256 Archives ofDisease in Childhood 1993; 69: 256-259 PERSONAL PRACTICE Arch Dis Child: first published as 10.1136/adc.69.2.256 on 1 August 1993. Downloaded from Practical management of pain in sickling disorders Richard Grundy, Richard Howard, Jane Evans Sickle cell disease affects approximately 5000 This is best achieved within the context of a people in the UK predominantly of African multidisciplinary team approach. and Afro-Caribbean origin.1 The majority of those affected live in inner city areas; for example it is the most common inherited Pathophysiology condition in the City and Hackney district of Sickle cell related pain is thought to be due to London. There is a high morbidity and vaso-occlusion. The unstable haemoglobin of mortality in children with up to 10% dying sickling disorders polymerises when deoxy- within the first 10 years of life.2 Sickle cell genated to form the classical inflexible sickle related pain is the most frequent problem shaped cells, these slow capillary blood flow experienced by young patients.1 3 4 In a care- causing local hypoxaemia and further sick- fully documented home study of children ling.4 Acceleration of this process may with homozygous sickle cell disease the occlude collateral flow resulting in ischaemia, number of painful crises averaged 3-9 per infarction, and tissue necrosis.15 A recent patient per year, not all requiring hospital alternative hypothesis is that painful crises admission but severe enough to undermine may be initiated by a centrally mediated reflex normal activities.5 The disease varies in shunting blood away from the bone marrow severity depending in part on the genetic resulting in avascular necrosis.16 Precipitat- abnormality inherited; those homozygous for ing factors are legion, examples include infec- the classical sickle mutation tend to have the tion, dehydration, exposure to cold, stress, greatest frequency of painful episodes fol- and tiredness although many episodes are lowed by sickle ,' thalassaemia, haemoglobin unexplained.34 7 17 The mechanisms under- SC disease, and sickle PI thalassaemia.6 lying the clinical variability of sickling http://adc.bmj.com/ However within each genotype the number of diseases is ill understood but involves the painful episodes experienced per year varies interaction of genotype, haematological widely.6 A recent large study found that indices, rheological, endothelial, and micro- approximately 25% of those with homozy- vascular factors.4 gous sickle cell anaemia have severe disease The widely held belief that the fetus and with three to 10 admissions per year, 50% neonate do not experience pain has been have at least one severe episode per year, and refuted by evidence documenting the consider- on September 29, 2021 by guest. Protected copyright. the remainder rarely present with sickle cell able and deleterious physiological, hormonal, related pain.6 7 The inpatient stay is usually and metabolic changes induced by pain and between 5-10 days in hospital, but may be stress. These effects can be ameliorated by longer making this complication a consider- adequate analgesia.18 19 It is that able possible source of morbidity and consumer of similar adverse physiological effects may occur resources.6-8 in sickle cell related pain further complicated Sickle cell related pain occurs as an acute by the emotional associations of this sensation. circumscribed event within the context of a This hypothesis supports the argument for chronic illness presenting a clinical challenge adequate analgesia during a painful episode whose management is controversial.9 10 but clearly further research is required. There is substantial evidence that pain is undertreated in children, not least in those with sickling disorders.11-3 This may occur Natural history due to fear of inducing addiction or a failure The ability of a child to express pain is affected to understand the importance of treating pain by racial and cultural factors and past experi- in children and is hindered by the complexity ences. Some appreciation of the nature and Queen Elizabeth's of assessing its severity.11-13 Pain in children severity ofpainful episodes may be gained from Hospital For Children, should be judiciously and competently African tribal names for sickle cell disease, Hackney Road, treated in order to minimise London E2 9PS immediate 'hemkom' (Adangme tribe) meaning body Richard Grundy complications and allow normal emotional biting and 'nuidudui' (Ewe tribe) body Richard Howard and physical development.'4 The increased chewing.20 The onomatopoeia of 'nuidudui' Jane Evans life expectancy for those with sickling disor- and 'chwechweechwe' (Ga tribe) reflecting the Correspondence to: ders means that the long term consequences relentless and repetitive gnawing pains in Dr Richard Grundy, of treating sickle cell related pain in children Oncology Group, Institute of bones and joints.20 Pain arising from a serious Child Health, 30 Guilford needs to be carefully considered in terms of injury or postoperatively is often considered Street, London WC1N 1EH. development, function, and quality of life. less severe than sickle related pain. Practical management of pain in sickling disorders 257 Strategiesfor coping with pain Analgesia Milder painful crises can often be managed at (1) Age 6 months-4 years Arch Dis Child: first published as 10.1136/adc.69.2.256 on 1 August 1993. Downloaded from i. Parental education home with rest, warmth, hydration, and oral ii. Encourage home management where and when analgesics. Regular administration of paraceta- possible iii. Nurse controlled analgesia for severe pain mol (12 mg/kg every four to six hours), non- (2) Age 4-7 years steroidal anti-inflamatory drugs such as i. Introduce patient and continue parent education or ii. Teach pain coping skills ibuprofen 5 mg/lkg every six hours, codeine iii. Introduce PCA when well, that is in clinic phosphate 1 mg/kg every four to six hours, may iv. Continue to encourage and support home care crises. (3) Age 8-16 years contain such i. Continue the above basis tenets of care and Children whose pain cannot be managed at education ii. Support patient and family home present to the accident and emergency iii. Liaise with school and provide educational department of their local hospital. It is impor- information tant to give priority to such patients and aim to ease their pain within 30 minutes of admission. Sickle cell related pain predominantly affects Delay in being seen is a source of frustration the younger population.4 The painful crisis is and anger at a difficult time for the child and unpredictable. It varies in timing, duration, the parent.22 Where possible the child should location, and intensity both between and be seen by a member of the haematology team within each episode.47 21 The episode ends thus providing reassurance and continuity of with a return to the status quo. A prodromal care. When pain is severe an opioid should be period often occurs that either leads to severe prescribed. Traditionally pethidine has been pain or grumbles on for a few days before used, however, accumulation of the metabolite receding; conversely severe pain may start norpethidine has been reported to cause con- abruptly.22 Children tend to present with limb vulsions suggesting that this drug should be pain, the swollen painful joints of dactylitis avoided in patients with sickle cell disease.8 being a classic clinical finding, older patients Morphine is suitable and initially may be given present with juxta articular pain from larger orally; if this route is inappropriate or too slow joints.3 A rigid abdomen indistinguishable then it is best given either intravenously from that seen in acute surgical conditions is or subcutaneously. There is little indication not uncommon in the older child.23 It usually for intramuscular administration.26 Concerns coexists with pain elsewhere, bowel sounds are about drug induced respiratory depression often normal, and vomiting rare; careful and leading to an acute chest syndrome or of drug regular assessment by surgeon and paediatri- dependence are not supported in the literature cian is necessary. or in practice provided management is appropriate.'0 27 28 Pain arising from rib infarc- tion, infection, overhydration, or pulmonary Management intravascular sickling are more likely to lead to All children presenting with an acute painful this complication.29-31 http://adc.bmj.com/ episode need careful evaluation looking for Postoperative studies have demonstrated other complications of sickle cell disease.3 that analgesia is often inadequately given and General medical management includes keep- acceptable pain relief rarely obtained.32 ing the child warm, rested, and ensuring Furthermore many children will not actively adequate hydration; the latter is usually given seek treatment for pain. In sickle cell related intravenously (80-100 mil/kg/day). Fever and a pain the opioid dose required to achieve pain raised white cell count are common findings, relief varies considerably within each painful on September 29, 2021 by guest. Protected copyright. and although they are more likely to be due to episode, from one episode to another and vaso-occlusion broad spectrum antibiotics between individual patients.2' Continuous should be given until blood cultures are known infusions of opioid have improved this to be negative. Oxygen is indicated only if situation, being effective and widely there is evidence of hypoxaemia as inappropri- used.8 21 28 The recent introduction of patient ate use may down regulate erythropoietin controlled analgesia (PCA) in clinical practice production.24 There is little evidence that provides several advantages for sickle cell blood transfusion influences the course of the related pain. The patient can administer a pre- crisis unless complicated by the girdle syn- defined bolus of analgesia at the time of an drome or sickle chest disease. A transfusion exacerbation of the pain or when the analgesic programme may be appropriate for those with effect is wearing off.