Accidental Drug Ingestion & Overdose: Approach to Treatment Flashcards
What should be the initial approach to pharmacological intoxications?
Obtaining an appropriate history
Immediate stabilization and triage
Performing a thorough physical exam
Initiating treatment: decontamination, detoxification, symptomatic and supportive care of the patient
What are the big 6 that should be looked at on presentation?
Temperature Pulse Respiration Blood pressure Pulse oximetry ECG
What 5 things should be evaluated on presentation?
Airway Breathhing Circulation Dysfunction of neurologic system Exam
What diagnostics should be done on presentation?
Blood tests
Urine for UA, culture, drug tests
Imaging
What measures might be taken to achieve stabilization?
Oxygen Intubation Fluids Dextrose Calcium Temperature support Anti-seizure medications Anti-emetics
What is the goal fro decontamination?
Inhibit or minimize further toxicant absorption
To promote excretion or elimination of the toxicant from the body
What are the decontamination techniques?
Ocular Dermal Inhalation Injection Gastrointestinal Forced diuresis Surgical removal
How much of the ingested material can early emesis remove?
Up to 80%
What does productive emesis require?
The presence of food or liquid in the stomach
When should you induce emesis?
Most effective within 1 hour of ingestion
Useful up to 2 hours after ingestion
Unknown time of ingestion in an asymptomatic patient
When ingestion of a product known to stay in the stomach for a long time occurs
True of False: apomorphine is not recommended in cats, but it can be used in dogs
True
Why can apo be used in dogs?
CRTZ is largely controlled by dopamine receptors, so apo typically induces emesis
What should be used in cats to induce emesis and why?
Xylazine or dexmedetomadine because the CRTZ has alpha 2 receptors
When does emesis occur with apo?
Within 4-6 minutes
What can apo cause?
CNS depression
What is xylazine?
Centrally mediated α2-adrenergic agonist
What does xylazine use often result in?
Profound CNS and respiratory depression
What can CNS and respiratory depression be reversed by?
Atipamizle or yohimbine
What is used as an at home emetic?
3% hydrogen peroxide
True or False: hydrogen peroxide can be used in cats
False. It is not recommended because it can result in hypersalivation, hemorrhagic gastritis, protracted hematemesis
When is hydrogen peroxide more effective?
When a small amount of food is present in the stomach
When do you not want to induce emesis?
Depressed patients Decreased consciousness Seizures or are likely to seizure In symptomatic patients In patients with underlying disease predisposing them to aspiration pneumonia or complications associated with emesis induction
What are contraindicated toxins to using emesis?
Corrosive and caustic material
With hydrocarbon toxicant ingestion
Petroleum distillates
Other volatile materials that may result in aspiration pneumonia
What is multidose administration of activated charcoal indicated in?
Enterohepatic recirculation
Drugs with a long half-life
Delayed release products
True or False: additional doses of activated charcoal should contain cathartic.
False
What is activated charcoal relatively ineffective against?
Ethanol Methanol Isopropyl alcohol Acetone Petroleum distillates Pine oil Ammonia Xylitol Cyanide
What is activated charcoal dependent on?
Timing of administration
What is the benefit of multidose activated charcoal?
It has been found to significantly decrease the serum half-life of certain drugs
Why should cathatics no be used in additional doses of activated charcoal?
Increased risks for dehydration and secondary hypernatremia via fluid losses from the GI tract
What are contraindications for administration of activated charcoal?
Shock Dehydration Electrolyte disturbances Those with excessive free water loss Uncontrolled vomiting Caustic substance ingestion Compromised airway Neurologic deficits
What are cathartics designed to do?
Increase the speed and transit time of the GI tract
Promote fecal excretion of the toxin
What is the most commonly used cathartic? Why?
Sorbitol
Aids in the expulsion of the poison from the GIT
What are the side effects of sorbitol?
Vomiting Dehydration Secondary hypernatremia Abdominal cramping or pain Possible hypotension
What is cholestyramine?
Chloride salt of basic anion exchange resin that binds with bile acids in the intestines to prevent them from being reabsorbed
What should cholestyramine be used with?
Toxicants that undergo enterohepatic recirculation or biliary elimination
What are the indications for gastric lavage?
Toxicants that stay in the stomach for a long time or that form bezoars
Indications when emesis is contraindicated
Toxicants that have a very narrow margin of safety, result in severe clinical signs. approach 50% of the LD50
Where should the patient’s head be placed for gastric lavage?
Lower than the chest
What are indications for fluid therapy?
Excretion of the drug Aid in perfusion Prevent dehydration Encourage diuresis or nephrotoxins Treat underlying azotemia or electrolyte abnormalities Vasodilate renal vessels
What type of fluid is used for fluid therapy with toxicities that cause hypercalcemia?
Balanced crystalloid at 1.5 to 4 times the normal maintenance rate
What are colloid fluid therapies indicated in?
Low colloid oncotic pressure
Profound hyponatremia
Blood loss or acute hepatic insult
Whar are blood product therapies indicated in?
Anemia
Coagulopathy to anticoagulants or hepatoprotectants
What are examples of GI support?
Routine use of antiemetic therapy after emesis induction
Anti-emetics
H2 blocker
Proton pump inhibitors
What are toxicants that often result in CNS stimulation?
Amphetamines SSRI antidepressants Sleep aids Tremorgenic mycotoxins Rodenticides Methylxanthines 5-fluorouracil Insecticides
What are examples of neurologic support?
Sedatives to treat CNS stimulatory signs
Parenteral muscle relaxants
Phenobarnital
When tpxocants can have effects like CNS depression or sedation?
Muscle relaxants Sedatives Sleep aids Illicit drugs Marcocylic lactones
What is cerebral edema due to?
Primary toxicant
Secondary to uncontrolled, untreated seizures
What is used to treat increased intracranial pressure?
Mannitol
Hypertonic saline
What are examples of anxiolytics or sedatives?
Acepromazine
Butorphanol
What can be used as a reversal with opioid toxicity?
Naloxone
Butorphanol
What should be used with sleep aid toxicosis?
Flumazenil
What can alpha-agonist toxicity be reversed with?
Alpha-adrenergic antagonists (Yohimbine, Atipamezole)
What toxicities is S-adenosyl-methionine (SAM-e) used in?
Xylitol Blue-green algae NSAIDs Amanita mushrooms Acetaminophen Sago palm
What is N-acetylcysteine used for?
To limit the formation of NAPQI by providing alternate glutathione substrate with acetaminophen toxicosis
Has been anecdotally used for severe hepatotoxicity with sago palm and xylitol
What are beta blockers given for?
Severe tachycardia
What are beta blockers associated with?
SSRI, amphetamine, chocolate toxicosis
What is Vitamin K therapy used for?
Anticoagulant rodenticide toxicity
What is intravenous lipid emulsion therapy used for?
As an antidote for lipophilic drug toxicosis
How does IV lipid emulsion therapy work?
Lipid sink
Providing myocytes with energy substrates
Increasing the overall fatty acid pool
When is ILE advocated for use?
Macrocyclic lactones
Lidocaine
Pyrethrins
Calcium channel blockers
What does ILE have anecdotal success with?
Baclofen
Cholecalciferol
Beta blockers
Marijuana
What are the guidelines for ILE administration?
20% ILE bolus
Followed by CRI rate of 0.25 ml/kg/min IV over 30-60 minutes
Additional doses can be administered after 6-8 hours if signs have not resolved and serum is not lipemic
What are the possible complications with ILE therapy?
Fat embolism Fat overload syndrome Pancreatitis Worsening of acute respiratory distress syndrome Coagulopathy
