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Care of the Unconscious; Multiple Trauma / Burns Patient Lasonya A. Fletcher Medical Student, Class of 2015 Anaesthesiology, August 2013 2013 Prepared by Lasonya A. Fletcher 1

Anaesthetic Care of the Unconscious, Multiple Trauma and Burns Patient

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  • 1.Care of the Unconscious; Multiple Trauma / Burns Patient Lasonya A. Fletcher Medical Student, Class of 2015 Anaesthesiology, August 2013 2013 Prepared by Lasonya A. Fletcher 1

2. Introduction Trauma accounts for 10%-15% of all patients hospitalized. Trauma is the leading cause of death in Americans from the first to the thirty-fifth year of age. Fifty percent of trauma deaths occur immediately, with another 30% occurring within a few hours of injury (the "golden hour"). Anaesthesiologists directly affect the survival of trauma victims most victims require immediate surgery Role of anaesthesiologist: Often that of primary resuscitator, with provision of anesthesia a secondary activity. 2013 Prepared by Lasonya A. Fletcher 2 3. Case Car 1: Two Adults, Male teenager, female child Car 2: Two Adults, Male child Van: One Adult Expected injuries? Appropriate Management? 2013 Prepared by Lasonya A. Fletcher 3 4. Initial Evaluation 1 Survey [2-5 mins.] Airway Breathing Circulation Disability Exposure 2 Survey Head-to-toe Examination Relevant Investigations Definitive Repair of Injuries 3 Survey Repeat Head-to-toe Exam Repair remaining/arising injuries Resuscitation and Assessment Control of Haemorrhage and Definitive repair of Injury 2013 Prepared by Lasonya A. Fletcher 4 5. PRIMARY SURVEY 2013 Prepared by Lasonya A. Fletcher 5 6. Primary Survey Airway and Cervical Spine Establishing and maintaining airway = first priority If patient can talk airway usually clear If patient is unconscious likely require airway and ventilator assistance Signs of obstruction: stertor (snoring), stridor, gurgling, paradoxical chest movements If there is apnoea, persistent obstruction, severe head injury, maxillofacial trauma, penetrating neck injuries with an expanding hematoma or major chest injuries Advanced airway management is indicated (endotracheal intubation, cricothyrotomy or tracheostomy) 1A 2013 Prepared by Lasonya A. Fletcher 6 7. Primary Survey Airway and Cervical Spine Cervical spine injury unlikely in alert patients without neck injury or tenderness Five criteria increase the risk of cervical spine instability: 1. Neck pain 2. Severe distracting pain 3. Any neurological signs and symptoms 4. Intoxication 5. Loss of consciousness at the scene A cervical spine fracture must be assumed if any one of these criteria is present, even if there is no known injury above the level of the clavicle. 1A 2013 Prepared by Lasonya A. Fletcher 7 8. Primary Survey Airway and Cervical Spine Unconscious patients with major trauma are at risk for aspiration therefore airway should be secured quickly with an endotracheal tube or tracheostomy. Neck hyperextension and axial traction should be avoided Use MILS (Manual In-line Stabilization) Nasal intubation should be avoided in patients with mid-face or basilar skull fractures. 1A 2013 Prepared by Lasonya A. Fletcher 8 9. Primary Survey Breathing Look Listen Feel 1B 2013 Prepared by Lasonya A. Fletcher 9 10. Primary Survey Breathing Look 1B Cyanosis Use of accessory muscles Flail chest Penetrating or sucking chest injuries. 2013 Prepared by Lasonya A. Fletcher 10 11. Primary Survey Breathing Listen 1B Presence, absence, or diminution of breath sounds. 2013 Prepared by Lasonya A. Fletcher 11 12. Primary Survey Breathing Feel 1B Subcutaneous emphysema Tracheal shift Broken ribs The clinician should have a high index of suspicion for tension pneumothorax and haemothorax particularly in patients with respiratory distress. 2013 Prepared by Lasonya A. Fletcher 12 13. Primary Survey Circulation Adequacy of circulation is based on pulse rate, pulse fullness, blood pressure, and signs of peripheral perfusion. Signs of inadequate circulation include tachycardia, weak or unpalpable peripheral pulses, hypotension, and pale, cool, or cyanotic extremities. First Priority in maintaining adequate circulation: STOP BLEEDING Second priority: Replace intravascular volume Cardiac arrest during transport or shortly after arrival at hospital following penetrating chest injury is an indication for emergency room thoracotomy Pregnant patients at term who are in cardiac arrest or shock often cannot be resuscitated properly until after the delivery of the baby. 1C 2013 Prepared by Lasonya A. Fletcher 13 14. Primary Survey Circulation Haemorrhage Obvious sites identify and control with direct pressure Extremity bleeding pressure dressings and packs Bleeding due to chest trauma (possibly intercostal arteries) may slow down or stop when the lung has re- expanded after the insertion of a chest tube. Bleeding due intra-abdominal injuries may tamponade itself, depending on the severity Pneumatic antishock garments may work to stop bleeding in the abdomen and lower extremities but are contraindicated in cases of bleeding above the garment Tourniquets can cause reperfusion injuries 1C 2013 Prepared by Lasonya A. Fletcher 14 15. Primary Survey Circulation The trauma patient may be in shock most commonly hypovolemic shock Physiological responses: tachycardia, poor capillary perfusion, and a decrease in pulse pressure, hypotension, tachypnea, and delirium. The mainstay of therapy of hemorrhagic shock is intravenous fluid resuscitation and transfusion Multiple short (1.52 in), large-bore (1416 gauge or 78.5F) catheters are placed in easily accessible veins. Central lines may be useful but are time-consuming and introduce possible life-threatening complications 1C 2013 Prepared by Lasonya A. Fletcher 15 16. Primary Survey Circulation FluidTherapy Choice of fluid initially is usually based on availability Fully cross-matched blood ideal time- consuming to obtain Type-specific blood is appropriate but may cause minor antibody reactions Uncrossed O-neg packed RBCs should be reserved for life-threatening losses that cannot be replaced by other fluids 1C 2013 Prepared by Lasonya A. Fletcher 16 17. Primary Survey Circulation FluidTherapy Crystalloid solns readily available and inexpensive Resuscitation requires large quantities of crystalloids Lactated Ringer's soln is less likely to cause hyperchloremic acidosis than is normal saline Dextrose-containing solns may exacerbate ischemic brain damage In the presence of cerebral edema, hypertonic solns (3% or 7.5% saline) are effective for volume resuscitation 1C 2013 Prepared by Lasonya A. Fletcher 17 18. Primary Survey Circulation FluidTherapy Colloids more expensive than crystalloids but more effective in rapidly restoring intravascular volume Albumin is usually selected over dextran or hetastarch due to the fear of inducing a coagulopathy Whichever fluid is chosen must be warmed prior to administration. Hypothermia worsens acid-base disorders, coagulopathy and myocardial dysfunction. It also shifts the oxygen-hemoglobin curve to the left and decreases the metabolism of lactate, citrate and some anesthetic drugs *MonitorVital Signs!! (Blood pressure, pulse pressure and heart rate) 1C 2013 Prepared by Lasonya A. Fletcher 18 19. Primary Survey Circulation FluidTherapy CentralVenous pressure and urinary output indications of restoration of vital organ perfusion Inadequate organ perfusion interferes with aerobic metabolism produces lactic acid and metabolic acidosis Hypotension in patients with hypovolemic shock should be aggressively treated with IV fluids and blood products NOT vasopressors unless there is profound hypotension unresponsive to fluid therapy Shock refractory to aggressive fluid therapy may be due to uncontrolled haemorrhage that exceed the rate of transfusion 1C 2013 Prepared by Lasonya A. Fletcher 19 20. Primary Survey Disability Evaluation for disability consists of a rapid neurological assessment. Because there is usually no time for a Glasgow Coma Scale the AVPU system is used: awake verbal response painful response unresponsive. 1D 2013 Prepared by Lasonya A. Fletcher 20 21. Primary Survey Exposure The patient should be undressed to allow examination for injuries. In-line immobilization should be used if a neck or spinal cord injury is suspected. 1E 2013 Prepared by Lasonya A. Fletcher 21 22. SECONDARY SURVEY 2013 Prepared by Lasonya A. Fletcher 22 23. Secondary Survey Begins once the ABCs have been stabilized Patient evaluated from head to toe and the indicated studies carried out Basic laboratory investigations include: complete blood count Electrolytes Glucose Blood urea nitrogen (BUN) Creatinine Arterial blood gases Chest X-ray Cross-table lateral and swimmers view Skull, pelvic and long bones Focused assessment with sonography (FAST) CT Chest Peritoneal lavage 2 2013 Prepared by Lasonya A. Fletcher 23 24. Secondary Survey Head-toe-Assessment: Main Points Head: injuries to scalp, eyes and ears Neuro: Glasgow Coma Scale, evaluation of sensory and motor function Chest: auscultate and inspecte again for fractures and functional integrity Diminished breath sounds may indicate a pneumothorax Distant heart sounds may indicate pericardial tamponade Abdomen: inspection, auscultation, and palpation. Extremities: examine for fractures, dislocations, and peripheral pulses A urinary catheter and nasogastric tube are also normally inserted 2 2013 Prepared by Lasonya A. Fletcher 24 25. Secondary Survey 2 Eye Opening Spontaneous (4) To verbal command (3) To pain (2) None (1) BestVerbal Response Oriented conversation (5) Disoriented conversation (4) Inappropriate words (3) Incomprehensible words (2) Incomprehensible sounds (2) None (1) Best Motor Response Obeys verbal command (6) Localizes painful stimuli (5) Flexion withdrawal from painful stimuli (4) Decorticate response to painful stimuli (3) Decerebrate response to painful stimuli (2) None (1) Glasgow Coma Scale 2013 Prepared by Lasonya A. Fletcher 25 26. TERTIARY SURVEY 2013 Prepared by Lasonya A. Fletcher 26 27. Tertiary Survey Tertiary Survey defined as a patient evaluation that identifies and catalogues all injuries after initial resuscitation and operative interventions. Typically occurs within 24 h of injuries. Delayed evaluation normally results in a more awake patient who is able to fully communicate all complaints, more detailed information on the mechanism of injury, and a detailed examination of the medical record to determine preexisting comorbidities. 3 2013 Prepared by Lasonya A. Fletcher 27 28. Tertiary Survey The tertiary survey occurs prior to discharge to reassess and confirm known injuries and identify occult ones. Includes another "head-to-toe examination" and a review of all laboratory and imaging studies. Missed injuries can include extremity and pelvic fractures, spinal cord and head injuries, and abdominal and peripheral nerve injuries 3 2013 Prepared by Lasonya A. Fletcher 28 29. General Considerations Head and Spinal Trauma Chest Trauma Abdominal Trauma Extremity Trauma 2013 Prepared by Lasonya A. Fletcher 29 30. If a patient arrives in the operating theatre already intubated, correct positioning of the endotracheal tube must be verified Patients with suspected head trauma hyperventilate to decrease intracranial pressure Ventilation may be compromised by pneumothorax, flail chest, obstruction of endotracheal tube or direct pulmonary injury 2013 Prepared by Lasonya A. Fletcher 30 31. If a patient is not intubated then proper airway management principles should be followed. Where possible, hypovolemia should be at least partially corrected prior to induction. Fluid resuscitation and transfusion should continue throughout induction and maintenance of anaesthesia. Commonly used induction agents for trauma patients include ketamine and etomidate 2013 Prepared by Lasonya A. Fletcher 31 32. A 'rapid sequence induction' is used when a patient requires general anaesthesia who has been identified as having risk factors for gastric aspiration. 2013 Prepared by Lasonya A. Fletcher 32 33. Technique for Rapid Sequence Induction 1. Prepare for General Anaesthesia 2. Turn on pharyngeal suction apparatus 3. Have patient breath 100% O2 4. Position head in sniffing position 5. Consider patients size, age and state of health to determine ideal dose of induction agent. Give dose + 1mg/kg succinylcholine in quick succession. 6. As soon as the patient has lost consciousness, apply pressure to cricoid cartilage (Sellicks manoeuver) 7. Reconfirm posture and intubate trachea at onset of paralysis 8. Inflate cuff of endotracheal tube before releasing cricoid pressure 9. Check position of ET tube, make adjustments and secure in place2013 Prepared by Lasonya A. Fletcher 33 34. Any trauma victim with altered consciousness must be considered to have a brain injury The level of consciousness is assessed by serial Glasgow Coma Scale evaluations Injuries requiring immediate surgical intervention: epidural hematoma, acute subdural hematoma, some penetrating brain injuries and depressed skull fractures. Injuries managed conservatively: basilar skull fracture and intracerebral hematoma. 2013 Prepared by Lasonya A. Fletcher 34 35. Basilar skull fractures are often associated Raccoon eyes" Battle's sign CSF rhinorrhea Other signs of brain damage include restlessness, convulsions, and cranial nerve dysfunction The classic Cushing triad (hypertension, bradycardia, and respiratory disturbances) is a late and unreliable sign that usually just precedes brain herniation Patients suspected of sustaining head trauma should not receive any premedication that will alter their mental status or neurological examination 2013 Prepared by Lasonya A. Fletcher 35 36. Brain injuries intracranial pressure from cerebral haemorrhage and edema Controlled by fluid restriction (except in hypovolemic shock) diuretics [0.5g/kg mannitol] Barbiturates Deliberate hypocapnia [PaCo2 of 28-32 mm Hg] *Hypertension or tachycardia during intubation can be attenuated with intravenous lidocaine or fentanyl. 2013 Prepared by Lasonya A. Fletcher 36 37. The degree of physiological derangement following spinal cord injury is proportional to the level of the lesion. Lesions of the cervical spine may involve the phrenic nerves (C3C5) and cause apnea. Loss of intercostal function limits pulmonary reserve and the ability to cough. High thoracic injuries will eliminate sympathetic innervation of the heart (T1T4), leading to bradycardia. Acute high spinal cord injury can cause spinal shock, a condition characterized by loss of sympathetic tone in the capacitance and resistance vessels below the level of the lesion, resulting in hypotension, bradycardia, areflexia, and gastrointestinal atony2013 Prepared by Lasonya A. Fletcher 37 38. Succinylcholine is reportedly safe during the first 48 h following the injury but is associated with life-threatening hyperkalemia afterward. Short-term high-dose corticosteroid therapy with methylprednisolone (30 mg/kg followed by 5.4 mg/kg/h for 23h) improves the neurological outcome of patients with spinal cord trauma. 2013 Prepared by Lasonya A. Fletcher 38 39. Chest Trauma may severely compromise the function of the heart or lungs, leading to cardiogenic shock or hypoxia Simple Pneumothorax Tension Pneumothorax Multiple rib fractures Hemomediastinum Pulmonary Contusion Cardiac Tamponade Anaesthetic Mx: maximize cardiac inotropism, chronotropism and preload Ketamine is a favored induction agent 2013 Prepared by Lasonya A. Fletcher 39 40. Chest Trauma may also result in Myocardial contusion Aortic transection or aortic dissection Avulsion of the left subclavian artery Aortic or mitral valve disruption Traumatic diaphragmatic herniation Esophageal rupture. Acute respiratory distress syndrome (ARDS) is usually a delayed pulmonary complication of trauma that has multiple causes: sepsis, direct thoracic injury, aspiration, head injury, fat embolism, massive transfusion, and oxygen toxicity.2013 Prepared by Lasonya A. Fletcher 40 41. Patients involved in major trauma should be considered to have an abdominal injury until proved otherwise Abdominal trauma is usually divided into penetrating (eg, gunshot or stabbing) and non-penetrating (eg, deceleration, crush, or compression injuries). Penetrating abdominal injuries are usually obvious with entry marks on the abdomen or lower chest. The most commonly injured organ is the liver. Patients tend to fall into three subgroups: (1) pulseless, (2) hemodynamically unstable, and (3) stable. 2013 Prepared by Lasonya A. Fletcher 41 42. Pulseless and hemodynamically unstable patients (those who fail to maintain a systolic blood pressure of 8090 mm Hg with 12 L of fluid resuscitation) should be rushed for immediate laparotomy. Stable patients with clinical signs of peritonitis or evisceration should also undergo laparotomy as soon as possible Hemodynamically stable patients with penetrating injuries who do not have clinical peritonitis require close evaluation to avoid unnecessary laparotomy2013 Prepared by Lasonya A. Fletcher 42 43. Profound hypotension may follow opening of the abdomen as the tamponading effect of extravasated blood (and bowel distention) is lost.. Nitrous oxide is avoided to prevent worsening of bowel distention. A nasogastric tube (if not already present) will help prevent gastric dilation but should be placed orally if a cribriform plate fracture is suspected. Massive abdominal hemorrhage may require packing of bleeding areas and/or clamping of the abdominal aorta until bleeding sites are identified and the resuscitation can catch up with the blood loss.2013 Prepared by Lasonya A. Fletcher 43 44. Extremity injuries can be life-threatening because of associated vascular injuries and secondary infectious complications. Fat emboli are associated with pelvic and long-bone fractures and may cause pulmonary insufficiency, dysrhythmias, skin petechiae, and mental deterioration within 13 days after the traumatic event Compartment syndrome can occur following large hematomas, crush injuries, fractures and amputation injuries If the injury is isolated, a regional technique (eg, brachial or interscalene plexus block) is often recommended to increase peripheral blood flow by interrupting sympathetic innervation. During general anesthesia, the patient should be kept warm, and emergence shivering must be avoided to maximize perfusion. 2013 Prepared by Lasonya A. Fletcher 44 45. CASE A 43-YEAR-OLD MAN WHO SUFFERED A MAJOR THERMAL BURN 7 DAYS PREVIOUSLY IS SCHEDULED FOR EXCISION AND GRAFTING UNDER GENERAL ANESTHESIA 2013 PREPARED BY LASONYA A. FLETCHER 46 46. CLASSIFICATION OF BURNS From Bailey and Loves Short Practice of Surgery th Burn injuries are described according to the percentage of body surface area involved and the depth of the skin destroyed. Survival is influenced by the percentage surface area involved and the age of the patient. The rule of nines divides the body's surface area into areas of 9% or multiples of 9% The surface area of one side of the patient's hand represents 1% of total body surface area. First-degree burns are limited to the epithelium, second- degree burns extend into the dermis, and third-degree burns destroy the entire skin thickness 2013 PREPARED BY LASONYA A. FLETCHER 47 47. PULMONARY PATHOPHYSIOLOGY ASSOCIATED WITH MAJOR BURN INJURIES Direct inhalational injury is usually limited to upper airway edema that can lead to life- threatening airway obstruction. Lower airways can also be subjected to direct thermal insult (eg, steam) or can be injured by exposure to smoke and toxic products of combustion. Deactivation of surfactant can lead to atelectasis and pulmonary shunting. Permeability can be increased throughout the entire microvascular system contribute to the development of pulmonary edema and acute respiratory distress syndrome. Circumferential burns of the thorax may decrease chest wall compliance and further increase peak inspiratory pressures . Carbon monoxide inhalation shifts the oxygenhemoglobin curve to the left (interfering with the unloading of oxygen at tissues) and decreases oxyhemoglobin saturation. 2013 PREPARED BY LASONYA A. FLETCHER 48 48. CARDIOVASCULAR EFFECTS ASSOCIATED WITH BURN INJURIES Increases in permeability at the site of injury and throughout the microvasculature cause a tremendous shift of fluid from the plasma volume to the interstitial space. Hematocrit may rise as a result of the contraction of intravascular volume. Cardiac output declines as a result of the contraction of plasma volume and a circulating myocardial depressant factor. If volume replacement does not provide an adequate diuresis (1 ml/kg/h), inotropic support with dopamine may be beneficial. 2013 PREPARED BY LASONYA A. FLETCHER 49 49. ELECTROLYTE DERANGEMENTS FOUND IN BURN PATIENTS Hyperkalemia from tissue destruction may complicate management during the acute resuscitation phase. Later, renal wasting and gastric losses may result in hypokalemia Topical antibiotic therapy may also cause electrolyte imbalances Electrical burns are associated with such severe muscle cell damage that myoglobinuria can lead to renal failure. 2013 PREPARED BY LASONYA A. FLETCHER 50 50. MONITORS THAT WOULD BE USEFUL DURING THIS EXCISION AND GRAFTING PROCEDURE At least two large-bore intravenous lines, an arterial line, and often a central venous catheter or pulmonary artery catheter are indicated. A central triple-lumen catheter can be helpful in patients with difficult intravenous access. A noninvasive blood pressure unit should be used as a backup to the arterial line, which may malfunction if the patient is frequently repositioned. Electrocardiograph skin electrodes will not stick to burned areas, and they interfere with chest wall excision. As an alternative, needle electrodes are often sutured in place. Hypothermia can be minimized by using warming blankets and heat lamps, increasing operating room temperature, humidifying inspired gases, and warming intravenous fluids. 2013 PREPARED BY LASONYA A. FLETCHER 51 51. SPECIAL INTUBATION CONSIDERATIONS IN THESE PATIENTS Burn victims with inhalational injury will often be intubated prior to surgery. Indications for early intubation include hypoxia not correctable with a face mask, upper airway edema that may progress to obstruction, or the presence of copious secretions. Impending airway obstruction or severe facial contractures call for an awake fiberoptic intubation. Tracheostomies have been associated with increased morbidity in burn patients because of pulmonary sepsis. 2013 PREPARED BY LASONYA A. FLETCHER 52 52. HOW DOES A BURN INJURY AFFECT THE PHARMACOLOGY OF ANESTHETIC DRUGS? Succinylcholine is contraindicated in burn patients after the first 24 h. Its administration has caused cardiac arrest because of dramatic increases in serum potassium levels. Burn patients require higher than normal doses of non-depolarizing muscle relaxants. This resistance is due to altered protein binding and an increased number of extra-junctional acetylcholine receptors, which bind non-depolarizing drug without causing a neuromuscular effect. Volatile anesthetics will exacerbate myocardial depression but are useful after the acute phase. Because of the potential for serious dysrhythmias, halothane is best avoided if epinephrine- soaked bandages are being used to decrease blood loss 2013 PREPARED BY LASONYA A. FLETCHER 53 53. REFERENCES G. Edward Morgan, Jr., Maged S. Mikhail, Michael J. Murray Clinical Anaesthesia 4th ed. 2007 The Mcgraw-Hill Companies. Chap 41 Sullivan, Pat Anaesthesia for Medical Students 1999 Department of Anaesthesia, Ottawa Civic Hospital Barash, P Handbook of Clinical Anaesthesia 6th ed. 2009 Lippincott Williams and Wilkins pp 460-478 Gwinutt, C Lecture Notes: Clinical Anaesthesia 2nd ed. 2004 Blackwell Publishing Williams, N et al. Bailey and Loves Short Practice of Surgery 25th ed. 2008. Edward Arnold Publishers. Pp 271-394 Bickley, L Bates Guide to Physical Examination and History Taking 10th ed. 2009. Lippincott Williams and Wilkins 2013 Prepared by Lasonya A. Fletcher 54 54. THE END ANY QUESTIONS? 2013 Prepared by Lasonya A. Fletcher 55