الفهرس 
Pathophysiology of addictionOnly 14 pages are availabe for public view
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Abstract
A
ddiction is a chronically relapsing disorder characterized by compulsion to seek and take drug(s) regardless of the adverse consequences that may ensue
An opioid is any natural or synthetic compound, which has morphine-like properties
Opioid receptors are a group of G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin.Opiate receptors are distributed widely in the brain, and are found in the spinal cord and digestive tract
OPIOID AGONISTS
The most widely used opioid analgesics are the pure agonists, and all of these are relatively selective for µ opioid receptors.
OPIOID ANTAGONISTS
Acts as competitive antagonist at all opioid receptors, but it has greatest affinity for µ receptors. Small doses of naloxone reliably reverse or prevent the effects of pure opioid agonists and most mixed agonist–antagonists. The block is reversible and competitive, so it can be overcome by additional agonist
OPIOID AGONIST–ANTAGONISTS
The agonist–antagonist opioids are synthetic and semisynthetic analgesics that are structurally related to morphine. All these compounds produce some degree of competitive antagonism to morphine and the other pure agonists
Anesthesia providers have a greater risk for becoming addicted than other physicians because they have ready access to drugs that they personally can either administer to patients or divert for their own abuse.
Chronic hypoxemia and reactive pulmonary arterial vasoconstriction resulting from interstitial fibrosis may also contribute to the development of pulmonary hypertension or cor pulmonale under these conditions. Bullous emphysema has been reported as another chronic complication of talc granulomatosis in intravenous opioid abusers.Septic pulmonary embolism is a frequent complication of injection drug abuse that may occur as a result of thrombophlebitis at the injection site or more commonly, tricuspid valve endocarditis. Mycotic aneurysms also occur as a consequence of seeding of the pulmonary vasculature with septic thromboemboli, and rupture of a pulmonary mycotic aneurysm may cause life-threatening hemoptysis
Opiate dependence can be viewed as a physical illness or a central nervous system disorder resulting from chronic opiate intake. Sudden opiate abstinence induces a traumatic disorder, the withdrawal syndrome, possibly leading to permanent damage to the cardiopulmonary and/or central nervous systems.
Pharmacological detoxification programs include the use of clonidine with or without methadone, midazolam, trazadone or buprenorphine;A different approach to detoxification from opioids emerged: the administration of a high-dose µ receptor antagonist during general anesthesia.Well-designed protocols accelerate detoxification and attenuate withdrawal symptoms. The procedure should result in 100% detoxification rates, should be safe, and should be accomplished in 4–6 h
Using a rapid detoxification protocol allows a more rapid introduction of opioid antagonist maintenance therapy with a subsequent reduction in relapse rates
Withdrawal is precipitated by the iv injection of high dose naloxone.Absence of response to a naloxone challenge may require six hours of general anesthesia with injection of high dose naloxone at repeated intervals.When the patient is stable and well oriented, a subjective opioid withdrawal scale (SOWS) is determined. . The SOWS should be less than 20.In the hours following ROD, naltrexone 50 mg po is given. Daily naltrexone 50 mg po for at least six months is part of the detoxification process. When the patient has been monitored for 24 hr, symptoms of withdrawal are within acceptable limits, and the patient meets the usual criteria for discharge from the recovery room of an outpatient facility, the patient may be released.
Many patients are able to return to work in a few days.