| Local anesthetics | These agents may be administered by local infiltration or topical application. For topical use, a eutectic mixture of local anesthetics (EMLA) is efficacious in use with procedures and is now available in the United States (Kapelushnik, Koren, Solh, et al., 1990). When EMLA is used as a local anesthetic, it should be applied 60 to 90 minutes before the procedure. |
|---|---|
| Opioids | These drugs can be given via the intravenous or oral route. The intravenous route has the advantage of rapid effect and ease of titration. Intravenous opioids can be given in increments (e.g., 0.03 to 0.05 mg per kg of morphine every 5 minutes for children and other patients who weigh less than 50 kg, or 2 to 4 mg of morphine every 5 minutes for adults and children who weigh more than 50 kg) and titrated to analgesic effect (Schechter, Weisman, Rosenblum, et al., 1990). Oral opioids can be used when close and rapid titration to effect is not required. Other opioids may be used instead of morphine. Meperidine is suitable for brief, titrated dosing but not for prolonged use. Intravenous fentanyl may be used in small doses (25-micro-g increments, or 0.5 micro-g/kg for patients who weigh 50 kg or less). If given slowly in increments, the risk of chest wall rigidity is extremely small, but if it occurs, it should be managed immediately by the administration of a rapid-onset muscle relaxant and supporting ventilation. Transdermal fentanyl is not recommended for this indication because it requires on average 14 hours to reach peak application after administration (Varvel, Shafer, Hwang, et al., 1989). |
| Benzodiazepines | These agents can be given orally, intravenously, or transmucosally and provide anxiolysis, skeletal muscle relaxation, and in higher doses, amnesia. After opioids, intravenous benzodiazepines are given in increments and titrated to sedative effect (Sievers, Yee, Foley, et al., 1991; Zeltzer, Altman, Cohen, et al., 1990). Unlike diazepam, midazolam does not cause pain and local sclerosis when given intravenously (Zeltzer, Altman, Cohen, et al., 1990). For adults, midazolam is traditionally titrated in increments of about 0.5 mg. Benzodiazepines provide sedation, not analgesia, and hence, they often are used with opioids for painful procedures. If the combination of opioid plus benzodiazepine is used, the risk of respiratory depression is increased significantly, and careful titration and monitoring are required, particularly in the elderly. |
| Barbiturates | These drugs provide excellent sedation. They have no analgesic effects and are used with analgesics for painful procedures. Some patients may have paradoxical reactions, and for most patients, the sedation persists for many hours after the procedure is completed (Zeltzer, Jay, and Fisher, 1989). As with benzodiazepines, close observation for respiratory depression is essential, particularly when the intravenous route is used or if an opioid is coadministered. |
Intraventricular
Management of Side Effects
General comments and cautions regarding the use of opioid analgesics
Adjuvant analgesic drugs for cancer pain
Drugs and routes of administration not recommended for treatment of cancer pain
Pharmacologic Strategies for Procedural Pain
Sedation for Procedural Pain
Analgesics for Neonates and Young Infants
Index