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64 Pain Management

If analgesic requirements are still not met, then codeine, a mild catheter placed into the epidural space. Epidurals are especially useful
opiate, should be administered. This is generally considered a safe in thoracic procedures and after laparotomy. They are usually inserted
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drug with a significantly lower incidence of respiratory depression than in the anaesthetic room and can be linked to a PCA system (where
other stronger opioids. Nausea and constipation are relatively common they become patient-controlled epidural analgesia, or PCEA, systems).
side effects that should be anticipated wherever codeine is prescribed. Their main advantage is that the analgesic action of opioids can be
Codeine phosphate is most commonly given by mouth, although rectal gained without the systemic side effects. However, there are numerous
preparations are available. disadvantages to the system. The incidence of postoperative urine
In patients whose pain is still not adequately controlled, or those retention is reasonably high, so catheterisation is often recommended;
who are deemed to have severe pain at initial assessment, a strong epidurals should be avoided in patients at high risk of bleeding or
opioid should be used. The “lower steps” of the analgesic ladder infection; and there is a risk of inappropriate level of blockage, so
(see Figure 11.3) should always be prescribed as well, with the sensory level should be routinely checked while an epidural is in place.
exception of codeine. Morphine may be administered in oral solution, Ketamine merits special mention with regard to pain control in areas
intramuscularly, or intravenously, depending on clinical need. An where access to and training in administering other modes of analgesia
intranasal preparation is also now available and is especially useful are limited. This anaesthetic drug has also been shown to have good
in the emergency management of acute pain where intravenous analgesic properties at subanaesthetic dosages. It can be administered
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access is not always available. Patient-controlled analgesia (PCA) intravenously (IV) or by IM injection, and is generally well tolerated in
is an alternative mode of administration of intravenous morphine paediatric patients. Its main adverse effects are transient hypertension,
administration by which the patient can choose when doses are given vomiting, agitation on recovery, and hallucinations. Diazepam is
according to need. PCA has been found to produce the same analgesic coprescribed to buffer the duration and intensity of any side effects.
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effect as intramuscular (IM) regimes, but with less sedation. Prevention
Morphine has multiple side effects that should be anticipated
whenever it is prescribed. Nausea and vomiting are commonplace, so Although it is difficult in practice to completely prevent pain in hospi-
antiemetics should be routinely prescribed on an “as required” basis. talised children, several strategies can help to minimise it. Naturally, the
Urine retention is a recognised complication, especially in postoperative accurate diagnosis and prompt treatment of the underlying condition
patients, so many centres routinely catheterise patients until their opiate before pain escalates is highly desirable. Regular prescription of anal-
requirement has ceased. Respiratory depression is the most feared gesia is more effective than medicine given only when pain arises. The
complication associated with the use of morphine. Regular, documented clinician should also attempt to recognise the potential for procedures
monitoring of sedation level and respiratory parameters should be to be painful or distressing and carefully consider which measures
mandatory, as should the coprescription of “as required” naloxone are really necessary so that only those that are likely to bring about a
wherever opioids are prescribed. Concern about respiratory compromise change in management are undertaken.
should not, however, influence the decision to use morphine in those When potentially painful procedures are required, a range of
who need it. Parents and health care professionals alike should be methods can be employed to prevent unnecessary pain. This includes
reassured that dependence is rare in children with surgical pain. administration of analgesics before an event as well as the use of
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Opioid use in Africa is rare; possible reasons include strict national special additional measures, such as Entonox in dressing changes
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laws against opioid addiction and misuse of drugs, lack of knowledge, of burn patients, or local anaesthetic creams (EMLA —a eutectic
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and nonavailability, as reported by WHO. For example, morphine mixture of local anaesthetics—or Amitop ) and cold sprays to minimise
consumption in South Africa for 2004 was 4.6682 mg per capita in discomfort associated with phlebotomy or removal of foreign objects.
comparison to Uganda’s 0.4001 mg per capita, Tanzania’s 0.3250 mg In the longer term, minimising pain for paediatric patients will
per capita, and Zambia’s 0.0704 mg per capita, and the use of pethidine require continued efforts to educate and train staff in its assessment and
in Uganda for 2004 was 0.2272 mg per capita, in contrast to South management. Crucially, this should involve dispelling such commonly
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Africa’s 3.7694 mg per capita. held myths as that infants do not feel pain and the active child is not in
pain, and the general feeling that children have to “earn” analgesics
Additional Methods of Analgesia before they are given.
Certain additional techniques are frequently employed in the periop-
erative period to improve pain management, as described here. Local Ethical Issues
anaesthetics can be used to create specific nerve blocks to reduce The African child is particularly vulnerable to disease and injury, and
postoperative pain sensation from specific sites. The duration of such subsequently to pain and suffering. Factors such as inadequate training,
blocks depends upon the specific anaesthetic used, but is typically language barriers, cultural diversity, limited resources, and the burden
around 6–8 hours. Local anaesthetics now exist in a variety of formats, of disease prevent sick and injured children from receiving basic pain
including gels and creams that can be applied postoperatively as well care. This situation can be rectified only by providing pre- and post-
as solutions that can be infiltrated into operative sites. Local applica- graduate training on the safe use of analgesic preparations, making
tion of anaesthetic creams is particularly useful in procedures involving drugs available, and gaining government support.
the skin or mucous membranes, and has been shown to be effective in These ethical issues are best summarised in a review titled:
reducing wound pain in the postoperative period. An advantage of this “Challenges associated with paediatric pain management in Sub Saharan
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is that community medical officers can easily acquire and utilise this Africa” in the International Journal of Surgery. 1
technique to reduce pain associated with procedures. Evidence-Based Research
When a greater area of analgesic coverage is required, an epidural
may be used. This form of regional anaesthesia involves injection of Table 11.1 deals with a study of postoperative pain relief following
analgesics (usually local anaesthetic with or without opioids) through a inguinal herniotomy.