Pain in palliative care
Until recently, it was widely believed that children, particularly young children, experienced less pain than adults. Many clinical studies have negated these myths showing that children and adults experience similar degrees of pain. 1
One of the great fears of children and families in the setting of terminal illness is that of unrelieved pain. However in the vast majority of circumstances it is possible to effectively control pain with analgesic/pain relieving medications. Opioid addiction is
another concern for families, and some health professionals. Again, this fear can be allayed because it has been shown that patients receiving properly titrated doses of analgesia do not become addicted.2 Parents and health professionals sometimes confuse
tolerance (the need for escalating doses to achieve the same therapeutic effect) with addiction. A patient's need for increasing doses of opioids is related to tolerance and disease progression, and should not be seen as impending addiction. The dose should be
increased according to an individual's need. It is important to anticipate and discuss concerns and fears about the use of opioid analgesics early in the terminal phase of the child's illness to ensure that misconceptions are addressed.
Assessment of pain
Self-report of pain levels is the "gold standard" of pain assessment in older children and adults. The evaluation of pain in children however is dependent on the child's age and developmental stage. Pain measurement and pain assessment are not the same thing
and while it may be possible to determine the site of pain and make some estimation of its severity, understanding its character and radiation is often more difficult. Children need to understand what is being asked of them so wherever possible their own terminology
should be used, e.g. using the word 'sore' or 'hurt' instead of pain. The response they give might also depend on who is asking the question and what the consequences may be. Children who are fearful of receiving a painful injection or unpleasant tasting medication
may not admit to pain. Health professionals need to utilise a number of parameters to adequately assess pain in children. Simple observation is extremely useful as changes in activity level and behaviours such as irritability or withdrawal may indicate
discomfort. It is important to remember however that the behaviour of a child in chronic pain differs from that of a child in acute pain. The latter tend to be more demonstrative and vocal while children in chronic pain may appear quiet, withdrawn, lack interest
in activities or surroundings, be reluctant to move, have clingy behaviour or whinging, or have difficulty sleeping. 3
Pain assessment in children should be multidimensional taking into account:
Self report. For children over the age of four years a number
of useful pain scales exist. Examples include;
- Visual analogue scales eg. Pain ladders and thermometers
- Faces Pain Scale a series of faces depicting varying levels of discomfort 4
- Oucher scale a series of photographs depicting varying levels of discomfort 5
- Poker Chip Tool the child is asked to hand the examiner the number of poker chips which corresponds to the degree of pain (max 4)
- Body outline the child is asked to use colour to indicate the site and severity of their pain
- Pain questionnaires these are useful in older children and adolescents
- Parental report. Parents know their children very well and are able to provide valuable interpretations of behaviour. However, parents tend to under-estimate pain in their children so their observations should never form the sole basis of pain assessment.
6
- Medical staff observations of the child's behaviour a range of age-appropriate observation scales have been devised and validated scientifically for acute pain assessment but are also used for children with chronic pain.
- Changes in blood pressure and heart rate may provide some indication of pain but may be influenced by a number of other factors especially anxiety/fear.
- Other influences such as past pain experiences and coping strategies, the meaning of the pain to the child and family and their emotional state.
Principles of pain
management
- Comprehensively assess the pain and address all the
factors which may be contributing to the pain experience (eg. anxiety, other symptoms, family stress)
- Discuss the management strategy with the family and address potential anxieties
- Utilise a multimodal approach incorporating physical therapies such as massage, TENS machines and splints and non-pharmacological techniques such as music/play therapy, story book reading, hypnotherapy, guided imagery or direct to other therapies where
appropriate.
- Utilise the least invasive route of medication administration. The oral route is preferred as it causes minimal discomfort or disruption to the child and absorption from the gastrointestinal tract is good.
- In the palliative care of children, there is NO role for intramuscular analgesia.
- Administer analgesics regularly (by the clock) to control constant or frequent bouts of pain
- Minimise the number of doses required per day. Sustained release (or slow continuous) preparations of opioids are available in a variety of preparations.
- Plan ahead for exacerbations and crises and give immediate release medications for this or prior to pain inducing activities.
- Titrate the dose of opioid to effect. There is no maximum dose as such. The correct dose is that which relieves the patient's symptoms with minimal side effects.
- Prophylactically prescribe regular laxatives when using
opioids.
- Monitor the response to treatment, and review the opioid dose regularly.
- Seek advice if the pain is not quickly controlled
Resources
A Practical Guide to Palliative Care in Paediatrics
References
1/ Anand KJS, Grunau RVE, Oberlander TF. Developmental character and long-term consequences of pain in infants and children. Child Adolesc Psychiat North Am 1997; 6: 703.
2/ Woodruff R. Palliative Medicine: Symptomatic and supportive care for patients with advanced cancer and AIDS. Asperula. Melbourne.1993
3/ Gauvain-Piquard A, Rodary C, Lemerle J. L'atonie psychomotrice: signe majeur de doleur chez l'enfant de moins de 6 ans. J Parisiennes Pediatrie 1988;249-52.
4/ Bieri D, Reeve RA, Champion GD, et al. The faces pain scale for the self-assessment of the severity of pain experienced by children: development, initial validation, and preliminary investigations for ratio scale properties. Pain 1990; 41: 139-150.
5/ Beyer JE, Wells N. The assessment of pain in children. Pediatr Clin North Am 1989; 36: 837-54.
6/ Chambers CT, Reid G, Craig KD, McGrath PJ, Finley GA. Agreement between child and parent reports of pain. Clin J Pain 1998; 14: 336-342.