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Te recent PainSA conerence held in conjunction with the Inter-national Association o the study o Pain, Arica Association or thestudy o Pain, NeuroPsig and the London Pain Consortium, presentedcurrent physiological evidence o the importance o neuronal and

synaptic activities involved in generating pain. Te physiologicalevidence supports the inclusion o medication previously consideredas co-analgesics or adjuvant analgesics as primary analgesics. Tisarticle looks at the assessment and management o pain in the palliativecare setting and the current recommendations or the management oneuropathic pain.

Pain in the palliative care setting can be caused by the illness itsel,

the treatment (radiotherapy, chemotherapy, antiretroviral treatment),concurrent disorders (tension headaches, urinary tract inection) orby general debility.1 Tus a very careul assessment and a multimodalapproach and understanding o pain are required.

Physiologically the diferent types o pain can be described asnociceptive (arthritis, cellulitis),2 visceral (pancreatitis, peptic ulcers),neuropathic (herpes zoster, post-stroke pain) and mixed pain, acombination o the other types o pain ound in certain disease statessuch as AIDS and cancer.

Many patients and health care proessionals do not distinguishthe pain experience rom nociception, which describes the neuralprocesses involved in the transduction o noxious stimuli.3 Pain in thepalliative care setting is not purely a nociceptive or physical experiencebut involves all aspects o human unctioning: personality, afect,cognition, behaviour, and social relations.4 Experimental evidenceshows that acute persistent pain may promote biochemical andphysiological changes in the peripheral and central nervous system,which may promote the continuation o pain.5 Chronic pain (lastinglonger than 3 months) has a negative impact on quality o lie 6 andleads to anxiety, depression and sleep disorders. Because pain inpalliative care is multidimensional, a multimodal approach is neededto address both the physical and the physiological actors (Fig. 1).

Pin ssssmntTe most important element o pain assessment in palliative care isto establish a good rapport with the patient and to show empathy andunderstanding o his/her pain and sufering. Encourage the patient todo most o the talking by asking open-ended questions (ell me aboutyour pain) and then zone in on more specic questions (able I).Specic questions about the location, intensity, character and temporalprole o the pain, exacerbating actors and concomitant symptomswill help the clinician distinguish between the diferent types o pain.7Neuropathic pain is classically described as pricking, tingling, pinsand needles, electric shocks or shooting, hot or burning, numbness,pain evoked by light touch or pain evoked by change in temperature.Tis type o pain is typically conned to a specic set o dermatomes.Nociceptive pain may be somatic or visceral pain. Somatic pain istypically well localised and is elt in the supercial cutaneous or deepermusculoskeletal system. Visceral pain is usually poorly localised, oendescribed as deep squeezing and/or pressure and may be associatedwith nausea, vomiting and diaphoresis, especially when acute. Visceralpain can be reerred to cutaneous sites away o the lesion (shoulderpain with diaphragmatic lesions).8 Te intensity o the pain can bemeasured by using visual analogue, drawings and verbal descriptors. Asimple tool which is used in countries with varying degrees o literacyand numeracy is a closed st or no pain and each digit indicatingan increasing degree o pain up to ve or the maximum. During theassessment the clinician must also determine how the pain afects the

Advances in pain control in palliative care

Pain in palliative care needs to be careully assessed beore treatment.

ReNe KRaUSe,MB ChB, MFamMed, MPhil (Palliative Medicine)Family Physician, St Lukes Hospice, Cape own

Rene Krause has been working in palliative care for the past 7 years. She worked in Bethesda Hospice and in Harry Comay B hospital with special interest in MDR

B. For the past 3 years she has been working at St Lukes Hospice, Kenilworth, Cape own, where she is the doctor in a 10-bed IPU which mainly concentrates on

cancer patients and pain control.

JaNeT STaNfoRD, MB ChB, MPhil (Maternal and Child Health), MPhil (Palliative Medicine)Medical Ocer and CEO, Knysna Sedgeeld Hospice

Janet Stanford is married to John Stanwix, economist turned farmer. She has 3 children Emily, Ben and Louisa and enjoys beekeeping and yoga.

Corresponding author: Rene Krause (renek@stlukes.co.za)

Te physiological evidence supportsthe inclusion o medication previously

considered as co-analgesics or adjuvantanalgesics as primary analgesics.

Pain in the palliative care setting is notpurely a nociceptive or physical experience

but involves all aspects o humanunctioning: personality, afect, cognition,behaviour and social relations

Cognition

Meaning of ain

Emotion

Suffering

Socioenvironment

Social suort

NOCiCEpTiON

psycho-

social

theraies

Somatic

theraies

Fig. 1. Te multidimensional nature of pain in terminal illness.

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eect. I possible it is helpul to interviewthe amily/carer, especially in the cognitivelyimpaired patients, but not to rely only onproxy reports.

A amily member in pain exercises a negativeeect on the dynamics o a amily. Whenpatients are acing a lie-threatening illnessthe meaning and understanding o pain andsuering must be explored with the amily.Family caregivers experiences with painbegin with their perception o the patients

lead to long-term emotional distress in thecaregiver.9

examinationExamination o the patient should startwhen the patient walks into the cliniciansoce. Look or non-verbal signs, e.g. thepatient who keeps his arm warm or pullshis shirt away rom his body. Te physicalexamination should be to the point and asnon-invasive as possible. In neuropathicpain the clinician should try to localise thelesion by doing a systemic neurologicalexamination. Tis should include a sensoryexamination to reveal somatosensorydysunction, a motor assessment (musclestrength, tonus and fuidity o movement)and an examination o the tendon refexesand cranial nerves. It is also important toassess the peripheral autonomic nervous

ManagmntOnce the clinician has a clear understandio the type o pain, its severity, possibcause and emotional component o tpain, pharmacological and non-pharmcological interventions can be implementReversible actors should be addressed ana clear explanation o the cause o the pa

given to both the patient and the caregivreatment options must be discussed wboth the patient and the caregiver so ththey become active participants in the pacontrol. It is also important to establirealistic goals with the patient and to explathat individuals respond dierently medication and treatments.

Respecting patient autonomy can be vedicult or clinicians when seeing thepatients suer pain. However, when patienare acing multiple losses, as most palliaticare patients are, it is very important or tpatient to maintain control o his/her pamanagement or as long as possible. Patienmay be earul o using morphine reasons that need to be sensitively explorand explained so that patients can take uadvantage o modern pain control methowithout signicant side-eects.

Te World Health Organization has creat

a stepwise approach to the managemeo cancer pain known as the analgeladder (Fig. 3).10 Tis analgesic laddapproach is not an evidence-based guidelinbut provides a systemic approach to tmanagement o cancer pain,11 especially resource-limited areas.

Pain contr

Somatic pain is typicallywell localised and is elt inthe superfcial cutaneousor deeper musculoskeletal

system.

Te physical examinationshould be to the point and

as non-invasive as possible

Tabl I. clinial assssmnt of pain2

Believe the patients complaint

Take a careful history of the pain complaint to place it temporally in the progression of the

patients illness

Assess the characteristics of each pain (site, referral pattern, aggravating and relieving factors

and impact on daily living)

Clarify the temporal aspects of the pain (acute, chronic, intermittent)

List and prioritise each pain complaint Evaluate response to previous treatment

Evaluate the psychological state of the patient and the eect of pain on it

Perform a careful medical and neurological examination

Order and review appropriate diagnostic test

Individualise the treatment to the patients circumstances and create realistic goals

Provide continuity of care

Empower patient and family caregiver to manage the pain, especially breakthrough pain

Reassess the patients pain response to treatment and compliance

percetion of the atient's

ain

pain exerience

Exression

Caregiver

burdenAssociated

emotions (e.g.

anxiety, guilt,deression)

Suffering

prior ain exerience

Culture

Relationshi

Meaning of ain

Understanding of ain

Fig. 2. Caregivers experience of pain. (Adapted from Ferrell BR et al. Oncology Nursing Forum1991;18:1315-1321.)

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Adjuvant drugs or co-analgesia describe anydrugs that have a primary indication otherthan pain, but are analgesic in some painulconditions (able II).13 Te diversity andunderstanding o these drugs has developedover past decades and some o these drugsare now seen as rst-line therapy or certainkinds o pain.

advnes in pin mngementTere is extensive literature regarding thephysiology o the central and peripheralmechanisms o neuropathic pain andits management. Te injury o a neuronproduces change in the excitability in the

discharges. Tree actors seem responsible:up-regulation o voltage gated sodiumchannels, down-regulation o potassiumchannels and possibly a reduction in thethreshold o transient receptor potential(RP) transducer heat-sensitive channelsso that they can be activated at bodytemperature.13 Tis ectopic activity may thendirectly initiate spontaneous sensation such asburning pain, paraesthesia and dysthethesia.N-methyl-D-aspartate (NMDA) receptorsalso play a major role in hyperalgesia and theenhancement o allodynia, a phenomenontermed central sensitisation.14 Ketamine, awell-known NMDA receptor antagonist, has

central nervous system side-eects. A majorway through which NMDA receptors workis through the infux o calcium channelsand by decreasing transmitter release withcalcium channel blockers (N type) and2- binding drugs, pain reduction can beachieved.

Te International Association or the Study

o Pain (IASP) has developed new treatmentguidelines or the management o neuropathicpain15 guided by improved understanding othe physiology o neuropathic pain and itsmanagement. It is especially in the treatmento neuropathic pain that new treatmentrecommendations have to be consideredas rst-line therapy. Factors to considerwhen choosing one neuropathic drug aboveanother are: pain physiology; side-eects othe drugs; drug interactions; co-morbiditiesthat can be alleviated by non-analgesic eect(e.g. depression, anxiety); cost and risk oabuse and over-dosage. In palliative care

time becomes a very important actor andcombination therapy may be needed orrapid onset o pain relie.

Pain control

Tble II. common nlgesis for ner pin

Drugs Inditions

Non-steroidal anti-infammatory drugs Bone pain, so-tissue inltration, hepatomegaly

Corticosteroids Raised intracranial pressure, nerve compression,

so-tissue inltration, hepatomegaly

Bisphosphonates Bone pain

Antidepressants, anticonvulsants Neuropathic pain

Oioid for moderate to severe ain

Adjuvant

pain ersisting or increasing

Oioid for mild to moderate ain

Non-oioid

Adjuvant

pain ersisting or increasing

Non-oioid

Non-oioid

Adjuvant

Cancer ain

Freedom from cancer ain

Ste 3

Ste 2

Ste 1

Fig. 3. WHO analgesic ladder.10

When patients are facingmultiple losses, as mostpalliative care patientsare, it is very important

for the patient to maintaincontrol of his/her pain

management for as long aspossible.

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Recommended rst-line treatment includescertain antidepressants (i.e. tricyclicantidepressants (CA)), through theiraction as sodium channel blockers; dualreuptake inhibitors o serotonin andnorepinephrine; calcium channel 2-ligands (i.e. gabapentin and pregabalin)and topical lidocaine. raditionally the

CAs have been the most common drugused in the public sector in South Aricaor treatment o neuropathic pain. Tey areinexpensive and placebo-controlled studieshave provided support or the ecacy oCAs in the treatment o neuropathic pain,especially in post-herpetic neuralgia andpainul diabetic peripheral neuropathy.16CA in randomised clinical trials havenot difered signicantly rom placebo inthe treatment o HIV neuropathy17 andneuropathic cancer pain,18 which are the twomost common conditions treated in SouthArican palliative care. CAs are cardiotoxic

and can cause sedation and have signicantanticholinergic efects.19 Regrettably thereis not enough research conducted on theuse o opioids in neuropathic pain despiteWHO guidelines that suggest an analgesicdrug in conjunction with an antidepressantor anticonvulsant or neuropathic pain inoncology patients.

Duloxetine is a selective serotonin norepine-phrine reuptake inhibitor SSNRI that hasshown signicantly greater pain relie inrandomised clinical trials compared withplacebo in patients with painul diabeticperipheral neuropathy.20 Its main side-efectsare nausea, sedation and dizziness.

Gabapentin and pregabalin are both calciumchannel 2- ligands which decrease therelease o glutamate, norepinephrine andsubstance P. Pregabalin and gabapentinhave shown ecacy in a wide varietyo neuropathic conditions and have noclinically important drug interactions,making them ideal drugs to use in thepalliative care setting. Unortunately, thesedrugs are dicult to obtain in the statesector and palliative care clinicians wouldlike to see these drugs as part o the essentialdrug list (EDL). Gabapentin and pregabalinrequire dosage reduction in patients withrenal impairment. It is also necessary to startat a lower dosage in the rail and elderly.

Studies have shown that lidocaine patch 5%improves pain in patients with post-herpeticneuralgia and allodynia,20 but these patchesare not available in South Arica. Lidocainegel was shown to be efective in pain reliein patients with post-herpetic neuralgia andallodynia22 but not in patients with HIVneuropathy.23

Opioid analgesics and tramadol arerecommended as third-line treatment in thetreatment o neuropathic pain in the generalpopulation. However, in neuropathic pain incancer, acute neuropathic pain, episodes oexacerbation o pain and while titrating up

medication these drugs are considered to berst-line medication. Opioid analgesics havedemonstrated efectiveness in reduction oneuropathic pain.24 Opioid analgesics arethe mainstay or the treatment o moderateto severe pain in palliative care. Whenadministered according to guidelines,opioids provide adequate pain relie ormore than three quarters o patients withcancer pain.25 Te main reason or notprescribing these drugs is still opiophobiaamong health proessionals.26 Mist morphine(liquid morphine) is cost efective, and side-efects (constipation, nausea, vomiting

and drowsiness) can easily be managed.Respiratory depression is rarely seen in thepalliative care setting where morphine isintroduced at low dose, administered orallyand titrated slowly to achieve pain relie.Research has also demonstrated that the risko addiction with the medical use o opioidsis low.

conlusionIt is always important to realise that anypain is not a homogenous entity andrequires reassessment and adjustment opain medication. Te pain a patient hastoday might not be the pain he experiencestomorrow because o the physical andphysiological changes patients in a palliativecare setting ace. Pain control is achievablein the Arican setting with good assessment,review and attention to detail.

aknowledgementDr Milton Raf or his input and guidance.

Referenes vilble t www.mej.org.z

Pain contr

IN A NUTSHELL

Pain in the palliative care setting can bcaused by the illness itsel, the treatmen(radiotherapy, chemotherapy, antiretro

viral treatment), concurrent disorder(tension headaches, urinary tract inec

tion) or by general debility. Physiologically the dierent types o

pain can be described as nociceptive (arthritis, cellulitis), visceral (pancreatitispeptic ulcers), neuropathic (herpes zoster, post-stroke pain) and mixed pain, combination o the other types o painound in certain disease states such aAIDS and cancer.

Because pain in palliative care is multidimensional, a multimodal approach ineeded to address both the physical andthe physiological actors.

Te most important element of a pain assessment in palliative care is to establisha good rapport with the patient and toshow empathy and understanding o hisher pain and sufering.

Once the clinician has a clear understanding o the type o pain, its severitypossible cause and emotional component o the pain, pharmacological andnon-pharmacological interventions canbe implemented.

Te World Health Organization has created a stepwise approach to the management o cancer pain known as the analgesic ladder.

Te International Association for thStudy o Pain (IASP) has developed newtreatment guidelines or the management o neuropathic pain guided by improved understanding o the physiology

o neuropathic pain and its managemen

In palliative care timebecomes a very importantfactor and combination

therapy may be needed forrapid onset of pain relief.

Te main reason for notprescribing these drugs is

still opiophobia amonghealth professionals.

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