Chemical and physical injury Flashcards
Who is at risk of ethylene glycol poisoning?
children
suicide attempt
alcoholic
What are the key toxic metabolites of ethylene glycol?
oxalate: generates calcium oxalate crystals that deposit in the kidney, can lead to renal failure
glycolate: contributes to anion gap metabolic acidosis
Where in the brain does CO preferentially bind cytochrome enzymes?
globus pallidus, pars reticularis of substantia nigra
Describe CO toxicity
- tissue hypoxia due to decreased available oxygen
- binding to cytochrome enzymes= impairment of cellular respiration
_______ causes a bright red coloration to tissues
carboxyhemoglobin
Describe the bioavailability of different forms of cocaine administration
IV> intranasal, smoking> swallowed
rectal insertion thought to be effective
Describe the major metabolites of cocaine
Principle metabolite is benzoylecgonine.
Combination with ethanol → coca ethylene/ ethylcocaine
Norcocaine in people with activated hepatic P450s (ex chronic alcoholic)
Methylecgonidine is a metabolite unique to smoked form
____ is a metabolite of cocaine that has a stronger biological activity and longer half life than parent cocaine
ethylcocaine/ cocaethylene
Describe the biochemical mechanisms of cocaine toxicity
cellular reuptake blockage of norepinephrine, dopamine, serotonin, and blockage of sodium channel conductance
Premature _______ is a key concern related to chronic cocaine use
coronary atherosclerosis
Define abrasion
epidermal injury where the outer layers of skin are removed due to frictional forces.
types: linear, brush type (road rash), impact, pattern
Define contusion
- area of localized tissue and vascular damage caused by blunt trauma
- confluence of non-epithelial microscopic tissue lacerations
Define laceration
tearing of tissue caused by shearing or crushing injury
What differentiates a laceration vs an incision
Lacerations: adjacent tissue abrasion, tissue bridging, adjacent contusion
Define incision
tissue disruption due to contact with a sharp edged object
Define stab
sharp force injury that is deeper than it is wide
Describe three types of gunshot wounds in terms of range of fire
- contact: soot and powder within wound, abrasion collar, charring of wound edges
- intermediate: far enough away that there is no soot, may still have a small abrasion (stippling, tattooing)
- distant: no soot or powder, no stippling
Describe the rule of 9s for body surface area affected by a burn
- head is 9%
- each upper extremity is 9%
- front of each leg is 9% the back of each leg is 9%
- top front of the torso is 9%, bottom front of torso is 9%
- top front of the back is 9%, bottom front of back is 9%
The genital region is 1%.
_______ is the most important factor related to electrical injuries
amerage
How do electrical injuries cause death?
paralysis of respiratory muscles
cardiac arrhythmia
internal charring
Describe the appearance of electrical burns
white chalky appearance with raised border, central crater
microscopically- denaturation of collagen, elevation and blistering of epidermis, distortion and linear streaming of nuclei
usually palmar or plantar skin
A fern-like pattern of skin burning is characteristic of injury from ______
lightning
What groups are at increased risk of heat stroke?
elderly very young cardiopulmonary disease users of MDMA use of anti-cholinergic drugs- decreased vasodilation/ inhibition of sweating
What is malignant hyperthermia?
syndrome of hypermetabolism (tachycardia, tachypnea, and muscle spasms) usually triggered by the induction with halogenated anesthetics
