Variable area flowmeters consist of a tapered, vertically-oriented tube with the smallest diameter at the base and largest at the top. As a result, the cross-sectional area of the tube changes based on height....

Sodium is the primary cation (positive-charged ion) in the extracellular space. Therefore, dilutional hyponatremia can occur if free water is added to the extracellular space from fluid shifts and infusions. Let's look at this basic...

Olanzapine (Zyprexa) is a second-generation ("atypical") antipsychotic that can be administered as an oral disintegrating tablet (ODT) or intramuscular (IM) injection. Like most antipsychotics, olanzapine works by blocking postsynaptic dopamine (D2) and serotonin (5HT2)...

Gentamicin is an intravenous, intramuscular, and topical aminoglycoside bactericidal antibiotic that works by interfering with bacterial protein synthesis. By binding the 30S subunit of the bacterial ribosome, proteins are improperly translated leading to bacterial...

Promethazine (Phenergan) is an oral, intramuscular (IM), rectal, and intravenous (albeit with caution!) phenothiazine derivative that is both a first-generation antihistamine (H1 receptor antagonism) and a weak typical antipsychotic (D2 receptor antagonism). It also...

Loop diuretics like furosemide (Lasix) and bumetanide (Bumex) block the reabsorption of sodium, potassium, and chloride in the thick ascending limb of the loop of Henle. This interferes with concentrating the renal medulla, and...

Polymyxin B is a "last-line" antibiotic primarily used to treat hospital-acquired gram-negative infections that are resistant to essentially all other conventional antibiotics. As an intensivist, I've had to use polymyxin B for two very...

Aorta-esophageal fistula is an abnormal communication between the aorta and esophagus leading to life-threatening exsanguination via the GI tract. This can be caused by procedures (e.g., weeks following cardiac arrhythmia ablation), malignancy, foreign body,...