Vape users risk developing serious illnesses such as pulmonary alveolar proteinosis, where fats and proteins clog the lungs, leading to breathing difficulties.

Mr D turned to vaping to quit his 15-year smoking addiction, but ended up getting hooked on both vaping and smoking instead. Worse was to come — just a month later, he started coughing green phlegm and had lower back pain; a couple of weeks after, he became breathless and was admitted to the intensive care unit (ICU) for weeks. ICU did not help and his oxygen saturation levels — the amount of oxygen-saturated haemoglobin — plunged from normal levels of at least 95 per cent, making him breathless. He had to be admitted to Singapore General Hospital (SGH) for a procedure known as lung lavage, where the lungs are literally washed.

Dr Melvin Tay (above), Senior Consultant, Department of Respiratory and Critical Care Medicine, SGH, suspected Mr D had developed pulmonary alveolar proteinosis (PAP), a rare and potentially life-threatening condition where the lungs are clogged with protein, fats and other substances in the air sacs. It was later confirmed through tests.

“We couldn’t be sure if there was a causal relationship between his symptoms and vaping, but there was a temporal relationship between the two,” said Dr Tay, noting that in 2019, there was an epidemic of sorts in the United States of America involving mostly young people developing lung problems that coincided with an increased use of e-cigarettes or vaping.

Indeed, in 2020, the US’s Center for Disease Control and Prevention (CDC) confirmed 2,807 cases of e-cigarette or vaping use-associated lung injury (EVALI) and 68 deaths attributed to EVALI. The CDC also identified vitamin E acetate as a chemical of concern among people with EVALI. Vitamin E acetate is a thickening agent often used in vaping products, and it was found in all lung fluid samples of EVALI patients examined by the CDC.

Known variously as vapes, vape pens, vapourisers, mods or electronic nicotine delivery systems, e-cigarettes heat nicotine, flavourings and other chemicals to create an aerosol that is inhaled. “We don’t know what those flavourings and chemicals are, or their effects. Some e-cigarettes may not even have nicotine,” said Dr Tay. E-cigarettes are banned in Singapore, but they are easily bought outside the country or online.

A 2018 survey of 600 youths by the Health Promotion Board (HPB) found that over 70 per cent of them were unaware that e-cigarettes contain nicotine and cancercausing chemicals, and that the vapour contains fine particles that can cause respiratory diseases.

Read more: Is vaping safer than cigarettes and less addictive? Find out here. 

Mr D underwent lung lavage twice, as he resumed smoking and vaping after the first procedure. “My whole body ached. It was like being hit by a bus,” said Mr D of the procedure. It took him months for his lungs to recover and for his oxygen saturation levels to return to normal.

In lung lavage, performed under general anaesthesia, 10 to 20 litres of warm saline is delivered via a double lumen endotracheal tube into a lung. The tube allows for one lung to be isolated for the procedure while keeping the other ventilated. Each procedure takes four to five hours.

A vest is wrapped around the patient’s chest, the body is then shaken, forcing the substances in the air sacs to be dislodged together with the saline. The process is repeated until the drained fluid becomes clear. The same procedure is then performed for the other lung at least a week later, said Dr Tay.

PAP is so rare that lung lavage is only done at SGH, where members of the team have performed the procedure just a few times in the past. Besides Dr Tay, lung anaesthetists and physiotherapists with expertise in the procedure make up the rest of the team.

For those who think e-cigarettes are a good alternative to smoking, there is no evidence that shows their safety and effectiveness in smoking cessation. Known safe and effective methods include smoking cessation counselling and, for those who need more help, nicotine replacement therapy.

For more on smoking, vaping and ways to quit both habits, tune in to the Perfectly Imperfect Health podcast series. Go to

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