Urine color is often under-appreciated in working up a patient’s clinical status (especially in the ICU and OR). “Highlighter” yellow urine is often seen in patients on B vitamin complexes (it’s a water-soluble vitamin, and your body doesn’t need 1,000% of the daily requirement, lol), red/brown urine can be related to hemoglobin/myoglobin breakdown (hemolysis, rhabdo, etc.), orange urine is often seen in patients on rifampin (an antibiotic) or phenazopyridine (an analgesic dye for the GU tract), magenta after CyanoKit, and of course “purple urine in porphyria.”
Green urine is an often benign sign which I’ve most commonly seen after the intraoperative administration of methylene blue for refractory vasoplegia and rarely after propofol usage (due to phenol-based metabolites). It’s important to remember that in the latter case, the presence of green urine does NOT mean renal function is impaired, or propofol is inadequately metabolized. Remember that propofol’s metabolism exceeds that of the hepatic metabolism since it can also be broken down in the lungs, kidneys, etc. Other causes for green urine include other dyes (i.e., indigo-blue), long-standing obstructive jaundice, infections (i.e., Pseudomonas), and other medications (TCAs, H2 blockers, NSAIDs).
Drop me a comment below with questions and your thoughts/experiences!