Question

A solution containing 500,000 units of polymyxin B sulfate in 10 mL of sterile water for injection is added to 250 mL of 5% dextrose injection. T he infusion is to be administered over 2 hours. If the administration set delivers 15 drops/mL, at what rate, in drops per minute, should the flow be adjusted to administer the infusion over the designated time interval?

Answer 1

Step-by-step explanation:

It is given that the total units of polymixn B silfate are present as follows.

(10 + 250) ml = 260 ml

Therefore, total volume necessary to inject the whole volume is as follows.

`260 * 15` drops

= 3900

It is given that total time required to inject the solution is 2 hours. Converting it into minutes as follows.

`2 hrs * (60 min)/(1 hr)`

= 1200 minutes

Hence, rate of injection is calculated as follows.

Rate of injection (r) =
`\frac{\text{total drops}}{\text{total time}}`

r =
`(3900)/(120)`

= 32.5 drops/min

Thus, we can conclude that the rate of injection is 32.5 drops/min.