More than 100 people were treated Monday for injuries caused by the wildfires that tore through Napa and Sonoma counties and forced the evacuation of two Santa Rosa hospitals.

With Kaiser Permanente and Sutter Health medical centers evacuated, the St. Joseph Health hospitals in the two counties took on much of the burden.

Santa Rosa Memorial Hospital’s emergency department treated about 90 patients for wildfire-related injuries, including 12 for burns that left them in critical condition, said Vanessa deGier, a spokeswoman for St. Joseph Health in Northern California.

Five were treated and released, while three remain in the intensive care unit and the medical-surgerical units, deGier said. Four patients were transferred to burn centers.

The majority of injuries were related to smoke inhalation. In total, Santa Rosa Memorial treated 160 people since midnight, and Chief Medical Officer Chad Krilich said the staff anticipates that number will climb to around 200 by end of day — a jump from the typical patient load of about 125 per day.

Santa Rosa Memorial also accepted a total of 12 transfers from Kaiser Permanente Santa Rosa and Sutter Medical Center — the six transfers from Sutter included several expectant mothers in active labor and newborns.

Queen of the Valley Medical Center in Napa treated a number of people for smoke inhalation, deGier said. The hospital saw 50 patients for wildfire-related injuries, with four patients treated and released for minor burns and a fifth who suffered “significant burns” transferred to a burn center.

Although Petaluma Valley Hospital did not receive any burn victims, hospital personnel treated 28 patients,including several who needed to be evacuated from Sutter Medical Center, Kaiser Santa Rosa and senior living facilities in the area.

The majority of patients sought care for smoke-related illnesses such as shortness of breath, dizziness, asthma and smoke inhalation, deGier said. Four patients were admitted to monitor their injuries and four patients were in active labor.

Chad Krilich, the chief medical officer at Santa Rosa Memorial, said many doctors who reported for duty Monday had lost their homes just hours before. The hospital was providing on-site accommodations for staff and volunteers who needed a place to sleep.

Krilich said he assumed his home was gone. He said he grabbed two photos — a picture of his wedding day and one of his children — five pairs of underwear and Hip Hop, the family’s aquatic turtle, before fleeing his Santa Rosa home about 2 a.m. and heading into work.

Vivian Ho and Marissa Lang are San Francisco Chronicle staff writers. Email: vho@sfchronicle.com, mlang@sfchronicle.com. Twitter: @VivianHo @Marissa_Jae