Title 14. HYDROCARBONS PETROLEUM PRODUCTS AND PEG.pdf ✅

PHARMD GURU Page 1 HYDROCARBONS: PETROLEUM PRODUCTS INTRODUCTION: Traditionally, the term hydrocarbon have been used to represent compounds derived from petroleum distillation, and hence were considered synonymous with petroleum distillates. But this is incorrect since the term should (logically) cover all organic compounds made of predominantly carbon and hydrogen molecules. The number of carbon molecules can vary from 1 to 60. In general, compounds which contain 1 to 4 carbon molecules are gaseous, while those which have 5 to 19 are liquids, and compounds with more than 20 are solids. 1. Aliphatic Hydrocarbons (Paraffins): These comprise compounds with saturated molecules (containing no carbon-carbon double or triple bonds) which have straight or branched-chain arrangements. Common examples include butane, ethane, methane, and propane (gaseous) ; benzine, gasoline or petrol, diesel oil, kerosene, mineral seal oil, lubricating oil or mineral oil, and turpentine or pine oil (liquids) ; paraffin wax, petroleum jelly or vaseline, grease, tar, and asphalt (semi-liquids or solids). 2. Aromatic Hydrocarbons: They contain at least one benzene ring and are unsaturated compounds. Common examples include benzene, toluene, xylene, styrene and naphthalene. 3. Halogenated Hydrocarbons: Most of these are clear, colourless liquids which have a chloroform-like odour. Common examples include carbon tetrachloride, ethylene dibromide, ethylene dichloride, dichloroethylene, trichloroethylene, methylene chloride, propylene chloride, chloroform, methyl chloroform, methyl bromide, fluorocarbons and organochlorine insecticides. 4. Cycloparaffins (Naphthenes): They are saturated hydrogen compounds which are arranged in closed rings. Common examples include cyclohexane and methylcyclopentane. HYDROCARBONS: PETROLEUM PRODUCTS AND PEG
PHARMD GURU Page 2 5. Alkenes (Olefins): These compounds contain one carbon-carbon double bond in the molecule. They are mostly used in the manufacture of other hydrocarbon products such as halogenated hydrocarbons. USES:  Butane, propane, Diesel oil, Gasoline (Petrol), Kerosene are used as fuel.  Benzine is used as solvent.  Mineral seal oil is used as Furniture polish.  Turpentine is used as Paint thinner, paint remover. MECHANISM:  Major threat is danger of aspiration pneumonitis. Vomiting increases the risk of aspiration. When aspirated, petroleum distillates inhibit surfactant - causing alveolar collapse and resultant hypoxemia. They can displace 02 in alveoli hypoxia bronchospasm and capillary damage. They also cause hemorrhagic bronchitis and pulmonary edema.  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. CLINICAL (TOXIC) SYMPTOMS:  After ingestion of even a very small amount of liquid hydrocarbon, patients initially cough, choke, and may vomit. Young children may have cyanosis, hold their breath, and cough persistently. Older children and adults may report burning in the stomach.  Aspiration pneumonitis causes hypoxia and respiratory distress. Symptoms and signs of pneumonitis may develop a few hours before infiltrates are visible on x-ray. Substantial systemic absorption. Particularly of a halogenated hydrocarbon. may cause lethargy, coma, and seizures. Nonfatal pneumonitis usually resolves in about 1 wk: mineral or lamp oil ingestion usually resolves in 5 to 6 wk.
PHARMD GURU Page 3  Arrhythmias usually occur before presentation and are unlikely to recur after presentation unless patients have excessive agitation.  Acute exposure can cause dermatitis, and if this is prolonged it may result in full thickness burns. Chronic exposure to kerosene can cause severe acne. Contact with liquefied petroleum gases (e.g. propane, butane. propylene. isobutane, butenes, n- butane), ethane, etc. can result in frostbite or effects resembling frostbite.  Disseminated intravascular coagulation, haemolytic anaemia and pancytopenia have occasionally been reported following vapour inhalation, aspiration, or ingestion of hydrocarbons.  Chronic exposure to some hydrocarbons can result in aplastic anaemia, hepatic necrosis, and jaundice. Hydrocarbons exposure has been associated with laryngeal and intestinal carcinoma. INVESTIGATIONS/DIAGNOSIS:  Chest x-ray and oximetry done about 6 hrs after ingestion  If patients are too obtunded to provide a history, hydrocarbon exposure may be suspected if their breath or clothing has an odor or if a container is found near them. Paint residue on the hands or around the mouth may suggest recent paint sniffing.  Obtain baseline CBC, Electrolytes, glucose-6-phosphate dehydrogenase level, liver enzymes and renal function tests, urinalysis and urine dipstick test for haemoglobinuria.  Measurement of urinary metabolites may help to confirm the diagnosis.  Diagnosis of aspiration pneumonitis is by symptoms and signs as well as by chest x- ray and oximetry. Which are done about 6hrs after ingestion or sooner if symptoms are severe. If respiratory failure is suspected, ABGs are measured.  CNS toxicity is diagnosed by neurologic examination and MRI.
PHARMD GURU Page 4 MANAGEMENT:  Consider pre-hospital administration of patients with a potentially toxic ingestion who are awake and able to protect their airway.  No specific antidotes are available for hydrocarbon poisoning. Treatment with corticosteroids and prophylactic antibiotics is not beneficial. In some cases. Steroids may be harmful.  Consider gastric lavage with a large-bore orogastric tube after a potentially life- threatening ingestion if it can be performed soon after ingestion (generally within 60 minutes).  Remove contaminated clothing and wash exposed area extremely thoroughly with soap and water.  Treat renal failure with dialysis and hepatic failure with fresh frozen plasma, vitamin- K, low-protein diet, neomycin and lactulose. HYDROCARBONS: PEG Polyethylene glycol (PEG) is a colorless, odorless, sweet-tasting chemical. It is poisonous if swallowed. PEG may be swallowed accidentally, or it may be taken deliberately in a suicide attempt. PEG has been widely applied in various medical fields due to its outstanding properties such as satisfactory safety, biocompatibility, hydrophilicity etc. Although PEG is normally considered as almost non-toxic, some unsafe problems of PEG with low molecular weights have been noticed by researchers. USES:  Polyethylene glycol (PEG) has pharmaceutical and industrial uses. Pharmaceutical uses include cleansing the colon prior to gastrointestinal examination or surgery and for the treatment of constipation.  Industrial uses include lubrication for textile fibers, rubber molds, and metal-forming operations, as well as in water paints, paper coatings, and polishes, and in the ceramics industry.