Skip to Main Content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.

Clinical Calculations: Module 9: Pediatric Medications

Pediatric Medications

Module 9 - Calculating Doses of Pediatric Medications

 

What’s in this module?

You will be presented with a pediatric client who is very ill with a disease that can be dangerous to children or adolescents.  Most of the clients will be prescribed more than one medication and some will also have IV fluids.  You will need to determine the correct doses and times for each prescription for the client.  Use your judgment and problem-solving skills to put it all together for each client.

With children and adolescents, the age and weight of the client are essential items to know.  Assessment of the client’s developmental age is also important because the developmental age will determine your approach to the client, the client’s level of understanding, and the client’s degree of fear of medical procedures and medications.  You will learn more about developmental age in other courses in your nursing curriculum.

Pediatric clients are susceptible to illnesses not often seen in adults.  Illnesses that can be minor in adults can be fatal in children due to their smaller body size, lack of immunity or immunizations, and tendency toward dehydration.  Pediatric clients can deteriorate very quickly and must be observed carefully.

What diseases are dangerous to children?  Information from the CDC (Centers for Disease Control and Prevention) in Atlanta indicates that continuing problems for children include tetanus, influenza, hepatitis B, hepatitis A, rubella, influenza type B, measles, pertussis, pneumococcal disease, rotavirus, mumps, chickenpox, and diphtheria.  Polio is still a threat in other countries, but is not now a concern in the U.S. (https://www.cdc.gov/vaccines/parents/diseases/child/14-diseases.html)

Diseases dangerous to children and adolescents differ by age group.  Parents and healthcare providers can be referred to the CDC website that breaks down illnesses by age group. (https://www.cdc.gov/parents/index.html)

 

Summary of problem types in this module

All the problem types you have previously encountered will be reviewed in this module, with special attention given to considerations applicable to pediatric clients.  You should be especially aware of your client’s age and weight.

 

Equivalents to know

You should know all your equivalents by now.

 

Rounding rules to know

You should know all your rounding rules by now.

 

Starting factors and answer units

You should know all your SF and AU by now.  Please refer to previous modules as needed for information about the problem types you will see in this module.

 

Administering Pediatric Medications

Many medication orders for pediatric clients will be weight-based.  Always check the safe dose range for medications if one exists.  Other medications will have doses by age range.  You will need to check the client’s age against the drug manufacturer’s doses listed for the client’s age.

The maximum volume of IM medications should be limited according to the client’s age.  Here are some guidelines:

            Newborn – 0.5 mL

            Infant to 5 years old – 1 mL

            2 mL – 6 to 12 years old

            2-3 mL – adolescent

Adjustments will be made if the client is smaller or larger than the typical range for the client’s age.  Needle sizes will also be smaller, ranging from 5/8” for a newborn to 1 1/2” for an adolescent as the chart below illustrates.

A chart depicting the injection site and needle size for newborns, infants, toddlers, children 3-10, children 11 and older, and adults.

www.immunize.org/catg.d/p2020.pdf       Retrieved 7/16/19

 

IV fluids must be restricted and carefully monitored to avoid overloading the client.  Here is a standard protocol for calculating maintenance IV fluid amounts for pediatric clients.  Note that 2400 mL in 24 hours is the maximum for larger children.  Smaller children receive much smaller amounts. (Reminder:  cc = mL)

A chart indicating the maintenance IV fluid requirements by weight.

https://i.pinimg.com/originals/d1/6f/d1/d16fd1af010b4110584497276b018890.jpg       Retrieved 7/16/19

 

IV fluids typically used in pediatrics include:

A chart illustrating typical pediatric IV fluids, alternate names, and uses.

https://www.rch.org.au/clinicalguide/guideline_index/Intravenous_fluids/       Retrieved 7/16/19

 

IV fluids are frequently administered by micropump, especially for younger children.  A micropump has the capability of delivering IV fluids to the tenths of milliliters as opposed to whole numbers. Be careful to note if a micropump is specified.

 

Image of a burettrol used to deliver small amounts of IV fluid.

3.imimg.com/data3/OY/IY/MY-3729413/burette-set-500x500.jpg        Retrieved 7/16/19

 

For very small amounts of IV fluid, a burette set can be used.  The fluid to be infused is transferred into the chamber of the burette.  An IV bag may be connected to the top of the burette but is optional.  Burettes are used for children for better control of the fluids to be infused.  Filling the burette with only the fluid to be infused in one hour will prevent fluid overload.

The illustration below shows a burette connected to a bag of normal saline.  The small connecting tube allows the nurse to refill the burette as needed without contaminating the sterility of the fluid or the burette.

 

Image of a bag of normal saline connected to a burette and hanging from an IV pole.

https://www.apsf.org/wp-content/uploads/newsletters/2018/3302/figure-1-burette-perpendicular.jpg     Retrieved 7/17/19

 

For the cases below and in the practice problems you will need to use the information about injections and IV fluids from this module.  You will also need to use the information presented about medications and the disease conditions presented in the cases.

Case Example:  Baby A

Image of a child with measles

https://assets.babycenter.com/ims/2013/04/measles_4x3.jpg  Retrieved 7/17/19

Baby A is a six month old child who weighs 7.6 kg.  The client has been admitted to your hospital due to a fever not controlled at home, pneumonia, and dehydration.  These symptoms are complications of measles.  Baby A is clearly uncomfortable and cries frequently.  The baby is on bed rest and oxygen at 1 L/min via pediatric nasal cannula.

 

The healthcare provider has written the following prescriptions:

  1. NS with glucose IV continuous infusion according to hospital protocol for maintenance requirements by weight. Use a micropump with a burette. (Look above for the protocol.) 

Find the ml/hr to set on the micropump you will be using.

 

  1. Acetaminophen 10 mg/kg PO every 4 hours as needed for temperature above 99 degrees Fahrenheit.  Call the healthcare provider if the temperature reaches 100 degrees Fahrenheit.  You have on hand acetaminophen liquid 160 mg/5ml.  Baby A’s current temperature is 38 degrees Celsius.

Does Baby A need acetaminophen for a fever? Do you need to call the healthcare provider? How many ml of acetaminophen liquid will you give Baby A when the medication is needed?

 

  1. Ceftriaxone 75 mg/kg/day IV in two divided doses given in 150 ml NS over three hours.   You have on hand vials of ceftriaxone each containing 250 mg per 10 ml.

How many ml of ceftriaxone will you inject into the 125 ml of NS per dose? What is the flow rate you will use on your micropump to give the medication?

 

  1. Vitamin A 100,000 units po one time today.  You have on hand vitamin A capsules 25,000 units.

How many capsules of vitamin A will you give?

***This case is an example, but try to find the solutions on your own before you look at the answers below.  Refer to previous modules as needed.***

 

Case Example: Baby A - Solutions to Case Questions

  1. IV NS with glucose

SF = 7.6 kg

AU = ml

Equivalents needed:

100 ml = 1 kg (ml = cc)

Equation:

The equation is 7.6 kilograms over 1 times 100 milliliters over 1 kilogram. After cancelling like units, the remaining unit is milliliters. The equation works out to 760 milliliters for the 24 hour period. Divide 760 by 24 to determine the number of milliliters needed per hour. Since the IV pump is a micropump, take the math out 2 places past the decimal point and round to one place past the decimal point. The final answer is 31.7 milliliters per hour.

 

  1. Acetaminophen

SF = 7.6 kg

AU = ml

Equivalents needed:

10 mg = 1 kg

5 ml = 160 mg

Equation:

The equation is 7.6 kilograms over 1 times 10 milligrams over 1 kilogram times 5 milliliters over 160 milligrams. After like units are cancelled, the remaining unit is milliliters. When the equation is solved, the answer is 2.37 milliliters which rounds to 2.4 milliliters per dose.

 

Temperature conversion

The equation is open parenthesis 38 degrees Centigrade times 1.8 close parenthesis plus 32. When solved, the temp in Fahrenheit is 100.4 degrees

Give the acetaminophen and call the healthcare provider.

 

  1. Ceftriaxone

SF = 7.6 kg

AU = ml

Equivalents needed:

75 mg = 1 kg

10 ml = 250 mg

Equation:

The equation is 7.6 kilograms over 1 times 75 milligrams over 1 kilogram times 10 milliliters over 250 milligrams. After like units are cancelled, the remaining unit is milliliters. The final answer is 22.8 milliliter per day.

22.8 ml divided by 2 doses = 11.4 ml ceftriaxone per dose to inject into IV fluid

150 ml IV fluid over 3 hours = 50 ml/hr

 

  1. Vitamin A            

SF = 100,000 units

AU = capsules

Equivalents needed:

1 capsule = 25,000 units

Equation:

The equation is 100 thousand units over 1 times 1 capsule over 25 thousand units. Cancel units. That leaves capsule which is the answer unit. Solve the equation to get 4 capsules.

 

Practice Problems

Module 9 Practice Problems

Case:  Teen B 

Photo of a teenager smiling for the camera.

https://www.liveaction.org/news/wp-content/uploads/2016/11/rihanna-2.jpg    Retrieved 7/21/19

Teen B is 14 years old and weighs 120 lb.  The client is at home in a rural location and you are serving as a visiting nurse.  The client has problems with a bacterial infection of a wound.  You already have prescriptions to dress the wound and apply a topical antibiotic.   The healthcare provider has prescribed additional measures to care for this client:

  1. Continuous IV infusion of LR 1000 ml over 12 hours. No IV pump is available, but you have an IV pole.  The IV set you have on hand has a drop factor of 20 gtts/ml.

Calculate the flow rate in gtts/min for your primary IV infusion.

 

  1. Clindamycin 25 mg/kg/day IV divided every 8 hours.  Give each dose in 250 ml D5W over 3 hours.  The secondary IV set you have on hand has a drop factor of 15 gtts/mL.  See the vial illustrated below for the dosage strength of clindamycin.

Find the amount of clindamycin to give per day and per dose.  Then calculate the flow rate in gtt/min for your secondary IV infusion. 

 

Image of a IV bottle of clindamycin in D5W and the box it came in. The label indicates that there are 50 milliliters in the bottle and that the concentration of the solution is 300 milligrams per 50 milliliters.

https://healthy.kaiserpermanente.org/static/drugency/images/AKN01200.JPG Retrieved 7/20/19

 

  1. Acetaminophen 650 mg po every 4 hours as needed for pain.  Maximum 1 g every 4 hours and 4 g/day from all sources.  You have on hand tablets containing 500 mg and tablets containing 325 mg.  The client is complaining of pain and needs a dose now.

How many tablets of each strength will you give the client per dose?

 

  1. You leave the client to make another home visit then return to Teen B after 3 hours have elapsed.  The client’s IV fluid order has changed to continuous LR 1000 mL over 8 hours. 

What is your new flow rate for the primary IV in gtt/min?

 

Case:  Child C 

Close-up image of a toddler coughing

cdn.mamamia.com.au/wp/wp-content/uploads/2016/04/12050817/whooping_cough_facebook.jpg      Retrieved 7/16/19

Child C has been admitted to the hospital with pertussis (whooping cough).  The client is 3 years old and weighs 33 pounds.  Child C has been coughing so violently that nausea, vomiting, and seizures have been observed by the parents.  The client is on oxygen at 1 L/min via pediatric nasal cannula and has IV access.

You have further orders for this client:

  1. Chlorpromazine 0.55 mg/kg IM every 6 hours as needed for nausea/vomiting.  Give the first dose now.  Maximum 40 mg/day IM. 

You have on hand chlorpromazine 25 mg/ml.

How many ml will you give the client?

 

  1. Lorazepam 2 mg IV push after next seizure. 

Information about lorazepam:Dose for 3 year old child is 0.05 – 0.1 mg/kg IV X1.Push over two minutes. May repeat 0.05 mg/kg X1 after 10-15 minutes.

Calculate the safe dose range for this client (upper and lower limits).Is the healthcare provider’s order safe?

 

  1. Revised prescription for lorazepam: 

Change lorazepam to 0.075 mg/kg IV X1.  Push over two minutes.   May repeat 0.05 mg/kg X1 after 10-15 minutes for seizure activity.

How many ml will you give the client for the first dose?For the second dose?

 

Image of a vial of Lorazepam. The vial contains 1 milliliter of medication and the label indicates that the concentration of the medication is 4 milligrams per milliliter.

https://www.pfizerinjectables.ca/sites/default/files/styles/product_large/public/products/06779001-lorazepam-b-vial-front2_0.jpg?itok=zOI-gWqu

Retrieved 7/20/19

 

  1. Acetaminophen 120 mg PR (per rectum) every 6 hours as needed for pain or fever above 99 degrees Fahrenheit.  Maximum 4 doses in 24 hours.  Do not exceed 75 mg/kg/day. 

You have on hand the 120 mg suppositories.The client’s current temperature is 38 degrees Celsius.

What is the maximum dose per day based on the child’s weight?Do you need to give the first dose now?

 

  1. Azithromycin liquid 10 mg/kg orally daily (max 500 mg) on the first day then 5 mg/kg orally daily for four days (max 250 mg per day).  See the next page for the package label.

Are the prescribed doses under the maximum mg per dose?  How many ml will you give the client on day one?  How many ml will you give the client on days 2-5?

 

Image of a bottle of azithromycin oral suspension. The label indicates the concentration of the solution is 100 milligrams per 5 milliliters.

ep.yimg.com/ay/yhst-135855760451349/azithromycin-suspension-100mg-cherry-16.jpg     Retrieved 7/20/19

 

Case:  Teen D

Image of teenager lying in a hospital bed wearing a facemask for oxygen administration. There is also an IV pump at the bedside with IV fluids infusing. 

images5.fanpop.com/image/photos/25200000/1x12-Code-Breaker-teen-wolf-25286361-1280-720.jpg     Retrieved 7/16/19

Teen D is in isolation at a hospital due to active tuberculosis.   The client is 13 years old and weighs 115 lb.  Oxygen therapy and IV access have already been established.  Continuous IV therapy with LR at 125 ml/hr has been started.

Healthcare providers at the hospital are using CDC guidelines for treatment of TB.   The protocol appears below.

Image of 4 TB treatment regimens ranging from greater effectiveness (Regiman 1) to lesser efffectiveness (Regimen 4). The regimens describe the interval and duration of treatment.

https://www.cdc.gov/tb/topic/treatment/tbdisease.htm       Retrieved 7/22/19

The healthcare providers have decided to use Regimen 1 in the intensive phase to begin treatment.  Since the client is hospitalized, the 7 days/week regimen will be used for the 8 weeks long intensive phase (56 doses).  After discharge, the client will be on the 18 weeks of the continuation phase of medications.

The client’s prescriptions are below.

 

  1. Isoniazid 470 mg IM daily X 40 days. 

Your drug information gives the following limits:

Isoniazid 10-15 mg/kg IM daily for 6-18 months.

Calculate the upper and lower limits for prescription of this medication. Is the prescription correct? Also refer back to the CDC protocol, regimen 1 intensive phase for 7 days/week.

 

  1. Rifampin 15 mg/kg/day IV in 100 ml of D5W.  Infuse over 30 minutes.  Continue for a total of 56 days.

The medication comes in powder form and must be reconstituted.

Image of the label from a vial of rifampin in powder form. Instructions indicate to reconstitute with 10 milliliters of sterile diluent. When dissolved, withdraw 10 milliliters which is equivalent to 600 milligrams of rifampin (60 milligrams per milliliter).

https://www.drugs.com/pro/images/cb59a48c-f66b-4ea0-809c-de0e4be2f8c2/rifampin-for-injection-usp-2.jpg   Retrieved 7/22/19

           

How much diluent will you use?  What is the medication strength after reconstitution?  How many ml of reconstituted medication will you inject into the IV fluid per dose?  What rate will you set on the micropump for the infusion?

 

  1. Ethambutol 1200 mg orally daily for 56 days.

You have on hand 400 mg tablets.

Drug information:

Ethambutol 800 mg daily for client 5 y/o and older 40-55 kg.

Ethambutol 1200 mg daily for client 5 y/o and older 56-75 kg.

Ethambutol 1600 mg daily for client 5 y/o and older 76-90 kg.

Is the prescription correct? What daily dose should the client receive? How many tablets will you give?

 

  1. Pyrazinamide 1000 mg orally daily for 56 days.

You have on hand 500 mg tablets.

Drug information:

Pyrazinamide 1000 mg daily for client 2 y/o and older 40-55 kg.

Pyrazinamide 1500 mg daily for client 2 y/o and older 56-75 kg.

Pyrazinamide 2000 mg daily for client 2 y/o and older 76-90 kg.

Is the prescription correct? What daily dose should the client receive? How many tablets will you give?

 

  1. You have called the healthcare provider and have a revised prescription:

Change isoniazid to 12 mg/kg IM daily X 56 days.

You have on hand isoniazid 100 mg/ml.

How many ml will you give per dose?

 

  1. You have called the healthcare provider and have a revised prescription:

Change ethambutol to 800 mg orally daily for 56 days.

How many tablets will you give per dose?

                                   

Case:  Child E 

Image of a child in a hospital bed with a female nurse on each side of the bed interacting with the child.

https://172dl91lpvim34sra43ilr17-wpengine.netdna-ssl.com/wp-content/uploads/2015/10/5631279558_1e4d3be3cb_b-1024x525.jpg  Retrieved 7/22/19

Child E was admitted to a hospital with appendicitis and now is having an  appendectomy.  Child E is 10 years old and weighs 65 pounds.  IV access has been established.

 

The client has the following prescriptions:

  1. Ondansetron 0.1 mg/kg IVP X1 over 15 minutes.  Give shortly after surgery.

How many ml will you give? How many ml per minute?

Image of a vial of ondansetron injection. The label indicates that the concentration of the medication is 2 milligrams per milliliter.

drugline.org/img/drug/ondansetron-injection-17054_1.jpg    Retrieved 7/23/19

 

  1. Piperacillin/tazobactram (Zosyn) 300 mg/kg/day IV divided every 8 hours X 10 days.  Give in 125 ml NS over 30 min.  Stop primary infusion while administering.  Flush IV site with 100 ml NS before and after administration.

How much diluent will you use to reconstitute this medication?How many ml will you give the client per dose?How many ml/hr will you set on the micropump?

Image of a vial of piperacillin and tazobactam for injection. The medication is in powder form.

sterimaxinc.com/wp-content/uploads/2014/12/piperaillin-tazobactam-3-375g-300x300.png   Retrieved 7/23/19

 

Drug information

Image of reconstitution directions. Reconstitute with 5 milliliters of diluent per 1 gram of piperacillin and then further dilute in a bag of IV fluid. There is a list of IV with which the medication is compatible. Directions indicate that the IV fluid with medication should be administered over 30 minutes.

https://reference.medscape.com/drug/zosyn-piperacillin-tazobactam-342485#11   Retrieved 7/23/19

 

  1. Hydromorphone 17 mcg/kg IV every six hours in 100 ml NS.  Give over 20 minutes.

Your drug information states that the allowable dose is 15-20 mcg/kg IV every 4-6 hours.What are the upper and lower limits per dose?

How many ml of hydromorphone will you give the client for each dose? How many ml per minute will you set on the micropump?

 

Image of a vial of hydromorphone and the box in which it came. The label indicates that the concentration of the medication for injection is 2 milligrams per milliliter.

img.medscapestatic.com/pi/features/drugdirectory/octupdate/BAX-121-.jpg     Retrieved 7/23/19

 

  1. Continuous infusion of LR 1000 ml over 10 hours

What flow rate will you set of the IV pump?

 

  1. Soft diet, oxygen therapy at 1 L/min, activity as tolerated, incentive spirometer after surgery.

 

Answers to Practice Problems

Answers to Module 9 Practice Problems

Case:  Teen B  - Answers to Case Questions

Teen B is 14 years old and weighs 120 lb.  The client is at home in a rural location and you are serving as a visiting nurse.  The client has problems with a bacterial infection of a wound.  You already have prescriptions to dress the wound and apply a topical antibiotic.   The healthcare provider has prescribed additional measures to care for this client:

  1. Continuous IV infusion of LR 1000 mL over 12 hours. No IV pump is available, but you have an IV pole.  The IV set you have on hand has a drop factor of 20 gtts/mL.

Calculate the flow rate in gtts/min for your primary IV infusion.

Continuous IV infusion by gravity

 

SF = 1 min

AU = gtts

Equivalents:

            1000 mL = 12 hours

            20 gtts = 1 mL

            60 min = 1 hour

Equation:

The equation is 1 minute over 1 times 1 hour over 60 minutes times 1000 milliliters over 12 hours times 20 drops over 1 milliliter. Cancel like units. That leaves gtts, which is your answer unit. Solve the equation to get 27.7 which rounds to 28 drops per minute.

 

  1. Clindamycin 25 mg/kg/day IV divided every 8 hours.  Give each dose in 250 mL D5W over 3 hours.  The secondary IV set you have on hand has a drop factor of 15 gtts/mL.  See the vial for the dosage strength of clindamycin.

Find the amount of clindamycin to give per day and per dose.  Then calculate the flow rate in gtt/min for your secondary IV infusion. 

 

Clindamycin IV injection

SF = 120 lbs

AU = mL

Equivalents:

1 kg = 2.2 lbs

25 mg = 1 kg

50 mL = 300 mg

Equation:

The equation is 120 pounds over 1 times 1 kilogram over 2.2 pounds times 25 milligrams over 1 kilogram times 50 milliliters over 300 milligrams. Cancel like units. That leaves milliliters which is your answer unit. Solve the equation to get 227.27 which rounds to 227.3 milliliters per day.

Since every 8 hours means three times a day, to determine how many mL to give each dose divide the total by 3 doses.

The equation is 227.272 milliliters over 3 doses. Solve the equation to get 75.75 which rounds to 75.8 milliliters per dose.

Note: When determining the amount of medication per dose, do not round until after you calculate the amount for the individual dose.

 

IV flow rate

SF = 1 min

AU = gtts

Equivalents:

1 hr = 60 min

250 ml = 3 hrs

15 gtt = 1 mL

Equation:

The equation is 1 minute over 1 times 1 hour over 60 minutes times 250 milliliters over 3 hours times 15 drops over 1 milliliter. Cancel like units. That leaves drops which is your answer unit. Solve the equation to get 20.8 which rounds to 21 drops per minute.

 

  1. Acetaminophen 650 mg PO every 4 hours as needed for pain.  Maximum 1 g every 4 hours and 4 g/day from all sources.  You have on hand tablets containing 500 mg and tablets containing 325 mg.  The client is complaining of pain and needs a dose now.

How many tablets of each strength will you give the client per dose?

 

Acetaminophen tablets

You need a total dose of 650 milligrams. 650 minus one 500 milligram tablet leaves 150 milligrams to be given with the 325 milligram tablets.

SF = 150 mg

AU = tablets

Equivalents:

1 tab = 325 mg 

Equation:

The equation is 150 milligrams over 1 times 1 tab over 325 milligrams. Cancel like units. That leaves you with tab. Solve the equation to get 0.46 tab.

According to the rounding rule for tablets, an answer less than a half tablet exactly rounds down to the previous whole number. In this case, that would be zero tablets. That does not help you get to the needed 650 mg dose. The closest amount that can be given with the tablets on hand would be 0.5 tablet. However, a whole 650 mg tablet and a half of a 325 mg tablet would be 662.5 mg.

The equation is 0.5 times 325 milligrams which equals 162.5 mg plus 500 milligrams which equals a total of 662.5 milligrams.

You would need to call the healthcare provider and ask for an order for 662.5 mg until 650 mg tablets are available.  

 

  1. You leave the client to make another home visit then return to Teen B after 3 hours have elapsed.  The client’s IV fluid order has changed to continuous LR 1000 mL over 8 hours. 

What is your new flow rate for the primary IV in gtt/min?

 

Adjustment to IV

SF = 1 min

AU = gtts

Equivalents:

1000 mL = 8 hrs

20 gtts = 1 mL

Equation:

The equation is 1 minute over 1 times 1 hour over 60 minutes times 1000 milliliters over 8 hours times 20 drops over 1 milliliter. Cancel like units. That leaves you with drops, which is your answer unit. Solve the equation to get 41.6 which rounds to 42 drops per minute.

 

Case:  Child C  - Answers to Case Questions

Child C has been admitted to the hospital with pertussis (whooping cough).  The client is 3 years old and weighs 33 pounds.  Child C has been coughing so violently that nausea, vomiting, and seizures have been observed by the parents.  The client is on oxygen at 1 L/min via pediatric nasal cannula and has IV access.

You have further orders for this client:

  1. Chlorpromazine 0.55 mg/kg IM every 6 hours as needed for nausea/vomiting.  Give the first dose now.  Maximum 40 mg/day IM. 

You have on hand chlorpromazine 25 mg/mL.

How many mL will you give the client?

 

SF = 33 lbs

AU = mL

Equivalents:

1 kg = 2.2 lb

0.55 mg = 1 kg

1 mL = 25 mg

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 0.55 milligrams over 1 kilogram times 1 milliliter over 25 milligrams. Cancel like units. That leaves you with milliliters which is your answer unit. Solve the equation to get 0.33 milliliters.

 

  1. Lorazepam 2 mg IV push after next seizure. 

Information about lorazepam: Dose for 3 year old child is 0.05 – 0.1 mg/kg IV X1. Push over two minutes. May repeat 0.05 mg/kg X1 after 10-15 minutes.

Calculate the safe dose range for this client (upper and lower limits). Is the healthcare provider’s order safe?

Upper limit

SF = 33 lbs

AU = mg

Equivalents:

0.1 mg = 1 kg

1 kg = 2.2 lbs

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 0.1 milligram over 1 kilogram. Cancel like units. That leaves milligram which is your answer unit. Solve the equation to get 1.5 milligrams.

Lower limit

SF = 33 lbs

AU = mg

Equivalents:

0.05 mg = 1 kg

1 kg = 2.2 lbs

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 0.05 milligrams over 1 kilogram. Cancel like units. That leaves milligram which is your answer unit. Solve the equation to get 0.75 milligrams.

Do not give the medication.  The 2 mg dose prescribed is above the upper limit for this client.  Call the healthcare provider for a new prescription.

 

  1. Revised prescription for lorazepam: 

Change lorazepam to 0.075 mg/kg IV X1.  Push over two minutes.   May repeat 0.05 mg/kg X1 after 10-15 minutes for seizure activity.

How many ml will you give the client for the first dose? For the second dose?

 

First Dose

SF = 33 lb

AU = ml

Equivalents:

0.075 mg = 1 kg

1 mL = 4 mg

1 kg = 2.2 lbs

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 0.075 milligram over 1 kilogram times 1 milliliter over 4 milligrams. Cancel like units. That leaves milliliter which is your answer unit. Solve the equation to get 0.281 which rounds to 0.28 milliliters.

 

Remaining Doses

SF = 33 lb

AU = ml

Equivalents:

0.05 mg = 1 kg

1 ml = 4 mg

1 kg = 2.2 lb

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 0.05 milligrams over 1 kilogam times 1 milliliter over 4 milligrams. Cancel like units. That leaves milliliter which is your answer unit. Solve the equation to get an answer of 0.187 which rounds to 0.19 mL.

 

  1. Acetaminophen 120 mg PR (per rectum) every 6 hours as needed for pain or fever above 99 degrees Fahrenheit.  Maximum 4 doses in 24 hours.  Do not exceed 75 mg/kg/day. 

You have on hand the 120 mg suppositories.  The client’s current temperature is 38 degrees Celsius.

What is the maximum dose per day based on the child’s weight?  Do you need to give the first dose now?

 

SF = 33 lbs

AU = mg

Equivalents:

75 mg = 1 kg

1 kg = 2.2 lbs

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 75 milligrams over 1 kilogram. Cancel like units. That leaves milligram which is your answer unit. Solve the equation to get 1,125 mg for the maximum dose.

 

Temperature:

The equation is 38 degrees Centigrade times 1.8, then add 32 to get an answer of 100.4 degrees Fahrenheit.

Give the suppository now.

 

  1. Azithromycin liquid 10 mg/kg orally daily (max 500 mg) on the first day then 5 mg/kg orally daily for four days (max 250 mg per day).  See the package label.

Are the prescribed doses under the maximum mg per dose?  How many mL will you give the client on day one?  How many mL will you give the client on days 2-5?

 

Day 1

SF = 33 lbs

AU = mg

Equivalents:

10 mg = 1 kg

1 kg = 2.2 lb

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 10 milligram over 1 kilogram. Cancel like units. That leaves milligram, which is the answer unit. Solve the equation to get 150 milligrams.

 

Days 2-5

SF = 33 lbs

AU = mg

Equivalents:

5 mg = 1 kg

1 kg = 2.2 lbs

Equation:

The equation is 33 pounds over 1 times 1 kilogram over 2.2 pounds times 5 milligrams over 1 kilogram. Cancel like units. That leaves milligrams, which is your answer unit. Solve the equation to get 75 milligrams.

Both prescriptions are below the maximum dose for the client.

 

Medication strength is 100 mg per 5 mL.

Dose for day 1

SF = 150 mg

AU = mL

Equivalents:

100 mg = 5 mL

Equation:

The equation is 150 milligrams over 1 times 5 milliliters over 100 milligrams. Cancel milligrams. That leaves milliliters which is your answer unit. Solve the equation to get 7.5 milliliters.

 

Dose for days 2-5

SF = 75 mg

AU = mL

Equivalents:

100 mg = 5 mL

Equation:

The equation is 75 milligrams over 1 times 5 milliliters over 100 milligrams. Cancel milligrams. That leaves milliliters which is the answer unit. Solve the equation to get 3.75 which rounds to 3.8 milliliters.

 

Case:  Teen D - Answers to Case Questions

Teen D is in isolation at a hospital due to active tuberculosis.  The client is 13 years old and weighs 115 lbs.  Oxygen therapy and IV access have already been established.  Continuous IV therapy with LR at 125 mL/hr has been started.

Healthcare providers at the hospital are using CDC guidelines for treatment of TB.  The healthcare providers have decided to use Regimen 1 in the intensive phase to begin treatment.  Since the client is hospitalized, the 7 days/week regimen will be used for the 8 weeks long intensive phase (56 doses).  After discharge, the client will be on the 18 weeks of the continuation phase of medications.

  1. Isoniazid 470 mg IM daily X 40 days. 

Your drug information gives the following limits:

Isoniazid 10-15 mg/ kg IM daily for 6-18 months.

Calculate the upper and lower limits for prescription of this medication.  Is the prescription correct?  Also refer back to the CDC protocol, regimen 1 intensive phase for 7 days/week.

Upper limit

SF = 115 lbs

AU = mg

Equivalents:

15 mg = 1 kg

1 kg = 2.2 lb

Equation:

The equation is 115 pounds over 1 times 1 kilogram over 2.2 pounds times 15 milligrams over 1 kilogram. Cancel like units. Thats leaves milligram which is the answer unit. Solve the equation to get 784.09 which rounds to 784.1 milligrams.

Lower limit

SF = 115 lbs

AU = mg

Equivalents:

10 mg = 1 kg

1 kg = 2.2 lb

Equation:

The equation is 115 pounds over 1 times 1 kilogram over 2.2 pounds times 10 milligrams over 1 kilogram. Cancel like units. That leaves milligram which is the answer unit. Solve the equation to get 522.72 which rounds to 522.7 milligrams.

Don’t give the medication.  Call the healthcare provider.  The prescribed dose is below the lower limit and may not be effective.  Also, the CDC protocol for 7 days per week calls for 56 doses in the intensive phase for the regimen being used.

 

  1. Rifampin 15 mg/kg/day IV in 100 ml of D5W.  Infuse over 30 minutes.  Continue for a total of 56 days.

The medication comes in powder form and must be reconstituted.        

How much diluent will you use?  What is the medication strength after reconstitution?  How many mL of reconstituted medication will you inject into the IV fluid per dose?  What rate will you set on the micropump for the infusion?

 

Info from the rifampin label:

Use 10 ml of sterile diluent.

After reconstitution 60 mg = 1 ml.

 

Amount of medication to add to the IV fluid:

SF = 115 lb

AU = ml

Equivalents:

15 mg = 1 kg

1 ml = 60 mg

1 kg = 2.2 lb

Equation:

The equation is 115 pounds over 1 times 1 kilogram over 2.2. pounds times 15 milligrams over 1 kilogram times 1 milliliter over 60 milligrams. Cancel like units. Solve the equation to get 13.06 which rounds to 13.1 milliliters.

The 13.1 mL of reconstituted medication will be added to 100 ml D5W.

The 100 ml of D5W is to be given over 30 min.  A flow rate of 200 ml/hr should be set on the pump to give 100 ml in 30 minutes.

SF = 1 hr

AU = mL

Equivalents:

100 mL = 30 mins

1 hr = 60 mins

Equation:

The equation is 1 hour over 1 times 60 minutes over 1 hour times 100 milliliters over 30 minutes. Cancel like units. That leaves milliliters which is your answer unit. Solve the equation to get 200 milliliters per hour.

 

  1. Ethambutol 1200 mg orally daily for 56 days.

You have on hand 400 mg tablets.

Drug information:

Ethambutol 800 mg daily for client 5 y/o and older 40-55 kg.

Ethambutol 1200 mg daily for client 5 y/o and older 56-75 kg.

Ethambutol 1600 mg daily for client 5 y/o and older 76-90 kg.

Is the prescription correct?  What daily dose should the client receive?  How many tablets will you give?

 

SF = 115 lb

AU = kg

Equivalents:

1 kg =2.2 lb

Equation:

The equation is 115 pounds over 1 times 1 kilogram over 2.2 pounds. Cancel pounds. That leaves kilograms which is the answer unit. Solve the equation to get 52.27 which rounds to 52.3 kilograms.

Based on a weight of 52.3 kg, the dose for the client should be 800 mg daily instead of the ordered 1200 mg.  Do not give the medication.  Call the healthcare provider for a new prescription.

 

  1. Pyrazinamide 1000 mg orally daily for 56 days.

You have on hand 500 mg tablets.

Drug information:

Pyrazinamide 1000 mg daily for client 2 y/o and older 40-55 kg.

Pyrazinamide 1500 mg daily for client 2 y/o and older 56-75 kg.

Pyrazinamide 2000 mg daily for client 2 y/o and older 76-90 kg.

Is the prescription correct?  What daily dose should the client receive?  How many tablets will you give?

The prescribed dose is correct for 52.3 kg.

SF = 1000 mg

AU = tabs

Equivalents:

1 tab = 500 mg

Equation:

The equation is 1000 milligrams over 1 times 1 tablet over 500 milligrams. Cancel milligrams. That leaves tablet which is the answer unit. Solve the equation to get 2 tablets.

 

  1. You have called the healthcare provider and have a revised prescription:

Change isoniazid to 12 mg/kg IM daily X 56 days.

You have on hand isoniazid 100 mg/ml.

How many ml will you give per dose?

SF = 52.3 kg

AU = ml

Equivalents:

1 kg = 12 mg

1 ml = 100 mg

Equation:

The equation is 52.3 kilograms over 1 times 12 milligrams over 1 kilogram times 1 milliliter over 100 milligram. Cancel like units. That leaves milliliter which is the answer unit. Solve the equation to get 6.27 which rounds to 6.3 milliliters.

 

  1. You have called the healthcare provider and have a revised prescription:

Change ethambutol to 800 mg orally daily for 56 days.

How many tablets will you give per dose?

SF = 800 mg

AU = tabs

Equivalent:

1 tab = 400 mg

Equation:

The equation is 800 milligrams over 1 times 1 tablet over 400 milligrams. Cancel milligrams. That leaves tablets which is your answer unit. Solve the equation to get 2 tablets.

 

Case:  Child E - Answers to Case Questions

Child E was admitted to a hospital with appendicitis and now is having an appendectomy.  Child E is 10 years old and weighs 65 pounds.  IV access has been established.

The client has the following prescriptions:

  1. Ondansetron 0.1 mg/kg IVP X1 over 15 minutes.  Give shortly after surgery.

How many mL will you give? How many mL per minute?

SF = 65 lb

AU = mL

Equivalents:

0.1 mg = 1 kg

1 mL = 2 mg

1 kg = 2.2 lb

Equation:

The equation is 65 pounds over 1 times 1 kilogram over 2.2 pounds times 0.1 milligrams over 1 kilogram times 1 milliliter over 2 milligrams. Cancel like units. That leaves milliliter which is your answer unit. Solve the equation to get 1.47 which rounds to 1.5 milliliter.

To determine the mL to administer per minute, divide 1.5 mL by 15 to get 0.1 mL/min slow IVP.

 

  1. Piperacillin/tazobactram (Zosyn) 300 mg/kg/day IV divided every 8 hours X 10 days.  Give in 125 mL NS over 30 min.  Stop primary infusion while administering.  Flush IV site with 100 mL NS before and after administration.

How much diluent will you use to reconstitute this medication?  How many mL will you give the client per dose?  How many mL/hr will you set on the micropump?

 

Diluent for the medication:

The drug information indicates to reconstitute with 5 mL diluent per 1 g. The label on the vial indicates that there are 3.375 g of medication in the vial.

SF = 3.375 g

AU = mL

Equivalents:

1 g = 5 mL

Equation:

The equation is 3.375 grams over 1 times 5 milliliters over 1 gram. Cancel gram. That leaves milliliters. Solve the equation to get 16.87 which rounds to 16.9 milliliters.

 

Medication per dose:

SF = 65 lbs

AU = mL

Equivalents:

300 mg = 1 kg

16.9 ml = 3.375 g

1 kg = 2.2 lb

1g = 1000 mg

3 doses

Equation:

The equation is 65 pounds over 1 times 1 kilogram over 2.2 pounds times 300 milligram over 1 kilogram times 1 gram over 1000 milligrams times 16.9 milliliters over 3.375 gram. Cancel like units. That leaves milliliters which is the answer unit. Do not round at this point. Divide by the 3 doses to get 14.79 which then rounds to 14.8 milliliters per dose.

Add the 14.8 mL to 125 mL NS to be given over 30 minutes.  Determine the flow rate to set on the pump.

SF = 1hr

AU = mL

Equivalents:

125 mL = 30 mins

1 hr = 60 mins

Equation:

The equation is 1 hour over 1 times 60 minutes over 1 hour times 125 milliliters over 30 minutes. Cancel like units. That leaves milliliters which is your answer unit. Solve the equation to get a flow rate of 250 milliliters per hour.

 

  1. Hydromorphone 17 mcg/kg IV every six hours in 100 ml NS.  Give over 20 minutes.

Your drug information states that the allowable dose is 15-20 mcg/kg IV every 4-6 hours. What are the upper and lower limits per dose?

How many mL of hydromorphone will you give the client for each dose? How many mL per minute will you set on the micropump?

 

Upper limit per dose

SF = 65 lb

AU = mcg

Equivalents:

1 kg = 2.2 lb

20 mcg = 1 kg

Equation:

The equation is 65 pounds over 1 times 1 kilogram over 2.2 pounds times 20 micrograms over 1 kilogram. Cancel like units. That leaves microgram which is your answer unit. Solve the equation to get 590.90 which rounds to 590.9 micrograms.

Lower limit per dose

SF = 65 lb

AU = mcg

Equivalents:

1 kg = 2.2 lb

15 mcg = 1 kg

Equation:

The equation is 65 pounds over 1 times 1 kilogram over 2.2 pounds times 15 micrograms over 1 kilogram. Cancel like units. That leaves micrograms which is your answer unit. Solve the equation to get 443.18 which rounds to 443.2 micrograms.

 

Dose for the client

SF = 65 lb

AU = mL

Equivalents:

17 mcg = 1 kg

1 mL = 2 mg

1 kg = 2.2 lb

1 mg = 1000 mcg

Equation:

The equation is 65 pounds over 1 times 1 kilogram over 2.2 pounds times 17 micrograms over 1 kilogram times 1 milligram over 1000 micrograms times 1 milliliter over 2 milligrams. Cancel like units. That leaves milliliters which is your answer unit. Solve the equation to get 0.251 which rounds to 0.25 milliliters per dose.

 

Add the 0.25 mL to 100 ml NS. Give over 20 minutes. What is the flow rate to set on the IV pump? 

SF = 1 hr

AU = mL

Equivalents:

100 mL = 20 mins

1 hr = 60 mins

Equation:

The equation is 1 hour over 1 times 60 minutes over 1 hour times 100 milliliters over 20 minutes. Cancel like units. That leaves milliliters which is your answer unit. Solve the equation to get a flow rate of 300 milliliters per hour.

 

  1. Continuous infusion of LR 1000 mL over 10 hours

What flow rate will you set on the IV pump?

 

SF = 1 hr

AU = mL

Equivalents:

1000 mL = 10 hours

Equation:

The equation is 1 hour over 1 times 1000 milliliters over 10 hours. Cancel hours. That leaves milliliters which is your answer unit. Solve the equation to get a flow rate of 100 milliliters per hour.

 

  1. Soft diet, oxygen therapy at 1 L/min, activity as tolerated, incentive spirometer after surgery.

©2021 Georgia Highlands College | ask@highlands.libanswers.com