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Ethanol Abuse and Toxic Alcohol Ingestion. Chris Hall, PGY-5 McMaster University U of C Academic Day August 2, 2007. Objectives. Approach to the “intoxicated” patient Pharmacology of alcohols Common clinical scenarios in EtOH Diagnostic and management challenges of toxic alcohols
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Ethanol Abuse andToxic Alcohol Ingestion Chris Hall, PGY-5 McMaster University U of C Academic Day August 2, 2007
Objectives • Approach to the “intoxicated” patient • Pharmacology of alcohols • Common clinical scenarios in EtOH • Diagnostic and management challenges of toxic alcohols ***Case-based and evidence-centred
Case #1 • 56 yo male • “Known alcoholic” • Unresponsive on park bench • No witnesses; no apparent trauma • “Smells of alcohol” as per EMS
Case #1 • Afebrile, HR 102, BP 140/85, RR 22, O2 sat 91% • CBS: 5.5 • Neuro: GCS 11; moves 4 limbs • Sonorous resps; Gag present • Chest: scattered crackles • Abdo, extremities: WNL
Case #1 • Any additional information you’d like? • What is your working Dx? • How will you proceed from this point?
The “Intoxicated” Patient • V I T A M I N C D E • A E I O U T I P S • “Intracranial” vs. “Extracranial”
Intracranial Seizures Vascular Infectious Neoplastic Traumatic Extracranial O2 / CO2 Infectious Toxins / WD Metab. / Endo. Environmental The “Intoxicated” Patient
The “Intoxicated” Patient • Reasonable DDx for Case #1: • Ethanol / other co-ingestions • Head trauma • CNS / other infection • Hypoglycemia / AKA • Wernicke encephalopathy • Alcohol withdrawal (+/- seizures)
Immediate Action • Airway / Breathing • Hemodynamic stability • Reversible causes • The “Coma Cocktail” (?!)
Further Management • History and P/E • Investigations • Which ones?
Case #1 • TAKE HOME MESSAGE: • DO NOT assume EtOH to be the cause of the “intoxicated” patient’s presentation • Keep the differential broad; systematic approach to eliminate other DDx
Alcoholic Trivial Pursuit • What is “100-proof alcohol”? • 50% EtOH by weight
Alcoholic Trivial Pursuit • What is considered “one alcoholic drink”? • 15g of EtOH • 1 oz 50% (liquor) • 4 oz 12% (wine) • 10 oz 5% (beer)
Alcoholic Trivial Pursuit • How much EtOH would a 70kg male need to drink to reach an EtOH level of 30 mmol/L? • 3 • 5 • 7 • 9 • 11
Alcoholic Trivial Pursuit • TRUE OR FALSE: • Men are less susceptible to acute alcohol intoxication • Caffeine masks EtOH intoxication • Prickly pear is an antidote for veisalgia • Hydration accelerates metabolism of EtOH • Intoxication is lessened by co-ingesting food
Pharmacology • EtOH rapidly absorbed • Stomach and small bowel • Multifactorial effects on rate • Food • GI disease • Meds (gastric emptying) • Idiopathic
Pharmacology • EtOH metabolized by ADH and ALDH • Stomach and liver; 5-10% unchanged via urine • Gender / ethnic differences in metabolism • Rate: 3-4mM/h (non-drinker) up to 7.5mM/h (chronic drinker)
Clinical Presentation • CNS Effects: • GABA Agonism + NMDA Antagonism • Inebriation, poor impulse control, ataxia • “Set-up” for withdrawal • CVS Effects: • Vasodilation, reduced CO • Dysrhythmias
Clinical Presentation • GI Effects: • N/V/D volume loss • Pancreatitis, gastritis, hepatitis • GI Bleeding • Metabolic Effects: • HypoNa, Hypoglycemia • osmol gap; no anion gap • Ketonemia after binges
Clinical Presentation • Hematologic Effects: • Anemia ( MCV) • Thrombocytopenia • Lymphopenia
Case #2 • 46 yo male • CC: “Unwell” • HR: 115, BP 165/100, RR 25, sat 100% • Tremulous • Sweaty • Alert, not confused • Exam otherwise WNL
Case #2 • Discuss: • Your working / differential diagnoses • Your initial management and approach to this patient
Alcohol Withdrawal • GABA receptor downregulation + NMDA receptor upregulation • Anxiety, sweating, tremor, autonomic overdrive, altered LOC, seizures • Generally in chronic abusers
Spectrum of Illness • Simple Withdrawal • Alcoholic Hallucinosis • Withdrawal Seizures • Delirium Tremens
Alcohol Withdrawal: Rx • Holbrook et al (CMAJ 1999) • Metaanalysis of WD Rx • BZD vs placebo or other Rx • BZD better than placebo • More successful outcomes • Less likely to drop out of Rx • Unable to properly pool results otherwise
Choice of BZD? • Ritson et al, (Drug Alc Dependence 1986) • RCT; N=40 • Standing lorazepam vs diazepam • Less anxiety; smoother course with valium
Choice of BZD? • Diazepam is the traditional choice • Lorazepam is preferred in patients with severe liver disease
Benzodiazepines • Dosing • Diazepam: 5 mg iv / 10 mg po q 10 min • Lorazepam: 1-2 mg iv / 2 mg po q 15 min • NB: longer time of onset; beware dose stacking • Titrate to effect • (But how?)
CIWA • 10-item scale • Min score = 0, Max score = 67 • Score < 8 considered mild withdrawal (Rx threshold) • Takes 5 min to complete
Symptom-Guided Rx • 2002 Arch Int Med & 1994 JAMA: • 2 RCTs • CIWA-guided Rx reduces BZD use, length of Rx vs. standing BZD protocol • Guide therapy with symptoms; avoid standing dosing schedules • Do not fear huge doses
Adjunctive Rx • Carbamazepine • 2 RCTs (Am J Psych 1989; J Gen Int Med 2002) • Similar to BZD in Rx of withdrawal symptoms • Valproate • 1 RCT (Alc Clin Exp Res 2001) • Less BZD needed when Rx with VA
Simple Withdrawal: Rx • Adjuncts, cont’: • Beta Blockers • Clonidine • Haldol • Magnesium
Withdrawal: Disposition • RCT (NEJM, 1989) • CIWA < 15; no comorbidities • Outpatient Rx as safe as Inpatient Rx, cost less, lasted less time • Inpatients more likely to complete Rx • Outpatients got daily follow-up and BZD dosing
Withdrawal: Disposition • Discharge home if: • Mild withdrawal at time of d/c (CIWA < 8 - 15 after 4-6 h observation) • Easily controlled w/ BZD • Not intoxicated • Responsible supervision preferred • No prior hx of seizures or DT
Case #2 ,Part 2 • BZD sedation is ordered for the patient • 60 min later, patient is more tremulous, agitated • While trying to get out of bed, has generalized T/C sz
Case #2, Part 2 • What are your initial steps? • How will you treat this patient?
Withdrawal Seizures • Usually GTC, self-terminating • 15-25% have > 1 seizure • < 8% go into status • May herald onset of DT
Seizure Management • ABCs • Rule out reversible causes • Lorazepam likely longer anticonvulsant effect than diazepam
Seizure Management BZD (e.g. Ativan 2-4 mg iv) Phenobarbital 15-20 mg/kg Propofol / Midazolam / Pentobarb Inhalational Anaesthesia, paralysis, EEG monitoring
What about Dilantin? • EBM (Ann Emerg Med 1991 & 1994): • 2 RCTs; 55 & 147 patients • No difference in relapse of seizures vs placebo • Mechanism of action unlikely to affect seizures in EtOH withdrawal • Likely to have little impact on Rx
Withdrawal Seizures • Some Questions to ponder: • Who can be released from the ED? • When is a CT Head warranted? • When should patients start an anticonvulsant?
CT Head • New / changed seizures • Focal seizure • Focal examination / meningismus • Failure to recover usual mental status • Mental status out of proportion to EtOH • Recent head trauma • +/- fever (prior to LP?)
Disposition • Normal workup and exam • Single seizure • Withdrawal well-controlled • Not intoxicated • Adequate supervision / follow-up
Starting an Anticonvulsant • Controversial • Seizure may be due to withdrawal or may represent underlying epileptic d/o • Generally, leave it to neurology!
Case #3 • 60 yo male • “Alcoholic” by own report • 2-week “binge” until yesterday • Since then, N/V, AP, “dizziness & blurred vision”
Case #3 • HR 114, BP 105/60, RR 28, sat 100% • CBS: 3.0 • Chest: clear • Neuro: slightly drowsy; no focality; no tremor • Abdo: tender epigastrium • Urine dip: negative for ketones, blood, WBC
Case #3 • Working diagnosis / differential? • Approach to management?