Evaluating MSDS First Aid Advice

Transcription

1 Evaluating MSDS First Aid Advice Senior Technical Specialist

2 Evidence-Based Approach Identify specific questions Search for relevant literature Critically evaluate quality of evidence Determine best answer

3 Specific Questions Routes of exposure Breadth of toxic effects Standard first aid practices

4 Literature Search Bibliographic databases Secondary sources Data mining

5 Literature Evaluation Human vs animal Controlled study vs case reports Quality of study design Other evidence-based reviews

6 Best Answer Clearly stated conclusions Supported by best evidence

7 All chemicals are not created equal

8 Today s Focus Present some key conclusions Examine some first aid advice from current MSDSs Answer your questions

9 Emergency Oxygen Historically, recommended for every chemical exposure Eventual concern that this practice could cause harm UK review (2001) American Heart Association review (2005)

10 Our Conclusion Emergency oxygen may be beneficial following exposure to a chemical that interferes with the body s ability to get enough oxygen to sustain life and health. Special training is required.

11 These are chemicals that: Displace oxygen in the air Interfere with oxygen crossing through lungs into the blood Impair the blood s ability to deliver oxygen to the cells Impair cell s use of oxygen

12 Neutralization Following Skin Contact Seems logical But: Availability of neutralizing agent? Thermal burns? Additional injury?

13 What the Science Shows Neutralization of 8% sodium hydroxide: 9% sodium citrate resulted in deeper injury 5% acetic acid resulted in: Shorter flushing time (15 vs 32 min) Less severe tissue injury at 24 hr Outcome similar to water complete healing at 14 days

14 Conclusion There is no clear benefit to neutralizing agents instead of water following skin contact with acidic or basic chemicals.

15 Duration of Water Flushing Standard minutes But, not all chemicals are the same: Non-irritants to mild irritants Moderate to severe irritants Corrosives

16 What the Science Shows Skin contact with 8% sodium hydroxide 32 or 60 minutes for ph to return to normal when flushing begun within one minute 90 minutes with a 10 minute delay

17 Skin contact with 3.65% hydrochloric acid: 10 minutes for ph to return to normal when flushing begun within 1 minute ph did not return to normal even after 60 minutes of flushing if 3 or 10 minute delay BUT, statistical significant improvement in ph from 8-25 minutes

18 Eye Contact Severe eye damage observed even with immediate first aid; flushing duration less than 30 minutes. Eyes with prolonged irrigation (1-2 hours): Less damage Better visual outcome Shorter hospital stay Earlier return to work

19 Our Conclusions Flushing MUST start immediately Longer flushing for corrosives: 60 minutes for strong alkalis; 30 minutes for other corrosives minutes good for moderate to severe irritants 5-minutes for non-irritants to mild irritants

20 Removal of Clothing Personal embarrassment aside start stripping right away! Estimate contamination reduced by 75-90%

21 Inducing Vomiting Some researchers have shown benefit if stomach emptied with one hour of ingestion Others have shown NO benefit

22 What We Do Know The following factors must be carefully considered: High degree of risk or evidence of toxicity Time since ingested If vomiting has already occurred

23 Our Conclusion MSDSs should not recommend inducing vomiting Call Poison Control Centre for advice

24 Syrup of Ipecac Causes vomiting Several evidence-based reviews have concluded that it should not be routinely administered even at ER

25 Activated Charcoal Evidence based review concludes: should not be used in routine management of poisoned patients may be used on advice of Poison Control Centre or at ER

26 Water or Milk? Some animal studies suggest that dilution with water or milk may be beneficial BUT - No human evidence Large volumes of water can actually increase toxicity of some chemicals

27 Some Poison Control Centres recommend taking small sips of water. Others advise that nothing should be taken by mouth without the specific advice of a Poison Control Centre.

28 An evidence-based review by American Heart Association concluded that nothing should be given by mouth without the advice of a Poison Control Centre.

29 Our Conclusion A small amount of water may be beneficial but it is best done with the advice of a Poison Control Centre.

30 Some Real Examples

31 Drain Cleaner (strong alkali) Skin/Eyes: Flush area with water for 15 minutes. Our Advice: 60 minutes Ingestion: Do not induce vomiting. Give milk, egg white, gelating sol or water. Our Advice: Immediately call the Poison Control Centre.

32 Non-Toxic Alcohol Inhalation: Using proper respiratory protection, immediately remove the affected victim from exposure. Administer artificial respiration if breathing is stopped. Keep at rest. Call for prompt medical attention. Our Advice: If symptoms develop, remove source of contamination or move victim to fresh air. If symptoms persist, obtain medical advice.

33 Same Non-Toxic Chemical Ingestion: Do not give liquids if victim is unconscious or very drowsy. Otherwise, give no more than 2 glasses of water and induce vomiting by giving 30 cc (2 tbsp) syrup of ipecac. If ipecac is not available, give 2 glasses of water and induce vomiting by touching finger to back of victim's throat. Keep victim's head below hips while vomiting. Our Advice: If irritation or discomfort occur, obtain medical advice.

34 Low Toxicity Liquid Ingestion: Do not induce vomiting. Administer 2-3 tbsp of activated charcoal with large amounts of vegetable oil, milk or water. Burnt toast can be used if charcoal is unavailable. Obtain medical assistance immediately. Our Advice: Activated charcoal should only be given on advice of Poison Control Centre. No evidence to support efficacy of burnt toast.

35 Hydrofluoric Acid Skin Contact: immerse the burned area in iced 0.13% benzalkonium chloride (Zephiran ) solution. If immersion is not practical, towels should be soaked with the above solutions and used as compresses for the burn area. Hydrofluoric acid can cause devastating skin injuries and death. Special first aid procedures, like these recommendations, are scientifically proven.

36 Some Parting Words Familiarize yourself with current best practices Understand the health hazards of the product Ask questions

37 The Material Safety Data Sheet A Practical Guide to First Aid Available at: