59: Morphine-Alfentanil Mixture vs Morphine Alone

Comparison of a Morphine-Alfentanil Mixture (Alfine) vs Morphine Alone Administered in the Recovery Room for Post Operative Analgesia ($5,520)

Grant awarded to Dr Mark Reeves (North West).

At the moment we most often use Morphine (a narcotic) to treat any pain experienced immediately after surgery in the recovery room. The administration of Morphine is under the control of a nurse who regularly asks how much pain the patient has and then gives Morphine as needed.

We know that this is a safe and effective way of treating any acute pain, however, it can take some time for Morphine to work and so we are testing to see whether a new form of pain relief, a mixture of Morphine and another narcotic called Alfentanil, will work faster at relieving pain and be just as safe. This drug, Alfentanil, is from the same family of drugs as Morphine and is commonly used to produce pain relief during anaesthesia. It has also been tried for pain relief after surgery but although it works more rapidly, it does not seem to last long enough. A mixture of Alfentanil and Morphine in patients immediately after has been tried in an earlier study. Pain relief was achieved more rapidly than with Morphine alone and there were no signs of any increased risk of side effects. This study was not randomised or blinded so we wish to confirm this finding and study enough patients so we can be quite certain of its safety.

In this study we will compare this mixture of Alfentanil and Morphine with Morphine alone in patients in whom the anaesthetist has already decided to use Morphine for the treatment of pain in recovery. Patients will be recruited at pre-assessment clinic but only randomised if they need analgesia in the recovery room. Anaesthetists and recovery staff will be blinded to the allocation. Pharmacy will prepare and label the syringes A and B. Randomisaton is by computer via a website accessed through the recovery room.

Data recorded include patient demographics, operative information, amount of analgesia required and any side effects. Blood pressure, pulse sedation scores and adequacy of respiration will be recorded.

The major serious risk of opiods is respiratory depressions (slow breathing) and this will be monitored carefully in the study (as it is routinely in recovery) to look for any differences beween Alfine and Morphine.

Participation in this study is entirely voluntary and confidentiality will be maintained. The data will be identified before being sent to Guy Ludbrook at the Royal Adelaide Hospital for analysis with data being gathered there under the same trial period.