1 / 16

Clinical Problem Solving in Poisoning 3

Clinical Problem Solving in Poisoning 3. Group F: Tse Ka Hei Tsui Tsz Kwan Wong Kin Wai Wong Sze Nga Yam Po Chu Patricia Yeung Yat Sing Kevin. Scenario. Retired executive Retrosternal chest pain 3-hr work in basement workshop

tosca
Download Presentation

Clinical Problem Solving in Poisoning 3

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. Clinical Problem Solving in Poisoning 3 Group F: Tse Ka Hei Tsui Tsz Kwan Wong Kin Wai Wong Sze Nga Yam Po Chu Patricia Yeung Yat Sing Kevin

  2. Scenario • Retired executive • Retrosternal chest pain • 3-hr work in basement workshop • Apply commercial paint & varnish remover to a wooden chest of drawers

  3. Scenario • On admission • On paint-remover label • 80% methylene chloride • Used only with adequate ventilation • Dx • Anterior wall myocardial infarction • Treat conservatively; D/C after 2 wks • Resume to work • Severe MI complicated by cardiogenic shock • Death after 2nd D/C

  4. Methylene chloride • Chemical name • Dichloromethane • Source • Solvents • Paint stripping products • Degreasers • Properties • Highly lipid-soluble • Volatile

  5. Methylene chloride • Toxicokinetics • Absorption: inhalation, dermal absorption • Metabolism: CYP450 (liver)  CO + CO2 • COHb level can be as high as 50% • Peak level may be delayed > 8 hrs

  6. What happened? CO poisoning

  7. What happened? • Carboxyhemoglobin • Affinity: CO >> O2 (250x) • Shift oxyHb dissociation curve to left •  oxygenation   CO  AMI

  8. What happened? • Carboxymyoglobin • Affinity: CO > O2 (60x) • Myocardial depression: dysrrhythmia, ischemia • Even in mild exposure • Pre-existing heart disease

  9. Any specific investigations? • Further questions in Hx before Ix • Prior Hx of cardiovascular disease  risk factors • Hx related to painting work • Duration • Frequency • Any other exposures to CH2Cl2 • Glues

  10. Any specific investigations? • COHb level • Normal level • Non-smoker: < 5% • Smoker: <12% • Only confirm CO poisoning • Not correlate w/ severity/ outcome • Redistribution of methylene chloride • Duration of exposure • Any previous prolonged treatment w/ oxygen

  11. Any specific investigations? • Formic acid in urine • Metabolite of CH2Cl2 • Direct measure CH2Cl2 • Air breathed out • Blood level

  12. Any specific investigations? • ABG • Confirm metabolic acidosis • Serious CO toxicity  worse Px • Oxygenation • Pulse oxymetry • Not reliable ∵ interference of COHb • Creatine kinase test • Rhabdomyolysis • Urine myoglobin • Rhabdomyolysis

  13. Any specific investigations? • LFT • Hepatotoxicity • RFT • Nephrotoxicity • Hypokalemia due to metabolic acidosis • Blood glucose • Esp. if altered mental status

  14. How to avoid tragedy? • Improve ventilation • Wear proper clothing • Avoid long term exposure • Avoid future exposure • Use alternative agent

  15. How to avoid tragedy? • 100% non-rebreather face mask • Promote cellular resp • Reduce elimination t1/2 of COHb • Continue until asymptomatic

  16. Reference • Ford: Clinical Toxicology, 1st ed., 2001 W.B. Saunders Company • Marx: Rosen’s Emergency Medicine: Concepts and Clinical Practice, 5th ed., 2002 Mosby • Agency for Toxic Substances and Disease Registry • http://www.atsdr.cdc.gov/tfacts14.html

More Related