Applying realistic medicine to intrathecal opioid utilisation in Scotland: do we have a standardised approach?

Intrathecal opioids (ITOs) are commonly administered as part of a multimodal anaesthetic strategy for a variety of surgical procedures. The evolution of laparoscopic surgical techniques has seen the popularity of ITOs increase as they are effective, well tolerated and lack the cardiovascular side effects associated with epidural infusions. The risk of delayed respiratory depression remains a concern; therefore, high-quality post-operative monitoring is vital. The evidence regarding the practicalities of ITO administration such as opioid dose, type, side effect prevalence and ideal post-operative care arrangements are sparse. As such, a variety of clinical opinion has been generated. In order to quantify this variation within Scotland, we devised a short telephone questionnaire regarding ITO utilisation. We contacted 16 acute surgical sites. Of these, 14 confirmed regular utilisation of ITOs. Our survey demonstrated significant variability in practice. Both diamorphine and morphine are utilised, but no centre could provide a reason to justify the choice of one over the other. The commonly administered dose range for both agents ranged between 100 and 1100 µg. Most centres employed post-operative monitoring geared towards the detection of delayed respiratory depression but this was not unanimous. Each centre had a variation on what observations nursing staff were expected to complete in the post-operative period. Itch and nausea were not encountered frequently. Two centres experienced at least one episode of delayed respiratory depression which was detected and treated with no patient harm. In the report to the Scottish Government, 'Realistic Medicine', by the Chief Medical Officer, the need to reduce unnecessary variation in practice and outcomes is highlighted. We believe that a national sprint audit would gather sufficient prospective data to further determine whether a correlation exists between side effect profile and ITO utilisation practice. We hope this would help form a consensus and guide a standardised approach.