Electronic cigarettes

Background

• Nicotine containing products that are currently not regulated by the FDA
• On 4/25/14, the FDA proposed legislation to allow them to regulate e-cigarettes like other tobacco products
• Nicotine usually suspended in a propylene glycol or vegetable glycerin solution (labeled as %PG/%VG)
• Increasing toxic exposure to e-cigarettes
• From Sept 2010 - Feb 2014, there were 16,248 toxic exposures to traditional cigarettes and 2,405 toxic exposures to e-cigarettes
• Exposures to e-cigarettes increased from 1/month to 215/month over that time period

Product Types

• • Some are fixed products with no refill capabilities (Ex. Blu e-cigarettes) while others can be refilled with replacement nicotine fluid
• Common strengths include 6mg/ml (low), 12mg/ml (medium-low), 18mg/ml (medium), 24mg/ml (high) and 36mg/ml (Ultra-high)
• Common refill sizes range from 5ml to 30ml
• Products come in a variety of flavors that can be enticing to children
• Bubble gum, root beer, extreme soda, Ecto-cooler, Banana cream pie, toasted marshmallow, etc.

Pathophysiology

• Fatal intoxications are rare and estimates suggest 60mg as a lethal dose. Traditional cigarettes deliver approximately 2mg of icotine

Absorption

• • Absorbed transdermally, orally and via inhalation

Biphasic presentation

• • Initially excitation secondary to excitation of the presynaptic nAChR which facilitates release of neurotransmitters
  • Second phase characterized by desensitization of the receptors and decreased neurotransmitter release

Clinical Features

• Highly variable presentation
  • Tobacco is a GI irritant and often causes spontaneous vomiting
  • Biphasic presentation
    • Initially present with excitation, N/V/D, salivation, tachycardia, hypertension, diaphoresis
    • Delayed presentation is hypotension, bradycardia, hypoventilation, fasiculations, seizures, coma, death

Diagnosis

• Exposure to nicotine containing liquid
• Toxidrome similar to nicotinism

Work-Up

• CBC
• Chem 7
• Utox

DDx

• Anticholinergic toxicity

Treatment

• Consider GI decon with Activated Charcoal if patient presents <2 hours after ingestion and remains cooperative

Sedation

• Decreases the risk of hyperthermia, rhabdo, traumatic injuries
• Benzos are agents of choice especially increase seizure threshold
  • Repeat boluses every 5-15 minutes as needed to halt seizures and provide adequate sedation
  • Goal: QRS duration < 110 msec

Cholinesterase inhibition

• Indicated for severe agitation or delirium (esp if unresponsive to benzos)
• Contraindicated in QRS>100 or Na blockade signs (R' in aVR) and in narrow angle glaucoma
• Relatively contraindicated in asthma or ileus
• Physostigmine - strongly consider poison control consult before giving
  • Crosses blood brain barrier, can be used to help make dx
  • Dosing: 0.5mg-1mg IV over 5min (repeat dosing up to 2mg in first hour)
  • Onset of action: 5-10min
  • If partial response, repeat x3
  • If 3 or more administrations are needed over a 6-hour period, start IV infusion (bolus 1-2 mg followed by 1 mg/hour)
  • Stop infusion every 12 hours to determine resolution of the toxidrome
  • Side effects: bradycardia, dysrhythmias, cholinergic excess
  • Always have atropine at the bedside for bradycardia or cholinergic excess</ref>
  • Contraindicated in TCA toxicity (associated with cardiac arrest) and in the presence of bradycardia or AV block

Other therapies

• Sodium bicarbonate for conduction abnormalities (QRS prolongation)
  • 2 mEq/kg bolus (typically 2-3 amps of bicarb)
  • Begin continuous NaCO3 infusion at 250mL/hr if bolus effective
  • Solution preparation = 1L D5W mixed with 3 ampules NaHCO3

Disposition

• Admit for symptomatic poisonings

Source

• http://www.bestecig.com/help.asp?id=57
• https://s3.amazonaws.com/public-inspection.federalregister.gov/2014-09491.pdf