Ch 9 Injury by Physical Agents

Question 1

clinical significance of thermal burns depends on

Answer 1

depth of burns
% of body surface involved
internal injuries caused by the inhalation of hot and toxic fumes
promptness and efficacy of therapy, especially fluid and electrolyte management and prevention or control of wound infections

Question 2

superficial burns (1st)

Answer 2

confined to epidermis

Question 3

partial thickness burns (2nd)

Answer 3

injury to dermis

Question 4

full thickness (3rd)

Answer 4

extend to subcutaneous tissue, damage to mm tissue underneath the subcutaneous tissue (4th)

Question 5

greatest threat to life in burn pts

Answer 5

shock, sepsis, respiratory insufficiency

Question 6

systemic inflammatory response syndrome

Answer 6

shift of body fluids into the interstitial compartments

Question 7

most common bacteria associated w/ burns

Answer 7

pseudomonas aeruginosa

Question 8

morphology full thickness burns

Answer 8

white or charred, dry, painless

Question 9

morphology partial thickness burns

Answer 9

pick or mottled w/ blisters and painful

Question 10

heat cramps

Answer 10

loss of electrolytes via sweating

Question 11

heat exhaustion

Answer 11

MOST COMMON

due to failure of the CV system to compensate for hypovolemia due to dehydration

Question 12

heat stroke

Answer 12

high ambient temperatures, high humidity, exertion

rise in core body temp over 40 degrees C

Question 13

malignant hyperthermia

Answer 13

mutation in the RYR1 gene

heat stroke like rise in core temp and mm contractures following exposure to common anesthetics

Question 14

direct effect of hypothermia

Answer 14

mediated by physical disruption w/in cells by high salt concentrations caused by the crystallization of intra and extracellular water

Question 15

indirect effects of hypothermia - slow chilling

Answer 15

vasoconstriction and increased vascular permeability

Question 16

indirect effect of hypothermia - sudden chilling

Answer 16

vasoconstriction and increased viscosity of the blood, edema only after temp beings to return

Question 17

main determinants of biologic effects of ionizing radiation

Answer 17

rate of delivery
field size 
cell proliferation 
oxygen effect and hypoxia 
vascular damage

Question 18

lymphocytes 1-2

Answer 18

granulocytopenia, lymphopenia

1 day to 1 week

Question 19

bone marrow 2-10

Answer 19

leukopenia, hemorrhage, hair loss, vomiting

2-6 weeks

Question 20

small bowel 10-20

Answer 20

diarrhea, fever, electrolyte imbalance, vomiting

5-14 days

Question 21

brain greater than 50

Answer 21

ataxia, coma, convulsions, vomiting

1-4 hours

Question 22

morphology - ionizing radiation

Answer 22

changes in chromosomes
nuclear swelling, condensation and clumping of chrom.
giant cells w/ pleomorphic nuclei
cytoplasmic swelling
vascular changes and interstitial fibrosis