1. Are prescribed doses of medicine for children measurable?
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable?
Morecroft CW, Liverpool John Moores University
Gill A, Alder Hey Children’s NHS Foundation Hospital Trust
Caldwell NA, Wirral University Teaching Hospital Foundation Trust
Wood R, Liverpool John Moores University
Crolla J, Liverpool John Moores University
Antwi-Boasiako L, Liverpool John Moores University

2. Are prescribed doses of medicine for children measurable? Objective
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable? Objective 
What proportion of prescribed doses of liquid medicine for children and neonates are measurable?

3. Are prescribed doses of medicine for children measurable? Method
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable? Method 
Liquid medications prescribed to paediatric/neonatal inpatients at two hospitals.
Five week period January/February 2011.
Name, strength and prescribed dose of drug, demographics, volume and whether dose measurable in single syringe.

4. Are prescribed doses of medicine for children measurable? Results
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable?  Results
1599 doses for 431 patient records reviewed.
196 doses (12.3%) immeasurable.
29 (14.8%) within neonates, 58 in infants (25.6%), 81 in children (41.3%) and 28 in adolescents (14.3%).

5. BNF category of immeasurable doses
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
BNF category of immeasurable doses
Analgesia (n=49)
Infection (n=67)
Gastro-intestinal (n=18)
Ibuprofen (n=14)
Ceftazidime (n=6)
Ranitidine (n=8)
Morphine (n=4)
Cefuroxime (n=5)
Domperidone (n=3)
Paracetamol (n=26)
Clindamycin (n=6)
Ondansetron (n=5)
Naloxone (n=4)
Flucloxacillin (n=4)
Miscellaneous (n=34)
Antiepileptic (n=7)
Gentamicin (n=9)
Chlorphenamine (n=4)
Phenobarbital (n=3)
Metronidazole (n=5)
Chloral hydrate (n=3)
Phenytoin (n=3)
Teicoplanin (n=5)
Caffeine (n=6)
Corticosteroid (n=21)
Tobramycin (n=7)
Pamidronate (n=3)
Dexamethasone (n=18)
Oseltamivir (n=3) 5

6. Examples of immeasurable doses
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Examples of immeasurable doses  
Drug
Concentration
Dose (mg)
Volume (mL)
Syringe (mL)
Cefotaxime inj
250mg/mL
580
2.32
2.5
Ceftazidime inj
200mg/mL
675
3.375 5
Gentamicin inj
80mg/2mL
66.5
1.6625
Hydrocortisone inj
100mg/2mL
1.6
0.032 1
Metronidazole po
200mg/5mL
175
4.375
Morphine po
10mg/5mL
1.25
Phenobarbital inj
60mg/mL
Phenytoin po
30mg/5mL 6

7. Immeasurable doses % Graduations 196 100
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Immeasurable doses and measuring device
Syringe size
Immeasurable doses %
Graduations
1mL 49
25.0
0.01mL
2.5mL 55
28.1
0.1mL
5mL 44
22.4
0.2mL
10mL 33
16.8
0.5mL
20mL 14
7.1
60mL 1
0.5
Total
196
100

8. Are prescribed doses of medicine for children measurable? Discussion
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable? Discussion
If prescribed dose cannot be measured, and an almost dose is given, is it a prescribing or administration error .... or not an error at all?
Ideally measurability should be considered by prescriber or be reviewed by pharmacist prior to administering first dose.
Pharmacists often endorse prescriptions with volume to be administered but this may introduce error. 8

9. Are prescribed doses of medicine for children measurable? Discussion
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable? Discussion
Resolving problem complicated as concentrations of medicine vary widely and dose rounding needs to take account of graduations on syringe. Most people do not know graduations?
Some medicines are more likely to be immeasurable.
To make immeasurable dose measurable, by approximation, might have serious impact on patient for those drugs with narrow therapeutic index/window. What are the rules?

10. Conclusion: integrate knowledge base into e-prescribing systems.
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Johnson et al. “Automated dose rounding recommendations for pediatric medications. Pediatrics 2011; 128: e
Objective: establish best practice and create interoperable rounding knowledge base combining best practice and dose rounding information.
Method: literature review and expert interview. Consensus about rounding tolerance through Delphi process.
Results: 3 categories defined. A. meds rounded judiciously to retain intended effect eg furosemide. B. meds rounded with attention to potential unintended effect eg steroids. C. meds with narrow therapeutic effect and high risk of toxicity eg digoxin.
Conclusion: integrate knowledge base into e-prescribing systems. 10

11. LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable? Recommendation
Further research required to explore measurability of doses of liquid medicine and relationship with those with narrow therapeutic window. 11

12. Are prescribed doses of medicine for children measurable? Conclusion
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Are prescribed doses of medicine for children measurable? Conclusion
1 in 8 prescribed doses of liquid medicine cannot be measured.
We need to fix it! 12

13. Oh bother! I get so mixed up. Did he say 2.34643mL or 6.43234mL?
LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences
Oh bother! I get so mixed up. Did he say mL or mL? 13

14. LIVERPOOL JOHN MOORES UNIVERSITY
School of Pharmacy and Biomolecular Sciences