Rapid Titration With Intravenous Oxycodone for Severe Cancer Pain and Oral Conversion Ratio

Context: to assess a dose titration with intravenous oxycodone to achieve rapid pain relief of cancer pain of severe intensity. The second objective was to provide a conversion ratio with the oral route.

Methods: Cancer patients admitted for severe pain were prospectively assessed. At admission (T0) previous opioid doses were recorded. Edmonton symptom assessment scale (ESAS) was collected from T0 until the conclusion of the observation. Intravenous boluses of oxycodone were given until the initial signs of significant analgesia were detected. The effective dose was multiplied for six and given as intravenous continuous infusion. When the patient was considered stabilized the intravenous daily dose was converted to oral oxycodone using an initial ratio of 1:2. Subsequently, doses of oral oxycodone were changed according to the clinical situation.

Results: Twenty-nine patients were examined. A mean effective bolus dose of oxycodone was 9.5 mg (SD 8.0) allowed to achieve a meaningful pain relief in a mean of 10.4 minutes (SD 3.3). The mean initial and the final infusion doses were 51.0 mg/day (standard deviation 40.9) and 69.7 mg/day ( standard deviation76.6), respectively. A significant change in pain intensity was observed at the different time intervals (P<0.0005). Conversion to oral route occurred after a mean of 2.7 days (standard deviation1.2) of intravenous oxycodone. The final mean conversion ratio was 1:2,12 ( standard deviation0.36).

Conclusion: Rapid intravenous oxycodone dose titration resulted in rapid pain relief. The intravenous-oral conversion ratio of 1:2 is reliable. Further studies are necessary to confirm this preliminary observation.