Comparative Evidence on Subcutaneous and Intravenous Opioid Administration in Palliative Care

Strategic Insights -

Palliative care for cancer patients often relies on parenteral opioid administration, but the optimal route remains uncertain. A recent study aimed to compare the effectiveness and safety of subcutaneous (SC) versus intravenous (IV) infusion with bolus doses of morphine in a randomized controlled trial. The study involved 60 hospitalised palliative care patients with cancer, who were randomly assigned to SC or IV infusion with bolus doses over 48 hours.

Key Takeaways:

  • The study found no statistically significant or clinically meaningful differences in effectiveness or safety between SC and IV morphine administration.
  • Mean time to final infusion rate was 20.4 hours for SC and 16.3 hours for IV (mean difference: 4.1 hours, 95% CI: -3.6 to 11.7; p=0.293).
  • Median time to effect from bolus doses was 20 min for SC and 15 min for IV (HR=1.08, 95% CI: 0.61 to 1.88; p=0.795), indicating no significant difference.
  • NRS scores decreased from 3.9 to 2.1 (SC) and 3.3 to 2.3 (IV).
  • Infusion rates increased from 2.4 to 3.3 mg/hour, and bolus doses from 4.6 to 6.6 mg.
  • The proportion of effective doses was similar between groups.
  • One IV patient developed catheter-related thrombosis and infection post-intervention.

Statistics:

  • 60 patients were enrolled in the study, with 30 in the SC group and 30 in the IV group.
  • The study had a 48-hour infusion period.
  • The mean infusion rate increased from 2.4 to 3.3 mg/hour, and bolus doses from 4.6 to 6.6 mg.
  • The median time to effect from bolus doses was 20 min for SC and 15 min for IV.

Sources:

  • "Subcutaneous Versus Intravenous Route Switch From Oral To Parenteral Morphine In Patients With Cancer: Randomised Controlled Trial" - BMJ Supportive & Palliative Care, 2025.
  • BMJ Publishing Group, British Medical Association House, Tavistock Square, London WC1H 9JR, England.
  • Akershus University Hospital, Department of Palliative Medicine, Lorenskog, Norway.
  • South-Eastern Norway Regional Health Authority (Helse Sør-Øst RHF), Grant, Espen Klingenberg, research nurse at the Department of Palliative Medicine.