An Attack of the Vapours - occupational hazards of inhalational agents

Dr Phil Hodgson, Norwich, UK

The potential occupational health risks posed by inhaled anaesthetic agents have long been debated. Historically, their effects on the cognitive function, fertility and immune system of anaesthetists and theatre workers have all been well documented. However, with the advent of modern scavenging systems and the move towards intravenous techniques, it is assumed that there is no longer a significant risk of these effects occurring within the ranks of our profession. This assumption may be somewhat premature as there are some areas of anaesthetic practice where inhalational techniques, semi-open breathing systems and lack of ventilation still occasionally conspire to breach the legislated, maximal levels of occupational exposure. Furthermore, evidence is slowly emerging that even low, theoretically safe levels of occupational exposure may also cause measurable physiological, genetic and immunological changes in the anaesthetist. Therefore, the profession should be cautious and vigilant until any health consequences of such changes are fully established. 

Fortunately, health and safety legislation and the policing of occupational exposure both offer the individual some protection, but these vary considerably from country to country. This is far from ideal, but undoubtedly reflects the uncertainty and lack of evidence base as to where the safe level of exposure truly lies. Interestingly, The United Kingdom currently accepts levels of occupational exposure that would be considered unacceptable in most other EEA Countries and the USA.

The lecture will review the evidence base (if any) for the specific health risks said to be associated with passive inhalation of anaesthetic agents in the work-place. It will also focus on whether those that practise in higher risk areas (such as paediatric anaesthesia) put themselves at increased risk of such effects. Finally it will debate what level of protection and reassurance the current legislation offers to such individuals.

Although somewhat ‘preaching to the converted’ at this meeting, the lecture will undoubtedly provide a certain ‘feelgood factor’ to those who have largely abandoned inhalational techniques. It may also prove useful for persuading and/or scaring a few more ‘volatile’ colleagues into exploring TIVA and even joining the ranks of SIVA-UK (normal commission rates apply)!

Selected References:

1.        Occupational Exposure to Volatile Anaesthetics. Epidemiology and Approaches to Reducing the Problem. C Byhahn, H J Wilke, K Westphal. CNS Drugs 2001; 15: (3) 197-215.

2.        Risk of Spontaneous Abortion in Women Occupationally Exposed to Anaesthetic Gases: A Meta-analysis. J F Boivin. Occupational and Environmental Medicine. 1997; 54: 541-548.

3.        Genetic Damage in Operating Room Personnel Exposed to Isoflurane and Nitrous Oxide. K Hoerauf, M Lierz, G Weisner et Al. Occup Environ Med 1999; 56 ; 433-437.

4.        Autoantibodies Associated with Volatile Anaesthetic Hepatitis Found in the Sera of a Large Cohort of Pediatric Anesthesiologists. D Njoku, R Greenberg, M Bourdi et Al. Anesth Analg 2002; 94: 24-249

5.        Anaesthetic Agents: Controlling Exposure Under COSHH. Health and Safety Commission UK. HMSO 1995; ISBN 0-7176-1043-8.