04/15/2023 1

PEDIATRIC HEALTH NURSING UNIT III : PHARMACOLOGICAL CARE ASPECTS WHILE

DEALING WITH PEDIATRIC PATIENTS

MUHAMMAD SULIMANPost RN BSc.N

ROYAL COLLEGE OF NURSING SWAT

IntroductionAdults and children respond to drugs differently. Disparities include the absorption, distribution, metabolism and elimination of the drug by the body as well as differences in formulation, dosage and administration.

Medications that are used commonly in paediatric practice do have well-articulated details such as age/weight dosing, implications for breast-feeding and important information related to drug absorption, distribution, elimination and adverse events. It is imperative that the clinician caring for children utilises this information to maximise the benefits of pharmacological agents.

Cont…It is important to recognise that the nature, duration of effect and intensity of a drug's action are related not only to the intrinsic properties of the drug itself but also to the drug's interaction with the patient to whom it has been administered. Therefore, effective and safe drug therapy in neonates, infants, children and adolescents requires an understanding of the differences in drug action, metabolism and disposition that are determined developmentally.

Nearly all pharmacokinetic parameters change with age and as a result, paediatric drug dosages must be adjusted accordingly. Likewise, issues such as medication administration and formulation have concordance implications in paediatrics.

Cont…• Birth to 1 year of age have greater percentage

of body water

• Age 1 to 12 years metabolize drugs more readily than adults

• Children at risk for overdose, toxic reactions, and death

– Due to immature physiological processes

• E.g., absorption, distribution, metabolism, excretion

Before you make a start

• Familiarize yourself with your local medicines policy and procedures

• Be aware of PNC Code of Conducts, PMDC Standards for Medicines Management

• Understand why your patient has been prescribed this medication, check the care plans as well as dose, possible adverse effects, contraindications and special precautions

• Check prescription charts regularly. Omission is the second most common reason for medication error

• Gather together the prescription chart, keys and second RN to act as checker if required

• Wash your hands

Check prescription chart• Has the correct patient identification. Full name, NHS

number and/or hospital number if required by local policy

• Has a completed and signed confirmation of allergy status on the front of the chart

• Provides a clear legible prescription of medication to be administered. If this appears ambiguous it is safer to request that the prescription chart is rewritten. Prescriptions should include date of prescription, the generic drug name, route, dosage, date and time to be administered and the prescriber’s printed name and signature

• Remember All checks should be completed independently

Preparing the medicine• With the second checker, select the correct medication and

check that it is within the expiry date. Consider formula/spoon/oral syringe preference for children

• Check that the dose prescribed is correct for the age and weight of the patient using a reference source

• Independently calculate the volume of liquid or number of tablets required. Compare answers. Recalculate if you disagree

• Measure the dose required. Both practitioners should witness all stages of the process and confirm the amount prepared. Both nurses should undertaken at bedside checks together

Administering the medicine• Check that the patient’s name, date of birth and NHS number on

the name band correlate with these details on the prescription chart

• If possible, ask the patient/parent to tell you his/her name and date of birth

• Check the allergy section on the prescription chart for contraindications to administration

• Explain purpose of the medication to the patient/ family and gain consent for administration

• The patient/family/non-registered nurse/play specialist may wish to be involved in the administration procedure. Remember This must always be performed under the supervision of an RN who remains accountable for any delegation of this task

Closing the intervention• After administering the medication both nurses should sign the

prescription chart to evidence that the medication has been given

• Offer the patient a drink, particularly if the medicine has an unpleasant taste

• Record reasons for non-administration of the drug on the prescription chart and in the nursing documentation

• Make the patient comfortable. Offer bravery rewards if appropriate. Ask whether there are any further interventions required. Inform the patient and/or family when you will be returning

• Dispose of equipment safely with clean spacers as required. Wash your hands

• Observe patient for adverse effects

Involving the child, young personand family

The admission process for children and young people should assess and record details of the child or young person’s prescribed medication, together with their preferences for when this is usually taken and how all medications are usually given (e.g. tablet, syrup, spoon, syringe). Many children’s hospitals operate parent administration procedures that maintain home routine, facilitate integrated family and health care partnership working and help to protect against medication errors (Crawford 2012). The role of the children’s nurse in this process is to provide support to families but remain mindful of the NMC (2010) requirement to ascertain that medication has been administered as recorded.

Cont…Medications dispensed by hospital pharmacies for

discharge frequently do not include guidance on usage. NICE (2009) estimate that 33–50% of all patients with long-term conditions do not take medication as directed, potentially at a cost of over £100 million per year. As children and young people are reliant upon parental understanding of medicine regimes for their well-being, they are particularly vulnerable. The children’s nurse therefore has a key role in explaining rationale for dose, frequency, specific instructions and adverse effects of medication to children, young people and their parents and carers.

Medicines safetyMedication error was the most frequently reported adverse

incident reported during an NPSA (2009) patient safety review. Ten per cent of errors affected the 0–4 year age group. The most common error was incorrect dose, followed by omitted doses and incorrect frequency. It is widely acknowledged that although these events are preventable, health care providers will never achieve a position of zero medication incidents (Chang and Mark 2011). What is important is that children’s nursing learns from these events and as advocated by the Children and Young People’s Health Outcomes Forum (2012), initiate bundles of interventions to reduce their frequency.

Administering Medications toChildren

• Safe pediatric dosages calculated by:

– Body weight

• Measured in mg per kg, mcg per kg, etc.

– Body surface area (BSA)

• Measured in m2

Calculation formula

Dose = What you want × Amount it is in What you haveFor example: you need to administer 60mg

paracetamol which comes as a 120-mg in 5-mL preparation:

Dose = 60/120 × 5 = ½ × 5 = 5/2 = 2.5mL

Units of measurement

1 gram (g) = 1000 milligram (mg)1 milligram (mg) = 1000 microgram (μg)1 microgram (μg) = 1000 nanogram (ng)1 litre (L) = 1000 millilitres (mL).

Calculating IV fluid ratesRate = volume/timeExample 500mL over 4 hoursRate = 500/4 = 125mL/hour

Principles of drug calculationsThe metric system

To undertake drug calculations it is imperative to understand the units of measurement used in the prescribing and administration of drugs. The units are expressed using the System International within the standard metric system of weights and measures (Blair 2011).

Units Abbreviations Conversions

Kilogram kg 1kg = 1000 g

Gram g 1g = 1000 mg

Milligram mg 1 mg = 1000 microgram

Microgram Do not abbreviate NA

Litre L 1 L = 1000 m L

Millilitre m L NA

Cont…

ProportionsMany calculations that are undertaken on a children’s ward

are based on weight and volume. This is because a dosage weight of drug has been dissolved in a volume of liquid. For example, an elixir that contains the dose strength of 125 mg in 5 mL means that in every 5 mL of liquid will be 125 mg of the drug.

Strength of the medicine 125 mg in 5 mL

If you halve the dose 62.5 mg in 2.5 mL

If you double the dose 250 mg in 10 mL

FractionsA useful resource when undertaking drug calculations is

to learn common fractions expressed as a decimal. This is helpful when calculating dosages from ampoules.

½ = 1.5 ¼ = 0.25 1/5 = 0.2

2/4 = 0.5 2/5 = 0.4

3⁄4 = 0.75 3⁄5 = 0.6

4⁄5 = 0.8

Worked exampleIf you require half of a 1-mL ampule you will require 0.5 mL

Dividing and multiplying by 10, 100 and 1000

Many drug doses and stock strengths are given in multiples of 10. A useful skill is to be able to recognize when a dose is a multiple of 10 or 100 and understand their relationship.

10 mg 10 × 1 mg

100 mg 10 × 10 mg

20 mg 10 × 2 mg

50 mg 10 × 5 mg

1000 mg 10 × 100 mg

Formula methodThis method requires relevant numerical figures to be

inserted into an equation, which once solved provides the necessary volume of liquid or number of tablets that need to be administered

• What you want (prescription) ÷ What you have (stock strength) × What its in (volume) = Volume to be administered

• What you want (prescription) ÷ What you have (stock strength) = Number of tablets to be administered

Worked examples• You need to administer 120 mg paracetamolThe dose strength available is 120 mg paracetamol in 5 mL= 120 ÷ 120 × 5 = 5 mL

Cont…

• You need to administer 25 mg prednisolone

This is available in 5 mg tablets

= 25 ÷ 5 = 5 tablets

Children and Young People’s Nursing at a Glance, First Edition. Edited by Alan Glasper, Jane Coad, and Jim Richardson.

© 2015 John Wiley & Sons, Ltd. Published 2015 by John Wiley & Sons, Ltd. Companion website: www.ataglanceseries.com/nursing/children

Numeracy

It is vital that paediatric nurses have sound numeracy skills to assist them within a range of health care activities. One such activity is drug calculation and administration. Poor numeracy skills may lead to medication errors. While recognizing that medication errors are multifactorial, lack of competence in basic calculation is often reported as a key area of concern for many trusts (Fry and Dacey 2007).

EstimationBeing able to estimate the answer sought is essential in drug

calculations. Many medication errors occur as the practitioner has not thought through what a sensible answer or dose would be. A moment taken to approximate the calculation will prevent serious errors, such as a misplaced decimal point (Hutton 2009).

Using a calculator:

Paediatric nurses should be able to undertake non-complex drug calculations without the use of a calculator. A calculator provides an answer to the equation that is keyed in; if the equation is incorrect it is easy to generate the wrong answer.

Cont…However, it would be acceptable to calculate the dose needed

and then check the answer using a calculator. For more complex drug calculations, it may be necessary to use a calculator, although the correct answer should be estimated to ensure the calculation is correct.

Checking the dose:

Before administering a drug to a child the nurse must be sure that the prescribed dose is correct. While errors may be made by prescribers as well as those who administer the prescription, accountability sits with both. Double checking is recommended for complex drug calculations.

Cont…Checking must involve each nurse independently undertaking

the calculation and then both checking the answer together (NMC 2010b). There are some academics who believe that double checking may increase the risk of error as each become complacent and rely on the other to spot an error. This is why it is imperative that nurses undertake the calculation independently before doing it jointly.

Recommendations for practice:

Medication administration incidents are most frequently due to the wrong dose, delayed or omitted medication or the wrong medication being administered (NPSA 2009; Nursing Times 2012), with the most frequently cited error being calculation error.

Cont…Health care organizations must ensure that they implement

routine and regular assessment of their clinical staff’s numeracy skills. This should form part of their mandatory clinical update and continued professional development. It is hoped that the implementation of such strategies will lead to an increased awareness of the importance of numeracy and thus an improved quality of care of patients and a reduced risk of medication errors (Warburton 2010).

Key points• Understand professional responsibility and accountability.

• Understand units of measurement.

• Possess sound knowledge of calculation formulas.

• Estimate the required volume and/or number of tablets.

• Double check when appropriate.

• Employers should demonstrate yearly assessment of practitioner’s numeracy skills.

PRACTICE TESTSExample 1

A child is prescribed 100mg fluconazole, which is supplied as capsules, each containing 50mg. The nurse must work out how many capsules to give. Two 50mg capsules would provide 100mg of drug – easy! Let’s look at how you got that answer:

The dose prescribed, or what you want, was 100mg.

The dose per available capsule, or what you’ve got, was 50mg.

To get two capsules, you divided 100 by 50.

Dose = what you want / what you’ve got = 100/50 = 2 capsules

Cont…Example 2

A toddler is prescribed flucloxacillin 250mg. This drug is available in syrup form, 125mg in 5ml. How much should you give?

First estimate a sensible dose. If 5ml contains 125mg, then you’ll need more than 5ml for a dose of 250mg. In fact you can probably see that 125 is half of 250 and so a dose of 10ml is required. Would using the formula give this answer?

what you want / what you’ve got = 250 / 125 = 2

The answer is 2. Is this right? Two ‘what's’?

Cont…It can’t be 2mls because we have estimated that it should be

more than 5mls.

Remember that each 125mg dose of what we have, is contained in 5ml and so the answer is two lots of 5ml, in other words, 10ml. So, to get the correct answer, we also need to multiply by the measure that the available drug is in. Let’s add this to the formula to make it work for this type of prescription.

Dose = what you want / what you’ve got x what’s it’s in

Check by substituting the values we have above.

The answer is 10ml, which is what we had already decided.

Practice exercisesUse the formula to work out the volume you would give for

the following:

1. A child is prescribed oral chloral hydrate 250mg. The drug is available as an elixir containing 200mg in 5ml.

2. Prescription is oral phenobarbital (phenobarbitone) 45mg. It is available as 15mg in 5ml.

3. Metronidazole comes as 100mg in 20ml. The child is prescribed 75mg IV.

4. Oral paracetamol 80mg is prescribed. It is available as a syrup with 120mg in 5ml.

5. Baby is to have 25 microgram digoxin IV. It is available as 500 microgram in 2ml.

Dosage By Weight QuestionsGiven the weight of a patient and a dosage specified in

terms of weight, calculate the necessary dosage. These problems are a type of pediatric dosage calculations.

Formula:

Weight in Kg * Dosage Per Kg =  Y (Required Dosage)

Example: A doctor orders 200 mg of Rocephin to be taken by a 15.4 lb infant every 8 hours. The medication label shows that 75-150 mg/kg per day is the appropriate dosage range. Is this doctor's order within the desired range?

Cont…Weight in Kg * Dosage Per Kg =  Y (Required Dosage)

Convert 15.4 lb to kg. lb → kg    ( ÷ by 2.2 )

15.4 lb ÷ 2.2 = 7 kg

7 kg * 75 mg/kg =  525 mg (Minimum Desired Dosage)

7 kg * 150 mg/kg =  1,050 mg (Maximum Desired Dosage) 24 hours in one day and the medication is ordered every 8 hours.

24 hrs / 8 hrs = 3 times per day doctor ordered medication

200 * 3 = 600 mg ordered per day

600 mg is within the desired range of 525-1,050 mg

Yes doctor has ordered a dosage within the desired range. 

Cont…Example: Solumedrol 1.5 mg/kg is ordered for a child

weighing 74.8 lb. Solumedrol is available as 125 mg / 2mL. How many mL must the nurse administer?

Weight in Kg * Dosage Per Kg =  Y (Required Dosage)

Convert 74.8 lb to kg. lb → kg    ( ÷ by 2.2 )

74.8 lb ÷ 2.2 = 34 kg

34 kg * 1.5 mg/kg =  51 mgThis is now an ordinary Mass/Liquid For Liquid Question. 51

mg is ordered and the medication is available as 125 mg / 2 mL.

Ordered Have x Volume Per Have =  Y (Liquid Required)

51mg/125mg x 2 mL = 0.82mL

Summary

Developmental changes in body composition, body proportions and relative mass of the liver and kidneys affect pharmacokinetics of a drug among different ages (e.g. neonates, infants, children and adolescents).

The capacity for drug metabolism and elimination is the greatest between the first and second years of life when the size of the kidney and liver (relative to body weight) are at their maximum.

Cont…Remember that body surface area (relative to

body mass) is greatest in the infant and young child (as compared to the older child and adult) and thus, consideration must be given to potential systemic absorption of topically applied drugs.

The loading dose of a drug is primarily related to its volume of distribution, whereas the maintenance dose is a function of drug clearance.

Cont…Clearance of most drugs is primarily dependent on

hepatic metabolism, with the excretion of drug and metabolites completed by the kidneys (and to a lesser extent, the liver).

In general, between 1 year of age and puberty, hepatic and renal function is not only equal to, but may exceed, normal adult levels of functioning.

Children of the same age come in many different sizes. Always calculate drug dosages in mg/kg (especially among children less than 20 kg) and adjust the dose to the available preparations.

Cont…

In asthma management it is imperative to match the correct medication with the appropriate drug delivery device and the child's development.

The ideal medication is one that tastes good, is only given once a day, does not require refrigeration, comes in the right strength and is cheap, safe in kids and highly effective. Unfortunately, this combination does not exist; choose the closest option.