Emergency Medicine Flashcards
from USMLE
Typical antipsychotics: side effects and risks?
Neuroleptic malignant syndrome. Sx: EPS, sweating, tachycardia, muscle rigidity, hyperthermia. Typical > atypical. Tx: bromocriptine and dantroline, diazepam
How do you treat a benzodiazepam overdose?
flumenazil 200ug c 1-2minutes. Max 3mg/hour. MOA: GABA antagonist.
Difference between megaloblastic anemia due to folate deficiency or B12 deficiency?
B12 deficiency will cause neurological symptoms; folate deficiency will not
Most common infection in burn victims?
Psudomonas
Normal urine output/hr
30cc stable patient; 50cc in a trauma patient
Symptoms of increased ICP?
Cushing reflex: bradycardia, hypertension, abnormal breathing
Also fixed & dilated pupils, vomiting, papilledema
tx: IV mannitol
Tx for cardiogenic shock?
Dobutamine (beta-1 agonist)
Tx for malignant hyperthermia?
Dantroline (muscle relaxer; decreases excitation coupling by acting as an antagonist on the ryanodine receptor, decreasing intracellular Ca+ concentration)
Sx of cardiac tamponade?
Pulsus paradoxus; Beck’s triad (increased JVP, hypotension, decreased heart sounds)
Difference between subdural and epidural hematoma on CT?
Subdural: cresent-shape lesion on CT, blown pupil
Epidural: Biconvex (diamond-oval), blown pupil
Recall that dura mater -> arachnoid -> pia mater, from outside to inside
How to differentiate between hemothorax and pneumothorax with percussion?
Hemothorax: dullness
Pneumothorax: resonance
What is the definition of hemodynamic instability in a trauma patient?
SBP <90mmHG
To estimate SBP without a sphygmomanometer:
carotid 60mmHg
femoral 70mmHg
radial 80mmHg
If a trauma patient is stabilized and then becomes suddenly unstable, what is at the top of your ddx?
air embolism
tx: have them lie in LLD, give oxygen, ER
If a pt with chest trauma suddenly has a new diastolic murmur and hoarseness, what do you suspect?
aortic dissection
hoarseness is caused by impingement on the recurrent laryngeal nerve
risks for dissection include EDS, Marfan’s, and syphilis
aortic disruption can be caused by breaks in the 1st rib, scapula, sternum; these are strong bones and are very hard to break. if a pt comes in with any of these bones broken, suspect internal injuries
All patient w LOC get what imaging done?
CT head w/o contrast
Symptoms of a fat embolism?
patient with a long-bone fracture suddenly has fever, tachycardia, tachypnea, conjunctival hemorrhage and petechiae
What is a flail chest?
3+ ribs broken in at least 2 places so pieces of the bone are not connected to any of the rest of the ribs
In blunt abdominal trauma, what is the most common injury?
#1 injury to the spleen #2 liver If the injury is handlebar trauma in a child, most common is pancreas injury, then duodenum (sx of this include epigastric pain with bilious vomiting)
Most common site of diaphragm rupture?
L side (liver protects R)
Acute abdomen lesser-known ddx
Main categories: perforation, obstruction, inflammation, ischemia
sickle cell anemia crisis, porphyria, DKA, leukemia, pneumonia, lead poisoning, black widow bite
+bHCG in a shock patient is what?
ruptured ectopic pregnancy until proven otherwise
Acute abdomen with blood pr is what?
mesenteric ischemia until proven otherwise
usually elderly, history of AAA or Afib, or **cocaine user
Risks for biliary colic?
4 Fs (female, fat, forty, fertile)
Ischemic colitis is most common in who?
patient with a history of MI, stroke, or CAD (other blood vessel disease predisposes)
When is abdominal CT with contrast indicated?
appy, IBD, diverticulitis, AAA, cancer
Appy management?
PAIN (pain relief, antibiotics, IV fluids, NPO)
Abx need to have both anaerobic and Gm(-) coverage i.e.
cefazoline + metronidazole
cefazoline is bactericidal: it binds certain proteins and causes bacteria to lyse because they break down their own walls
metronidazole is a nitroimidazole and is also bactericidal. it disrupts DNA synthesis.
Difference in appearance between 1, 2, and 3 degree burns?
1: only epidermis. epidermis is red and intact, no blisters (i.e. sunburn)
2: extends into dermis. painful blisters (i.e. boiling water)
3: painless, white, charred (i.e. fire)
In any burn involving a fire: assess for smoke inhalation (CO risk) or exposure to burning textiles (CN- risk)
What are the causes of PEA?
5Hs & 5Ts hypoxia hypothermia hypovolemia hydrogen ions (acidosis) hypo/hyperkalemia
tablets (drug OD) tamponade (cardiac) tension pneumothorax thrombosis (coronary) thrombosis (pulmonary embolism)
tx: CPR, epinephrine, +/- vasopressin (if due to hypovolemia), find cause from list above and tx the cause
DO NOT DEFIB A PT IN PEA/ASYSTOLE
let the AED decide, but it will probably opt not to
proceed with CPR anyway and hopefully this will bring back a rhythm
What is the first symptom of hemorrhagic shock?
changes in heart rate. blood pressure will not change until >1.5L of blood has been lost
Treatment for Vfib?
CPR, defibrillator, epinephrine, amiodarone
Treatment for Afib?
If unstable: cardioversion
If stable: beta-blockers or diltiazem (CCB) for rate control
Anticoagulants if Afib persists for >48 hours
Can throw clots otherwise; Afib confers 5x risk of embolic stroke
90% of cardiac thrombi originate in the left atrial appendage → stroke!
Transesophogeal Echo to dx
At what temperature is someone experiencing hyperthermia?
Body temperate > 104 F
<95 F you experience shivering
< 89.6 F confusion and arrhythmia
<82.4 comatose
you can’t declare a pt dead until they are warm (>89.6 F)
Tx for bradycardia?
atropine, dopamine, epinephrine, pacemaker
Tx for anthrax exposure?
doxycycline (broad-spectrum; fucks with RNA; binds 30s ribosomal unit) or ciprofloxacin (quinolone)
Bacillus anthracis is a Gram+, endospore-forming, rod-shaped bacterium. Endospore are resistant to heat, drying, bleach etc
One of few bacteria to synthesize a protein capsule
Anthrax is a common disease of livestock
Epinephrine concentrations for IM vs. IV?
IM or SQ: 1:1,000 0.3-0.5mg q 5m up to 3x
(can give up to 1g IM at once)
IV: 1:10,000 0.1-0.2mg q 5m
When giving an IV, when does the patient run the risk of phlebitis?
450-600 msom (or whatever) possible, >600 definitely
Definition of hypo, iso, and hypertonic solutions?
<250 hypotonic
250-375 isotonic
>375 hypertonic
Sx of poisonous spider bite?
Black widow: muscle spasms, mimics acute abdomen with no rebound tenderness: Tx: antivenin
Brown recluse: necrosis, flu sx, DIC. Tx: cold compress, dapsone (CIed in G6PD), debridement
Sx of poisonous scorpion bite?
Neuromuscular toxicity with cranial nerve dysfunction, seizure activity, autonomic dysfunction, and impaired breathing.
Tx: Antivenin if available; if not, benzodiazepines and analgesics
Sx of poisonous snake bite?
Necrosis, distributive shock, DIC.
Tx: Antivenin (CroFab). Keep affected limb below the heart.
DO NO use compression bands, tourniquets, etc
How do you treat an animal bite by something with large, sharp teeth (large dog, other human etc)?
Amoxicillin/clavulanic acid
Do NOT suture closed
Monitor for signs of deep infection including osteomyelitis as well as rabies and tetanus (ask after immunization status, bring in animal if possible to test for rabies)
How do you treat a rodent bite?
Low risk for infection, no risk for rabies
Wild rodents may have leptospiridosis (more commonly affects dogs than humans)
Local wound care should be sufficient
How do you handle a shellfish sting (i.e. cone snail)?
Can cause severe necrotizing fasciitis, hemorrhagic bullous lesions, increased risk in patients with liver disease including hemochromatosis
IV doxycycline and ceftriaxone, emergent surgical debridement
Symptoms and causes of CO poisoning?
HA, confusion, flu-like symptoms
Can be due to inhalation of smoke, car exhaust, BBQ smoke or fuel, and old appliances especially in areas that aren’t well-ventilated
Management of CO poisoning?
Test serum carboxyhemoglobin with co-oximetry. Normal is <5% for most patients and <10% for smokers. O2 sat will be normal (pulse ox will read carboxyhemoglobin as normal hemoglobin). Give 100% O2. If >25% patient needs hyperbaric oxygen.
Sx and causes of methemoglobinemia?
Hypoxemia after exposure to an oxidizing agent that ranges ferrous iron (Fe2+) -> ferric iron (Fe3+) which impairs O2 transportation
Dt exposure to local anesthetic, nitrite, or dapsone
Cyanosis with chocolate-looking blood on blood draw
Use co-oximetry to test methemoglobin (pulse ox and PaO2 will be WNL).
Tx of methemoglobinemia?
Tx: methylene blue
Sx and causes of arsenic poisoning?
pesticides, pressure-tx wood, contaminated well water
sx: garlic breath, V, watery diarrhea, prolonged QT interval, hypo or hyperpigmentation if chronic + peripheral neuropathy
Tx of arsenic poisoning?
Tx: dimercaprol
How do you diagnosis cyanide poisoning?
Clinical suspicion
the test is slow and will not result in time to save the pt
Sx include ha, weakness, N/V, confusion
Tx = decontamination and hydroxycobalamin if known exposure
When do you give charcoal for a poisoning victim?
Give charcoal if ingestion happened <2h ago
Exceptions: lithium, iron, lead, hydrocarbons, EtOH, lethargic patients (can aspirate it)
Pump their stomach if its been <1h only
Ipecac is antiquated; DONT USE; may cause double the harm coming back up
