Posions Flashcards
sources of carbon monoxide
endogenous
incomplete conbustion of fossil fuels, old cars
exposure to methylene chloride
some drugs - phenytoin, phenobarb
is carbon monoxide a routine analysis
no
elimination of carbon monoxide
unchanged by the lungs
mechanism of carbon monoxide poisoning
binds to hemoglobin causing tissue hypoxia
CO level 30-40% sx
sever headache, weakness, dizziness, nv, collapse
CO level 40-50% sx
retinal hemorrhage
increased respiration
over 50% CO sx
convulsions
coma
death
who is most susceptible to CO poisoning
infants those with lung disease CV disease elderly anemia
treatment of CO poisoning
remove person from source of CO
hyperbaric oxygen
problems with interpretation in CO poisoning
whole blood - has to be whole blood bc binds to RBC
putrefaction - byproducts given off that interfere with analysis bc same UV spectrum
fire victims may have to use liver or kidney tissues bc blood coagulated
forms of cyanide
hydrogen - cololess gas or blue white liquid
salts - white crystalline powder
sources of cyanide
normal metabolism cigarette smoking insecticides electroplating industry dyeing, printing, photgraphy combustion of N containing compounds - synthetic furniture cyanogenic glycosides
mechanism of cyanide toxicity
enzymatic poison attacks the cytochrome system
prevents oxygen utilization at the cellular level
results in metabolic asphyxiation (no oxygen)
acute cyanide toxicity sx
giddiness stiff lower jaw rapid slow breathing muscle twitching palpitation cyanosis convulsion coma death due to resp arrest *brain and heart most sensitive
chronic cyanide toxicity sx
dizzy weak congestion of lungs conjunctivitis loss of appetite weight loss mental deterioration
deathly concentrations of cyanide
> 270ppm immediately fatal
180 - 10min
135 - 30min
110 - 1 hr
treatment of cyanide poisoning
body can detoxify on its via rhodanese enzyme
but can be sped up by adding an exogenous source of sulfur
agents used in cyanide poisoning
amyl nitrite - given at scene
sodium nitrite
sodiom thiosulfate - best one
how does sodium nitrite work
turns hemoglobin into methemoglobin which combines with iron cyanide to form cyanomethemoglobin so cyanide is tied up not causign damage
how does sodium thiosulfate work
combines with cyanide to form thiocyanate
interpretation of cyanide
whole blood
problems with postmortem cyanide detection
enzymes and bacteria produce cyanide
what are inhalants
breathable chemical vapors that producs psychoactive effects
volatile solvents, aerosols, anaesthetics, volatile nitrites
reason for widespread use of inhalents
low cost
ready available
legal
methods of inhalant exposure
inhalation
oral ingestion
skin contact
what is sniffing
directly inhaling from container or heated pan or from a piece of clothing soaked with solvent
what is huffing
holding solvent soaked rag over face and breathing in through mouth
what is bagging
spraying or pouring the solvent into a plastic bag holding over mouth and nose and inhaling from the bag
typical abuser of inhalants
young
male
underpriveleged unstable home
poor student with high rate of absenteeism
ppl likely exposed to inhalants
doctors nurses dentist hair stylist painter dry cleaners
stimulant phase of sniffing
euphoria excitement release of inhibitions floating sensation delusions of grandeur and invincibility lasts 15-30min
depressant phase of sniffing
drowsy slowed reflex stupor bizarre thoughts hallucination similar to alcohol intoxication lasts 1-2hrs
indicators of inhalant use
pungent chemical odor excessive nasal secretion red watery eyes, dilated pupil, rapid involuntary eye movement double vision ringing in ears vivid dreams hallucination slow slurred speech white powdery ring of dried glue around mouth and nose paint stains on body or clothing drooling, sores aroudn mouth paraphenalia with traces of paint/glue
inhalant absorption
vapors enter bloodstream directly from lungs
stored in fat tisssues and slowly released back into the blood
inhalant distribution
rapidly distributed to brain and liver
inhalant metabolism
some metabolized and excreted by kidneys
other eliminated unchanged via lungs
long term effects of sniffing
fatigue chronic headache dizzy depression irritable loss of concentraion loss of appetite tremor liver kidney and brain damage
dependence associated with inhalant use
psychological dependece
tolerance
no physiological dependence but some develop tremors
what is sudden sniffing death
follows strenuous exercise or stress after several deep inhalations of sniff
caused b yheart failure resulting from severely irregular heartbeat (arrythmia)
associated with halogenated hydrocarbons
