Anticipatory Prescribing
This is the practice of literally anticipating what a patient’s symptom control needs might be and prescribing for these eventualities. This includes consideration of the most appropriate route of administration as when a patient is dying swallowing almost always becomes difficult. Prescriptions will cover the as needed medications (prn) and ongoing symptom control considering what they are/were taking when able to swallow, which may require a continuous subcutaneous infusion (CSCI). These will need to be prescribed on the hospital drug chart for inpatients but a community drug chart for those outside the acute hospital.
Symptoms and the subcutaneous medications used for these, which commonly develop in the last hours or days of life include:
Pain
- Opioids chosen per renal function and previous opioid exposure and tolerance
- Morphine sulphate 2.5mg -5mg (eGFR >60)
- Oxycodone 1mg-2mg (eGFR 30-60)
- Alfentanil 0.125mg-0.25mg (eGFR <30)
It is important to consider availability and familiarity of these medications e.g alfentanil is not commonly used in the community and can be difficult to source. Therefore a lower dose of oxycodone may be more appropriate in patients with eGFR <30 with close monitoring for toxicity
Nausea
- Haloperidol 0.5mg
- In Parkinson’s disease ondansetron 4mg may be considered but special care must be taken to monitor for constipation if used regularly
- Cyclizine 50mg can be given SC but can be irritant at the site of injection
- Usual choice is midazolam 2.5mg - 5mg.
- In some older patients there may be a paradoxical reaction to benzodiazepines, worsening agitation, and levomepromazine 6.25mg may be more effective
- If frank delirium present an antipsychotic (haloperidol) should be used with alone or in addition to midazolam
Respiratory tract secretions
- Hyoscine butylbromide (buscopan) 20mg
- Glycopyrronium 400 mcg may be preferred in heart failure
- Hyoscine hydrobromide is an alternative but as this crosses the blood brain barrier can cause delirium and drowsiness
Shortness of breath
- Morphine sulphate 1.25mg either prn or regular is recommended unless significant renal impairment in which case alternative opioids may be used, though there is less evidence of their effectiveness
Diabetes
- Type 1 Diabetes
- In the last few days of life can allow blood sugar readings >15 mmol/L if asymptomatic
- Once a patient is unconscious and/or not having any oral intake a reduction of insulin doses to 75% with a minimum of once daily blood sugar monitoring and titrate dose accordingly
- Generally will aim to continue a small dose of long acting insulin, even if only 1 unit for avoidance of DKA
- A decision to stop insulin should only be made with the involvement of the patient and/or those that care for them
- Type 2 diabetes
- Stop oral hypoglycaemic agents and blood sugar monitoring once patient is no longer taking oral medications
- If on insulin <15 units/24 hours consider stopping this
- If needing to continue insulin reduce dose to 75% usual and monitor blood sugars once a day titrating dose accordingly
- Hypoglycaemia (BM<4)
- Very common in final days of life as liver begins to fail and glucose reserves deteriorate, so may be a normal part of dying
- If on hypoglycaemic agents aim to reverse with oral glucose if alert or IM glucagon if not, the titrate medications