Burns pt 2

Question 1

What are the hallmarks of initial burn therapy?

Answer 1

Within seconds after an acute burn injury, massive fluid shifts begin to occur. Therefore, airway management and volume resuscitation are the hallmarks of initial therapy.

Question 2

Why is aggressive fluid administration important?

Answer 2

To prevent renal failure.
-Loss of circulating plasma volume, hemoconcentration, massive edema formation, decreased urine output, and depressed cardiovascular (CV) function

Question 3

Fluid losses are the greatest at what point? When do they stabilize?

Answer 3

Fluid losses greatest in the first 12 hours, stabilize after 24 hours.

Question 4

How do fluid losses occur?

Answer 4

-Capillary leak results from loss of endothelial integrity and plasma proteins
-Release of inflammatory mediators from burned tissues

Question 5

What is optimal UOP in adults?

Answer 5

0.5 mL/kg/hr

Question 6

When is invasive monitoring indicated?

Answer 6

Invasive hemodynamic monitoring indicated (ABP/CVP/PACs)!!! Espec in patients who do not respond to fluid, have preexisting cardiopulmonary disease, or are at risk of intra abdominal HTN and Abdominal Compartment Syndrome (IAH and ACS significant M&M).
-Catheters removed ASAP due risk of infection

Question 7

What is the Acute Phase of CV response?

Answer 7

Hypovolemia, Hypotension, and Circulatory compromise:
-Loss of intravascular fluid volume
-Loss of vascular/endothelial integrity
-Loss of plasma proteins
-Release of inflammatory mediators

Decreased CO: Hallmark of burn related shock
-Initially preserved via catecholamine response with tachycardia and vasoconstriction

Coronary blood flow can be reduced
SVR increased

Question 8

What is the Hypermetabolic/Dynamic Phase of the CV response?

Answer 8

Increased metabolic rates, multiorgan dysfunction, muscle protein degradation, blunted growth, insulin resistance, and increased risk for infection.

Question 9

What are the primary mediators of the hypermetabolic response after severe burns?

Answer 9

Catecholamines and corticosteroids

Question 10

What are the S/Sx of systemic inflammatory response that occurs with severe burns?

Answer 10

Increased CO
Tachycardia
Decreased SVR
Increased O2 consumption and CO2 production
Inc myocardial oxygen consumption

Question 11

What is the treatment of the hypermetabolic/dynamic phase of severe burns?

Answer 11

-Beta blockers, anti hyperglycemic agents, prevention of sepsis, thermal neutrality, nutritional intervention
-Require aggressive fluid resuscitation in the first 24-36 hours
-Restore intravascular volume and cardiac function

Question 12

What are the immune system effects related to burns?

Answer 12

Within hours, altered immunologic response:
-Depressed leukocyte activity, humoral and cellular responses
-Burn eschar is a prime medium for bacterial growth
-Colonization of Gram (-) bacteria increases mortality
-Sepsis and pneumonia especially with prolonged endotracheal intubation
-Strict aseptic technique is required!!!
-Infection is the leading cause of death in up to 100% children and 75% of adults

Question 13

How common is AKI after burn injuries?

Answer 13

-Acute Kidney Injury (AKI) ~ 40% after major burn injuries
-Myoglobinuria most common after electrical injury
-Hemoglobinuria common after cutaneous burn > 40% TBSA

Question 14

What is the mechanism of AKI developing in burn patients?

Answer 14

Decreased renal blood flow alters GFR, stimulates renin-angiotensin-aldosterone system and the release of ADH to conserve Na+ and water
-Intravascular depletion / hypovolemia
-Decreased CO
-Increased plasma catecholamines

Hourly urine output remains the gold standard!!!
-Minimum 0.5mL/kg/hr

Question 15

What are the GI & Hepatic effects from burns?

Answer 15

-Aggressive nutrition support
-Whole-body catabolism, muscle wasting, cachexia
-Hyperalimentation and lipid infusions
-Tight glucose control secondary to insulin resistance (Monitor perioperatively)
-Overall decrease in GI function with increased risk of ileus
-Increased risk acute GI ulcerations (Acid suppressive therapy: H2 blockers, PPIs, antacids)
-Hepatic effects are variable

Question 16

What are the NPO guidelines for a burn patient?

Answer 16

NPO guidelines considered to prevent reverting to catabolic state:
-Maintain preoperative nutrition without increasing risk of aspiration
-For example, intubated patients do not need enteral feedings discontinued before surgery, whereas non intubated patients may remain on nutritional support up to 4 hours before a scheduled surgical procedure.
-Parenteral hyperalimentation and lipid infusions should be continued intraoperatively.

Question 17

What should be assessed on the preop eval?

Answer 17

Medical History including underlying trauma:
-Past medical Hx
-Mechanism of burn (thermal, electrical, chemical, inhalation)
-Percentage TBSA and location of burn sites

Physical Exam:
-Complete review of systems
-Inspection head/neck/oral cavity – airway management
-Lung auscultation and Chest wall compliance

Labs
Surgical Plan:
-Past surgical and anesthetic Hx
-Selection of anesthetic agents, monitoring, positioning, vascular access, and blood products

Patients are at a greatly increased risk for Altered Mental Status and Compromised Airway

Question 18

What are potential problems you could find in a burn patient?

Answer 18

Altered Mental Status
Compromised Airway
Pulmonary Insufficiency
Dysrhythmia
Renal Insufficiency
Associated Injury
Edema
Impaired Temp Regulation
Immunosuppression
Hypovolemia / Blood loss / Anemia
Decreased Cardiac Fx
Impaired Tissue Perfusion
Vascular Access
Decreased Oncotic Pressure
Altered Drug Response
Infection / Sepsis

Question 19

Describe the OR setup for a burn patient

Answer 19

-Warm the OR
-Blood products immediately available when surgical debridement is initiated.
-Ensure adequate IV access, consider invasive monitoring, and perioperative airway management plan
-Consider postoperative mechanical ventilation
-Have an adequate supply of analgesics and muscle relaxants
-Have a plan but must be willing to modify, adapt, and overcome
-Consider High dose Sufentanil + Isoflurane volatile

Question 20

Describe monitoring of the burn patient

Answer 20

-Standard monitors; may need arterial line if large burns due to significant hemodynamic changes, increased blood loss, intraoperative blood sampling.
-Accurate temperature and urine output monitoring are essential: Esophagus / bladder, foley catheter

Question 21

How do you prevent Hypothermia in the burn patient?

Answer 21

-The temperature in the OR should be between 28°C and 33°C.
-Intravenous solutions and skin preparations should be warmed.
-The use of in-line circuit heat moisture exchangers or lower gas flows will reduce evaporative respiratory tract heat loss.
-Forced-air warming blankets are effective, but their use can be limited depending on the area of excision or surgical exposure.
-Over-body heating lamps have been used but need to be at a safe distance from the patient to prevent further burning.
-Plastic bags also can be helpful to insulate exposed body parts not requiring surgical access.
-Keeping a patient warm is more beneficial than rewarming. Prepare yourself to be hot and uncomfortable!!!

Radiation 60%, Evaporation 25%, Convection 12%, Conduction 3%

Question 22

How are the hemodynamics effected during induction of a burn patient?

Answer 22

Immediate surgery: expect labile hemodynamics within the first 24 hours and exaggerated effects of anesthetics
-Loss of intravascular volume and depressed myocardium
-Careful and slow titration of anesthetic agents
-Consider induction on bed/gurney with subsequent movement to OR table for comfort

Question 23

What meds should be used in the burn patient?

Answer 23

-Appropriate premedication (if stable) with benzos and opioids
-Propofol if stable
-Ketamine if unstable

Question 24

How should you intubate a burn patient?

Answer 24

-No succ if >24 hours
-Use NDMRs
-Video / fiberoptic-assisted techniques
-Awake intubation is safest way
-No unplanned extubations: edema makes re-intubation impossible (Vigilance!)
-Securing tube is challenging

Question 25

What agents should be used during the Maintenance Phase?

Answer 25

Maintenance with an opioid and/or inhalation agents dependent on hemodynamic stability:
-Volatile agents safe and effective, but do not provide analgesia in the postoperative period (Primarily use Isoflurane)
-Opioids are important adjuncts, IV or PCA preferred routes
-Morphine, fentanyl, sufentanil acceptable choices
-Consider Remifentanil for short procedures/dressing changes
-Intubated burn patients often require specialized ventilators, may require TIVA

Question 26

Describe pain management of the burn patient.

Answer 26

Pain management protocols are essential
-Painful procedures: dressing changes, debridements, nursing care, physiotherapy, and surgical procedures
-Multimodal analgesia techniques
-NSAIDS can be effective, weigh hepatorenal function, anticoagulant effects
-Morphine, fentanyl, and sufentanil all provide intra- and postoperative analgesia and are acceptable choices. Remifentanil, a short-acting opioid, may be used for dressing changes.

Question 27

Describe Emergence of the burn patient.

Answer 27

-Emergence and postoperative needs planned in advance
-Critically ill and intubated patients should remain intubated postoperatively
-Safeguard the airway: Edema may make re-intubation difficult/impossible!!!
-Transport directly to the burn unit
-If extubation anticipated, plan for re-intubation
-Postoperative need for sedation and analgesia

Question 28

Can you use Regional Anesthesia in the burn patient?

Answer 28

Yes, used often for procedures in small areas during Reconstructive Phase.
-Provides prolonged postoperative analgesia
-Passing a needle through burned tissue should be avoided due to potential for infection
-Avoid if coagulopathy and cardiorespiratory instability are present or due to Topographical extent of the surgical field

Question 29

Describe the Reconstructive Phase of Burn Management.

Answer 29

-Months - years after discharge, victims return for reconstructive surgery
-Remove and reduce scar tissue
-Prevent contractures and deformity
-Cosmetic and functional outcomes
-Burn patients experience anxiety, stress and depression from prolonged hospitalization
-Most important anesthetic concern is airway management
-Contractures of the face and neck
-Psychological issues are present