Chapter 33 - Burns and Frostbite

Question 1

First degree burns

Answer 1

involve epidermis only

no blistering

no \tissue death

Question 2

second degree burns

Answer 2

penetrate dermal layer

most painful

regenerative dermal compnents are in the hair follicles and sweat glands - no skin grafting required

Question 3

third degree burns

Answer 3

leave no tissue capable of spontaneous regeneration

all dermal layers involved

nerve endings gone - not painful

Question 4

fourth degree burns

Answer 4

require flaps

bone and tendon involvement

Question 5

Protein rich edema fluid after burns promotes what?

Answer 5

scarring, contracture, stiffness

Question 6

HO in burns

Answer 6

most commonly about the elbow between the medial epicondyle and the olecranon
1-3% of burn patients

Question 7

escharotomy incisions should be placed where?

Answer 7

midaxial along the elbow and digits

Question 8

fasciotomy is more commonly required in what type of burns?

Answer 8

electrical

Question 9

burned hands tend to fall quickly into what posture?

Answer 9

intrinsic minus - extended MCP, Flexed PIP, DIP

Question 10

how to prevent intrinsuc minus contracture?

Answer 10

splint in intrinsic plus - mcp flexion pip, dip extension

Question 11

Web space contractures - cause and how to treat

Answer 11

fibrosis of the CMC capsule, adductor pollicis, first dorsal interosseus musculature

z plasty, skin grafting, intermetacarpal pinning

Question 12

how to treat intrinsic minus clawing deformity

Answer 12

release of the contracted MCP capsule, palmar IP capsule, subcu tissue and skin

if extensor mechanism unable to be mobilized, PIP arthrodesis

Question 13

how to treat elbow contractures

Answer 13

simple contractures - z-plasty, more complex - scar excision plus skin grafting or flap coverage

Question 14

electrical burns cause what mechanism of damage?

Answer 14

electrical energy yis converted to heat in deeper tissues - results in vessel thrombosis and coagulation necrosis

Question 15

cardiac complications in electrical burns

Answer 15

with AC currents (most common) - ventricular arrhythmias

Question 16

other physiologic complications of electrical burns

Answer 16

myoglobinuria - keep UOP at 2ml/kg/hr

Question 17

Acid burns pathophys

Answer 17

cause cellular dehydration, cell membrane destruction, liquefaction necrosis

Question 18

alkali burn pathology

Answer 18

less common than acid burns

penetrate deeper than acid burns via cellular dehydration

cause saponification of adipose tissues

Question 19

specific neutralization agents for chemical burns

Answer 19

hydrofluoric acid -> fluoride binding agents (calcium gluconate)

phenol -> not water soluble so requireds polyethylene glycol or glycerol

white phosphorous -> copper sulfate in solution

Question 20

what temperatures cause frostbite

Answer 20

sensory nerve dysfunction starts at 10C

ice crystals form -6- -15C - cellular injury begins here with intracellular dehydration

local inflammation, coagulation, resultant microvascular thrombosis and tissue necrosis after thawing

Question 21

management of frostbite

Answer 21

warm IV fluids

rapid rewarming with 40-42C water bath

TPA administration within 24 hours decreases rate of amputation

Question 22

pediatric effects of frostbite

Answer 22

young children - premature physeal closure 2/2 chondrocyte injury

older children - (>10yo) short digits, excess skin, joint laxity, degen joint changes

Question 23

late complications of frostbite in adults

Answer 23

cold intolerance, hyperhidrosis, trophic changes, raynaud phenomenon