Wildfire smoke and anesthesia
Myron Yaster MD
As I look out my window this morning, I can’t see the majestic Rockie mountains because the once crystal clear air and blue sky of Denver is now enveloped in smoke and haze from the wildfires in California, Oregon, and Colorado. And just think about it, this smoke has traveled an incredible distance…hundreds, if not thousands of miles away. Although once a rare event, because of global warming and forest mismanagement, these fires are now commonplace and more severe than ever before. Today’s PAAD by Hughes et al.1 reviews the impact of wildfire smoke on acute illness (and anesthesia). Myron Yaster MD
Original article
Hughes F, Parsons L, Levy JH, Shindell D, Alhanti B, Ohnuma T, Kasibhatla P, Montgomery H, Krishnamoorthy V. Impact of Wildfire Smoke on Acute Illness. Anesthesiology. 2024 Oct 1;141(4):779-789. doi: 10.1097/ALN.0000000000005115. PMID: 39105660.
Wildfire smoke (and air pollution) affects almost every organ in the body and impacts health, disease, and anesthetic care (figure). “Air pollution from combustion contains fine particulate matter (PM) that is typically composed of carbon, sulfur, and nitrogen compounds. Exposure to this PM causes more death and disability worldwide than alcohol use, high-sodium diets, or fasting hyperglycemia.2 Consequently, the World Health Organization (Geneva, Switzerland) recommends that exposure to mean 24-h concentrations of PM with a diameter of 2.5 μm or less (PM2.5) not exceed 25 μg/m3. Wildfire smoke composition is influenced by the fire area, intensity, and materials burned. In addition to PM, it contains gases, including carbon dioxide, sulfur dioxide, nitric oxide, ozone, polycyclic aromatic hydrocarbons, and volatile organic compounds (e.g., aldehydes and alkanes).3 The latter elements may make wildfire smoke inhalation even more harmful than fossil fuel–derived PM. Further, polyaromatic hydrocarbon components may be carcinogenic in the long term.4”1
Hughes et al. review the myriad effects of wildfire smoke on human health which they concisely and beautifully summarize in the figure above. I like many of you knew of these effects on respiratory disease and function and on obstetric and preterm birth risk, but didn’t realize the profound effects on inflammation, oxidative stress and on the cardiovascular system. For a deeper dive beyond the figure summary, I would urge you to take a few moments to read this article in its entirety.
“Children are particularly vulnerable to PM pollution due to increased minute ventilation relative to body mass and reduced efficiency of nasopharyngeal particle deposition. This unique physiology results in a higher proportion of particles reaching lung tissues.5 Since the mid-1990s, pediatric asthma presentations have been shown to increase during wildfire smoke exposure.6 Furthermore, fire-derived ozone emissions account for more than 2,000 annual pediatric emergency department visits for asthma in the United States.7”1
We’ve argued for decades about the effects of URIs on asthma and other perioperative airway events, when to delay or reschedule surgery, etc. Clearly, smoking in the household is a well known risk factor. 8,9 Shouldn’t we add woodfires to this list?
Send your thoughts and comments to Myron who will post in a Friday reader response.
References
1. Hughes F, Parsons L, Levy JH, et al. Impact of Wildfire Smoke on Acute Illness. Anesthesiology 2024;141(4):779-789. DOI: 10.1097/aln.0000000000005115.
2. Lim SS, Vos T, Flaxman AD, et al. A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet (London, England) 2012;380(9859):2224-60. (In eng). DOI: 10.1016/s0140-6736(12)61766-8.
3. Le GE, Breysse PN, McDermott A, et al. Canadian Forest Fires and the Effects of Long-Range Transboundary Air Pollution on Hospitalizations among the Elderly. ISPRS Int J Geoinf 2014;3(2):713-731. (In eng). DOI: 10.3390/ijgi3020713.
4. Black C, Tesfaigzi Y, Bassein JA, Miller LA. Wildfire smoke exposure and human health: Significant gaps in research for a growing public health issue. Environ Toxicol Pharmacol 2017;55:186-195. (In eng). DOI: 10.1016/j.etap.2017.08.022.
5. Bennett WD, Zeman KL, Jarabek AM. Nasal contribution to breathing and fine particle deposition in children versus adults. J Toxicol Environ Health A 2008;71(3):227-37. (In eng). DOI: 10.1080/15287390701598200.
6. Chew FT, Ooi BC, Hui JK, Saharom R, Goh DY, Lee BW. Singapore's haze and acute asthma in children. Lancet (London, England) 1995;346(8987):1427. (In eng). DOI: 10.1016/s0140-6736(95)92443-4.
7. Pratt JR, Gan RW, Ford B, et al. A national burden assessment of estimated pediatric asthma emergency department visits that may be attributed to elevated ozone levels associated with the presence of smoke. Environ Monit Assess 2019;191(Suppl 2):269. (In eng). DOI: 10.1007/s10661-019-7420-5.
8. Tait AR, Voepel-Lewis T, Malviya S. Perioperative considerations for the child with an upper respiratory tract infection. JPerianesthNurs 2000;15(6):392-396.
9. Tait AR, Reynolds PI, Gutstein HB. Factors that influence an anesthesiologist's decision to cancel elective surgery for the child with an upper respiratory tract infection. JClinAnesth 1995;7(6):491-499.