Rosen & Barkin's 5-Minute Emergency Medicine Consult (490 page)

• Bind to μ, κ, and δ opiate receptors in the CNS and peripheral nervous system (PNS)
  
• Physical and psychological dependence occurs.
  
• Peak plasma levels:
  
  • PO: 1–2 hr
    
  • Intramuscular: 0.5–1 hr
    
  • Intravenous or intranasal: Seconds to minutes
    

• Overuse or abuse of oral prescription analgesics for moderate to severe pain
  
• Street preparations of opiate analogs may contain adulterants:
  
  • Cocaine
    
  • Clenbuterol
    
  • Phencyclidine
    
  • Strychnine
    
  • Dextromethorphan
    
  • Quinine
    
  • Scopolamine
    

DIAGNOSIS

• CNS:
  
  • CNS depression
    
  • Coma
    
  • Seizures
    
• GI:
  
  • Nausea
    
  • Vomiting
    
  • Constipation
    
• Cardiovascular:
  
  • Hypotension
    
  • Bradycardia
    
  • Palpitations
    
• Pulmonary:
  
  • Respiratory depression
    
  • Bronchospasm
    
  • Pulmonary edema
    
  • Apnea
    
• Other:
  
  • Miosis
    
  • Hypothermia
    
• Withdrawal:
  
  • HTN
    
  • Tachycardia
    
  • Tachypnea
    
  • Abdominal cramps
    
  • Diarrhea
    
  • Piloerection
    
  • Yawning
    

• Neonatal withdrawal:
  
  • Infants born to addicted mothers
    
  • Onset: 12–72 hr after birth
    
  • Irritability, tremors, poor feeding, and dehydration
    
• Diphenoxylate (Lomotil): Toxicity more severe in children than adults and may be fatal
  

Monitor vital signs and pulmonary status with significant exposure:

• Pulse oximetry or arterial blood gases
  
• CXR if persistent hypoxia or possible aspiration
  
• Abdominal radiograph if body packing suspected
  
• Perform a complete exam for occult sticky patches (e.g., fentanyl).
  

• Plasma opiate levels not clinically useful:
  
  • Treatment based on clinical presentation, not opiate level
    
• Urine toxicity screen for opiates may not identify some synthetic opioids (e.g., methadone).
  
• Acetaminophen level for overuse or abuse of oral prescription analgesic products
  

• Clonidine overdose
  
• Barbiturate overdose
  
• Benzodiazepine overdose
  
• γ-hydroxybutyrate (GHB) overdose
  
• Neuroleptic overdose
  
• Occult head injury
  

TREATMENT

• Transport all pills/pill bottles involved in overdose for identification in ED.
  
• Provide respiratory support.
  
• Administer naloxone.
  

• Check ABCs:
  
  • Airway control is essential.
    
  • Administer supplemental oxygen.
    
• Administer naloxone:
  
  • Reverses respiratory depression and coma in opiate overdoses
    
  • Intubate if naloxone does not reverse respiratory depression.
    

• Naloxone administration:
  
  • Start with low doses for opiate-habituated patients.
    
  • High doses (10 mg) may be required to reverse the effects of propoxyphene, methadone, and fentanyl.
    
  • Administer repeated doses that reversed symptoms, as needed every 20–60 min.
    
  • For long-acting opioids, consider an hourly infusion of 2/3 of the dose needed to reverse symptoms.
    
• Decontamination:
  
  • Administer activated charcoal for oral ingestion.
    
  • Administer whole-bowel irrigation with polyethylene glycol for asymptomatic body packers.
    
• Treat opiate withdrawal with clonidine or methadone.
  
• Hypotension:
  
  • 0.9% normal saline IV fluid bolus
    
  • Trendelenburg test
    
  • Initiate dopamine for resistant hypotension.
    
• Seizures:
  
  • Treat initially with diazepam.
    
  • Administer phenobarbital for persistent seizures.
    

• Activated charcoal: 1–2 g/kg PO
  
• Clonidine: 0.1–0.3 mg PO BID for 10 days; 0.1–0.2 mg/kg/d transdermal patch
  
• Diazepam: 5–10 mg IV (peds: 0.2–0.5 mg/kg IV) q10–15min
  
• Dopamine: 2–20 μ/kg/min; titrate to effect.
  
• Methadone: 15–40 mg/d
  
• Naloxone: 0.4–2 mg (peds: 0.1 mg/kg; neonate dose same as peds except if suspect neonatal withdrawal use 0.001 mg/kg IV) IV, IM, or nebulized
  
• Phenobarbital: 10–20 mg/kg IV (loading dose); monitor for respiratory depression
  
• Polyethylene glycol: 2 L/h until clear rectal effluent and/or passage of packets
  

FOLLOW-UP

• Symptomatic after oral overdose
  
• Repeated naloxone dosing or infusion needed to reverse symptoms
  
• Children <5 yr after diphenoxylate ingestion should be observed for 24 hr.
  
• Opiate body packers
  
• Persistent symptoms from concomitant toxin exposure (e.g., clenbuterol)
  

• Asymptomatic 6 hr after oral overdose
  
• Asymptomatic 4 hr after naloxone administration
  
• Complete elimination of opiate packets
  

• Substance abuse referral for patients with oral opiate abuse.
  
• Patients with unintentional (accidental) poisoning require poison prevention counseling.
  
• Patients with intentional (e.g., suicide) poisoning require psychiatric evaluation.
  

• Consider occult acetaminophen poisoning in chronic oral opioid–abusing patients.
  
• Buprenorphine may cause prolonged sedation in pediatric patients.
  
• Semisynthetic and synthetic opioids will not provide a positive opiate hospital drug screen result.
  

• Bailey JE, Campagna E, Dart RC. The underrecognized toll of prescription opioid abuse on young children.
  Ann Emerg Med
  . 2009;53(4):419–424.
  
• Centers for Disease Control and Prevention (CDC). Vital signs: Overdoses of prescription opioid pain relievers—United States, 1999–2008.
  MMWR Morb Mortal Wkly Rep
  . 2011;60(43):1487–1492.
  
• Enteen L, Bauer J, McLean R, et al. Overdose prevention and naloxone prescription for opioid users in San Francisco.
  J Urban Health
  . 2010;87(6):931–941.
  
• Hoffman RS, Kirrane BM, Marcus SM, et al. A descriptive study of an outbreak of clenbuterol-containing heroin.
  Ann Emerg Med
  . 2008;52(5):548–553.
  
• Weber JM, Tataris KL, Hoffman JD, et al. Can nebulized naloxone be used safely and effectively by emergency medical services for suspected opioid overdose?
  Prehosp Emerg Care
  . 2012;16(2):289–292.
  

CODES

• 965.00 Poisoning by opium (alkaloids), unspecified
  
• 965.01 Poisoning by heroin
  
• 965.02 Poisoning by methadone
  

BASICS

Unusual infections that occur when host suffers a decrease in resistance against normally nonpathogenic organisms