Advance IV Therapy Module Example 1

1 1 Advance IV Therapy Module Example 1 A patient is to receive Lidocaine at 3mg/min. Supplied is a one liter bag of D5W containing Lidocaine 4g. Calculate the infusion rate in mL/hr. First, identify the doctor s order. Doctor s order = min3mg This is also known as the dose. Second, identify the dose on hand (DOH). Dose on hand = mLg10004 Supplied is Lidocaine 4g in a one liter (1000mL) bag of D5W. This can be written as mLg10004. Now solve for the infusion rate in mL/hr using dimensional analysis. Doctor s order Conversion DOH Conversion Wanted Quantity min3mg x mgg10001 x gmL41000 x hr1min60 = 45 The infusion rate would be 45mL/hr. Remember to set up your problem so that the proper units cancel. 2 Example 2 A diabetic is to receive an infusion of insulin at 12 units/hr. The nurse prepares a 250mL bag of NS with 100 units of regular insulin.

2 What is the infusion rate in mL/hr? First, identify the doctor s order. Doctor s order = hrunits12 This is also known as the dose. Second, identify the dose on hand (DOH). Dose on hand = mLunits250100 Supplied is 100 units of regular insulin in a 250mL bag of NS. This can be written as mLunits250100. Now solve for the infusion rate in mL/hr using dimensional analysis. Doctor s order DOH Wanted Quantity hrunits12 x unitsmL100250 = 30 The infusion rate would be 30mL/hr. Remember to set up your problem so that the proper units cancel. 3 Example 3 The doctor orders Heparin at 1800 units/hr. Available is 25,000 units in 250mL of solution. Calculate the infusion rate in mL/hr. First, identify the doctor s order. Doctor s order = hrunits1800 This is also known as the dose. Second, identify the dose on hand (DOH). Dose on hand = mLunits250000,25 Supplied is 25,000 units in 250mL of solution.

3 This can be written as mLunits250000,25. Now solve for the infusion rate in mL/hr using dimensional analysis. Doctor s order DOH Wanted Quantity hrunits1800 x unitsmL000,25250 = 18 The infusion rate would be 18mL/hr. Remember to set up your problem so that the proper units cancel. 4 Calculating a dose based on weight. Example 4 The doctor orders Nipride 3mcg/kg/min to keep SBP < 140mmHg. The pharmacy supplies this in a 250mL bag of D5W that contains 50mg of the drug. The patient weighs 56kg. Compute the dosage in mcg/min and the infusion rate in mL/hr. First, identify the doctor s order. Doctor s order = min3kgmcg The doctor s order is given as 3mcg/kg/min. This can be written as min3kgmcg. Second, identify the dose on hand (DOH). Dose on hand = mLmg25050 Supplied is a 250mL bag of D5W that contains 50mg of the drug.

4 This can be written as mLmg25050. Third, identify the patient s weight. Patient s weight = 156kg The patient s weight given is 56kg. This can be written as 156kg. Now let s first solve for mcg/min using dimensional analysis. Doctor s order Patient s weight Wanted Quantity min3kgmcg x 156kg = min168mcg The dose for this patient would be 168mcg/min. Remember to set up your problem so that the proper units cancel. 5 Now that you know the dose for the patient, calculate the infusion rate in mL/hr using dimensional analysis. Patient s dose Conversion DOH Conversion Wanted Quantity min1168mcg x mcgmg10001 x mgmL50250 x hr1min60 = = 50 hrmL The infusion rate would be 50 mL/hr. Remember to set up your problem so that the proper units cancel. To check your answer, back solve. You can do this by first solving for mg/hr using the dose calculated for the patient.

5 Dose Conversion Conversion = Wanted Quantity min1168mcg x mcgmg10001 x hr1min60 = hrmg = 10 hrmg Using the dose for the patient based on their weight, they should receive 10 mg/hr. To finish back solving, solve for mg/hr using the calculated infusion rate and the DOH. DOH Infusion Rate = Wanted Quantity mLmg25050 x hrmL50 = 10hrmg Using the DOH and the infusion, the patient should receive 10 mg/hr. Since both answers are equal to each other, your calculation is correct. 6 Example 5 A patient weighing 252 pounds is to begin an infusion of dopamine at 5mcg/kg/min. The drug is supplied in a 250mL bag of NS that contains 400mg. What is the dosage in mcg/min and the infusion rate in mL/hr? First, identify the doctor s order. Doctor s order = min5kgmcg The doctor s order is given as 5mcg/kg/min.

6 This can be written as min5kgmcg. Second, identify the dose on hand (DOH). Dose on hand = mLmg250400 Supplied is a 250mL bag of NS that contains 400mg. This can be written as mLmg250400. Third, identify the patient s weight. Patient s weight = 1252lb The patient s weight given is 252lb. This can be written as 1252lb. Let s first convert the patient s weight from pounds to kilograms. Patient s weight Conversion Wanted Quantity 1252lb x = kg Now let s solve for mcg/min using dimensional analysis. Doctor s order Patient s weight Wanted Quantity min5kgmcg x = = 573minmcg 7 The dose for this patient would be 573 mcg/min. Remember to set up your problem so that the proper units cancel. Now that you know the dose for the patient, calculate the infusion rate in mL/hr using dimensional analysis.

7 Patient s dose Conversion DOH Conversion Wanted Quantity min573mcg x mcgmg10001 x mgmL400250 x hr1min60 = 21 hrmL The infusion rate would be 21 mL/hr. Remember to set up your problem so that the proper units cancel. To check your answer, back solve. You can do this by first solving for mg/hr using the dose calculated for the patient. Dose Conversion Conversion = Wanted Quantity min573mcg x mcgmg10001 x hr1min60 = hrmg = 34 hrmg Using the dose for the patient based on their weight, they should receive 34 mg/hr. To finish back solving, solve for mg/hr using the calculated infusion rate and the DOH. DOH Infusion Rate = Wanted Quantity mLmg250400 x hrmL21 = hrmg = 34 hrmg Using the DOH and the infusion, the patient should receive 34 mg/hr. Since both answers are equal to each other, your calculation is correct.

8 8 Example 6 A patient weighing 98 kg is to receive an infusion of dobutamine at 5mcg/kg/min. Available is 500mg in 250mL of solution. What is the dosage in mcg/min and the infusion rate in mL/hr? First, identify the doctor s order. Doctor s order = min5kgmcg The doctor s order is given as 5mcg/kg/min. This can be written as min5kgmcg. Second, identify the dose on hand (DOH). Dose on hand = mLmg250500 Supplied is 500mg in 250mL of solution. This can be written as mLmg250500. Third, identify the patient s weight. Patient s weight = 198kg The patient s weight given is 98kg. This can be written as 198kg. Now let s first solve for mcg/min using dimensional analysis. Doctor s order Patient s weight Wanted Quantity min5kgmcg x 198kg = min490mcg The dose for this patient would be 490mcg/min. Remember to set up your problem so that the proper units cancel.

9 9 Now that you know the dose for the patient, calculate the infusion rate in mL/hr using dimensional analysis. Patient s dose Conversion DOH Conversion Wanted Quantity min490mcg x mcgmg10001 x mgmL500250 x hr1min60 = hrmL = 15 hrmL The infusion rate would be 15 mL/hr. Remember to set up your problem so that the proper units cancel. To check your answer, back solve. You can do this by first solving for mg/hr using the dose calculated for the patient. Patient s Dose Conversion Conversion = Wanted Quantity min490mcg x mcgmg10001 x hr1min60 = hrmg = 29 hrmg Using the dose for the patient based on their weight, they should receive 29 mg/hr. To finish back solving, solve for mg/hr using the calculated infusion rate and the DOH. DOH Infusion Rate = Wanted Quantity mLmg250500 x hrmL15 = 30 hrmg Using the DOH and the infusion, the patient should receive 30 mg/hr.

10 Since both answers are equal to each other, your calculation is correct. 10 Example 7 A dose of 6mcg/kg/min is ordered to infuse IV to sustain the blood pressure of an adult weighing 75 kg. The supplied solution contains 500mg in 250mL of D5W. Calculate the dose in mcg/min and the infusion rate in mL/hr. First, identify the doctor s order. Doctor s order = min6kgmcg The doctor s order is given as 6mcg/kg/min. This can be written as min6kgmcg. Second, identify the dose on hand (DOH). Dose on hand = mLmg250500 The supplied solution contains 500mg in 250mL of D5W. This can be written as mLmg250500. Third, identify the patient s weight. Patient s weight = 175kg The patient s weight given is 75 kg. This can be written as 175kg. Now let s first solve for mcg/min using dimensional analysis. Doctor s order Patient s weight Wanted Quantity min6kgmcg x 175kg = 450 minmcg The dose for this patient would be 450 mcg/min.