81. Burns Flashcards

1
Q

Thermal burns occur during heat or cold transfer. What are ways heat is transferred?

A
  1. Conduction–direct contact2. Convection–airborne3. Radiation–electromagnetic energy interaction(also evaporation chapter 23–anesthesia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Surface area classification of wounds

A

Rule of 9sHead/neck 9, ea forelimb 9, ea hindlimb 9Dorsal trunk 18Ventral trunk 18Burn card= 45cm2(# cards x .45)/ m2 (standardized body weight to surface area)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Local response to thermal burn injuryZones

A

Zone of coagulation– inner, irreversible, nonviable, necrosis, destructionZone of stasis– poor perfusion, vulnerableZone of hyperemia–outer, viable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why are burns more likely to heal slowly

A

They have < 5% of normal levels of fibroblast growth factor 2And lack endothelial chemotactic activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Generalized cardio effects from smoke inhalation

A

Vascular permeability of fluid and albumin–overwhelms lymphaticsOther fluid loss through evaporation (direct loss from skin)RBC deformability both extravasation and evaporation lead to hypovolemia= hyperviscosity, poor perfusion, hypoxemia20% TSA burn cause 28% loss of plasma volume w/in 6 hr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Myocardial effects from smoke inhalation

A

Carbon monoxide toxicity causes myocardial damage and decreased cardiac outputOxidative injury to sarcolemma causes incr myocyte intracytoplasmic CaThermal injury also injures Na/Ca channels causes incr myocyte intracytoplasmic CaLeads to decrease left ventricular contractility and CO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Burn anemia

A

10 % RBCs become trapped and destroyed in large burn RBC fragility and membrane damage Intravascular hemolysisReduced erythropoiesis from decreased iron stores despite EPO release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pharmacological therapy for smoke inhalation

A

Aerosolized sympathomimetic bronchodilators–epinephrine Nacetylcysteine–mucolytic that forms free sulfhydryl radicals that break down disulfide bonds in muco proteins but can cause bronchospasms ; Nacetylcysteine l lysinate is an improved formLow molecular wt dextran— makes mucus bonds weaker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

3 types of pain w burn injury

A
  1. Procedural pain–most intense, during tx, sharp, burning, stinging, most likely under treated2. Background pain– prolonged relatively constant pain, burning, throbbing, usually during immobility3. Breakthrough pain– transient worsening of pain usually associated w movement, stinging, shooting (treated with CRI or shortening the dosing interval)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How to treat a doxorubicin extravasation

A

Not neutralized during run therefor continually causes local rxn1. Local excision2. Local injection of hyaluronidase ( to promote vascular uptake of drug)3. Infiltration of dexrazoxane (dimethyl sulfoxide) as free radical scavenger by binding iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

initial response to tissue trauma from burn

A

vasodilation (under cytokine control)NO, PGE2, Histamine, Substance P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

toxic substances in smoke inhalation

A

250 toxic substance–Carbon monoxide–binds w Hb to make carboxyhemoglobin wh reduces o2 carrying capacity and causes left shift of oxyhemoglobin dissociation curve reducing o2 delivery to tissues; also binds w Mb reducing o2 available to muscle –Hydrogen cyanide– disrupts cellular respiration –hydrochloride–irritants leading to laryngeal and broncho spasms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

initial first aid for burns

A

cool to cold running water NOT ICEoptimum temp 15 degrees Ccooling with ice causes extreme drops in sub dermal temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

goals of bronchial hygiene for treatment of smoke inhalation

A
  1. minimize ongoing pulmonary inflammation2. improve gas exchangeinclude oxygen, nebulization and coupage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

benefits of oxygen for tx of smoke inhalation

A

supplemental oxygen speeds the removal of carbon monoxide from bloodaffinity of Hb for carboxyHb is 240x higher than affinity for oxygen, need to saturate blood with oxygen to overcome difference in affinity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

half life of carbon monoxide in room air vs FIO2 at 40%

A

room air carbon monoxide half life is >4 hoursFI02 at 40% half life decreases to < 1 hourhyperbaric oxygen decreases it to <30 min

17
Q

ultimate goal of nutritional support for burn patients

A

to ameliorate two twin effects of hyperglycemia (burn diabetes) and hypercatabolism

18
Q

methods to improve nutritional and metabolic conditions in a burn patient

A
  1. environment should be warm and relatively humid2. wounds should be covered3. analgesia and sedation4. nutrition
19
Q

pharmacologic intervention to stop burn diabetes and hypercatabolism

A
  1. beta adrenergic blockers–propanolol2. insulin
20
Q

joules law

A

total energy delivered to tissue (J) = I^2 RTI amperage squaredR tissue resistanceT duration of exposurepredicts that the tissue with HIGHER resistance will sustain GREATER DAMAGE

21
Q

why is a common finding in animals with electrical burns

A

MYOGLOBINURIA bc of severe damage to underlying musclesneed aggressive fluid therapy to avert from renal toxicity

22
Q

frostbite

A

exposure to colddistal extremities and flank folds are susceptibletissue freezing causes crystallization intra and extracellularly, also induced vasoconstriction occurs leading to poor perfusion