Environmental Factors Flashcards
(142 cards)
1
Q
How can mechanical trauma produce damage?
A
- cutting, tearing, or crushing tissues
- severe blood loss
- interruption of blood or air supply
2
Q
What are skin and soft tissue terminology (mechanical trauma)?
A
- incision
- abrasion or scrape
- laceration
- puncture
- contusion
3
Q
incision
A
clean cut by a sharp object
4
Q
abrasion or scrape
A
superficial tearing away of epidermal cells
5
Q
laceration
A
jagged tear, often with stretching of the underlying tissue
6
Q
puncture
A
deep tubular wound produced by a sharp, thin object
7
Q
contusion
A
- bruise caused by disruption of underlying small blood vessels
- commonly involves skin but may also involve internal organs
8
Q
What are bone and tendon terminology (mechanical trauma)?
A
- fracture
- acute musculotendinous injuries
- chronic musculoskeletal injuries
9
Q
fracture
A
break of a bone
- closed or compound
- often bleeding into surrounding muscle, other tissues
10
Q
What are acute musculotendinous injuries?
A
torn muscle fibers, ruptured tendons, dislocated joints
11
Q
What are chronic musculoskeletal injuries?
A
- osteoarthritis of joints
- thickening of tendon sheaths (e.g. repetitive strain)q
12
Q
What are mechanical trauma causes of death?
A
- hemorrhage into body cavities
- fat embolism from bone fractures
- ruptured viscera
- secondary infection
- renal shutdown (acute tubular necrosis especially myoglobin casts arise from crush injury of skeletal mm.)
13
Q
What are blunt force injuries to the head?
A
head injury
- brain damage with possible skull fracture
- brain laceration
- brain contusion
14
Q
What can cause brain damage with possible skull fracture
A
- cerebral trauma
2. intracranial hemorrhage
15
Q
What is a brain laceration?
A
fracture–> penetrating injury by skull fragments
16
Q
What is a brain contusion?
A
-may occur at point of impact (coup injury) or opposite side of brain (contrecoup injury)
17
Q
blunt force abdominal injury can result in
A
- contusion
- rupture of spleen or liver sometimes with severe hemorrhage
- rupture of the intestine can result in peritonitis
18
Q
blunt force thoracic injury
A
rib fracture
-penetration into pulmonary parenchyma
or thoracic wall vessels
19
Q
rib fracture penetration into pulmonary parenchyma
A
pneumothorax
- air in the pleural cavity
- lung collapse
- shift of mediastinum and circulatory disturbances
20
Q
What can penetration into thoracic wall vessels lead to?
A
hemothorax
-hemorrhage in the pleural cavity
21
Q
knife and stab wounds
A
- incisions or puncture wounds
- result in highly variable consequences depending on site of injury
22
Q
entrance wound on gunshot
A
usually smaller and rounder than exit wound (can be smaller than bullet due to skin elasticity
23
Q
exit wound of gunshot
A
- can be significantly larger than the bullet due to tumbling of the bullet
- usually irregular or stellate rather than round
24
Q
contact wound of gunshot
A
- there may be burning around the margins of the wound (abrasion ring)
- over the skull, and other areas with skin closely overlying bone, may demonstrate stellate appearance due to gases from the gun undermining skin margins
25
close range gunshot wounds (20" or less)
- demonstrate unburned powder
- particles in skin tattooing or stippling
- deposits of soot on skin
26
long range gun wound
- usually round or oval
- clean margins
- no evidence of stippling or fouling
27
What are the effects of mechanical trauma?
inflammation= always present
necrosis=results in loss of tissue
hemorrhage= blood loss leading to compression, asphyxia, coma
infection= organisms can proliferate in wound, decontamination, debridement necessary to prevent infection
thrombosis= clot leading to infarction or embolism
shock= severe trauma-> circulatory disturbance-> renal and respiratory failure, brain damage
28
chronic low grade mechanical traumaeffects
- results in proliferation of tissue
- ex. epulis fissuratum
- epithelial and fibrous hyperplasia
- proliferation of tissue in the vestibule
- due to poor fitting denture with an extended flange area
29
1st degree burns (partial thickness burns)
- hyperemia without significant epi. damage
| - generally heal without intervention
30
2nd degree burns (partial thickness burns)
- blistering (bulla), destruction of epidermis
- slight damage to underlying dermis
- generally heal without intervention
31
3rd degree burns (full thickness burns)
- damage to epidermis, dermis, and dermal appendages
- skin and underlying tissue often charred and blackened
- often requires skin grafting
32
superficial burns
- 1st and 2nd degree burns
- epithelium can regenerate
- painful but not serious
33
deep burns
- 3rd degree burns
- all epithelium destroyed
- dermis and appendages damaged
- heals by scarring
- may result in contractures of joints and disfigurement
34
thermal injury from heat complications
- inhalation of smoke or toxic fumes
- hypovolemia
- curling ulcer
- infection
35
inhalation of smoke or toxic fumes
pulmonary or systemic damage
36
hypovolemia
fluid and electrolyte loss
37
curling ulcer
acute duodenum ulcer associated with severe burns
38
infection
- most common cause of late fatalities
| - most frequent organism pseudomonas aeruginosa
39
death from thermal injury
- dependent on percentage of body burned
- mortality
- 40% of body burned (death possible)
- 60% of body burned (death 100%)
40
What can cause early death from thermal injury?
fluid loss which can cause shock
41
What can cause late death from thermal injury
due to infection in weeks or months
42
treatment of thermal injury
extensive grafting
43
frostnip
prolonged immersion in cold--> damaged endothelium with edema and swelling (leakage of fluid)
44
frostbite
-may be localized and usually affects exposed areas (fingers, toes, earlopes, or nose)
45
-severe, prolonged frostbite may result in
- erythema and pruritus
- intracellular ice crystals
- intravascular thrombosis
- sometimes local gangrene
- may be generalized and lead to death
46
electrical injury (burns and shock)
-electric current passes through an individual (electric circuit completed)
47
mortality
current passing through brain or heart
48
morbidity
- cessation of activity in cardiorespiratory brain centers
- cardiac arrest and arrhythmias
- small cutaneous burns with blister (vesicle, bulla) formation- point of entry or exit of the electric current
- at times burns may be severe
49
UV radiation injury
- mostly sun damage to skin and eyes
- acute injury of skin
- chronic injury of skin
50
acute injury of skin
- sunburn (1st degree)
- onset of delayed vascular dilation--> erythema
- often superficial desquamation
- severe cases--> blister formation
51
chronic injury of skin
- collagen and elastic tissue damage
- epithelial changes
- cosmetic damage-wrinkling
- precancerous lesions- actinic keratosis
- cancerous-basal cell carcinoma, squamous cell carcinoma, melanoma
52
ultraviolet irradiation injury mechanism
absorption of UV light by DNA--> DNA fractures or changes in sequences
53
irradiation injury examples
- x-ray, radioactive waste, nuclear disasters
| - short wavelength, high frequency (x-rays and gamma rays, particulate radiation (electrons, protons, and neutrons))
54
transfer of energy to molecules leads to ionization
-molecules reactive and capable of doing
-damage
damage cells--> toxic free radicals
55
toxic free radicals
affect vital cell components (DNA and intracellular membranes)
56
damage to the DNA (ionizing radiation)
- direct action (hit) on vital molecule
- indirect action (ionization of water--> free radicals--> damage to vital molecules)
- damage repairable but very slow
57
ionizing radiation
some damage directed to cell membranes and others to cell organelles
58
ionizing damage dependent on
total dose, rate of delivery, and type of tissue irradiated
59
sequelae of localized radiation (ionizing radiation)
- skin and mucosa changes
- pulmonary changes
- gastrointestinal inflammation/ulceration
- hematopoietic alteration
60
skin and mucosa changes
- dermatitis (mucositis)
- ulceration
- vaculitis
- malignancies
61
pulmonary changes
- acute-similar to ARDS (acute respiratory syndrome)
- chronic- septal fibrosis, bronchiolar metaplasia, hyaline thickening of blood vessel walls
-
62
hematopoietic alterations
bone marrow depression or leukemia
63
neoplasia
- localized radiation sequellae
| - neoplasia: myeloid leukemias, cancers of bone, skin, thyroid, lung or breast
64
severe + generalized ionization radiation
- whole body-nuclear disasters
- severe CNS injury (Capillary damage)
- GI mucosal denudation
- Acute bone marrow failure
65
morphologic changes in IR with Brain
1. adult-resisistant
| 2. embryonic- destruction of neurons and glial cells (weeks to months)
66
morphologic changes in IR with Skin
1. erythema, edema (Early)
2. dyspigmentation (wks to mos)
3. atrophy, cancer (mos to yrs)
67
morphologic changes in IR with lungs
1. edema
2. ARDS
3. interstitial fibrosis (mos. to years)
68
morphologic changes in IR with lymph nodes
1. acute tissue loss
| 2. atrophy and fibrosis (late)
69
morphologic changes in IR with gastrointestinal tract
1. mucosal injury (early)
2. ulceration (early)
3. fibrosis of wall (late)
70
morphologic changes in IR with gonads
1. testis early (destruction)
2. ovaries early (destruction)
3. atrophy and fibrosis (late)
71
morphologic changes in IR with blood and bone marrow
early
1. thrombocytopenia
2. Granulocytopenia
3. anemia
4. lymphopenia
72
IR radiosensitivity of specialized cells
1. tissues with a high mitotic rate and /or rapid turnover are most susceptible
2. lympocytes- earliest blood cells to be affected
73
IR- radiosensitivity of specialized cells
1. most sensitive- regularly actively divide
2. intermediate sensitive
3. resistant-division ceases after fetal development
74
most sensitive (IR radiosensitivity)-regularly actively divide
1. lymphoid
2. hematopoietic
3. germ
4. gastrointestinal mucosa
5. rapidly dividing tumor cells
75
intermediate sensitive (IR radiosensitivity)
1. fibroblasts
2. cells of endothelium
3. elastic tissue
4. salivary glands
5. eye
76
resistant (IR radiosensitivity) -division ceases after fetal development
1. bone
2. cartilage
3. muscle
4. CNS
5. Kidney
6. liver
7. most endocrine glands
77
50 Gy (5,000 rads) to any one body region
- no severe or lethal consequences
- may be minor changes: therapeutic radiation to the jaw may cause obliterative endarteritis to the salivary glands and bone
78
3 Gy (300 rads) to the whole body
20-50% death
79
10 Gy (1,000 rads) to the whole body
100% death
80
hematopoietic system syndrome
206 Gy--> 2 week latency--> system fails--> death at about 3 weeks post irradiation
81
cerebral system syndrome
10Gy--> 1hr latency--> death in 1 day post irradiation
82
less than .5 Gy=mutation (whole body radiation)
- no systemic effects
| - may cause mutation ion stem cells, predisposing to neoplasia
83
.5-2 Gy= radiation sickness (whole body irradiation)
- lethargy, nausea, and anorexia
- transiet drop in neutrophils and lymphocytes
- not fatal
84
2-6 Gy= haemopoietic syndrome (whole body radiation)
- bone marrow hypoplasia
- leukopenia, thrombocytopenia, and developing anaemia after 2 weeks
- death in about 50% of cases caused by infection due to impaired immunity
85
3-10 Gy=gastrointestinal syndrome
-death of epithelial cells in gut
-hair loss
nausea and diarrhea within hrs of exposure
-dose: 3-4 Gy gut function may recover after month
86
10 Gy= cerebral syndrome (whole body radiation)
- heamorrhagic necrosis
- deathin within hours of exposure
- convulsions, delirium, and coma
87
effects on fetus
| .25 Gy or more from A-bomb
- reduced head size
- mental and growth retardation
- ther anomalies
88
effects on fetus
| -IR 14 days gestation
-.25 Gy needed for anomalies to occur
| =3 Gy can result in abortion
89
how many Gys are there in a diagnostic X-ray ?
.005
| -anomalies in fetus are unlikely
90
acute alcoholism
- affects CNS
- associated with automobile and industrial incidents; suicide
- acute intoxication may cause death
91
chronic alcoholism
- fatty change, alcoholic hepatitis and cirrrhosis (Scar)
- acute and chronic pancreatitis
- gastritis, gastric ulcers, poor absorption
- oral, pharyngeal, laryngeal, esophageal and gastric carcinomas (Especially when combined with tobacco use)
- alcoholic (dilated) cardiomyopathy; arrythmias, low outpu
92
chronic alcoholism
- aspiration pneumonia
- myopathy-muscle weakness
- peripheral neuropathy
- cerebral dysfunction
93
Wernicke-Korsakoff syndrome (alcholic encephalopathy)
- thiamine deficiency-mediated
- often associated w/ hemorrhagic necrosis of mamillilary bodies
- ataxia, confusion, ophthalmoplegia, nystagmus
- memory loss and confabulation
94
fetal alcohol syndrome
- microcephaly
- mental retardation
- facial and cardiac defects
95
active smoking (tobacco substance abuse)
cancer associations
- lung cancer and bronchogenic carcinoma
- acute myeloid leukemia
- cervical, kidney, pancreas, stomach, lip, and oral cavity
96
other condition associated with active smoking
- pneumonia, abdominal aortic aneurysm, cataracts
- periodontitis
- myocardial infarction slide 57
97
What conditions are associated with active smoking?
*periodontitis
*saliva of smokers accelerates growth of oropharngeal cancers (destroys antioxidants)
-penumonia, abdominal aortic aneruysm, cataracts
-myocardial infarction
bronchitis and emphysema
-systemic atherosclerosis, stroke
-pregnancy complications
98
What is tobacco abuse associated with?
- squamous cell carcinoma of they larynx
- squamous cell and small cell bronchogenic carcinoma
- transitional cell carcinoma (urinary bladder)
- chronic obstructive pulmonary disease
- atherosclerosis
- other vascular occlusive diseases
- -->Buerger's disease
99
What are 4 common smoking complications?
- cancer of the lung
- chronic bronchitis emphysema
- myocardial infarction
- systemic atherosclerosis
100
What are the risk factors for oral squamous cell carcinoma?
smoking +alcohol--> synergistic affect
101
What does Cocaine (Crack) do to your mood?
- mood elevation
- irritability
- anxiety
- depression---> suicide
102
What does Cocaine do to your myocardium/
- Increased myocardial irritability--> fatal arrythmias
| - myocardial infarction
103
How does cocaine cause a hemorrhage?
hypertension-> cerebral infarction/hemorrhage
104
what does intranasal cocaine use cause?
- nasal congestion
- ulceration
- septal perforation
105
What does the free base prep of cocaine cause
burn injury
106
What can cocaine lead to?
- Viral (HIV or Hep B)
- bacterial (infective endocarditis) infection from IV use-- Bacterial often right side of the heart valves are involved
- muscle necrosis
- epileptic seizures
- respiratory arrest
- newborn of addicted mothers have multiple small cerebral infarcts
107
how is heroin usually administered?
IV
108
What are the consequences of heroin?
- physical dependence w/ withdrawal syndromes
- infections (HIV, HEP B, INfective endocarditis)
- ARDS
- DEATH (respiratory/cardiac arrest, pulmonary edema)
109
what is the most common direct chemical cause of death, accidental or suicidal?
carbon monoxide
110
How does CO inhibit the capacity of hemoglobin to function as an oxygen carrier?
1. hemoglobin has an infinity for CO that is 200x greater than that for Oxygen
2. oxyhemoglobin is displaced by carboxyhemoglobin
111
What are early symptoms of CO?
headache and dizziness
112
How can CO be fatal?
-irreversible hypoxic injury--> possible death
113
What neurons of the brain are most vulnerable with CO?
basal ganglia, lenticular nuclei, cortical gray areas
114
What happens when CO becomes fatal?
- cherry red skin colo
| - blood,viscera, and mms
115
What are the routes of administration with lead?
1. inspiration (breathing) especially automotive emissions
| 2. ingestions especially lead based paint
116
What does lead do to RBCs?
RBC changes like hypochromic microcytic anemia and basophilic stippling
117
What is hypochromic microcytic anemia?
- deficient heme synthesis mediated by the inhibition of delta-aminolevulinic acid (ALA) dehydratase and decreased incorporation of iron into heme
- accumulation of ALA and erythrocyte protoporphyrin--> protoporphyrinemia, porphyrinuria, and ALA acidurea
118
What can toxic amounts of lead lead to?
-encephalopathy, neuropathy, fanconi syndrome, lead line in ginigva, increased radiodensity of the epiphyses of long bones
119
Where does mercuric chloride come from and what can it lead to?
1. ingested seafood
| 2. acute focal gastrointestinal ulceration and severe renal damage
120
What leads to widespread necrosis and calcification of the proximal convoluted tubules
mercuric chloride
121
what leads to chronic poisoning like CNS symptoms, psychosis, paranoia, and irritability?
mercuric chloride
122
What develops drug-resistant organisms mediated by plasmids carrying specific drug resistant genes?
antibiotics
123
what causes fatal aplastic anemia?
antibiotics
124
what is fatal aplastic anemia
idiosyncratic reaction to chloramphenicol
125
What act as haptens to stimulate antibody production like immune complex diseases (polyarteritis nodosa)
sulfonamides
126
What can sulfonamides lead to?
1. cystallization of sulfonamides within the renal collecting system--> calculi with obstruction, infection or both
2. bone marrow failure
3. acute, self limited hemolytic anemia induced inpersons with erythrocyte glucose-6-phosphate dehydrogenase deficiency (G6PD)
127
What leads to Gastroduodenol bleeding?
aspirin
128
How does aspirin make the gastroduodenum bleed?
- gastric or peptic ulcer
| - inhibition of platelet cyclooxygenase--> thromboxane A2 deficiency and impaired platelet plug formation
129
What is reye syndrome?
following acute, febrile, firal inlles
130
What follows acute, febrile, viral ilness in child?
reye syndrome
131
What is Reye syndrome associated with
aspririn use
132
What happens to the liver in reye syndrome?
microvesicular fatty change (liver) and encephalopathy
133
What are the toxic effects of cancer chemotherapeutic drugs?
1. hair loss (alopecia)
2. gastrointestinal erosions/ulcerations
3. bone marrow failure
134
What can cancer chemotherapeutic drugs cause?
acute leukemia and other malignancies
135
What are adverse drug reactions involved blood dyscrasias?
aplastic anemia
136
What are adverse drug reactions involved with the skin?
hives, eruptions, erythema
137
What are adverse drug reactions involved with the cardiac?
arrythmias and cardiomyopathy
138
What are adverse drug reactions involved with the renal system?
inflammation and necrosis
139
What are adverse drug reactions involved with the liver?
fatty change or necrosis
140
What are adverse drug reactions involved with the lung?
asthma
141
What are adverse drug reactions involved systemically?
severe allergy or anaphylaxis
142
What are adverse drug reactions involved with the CNS?
respiratory depression
