Wildfire smoke may impact anesthesia, surgical outcomes: Study

Pollutants absorbed into the body from wildfire smoke may affect the function of anesthesia and the outcome of surgery, particularly in children and other sensitive populations, researchers fear.

Wildfire smoke contains a mix of fine particles and chemicals, which collectively induce inflammation and decrease antioxidant levels, according to a special paper published in Anesthesiology on Tuesday.

Even in non-surgical settings, the authors noted, exposure to fine-particle pollution is known to play a role in cardiovascular events like heart attacks, rhythm abnormalities, heart failure and stroke.

Once inhaled, contaminants can enter the circulatory system and damage the heart, lungs and other organs, while also harming blood vessel linings, causing clotting abnormalities and activating platelets and inflammatory cells.

"Wildfire smoke causes inflammation and is known to worsen heart and lung disease and pregnancy outcomes," senior author Vijay Krishnamoorthy, chief of Duke University School of Medicine's Critical Care Medicine Division, said in a statement.

"At a time of rising global exposure, anesthesiologists need to be equipped to manage the potential adverse effects of wildfire smoke exposure on perioperative outcomes," he added.

The term "perioperative" generally refers to the time range from when surgical patients enter the hospital until they return home.

A long list of potential negative outcomes from wildfire smoke exposure could fuel "a greater burden of comorbidities" during that critical period, the authors noted.

"Wildfire smoke poses significant health risks, particularly in people with pre-existing heart and lung disease, obese patients, infants and young children and other vulnerable groups," Krishnamoorthy said.

Adverse respiratory outcomes affected 37 percent of children studied who had a prior history of related disease and underwent general anesthesia during healthy air periods, the paper stressed, citing recent research. 

But when looking at a population of children with such medical backgrounds under unhealthy air conditions, that figure surged to 55 percent, the researchers noted. 

"This finding may well represent just the tip of the iceberg, with wildfire smoke exposure being responsible for a significant perioperative morbidity burden," the authors stated.

While little is known about the specific pathways by which wildfire smoke exacerbates anesthesia and surgery risks, Krishnamoorthy and his colleagues are trying to help bridge that knowledge gap.

They are currently developing a mathematical model to improve their understanding of the effects of such exposures, with hopes of linking geographic smoke measurements to databases that include surgical outcomes.

Gaining this insight, the authors explained, could help anesthesiologists generate guidelines for assessing and managing risk that surgical patients might face amid wildfire smoke exposure.

For example, they added, the timing of a scheduled surgery could potentially be adjusted based on projected exposure levels.

"We hope our paper will inform anesthesia clinicians about the potential impact of wildfire smoke on patient outcomes," Krishnamoorthy said.

At the same time, he emphasized "the urgent need for information and action to better understand and manage these risks."