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Advanced Principles- Fall 2018 > Burns > Flashcards

Flashcards in Burns Deck (27)
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1
Q

What are the incidence of burns?

How many require ER visits?

survival rate?

A
  • 1.25 million burns annually
  • 486,000/year in US require ER visits
  • 40,000 hospitalized
  • 30,000 admitted to a specialized burn center
  • Incidence of burns has decreased secondary to education on prevention and safety regulations
  • survival rate 96.8%
2
Q

What are the different types of urns?

What factors may indicate an inhalational burn?

A
  • Electrical
  • Chemical
  • Inhalational
    • Burned within a closed airspace
    • somebody who lost sonsciousness at the scene
    • cinged nose hairs
  • Thermal (most common)
3
Q

What are the mortality rates for burns?

Who has increased risk of mortality from burns?

A
  • LD50 is burn size >90% TBSA
  • approx. 3,240 die from fire/smoke inhalation injury
    • 2,855 from residential fires
    • 300 from motor vehicle or aircraft
  • ~75% of deaths occur at the scene or during transport
  • ~35% burn victims <17 years old
  • Increased mortality:
    • older age (>60 years)
    • >40% TBSA
    • inhalational injury
4
Q

What are the most common causes of death to a burn patient?

A
  • Infection
  • starvation
  • **Increased survival thanks to early debridement of burns and early and continued nutritional support
5
Q

What are the functions of the integumentary system?

What are the layers of the integumentary system?

A
  • Integumentary system is largest organ
    • protection
    • containment
    • heat regulation
    • sensation
    • vitamin D
  • Layers:
    • Epidermis- top layer
      • avascular
    • Dermis- second layer
      • vascular with afferent nerve endings
    • Fascia
6
Q

How are burns categorized?

A
  • *Categorized based on depth and body surface area
  • 1st degree- epidermis only
    • heals spontaneously
  • 2nd degree-
    • Superficial partial thickness- basement membrane of dermis is intact
      • does not usually require grafting
    • deep dermal- basement membrane of dermis is not intact
      • does require grafting
  • 3rd degree- “full thickness”
    • burn extends into subcutaneous tissue
    • will need grafting
  • 4th degree- muscle, fascia, bone
    • can result in limb loss
7
Q

Know the chart for 1st, 2nd, and 3rd degree burns:

depth

how wound looks

causes

level of pain

healing time

scarring

A
8
Q

What is the rule of 9’s?

A
  • The method used to calculate body surface involved in a burn.
    • Head and neck = 9%
    • Each upper extremity = 9%
    • each lower extremity = 18%
    • anterior trunk = 18%
    • posterior trunk = 18%
    • perineum = 1%
9
Q

Why is the rule of nines inaccurate in calculating TBSA in children?

A
  • because children have proportionally bigger head and trunk
  • a small error in estimation of TBSA can cause a large change in resuscitation plan
10
Q

What is the pathophysiology that occurs after a burn?

A
  • SIRS
  • Every system is affected
  • Necrotic area and ischemic area
    • ischemic area can potentially be saved with adequate resuscitation
  • First minutes to hours:
    • burned tissue releases inflammatory and vasoactive mediators
      • histamine, prostaglandins, kinins, leukotrienes, thromboxane, and NO
  • Later:
    • reperfusion injury- will produce reactive O2 species that will cause further damage and and propagate the immune response
11
Q

What is significant about the zone of stasis?

A
  • The zone of stasis is the area that can be salvaged with the appropriate resuscitation
    • without adequate resuscitation the zone of stasis will be lost
12
Q

What happens with electrical burns?

A
  • Devastating injuries to bones, blood vessels, muscle and nerves
  • Extent of tissue damage is based on voltage and duration
    • Most damage concentrated at entry and exit points
  • 10-46% have cardiac arrhythmias and maybe damage to myocardium
  • Massive muscle damage will lead to renal failure d/t myoglobinemia
13
Q

Chemical burns:

usual cause?

what does it do?

treatment?

A
  • Usually caused by occupational injury
  • The chemical causes a reaction with tissue proteins and cellular components that leads to tissue destruction
  • Treatment: Must neutralize!
    • copious irrigation
14
Q

Thermal burns:

Who is usually affected?

A
  • Scald injuries account for up to 70% of burns in children < 4 years old
  • Children >5 years usually have flame burns
  • 15-20% of burns are NAT caused by abuse or neglect
15
Q

Inhalational injury:

symptoms

usual causes

A
  • Symptoms:
    • hoarseness
    • sore throat
    • dysphagia
    • hemoptysis
    • tachypnea
    • accessory muscle usage
    • wheezing
    • carbonaceous sputum
    • increased CO levels
  • Causes:
    • thermal burns, likely in a closed space.
    • suspect if pt was unconscious at the scene
16
Q

What are the three types of inhalational injuries?

A
  • Upper airway injuries
    • inhalation of superheated air/steam
    • may spare lower airway d/t reflexive vocal cord closure if dry heat, less likely with steam
  • Lower airway/parenchymal
    • soot particle/chemical inhalation
    • will cause massive bronchospasm
  • Metabolic asphyxiation- CO, etc
17
Q

What is the flow of the pathophysiology of an inhalation injury?

(small flow chart)

A
  • the Conversion of xanthine oxidase causes the breakdown of purines to uric acid which creates reactive oxygen species
  • The Reactive oxygen species combine with nitrous oxide(??), increase the microvascular pressure and the permeability to protein
  • Neutrophils will be stiff and non-deformable b/c they are injured. This causes further release of oxygen radicals and further propagates the injury
18
Q

Describe the large complicated flow chart of the pathophysiology of an inhalational injury.

A
19
Q

What are the indications for early tracheal intubation after an inhalation injury?

A
20
Q

When should you suspect CO poisoning?

How does CO affinity for Hgb compare to O2?

What does CO do to pH?

A
  • Suspect CO poisoning with inhalational injuries
    • dectect it with arterial COHgb levels
  • Severity of symptoms will correlate with COHgb levels
    • >30% COHgb requires high FiO2 to reduce half life
    • always provide high FiO2 until it is proven the person does NOT have an inhalational injury/CO poisoning
  • CO has 200 times greater affinity for hemoglobin than oxygen
  • CO causes metabolic acidosis
21
Q

How does CO affect the oxyhemoglobin dissociation curve?

How does CO interact with myoglobin?

How does CO affect SpO2?

A
  • CO causes LEFT shift on oxy-hgb dissociation curve, reducing the oxygen release from the hgb.
  • CO has a greter affinity for myoglbin than for hgb
    • CO binding to cardiac myoglobin leads to myocardial depression, hypotension, and arrhythmias
  • CO causes falsely elevated pulse oximetry readings
22
Q

When would you see cherry red colored blood?

A

If carboxyhemoglobin level is >40%

23
Q

What are the symptoms of CO poisoning?

(chart)

0-10%

10-20%

20-30%…

A
24
Q

What does cyanide poisoning do?

What are the symptoms of cyanide poisoning?

What is the antidote and how does it work?

A
  • Cyanide poisoning leads to tissue hypoxia by blocking the intracellular use of oxygen
    • it binds to the terminal cytochrome on the exectron transport chain
    • result is hypoxia, lactic acidosis, and elevated mixed venous oxygen saturation
  • Symptoms:
    • LOC
    • mydriasis (dilated pupils)
    • sz
    • hypotension
    • tachypnea then apnea
    • increased lactate levels
  • Antidote: Hydroxocobalamin (vit B 12)
    • actively binds cyanide by forming cyanocobalamin
    • directly excreted in kidney
25
Q

What materials give off CO?

What materials give off cyanide?

(table)

A
26
Q

What pharmacokinetic changes will you see in a pt during burn shock?

What about during the hypermatabolic phase?

A
  • Burn shock: generally decreased requirements
    • reductions in renal and hepatic blood flow
    • prolonged rate of drug distribution
    • prolonged onset of clinical effects
  • Hypermetabolic phase: generally increased requirements
    • decreased albumin
    • increased a1-acid glycoprotein
    • denervation phenomenon with spreading of acetylcholine receptors (no succ!)
    • increased nicotinic acetylcholine receptors and decreased function
27
Q

What are some considerations for these drugs in a patient with major burns? (table)

fluids

succs

NDMR

IV anesthetics

inhalation agents

beta blockers

insulin

A