Sevoflurane and occupational exposure

[Micaela Notarangelo]

I have been asked about the safety of breastfeeding a 12 moths old infant while being exposed, for professional reasons (operating theater nurse), to sevoflurane. I have checked MMM 2014 and some literature about occupational and long term exposure, but got no clear answer. I understand that there aren't studies about this and thus no solid data, but I would very much appreciate an evaluation of the risks for the child.
Thank you in advance,
Micaela

[admin-james]

Hi, thanks for your post.

Sevoflurane has become popular because of its rapid washout from the body. Our recommendation for patients undergoing a procedure is that breastfeeding is safe enough about an hour after the resolution of anesthesia.

If you are practicing in the US, occupational exposure is regulated by OSHA guidelines. OSHA says of sevoflurane: "Since there are limited data, occupational exposure limits for these agents have not been determined." However, they also say that engineering controls that reduce one halogenated anesthetic gas in the air will effectively reduce all of them.

Once babies are older than about 9 months, the risks of drug exposure via breastmilk decline sharply. They consume much less breastmilk relative to their body weight than neonates and their ability to process drugs is often close to that of adults.

Please call us at the InfantRisk Center if this has not completely answered your question. (806)352-2519

-James Abbey, MD
and
-Thomas W. Hale, Ph.D.

The following references may be useful to you:

https://www.osha.gov/dts/osta/anestheticgases/index.html#C2

[Micaela Notarangelo]

Thank you.
We are in Italy, but occupational exposure limits are not defined here as well, as far as I understand.

What I would like to know is if, in your evaluation (I understand that there are no data), the little % of sevoflurane that goes to the fat compartment and the one that is metabolized through plasma, could theoretically pose a relevant risk to the baby in case of long term exposure of the mother. My understanding is that these % are probably low enough to be negligible through breastmilk, even if half-life for these are rather long, but I am not sure of myself.

Thanks again.
Micaela

[admin-james]

The manufacturer cites a safety study done on dogs to argue that long-term exposure to sevoflurane does not produce clinically relevant harm. In this study, dogs were exposed "to sevoflurane for 3 hours/day, 5 days/week for 2 weeks (total 30 hours exposure) at a flow rate of 500 mL/min in a semiclosed, rebreathing system with soda lime. Renal toxicity was not observed in the study evaluation of clinical signs, hematology, serum chemistry, urinalysis, or gross or microscopic pathology."

It is our opinion that nominal occupational exposure does not pose a risk to the breastfeeding infant.

-James Abbey, MD
and
-Thomas W. Hale, Ph.D.