Opioids Objectives Understand opioids overdose pathophysiology. Presentations of opioids toxicity Diagnostic strategies of opioids toxicity Management of opioids toxicity Diagnosis and Management of opioids withdrawal Zohair Al Aseri MD,FRCPC EM & CCM

PERSPECTIVE Opioid applies to all natural, synthetic, and semi synthetic agents with morphine-likeactions. narcotic refers to any agent that induces sleep and is non specific Zohair Al Aseri MD,FRCPC EM & CCM

Misuse of pharmaceutical opioid PERSPECTIVE Misuse of pharmaceutical opioid Injection is the most common route, followed by inhalation, smoking and ingestion. Zohair Al Aseri MD,FRCPC EM & CCM

Pathophysiology and Pharmacology Toxicity Although different opioids have receptor preferences in therapeutic or low doses, this specificity is lost at higher doses. Zohair Al Aseri MD,FRCPC EM & CCM

Pathophysiology and Pharmacology Toxicity Opioids are well absorbed after GI (oral and rectal) or parenteral administration but also through nasal, buccal, pulmonary, and transdermal routes, depending on the lipid solubility of the specific opioid. Heroin is usually abused through intravenous and subcutaneous routes, but it is also absorbed after nasal administration because it is lipid soluble. Zohair Al Aseri MD,FRCPC EM & CCM

Pathophysiology and Pharmacology Toxicity With therapeutic doses, absorption is complete within 1 or 2 hours. Absorption and clinical effects of toxicity may be prolonged after overdose, however, because gastric emptying is delayed. Most opioids have a large volume of distribution. Zohair Al Aseri MD,FRCPC EM & CCM

Pathophysiology and Pharmacology Toxicity Heroin peaks in the serum within 1 minute of intravenous injection, 3 to 5 minutes of intranasal administration, and 10 minutes of subcutaneous injection. Heroin's lipophilic nature allows for rapid transport across the blood-brain barrier into the CNS. Zohair Al Aseri MD,FRCPC EM & CCM

CLINICAL FEATURES Toxicity The toxidrome of opioid toxicity is CNS depression Respiratory depression Miosis Zohair Al Aseri MD,FRCPC EM & CCM

Neurologic CNS depression Well-recognized manifestation of opioid toxicity. Hypoxia from CNS depression and respiratory depression also causes many neurologic complications. Dysphoria and acute psychosis may occur with an agonist-antagonist opioid. Zohair Al Aseri MD,FRCPC EM & CCM

Neurologic Seizures Meperidine-related seizures are probably caused by accumulation of normeperidine with repeated doses Seizures may also result from hypoxia with overdose of any opioid. Zohair Al Aseri MD,FRCPC EM & CCM

Neurologic Parkinsonian symptoms In intravenous drug abusers The syndrome is irreversible in some patients Zohair Al Aseri MD,FRCPC EM & CCM

Serotonin syndromeis a clinical triad of Neurologic Serotonin syndromeis a clinical triad of mental status changes autonomic instability neuromuscular changes May be fatal. Meperidine and dextromethorphan have serotoninergic properties and have been associated with serotonin syndrome. Zohair Al Aseri MD,FRCPC EM & CCM

Respiratory Decrease respiratory rate and tidal volume Overdose of an agonist-antagonist agent produces less significant respiratory depression Bronchospasm is rare with heroin use in asthmatic and nonasthmatic patients and occurs mostly after inhalational exposure. Acute lung injury occurs with therapeutic opioid use but is much more common after overdose Zohair Al Aseri MD,FRCPC EM & CCM

In more than 90% of heroin overdoses, results in miosis. Ophthalmologic In more than 90% of heroin overdoses, results in miosis. Gastrointestinal Nausea and vomiting are common with therapeutic opioid use and also with overdose. Severe cases may develop ileus Genitourinary Urinary retention from urethral sphincter spasm and decreased detrusor tone. Zohair Al Aseri MD,FRCPC EM & CCM

Opioids cause mild hypotension and relative bradycardia. Cardiovascular Opioids cause mild hypotension and relative bradycardia. Zohair Al Aseri MD,FRCPC EM & CCM

Dermatologic Pruritus, flushing, and urticaria occur after administration of certain opioids that release histamine (e.g., morphine) Zohair Al Aseri MD,FRCPC EM & CCM

Metabolic Hypoglycemia occurs, mechanismis unclear. Hypothermia has been reported Zohair Al Aseri MD,FRCPC EM & CCM

Withdrawal Increased sympathetic discharge and adrenergic hyperactivity are responsible for the clinical symptoms and signs. Withdrawal is associated with CNS excitation, tachypnea, and mydriasis. Pulse and blood pressure are also increased. Although these can be uncomfortable, they are typically not life-threatening. Zohair Al Aseri MD,FRCPC EM & CCM

Withdrawal Nausea, vomiting, diarrhea, and abdominal cramps are common in withdrawal. They can be significant and lead to dehydration and electrolyte abnormalities. Zohair Al Aseri MD,FRCPC EM & CCM

DIAGNOSTIC STRATEGIES History and physical examination Hypoglycemia Abdominal radiograph may identify packets of opioids or other illicit substances in a body packer. acetaminophen and salicylate levels should be checked because many prescription opioids are available in combination products. Zohair Al Aseri MD,FRCPC EM & CCM

DIAGNOSTIC STRATEGIES As with opioid toxicity, no diagnostic test exists for opioid withdrawal. Zohair Al Aseri MD,FRCPC EM & CCM

If reversal is not achieved with antidote MANAGEMENT airway, oxygenation, and ventilation is of vital importance in patients with opioid toxicity. If reversal is not achieved with antidote Zohair Al Aseri MD,FRCPC EM & CCM

MANAGEMENT Circulatory support usually does not require more than a crystalloid infusion. Most opioids have a large volume of distribution and cannot be cleared by dialysis. Zohair Al Aseri MD,FRCPC EM & CCM

Gastrointestinal Decontamination MANAGEMENT Gastrointestinal Decontamination is often unnecessary because the antidote can reverse the effects. Zohair Al Aseri MD,FRCPC EM & CCM

MANAGEMENT Antidote Naloxone a pure opioid antagonist is the antidote most frequently used to reverse opioid toxicity. Naloxone has a rapid onset of action. Naloxone is indicated for patients with opioid intoxication who have significant CNS or respiratory depression. Zohair Al Aseri MD,FRCPC EM & CCM

DISPOSITION Toxicity Patients with opioid toxicity are usually treated successfully in the emergency department, sometimes in conjunction with the emergency department observation unit. Patients who receive naloxone should be observed for 2 hours to assess the extent of re- sedation. Zohair Al Aseri MD,FRCPC EM & CCM

Zohair Al Aseri MD,FRCPC EM & CCM