E-cigarette, or Vaping Product, Use Associated Lung Injury (EVALI)
Übersicht
In the summer of 2019, the Centers for Disease Control and Prevention (CDC) began to investigate a steep rise in hospitalizations linked to the use of vaping products. The patients complained of a host of respiratory symptoms including shortness of breath, cough, and chest pain. They all shared one thing in common: They had used vaping products within the previous three months.
The condition came to be called “e-cigarette, or vaping, product use associated lung injury,” or EVALI. By February 2020, the CDC had recorded over 2800 hospitalizations due to EVALI along with 68 deaths caused by the condition.
Fortunately, there has been a substantial drop in cases since they peaked in August and September of 2020. What’s more, researchers have also identified vitamin E acetate, a chemical added to some THC-containing vaping products, as the main—but possibly not the only—cause of the illness. The outbreak of EVALI cases emerged against a backdrop of an ongoing vaping epidemic among youth. According to the CDC, 15% of EVALI patients were less than 18 years old.
At Yale Medicine, most pediatricians have started asking middle- and high school-age patients about their exposure to vaping, in large part to identify patients who might be at higher risk for developing related problems.
“I screen all of my patients, any child over age 12, since [vaping] can exacerbate underlying conditions like asthma,” says Yale Medicine pediatric pulmonologist Pnina Weiss, MD.
What is EVALI?
EVALI is a serious medical condition in which a person’s lungs become damaged from substances contained in e-cigarettes and vaping products.
Vaping involves using a device known as an e-cigarette—also called a vape pen, mod, or tank—to heat up a small amount of liquid, turning it into a vapor that can be inhaled. Most vape liquids contain substances such as propylene glycol and glycerol as base ingredients that create the vapor. But they may also contain other compounds including artificial flavors, nicotine, THC, and cannabinoid (CBD) oil.
What are the symptoms of EVALI?
EVALI may cause the following symptoms:
- Shortness of breath
- Cough
- Chest pain
- Fever and chills
- Diarrhea, nausea, vomiting, and abdominal pain
- Rapid heartbeat
- Rapid and shallow breathing
What are the causes of EVALI?
Researchers have linked vitamin E acetate, a synthetic form of vitamin E found in some THC-containing vaping products, to EVALI. When inhaled, the chemical can damage the lungs. One study detected vitamin E acetate in the lung fluid of 48 out of 51 EVALI patients sampled across 16 states. By contrast, lung fluid samples taken from healthy people did not contain the vitamin.
Because of this and other studies, vitamin E acetate is considered the main cause of EVALI. Other chemicals found in nicotine- and THC-containing vaping products may also play a role in the condition.
What are the risk factors of EVALI?
The primary risk factor for EVALI is current or previous use of a vaping device.
In particular, use of vaping devices that contain THC have been associated with the condition. According to the CDC, over 80% of people hospitalized due to EVALI reported use of vaping products that contained THC, though many also said they used nicotine-containing products. The CDC further notes that nearly 80% of EVALI patients who used THC-containing e-cigarettes obtained their vaping products from “informal sources” including family, friends, dealers, or online sources, rather than commercial outlets.
How is EVALI diagnosed?
Diagnosing EVALI can be challenging because the symptoms of this lung condition are similar to those of other respiratory illnesses, like pneumonia and even the seasonal flu virus.
There is no single test for EVALI; it’s what is known as a “diagnosis of exclusion,” which means that a doctor will conduct tests to rule out other potential diseases and conditions.
Your doctor will begin his or her diagnosis by asking you about your use of e-cigarettes within the past three months and whether you vaped a product containing nicotine, THC, or both. During the physical exam, your doctor will use a stethoscope to listen to your lungs, check your heartrate, and measure your blood oxygen saturation using a pulse oximeter. A chest X-ray or computed tomography (CT) scan is usually necessary for diagnosis and will show hazy looking spots (called opacities) in the lungs. This contrasts with a clear back space in healthy lungs. Your doctor may also order bloodwork to rule out other possible causes of your illness.
What is the treatment for EVALI?
Many people diagnosed with EVALI need to be treated in a hospital where medications can be closely monitored, and respiratory support is readily available.
Treatments may include:
- Corticosteroids. A type of medication that reduces inflammation in the lungs and throughout the body.
- Supportive care. Patients may receive supplemental oxygen through a nasal cannula. In more severe cases, they may be put on a mechanical ventilator or an extracorporeal membrane oxygenation machine.
- Antibiotics. These drugs may be given to the patient while diagnostic test results are being finalized as it’s difficult to distinguish EVALI from bacterial infections.
- Antivirals. Because EVALI causes similar symptoms to some viral infections, antivirals may be used, especially during influenza season.
What is the outlook for someone with EVALI?
Because the illness is so new, there is no way to predict how patients will fare after being released from the hospital following treatment. Dr. Weiss says that some have become ill again after steroid treatment is stopped, so follow-up care is vital.
“We recommend that patients see a pulmonologist within one to two weeks after being discharged to undergo testing of lung function and pulse oximetry [level of oxygen in the blood],” she says.
Because of the lack of long-term data and the fact that patients have died from EVALI, the prognosis for those affected remains uncertain. Researchers are working hard to learn as much as possible about the illness, its causes, and the odds for making a full recovery.
How is Yale Medicine unique in its approach to EVALI?
“Yale physicians have been at the forefront in identifying EVALI cases,” Dr. Weiss says. She explains that even before CDC guidelines on treating the illness were released, Yale doctors were successfully treating patients with a combination of antibiotics and steroids. Doctors at Yale Medicine also collaborate with researchers in the fields of tobacco and addiction medicine to provide care for patients with EVALI.