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Case Presentation. By Eeman Abou Bakr Assistant lecturer of Anaesthesia and Intensive Care. You have been called to anesthesia and emergency department to provide anesthesia for reduction of a colle’s fracture.
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Case Presentation By Eeman Abou Bakr Assistant lecturer of Anaesthesia and Intensive Care
You have been called to anesthesia and emergency department to provide anesthesia for reduction of a colle’s fracture. • The patients is a 68 years old, heavy smoker and drinker who has been involved in a fire she has burns to her face, chest and arms.
Questions • What assessment of the patients would you make? • Discuss airway assessment, • The significance of perform SaO2 and other investigations you would perform (COHb). • What are the indications for intubations. • What fluid requirements will patients have ? • What fluid would you give, when you give, and why ? • Discuss analgesia, are burns painful ? • Would you give an anesthetic for the fracture ? • Where should the patient be looked after ?
Step 1: Initial Assessment Assessment of the burn patient follows the standard EMS assessment pattern: • Airway: does the patient have a patent airway? • Breathing: is the patient breathing adequately? • Circulation: Is the patient’s circulatory and cardiac status stable? • Neurological status: AVPU Note: burns do NOT alter mentation—if the patient is un-alert or disoriented, something else is going on! • Expose the patient, and treat for hypothermia
Secondary Survey • History: obtain burn specific history • How did the burn occur? • Did the patient’s clothing ignite? • Were accelerants involved? • Was patient found in smoke-filled room? • Did the patient leap from a window, fall, or roll a vehicle? • Are the purported circumstances of the injury consistent with the burn characteristics? Is abuse a possibility?
Secondary Survey (Cont’d.) • Head-to-toe: look carefully for injuries other than the actual burn • Start detailed physical examination • Establish an adequate IV access • Burn injuries are not considered immediate life threats, but they do often accompany traumatic injuries that are life threats!
Step 2: Determining Burn Severity • Burn severity is determined primarily by assessing the extent of the burn as percentage of total body surface area, and its depth • ‘Partial/full thickness’ and ‘1st/2nd/3rd degree’ are acceptable terminology • First and second degree burns are partial thickness burns • Third degree burns are full thickness burns
Determining Burn Severity (Cont’d) • First degree burns (epidermal burns) are red, appear DRY, blanch when pressed upon, and blister mildly. • Second degree (dermal) burns tend to be red or yellowish, appear WET, usually blister, and may or may not blanch • Third degree (subcutaneous) burns appear very DRY, may be yellow, gray or black, do not blanch, and are ‘leathery’ to touch.
Patient is: • 68 yrs old. • Fire – burns to face, chest and arms. • Colle’s fracture. • Heavy smoker. • Drinker. • First of all trauma patient !!
This patient at RISK of developing inhalational injury due to • Unable to escape fire due to • Extremes of age • Immobility due to other trauma • Reduction of level of consciousness: alcohol, drugs, effects of smoke. • Lack of functional smoke detector • Chronic pulmonary disorders: asthma, COPD morbidity of smoke inhalation increased.
Airway assessment (Cont’d) • History - Was the fire in an enclosed space. - Duration of exposure. -What type of material burned, e.g., paints, chemicals. - Level of consciousness on scene.
Airway assessment (Cont’d) • Burns and smoke inhalation victims should be treated as a “trauma” patient, with trauma protocol being followed as routine. This includes cervical immobilization until injury is excluded.
Airway assessment (Cont’d) • Examination - Stridor: indicates severe laryngeal edema and the possibility of imminent airway obstruction - Voice hoarseness—an excellent warning sign - Tachypnea - Use of accessory muscles - Persistent cough - Soot in oropharynx - Singed nasal hair
Carbonaceous particles staining a patient’s face after a burn in an enclosed space. This suggests there is inhalational injury
Airway assessment (Cont’d) • Laryngoscopy detect edema to the pharynx or larynx or vocal cords. • Bronchoscopy • Airway edema • Mucosal slouging • Charring or soot
Discuss the significance to perform SaO2 and other investigations you would perform as(COHb).
Oxygen saturation(SaO2) SaO2 is inaccurate in the presence of significant carboxyhemoglobin (COHb) or methemoglobinemia.
Carbon Monoxide Poisoning • Asphyxiation and/or carbon monoxide poisoning causes most fire scene fatalities • Inhaled carbon monoxide bonds to hemoglobin in the blood, taking the place of oxygen with approximately 200 times greater affinity. • The pulse oximiter, which measures bonded hemoglobin, will deliver a normal reading, even when the patient is hypoxic, or dead
Carbon Monoxide Poisoning • Cherry-red lips, skin and nail beds occur in only 50% of patients with severe carbon monoxide poisoning and are not a clinically reliable indicator • If sufficient carbon monoxide is inhaled, tissue perfusion WILL cease, and the patient WILL die • CO2 removal is not affected, so ET capnography does remain an accurate indicator of ET placement • The only accurate assessment is blood level carboxyhemoglobin, which must be assessed at the hospital
Signs of Carboxyhaemoglobinaemia COHb = Carboxyhaemoglobin
Investigations for major burns General • Full blood count, packed cell volume, urea and electrolyte concentration, clotting screen, liver enzymes • Blood group, and save or crossmatch serum • 12 lead electrocardiography • Cardiac enzymes
Investigations for major burns For inhalational injury: • Arterial Blood Gases—mandatory • Chest x-ray—Frequently normal initially but essential nonetheless as baseline assessment and to exclude trauma.
What are the indications of intubation? • Early intubation required to treat “4” causes of respiratory dysfunction: • 1. CO poisoning • 2. Upper airway edema • 3. Subglottic thermal and chemical burns • 4. Chest wall restriction
What fluid requirement will patient have ? What fluid would you give when you give and why ?
Fluid Resuscitation • Related to: • extent of burn (rule of nines) • body size (pre-injury weight estimate) • Delivered through large bore peripheral IV • Attempt to avoid overlying burned skin • Can use venous cut down or central line
Fluid Resuscitation • Goal: Maintain perfusion to vital organs • Fluid requirement calculations for infusion rates are based on the time from injury, not from the time fluid resuscitation is initiated.
Resuscitation Fluid Needs:First 24 Hours • Parkland Formula: • Adults: 2-4 ml RL x Kg body weight x % burn • First half of volume over first 8 hours, second half over following 16 hours • Hypovolemia, decreased CO • Increased capillary permeability • Crystalloid fluid is keystone, colloid not useful
Fluid resuscitation Lactated Ringers - preferred solution • Contains Na+ - restoration of Na+ loss is essential • Free of glucose – high levels of circulating stress hormones may cause glucose intolerance
Resuscitation Fluid Needs:Second 24 Hours • Capillary permeability gradually returns to normal • 30–50% burn: 0.3 mL/kg body weight per % burn • 50–70% burn: 0.4 mL/kg body weight per % burn • >70% burn: 0.5 mL/kg body weight per % burn Usually check for BP, CVP and urinary output.
Fluid resuscitation • Over resuscitation • Results in: • Pulmonary edema • 3rd spacing of tissues of chest—escharotomies • Prolonged ventilation • Source of morbidity—monitor U/O closely
Analgesia • Pain management is indicated for most burns. • First degree and superficial second degree burns are generally painful. • Full thickness burns are not painful due to destruction of the dermis.
Analgesia Morphine is the drug of choice for pain • Should be titrated intravenously only. • Subcutaneous and intramuscular routes become trapped in tissues by edema and can induce respiratory arrest as the edema resolves which may kill the patient. • Morphine is of choice for (background pain).
For extremely painful procedures in both emergency and acute phase, Fentanyl has a major advantage. • It is shorter acting (procedural pain). • It avoids over sedation following a procedure. • Other drugs as Benzodiazepines may be indicated to clam patients in anxiety induced hyperventilations.
Would you give an anesthetic for the fracture ? • To answer this question we must know what is the pathophysiology of burn injury
Fluid and Electrotype Shifts—EmergentPhase • Generalized dehydration • Reduced blood volume and hemoconcentration • Decreased urine output • Trauma causes release of potassium into extracellular fluid: hyperkalemia • Sodium traps in edema fluid and shifts into cells as potassium is released: hyponatremia • Metabolic acidosis
Fluid and Electrolyte Shifts—Acute Phase • Fluid reenters the vascular space from the interstitial space • Hemodilution • Increased urinary output • Sodium is lost with diuresis and due to dilution as fluid enter vascular space: hyponatremia • Potassium shifts from extracellular fluid into cells: potential hypokalemia • Metabolic acidosis
Three variables estimate a high probability of death • Age > 60 • Burn more than 40% TBSA • Presence of inhalational injury • Other variables include: • Presence of coexisting disease • Delay in resuscitation
Anesthetic management for this patient • Give anesthesia for patients as soon as hemodynamics are stabilized. • Regional anesthesia can be used effectively in small burns or patients undergoing reconstructive procedures. • For upper extremity procedures brachial plexus block may be considered as primary anesthetic or as an adjunct for postoperative pain control. • In this patient as there is injury to both the arms and chest regional anesthesia would be a difficult choice.
Remember also: • Casts over burn must be avoided. • Avoid prolonged immobilization of joints in burn area. • Therefore external and internal fixation techniques are of choice.
Operative management • Ketamine has many advantages for burn patients as an induction and maintenance agent. • Induction dose 0.5-2 mg/Kg. • Ketamine preserves hemodynamics compared to other IV anesthetics. • Airway reflexes remain more intact with small risk of aspiration • Maintenance can be done by volatile agents opioid nitrous oxide.
Muscle relaxants • Succinylcholine is contraindicated un the first 24 hours (cardiac arrest) • Burn patients require higher than normal doses of non depolarizing muscle relaxants duet o altered protein binding and increase in extrajunctional acetyl choline receptors. Note : • Consider alcoholic liver cirrhosis • Consider COPD patient