1 / 16

Inhalational injuries H.R.Sarreshtahdar , MD Occupational Medicine Specialist

Inhalational injuries H.R.Sarreshtahdar , MD Occupational Medicine Specialist. Irritant lung reactions. Many gases, fumes, and aerosols are directly toxic to the respiratory tract Site of effect is determined by: Water solubility High solubility (ammonia): irritation of upper respiratory

elaine
Télécharger la présentation

Inhalational injuries H.R.Sarreshtahdar , MD Occupational Medicine Specialist

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Inhalational injuries H.R.Sarreshtahdar, MD Occupational Medicine Specialist

  2. Irritant lung reactions • Many gases, fumes, and aerosols are directly toxic to the respiratory tract • Site of effect is determined by: • Water solubility • High solubility (ammonia): irritation of upper respiratory • Low solubility (O3): irritation of lower respiratory • Particle size • Large particles (>10μm): upper respiratory • Medium particles (3-10 μm): airways • Small particles (<3 μm): lung parenchyma

  3. Irritant lung reactions • Examples of some irritants: • Ammonia • HCl • SO2 • NOx • Phosgene • O3 • Clinical findings: • Immediate irritation of upper respiratory tract to late pneumonitis and pulmonary edema

  4. Management • Immediately obtain ABG + O2 therapy • Take a history (esp. attention to chemical asphyxiants) • Examine eyes, nose, pharynx for evidence of burns • Auscultate lungs • Baseline spirometry if subject is capable • Baseline CXray • Admit to hospital • Observe for 24-48h

  5. Simple Asphyxiants • Gases: • Methane, ethane, propane • Ethylene, propylene, acethylene • CO2 • N2 • NO • Effect: reduction of fractional inspiratory concentration of O2→ hypoxia • No toxic effects

  6. Simple Asphyxiants • Exposure: • typically in confined spaces (storage tanks, mines) • For gases heavier than air any low-lying semi-closed space with little air movement is dangerous Methane (mining) CO2 (food preservation, manufacture of dry ice,…) N2 (underwater work, mining, metallurgic operations, pressurizing oil wells)

  7. Simple Asphyxiants • Clinical findings: • Related on: • Asphyxiant concentration • Level of physical activity • Underlying medical status • Normal air O2: 21% • O2 (10-16%): tachycardia, tachypnea, exercise intolerance • O2 (6-10%): nausea, prostration, coma • O2 (<6%): rapid loss of consciousness

  8. Simple Asphyxiants Treatment • Immediate removal from exposure • Supportive measures (esp. supplemental O2)

  9. Toxic Asphyxiants Inhalation of asphyxiants which have toxicity to tissues • Carbon monoxide (CO) • Hydrogen cyanide (HCN) • Hydrogen sulfide (H2S)

  10. CO • An odorless, colorless gas • CO intoxication: the leading cause of death from gas inhalation • Exposure: • Incomplete combustion of fuels (vehicles, forklifts, generators, … esp. when used indoors) • Jobs: • Firefighters, petroleum refinery workers, furnace operators, …

  11. CO • Mechanism of action: • Binding to Hgb (COHb): • ↓ O2 binding capacity • Leftward shift of O2 dissociation curve • Binding to cytochrome oxidase: • Compromising cellular respiration • Clinical findings: • Headache, nausea, vomiting, malaise, loss of consciousness, coma, death, cardiac ischemia • Lab data: • ↑ COHb in cooximetry • Routine ABG is not helpful • EKG (MI without typical chest pain)

  12. CO Treatment • Immediate removal from exposure • 100% O2 • Hyperbaric oxygen

  13. HCN A colorless gas with bitter almond odor • Uses: • metal plating, and extraction of silver and gold salts from ores • Exposure: • thermolysis byproduct of many polymers • Jobs: • Pesticide workers, printing, soldering, firefighting, photography, paper production,… • Mechanism of action: • Binding to cytochrome oxidase • Clinical findings: • Dyspnea, dizziness, headache, confusion, loss of consciousness, coma, death

  14. HCN • Lab findings: • Blood cyanide level (not available) • Urine thiocyanate (not reliable) • Treatment: • Removal of exposure • Induction of metHgb (300 mg Na nitrite) • Detoxification of cyanide (sodium thiosulfate) • Supportive measures

  15. H2S A colorless gas with rotten egg odor • Exposure: • Many jobs (petroleum production and refinery, farming, chemical laboratory, excavators, fish processing, sewage workers,… • Mechanism of action: • Binding to cytochrome oxidase • Irritant effect on mucous membranes

  16. H2S • Clinical findings: • Irritant findings: airway irritation, burning eyes • Headache, dizziness, nausea and vomiting • Dermatitis, pneumonitis, pulmonary edema • loss of consciousness, coma, death • Lab data: • Blood sulfide level • Treatment: • Removal of exposure • Induction of metHgb (300 mg Na nitrite) • Supportive measures

More Related