International Journal of Clinical Pharmacy

, Volume 38, Issue 5, pp 1069–1074 | Cite as

Sources and magnitude of error in preparing morphine infusions for nurse-patient controlled analgesia in a UK paediatric hospital

  • Asia N. RashedEmail author
  • Stephen TomlinEmail author
  • Virginia Aguado
  • Ben Forbes
  • Cate Whittlesea
Short Research Report


Background Administering nurse/patient controlled analgesia (N/PCA) to children requires complex dose calculations and multiple manipulations to prepare morphine solutions in 50 mL syringes for administration by continuous infusion with additional boluses. Objective To investigate current practice and accuracy during preparation of morphine N/PCA infusions in hospital theatres and wards at a UK children’s hospital. Methods Direct observation of infusion preparation methods and morphine concentration quantification using UV–Vis spectrophotometry. The British Pharmacopoeia specification for morphine sulphate injection drug content (±7.5 %) was used as a reference limit. Results Preparation of 153 morphine infusions for 128 paediatric patients was observed. Differences in preparation method were identified, with selection of inappropriate syringe size noted. Lack of appreciation of the existence of a volume overage (i.e. volume in excess of the nominal volume) in morphine ampoules was identified. Final volume of the infusion was greater than the target (50 mL) in 33.3 % of preparations. Of 78 infusions analysed, 61.5 % had a morphine concentration outside 92.5–107.5 % of label strength. Ten infusions deviated by more than 20 %, with one by 100 %. Conclusions Variation in morphine infusion preparation method was identified. Lack of appreciation of the volume overage in ampoules, volumetric accuracy of different syringe sizes and ability to perform large dilutions of small volumes were sources of inaccuracy in infusion concentration, resulting in patients receiving morphine doses higher or lower than prescribed.


Analgesia Children Medication Error Morphine Nurse Opioid intravenous infusions Preparation Paediatrics United Kingdom 



Authors wish to thank HCPs participated, and the project steering group members, in particular, Dr Caroline Davies, Hazel Foale and Sara Arenas for helping in facilitating this study. We thank QC staff for undertaking morphine assay.


This project was funded by the Health Foundation (SHINE 2012 programme). The Health Foundation is an independent charity working to continuously improve quality of healthcare in UK.

Conflicts of interest

ANR was funded by the Health Foundation. Other authors declared no financial interests.

Supplementary material

11096_2016_369_MOESM1_ESM.docx (12 kb)
Supplementary material 1 (DOCX 12 kb)


  1. 1.
    Ross LM, Wallace J, Paton JY. Medication errors in a paediatric teaching hospital in the UK: five years operational experience. Arch Dis Child. 2000;83:492–7.CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    National Patient Safety Agency (NPSA). Intravenous morphine administration on neonatal units: signal. 25th March 2011, available from: Accessed 08 Mar 2015.
  3. 3.
    Taxis K, Barber N. An ethnographic study of incidence and severity of intravenous drug errors. BMJ. 2003;326:684–7.CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Taxis K, Barber N. Causes of intravenous medication errors: and ethnographic study. Qual Saf Health Care. 2003;12:343–8.CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Cousins DH. Medication errors. In: Jacqz-Aigrain E, Choonara I, editors. Paediatric clinical pharmacology. Lausanne, New York: FontisMedia SA and Taylor & Francis Group; 2006. p. 254.Google Scholar
  6. 6.
    Mcleroy PA. The rule of six: calculating intravenous infusions in a pediatric crisis situation. Hosp Pharm. 2004;29:939–40.Google Scholar
  7. 7.
    Department of Health. British pharmacopoeia: morphine sulphate injection. London: TSO; 2012.Google Scholar
  8. 8.
    Parshuram CS, Ng GY, Ho TK, Klein J, Moore AM, Bohn D, et al. Discrepancies between ordered and delivered concentrations of opiate infusions in critical care. Crit Care Med. 2003;31:2483–7.CrossRefPubMedGoogle Scholar
  9. 9.
    Aguado-Lorenzo V, Weeks K, Tunstell P, Turnock K, Watts T, Arenas-Lopez S. Accuracy of the concentration of morphine infusions prepared for patients in a neonatal intensive care unit. Arch Dis Child. 2013;98:975–9.CrossRefPubMedGoogle Scholar
  10. 10.
    Stucki C, Sautter AM, Wolff A, Fleury-Souverain S, Bonnabry P. Accuracy of preparation of i.v. medication syringes for anesthesiology. Am J Health Syst Pharm. 2013;70:137–42.CrossRefPubMedGoogle Scholar
  11. 11.
    Rashed AN, Wong ICK, Cranswick N, Hefele B, Tomlin S, Jackman J, et al. Adverse drug reactions in children—international surveillance and evaluation (ADVISE): a multicentre cohort study. Drug Saf. 2012;35:481–94.CrossRefPubMedGoogle Scholar
  12. 12.
    Bhambhani V, Beri RS, Puliyel JM. Inadvertent overdosing of neonates as a result of the dead space of the syringe hub and needle. Arch Dis Child Fetal Neonatal Ed. 2005;90:F445.CrossRefGoogle Scholar
  13. 13.
    Rashed AN, Forbes B, Tomlin S, et al. Current practice of preparing morphine infusions for nurse/patient controlled analgesia in a UK paediatric hospital: healthcare professionals’ views and experience. Eur J Hosp Pharm. 2016;. doi: 10.1136/ejhpharm-2015-000866 (Epub ahead of print).Google Scholar
  14. 14.
    Larsen GY, Parker HB, Cash J, et al. Standard drug concentrations and smart-pump technology reduce continuous-medication-infusion errors in paediatric patients. Paediatrics. 2005;116:e21–5.CrossRefGoogle Scholar

Copyright information

© Springer International Publishing 2016

Authors and Affiliations

  1. 1.Institute of Pharmaceutical ScienceKing’s College LondonLondonUK
  2. 2.Pharmacy Department, Evelina London Children’s HospitalGuy’s & St. Thomas’ NHS Foundation TrustLondonUK
  3. 3.School of Medicine, Pharmacy and HealthDurham UniversityDurhamUK

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