Journal of pain and symptom management 2017 07 12() pii S0885-3924(17)30264-6
The lack of knowledge of the accurate conversion ratio (CR) between intravenous (IV) and oral hydromorphone and opioid rotation ratio (ORR) between IV hydromorphone and oral morphine equivalent daily dose (MEDD) may lead to poorly controlled pain or overdosing in cancer inpatients. We aimed to determine the CR and ORR from IV hydromorphone to oral hydromorphone and MEDD (obtained from oral morphine and oxycodone).
4745 consecutive inpatient palliative care consults during 2010-14 were reviewed for conversions from IV hydromorphone to oral hydromorphone, morphine or oxycodone. Patient characteristics, symptoms and opioid doses were determined in patients successfully discharged on oral opioids without readmission within 1 week. Linear regression analysis was used to estimate the CR or ORR between the 24 hour IV hydromorphone mg dose prior to conversion and the oral opioid mg dose used prior to discharge.
Among 394 patients on IV hydromorphone, 147 underwent conversion to oral hydromorphone and 247 underwent rotation to oral morphine (163) or oxycodone (84). The median (IQR) CR from IV to PO hydromorphone was 2.5 (2.14-2.75) with correlation of .95(P<.0001). The median ORR (IQR) from IV hydromorphone to MEDD was 11.46 (9.84-13.00) with correlation of .93(P<.0001). The median ORR was 11.54 in patients receiving <30mg of IV hydromorphone/day and 9.86 in patients receiving ≥30mg (P=.0004). CONCLUSIONS
Our study found that 1 mg of IV hydromorphone is equivalent to 2.5 mg of oral hydromorphone and 11.46 mg of MEDD. Hydromorphone at doses ≥ 30 mg/day may require a lower ORR to other opioids.