Anesthesia and the Addict Howard F. Armour CRNA, MS

Definitions Substance Abuse – Self Administration deviating from accepted medical or social use. Physical dependence – drug is necessary for normal physiological function or to prevent withdrawal. Withdrawal – rebound in physiological systems modified by drug. Tolerance – increased doses of drug required to produce same effects as smaller doses did previously.

Problems Cross Tolerance Chronic Abuse – Increased requirements Acute Abuse – Decreased requirements Withdrawal

Drug Overdose Leading cause of unconsciousness in ER Secure Airway – cuffed tube Monitor Temperature for Hypothermia Hemodialysis

Alcohol Disease – genetic, psychosocial and environmental factors Affects 10,000,000 Americans – 200,000 deaths annually Up to 1/3 of adult patients have medical problems related to alcohol

Risk Factors Male Gender Family History

Treatment AbstinenceDisulfram Side effects Drug Interactions

Withdrawal Syndrome Early Symptoms Treatment – resume alcohol ingestion or administer a barbiturate or benzodiazipine Protect the Airway Delerium Tremens

Management of Anesthesia DisulframHepatoxicity Drug Interactions HypotensionPolyneuropathy Avoid Alcohol Skin Prep

Management of Anesthesia Pathophysiological Changes Enzyme Induction/inhibition AnemiaThrombocytopeniaHypoprotinemia Esophageal Varices Cardiomyopathy Decreased Plasmacholinesterase Elevated Transaminases

Management of Anesthesia Intoxicated Patient Increased Risk of Aspiration – RSI Decreased Anesthetic Requirements

Cocaine 30,000,000 have used cocaine 5,000,000 use it regularly Extremely addictive

Side Effects Due to enhanced sympathetic nervous system activity Lung Damage associated with smoking Nasal atrophy Death from apnea, seizures or cardiac dysrhythmias

Management of Anesthesia If intoxicated – consider vulnerability to ischemia or dysrhytmias Intoxicated – Increased MAC Thrombocytopenia Use Neosynephrine for hypotension Maximum dose of Cocaine topically is 1.5 mg/kg for nasotracheal intubation 1.5 mg/kg for nasotracheal intubation

Opioids Possible to become addicted in less than 14 days if drug is administered in increasing doses Numerous associated medical problems CellulitisTetanusEndocarditisHepatitisAIDS

Opioids Tolerance Overdose – Respiratory depression Withdrawal Syndrome Prevention – Narcotics or Methadone Clonidine

Management of Anesthesia Preop – Narcotics or Methadone IV Access Volatile Anesthetic with Narcotics Hypotension ? Lighten Anesthesia FluidsVasopressorSteroidsNarcotics

Barbituates Not associated with major pathophysiological changes Tolerance – Lethal dose does not increase at the same rate Withdrawal - seizures

Management of Anesthesia Cross tolerance to anesthetics? Acute administration decreases anesthetic requirements Microenzyme induction Venous access is a problem in IV barbituate users

Benzodiazipines Symptoms of withdrawal slower to develop than with Barbituates Anesthetic considerations similar to those of chronic barbiturate user Specific antagonist - Fluazemil

Amphetamines Stimulate release of catecholamines Chronic abuse results in depletion of catecholamines

Management of Anesthesia Intoxicated patient may exhibit hypertension, tachycardia, increased temperature and increased MAC Chronic use depletes catecholamines – may attenuate response to indirect vasopressors Treat hypotension with fluids and neosynephrine

Marijuana Increased sympathetic nervous system Tachycardia Chronic use may lead to pulmonary problems May have plasmacholinesterase deficiency

Management of Anesthesia Treat tachycardia with beta bockers Barbiturate and ketamine sleep time prolonged Opioid respiratory depression potentiated