A maintenance dose of 3% hypertonic saline after a 250 mL bolus is prescribed. If the maintenance rate is 50 mL/hour and the tubing has a drip factor of 15 gtt/mL, what is the drip rate in gtt/min?

A maintenance dose of 3% hypertonic saline after a 250 mL bolus is prescribed. If the maintenance rate is 50 mL/hour and the tubing has a drip factor of 15 gtt/mL, what is the drip rate in gtt/min?

• A. 12 gtt/min
• B. 13 gtt/min
• C. 15 gtt/min
• D. 10 gtt/min

Answer: (B)

To find the drip rate in drops per minute, convert the maintenance flow from mL/hour to drops per minute using the drop factor. Multiply the maintenance rate by the drip factor: 50 mL/hour × 15 gtt/mL = 750 gtt/hour. Then convert to minutes: 750 gtt/hour ÷ 60 minutes/hour = 12.5 gtt/min. Since we can’t deliver half a drop, round to the nearest whole drop, giving 13 gtt/min. The 250 mL bolus doesn’t affect this ongoing maintenance rate calculation; it’s broader context but not part of the drip-rate math.

To find the drip rate in drops per minute, convert the maintenance flow from mL/hour to drops per minute using the drop factor. Multiply the maintenance rate by the drip factor: 50 mL/hour × 15 gtt/mL = 750 gtt/hour. Then convert to minutes: 750 gtt/hour ÷ 60 minutes/hour = 12.5 gtt/min. Since we can’t deliver half a drop, round to the nearest whole drop, giving 13 gtt/min. The 250 mL bolus doesn’t affect this ongoing maintenance rate calculation; it’s broader context but not part of the drip-rate math.