Poisoning and Overdose Answers 257delusion of superhuman strength and nystagmus. (b)When cocaineuse is
stopped or when a binge ends, a crash follows almost immediately. This is
accompanied by a strong craving for more cocaine, fatigue, lack of plea-
sure, anxiety, irritability, sleepiness, and sometimes agitation or extreme
suspicion.(e)Opioid withdrawal initially presents with drug craving,
yawning, rhinorrhea, and piloerection and progresses to nausea, vomiting,
diarrhea, hyperactive bowel, diaphoresis, myalgias, arthralgias, anxiety, fear,
and mild tachycardia.
231.The answer is a.(Goldfrank et al, pp 980-988.)Ananion gapis the
difference between unmeasured anions (eg, proteins, organic acids) and
unmeasured cations (eg, potassium, calcium, magnesium). The anion gap
can be calculated from the formula:
Anion gap = [Na+]−[HCO 3 + Cl−]The normal anion gap is approximately 6 to 10 mEq/L. The cause of
increased anion gap is frequently remembered by the mnemonic MUD
PILES:
M:methanol, metformin P:paraldehyde
U:uremia I:iron, INH
D:diabetic ketoacidosis L:lactate
E:ethylene glycol, ethanol
S:salicylateOur patient’s anion gap is (141) −(101 + 14) = 26.
Themeasured serum osmolarityperformed by the laboratory is mea-
sured by a depression in the freezing point or an elevation in the boiling
point of the solution. If there is an increase in low molecular weight mole-
cules, such as acetone, methanol, ethanol, mannitol, isopropyl alcohol, or
ethylene glycol, the osmolarity increases more than what is calculated from
the regular serum molecules.
The formula to calculate serum osmolarity is:
Serum Osm (mOsm/kg) = 2[Na+] + glucose/18 + BUN/1.8 + EtOH/4.6The difference between the actual measured osmolarity and the calcu-
lated osmolarity is the osmol gap (measure −calculated).
Our patient’s osmol gap is (352) −(292) = 60. When the osmol gap is
greater than 50 mOsm/L, it should be considered nearly diagnostic of toxic