An 80 kg male patient presented to the emergency with hypotension and you have been instructed to sta him on an inotrope at a dose of 10 mcg/kg/min. Each 5 mL amp of the drug contains 200 mg drug. You choose 2 ampules of the drug and decide to mix it with saline to make a 250 mL solution. What should be the flow rate of the drug solution to maintain the BP of the patient (assuming 16 drops = 1 mL)?
4 drops/min
8 drops/min
10 drops/min
16 drops/min
Ans: B. 8 drops/minA dosing of 10 mgm/kg/min of drug is requiredWeight = 80 kgTotal dose required = 10x80 = 800 mgm/min = 0.8 mg/minNow two 5 mL ls each containing 200 mg is diluted to a 250 mL solution.i.e. 400 mg is mixed in 250 mLConcentration of solution: 1 mL = 400/250 = 1.6 mg/mLNow, 1 mL 16 drops = 1.6 mg i.e. 16 drops contain 1.6 mgHence, 0.8 mg/min = 8 drops/min = 0.5 mL/min