Calls and visits to Minnesota medical clinics increased midweek as people inhaling historically bad air could no longer tolerate it.
"You breathe the stuff in yesterday, and today stuff is flaring," said Dr. Andrew Stiehm, a pulmonologist with Allina Health in St. Paul.
Air quality levels in the Twin Cities nudged into the "very unhealthy" range at one point on Wednesday as smoke from Canadian wildfires blew south. Clinicians expected a delayed effect as the dirty air took its toll on patients with asthma, COPD and other breathing-related conditions.
Hospital emergency rooms didn't see a dramatic increase, though more than 30 patients came to Allina's two Mercy hospital campuses in Coon Rapids and Fridley with breathing-related problems on Wednesday.
Hennepin Health spokeswoman Christine Hill said she was personally "wheezing like crazy" but so far the downtown Minneapolis ER hadn't encountered a substantial increase in patients with conditions related to the air quality.
Organizations across Minnesota may have helped by taking the rare step of cancelling outdoor events in response to the air quality warnings. Youth soccer fields across the Twin Cities were deserted as teams and leagues cancelled practices and games.
Patients at greatest risk may have closely heeded the air quality warnings, especially after some days this spring when levels jumped to the unhealthy range, Stiehm said.
Anyone with long-term breathing issues experiencing symptoms that are "clearly worse" than expected should check in with their doctors, he said. For people with asthma, frequent "night awakenings" with flareups is one indicator. Blood oxygen readings of 92 or lower are another warning sign for people with chronic breathing problems.
"Particularly in the wake of COVID, a lot of people have their pulse oximeters," Stiehm said.