Chemical Trauma

Question 1

Define toxicology.

Answer 1

Field of science that helps us understand the harmful effects that chemicals, substances, or situations can have on people, animals and the environment.

Question 2

Define forensic toxicology.

Answer 2

The application of toxicological principles, theory, and methods to cases before the court.

Question 3

What is a chemical?

Answer 3

Any substance that is produced or purified in a reaction that involves changes to atoms and molecules.

Question 4

List the 6 different classifications of chemicals as outlined in class.

Answer 4

Organic, inorganic
Benign, healthy
Legal, illegal

Question 5

What is a benign chemical?

Answer 5

Chemical that produces no effects

Question 6

Give examples of sources of healthy chemicals.

Answer 6

Food, nutrients, prescription drugs

Question 7

Give four examples of poisons/environmental chemicals.

Answer 7

Hydrogen sulfide
Hydrogen cyanide
CO
Cyanide

Question 8

Give examples of chemicals of abuse.

Answer 8

Depressants
Stimulants
Hallucinogens

Question 9

What is chemical trauma?

Answer 9

Trauma caused either directly or indirectly by the application of chemical agents to tissues

Question 10

Give examples of direct chemical trauma.

Answer 10

Tissue destruction (e.g., burns)

Question 11

Give examples of indirect chemical trauma.

Answer 11

Asphyxia, long-term structural changes, infection

Question 12

What causes direct destruction of tissues?

Answer 12

Application of strong bases, strong acids, elemental metals, phenol…

Question 13

What type of chemical causes the most damage?

Answer 13

bases

Question 14

What are 5 mechanisms of direct chemical trauma?

Answer 14

Red/ox
Corrosion
Protoplasmic disruption
Vesicants
Desiccants

Question 15

What do vesicants do? What can this eventually lead to?

Answer 15

Bring fluid where it doesn’t belong
Blistering, ischemia –> necrosis

Question 16

What do desiccants do?

Answer 16

Pull fluid out of cells

Question 17

What is an injury typically associated with stimulants?

Answer 17

Holes in tissue, specifically roof of mouth

Question 18

How can chemicals lead to infection?

Answer 18

via introduction route (needle, inhalation) due to tissue destruction or disruption

Question 19

Other than via introduction route, how else can chemicals lead to infection? Give an example.

Answer 19

Introduction of a pathogen via the agent.
Ex: aspergillosis infection from inhaled cocaine

Question 20

What is asphyxia?

Answer 20

loss of oxygen to tissues either because body cannot take in oxygen or cannot make use of the oxygen it does have.

Question 21

What causes asphyxia? 6

Answer 21

Tissue destruction
Metabolic derangement
Oxygen sequestration
Congestion
Inflammation
Action on respiration centres of the brain

Question 22

What part of the brain houses the respiration centres?

Answer 22

brainstem - medulla oblongata

Question 23

Describe this image of alveoli.

Answer 23

Cocaine entered the lungs.
Red = bleeding due to hemorrhage
pink = hemosiderosis, release of chemicals into extracellular space.

Question 24

Describe what is seen in this image of alveoli.

Answer 24

scar tissue due to prolonged exposure to cocaine.

Question 25

Why is scar tissue in the lungs harmful?

Answer 25

Limits expansion of lungs, oxygen intake

Question 26

Is aortic dissection direct or indirect chemical trauma?

Answer 26

Indirect

Question 27

What is aortic dissection?

Answer 27

Separation of vessel layers causing cell walls to be weakened

Question 28

What types of drugs can cause aortic dissection? Give examples.

Answer 28

Stimulants Cocaine, amphetamine

Question 29

Other than chemical, what is another type of trauma that can cause aortic dissection? Give examples.

Answer 29

Blunt force trauma MVA, physical assault

Question 30

What does asbestos exposure lead to?

Answer 30

Pleural plaques

Question 31

What are pleural plaques?

Answer 31

Chemical itself lays on pleura

Question 32

What do pleural plaques do to pleural cells? What can this cause?

Answer 32

Changes in DNA, leading to mesothelioma

Question 33

What are the 5 factors affecting the severity of chemical trauma?

Answer 33

Chemical agent Time of exposure Tissue exposed/penetrated Deliivery method Quantity and concentration

Question 34

What is crack lung?

Answer 34

Heavily scarred lung tissue due to cocaine use

Question 35

When can crack lung become fatal?

Answer 35

Can lead to death in the long term or as little as 48 hours after crack use

Question 36

What does the lethality of crack lung depend on?

Answer 36

Susceptibility and dose

Question 37

Why is crack lung an issue?

Answer 37

Lung tissue affected cannot exchange oxygen.

Question 38

What is the issue if asbestos enters the lung?

Answer 38

It cannot be cleared over time.

Question 39

What are the two types of developmental windows identified in class?

Answer 39

Acute and chronic

Question 40

What does acute chemical use indicate?

Answer 40

Overdose

Question 41

What can an overdose lead to?

Answer 41

Depression of function, specifically of brainstem

Question 42

What are the consequences of brainstem function depression?

Answer 42

Heart rate, respiration, balance

Question 43

Give an example of drug that can be overdosed on.

Answer 43

Fentanyl, can cause lots of damage at low concentrations

Question 44

What does chronic chemiical use refer to?

Answer 44

Long-term

Question 45

what can chronic chemical use lead to? What can this cause?

Answer 45

Receptor sensitivity changes (tolerance) Leading to cell death

Question 46

What types of loss can lead to cell death?

Answer 46

Structural loss (i.e., chemical damaging cell wall) Loss of function

Question 47

Give an example of a condition leading to cell death.

Answer 47

Alcoholic neuropathy

Question 48

Describe the identifiable effects on imaging of alcoholic neuropathy

Answer 48

Loss of white matter, massive ventricle expansion

Question 49

What affects of medium-term alcohol abuse can occur on the liver?

Answer 49

fatty liver disease (reversible)

Question 50

What affects on the liver can long term alcohol abuse lead to?

Answer 50

cirrhotic liver

Question 51

What is the developmental window that alcohol use is most likely to lead to fetal alcohol syndrome.

Answer 51

0-8 weeks

Question 52

Why are fetuses so susceptible to FAS during the first 8 weeks of development?

Answer 52

Rapid development and organ formation during this time, susceptible to birth defects.

Question 53

Describe the effects of alcohol on the fetus following the first 8 weeks.

Answer 53

Neurological impairment is possible By third trimester fetus can redirect blood supply and spare brain

Question 54

Describe the discriminating features of FAS.

Answer 54

Narrowed eyelids/sockets Flat midface Short nose Indistinct philtrum Thin upper lip

Question 55

Describe the associated features of FAS.

Answer 55

Low nasal bridge Epicanthal folds Minor ear anomalies Small chin

Question 56

List the 9 learning disorders associated with FAS.

Answer 56

Dyslexia Dyscalculia Dysgraphia Dyspraxia Spelling problems Auditory processing disorder Visual processing disorder Verbal processing disorder ADHD

Question 57

what are potential issues with delivery method in chronic use ?

Answer 57

infection risk collapsed vessels

Question 58

What is pharmacokinetics?

Answer 58

dose - concentration vs. time

Question 59

what is pharmacodynamics?

Answer 59

effect vs. concentration

Question 60

What is an effective dose?

Answer 60

Desired therapeutic/recreational effect Act on desired tissue with desired effect

Question 61

What are two pharmacodynamic complications associated with overdoses?

Answer 61

Effect is too strong Effect is on the wrong tissue

Question 62

Using SSRIs, give an example of what would occur at an effective dose.

Answer 62

Act on desired tissue (brain) Desired effect = serotonin reuptake

Question 63

Using SSRIs, give an example of what would occur at an overdose.

Answer 63

Too strong: respiratory depression Wrong tissue: cardiac events