At the end of life, patients often experience symptoms such as pain, excess secretions and agitation. To reduce distress and ensure timely treatment, anticipatory medications are prescribed in advance of these symptoms developing.
There are four main classes of anticipatory medications: analgesia, anti-emetic, anxiolytic and anti-secretory.
This article will cover how to prescribe anticipatory medications for patients nearing the end of life.
Anticipatory medications are prescribed as subcutaneous injections as patients nearing the end of life may not be able to take oral medications. These should be given as needed (PRN) rather than regularly.
When prescribing anticipatory medications, the following should be included: drug name, dose, route (subcutaneous), indication for each medication, frequency of delivery and maximum doses in twenty-four hours. This allows for regular reviews and safe levels of medication.
Unless the patient has already received the medications, it is recommended to start with a low dose and increase according to response.
Choice of medication and starting doses vary according to patient factors including past medical history, organ dysfunction and drug history. Local guidelines should also be consulted.
Aside from medication, other treatments (including non-pharmacological methods) should also be considered to manage symptoms. For example, providing psychological support, considering environmental factors for those who are agitated and using fans for breathlessness.
Pain can be caused by a variety of factors such as disease-related pain or pressure sores.
It is important to recognize pain, especially if the patient is less responsive and cannot communicate their symptoms.
Communicating with a family member, carer, or staff member who knows the patient can help recognize patterns of behavior that may indicate pain. These changes may include:
Common first-line agent for opiate naïve patients:
For patients already on a background dose of opioid medication, the PRN anticipatory dose is generally 1/6th of the total subcutaneous background dose in 24 hours.
Mr Y has been taking 30mg BD slow-release morphine but is now approaching the last days of life and is not able to swallow his usual medications. This is equivalent to 30mg SC morphine in 24 hours, and the PRN dose would be 5mg SC morphine (30/6).
Nausea and vomiting may be caused by constipation, medication side effects, or biochemical disturbance (e.g. hypercalcaemia).
Haloperidol 0.5 -1.5mg SC. Do not repeat within 4 hours, maximum dose 3mg in 24 hours.
Agitation may be caused by pain, medications (side effects and withdrawal), constipation, and urinary retention.
Detecting agitation in a patient relies on observing the patient and listening to those who are looking after them. Signs of agitation may include:
Midazolam 2.5 -5mg SC. Do not repeat within 1 hour, maximum 4 doses in 24 hours.
When levels of consciousness are reduced, patients may be unable to swallow or clear their normal respiratory secretions/saliva, which can lead to pooling in the upper respiratory tract. This may cause noisy breathing/a rattling noise as air passes over the pooled secretions. Reassurance and repositioning the patient may be helpful.
Hyoscine Butylbromide 20mg SC. Do not repeat within 1-hour, maximum dose 120mg in 24 hours
Syringe drivers are small battery-powered pumps used to deliver medications as a continuous subcutaneous infusion (CSCI) over a 24-hour period. A syringe containing the appropriate medications is attached to a needle that is placed under the skin (into the subcutaneous tissue), usually on the thigh, upper arm, or abdomen.
Indications for use of a syringe driver in patients nearing the end of life include requiring two or more doses of any one of the anticipatory medications in a 24 hour period, and being unable to take oral medications that need replacing (e.g. modified release opiates, anti-epileptic medications).
Continuous infusion provides a constant level of medication to the patient, which helps to achieve better symptom control.
Only medications that a patient has required are put into a syringe driver. Therefore, regular reviews are important as they may still require further ‘as required’ doses of medication on top of those in the syringe driver. These may be the same medications they are already receiving or one of the other anticipatory medications.
Mrs X has pancreatic cancer and is in the last days of life. She has developed noisy breathing and agitation in the last 24 hours. She has required 3 x 20mg doses of hyoscine butylbromide and 2 x 2.5mg doses of midazolam. A syringe driver containing 60mg of hyoscine butylbromide and 5mg of midazolam over 24 hours is commenced.
You review Mrs X 24 hours after starting her syringe driver as above. Her family report that she has continued to have some noisy breathing, requiring two further doses of 20mg hyoscine butylbromide. She has also had 1 x 5mg midazolam for agitation and 1 x 5mg morphine sulphate for pain.
Therefore, you prescribe a new syringe driver containing 100mg hyoscine butylbromide, 10mg midazolam and 5mg morphine sulphate.
Separate drug charts are usually used for prescribing syringe drivers. Many drugs can be mixed together safely in a syringe driver, but it is important to check compatibility. Further details can be sought from local guidelines, pharmacists or the local palliative care team. When setting up a syringe driver, most drugs are diluted in water for injection.
Pain, agitation and syringe pumps are important topics in palliative care. The following resources provide helpful information on these topics:
