Table 1 Inclusion and exclusion criteria

Inclusion criteria:

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Ages 1 – 21 years

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≥10 kg and ≤70 kg

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Known sickle cell disease presenting with severe pain

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Written informed consent, ideally from both parents (and assent, where appropriate), obtained prior to painful crisis (for example, in Haematology clinic)

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Verbal consent (and assent, where appropriate) obtained at the time of the painful crisis in the ED

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Hospital admission required for painful crisis

Exclusion Criteria:

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Patient has received parenteral narcotic analgesic within 4 hours of ED presentation

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Oxygen saturations below 95% on initial assessment

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Altered conscious state as defined by a Glasgow Coma score less than 15

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Contraindications to fentanyl/morphine usage

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Inability to secure IV access

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Patient has participated in another clinical trial involving an Investigation Medicinal Product (IMP) within 4 weeks of dosing, or is currently enrolled in another clinical trial involving an IMP, or has been previously enrolled in this trial

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Patients who have any condition that would make him/her, in the opinion of the Investigator or Sponsor, unsuitable for the study, or who are, in the opinion of the Investigator, not likely to complete the study for any reason

•

Blocked or traumatised nose