Subcutaneous Hydromorphone Administration in Hospice Patients
Yes, hydromorphone can be given subcutaneously for pain relief in hospice patients and is actually preferred over morphine for parenteral use due to its greater solubility. 1
Routes of Administration for Opioids in Hospice
When hospice patients are unable to take medications orally, alternative routes must be considered:
- Preferred alternative routes: Rectal and subcutaneous 1
- Subcutaneous administration options:
- Bolus injections every four hours
- Continuous infusion 1
Hydromorphone specifically is recommended for parenteral use in countries outside Britain (where diamorphine is preferred) due to its greater solubility compared to morphine. 1
Advantages of Subcutaneous Hydromorphone
- Greater solubility: Makes it more suitable for subcutaneous administration than morphine 1
- Potency: On a milligram basis, hydromorphone is 8.5 times as potent as morphine when given intravenously 2
- Efficacy: Research has shown hydromorphone to be at least as effective as morphine when delivered by continuous subcutaneous infusion 3
Contraindications for Subcutaneous Administration
Subcutaneous administration may not be practical in patients with:
- Generalized edema, soreness, or sterile abscesses
- Erythema
- Coagulation disorders
- Very poor peripheral circulation 1
In these cases, alternative routes such as intravenous administration may be necessary.
Dosing Considerations
When converting from oral to subcutaneous administration:
- The relative potency ratio of oral morphine to subcutaneous morphine is about 1:2 1, 4
- For hydromorphone, similar conversion principles apply, accounting for its greater potency
Monitoring for Adverse Effects
Careful monitoring is essential when using subcutaneous hydromorphone, particularly for:
- Neuroexcitatory effects: Including tremor, myoclonus, agitation, and cognitive dysfunction 5, 6
- These effects are dose and duration-dependent, with significantly increased risk at higher doses and longer durations of therapy 6
Special Considerations for Renal Impairment
- Hydromorphone is metabolized to hydromorphone-3-glucuronide (H3G), which can accumulate in renal impairment 6
- Patients with renal insufficiency have H3G levels 4 times higher than those with normal renal function 6
- Consider lower doses and careful monitoring in patients with renal impairment
Practical Administration Tips
- For continuous subcutaneous infusion, hydromorphone can be delivered via infusion pumps
- For breakthrough pain, additional bolus doses can be programmed
- Regular assessment of the infusion site for signs of irritation or inflammation is important
In conclusion, subcutaneous hydromorphone is an appropriate and effective option for pain management in hospice patients who cannot take oral medications, with particular advantages in terms of solubility compared to morphine.