Morphine postoperative

There was a higher incidence of adverse effects of morphine in patients with renal insufficiency who receive opioids for some time (37), and in patients with hemolytic uremic syndrome who were given ketamine with subcutaneous morphine postoperatively (38). 

This type of pain management is used for postoperative pain, labor pain, and cancer pain. The most serious adverse reaction associated with the administration of narcotics by the epidural route is respiratory depression. The patient may also experience sedation, confusion, nausea, pruritus, or urinary retention. Fentanyl is increasingly used as an alternative to morphine sulfate because patients experience fewer adverse reactions. 

Cross A, Asher L, Seguin M, Yuan L, Kelly N, Hammack C (1995) The importance of a hpopoly-sacchaiide-initiated, cytokine-mediated host defense mechanism in mice against extraintesti-nally invasive escheiichia coh. J Clin Invest 96(2) 676-686 Dahan A, van Dorp E, Smith T, Yassen A (2008) Morphine-6-glucuronide (M6G) for postoperative pain relief. Eur J Pain 12(4) 403-411... 

Opioids maybe administered in a variety of routes including oral (tablet and liquid), sublingual, rectal, transdermal, transmucosal, intravenous, subcutaneous, and intraspinal. While the oral and transdermal routes are most common, the method of administration is based on patient needs (severity of pain) and characteristics (swallowing difficulty and preference). Oral opioids have an onset of effect of 45 minutes, so intravenous or subcutaneous administration maybe preferred if more rapid relief is desired. Intramuscular injections are not recommended because of pain at the injection site and wide fluctuations in drug absorption and peak plasma concentrations achieved. More invasive routes of administration such as PCA and intraspinal (epidural and intrathecal) are primarily used postoperatively, but may also be used in refractory chronic pain situations. PCA delivers a self-administered dose via an infusion pump with a preprogrammed dose, minimum dosing interval, and maximum hourly dose. Morphine, fentanyl, and hydromorphone are commonly administered via PCA pumps by the intravenous route, but less frequently by the subcutaneous or epidural route. 

G. Gourlay and R. Boas, Fatal outcome with use of rectal morphine for postoperative pain control in an infant, Br. Med. J, 304, 766 (1992). 

Dahan A, van Dorp E, Smith T, Yassen A. (2008) Morphine-6-glucuronide (M6G) for postoperative pain relief. Eur J Pain 12 403 11. 

Nalorphine and levallorphan are examples. For example in patients with postoperative pain the analgesic effects of 10 mg of nalorphine is about the same as 10 mg of morphine. On the other hand naloxone and naltrexone seem to have no agonistic activity and some antagonistic affinity for all types of opioid receptors. Although antagonists could be expected to have effects by altering the actions of endogenous opioid peptides mostly such effects are not discernable. 

Ketorolac (Toradol) is an NS AID with very mild antiinflammatory and antipyretic activity. It is a potent analgesic for postoperative pain. Its efficacy is equivalent to that of low doses of morphine in the control of pain. For this reason it is often combined with opioids to reduce opioid dose and related side effects while providing adequate pain relief. It is also used to replace the opioids in some patients with opioid sensitivity. The mechanism of action of ketorolac involves the inhibition of COX and decreased formation of prostaglandins. However, some evidence exists that ketorolac may stimulate the release of endogenous opioids as a part of its analgesic activity. 

Levorphanol (Levo-Dromoran) is an L-isomer morphi-nan derivative of morphine that is five to seven times more potent than morphine. It produces all of the side effects associated with morphine but less nausea. It is indicated for moderate to severe pain as a preoperative anxiolytic. It is often used in combination with thiopental to reduce the latter drug s anesthetic dose and to decrease postoperative recovery time. The o-isomer of levorphanol, dextrorphan, does not possess opioid analgesic activity but is a useful antitussive. 

These are the most commonly used drugs. Morphine (10-15 mg IM), pethidine (50-100 mg IM) are frequently used drugs for their sedative and analgesic property. They reduce the anxiety and apprehension, produce pre- and postoperative analgesia, help in smooth induction. They also reduce... 

Dosages and routes of administration Morphine is available in different salt forms but the hydrochloride and sulfate (Vermeire and Remon, 1999) are used preferentially. The compound can be administered by the oral, parenteral or intraspinal route. Oral application is preferred for chronic pain treatment and various slow release forms have been developed to reduce the administration frequency to 2-3 times per day (Bourke et al., 2000). Parenteral morphine is used in intravenous or intramuscular doses of 10 mg, mostly for postoperative pain and self-administration devices are available for patient-controlled analgesia (PCA). Morphine is additionally used for intraspinal (epidural or intrathecal) administration. Morphine is absorbed reasonably well in the lower gastrointestinal tract and can be given as suppositories. 

Side-effects Morphine induces a variety of centrally- and peripherally-mediated side-effects. The most important of which is respiratory depression following parenteral administration, especially in the postoperative situation. Chronic oral application induces constipation and chronic treatment with oral morphine must be supplemented with laxatives. Other frequent side-effects are nausea, vomiting, dizziness and sedation. 

Analgesic efficacy and clinical use Piritramide (Gibb and Pikler, 1973 Kumar and Rowbotham, 1999) is used for the treatment of acute, preferentially postoperative pain (Lehmann et al., 1986) and as an adjunct to anesthesia. It is less potent than morphine. 

Bourke, M., Hayes, A., Doyle, M., McCarroll, M.A. Comparison of regularly administered sustained release oral morphine with intramuscular morphine for control of postoperative pain, Anesth. Analg. 2000, 90, 427-430. 

Ohqvist, G., Hallin, R., Gelinder, S., Lang, H., Samuelson, S. A comparison between morphine, meperidine and ketobemidone in continuous intravenous infusion for postoperative relief, Acta Anaesthesiol. Scand. 1991, 35, 44-48. 

Motsch, J., Graber, E., Ludwig, K. Addition ofclonidine enhances postoperative pain analgesia from epidural morphine a double blind study, Anesthesiology 1990, 73, 1067-1073. 

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. 

Pereira et al. (1993) evaluated postoperative pain relief and incidence of side-effects of the combination of epidural morphine (0.5 mg) and sublingual nifedipine (10 mg). In this double-blind, placebo-controlled study 36 women were submitted to elective operations (hysterectomy and colpoperineoplasty). The nifedipine-treated group showed a significant drop in blood pressure which was controlled by rehydration. The results indicate that epidural morphine-induced postoperative pain relief may be enhanced by systemic administration of nifedipine with easily controlled side-effects. 

Oxycodone is a semisynthetic opioid derived from thebaine and used for oral pain relief. It is commonly formulated as an immediate-re lease medication with acetaminophen or aspirin. A con-trolled-release oxycodone formulation is used for the treatment of moderate to severe pain it provides controlled drug delivery over 12 h. The oral bioavailability of this formulation is 60 to 87%.35 The results of clinical studies of patients with postoperative and cancer pain show that oxycodone has a potency 1.5 times that of morphine. 

Bellissant E, Estebe JP, Sebille V, Ecoffey C. Effect of preoperative oral sustained-release morphine sulfate on postoperative morphine requirements in elective spine surgery. Fundam Clin Pharmacol. 2004 18 709-714. 

Viscusi ER, Reynolds L, Chung F, et al. Patient-controlled transdermal fentanyl hydrochloride vs intravenous morphine pump for postoperative pain a randomized controlled trial. JAMA. 2004 291 1333-1341. 

Cepeda MS, Alvarez H, Morales O, Carr DB. Addition of ultralow dose naloxone to postoperative morphine PCA unchanged analgesia and opioid requirement but decreased incidence of opioid side effects. Pain. 2004 107 41-46. 

Sveticic G, Eichenberger U, Curatolo M. Safety of mixture of morphine with ketamine for postoperative patient-controlled analgesia an audit with 1026 patients. Acta Anaesthesiol Scand. 2005 49 870-875. 

Morphine has a strong analgesic effect and has been used for the alleviation of postoperative and cancer pain since antiquity, but its use is now restricted because of its drug dependency. Morphine and its homologues were called opiates after opium, which was extracted from poppy seeds. This class of drugs are now termed opioids. 

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