Opioid in children

Knowledge of the use of spinal opioids in children is limited, but adverse effects are similar to those reported in adults (SEDA-18, 85) (130-132). Dysphoria has also been reported, but attributed to systemic absorption (132). 

Tyler DC, Krane EJ. Epidural opioids in children. J Pediatr Surg 1989 24(5) 469-73. 

Children may have a faster rate of clearance of oxycodone than adults, and ventilatory depression may be greater than with comparable opioids in children (SEDA-19, 85). 

Depressant effects on the CNS are the most profound. Nausea, vomiting, and miosis may develop within Ih. Infants and children may demonstrate unusual sensitivity while habituated adults may have extreme tolerance to opioids. In children, greater... 

Dextromethorphan is an opioid antitussive similar in action to codeine and pholcodine. Codeine and pholcodine are considered to be more potent than dextromethorphan. Dextromethorphan tends to cause less constipation and dependence than codeine. Cough suppressants are not usually recommended in children under 2 years. 

Diphenoxylate (marketed in combination with atropine as Lomotil in the United States) is chemically related to both analgesic and anticholinergic compounds. It is as effective in the treatment of diarrhea as the opium derivatives, and at the doses usually employed, it has a low incidence of central opioid actions. Diphenoxylate is rapidly metabolized by ester hydrolysis to the biologically active metabolite difenoxylic acid. Lomotil is recommended as adjunctive therapy in the management of diarrhea. It is contraindicated in children under 2 years old and in patients with obstructive jaundice. Adverse reactions often caused by the atropine in the preparation include anorexia, nausea, pruritus, dizziness, and numbness of the extremities. 

Opioid antagonists have been used with mixed results in adults with PTSD. No clinical trials with these agents have been published in children and adolescents with PTSD. The opioid antagonists such as naltrexone may have limited utility in treating debilitating self-mutilative behavior and perhaps in reducing substance abuse comorbidity in adolescent patients with PTSD. 

The opioid derivatives most commonly used as antitussives are dextromethorphan, codeine, levopropoxyphene, and noscapine (levopropoxyphene and noscapine are not available in the USA). They should be used with caution in patients taking monoamine oxidase inhibitors (see Table 31-5). Antitussive preparations usually also contain expectorants to thin and liquefy respiratory secretions. Importantly, due to increasing reports of death in young children taking dextromethorphan in formulations of over-the-counter "cold/cough" medications, its use in children less than 6 years of age has been banned by the FDA. Moreover, due to variations in the metabolism of codeine, its use for any purpose in young children is being reconsidered. 

Clinical use The indications for levobupivacaine include wound infiltration (0.25 % solution), nerve conduction block (0.25 - 0.5 %), spinal analgesia (0.5 %) and epidural anesthesia (0.5 to 0.75 %). For labour analgesia, lower concentrations of levobupivacaine are recommended when administered as epidural injection (0.125 to 0.25 % up to 25 mg) or infusion (0.25 %). The maximum dose for ilioinguinal or iliohypogastric block in children is 1.25 mg/kg/side (0.25 to 0.5 % solutions). For postoperative pain management, levobupivacaine can be applied epidurally in combination with the opioids fentanyl or morphine or with the a2-agonist clonidine. 

Maxwell LG, Kaufmann SC, Bitzer S, et al. The effects of a small-dose naloxone infusion on opioid-induced side effects and analgesia in children and adolescents treated with intravenous patient-controlled analgesia a double-blind, prospective, randomized, controlled study. Anesth Analg. 2005 100 953-958. 

Codeine Phosphate The presence of aspirin along with codeine, even at a low moisture level, leads to acetylation of codeine phosphate in solid dose forms and is incompatible.36 Codeine sulfate solutions are more stable than phosphate salts.37 Drug dependence and withdrawal resemble that of opioid analgesics. Overdose causes acute intoxication in children, as accidental or deliberate ingestion of cough preparations containing codeine.38... 

The nonsalicylate NSAIDs are especially useful for pain of inflammatory origin.These analgesics are relatively safe, are well tolerated, have few serious side effects, can decrease or even eliminate the need fc>r opioids, and are nonaddictive. NSAIDs that have been used effectively and are approved for use in children include ibuprofen, naproxen, and tolmetin. Because all these drugs can cause gastritis, they should be taken with meals. If GI side effects persist with one NSAID, an alternative agent should be selected. 

Stool softeners and cathartics can be used in children, as in adults, to relieve symptoms of constipation. Nausea and vomiting generally diminish as opioid therapy is continued, but antihistamines with antiemetic effects, such as hydroxyzine or promethazine, may be helpful as adjuvants to diminish impleasant G1 symptoms. Reducing the opioid dose to minimal analgesic levels may help to limit sedation or drowsiness. Mild respiratory depression, an uncommon side effect in children, may require only that the opioid dose be reduced. 

Movement disorders after withdrawal of continuous infusion, without the characteristic autonomic signs of opioid withdrawal, have been reported in children (SEDA-17,80). Fentanyl-induced seizures have been reported (10). Life-threatening complications have included raised intracranial pressure and critically reducing cerebral perfusion (11). 

Midazolam was used in a wide range of doses (0.03-0.6 mg/kg) in 91 children undergoing diagnostic or minor operative procedures with intravenous midazolam sedation (7). Opioids were co-administered in 84% and oxygen desaturation occurred in 32%, most of whom had received high doses of opioids in addition to the midazolam. Other adverse events included airway obstruction (n = 3) and vomiting (n = 1). The presence of independent appropriate trained personnel not directly involved in performing the procedure, appropriate resuscitation... 

Convulsions occurred in a baby born to an opioid-dependent mother. This case is unusual, as convulsions due to neonatal opioid withdrawal do not usually occur in the first 24 hours after delivery it suggests that naloxone should be used with great caution in children born to opioid-dependent mothers (13). 

The use of opioids in very young patients is increasing. In a review of pain management in children, various routes of administration of opioids and their associated adverse effects have been discussed (SEDA-17, 78). Attention has been drawn to the adverse effects of intravenous codeine in children and to the risk of convulsions with pethidine in neonates, because of accumulation of its metabolite norpethidine. The risk of respiratory depression with morphine was also highlighted, and morphine is recommended for use only in neonates who are being ventilated or intensively nursed. Routine use of pulse oximetry has been recommended in all children receiving opioids (SEDA-21, 86). 

Acute opioid poisoning involves marked CNS depression, with drowsiness, loss of consciousness, and coma. Other prominent features are a reduced respiratory rate, hypotension, and sjmmetrical pinpoint pupils (unless the patient has been hjrpoxic for some time, in which case the pupils can be dilated). Reduced urine output, hypothermia, flaccid skeletal muscles, and pulmonary edema can also be present. Convulsions have occurred in children. 

Diphenoxylate is a narcotic-like substance that slows gastrointestinal motility and depresses the central nervous system producing coma and respiratory depression. Anticholinergic effects (secondary to the presence of atropine as an abuse deterrent) can be seen early after exposure with opioid effects occurring later. There is no correlation between the dose ingested and the severity of effects in children. Severe poisonings with coma and respiratory depression have been reported in children with small ingestions. 

The Cochrane Library is a relatively new and growing electronic library that provides more than 850 summaries of published literature about pharmaceutical and other interventions to improve health. The Library adds new titles four times a year to its cumulative online and CD versions (the latter, available by subscription, offers more databases). The Library s 2000 Issue 3 contains evidence on dozens of clinical dilemmas, such as antibiotic treatment for traveler s diarrhea, antileukotriene agents compared to inhaled corticosteroids in the management of recurrent and/or chronic asthma, opioid antagonists for alcohol dependence, and bromocriptine versus levodopa in early Parkinson s disease. The Cochrane Library also updates earlier reviews when important new evidence becomes available. Among the newest updates are tacrine for Alzheimer s disease, tricyclic and related drugs for nocturnal enuresis in children, and nicotine replacement therapy for smoking cessation. 

Opioids remain the mainstay of pain treatment. Useful guidelines for their administration have been developed for a number of clinical situations, including treatment of acute pain, trauma, cancer, nonmalignant chronic pain, and pain in children. In the case of cancer pain, adherence to standardized protocols can improve pain management significantly. Guidelines for the oral and parenteral dosing of opioids are presented in Table 21-5. 

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