Renal toxicology EM Flashcards
Osmolar gap equation
Calculated osmolatity = 2(Na+ concentration) + ((glucose/18) + BUN/2.8))
Serum osmolarity from labs - calculated osmolarity
If above is greater than 10 = something else that is not normal is in the body
- usually ethanol
if wanting to determine if it is ethanol, can add EtOH/4.6 to the calculated equation
“DUMPS ALE” mnemonic
Reminds you of the most common causes of a increased anion gap acidosis
DKA Uremia Methanol Paracetamol Salicylates
Alcohol
Lactic acidosis
Ethylene glycol
SLIME TP mnemonic
Reminds you of the most common indications for hemodialysis
Salicylates Lithium INH/isoniazid Methanol Ethylene glycol
Theophylline
Phenobarbital
ME DIE mnemonic
Reminds you of the most common causes for an osmolar gap
Methanol
Ethylene glycol
Diuretics
Isopropanol
Ethanol
What is the pH correction rate with pCO2 changes?
Every 10 mmHg drop in pCO2, pH goes up 0.08
Why does alkalization of urine become so importaint for salicylate OD?
In acidic conditions, H+ ions bind to ASA to from toxic metabolites.
- in alaklized conditions, H+ ions dissociated from ASA compounds and allow them to be excreted.
What does uncoupling oxidative phosphorylation mean in ASA overdose?
ASA uncoupled oxidative phosphorylation which shuts down aerobic respiration and upregulates anaerobic/lactic respiration
- leads to metabolic acidosis with lactic acidosis and anion gap
How do we alkaline urine?
Dextrose and sodium bicarbonate IV bolus. Also correct glucose as needed.
- 3 sodium bicarbonate w/ 1 dextrose 5%
Also must give patient potassium replacements
- hypokalemia causes reabsorption of potassium via K+/H+ exchangers. This makes it impossible to alkaline urine if H+ keeps getting pumped into lumen
Toxicity of alcohol from least to greatest
EtOH < Isopropyl < Ethylene glycol < Methanol (most dangerous)
3 types of ketone bodies
Acetone
- all alcohols
AcetoAcetic acid
- all alcohols
B-hydroxybuterate
- most common in most alcohols and DKA, however isopropanol does NOT produce this!
What must you give patients with ethylene glycol poisoning?
pyridoxine and thiamine
- exhausts these stores very quickly so if you dont replenish this the CNS depression wont ever recurrent
also causes refractory seizures if you DONT give
Why does methanol causes afferent pupillary defects?
Provides direct toxicity to the optic nerve
Isoniazid
** big caveat = someone who is from out of country and is being treated for TB without knowing the exact medication and shows status epilepticus = isoniazid toxicity until proven otherwise**
- *MUST give pyridoxine/B6 before any other treatments, including diazepam**
- 5 grams of these two must be given
- this is the only way the status epilepticus will respond
when do we intubate patients?
If GCS is below 8
- “8 = intub8”
- or they just straight up cant breath
Life threatening causes of ataxia in children
1) Cerebellar/frontal tumors
2) Intracranial bleeding
- usually presents with headache
3) strokes
4) Sepsis
5) Toxic exposure
1-3 = get MRI
