Question of the Day

Add 1333 mg of 2% lidocaine to a 1L fluid bag, after removing the same volume (66.6 ml) of fluids from the bag first). Make sure to agitate the bag gently prior to administration.

Break down calculation questions into individual steps and then solve each step. Consider first converting the dosage into the correct units if they are not the same (e.g., if the dosage in the question is given in micrograms but the answer is requesting milligrams, do this conversion first).

Dosage of lidocaine in mg: 50 mcg/kg/min x 1 mg/1000 mcg = 0.05 mg/kg/min

Dosage of lidocaine for this dog: 0.05 mg/kg/min x 20 kg  = 1 mg/min

1 mg/min x 60 min/h = 60 mg/h

(60 mg/h / 45 ml/h) x 1000 ml/L = 1333 mg/L