Final - Toxicocolgy Flashcards
Initial things to do when a poisoning happens:
what things are used for stabilization?
ABC management (airway, breathing, circulation)
Vital signs
IV access
Oxygenation
Anion Ga
what is the equation?
(Na + K) - Cl - HCO3
Anion gap is present when the value of the equation is ______
is above 14
Normal reference range of osmolarity
285 - 300
Osmolar Gap = ________ - ________
measured osmolarity - calculated osmolarity
How to calculate osmolarity?
(2 x Na) + (BUN/2.8) + (Glu/18) + (EtOH/4.6)
Osmolar gap is present when ____
greater than 10
generic decontamination strategies when pt presents with a poisoning?
- Activated charcoal
- cathartics (accelerates defecation)
- gastric lavage (stomach pump)
- whole bowel irrigation (hella polyethylene glycol)
- hemodialysis
Activated Charcoal:
issues with it?
hard to administer (tastes AWFUL)
can not give when airway is unprotected (aspiration risk)
dose of activated charcoal?
1 - 2 GRAMS/kg (use actual body weight)
aka 50 - 100 grams in an adult
what drugs are examples of cathartics
magnesium citrate
sorbitol
complications from gastric lavage?
vomiting
aspiration
mechanical injury
whole bowel irrigation is good when what types of poisonings?
- sustained release products
- body packers/stuffers aka bags of cocaine were swallowed
- iron
- lithium
Whole bowel irrigation:
keep doing it until what?
go until there is CLEAR rectal effluent
dose for adults with whole bowel irrigation?
1000 - 2000 mL/HOUR!!!!!
Hemodialysis is good when what types of poisoning?
alcohols
lithium
salicylates
theophylline
Signs and symptoms of opioid toxicity
N/V Drowsiness PINPOINT pupils Hypotension bradycardia respiratory depression
drug to use when opioid overdose??
naloxone…
Naloxone:
use lower doses when _____
use higher doses when ____
use continuous infusions when ______
lower: when chronic opioid dependence to avoid withdrawal
higher: when if illicit drug use suspected (heroin, fentanyl and derivative)
continuous infusion: when longer acting opioid
APAP Toxicity:
what is a toxic dose?
7.5 - 15 grams
APAP Toxicity:
what are things that make someone a high risk candidate
- malnutrition/chronic illness
- concomitant CYP2E1 inducers (isoniazid)
- chronic alcohol ingestion
APAP Toxicity:
protective conditions?
acute alcohol ingestion
children
APAP Toxicity:
APAP gets converted to ______ (the toxic metabolite) by CYP ______
NAPQI; CYP 2E1
APAP Toxicity:
NAPQI –> _________ = necrosis
APAP-cysteine groups
APAP Toxicity- Timeline:
Peak AST/ALTs wont happen until how long after ingestion?
72 - 96 hours
APAP Toxicity - Timeline
____ and ____ rise first;
then ____ and ____ will rise
AST/ALT first
then bilirubin and PT
2 treatment options with APAP Toxicity?
NAC (N-acetylcysteine)
Activated charcoal
Which treatment option for APAP Toxicity is recommended within the first 4 hours of ingestion?
activated charcoal (get it before it absorbs!)
Which treatment option for APAP toxicity needs an APAP concentration obtained at least 4 hours AFTER ingestion? and why?
NAC
Why = because look at a nomogram to see if NAC would help or not
what nomogram is used to see if NAC is needed
Rumack-Matthew Nomogram
MOA of NAC?
glutathione analogue that can serve as an intracellular glutathione surrogate
how is NAC available (formulation wise)
PO and IV
How long to use NAC as treatment?
if IV = 21 hours
if PO = 72 hours
NAC is most effective within the first _____ hours of ingestion
8 hours
Salicylate Toxicity: electrolyte disturbance(s)?
Hypokalemia
Hypo/hyper natremia
Salicylate Toxicity - Concentrations:
Mild toxicity: > ____ mg/dL
Severe toxicity: > ____ mg/dL
mild: > 30
severe: > 80
Signs/Sxs of Salicylate Toxicity?
- N/V
- tinnitus and vertigo (seen at mild toxicity)
- decreased GI motility
- altered mental status (seen at severe toxicity)
- seizures (seen at severe toxicity)
- lethargy coma (seen at severe toxicity)
Salicylate Toxicity - Concentrations:
For analgesic properties: ___ - ___ mg/dL
For anti-inflammatory properties: ___ - ___ mg/dL
analgesic: 10 - 15
anti-inflame: 15 - 20
Salicylate Toxicity:
will see an ____ anion gap = metabolic _____
an elevated anion gap
metabolic acidosis
Salicylate Toxicity:
Antidote option?
sodium bicarbonate
MOA of Sodium bicarbonate with salicylate toxicity?
urine alkalinization
Indications for sodium bicarbonate in Salicylate Toxicity?
- Serum salicylate level > 30 mg/dL
- Anion gap metabolic acidosis
- altered mental status
Sedatives Toxicity: Signs and Symptoms?
similar to opioids (but NO pinpoint pupils)
- CNS depression
- Respiratory depression
- Hypotension
- Bradycardia
what is the drug that is competes with BZDs and the GABA binding site?
flumazenil
Flumanezil: used when in sedative toxicity?
used almost never…..
can cause seizures…..and then benzos cant be given to fix the seizure because the drug was given
TCA Toxicity – Signs and Symptoms?
- altered mental status
- hypotension
- tachycardia
- PROLONGED QRS
- seizures
- anticholinergic symptoms
how to treat sedative toxicity?
just supportive care – avoid FLUMAZENIL
TCA PK:
highly hydro- or lipo- philic
lipophilic
TCA Antidote?
Sodium Bicarbonate
MOA of Sodium Bicarbonate for TCAs?
increase of sodium gradient of poisoned sodium channels
Monitor what when giving sodium bicarbonate?
Serum pH 7.45-7.55
Monitor QRS/ECG
Antipsychotics:
1st gen: _____ antagonism
2nd gen: ________ antagonism
1st: D2 only
2nd: 5HT2A AND D2 antagonism
Antipsychotics Toxicity: Signs and Symptoms?
- hypotension
- tachycardia
- QT/QRS prolongation
- EPS (extrapyramidal symptoms)
- NMS (neuroleptic malignant syndrome)
- Sedation
what to give when extrapyramidal sxs present?
Benztropine
diphenhydramine
NMS symptoms?
Hyperpyrexia (fever of like 108!!)
altered mental status
“lead pipe” muscular rigidity
NMS:
how to treat?
stop offending agent (probably an atypical antipsychotic)
benzos
rapid external cooling
Dantrolene (muscle relaxant)
symptoms seen in serotonin syndrome?
altered mental status
autonomic instability
neuromuscular abnormalities
Serotonin syndrome: how to treat?
d/c agent
benzos
aggressive cooling
cyproheptadine
NMS or Serotonin Syndrome:
has a higher fever
NMS
NMS or Serotonin Syndrome:
will respond to cyproheptadine
serotonin syndrome
NMS or Serotonin Syndrome:
responds to bromocriptine
NMS
NMS or Serotonin Syndrome:
lasts > 24 hours
NMS
NMS or Serotonin Syndrome:
has DIFFUSE lead pipe rigidity
NMS
NMS or Serotonin Syndrome:
lower limbs are affected more than upper limbs
serotonin syndrome
Digoxin Toxicity: Signs and Symptoms:
Non cardiac??
N/V abdominal pain anorexia confusion VISION CHANGES!!! yellow halo
Digoxin Toxicity: Signs and Symptoms:
Cardiac??
Bradycardia
2nd/3rd degree heart block
arrhythmias
hyperkalemia
how to treat digoxin toxicity: stop \_\_\_\_\_\_ \_\_\_\_\_ management obtain \_\_\_\_\_\_\_ concentrations monitor \_\_\_\_\_\_ changes give \_\_\_\_\_\_\_\_\_\_\_ (if within 2 hours of ingestion) Consider administration of \_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_\_ is NOT effective
stop dig ABC management obtain dig serum concentrations monitor ECG changes give ACTIVATED CHARCOAL (if within 2 hours of ingestion) Consider administration of digibind Hemodialysis is NOT effective
Digibind dosing done how?
0.5 mg of dig binds to one vial of digibind
CCB or BB or both toxicity?
hypoglycemia
BB
CCB or BB or both toxicity?
hypotension/bradycardia
both
CCB or BB or both toxicity?
bronchospasms
BB
CCB or BB or both toxicity?
arrhythmias/cadiogenic shock
bot
CCB or BB or both toxicity?
hyperglycemia
CCB
CCB or BB or both toxicity?
pulmonary edema
CCB
CCB or BB or both toxicity?
metabolic acidosis
CCB
potential options for combating CCB or BB toxicity?
atropine calcium vasopressor therapy glucagon High dose insulin therapy lipid emulsion therapy
Calcium:
more effective for treating CCB toxicity or BB toxicity?
CCB
Calcium MOA for treating CCB toxicity?
Calcium opens Calcium channels = leads to myocardial contractility
what drugs are used for vasopressor therapy for BB toxicity?
epinephrine and norepinephrine (gotta use higher doses than normal to combat those beta receptors)
how does glucagon work for BB toxicity?
bypasses beta receptor and acts directly on Gs to stimulate conversion of ATP to cAMP
dosing for glucagon in BB toxicity?
minimum of 3 mg!!! 1 mg wont do the trick.
MOA of high dose insulin therapy for CCB and BB toxicity?
increased inotropy and increase intracellular glucose transport
dosing of insulin for CCB and BB toxicity?
like 1 unit/kg/hr IV
vs like normal insulin is 0.1 unit/kg/hr for DKA treatment
MOA of lipid emulsion therapy?
limits bioavailability of lipophilic medication by creating a lipid sink
Toxicology Tidbits Slide: (out of the 6 proposed methods for CCB/BB toxicity)
______ is not likely to be effective in either CCB or BB overdoses
atropine
Calcium Chloride vs gluconate:
______ has 3x more elemental Ca2+ in it but also has higher extravasation
Chloride
Toxicology Tidbits Slide: (out of the 6 proposed methods for CCB/BB toxicity)
______ therapy should be pre-medicated with anti-nausea meds
glucagon
Iron Toxicity Management:
Activated Charcoal: yay or nay?
Nay
Iron Toxicity:
Seen right away or in phases?
phases
day 2 - 3 see hepatoxicity
Iron Toxicity Management:
Whole bowel irrigation: yay or nay?
yay!
Iron Toxicity Management:
what is the iron antidote drug?
Deferoxamine (Desferal)
how does Deferoxamine work?
chelates iron and enhances renal elimination
which toxic alcohol is found in:
antifreeze, brake fluid/industry solvents
ethylene glycol
which toxic alcohol is found in:
rubbing alcohol, paint remover, cements, cleaners
isoproypyl alcohol
which toxic alcohol is found in:
windshield washer fluid, paint remover, copier fluid, some antifreeze/engine fuels
methanol
which toxic alcohol toxicity has an osmolar gap but NO anion gap
isopropyl alcohol
Ethylene glycol gets broken down to _____ acid which is the toxic metabolite
oxalic
For ethylene glycol toxicity:
give what to prevent it from getting metabolized to oxalic acid?
vitamins!! Thiamine; Mg2+; Pyridoxine
