This blog post was authored by Katie Keating, RN, MS, and reviewed by the Bronchiectasis and NTM Content Review and Evaluation Committee.

Sunshine, warmer weather, and longer outdoor days are a highlight of summer. There are so many great parts of summertime but for those dealing with lung conditions, the summertime can leave you more prone to heat-related issues. Heat-related illnesses happen when the body is unable to regulate its temperature when the temperature outside is high.

Mild forms of heat-related illness include edema (swelling), muscle cramps, and heat rash (miliaria rubra). Swelling can occur in the lower body, specifically the legs and feet. This is usually relieved by elevating the legs. A heat rash is caused when pores in the skin that are covered with clothing become trapped with sweat.¹

If mild heat-related illness progresses, it can lead to heat exhaustion.¹ Some signs of heat exhaustion occurring include hot skin, little to no sweating, increased heart rate, confusion, and poor coordination. Heat exhaustion can also cause headaches, dizziness, nausea, or vomiting. These conditions can lead to heat stroke if they aren't treated.¹

Heatstroke, also called sunstroke, is the most severe form of heat-related illness. Heatstroke occurs when your body cannot cool itself down. It is caused when your body temperature reaches 104 or higher as a result of ongoing exposure to heat or exertion in high temperatures.²

There are 2 types of heatstroke: exertional and non-exertional. Exertional heatstroke usually results from being too active in hot, humid conditions. This can happen in as little as 2 hours. Non-exertional heatstroke occurs after exposure to hot, humid weather for long periods. Non-exertional heat stroke can occur due to age or chronic health conditions. It tends to develop over several days.²

Heatstroke Symptoms may include confusion, seizures, agitation, slurred speech, trouble walking, or loss of consciousness. High heart rates, headache, nausea, and vomiting are also symptoms.²

Risk factors that may increase your risk of heat-related illness include:

• Age
• Sudden increase in temperature, such as an intense heat wave
• Lack of air conditioning
• Drugs that affect your body’s ability to regulate temperatures (e.g., diuretics, sedatives, anti-depressants, heart and blood pressure medications) Talk to your pharmacist or health care provider if you are not sure if your medications impact temperature regulation.
• Certain diseases that affect your ability to sweat (e.g., people who have borderline sweat test results but do not have cystic fibrosis and those that have cystic fibrosis)
• Being overweight, sedentary, and having a history of previous heatstroke increases your risks^2,3

How you can prevent heat-related illness.

• Wear loose-fitting, lightweight, and light color clothing. Wearing excess clothing or tightly fitting clothing won't allow your body to cool adequately.
• Wear a hat and sunglasses and use sunscreen with an SPF of at least 15. Reapply every two hours.
• Drink adequate fluids, such as water or sports drinks, lightly salted water, or broth.
• Be cautious about drinking alcohol.
• Never leave anyone in a parked car. The temperature in your car can rise 20 degrees F (more than 11 C) in 10 minutes when parked in the sun.
• Exercise early in the day before it gets too hot.
• If you must be in hot temperature conditions, slowly let your body get used to the warmer temperatures over time. Limit activity for a few days to allow yourself to adapt to the change.
• Air conditioning is the most effective way to cool down and lower humidity.³

MANAGEMENT AND TREATMENT

Heatstroke requires immediate medical treatment. Call 911 or your local emergency services number if you or anyone is showing signs of heatstroke. While waiting for emergency staff to provide medical attention, take immediate action to cool the overheated person as much as possible by:

• Moving to a cooler area
• Removing excess clothing
• Misting with cold water
• Fanning to blow air on wet skin
• Applying ice packs
• Ice bath, cool shower
• Drinking slightly salted fluids, such as sports drinks (Do not offer drinks containing alcohol or caffeine.)
• Not giving any medications, including aspirin and acetaminophen.

If those with bronchiectasis and NTM lung disease do not protect themselves from having heat-related illnesses, serious complications and even death could occur.³

Author’s personal comments

Health conditions, medications, and lack of air conditioning may contribute to the risks of heatstroke. I experienced heat exhaustion twice when I was on the “Big 3“ medications. The “Big 3” refers to the combination of Zithromax, Ethambutol, and Rifampin used to treat MAC lung infections. I remember feeling so off when I got out of my car on a very hot day. I had to stand for a while because I could not walk. It really took me some time to regroup. I also experienced heat exhaustion while sitting at a pool for an extended period of time during the following summer on the “Big 3”. I was much younger then and denied what I was experiencing was heat exhaustion, even as a registered nurse. I was surely wrong in my assumption. I often used the coping mechanism of denial when I didn’t want to accept my new reality. Some people can tolerate the sun while taking the “Big 3” and other medications without any issues, others cannot.

After you’ve had heatstroke once, you’re more likely to get a heat-related illness again. Take preventive measures any time you plan to be in very hot conditions. Be mindful that heat-related issues are a possibility and take immediate action to resolve issues once you start noticing the symptoms. Pick and choose the activities, timeframes, and conditions that are most suitable for you. Stay safe and have an enjoyable summer!

References:

1. Heat-Related Illnesses, American Family Physician, Date published, April 15, 2019, Date accessed, May 23rd, 2023. https://www.aafp.org/pubs/afp/issues/2019/0415/p482.html
2. Heatstroke: What Is It, Symptoms, Causes, Treatment & Recovery, Cleveland Clinic, https://my.clevelandclinic.org/health/diseases/21812-heatstroke
3. Heatstroke, Mayo Clinic, Date published, June 25, 2022, Date accessed, May 21^st, 2023 https://www.mayoclinic.org/diseases-conditions/heat-stroke/symptoms-causes/syc-20353581