Talking with U of M

Talking extreme heat with the U of M

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With summer in full swing, extreme heat is following closely behind. As hospitalization visits increase, it is important to be aware of the dangers and preventative measures you can take to stay safe in increasing temperatures.

Vishnu Laalitha Surapaneni, MBBS, MPH, with the University of Minnesota Medical School and M Health Fairview, discusses extreme heat and the effect it can have on Minnesotans.

Q: What are the effects of extreme heat?

Surapaneni: Extreme summer heat can affect our health in many ways. Direct effects include heat cramps, heat exhaustion and heatstroke, which can be fatal. Symptoms start with prolonged exposure to extreme heat — being outdoors or staying inside homes with limited ventilation and air conditioning. The risk is increased with physical activity and limited hydration. Symptoms can include headaches, body aches, nausea, dizziness — and in more severe cases — confusion and high body temperatures of over 103 degrees Fahrenheit. There are also more complex ways heat can affect us. For example, heat worsens air quality, which leads to ER visits and hospitalizations for asthma attacks and heart attacks.

Q: Who is at the most risk?

Surapaneni: Everyone is at risk, but some groups are more vulnerable than others. People who are more exposed to extreme heat in their daily lives are at the most risk. This includes outdoor workers — think farmers, construction and delivery workers, athletes, and those lacking in housing. In addition, older people, pregnant women and young children are less able to regulate their body temperature and are at higher risk for heat-related illness. Minnesotans who have health conditions like heart failure, asthma or kidney disease — and especially those taking medications for these conditions — are more likely to suffer dehydration or heat stroke. 

Q: How can heat affect air pollution, and in turn, how can that air pollution affect us?

Surapaneni: On hot days, air stagnates. Despite having overall good air quality in Minnesota, our air still has pollutants like particulate matter and volatile organic compounds that are released from tailpipes, homes and industrial locations. These pollutants essentially bake in the heat and create new air pollutants like ground-level ozone that are harmful to our health. Unhealthy air levels of ground-level ozone hurt our respiratory and heart health and trigger asthma attacks.

Q: What preventative measures can be taken against extreme heat?

Surapaneni: Step one is to recognize that extreme heat, made more likely by climate change, is a public health issue in Minnesota. And, as Minnesotans who live in a traditionally cooler region, we are more likely to suffer heat-related illness at a lower heat index (temperature and humidity). The heat index for hospitalization related to extreme heat is around 86 degrees Fahrenheit in the Midwest. Step two is to limit exposure. In the spring and summer, be aware of alerts for extreme heat in your area and stay indoors or in areas with air conditioning. When you do go outside, have a heat plan. It is imperative to stay hydrated, so bring water along with you. Take breaks if you are doing intensive physical activities. 

This advice will not work for everyone, which is why we need system changes. This could be in the form of making sure your child’s school has a heat plan or establishing a neighborhood watch to ensure elderly neighbors limit their time outdoors and have access to air conditioning. It also means state and city policies like workplace regulations to ensure workers are protected from excess heat and developing climate adaptation infrastructure like cooling centers for high-risk communities. The bottom line is that extreme heat is something we cannot afford to avoid completely. It’s time we start planning to avoid the health impacts.

Q: What should healthcare providers be aware of?

Surapaneni: Our patients are already suffering the health impacts of extreme heat and this is projected to worsen with climate change. As healthcare providers, first, we need to educate ourselves on the myriad ways that extreme heat can bring patients to our emergency rooms and clinics. It’s not just dehydration and heat strokes. Extreme heat can show up as kidney injury, heart failure, asthma attacks or an altered mental state. These risks are especially greater for patients who live in urban heat islands and those who lack stable housing. In our clinical encounters, we can prevent these effects by screening our patients who are at high-risk for extreme heat and working with insurance companies and utilities to get them access to air conditioning. We need to work with our healthcare institutions to designate building spaces as community cooling centers. We must advocate for our elected officials to design policies that enable our communities to adapt to extreme heat, such as urban greening, access to clean renewable energy and urban cooling centers.

Vishnu Laalitha Surapaneni, MBBS, MPH, is an assistant professor at the Medical School and a hospitalist at the M Health Fairview University of Minnesota Medical Center. She specializes in climate change and its impact on human health. Surapaneni works with community organizations to advocate for just climate policies and has provided expert testimony at the Minnesota State Capitol on the public health impacts of climate change. Her work has been featured in MPR, Minnesota Daily, Common Dreams and the Associated Press. Follow her @LaaliMD on Twitter for information on how climate change impacts our health and the role health professionals can play in climate action.



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