Toxicology
- ETOH Intoxication
- Acetaminophen Overdose
- Salicylate Overdose
- TCA Overdose
- Cocaine Overdose
- Opiate Overdose
- Carbon Monoxide Inhalation
ETOH Intoxication
Management:
- Ensure airway, adequate respiratory drive, and management of secretions/emesis
- Thiamine, consider folate/MVI, D5NS (for volume and glycogen/NAD+ depletion - will not enhance elimination )
- Check FSBG. Hypoglycemia is caused by impaired gluconeogenesis in poorly nourished patients with depleted or low glycogen stores.
- Search for other causes if mental status not clearing in 3 to 4 hours.
- Alcoholic ketoacidosis: Volume repletion, thiamine, and supplemental glucose
- Start CIWA protocol for all suspected chronic alcoholics
Symptoms:
1. Tremulousness (6-12 hours after last drink)
- Pt irritable, hypervigilant, agitated. coarse tremor of hands and tongue
- Thiamine 100mg IV, MVI, Folate 1 mg IV/PO. Give thiamine before glucose
- Mg replacement, watch for drop in phosphate
- Valium 5-10 mg IV q5-10min until stops or Librium 25-100 mg PO hourly. Monitor closely for oversedation
2. Seizures
- If no past h/o seizure, work up to r/o head trauma, meningitis, brain abscess, etc.
- If past h/o EtOH seizure, treat as other seizures but loading with anticonvulsants not indicated
3. Delirium Tremens - autonomic instability with fluctuating mental status. 2-7 days after last drink, usually with visual hallucinations, perspiration, fever, tachycardia, hypertension. This is a medical emergency. mortality is approx. 5%
- Valium 5-10 mg IV every 5 to 10 minutes until appropriate sedation is achieved.
- Librium 25-100 mg PO at presentation, repeat as needed hourly. Monitor respirations.
- Thiamine, folate, MVI iv/po
- Replete Mg, K, Ca, PO4
- Rule out infection, pneumonia
- Admit to monitored setting
Other toxic alcohols:
- Send ethanol level to calculate corrected osmole gap in the case of suspected concurrent ethylene glycol or methanol ingestion.
- Toxic alcohol panel (ethylene glycol, methanol, isopropyl alcohol) can be sent but do not delay treatment if clinical suspicion is high.
- Most common differential diagnosis is alcoholic ketoacidosis, which can cause severe anion gap acidosis and moderate osmolar gap. Send a beta hydroxybutyrate level, which is more reliable than standard ketone test (acetoacetate).
References:
Kraut JA, Kurtz I. Toxic alcohol ingestions: Clinical features, diagnosis, and management. Clin J Am Soc Nephrol 2008 Jan;3(1!):208-25.
Goldfrank's Toxicology Emergencies, 9th ed 2010.
Poisoning and Drug overdose, 6th ed. 2012.
UpToDate. (2022). https://www.uptodate.com/contents/management-of-moderate-and-severe-alcohol-withdrawal-syndromes.
Acetaminophen Overdose
Check Acetaminophen levels and urine toxicology for co-ingestions
- Call poison control
- NGT, lavage with 2 L NS
- Activated charcoal: Give a single dose of activated charcoal at 1 g/kg p.o. via NG tube within 4 hours of ingestion
- N–Acetylcysteine: Passive given within 8 hours of ingestion and before ALT begins to rise, can give a charcoal
- Oral dosing of acetylcysteine: 140 mg/kg loading dose followed by 17 doses of 70 mg.kg every 4 hours. If patient vomits within 1 hour administration give full dose again
- Give acetylcysteine based on the nomogram. If unable to obtain level just treat.
- Follow acetaminophen levels q4h, LFT, PT/PTT
- Evaluate potential need for liver transplant; pH < 7.3, Cr > 3.4, INR >6.5
References:
1. Hospitalist Handbook, iPhone App
2. UpToDate -- Acetaminophen Overdose
3. NCBI
Salicylate Overdose
Check salicylate level and check urine toxicology for co-ingestions. Try to determine whether salicylate was regular or enteric-coated (Affects pharmacokinetics).
- Call poison control
- NGT, lavage with 2L NS
- Intubate for respiratory depression if indicated
- Activated charcoal, if indicated. 1g/kg po/per NGT q2-4h
- Alkalinize plasma/urine with a bolus of 1 to 2 Amps of sodium bicarb, then start 2 Amps of sodium bicarb per 1 L of D5 ¼ NS. Run this at approximately 4 mL/kg/hr. Do not use acetazolamide. Caution in elderly and renal failure as aspirin can cause pulmonary edema
- Replete potassium to maintain normal serum levels otherwise alkalinization will be difficult to achieve
- Be sure to treat concurrent hypoglycemia and coagulopathy if present
- External cooling if febrile (no acetaminophen)
- Hemodialysis indicated if level > 100mg/dL - level checked 6 hours after ingestion, refractory acidosis, persistent CNS symptoms, and/or if renal failure.
References:
1. Hospitalist Handbook, iPhone App
2.UpToDate -- Salicylate Toxicity
TCA Overdose
Call poison control.
- Check urine toxicology for co-ingestions esp. salicylates , acetaminophen.
- Get an EKG. Pay special attention to QRS, QTc, PR Beware QRS on EKG> 0.10 sec; VT, VF, myocardial depression can ensure (Q on T phenomenon)
- Evaluate if ICU admission is necessary: AMS, Respiratory depression, hypotension
- Telemetry
- If asymptomatic, get serial EKGs for 6 hours.
- NGT, lavage with 2 Liters NS, Ipecac contraindicated
- Activated charcoal 1g/kg within 2 hours of ingestion
- Alkalinize urine with 1NS & 2amps NaHCO3/I at 10-15 cc/kg/hr until urine output good, then D5W + 1-4 amps NaHCO3/I + 200 mEq KCl/I at 1-3x maintenance to give serum pH 7.5-7.55
- Do NOT use quinidine, procainamide if VT occurs. High risk for Torsades.
References:
1. Hospitalist Handbook, iPhone App
Cocaine Overdose
- Call Poison control
- ABCs, vital signs, Tele monitor
Diagnosis
- EKG, CXR, head CT if suspect cerebral hemorrhage.
- Labs: Urine toxicology, CBC, electrolytes, glucose, CPK, UA for myoglobin, lactic acid, Troponin, Pregnancy test.
Management
- For tachyarrhythmias, follow ACLS guidelines. Do best to avoid Beta-blocker but if needed, give IV esmolol.
- For HTN, give Benzodiazepine. If this does not work then consider Beta-blocker (esmolol), but never alone. Always give with either vasodilator (nitroprusside) or alpha blocker (phentolamine, intravenous (IV) bolus. The usual dose is 5 to 10 mg IV every 5 to 15 minutes as necessary.)
- For agitation and psychosis, Benzodiazepine(Diazepam be given in an initial dose of 10 mg IV, then 5 to 10 mg IV every 3 to 5 minutes until agitation is controlled), Haldol, chlorpromazine, or droperidol prn
- For seizures give diazepam (0.1-0.2 mg/kg IV q10-15 min for total of 30mg), but if status epilepticus, consider other causes such as continued drug absorption (broken bag of cocaine in GI tract)
- Decontaminate with gastric lavage, charcoal and cathartic if indicated.
- If need to intubate, avoid succinylcholine since this can cause further rhabdomyolysis
Source: Uptodate: Cocaine Overdose
Hospitalist Handbook
Opiate Overdose
Effects
- CNS - sedation and respiratory depression, seizures w/ meperidine, propoxyphene and dextromethorphan (Esp. in renal insult)
- Pulmonary - acute noncardiogenic pulmonary edema
Diagnosis
- H&P (pinpoint pupils, CNS and resp. depression)
- Response to naloxone
- Labs: urine tox (will not show fentanyl), CBC, eletrolytes, glucose, ABG, CXR, consider acetaminophen/ASA levels if combination drugs ingested
Treatment
- ABCs, oxygen
- Naloxone 0.2-2mg IV, may repeat dose q2-3 min up to total of 10-20mg IV. Necessary to monitor at least 3-4 hours after last naloxone dose which has half-life of 1 hour. Opiates have longer half life. Recommend 6-12 hour observation after opioid-induced coma and monitor for acute withdrawal syndrome in opiate dependent patients.
- If patient is intubated for airway protection/hypercarbia, naloxone is not necessary
- Decontaminate via gastric lavage, charcoal, cathartic.
Source: Uptodate: Opiate overdose
Carbon Monoxide Inhalation
Symptoms depend on CO level (carboxyhemoglobin)
- CO: 20-40%: Dizziness, headache, weakness, disturbed judgement, decreased visual acuity
- CO: 40-60%: Tachycardia, tachypnea, ataxia, syncope, seizures
- CO: >60%: Coma, death
Diagnosis
- To get CO level, get ABG with carboxyhemoglobin
- Standard pulse oximetry (SpO2) CANNOT screen for CO exposure, as it does not differentiate carboxyhemoglobin from oxyhemoglobin
- ECG, troponin if CO intoxication confirmed.
Management
- Treat with 100% O2 by tight-fitting mask or ET tube
- Intubation can be considered in severe cases (carboxyhemoglobin > 25%)
- Hyperbaric Oxygen if CO>25%
- Measure CO level q2-4h until <10%
- Must continue treating until carboxyhemoglobin is <5%
- Call Poison control
Source: Uptodate: CO poisoning