Poisoning and Overdose Flashcards
What type of poisoning is the leading cause of death?
CO poisoning
What toxicity is the most common overdose?
Acetaminophen toxicity is the most common pharmaceutical agent causing fatalities
When should drug OD and poisoning be considered?
Diagnosis of drug OD or poisoning must be considered in ANY patient who presents w/ coma, seizure, acute hepatic or acute renal failure or acute bone marrow failure
What systems should be focused on in the PE?
1. Vitals & neurologic status A. Agitation, tremors, convulsions, coma 2. Pupil size 3. Skin A. Warm, dry skin B. Anticholinergics C. “Blind as a bat”, “hot as Hades”, “red as a beet”, “dry as a bone” & “mad as a hatter” D. Salivation & urination: Organophosphates 4. Abdomen A. Bowel activity
What treatments do all symptomatic OD pts need?
- Protection of airway
- IV access (2 lg bore)
- Supplemental oxygen to maintain SO2 > 95%
- Telemetry
- Continuous observation
What treatments do OD pts need if an altered mental status is present?
- D 50 1 ampule over 3-4 min
- Oxygen
- Naloxone/Narcan 2 mg IV push q 1-2 min up to 10-20 mg (pinpoint pupils)
A. Duration of action 2-3 hrs - Flumazenil/Romazicon 0.2 mg IV push q 30 sec x 2 doses, then 0.5 mg IV q min prn up to 6 doses (max 5 mg total) (nystagmus)
- Thiamine 100 mg IV or IM if alcoholism suspected
What other treatments may be considered in OD pts?
- Anti-seizure med
2. Decontamination
How is the airway supported in a pt with an altered mental status?
1. Establish airway A. No gag reflex /LOC-INTUBATE B. Supplemental O2 at 12L/min non-rebreather C. Monitor pulse oximetry continuously D. ABG’s
What type of OD increases the risk for pulmonary edema?
Salicylate OD
What IV meds may be given for an altered mental status pt?
- IV Access, large bore (18+ g or CVP)
A. Crystalloid (NS or LR)
B. Dopamine 5-15 ug/kg/min to maintain bp
How are seizures managed in an OD pt?
- Diazepam 0.1-0.2 mg/kg OR Lorazepam 0.05 mg/kg IVP, repeat in few min. x 1 prn
- If seizures continue, give Phenobarbital 20 mg/kg IV over 20 min
- Phenytoin ineffective for most poison induced seizures
How is gastric decontamination achieved in OD pts?
- NG tube & activated charcoal 1 g/kg in 1st hr
2. Gastric lavage
How is pulmonary decontamination achieved in OD pts?
- Fresh air/O2 via mask
2. Watch for delayed edema
How is ocular decontamination achieved in OD pts?
Irrigate w/ H2O or saline ONLY, STAT referral to Ophthalmology
How is dermatological decontamination achieved in OD pts?
- Remove clothes, avoid direct exposure
2. Wash
What methods are used to prevent absorption of toxins?
- Activated charcoal
- Gastric lavage
- Urinary alkalinization
- Hemodialysis
What is the mechanism of activated charcoal?
- Suspension in water with or without cathartic
2. Inhibits absorption of some toxins
What is the mechanism of gastric lavage?
- Gastric lavage w/ saline or tap water
A. Gastric irrigation or “pumping stomach”
What is the mechanism of urinary alkalinization?
Enhances elimination of some drugs
What dx studies are useful in a suspected OD/poisoning pt?
- CBC, CMP, serum osmolality, PT/PTT, ABG’s, carboxyhemoglobin, Urine tox screen, BAC, UA, serum drug levels
- CXR
A. R/O ARDS
B. Pulmonary Edema - EKG (serial if TCA’s)
- CT Brain w/o contrast if stuporous or comatose
What drug OD may cause hyperthermia?
- Amphetamine
- Anticholinergic
- Cocaine
- ETOH/Sedative Withdrawal
What drug OD may cause hypothermia?
- Ethanol
- Hypoglycemia
- Opioid
- Phenothiazine
A. Compazine
B. Thorazine - Sedative/Hypnotic
What drug OD can cause miosis?
- Cholinergic
- Opioid
- Sedative/hypnotic
What drug OD can cause mydriasis?
- Anoxia
- Anticholinergic
- Sympathomimetic
What drug OD can cause tachycardia?
- Amphetamines
- Anticholinergic
- Ethanol
- Nicotine
- Organophosphates
- ASA
What drug OD can cause bradycardia?
- B-Blocker
- Ca Channel Blockers
- Opioid
- Head Trauma
- Sedative/Hypnotics
What drug OD can Cause HTN?
- Amphetamine
- Cocaine
- Ergotamine
- Head Trauma
- MAOIs
- PCP
What drug OD can cause hypotension?
- B-Blockers
- Amanita Mushrooms
- Ca Channel Blockers
- Opioid
- TCA’s
- Sedative /Hypnotics
What drug OD can cause hyperventilation?
- ASA
- Sympathetic NS stimulants
- Alcohol withdrawal
What drug OD can cause hypoventilation?
- Opioid
- Ethanol
- Organophosphates
- Sedative/ hypnotics
What are the goals of drug OD/poisoning therapy?
- Support vital signs
- Prevention of further absorption
- Enhancement of elimination
- Administration of specific antidotes
- Prevention of re-exposure
- Tx is usually initiated before toxicology results & labs are known
What is the antidote for APAP OD?
Acetylcysteine (Mucomyst)
What is the antidote for anticholinergic OD?
Physostigmine
What is the antidote for organophosphate OD?
Atropine
What is the antidote for TCA OD?
Sodium bicarb
What is the antidote for benzodiazepines?
Flumazenil (Romazicon)
What is the antidote for CO OD?
100% O2
Hyperbaric chamber
What is the antidote for methanol OD?
Fomepizole
Ethanol
What is the antidote for narcotics OD?
Naloxone (Narcan)
What is the antidote for amphetamine OD?
None, supportive care only
What can ingestion of acids and alkalis lead to?
Tissue necrosis
What are the sxs of acid/alkali ingestion?
Mouth & throat pain, dysphagia, drooling, substernal or abd pain
How is ingestion of acid/alkalis treated?
- Includes diluting agent w/ water, milk or NS
- Endoscopy is recommended
A. Assess degree of damage
What are the sxs of inhalant OD?
Pt may have hallucinations & become abusive & combative
How is inhalant OD treated?
- ABC’s
- Supplemental oxygen, IV access, cardiac monitoring
- Protect airway
- Treat bronchospasm
A. (Inhaled albuterol)
What is the antidote for Methylene chloride?
100% oxygen
What is the antidote for alkyl nitrites?
Methylene blue
What is the antidote for carbon tetrachloride?
N-acetylcysteine (Mucomyst)
What are the sxs of anticholinergic OD?
- ↑ Temp
- ↑ HR
- ↑ BP
- Dilated pupils
- Lungs clear
- Absent BS
- Skin: Hot & Dry
What are the sxs of cholinergic OD?
- Normal Temp
- ↓ HR
- ↓ BP
- ↓ Resp
- Pupils constrict
- Lungs wet
- Hyperactive BS
- Skin Wet
What are the sxs of sympathomimetic OD?
- ↑ Temp
- ↑ HR
- ↑ BP
- ↑ Resp
- Dilated pupils
- Lungs clear
- Normal BS
- Skin: Hot & Wet
What are the sxs of opiate OD?
- ↓ Temp
- ↓ HR
- ↓ BP
- ↓ Resp
- Pinpoint pupils
- Lungs clear (If wet-ARDS)
- ↓ Bowel Sounds
- Skin: Cold & Dry
What are the sxs of sedatives/hypnotic OD?
- ↓ Temp
- ↓ HR
- ↓ BP
- ↓ Resp
- Nystagmus
- Lungs clear
- Normal BS
- Skin: Dry