44. Exposure The first sweep of the scalpel (No. 20 blade) should separate skin, subcutaneous fat, and the superficial portions of the pectoralis and serratus muscles. It is important to establish wide exposure from the outset by extending the skin incision past the posterior axillary line. To facilitate this action, quickly wedge towels or sheets under the left posterior chest and place the patient's left arm above the head. Inadequate exposure, rib fractures. and additional delays occur when the skin incision is too limited.

45. Entering the pleural cavity After entering the pleural cavity and dividing the intercostals, the next step is to gain good exposure. This is accomplished by placing a chest wall retractor (rib spreader) between the ribs with the handle and ratchet bar directed downward.

46. CONT

47. Just before opening the pleura, ventilations should be stopped momentarily. This will allow the lung to collapse away from the chest wall. To enter the pleural space, a small incision is made in the intercostal muscles and one blade of the scissors is inserted. The intercostal muscles are then cut with the scissors to expose the thoracic cavity.

48. CONT

49. Pericardiotomy If cardiac arrest has occurred, the question of whether to open the pericardial sac arises. If the myocardium cannot be visualized, the pericardium should be opened. However, in some cases, the myocardium can be evaluated through the intact pericardium such as a nontraumatic cardiac arrest. if there is no other obvious injury in the chest and a cardiac injury is possible, the pericardium should be opened routinely, because it may be difficult to definitively rule out pericardial tamponade by visual inspection alone.

50. CONT

51. If the clinician is confident that tamponade is not present, it is usually best to leave the pericardial sac closed while other life-threatening injuries are addressed. Opening the pericardium increases the risk of complications.

52. CONT Pericardiotomy is required if tamponade is present or suspected. With an intact pericardium, pressure is distributed over a larger area and the pericardial fluid seldom allows the compressing fingers to remain in one spot for a prolonged period.

53. Phrenic nerve This is performed in a location anterior and parallel to the left phrenic nerve. The incision begins near the diaphragm to avoid possible injury of the coronary arteries. near diaphragm cephalad Root of the aorta.

54. Direct Cardiac Compressions Three techniques for cardiac compression have been advocated: 1)one-handed compression, 2) one-handed with sternal compression, 3) two-handed (bimanual) compression

55. 1 The one-handed compression method is performed with the thumb placed over the left ventricle, the opposing fingers over the right ventricle, and the apex of the heart resting in the palm of the hand.

56. 2 The one-handed with sternal compression method also is performed with the fingers flat. The fingers of the hand are held tightly together to form a flat surface over the left ventricle while compressing the heart up against the sternum. sternum fingers flat

57. 3 To perform the two-handed compression method, the left hand is cupped and placed over the right ventricle. The fingers of the right hand are held tightly together to fonn a flat surface supporting the left ventricle. This flat surface compresses the heart against the cupped surface of the left hand.

59. Recommend rate A difference of opinion exists regarding the optimal rate at which the heart should be compressed. Most recommend a rate of 50 to 60 compressions per minute;

60. NOTED (1) Fingertip pressure should be avoided at all times. Compression is perfonned using the entire palmar surface of the fingers. (2) Whichever technique is used, the force of compression should be perpendicular to the plane of the septum. The anterior descending coronary artery is located over the interventricular septum and is a helpful landmark to orient proper hand placement. It is clearly seen, with or without the pericardium open. (3) The fingers should be positioned so that the coronary arteries will not be occluded. (4) Venous filling of the heart is especially sensitive to changes in position. It is important to maintain a relatively normal anatomic position of the heart to prevent kinking of the vena cava and pulmonary veins. The heart should not be angled more than 30 degrees into the left chest. (5) It is also essential to completely relax the heart between compressions.

61. Control of Hemorrhagic Cardiac Wounds One may partially control active bleeding from ventricular wounds by placing the finger of one hand over the wound while using the other hand to stabilize the beating heart. This maneuver buys time while the clinician prepares to repair the injury. The use of surgical staples for ventricular wound closure is an extremely rapid method for controlling hemorrhage.

63. Alternatively, the wound can be repaired by placement of several horizontal mattress sutures under the tamponading finger

64. Nonabsorbable 2-0 silk sutures are customarily used. Smaller sutures should not be used, and nylon sutures should be avoided. Some clinicians prefer to use even larger silk sutures, such as No. 1 or 2 (note that this is not the same as 0 [1-0] or 0-0 [2-0] sutures).

65. With large wounds that cannot be palpably controlled, an incomplete horizontal mattress suture should be placed on either side of the wound

66. Inflow occlusion If exsanguinating hemorrhage is not controlled by the aforementioned methods, temporary inflow occlusion can be used. Inflow occlusion may be applied intermittently for 60 to 90 seconds. During occlusion the heart shrinks, hemorrhage is controlled, and sutures can be placed in a decompressed injury. Two techniques that are useful are vascular clamping of the superior and inferior vena cava for partial inflow occlusionand the Sauerbruch grip.

68. Foley catheter Insertion of a Foley catheter (20 Fr with a 30- mL balloon) through a wound is another technique for temporarily controlling hemorrhage. Following insertion of the catheter, the balloon is inflated, the catheter is clamped to prevent air embolism, and gentle traction is applied.

69. It is important to use normal saline when inflating the balloon. Use of air will result in air embolism if the suture needle ruptures the balloon.

70. Wounds of the atria are initially managed with partial occlusion clamps

72. Control of Hemorrhagic Great Vessel Wounds Wounds of the great vessels can be controlled with digital pressure or partial-occlusion clamps. Cross-clamping of the right subclavian artery is very difficult. For injuries of this vessel, compression with laparotomy pads in the apex of the pleura from below, and the supraclavicular fossa from above

73. compression with laparotomy pads

74. vena caval injuries Large or difficult vena caval injuries may be controlled with a temporary intravascular shunt to maintain venous return while providing vascular isolation of the injured segment. This is a difficult and time-consuming procedure that is best done in the operating room, if the patient survives long enough.

75. Atrial catheter Occasionally, fluid resuscitation can be accomplished by infusing fluid directly into the right atrium. The usual technique for placing atrial catheters using a purse string suture in the right atrium has several disadvantages.

76. Aortic Cross-Clamping When the systolic pressure cannot be raised above 70 mm Hg, temporary occlusion of the descending thoracic aorta can maintain myocardial and cerebral perfusion

78. Aorta Selective clamping is necessary when the aorta has been injured with blunt trauma Aortic occlusion has a limited role in controlling hemorrhage below the diaphragm.

79. prophylactic cross-clamping When there is a tense abdomen with massive hemoperitoneum, aortic cross-clamping is clearly beneficial when applied just before laparotomy. This has been referred to as prophylactic cross- clamping to prevent a sudden drop in blood pressure when the abdomen is decompressed. As a preoperative procedure, cross-clamping should be applied when the systolic pressure is less than 80 mm Hg in the setting of a tense abdomen.

80. Expose the descending aorta To expose the descending aorta, the left lung is retracted in superomedial direction by an assistant. To achieve adequate exposure, it is sometimes necessary to divide the inferior pulmonary ligament.

81. Pleura open Because both the aorta and esophagus are covered on their anterolateral surface by mediastinal pleura, the pleura must be opened and the aorta bluntly dissected away from the esophagus prior to clamping.

82. CLAMPING THE AORTA When the aorta is completely isolated, the index finger of the left hand is flexed around the vessel and a vascular clamp is applied with the right hand. The brachial blood pressure should be checked immediately after the occlusion. If the systolic pressure is more than 120 mm Hg, the clamp should be slowly released and adjusted to maintain a systolic pressure of 120 mm Hg.

83. CLAMPING THE AORTA To locate the aorta, use a DeBakey aortic clamp or a curved Kelly clamp for blunt dissection and spread open the pleura above and below the aorta.

84. Conn aortic compressor The use of a Conn aortic compressor is the method of choice for aortic occ1usion because it is fast, does not interfere with the operative field, and is associated with minimal risk of injury. Conn

85. iatrogenic injury of the aorta and the esophagus may occur. Failure to monitor blood pressure every 60 seconds during aortic occlusion may result in cerebral hemorrhage or left ventricular failure if pressure elevation is excessive. Whenever possible, the aorta was unclamped for 30 to 60 seconds every 10 minutes to increase renal perfusion. Final release of the aorta is always performed gradually.

86. COMPLICATIONS 1)injury to intra-thoracic structures 2)left phrenic nerve and coronary arteries 3)Infection of the wound 4)needle stick or scalpel or scissor injury. 5)HIV 6)hepatitis Band C 7)penetrating trauma 8)appear to be of greater risk of any type of occult infection

87. END