- Medications should be given "by the ladder": This guideline suggests that practitioners should treat the reported level of pain, and escalate step-wise, if necessary. Step 1 is for the treatment of mild pain - NSAIDS are recommended. Step 2 is for mild to moderate pain, in which weak opioids, administered through the oral route, are indicated. Step 3 describes moderate to severe pain, in which administration of parenteral potent opioids should be considered. Finally, Step 4 is for intractable pain, in which invasive therapy, such as delivery of opioids by the epidural route should be used.
- Medications should be given "by the clock": This guideline reinforces the notion that pain medications should be administered on a scheduled basis rather than using PRN (pro re nata, or as needed) dosing. One of the most common causes of under-medication of children in pain is the use of PRN dosing, which can result in brief or inconsistent periods of pain relief, with increasing undesirable side effects. When pain medications are administered on a scheduled basis, a steady therapeutic level is achieved, providing consistent pain relief, and allowing for tolerance of side effects to develop.
- Medications should be given "by the mouth": This guideline is not to be taken literally (medications should not necessarily be given by mouth every time). Rather it is a reminder to always give medication through the least invasive route of administration available. For children, oral dosing with pain medications is preferred to any other route.
- Medications should be given "by the child": This guideline is a reminder to take into account the history and current needs of the individual child when determining proper doses of pain medications. Selection of an initial dose depends on the child’s prior exposure to pain medications, the severity of pain, their current hepatic or renal function, and the route of administration.
Pharmacologic interventions: These include NSAIDS, opioids (narcotic analgesics), adjuvant analgesics, and topical analgesics. NSAIDS include acetylsalicyclic acid (aspirin), ibuprofen (Motrin), acetaminophen (Tylenol), and naproxen (Naprosyn), among others. Use of aspirin is associated with Reye’s syndrome, a disease of the liver that can lead to fatal swelling of the brain in some cases. Thus, it is used sparingly in pediatric practice.
NSAIDS have analgesic, as well as anti-pyretic and anti-inflammatory effects (with the exception of acetaminophen). NSAIDS have a "ceiling effect," which means that once the maximum dose is given, additional drug will have no additional analgesic effect, although toxicities will continue to develop. This is an important and sometimes poorly understood feature of the NSAIDs. Many cases of severe liver toxicity are caused by an overdose with NSAIDs, given in a misguided attempt to treat severe pain. If pain persists after the maximum allowable dose of an NSAID is given, one should move up the WHO analgesic step-ladder and prescribe a weak opioid. Side effects of NSAIDS include decreased platelet aggregation, and gastric irritation, as well as a possibility for renal toxicity with long term use. Acetaminophen does not affect platelet function or irritate the stomach, but hepatic toxicity can occur with high doses of acetaminophen.
Opioid medications include codeine, morphine, fentanyl, and others. Opioids do not have a ceiling affect beyond that which is imposed by toxicity. There is an important drug interaction between zidovudine and morphine: in patients using morphine, hepatic metabolism and zidovudine excretion may be inhibited, resulting in toxicity of either or both drugs. Therefore, concurrent use is not recommended. Side effects of opioids include constipation, sedation, nausea & vomiting, and respiratory depression. Prevention of constipation is more effective than treatment once constipation occurs. Antiemetics should be used as needed to treat nausea and vomiting.
Respiratory depression is the most frequently cited concern of health care providers in administering pain medications, but it is a relatively rare occurrence. It is important to understand that cross-tolerance between opioid pain medications is incomplete. When switching from one opioid pain medication to another, the dose must be lowered; lowering it by half and then titrating from there is a rough guideline. When respiratory depression does occur, it is often due to an overdose of opioid pain medication caused by switching from one opioid medication to another without lowering the dose.
When using opioid pain medications, another frequently cited concern is the fear that children will become addicted. It is important to note that there is a distinction between tolerance, dependence, and addiction. Tolerance is a physiologic need for an increased dosage. Treatment of tolerance involves increasing opioid dose, switching to another opioid (and lowering the dose of the second opioid appropriately), adding adjuvants, or decreasing the duration between doses. Dependence is the physiologic withdrawal when drug is abruptly discontinued. Dependence is treated by tapering doses slowly over time. Addiction is a psychologic dependence on drugs. Addiction is extremely rare in children, and should not be considered a reason to withhold medications from a child in pain.
Adjuvant drugs are used in combination with NSAIDS or opioids to enhance pain management. Adjuvants can be divided into two categories: co-analgesic drugs, and drugs to treat side-effects. Co-analgesics include drugs from a variety of classes, including anti-convulsants, antidepressants, corticosteroids, sedatives, and others. Drugs used to treat side effects include antihistamines, psychostimulants, laxatives, antiemetics, and others.
Topical analgesics are used to prevent procedural pain. The most commonly used topical analgesic in Romania is EMLA cream (EMLA stands for eutectic mixture of local anesthetics). However, EMLA is expensive, and is still not widely used for children in Romania. Placed one hour in advance to the area where an intravenous line will be placed or a lumbar puncture is to be performed, the EMLA will reduce pain. EMLA cream does not address fear of shots. Often children will still cry due to fear and anxiety.
Non-pharmacologic interventions: These can be divided into two categories: peripheral techniques, which treat pain of specific body parts, and central techniques, which relax the whole body. It is important to emphasize that non-pharmacologic pain interventions are an adjunct and never a substitute for appropriate medications. Successful use of non-pharmacologic pain interventions is dependent on a therapeutic caregiver-patient relationship, and an understanding of the mechanism of action of the interventions and the mind-body connection. Before discussing specific non-pharmacologic interventions, it is important to consider their theoretical mechanism of action: what is known as the Gate Control Theory (GCT) of pain.
According to the GCT, a sensory message, sent via a stimulated nerve signal, travels to the spinal cord. There the message is processed and sent through a "gate" to the thalamus. It is in the thalamus that pain is perceived, synchronized, and transmitted to the cerebral cortex. The "gate" is then open or closed, depending on the patient’s current emotional state, their interpretation of the situation, and the amount of attention given to the painful stimulus. A past painful experience may stimulate a nervous system response, and result in muscle tension, rapid heart rate, increased respiration rate and feelings of helplessness or loss of control. Recollection of that experience or anticipation of a second painful experience can produce the same psychologic feelings and physiologic responses, even before the episode occurs.
Peripheral techniques for pain control usually include cutaneous stimulation, such as massage, heat application, cold application, and immobilization. Massage theoretically stimulates the large nerve fibers of the skin to close the "gate" and block transmission of pain messages to the thalamus. Heat application has been used for centuries, and is used effectively for muscle and joint pain, and muscle relaxation. Cold application is useful in initial post-trauma conditions to reduce bleeding, swelling, and pain. Cold is also particularly effective for dental pain. Immobilization can be employed to manage acute injuries related to bone fractures or limb or joint disturbances. Swaddling of infants is another form of immobilization that is comforting and soothing to young infants.
Central techniques for pain control include exercise, cognitive interventions, and behavioral interventions. Exercise enables children to maintain some level of activity by mobilizing joints, stretching muscles, and restoring coordination and balance.
Cognitive interventions assist children in coping with anxiety and discomfort, and include health education, relaxation, and distraction. It is important to inform the child and family of exactly what will happen during each visit to the clinic or hospital. For children with HIV/AIDS, clear and appropriate education about the disease eliminates a considerable amount of confusion, and creates some predictability and feelings of control.
Relaxation techniques include imagery, deep-breathing, meditation, and music-assisted relaxation. Prayer is sometimes used as a coping strategy by children who have religious beliefs. Prayer may be silent or verbal, directed or non-directed, and is useful as a focusing technique. Distraction enables children to cope during painful situations by shifting their attention and concentration from painful foci. Multiple sensory distraction involves many senses concurrently. For example, patients may listen to music while focusing on a flower or plant, while they are holding, touching, or rubbing something, or nodding to the rhythm of music.
Effective behavioral interventions vary among children, and depend on the child’s developmental level, particular interests, and abilities. Bubble-blowing has been reported to be remarkably successful for young and developmentally delayed children. Other behavioral techniques include play therapy, exercise, and others. All of these peripheral, cognitive, and behavioral non-pharmacologic techniques can be carried out in resource-poor settings if they are practiced and tailored to the individual needs of each child.
