In Phoenix heat, ice-filled body bags are a life-saving technology

By Zahra Hirji, Bloomberg News

As temperatures hit 119 degrees in Phoenix last week, doctors at Valleywise Health Medical Center saw a patient whose internal temperature was at least 110 — the maximum registered by its thermometers.

Needing to cool the patient down as quickly as possible, the emergency medical team turned to a technique they had designed and honed themselves: immersing the person in a body bag filled with ice. It worked. In less than half an hour, the patient’s temperature was down to about 102, low enough to move on to further treatment and observation. The next day, the medical team had to pull out a new body bag.

All over the world, this July has been record-setting hot — the result of an intensifying El Niño in the Pacific Ocean layered on top of a worsening climate change. The impacts are especially severe in Phoenix, ground zero for extreme heat in the U.S. The city has experienced 25 consecutive days with temperatures of at least 110, a record. At night, temperatures have hovered in the 90s.

“Even for us locals, it’s just too hot,” says Geoff Comp, an emergency doctor at Valleywise and a Phoenix native. The heat’s impact is “scary,” he says. “People are getting really, really sick.”

In July, the two Valleywise hospitals in Phoenix have treated patients for heat illness on a daily basis, Comp says. In Maricopa County, which includes Phoenix, officials have confirmed 18 heat-related deaths this year and are investigating 69 more.

“This is a problem every summer for us,” says Nick Staab, medical epidemiologist at the Maricopa County Department of Health. “Over the last couple of years, we’re just seen a consistent increase in the number of heat-related deaths. In 2022, we saw 425 deaths, and that was a 25% increase over 2021.”

For years, the Valleywise emergency medical team treated patients suffering from heat illness using what’s known as “evaporative cooling.” That could mean spraying a patient with water while a fan blows on them, for example. “It works but it’s not really efficient,” Comp says.

The hospital’s staff and students wanted to find a better way — and felt they needed to, given Phoenix’s propensity for extreme heat and the vulnerability of some parts of its population. Many of those who come into the hospital with heat stroke are also suffering from substance abuse.