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1 Toxicology, Alcohol & Drug Abuse 2008 Types of Toxicological Emergencies Unintentional • • • • • • Dosage errors Idiosyncratic reactions Childhood poisoning Environmental exposure Occupational exposure Neglect and exposure 2 Intentional poisoning/overdose • Chemical warfare • Assault/homicide • Suicide attempts 3 Use of poison control centers Oregon Poison Control 1-800-452-7165 Evaluation of the poisoned patient 4 Scene Size-up Where are you? Who’s around you? Is there any potential danger? Any evidence of pill bottles, used needles, etc. 5 History • Provides a working diagnosis; notoriously unreliable • What - samples • How much • How • When • Why • What else 6 Physical exam Vitals • Airway • Stridor • Snoring • Vomitus • Gag reflex • Risk of aspiration 7 • Breathing evaluation • Baseline RR • Quality of respirations –Shallow; need early ventilatory support –Deep; underlying hypoxemia or metabolic acidosis • Early - noncardiogenic pulmonary edema • Later - ARDS 8 • Circulation • Baseline pulse rate and BP –Hypotension common –Hypertension occasionally; serious ie CVA • ECG monitoring –Tachyarrhythmias common; not usually serious perfusion problem –Bradyarrhythmias uncommon; more serious underlying metabolic problem 9 Temperature • Baseline temp. • Hypothermia and hyperthermia frequently accompany poisons 10 Neuro complications • Altered level of consciousness (AMS) frequent • Seizures one of most common • Mild drowsiness • Agitation • Hallucinations • Confused, combative • Coma • Medullary depression • Cardiopulmonary depression • Death 11 Underlying disease states • Asthma, COPD etc. increased risk for resp. compromise • Underlying cardiac disease increased risk for severe arrhythmias. 12 Supportive care • Prevent or limit respiratory, cardiac, neurologic complications • Oxygen, • IV • ECG 13 Respiratory complications • • • • Airway protection ET or NT intubation Bronchodilator therapy prn Positive pressure ventilation prn 14 Cardiovascular complications • Appropriate antiarrhythmics • Atropine • Pacing • Fluid challenge for hypotension • Vasodilators for hypertension 15 Neurologic complications • Anticonvulsants; diazepam/versed prn • Chemical restraints only compounds intoxication and may precipitate catastrophic cardiopulmonary complications 16 Routes of absorption • Ingestion • Inhalation • Injection • Absorption 17 Ingestion Most common route • Assessment findings • What? • When? • Quantity? • Alcohol? • Self-treatment? • Psychiatric care? • Weight? 18 Physical examination • Skin • Eyes • Mouth • Chest • Circulation • Abdomen 19 General management considerations • Prevent Aspiration • Intubation/RSI? • Fluids & Drugs • GI decontamination • Syrup of Ipecac –Reduces absorption by @ 30% –Interferes with activated charcoal • Gastric lavage –36-40 Fr. orogastric tube –After 1-2 hrs post ingestion questionable 20 • Activated charcoal • Agent of choice • Adsorbs molecules of chemicals on its surface • Reduces absorption by @ 50% • Dose 1 g/kg 21 Cathartics • Sorbitol, mag sulfate, mag citrate • Speed up motility • Studies show they don’t positively affect patient outcome • Liquid stools • Dehydration, electrolyte imbalances occur • Administration of activated charcoal 20-30 min. prior to gastric lavage doubles effectiveness 22 How do people poison themselves? 23 They Inhale it • Paint, other hydrocarbons • Carbon monoxide • Ammonia • Chlorine • Freon • Toxic vapors, fumes, aerosols • Mace, mustard gas 24 What do they look like? Primarily respiratory • Tachypnea, cough, hoarseness, stridor, dyspnea, retractions, wheezing, chest pain or tightness, rales, rhonchi Cardiac: • Dysrhythmias CNS • Dizziness, H/A, confusion, seizures, hallucinations, coma 25 Carbon Monoxide Inadvertant • Faulty furnace • Indoor heating source Purposeful • Suicide Poisonous Gases Oxygen robbing Chlorine Warfare • Chlorine • Mustard gas • Bromine 28 Now what? Be safe! Remove patient from environment Exam Provide supportive care Contact Poison Control and follow directions 29 They inject it • IV drug abuse – more later • Venomous bites and stings • Bees, hornets, yellow jackets, wasps, ants (only females) • Spiders, ticks, other arachnids; scorpions • Snakes • Marine animals; jelly fish, stingrays, anemones, coral, fish 30 Ticks/Lyme Disease Frequently requires Antibiotics (Amoxicillin, Zithromax) Tick generally must be attached for 24-48 hours 31 Results in immediate & delayed reactions • Immediate reaction • Rash • Fever • Malaise • Fatigue • H/A • Muscle & joint aches • Sore throat • Sinus infection 32 Delayed reaction • • • • • • • • • • • • Chronic malaise/fatigue Muscle pain/joint pain with/without arthritis Neuropathy Tremor Bell’s palsy Meningitis Vision problems (double vision, photophobia) Vestibular problems Seizures Cardiac symptoms N/V Immune suppression 33 Hymenoptera (Bee stings, Wasp stings, Ants) • Bumblebees, Sweat bees, Honeybees; Hornets, Yellow jackets; Fire ants, Harvester ants • Type of reaction • Local; • Toxic; 10 or more stings – N/V/D, light-headedness, syncope, H/A, fever, drowsiness, muscle spasms, edema, seizures – Sx subside w/in 48 hrs 34 Bees and Bugs Systemic/anaphylactic: • The shorter the onset, more severe the reaction • Initial sx: itching eyes, facial flushing, generalized urticaria, dry cough • Sx intensify; chest or throat constriction, wheezing, dyspnea, cyanosis, abdominal cramps, N/V/D, vertigo, chills, fever, shock, loss of consciousness • Reaction can be fatal in 30 min. 35 Bees and Bugs Delayed reaction • Serum-sickness-like sx; fever, malaise, H/A, urticaria, lymphadenopathy appears 10-14 days later. Dx: difficult • Honeybees; leaves it’s stinger with venom sac attached • Yellow Jackets: nest in ground • Wasps: under eaves or windowsills • Southern US Fire Ants; groupings of 3-4 stings and pustules 36 Bees and Bugs Tx: • Scrape honeybees stinger out; don’t squeeze; remove quickly • Wash sting sites with soap and water • Ice packs • Benadryl, Prednisone • Epinephrine 1:1000 0.3 - 0.5 mg sq IF SYSTEMIC 37 Brown Recluse Spiders (Fiddleback spider) Southern, midwestern states • Tennessee, Arkansas, Oklahoma, Texas, Hawaii, California • 15mm long. 6 eyes in a circle • Lives in dark, dry locations • Violin-shaped markings on back 38 Does it hurt? Usually painless Bites occur at night Local reaction • Initially, small erythematous macule surrounded by a white ring • Over next 8 hours, localized pain, redness, swelling • Tissue necrosis over days > weeks Chills, fever, N/V, joint pain, DIC Tx: Diphenhydramine; supportive 39 40 Black Widow spiders Live in all parts of continental US Found in woodpiles or brush Female spider bites • Orange hourglass on black abdomen 41 Does it hurt? Immediate localized pain, redness, swelling. Progressive muscle spasms of all large muscle groups can occur N/V, sweating, seizures, paralysis, decreased level of consciousness. Management: Supportive care; • Consider Diazepam • 2 – 10 mg IVP • or Calcium gluconate • 0.1 – 0.2 mg/kg of 10% solution. • Monitor B/P • Antivenin is available 42 Scorpion stings All species can sting, = localized pain Only bark scorpion has caused fatalities • Mostly in Arizona, California, Nevada, New Mexico, Texas. • Move mostly at night • Venom stored in bulb at end of tail 43 Does it hurt? Venom acts on nervous system • Burning, tingling effect • Gradually progresses to numbness. Systemic effects • • • • Slurred speech, restlessness Hyperactivity in 80% of children Muscle twitching, seizures Salivation, abdominal cramping, N/V Management: Supportive • Apply constricting band above wound site – watch band – occludes lymphatic flow only • Avoid analgesics; may increase toxicity 44 Snakebite • 8000 bites/yr - mortality is @ 50/yr • N. Carolina has highest % • Peak months July, August 6am - 9 pm 45 Pit Vipers Cottonmouth, rattlesnake, copperhead • Indentation 1/2-way between eye and nostril • Hollow, retractable fangs • Vertical pupils • Triangular head 46 Pit Vipers (cont.) Venom contains enzymes that may destroy proteins, other tissue components; destroys RBCs, affects blood clotting Death from shock possible in 30 minutes • Most occur 6-30 hours 47 Pit Vipers (cont.) S/S: Fang marks, swelling and pain • • • • • Weakness, dizziness, faintness Sweating/chills Thirst, N/V, Diarrhea, Tachycardia, hypotension Bloody urine Tx: Keep pt. Supine • Immobilize limb • Maintain extremity in neutral position • DO NOT apply constricting bands, Ice, etc. 48 Coral snakes Distinct pattern of red and black bands wider than interspaced yellow rings “Red on yellow, kill a fellow”/coral snake “Red on black, venom •Venom •Affects coagulation lack”/harmless snake •Affects endothelium of vessels •Paralyzes activity of white blood cells •Neurotoxins A & B affect nervous system; esp. cardiorespiratory centers49 Coral Snakes (cont.) May be NO effects for 12-24 hours • Localized numbness, weakness, drowsiness • Ataxia, slurred speech, excessive salivation • Paralysis of tongue, larynx • Drooping eyelids, double vision, dilated pupils • Abdominal pain, N/V • Hypotension, Respiratory failure • Seizures 50 Coral Snakes (cont.) Size of victim important; condition of victim will seriously affect outcome Location very important; bites on head and trunk 2-3x more dangerous; bites on upper extremities more serious than lower. 51 Coral Snakes (cont.) Tx: • Wash wound with copious amounts of water • Apply compression bandage, keep extremity at level of heart • Immmobilize limb • Transport for antivenin • Do NOT apply ice, cold pack, freon sprays, or incise wound 52 Marine Animal Injection Jellyfish, Coral, Sea urchins, Sting rays Secondary infections S/S: intense local pain, swelling • Weakness, N/V • Dyspnea, tachycardia • Hypotension, shock Tx: Supportive care • Consider a constricting band between heart, & wound; occlude lymphatic flow only • Heat or hot water • Meat tenderizer 53 Poisoning By Absorption Surface absorption • Poisonous plants; ivy, sumac, oak • Organophosphates 54 Now What? Management considerations • • • • • • • Remove patient from environment Wear protective clothing Remove pt. clothing Initiate supportive measures Contact poison control Soap and water Decontaminate eyes with 15-30 min. Water flush • Supportive care 55 Cholinergics Pesticides (organophosphates, carbamates) Nerve agents (sarin, Soman) 56 Cholinergics (cont.) Findings • SLUDGE • Headache, Dizziness, Weakness, Nausea • Bradycardia, wheezing, bronchoconstriction, myosis, coma, convulsions, diaphoresis Management • Decontamination • Airway and ventilation • Aggressive airway management • Circulation 57 Cholinergics (cont.) • Pharmacological • Atropine 2 – 5 mg IV q 15-30 min. until vitals improve • Pralidoxime chloride (2-PAM) • Diazepam 2 – 10 mg IV for seizure control • Activated charcoal – if ingested & gag reflex intact • Transport considerations • Protect self • Notify receiving hospital • May require decontamination outside ED 58 Caustic substances Acids, alkalis • 12,000 exposures/yr • 150 major complications/deaths • Plumbing liquids • Cause tissue coagulation, necrosis • S/S - Acids: pH <2 • Eschar at burn site • Local burns to mouth, throat • Esophagus usually not damaged • Stomach lining injured • Immediate, severe pain • Acidemia 59 Alkali's: pH > 12.5 • Induce liquefaction necrosis • Pain often delayed • Cause perforation, bleeding, inflammation of central chest structures • W/in 2-3 days, complete loss of protective mucosal tissue • S/S: • Facial burns, pain in lips, tongue, throat, gums • Drooling, trouble swallowing • Hoarseness, stridor, SOB • shock 60 Tx: • • • • • • Aggressive, rapid Prevent injury to rescuers Airway management critical Cricothyrotomy Don’t use activated charcoal Rapid transport 61 Hydrofluoric Acid Used to etch glass Extremely toxic Penetrates deeply into tissues; inactivated only by contact with calcium; settles in tissues as salt • Causes total disruption of cell functioning, bone destruction S/S: burning at site of contact, SOB, confusion, palpitations, muscle cramps Tx: Supportive: Immerse affected limb in ice water with Mag. Sulfate or calcium salts 62 Hydrocarbons Organic compounds; • Kerosene, turpentine, mineral oil, chloroform, etc. • Lighter fluid, paint, glue, lubricants, solvents, aerosol propellants. S/S: • Burns, wheezing, dyspnea, slurred speech, ataxia, obtundation • Foot and wrist drop with numbness, tingling • Cardiac dysrhythmias Tx: Rarely serious – call poison control 63 Tricyclic antidepressants Narrow therapeutic index • Amitrriptyline, Elavil, amoxapine, clomipramine, doxepin, imipramine, nortriptyline S/S: dry mouth, blurred vision, urinary retention, constipation, confusion, hallucinations, hyperthermia, respiratory depression, seizures, tachycardia, hypotension, heart block, wide QRS, Torsades de pointes Tx: Sodium Bicarbonate, 1 mEq/kg 64 MAO Inhibitors Atapryl, Eldepryl Relatively unpopular • Narrow therapeutic index • Serious interactions with red wine, cheese Symptoms may not appear for up to 6 hours • Headache, agitation, restlessness, tremor • Nausea, palpitations, tachycardia, hypertension, hyperthermia, bradycardia, hypotension, coma, death No antidote available; tx life-threatening sx. 65 Hallucinogens LSD, PCP, peyote, mushrooms, jimson weed, mescaline • “Psychedelic” - visual or tactile PCP • Ketamine still used • Powdered or solution; added to tobacco or marijuana • Onset in 2-5 min.; Peak effect in 15 min. • Elimination half-life about 7 h - 3 days. 66 LSD • Blotter acid, sugar cubes, gelatin • Sx in 1/2 - 1 hr; peak in 2 hrs (paranoia may occur), acute psychosis may persist for days 67 • Morning Glory • Mescaline/Peyote cactus • 6-12 buttons required to produce hallucinogenic effects • N/V, blurred vision, hypertension, tachycardia • Effects peak at 2 hrs, last for 6-12 hrs • Religious ceremonies • Tx with rest and reassurance 68 Mushrooms; psilocybin or ibotenic acidmagic mushrooms • Common in US; pacific NW, texas, florida, hawaii • Religious ceremonies since aztec • Eaten raw, brewed in soup or tea, or dried • GI discomfort in 15-30 min. N/V • Effects last from 4-12 hrs 69 Nutmeg; common in foods and herbal remedies • Myristicin is major component • 10-50 g of fresh nutmeg (2-9 whole nutmegs) • Sx in 3-6 hrs; N/V, abdominal pain • Cold extremities with weak pulses shallow respirations; sx resolve in 24 hr with supportive care 70 Designer amphetamines • Adam, Eve, Ecstasy • Effects are drug and dose dependent • Severe psychomotor agitation • Disorders of thought process • Hypertension, seizures, DIC, ARDS, death • Management supportive 71 Marijuana • Cannabis sativa; marijuana and hashish • Medicinal qualities in china > 4000 years ago • Today; glaucoma and chronic pain • Most commonly used illicit substance after alcohol and tobacco • THC levels peak about 8 min after inhalation, and 45 min. after ingestion. Effects last 2-6 hrs. 72 73 Narcotics Heroin, methadone, morphine, codeine, meperidine, hydromorphone (Dilaudid), hydrocodone (Percodan) • Street heroin cut with quinine, lactose, sucrose, mannitol, talc, procaine, baking soda. • Effects include drowsiness, euphoria, miosis, decreased respiration, N/V, respiratory arrest 74 75 Withdrawal • Piloerection, lacrimation, yawning, rhinorrhea, sweating, nasal stuffiness, myalgia, vomiting, abdominal cramping, diarrhea, irritable, hyperactive, confused 76 Narcotic overdose • Cardinal findings; pinpoint pupils, hypoventilation Tx: Airway, ventilation, circulation Naloxone, 0.4-2.0 mg/0.01 mg/kg in child, SQ, IM, IV, ET; effective in 1-2 min. • Naloxone acts as antagonist at opiate receptor sites • Overdose often mixed • Serum half-life of Narcan is 1 hr with action duration of 2-3 hr. (methadone half-life 72 hr). 77 Complications of narcotic abuse • Skin ulcers or lesions • nonpitting edema of extremities • Infection • Abscesses, Cellulitis, Thrombophlebitis • Endocarditis • Malaria (1929) • Tetanus (1876) esp. female, subcu injectors 78 • Hepatic complications; most common • GI complications • Ilius • Fecal impaction • CNS complications • Meningitis • Spinal abscess 79 Cocaine Most common cause of drug related deaths • Plant alkaloid found in coca plant. Leaves are crushed with a hydrocarbon solvent followed by extraction of alkaloid with sulfuric acid • Smoked, snorted, or injected • Crack is almost pure cocaine vaporizes at high temp. • Absorbed from all sites; mucous membranes, GI tract, respiratory tree. 80 Cocaine Smoked, injected, snorted, swallowed Intensity & duration depends on route 1997 – 1.5 million Americans use Drug most frequently involved in ED visits Often used with Valium, Ativan, Heroin as upper/downer combo Adolescents combine Cocaine, Marijuana, Alcohol 81 Short-term effects Pleasure Increased alertness Paranoia Vasoconstriction Myocardial damage Dysrhythmias Death 82 Long term effects Severe depression Loss of energy Damage to • • • • Heart Lung Brain Kidneys 83 84 85 Cocaine (cont.) • Intranasal admin peak effect in 1/2 hr • GI peak effect in 90 min. • IV and inhalation peak at 30 seconds to 2 min. • Tachycardia, hypertension, hyperthermia, agitation, seizures are common. 86 Cocaine (cont.) AMI common; onset immediate > 24 hr. • Coronary artery spasm, thrombosis, atrial and ventricular arrhythmias, aortic rupture, CHF, QRS widening Spontaneous pneumothorax and pneumomediastinum possible 2ndary to deep breath holding CVA OB risks Renal failure 87 Cocaine (cont.) Topical cocaine Management • Sedation, control of hyperthermia and seizures, fluids. 88 Amphetamines & Amphetaminie-like Drugs • • • • • • • Benzedrine Dexedrine Ritalin Midol Vicks inhaler Bronkaid tabs Alka-Seltzer plus, Allerest, Contac, Dexatrim, Dimetapp, Novahistine tabs, Extra-strength Sinutab, Triaminic • Actifed, Drixoral, Novahistine, Sudafed 89 Amphetamines (cont.) • First synthesized in 1887, but not commercially available until 1932 • Similar to epinephrine, norepinephrine Effects: • Restlessness, hyperactivity, repetitive behavior, anorexia, sleep reduction • Rapidly absorbed from GI tract; peak levels within 1 hr. 90 Amphetamines (cont.) Toxicity: • Diaphoresis, extreme restlessness, repetitive and bizarre behavior, coma, intracranial hemorrhage, flushing, tachycardia, hypertension, arrhythmias, MI, N/V/D • Abrupt withdrawal rarely life-threatening. Depression, increased appetite, cramps, N/D, HA. • Care supportive 91 Methamphetamines 92 80% children in foster care are Meth related Barbiturates • First introduced as sedative in 1903. Currently used to treat seizures, induction of anesthesia, treatment of ICP • • • • Methohexital Phenobarbital Secobarbital Primadone 100 Barbiturates (cont.) Barb. intoxication mimics alcohol intoxication. Rule of thumb; 10x hypnotic dose can produce severe toxicity. Treatment: ET, gastric lavage, IV, diuresis, Hemodialysis 101 Benzodiazepines Commonly used for anxiety, insomnia, seizures, Alcohol withdrawal, conscious sedation, general anesthesia. • • • • • • • • • Xanax Librium Klonopin Tranxene Valium Dalmane Ativan Versed Halcion 102 Benzodiazepines (cont.) Predominantly CNS effects, well absorbed from GI tract. IM injection is unpredictable 103 Benzodiazepines (cont.) Most serious toxicity occurs in ingestion of other agents or parenteral administration. CNS effects; • Drowsiness, dizziness, slurred speech, confusion, ataxia, intellectual impairment. Managment: • • • • • Dextrose, thiamine, naloxone Do not induce vomiting Give activated charcoal Gastric lavage Monitor closely 104 Cyanide Potent cellular toxin; as little as 50 mg may cause death. • Extract of bitter almonds/cherry laurel leaves, extracts of apricot, cherry, peach pits • Silver polish • Prolonged exposure to IV nitroprusside • Burning of synthetics and wool, silk, vinyl, polyurethane Several hours exposure (<50 ppm) can cause sx Recovery is rapid after removal. 105 Exposure to 100 ppm may be fatal in 30 min. Sx: • • • • • • • Severe dyspnea, Loss of consc., Seizures, Arrhythmias, HA, Drowsiness, Paralysis, Pulmonary edema, Bright red retinal vessels, smell of bitter almonds important clues. Tx: amyl nitrite for inhalation, 10 ml of 3% solution of sodium nitrite for IV infusion.; Give 300 mg, followed by 12.5 g of sodium thiosulfate. 106 Drug abuse • Epidemiology • Incidence • Morbidity/mortality • Risk factors • Prevention • Psychological issues • Psycho-social issues 107 Drug abuse (cont.) Pathophysiology of long term drug abuse • End-organ damage • Brain, liver, heart • Malnutrition • Habituation/dependence/addiction • Tolerance • Withdrawal syndromes 108 Alcoholism - Ethanol • Incidence • Morbidity/mortality – 42% traffic fatalities, 69% drownings, 23% suicides – 100,000+ deaths/yr • Risk factors • Prevention • Psychological issues • Psycho-social issues 109 Alcoholism (cont.) End-organ damage • Brain • Liver • Heart • Bone • Pancreas 110 Alcoholism – Clinical Manifestations Altered Immunity Anorexia Dysrhythmias Coma Irritability and disorientation Muscle cramps Poor wound healing Seizures Tremor and ataxia 111 Alcoholism (cont.) Malnutrition Withdrawal syndrome Wernicke’s encephalopathy (disorder of the brain) 112 Alcoholism – Body System Disturbances Fluid and electrolyte from diuresis GI disorders (bleeds, esophageal varices) Liver (cirrhosis) Pancreatitis Cardiac and skeletal muscle myopathy Immune suppression Trauma (suppressed clotting factors) 113 Prehospital concerns Delirium Tremens (DT’s) • Treat symptomatically • Valium/Versed • Rehydration 114 Wernicke-Korsakoff’s syndrome • Personality; psychosis, polyneuritis, disorientation, muttering delirium, insomnia, illusions, hallucinations • Classic triad; ataxia, ophthalmoplegia (nystagmus and 6th nerve palsy), and altered mental status; also, hypothermia, coma, hypotension 115 Methanol • Antifreeze, paint solvent, Sterno, gasoline additives • Life-threat even with small amount; 30 ml of 100% methanol lethal; • Converted in liver to formaldehyde to formate = cellular hypoxia. • S/S: visual sx-photophobia, blurred vision, dilated pupils; CNS depression; abd. Pn; N/V; metabolic acidosis. Onset 1 hr - 72 hrs 116 Ethylene Glycol • Colorless, oderless, sweet-tasting, nonvolatile liquid • Detergents, paints, pharmaceuticals, polishes, antifreeze, lysol spray, coolants • Toxicity due primarily to accumulation of toxic metabolites. • CNS sx 1-12 hr later: Ataxia, nystagmus, seizures, hallucination, coma 117 Ethylene Glycol (cont.) Cardiopulmonary sx 12-72 hrs later: Tachycardia, tachypnea, mild HTN, pneumonia, pulmonary edema, cardiac failure Renal failure w/in 24-72 hrs Tx: Gastric lavage, Alcohol, calcium chloride 118 Salicylates - aspirin (acetylsalicylic acid) • Oil of Wintergreen (methyl salicylate) • Darvon, Percodan, Fiorinal Directly stimulates respiratory centers in brainstem, = respiratory alkalosis. Causes mobilization of glycogen stores and inhibits gluconeogenesis, = hyperglycemia, normoglycemia, hypoglycemia 119 Salicylates - ASA S/S: • GI irritation, Upper GI bleeding, persistant vomiting • Mixed respiratory and metabolic acidosis • Confusion, lethargy, convulsions, respiratory arrest, coma, brain death, cardiac toxicity, significant hyperthermia, pulmonary edema 120 Salicylates - ASA Toxic doses • Peak serum levels in 18-24 hrs, although toxic levels within 6 hours. • Therapeutic levels, salicylate mainly cleared by hepatic metabolism • Toxic levels, renal excretion is major route of elimination • 150-300 mg/kg = mild-moderate toxicity; hyperpnea, vomiting, diaphoresis, tinnitus, acid/base disturbances 121 Salicylates - ASA Tx: • Activated charcoal • IV fluids • D50 • Hemodialysis 122 Acetaminophen poisoning (APAP) • Tylenol, Datril • Poisoning may result in fatal hepatic necrosis • Therapeutic dose 15 mg/kg q 4-6h (children) max daily dose 80 mg/kg • 325-1000 mg q 4 h (adults) max daily dose 4 g • Eliminated primarily by hepatic metabolism • Mechanism of toxicity unclear; a highly reactive metabolite is thought to cause hepatic necrosis by binding to protein macromolecules 123 Acetaminophen poisoning (APAP) Toxic doses • 140 mg/kg in children • 7/5 g in adults Toxicity: • Stage I: 1/2 - 24 h • N/V, Anorexia, malaise, pallor, diaphoresis • Stage II: 24-48 h • Transient clinical improvement • RUQ pain with liver enlargement, tenderness • Pancreatitis • Oliguria 124 Acetaminophen poisoning (APAP) Toxicity: • Stage III: 72-96 h • GI sx reappear, persist, or worsen • Jaundice • SGOT, SG • Stage IV: 4 d - 2 weeks • Resolution or progressive hepatic failure 125 Overdose guidelines Alcohol – thiamine, D50W Cocaine – Benzodiazepines • Beta blockers absolutely contraindicated Narcotics/opiates – naloxone Amphetamines – benzodiazepines, haldol Hallucinogens – benzodiazepines, haldol Benzodiazepines – flumazenil Barbiturates – forced diuresis, alkalinization of urine 126 127 128 Bye-Bye now~ 129