Flashcards in EM Deck (51):
These 3 methods are ALWAYS wrong for ingestion overdose?
2) Forced diuretics
3) Cathartics (sorbitol)
What are 2 common presentations of altered mental status of unknown etiology in the ER? What is best initial treatment?
Tx: naltrexone & glucose
Do you need to give flumazenil to benzo overdose?
NO - this OD is NOT fatal and acute withdrawal can cause seizures!
What is always given to someone with a pill overdose?
When you don't know what to do in toxicology = give charcoal
What is toxic dose of acetaminophen?
If a clearly toxic amt of acetaminophen is ingested (8-10g), what is best initial treatment?
If acetaminophen has been OVER 24 hours, what is best initial therapy?
If amt of acetaminophen ingestion is unclear, what is next step?
Get a drug level
Can you use charcoal with N-acetylcysteine?
What 3 findings are seen with aspirin overdose?
2) Respiratory alkalosis (compensation for increased acid level)
3) Metabolic acidosis (aspirin blocks oxidative phosphorylation and results in increased anaerobic respiration = increased lactate = AG metabolic acidosis)
Treatment for aspirin overdose?
Alkalinize the urine --> increases rate of aspirin excretion
What are the 2 most severe finding in TCA overdose?
QT prolongation --> leading to arrhythmia
What other effects of TCA overdose can be seen?
Anti-ACh side effects --> dry mouth, constipation, urinary retention
Treatment of TCA overdose?
What is it's MOA?
TCA normally (-) fast Na channels in His-Purkinje system and myocardium. This causes the QRS prolongation and arrhythmias.
**NaHCO3 protects the heart by decreasing drug avidity for Na channels on the heart --> elevated Na concentration now increases the electrochemical gradient across cardiac cells and affects the ability of TCA to bind to fast Na channels
In caustic ingestions what are you NEVER supposed to give?
Acids or alkali to try and reverse what was initially ingested --> this will only cause extra damage from exothermic reaction
What damage is caused by caustic ingestions?
Mechanical damage to oropharynx, esophagus, stomach
*Look for perforation
Treatment for caustic exposure?
Flush out fluids w/ excess water
What scenarios should suggest CO poisoning?
Wood burning stove
CO effect on RBCs?
CO binds O2 to Hg so tightly that carboxyhemoglobin will NOT release O2 to tissues --> acts functionally like anemia
Patient presentation w/ CO poisoning or methemoglobinemia?
Cause of death from CO poisoning?
*Decreased O2 delivery to heart muscle --> lactic acidosis forms and tissue dies
*Metabolic acidosis results!
Can pulse oximetry be trusted with CO poisoning & methemoglobinemia?
What is pO2 level in CO poisoning & methemoglobinemia?
NORMAL (remains bound to hemoglobin)
Most accurate test for CO poisoning?
Best initial therapy in CO poisoning & methemoglobinemia?
Give 100% oxygen
*Severe disease treated with hyperbaric oxygen --> only if CNS symptoms, cardiac symptoms, or acidosis present
What drugs can result in methemoglobinemia?
Anesthetics (local - benzocaine, lidocaine)
Nitrites (nitroprusside, nitroglycerin)
Most accurate test for methemoglobinemia?
- Best INITIAL therapy?
- MOST effective therapy?
Best initial = 100% O2
Most effective = Methylene Blue
What is color of blood in CO poisoning? Methemoglobinemia?
CO poisoning = bright/cherry red
Methemoglobinemia = brown
Cyanosis + normal pO2 is what?
If someone has a head injury, what prophylactic medication must they be given? Why?
*Prevent stress ulcer formation in stomach --> Cushing ulcer
What substance should you consider with ingestion of windshield wiper fluid?
What s/s will you see?
**BLURRY VISION/BLINDNESS (formic acid is a degradation product of methanol that causes direct toxicity in optic nerve)
Tx: fomepizole (ADH inhibitor)
Gunshot wound to neck - what is best management?
Exploratory surgery AFTER most accurate knowledge of location and extent of injuries --> diagnostic studies should be done (angiogram, esophagogram, esophagoscope, bronchoscopy)
S/S of mercury poisoning?
Constricted visual fields
Tx: succimer, dimercaprol, penicillamine
What 2 harmful substances must you address in smoke inhalation injuries (fire victims)?
Cyanide & CO
Tx of cyanide: hydroxycobalamin or sodium thiosulfate or nitrites (induce methemoglobinemia)
With cyanide, why do you get high levels of LDH produced?
Cyanide inhibits ETC in mitochondria --> blocks ATP formation from oxidative phosphorylation --> cells have to utilize anaerobic metabolism
What finding on Xray can give you a clue to diaphragmatic rupture?
NG tube in the L chest cavity (follow trachea down and the NG tube will then coil up into the chest cavity)
3 complications of TCA overdose?
Treatment of choice for anaphylactic shock?
NEVER IV b/c of risk of arrhythmias!
Person is taking theophylline. What is it's metabolism? What drugs must you be careful taking with theophylline?
Cytochrome oxidase P450 in liver
**Meds that inhibit CYP450 will cause toxicity
- Cimetidine, Cipro, Erythomycin, Clarithromycin, Verapamil
S/S: CNS stimulation (HA, insomnia, seizures), arrhythmias
Patient had MVA. Despite 2L IV fluids, he remains at 80/40, HR of 120, and has JVD. Why is the cause? Next best step?
What OD is manifested by hypotension, bradycardia, AV block, and diffuse wheezing?
First line tx?
Tx for refractory hypotension and bradycardia?
B-blocker OD --> WHEEZING most specific
*can progress to cardiogenic shock
1st line: IV fluids + atropine (break the brady)
What is the timeframe to use charcoal in Acetaminophen OD?
Less than 4 hours after ingestion
Smoke inhalation exposure in people with HA, nausea, and abdominal discomfort - what do you suspect? What other exam finding is present? What is best initial test?
Pink-red skin coloring
Appropriate treatment for frostbite?
RAPID re-warming with WARM water --> immersed in warm water
45 yo homeless man presents to the ER with epigastric pain, vomiting, and being confused. He complains of vision loss and his fundoscopic exam shows optic disc hyperemia. His labs are:
Na - 136
K - 3.0
Cl - 93
HCO3 - 6
What is the cause of his symptoms?
*Metabolic acidosis with severe HCO3 loss
*Can lead to vision loss --> optic disc hyperemia
*Blurred vision, epigastric pain, vomiting, hyperemic optic disc
40 yo man is brought to ER in confused state. He attempted to OD, but doesn't remember the drug. He is drowsy with blurred vision. Temp is 100 but other vitals are normal. Mucus membranes are dry and pupils are 8mm b/l. Reduced bowel sounds heard and he has urinary retention. What is the agent?
Diphenhydramine (anti-histamine + anti-muscarinic)
Why are B-blockers CONTRAINDICATED in allergy testing?
If anaphylaxis occurs --> only treatment is EPINEPHRINE
*B-blockers will cause epinephrine to be ineffective!
What drug is CONTRAINDICATED in cocaine overdose with anginal pain?
*Cause unopposed alpha-agonist activity that can worsen the vasospasm!
What 2 conditions are B-blockers never the first treatment?
*Unopposed alpha stimulation would cause increased HTN/vasospasm