Hydrocarbons Hydrocarbons Organic compounds containing H and C

Hydrocarbons

Hydrocarbons Organic compounds containing H and C w Derived from plants or from petroleum distillates w 3 basic types w • aliphatic • aromatic • halogenated Petroleum distillates - produced from fractional distillation of crude petroleum w Terpenes - distillates of pinewood w

Hydrocarbons w w w AAPCC lists HC’s as the 12 th most common poison exposure 66, 645 cases of HC exposure in 1997, as reported by the American Association of Poison Control Centers 95% were unintentional, 60% were pediatric more than 1/2 of all exposures occur in children under the age of 6 years most exposures are accidental 20 people died in 1997, most in children > 5 yrs.

Hydrocarbons, cont. w Examples of petroleum distillates • • kerosene gasoline mineral spirits naphtha mineral seal oil diesel oil fuel oil

Hydrocarbons, cont. Characteristics that determine toxicity w surface tension - cohesiveness of molecules on the surface of a liquid w volatility - tendency of a liquid to change into a gas or vapor w viscosity - resistance of a substance to flow over a surface, directly relates to the aspiration hazard w • low verses high viscosity

Hydrocarbons, cont. Mechanism of toxicity, cont. w major threat is danger of aspiration pneumonitis w vomiting increases the risk of aspiration w when aspirated, petroleum distillates : • inhibit surfactant - causing alveolar collapse and resultant hypoxemia • can displace O 2 in alveoli - hypoxia • cause bronchospasm and capillary damage • cause hemorrhagic bronchitis • cause pulmonary edema

Hydrocarbons, cont. Mechanism of toxicity, cont. w Systemic toxicity can occur after oral ingestion • Most are lipophilic and attracted to the CNS causing CNS depression • Most cause direct mucosal irritation • Certain volatile agents (toluene, benzene, butane and xylene) have a disinhibiting euphoric effect • Can cause AV block, bradycardia

Hydrocarbons, cont. Characteristics of poisoning: w Signs and symptoms of pulmonary involvement w • • w coughing, gasping and choking smell of gasoline to the breath rales and wheezing upon auscultation hemoptysis and pulmonary edema Signs of CVS involvement: • Dyspnea, syncope, sudden cardiac death (sens. myocardium to catecholamines)

Hydrocarbons, cont. w Signs and symptoms of GIT involvement • irritation of oropharynx • nausea and vomiting • abdominal pain w Signs and symptoms of CNS involvement • • cerebral hypoxemia lethargy somnolence coma or seizures

Hydrocarbons, cont. w w w Management of poisoning Keep patient calm To induce vomiting or not to induce vomiting Do not induce vomiting in patients who have ingested low viscosity petroleum distillate hydrocarbons ingestion as it increases the risk of aspiration pneumonitis Do Maintain airway and support respiration

Hydrocarbons, cont. w Do induce vomiting in patients who have ingested: • • • halogenated hydrocarbons insecticides turpentine aromatic hydrocarbons or ones which contain of heavy metals - must protect airway (endotracheal intubation)

Hydrocarbons, Terpenes w w w Unsaturated aliphatic cyclic hydrocarbons derived from plants Includes pine oil, turpentine, and camphor oil 1998 AAPCC reported 10, 482 exposures to disinfectants containing pine oil, 1, 064 to turpentine, 8, 945 to camphor and 1, 237 to camphor/methyl salicylate. No fatalities were reported Most exposures are accidental

Hydrocarbons, Terpenes w Mechanism of Action • • • w all terpenes are local irritants GIT signs and symptoms aspiration pulmonary toxicity coma seizures Treatment: • Careful attention to airway • DO NOT induce vomiting because of initial risk of aspiration and risk of CNS depression or seizure