Prevalence and management of intrathecal morphine-induced pruritus in New Zealand Māori healthcare recipients

• Published in: British journal of pain 2018-02, Vol.12 (1), p.20-25
• Main Authors: Woods, Jennifer M, Lim, Anecita Gigi
• Format: Article
• Language: English
• Subjects: Original
• ISSN: 2049-4637; 2049-4645
• DOI: 10.1177/2049463717719773

Aims and objectives: The aim of this article was to determine whether the incidence of intrathecal morphine-induced pruritus (ITMI) was influenced by ethnicity, age or gender in relation to orthopaedic versus caesarean surgeries. Background: The use of intrathecal morphine for patients undergoing total hip and knee joint replacements and for lower segment caesarean sections (LSCS) has gained popularity worldwide since its introduction over 30 years ago. Several international studies show that morphine delivered via the intrathecal route is an effective and safe method of pain relief. However, while the beneficial effects of intrathecal morphine have been clearly documented in many studies, so also have the adverse effects, predominantly being nausea and vomiting, pruritus and respiratory depression. Pruritus is described as one of the most common adverse effects, with a reported incidence of 30–100%. Design: A retrospective study was conducted using data collected over a 21-month period on post-operative patients who had received intrathecal morphine as their post-operative pain management. Methods: A two-phased approach was undertaken. The study was conducted to determine the incidence of ITMI pruritus among two patient groups, New Zealand Māori and New Zealand European, 96 subjects in total, and if treatment was received. Results: The findings revealed significant ethnic disparities whereas New Zealand Māori had a significantly higher rate of ITMI pruritus than New Zealand European, New Zealand Māori experienced the pruritus with more intensity and are less likely to be treated for it. Conclusion: Increased international knowledge and awareness for health professionals around the diversities of ethnicity and associated pharmacogenetics playing a significant role in patient response to opioid therapy can lead to improved overall care and patient satisfaction.