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Dosage calculation rn critical care proctored assessment 3.2
Total Questions : 30
Showing 10 questions, Sign in for moreA nurse is preparing to administer dopamine 5 mcg/kg/min to a client who weighs 198 lb. Available is dopamine 200 mg in dextrose 5% in water 250 mL. The nurse should set the IV pump to deliver how many mL/hr? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Convert the client's weight from pounds (lbs) to kilograms (kg):
Formula: Weight in kg = Weight in lbs / 2.2 lbs/kg
= 198 lbs / 2.2 lbs/kg
= 90 kg
Calculate the dopamine dosage in micrograms per minute:
Ordered dose: 5 mcg/kg/min
Client's weight in kg: 90 kg
Formula: Dosage (mcg/min) = Ordered dose (mcg/kg/min) × Client's weight (kg)
= 5 mcg/kg/min × 90 kg
= 450 mcg/min
Convert the dopamine dosage to micrograms per hour:
Conversion factor: 1 hour = 60 minutes
Formula: Dosage (mcg/hr) = Dosage (mcg/min) × 60 min/hr
= 450 mcg/min × 60 min/hr
= 27000 mcg/hr
Convert the dopamine concentration in the IV solution to micrograms per milliliter:
Available dopamine: 200 mg
Convert milligrams to micrograms: 200 mg × 1000 mcg/mg = 200000 mcg
Volume of solution: 250 mL
Formula: Concentration (mcg/mL) = Total micrograms / Total mL
= 200000 mcg / 250 mL
= 800 mcg/mL
Calculate the IV pump flow rate in mL/hr:
Formula: Flow rate (mL/hr) = Dosage needed (mcg/hr) / Concentration (mcg/mL)
= 27000 mcg/hr / 800 mcg/mL
= 33.75 mL/hr
Round the answer to the nearest tenth:
33.75 mL/hr rounded to the nearest tenth is 33.8 mL/hr.
A nurse is preparing to administer warfarin 5 mg PO to a client. Available is warfarin 2 mg tablets. How many tablets should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Ordered dose: 5 mg
Available strength: 2 mg per tablet
Calculate the number of tablets needed:
Formula: Number of tablets = Desired dose / Available dose per tablet
= 5 mg / 2 mg/tablet
= 2.5 tablets
A nurse is preparing to administer amphotericin B lipid complex 3.75 mg/kg via intermittent IV bolus to a client who weighs 167 lb. Available is amphotericin B lipid complex 300 mg in 300 mL of dextrose 5% in water. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies.)
Explanation
Calculation:
Convert the client's weight from pounds (lbs) to kilograms (kg):
Formula: Weight in kg = Weight in lbs / 2.2 lbs/kg
= 167 lbs / 2.2 lbs/kg
≈ 75.91 kg
Calculate the total dose of amphotericin B lipid complex needed:
Ordered dose: 3.75 mg/kg
Client's weight in kg: ≈ 75.91 kg
Formula: Total dose (mg) = Ordered dose (mg/kg) × Client's weight (kg)
= 3.75 mg/kg × 75.91 kg
≈ 284.66 mg
Determine the concentration of the available amphotericin B lipid complex solution:
Available amount: 300 mg
Volume of solution: 300 mL
Formula: Concentration (mg/mL) = Total amount (mg) / Total volume (mL)
= 300 mg / 300 mL
= 1 mg/mL
Calculate the volume of solution to administer:
Formula: Volume to administer (mL) = Desired dose (mg) / Concentration (mg/mL)
= 284.66 mg / 1 mg/mL
= 284.66 mL
Round the answer to the nearest whole number:
284.66 mL rounded to the nearest whole number is 285 mL.
A nurse is preparing to administer cyclosporine 5 mg/kg IV bolus to a client who weighs 143 lb. Available is cyclosporine injection 50 mg/mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Convert the client's weight from pounds (lbs) to kilograms (kg):
Formula: Weight in kg = Weight in lbs / 2.2 lbs/kg
= 143 lbs / 2.2 lbs/kg
≈ 65 kg
Calculate the total dose of cyclosporine needed:
Ordered dose: 5 mg/kg
Client's weight in kg: 65 kg
Formula: Total dose (mg) = Ordered dose (mg/kg) × Client's weight (kg)
= 5 mg/kg × 65 kg
= 325 mg
Determine the concentration of the available cyclosporine injection:
Available concentration: 50 mg/mL
Calculate the volume of cyclosporine to administer:
Formula: Volume to administer (mL) = Desired dose (mg) / Concentration (mg/mL)
= 325 mg / 50 mg/mL
= 6.5 mL
A nurse is preparing to administer lidocaine 2.5 mg/min to a client by continuous IV infusion. Available is lidocaine 1 g in dextrose 5% in water 250 mL. The nurse should set the IV pump to deliver how many mL/hr? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Calculate the total amount of lidocaine in milligrams:
Available lidocaine: 1 g
Conversion: 1 g × 1000 mg/g = 1000 mg
Determine the concentration of the lidocaine solution in milligrams per milliliter:
Total lidocaine: 1000 mg
Total volume of solution: 250 mL
Formula: Concentration (mg/mL) = Total milligrams / Total mL
= 1000 mg / 250 mL
= 4 mg/mL
Calculate the desired dose of lidocaine per hour in milligrams:
Ordered dose: 2.5 mg/min
Conversion: 2.5 mg/min × 60 min/hr
= 150 mg/hr
Calculate the IV pump flow rate in mL/hr:
Formula: Flow rate (mL/hr) = Desired dose per hour (mg/hr) / Concentration (mg/mL)
= 150 mg/hr / 4 mg/mL
= 37.5 mL/hr
Round the answer to the nearest whole number:
37.5 mL/hr rounded to the nearest whole number is 38 mL/hr.
A nurse is preparing to administer lactated Ringer's 100 mL/hr by continuous IV infusion. The drop factor of the manual IV tubing is 15 gtt/mL. The nurse should set the IV flow rate to deliver how many gtt/min? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Determine the total volume to be infused per hour:
Ordered rate: 100 mL/hr
Determine the drop factor of the IV tubing:
Drop factor: 15 gtt/mL
Calculate the total number of drops to be infused per hour:
Formula: Total drops per hour (gtt/hr) = Total volume (mL/hr) × Drop factor (gtt/mL)
= 100 mL/hr × 15 gtt/mL
= 1500 gtt/hr
Convert the flow rate to drops per minute:
Conversion factor: 1 hour = 60 minutes
Formula: Flow rate (gtt/min) = Total drops per hour (gtt/hr) / 60 min/hr
= 1500 gtt/hr / 60 min/hr
= 25 gtt/min
A nurse is preparing to administer nitroprusside 4 mcg/kg/min IV to a client who weighs 143 lb. Available is nitroprusside 50 mg in dextrose 5% in water 250 mL. The nurse should set the IV pump to deliver how many mL/hr? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Convert the client's weight from pounds (lbs) to kilograms (kg):
Formula: Weight in kg = Weight in lbs / 2.2 lbs/kg
= 143 lbs / 2.2 lbs/kg
≈ 65 kg
Calculate the desired dose of nitroprusside per minute in micrograms:
Ordered dose: 4 mcg/kg/min
Client's weight in kg: 65 kg
Formula: Dosage (mcg/min) = Ordered dose (mcg/kg/min) × Client's weight (kg)
= 4 mcg/kg/min × 65 kg
= 260 mcg/min
Calculate the desired dose of nitroprusside per hour in micrograms:
Conversion factor: 1 hour = 60 minutes
Formula: Dosage (mcg/hr) = Dosage (mcg/min) × 60 min/hr
= 260 mcg/min × 60 min/hr
= 15600 mcg/hr
Determine the concentration of the nitroprusside solution in micrograms per milliliter:
Available nitroprusside: 50 mg
Convert milligrams to micrograms: 50 mg × 1000 mcg/mg = 50000 mcg
Total volume of solution: 250 mL
Formula: Concentration (mcg/mL) = Total micrograms / Total mL
= 50000 mcg / 250 mL
= 200 mcg/mL
Calculate the IV pump flow rate in mL/hr:
Formula: Flow rate (mL/hr) = Desired dose per hour (mcg/hr) / Concentration (mcg/mL)
= 15600 mcg/hr / 200 mcg/mL
= 78 mL/hr
A nurse is preparing to administer 0.9% sodium chloride 250 mL IV to infuse over 30 min. The drop factor of the manual IV tubing is 10 gtt/mL. The nurse should set the manual IV infusion to deliver how many gtt/min? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Determine the total volume to be infused:
Total volume: 250 mL
Determine the total infusion time in minutes:
Infusion time: 30 minutes
Determine the drop factor of the IV tubing:
Drop factor: 10 gtt/mL
Calculate the total number of drops needed:
Formula: Total drops (gtt) = Total volume (mL) × Drop factor (gtt/mL)
= 250 mL × 10 gtt/mL
= 2500 gtt
Calculate the flow rate in drops per minute (gtt/min):
Formula: Flow rate (gtt/min) = Total drops (gtt) / Total time (minutes)
= 2500 gtt / 30 minutes
≈ 83.33 gtt/min
Round the answer to the nearest whole number:
83.33 gtt/min rounded to the nearest whole number is 83 gtt/min.
A nurse is preparing to administer 0.9% sodium chloride 250 mL IV to infuse over 3 hr. The drop factor of the manual IV tubing is 10 gtt/mL. The nurse should set the IV flow rate to deliver how many gtt/min? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Determine the total volume to be infused:
Total volume: 250 mL
Determine the total infusion time in minutes:
Infusion time: 3 hours × 60 minutes/hour = 180 minutes
Determine the drop factor of the IV tubing:
Drop factor: 10 gtt/mL
Calculate the total number of drops needed:
Formula: Total drops (gtt) = Total volume (mL) × Drop factor (gtt/mL)
= 250 mL × 10 gtt/mL
= 2500 gtt
Calculate the flow rate in drops per minute (gtt/min):
Formula: Flow rate (gtt/min) = Total drops (gtt) / Total time (minutes)
= 2500 gtt / 180 minutes
≈ 13.89 gtt/min
Round the answer to the nearest whole number:
13.89 gtt/min rounded to the nearest whole number is 14 gtt/min.
A nurse is preparing to administer lidocaine 4 mg/min by continuous IV infusion. Available is lidocaine 1 g in dextrose 5% in water 250 mL. The nurse should set the IV pump to deliver how many mL/hr? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
Calculation:
Calculate the total amount of lidocaine in milligrams:
Available lidocaine: 1 g
Conversion: 1 g × 1000 mg/g = 1000 mg
Determine the concentration of the lidocaine solution in milligrams per milliliter:
Total lidocaine: 1000 mg
Total volume of solution: 250 mL
Formula: Concentration (mg/mL) = Total milligrams / Total mL
= 1000 mg / 250 mL
= 4 mg/mL
Calculate the desired dose of lidocaine per hour in milligrams:
Ordered dose: 4 mg/min
Conversion: 4 mg/min × 60 min/hr = 240 mg/hr
Calculate the IV pump flow rate in mL/hr:
Formula: Flow rate (mL/hr) = Desired dose per hour (mg/hr) / Concentration (mg/mL)
= 240 mg/hr / 4 mg/mL
= 60 mL/hr
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