More airplane passengers are suffering from in-flight health problems such as breathing trouble or blood clots as travel time increases, according to a review in the U.K. journal Lancet, dpa reported.
Reduced cabin pressure can lead to lower oxygen saturation in the blood, which may worsen pre-existing heart, lung or blood ailments, two U.S. emergency medicine specialists wrote in the review. Jet lag, cosmic radiation and poor air quality resulting from vaporized jet fuel entering the cabin may also affect passengers' health, they said.
Almost 2 billion people travel on commercial airlines every year, according to the authors, Mark Gendreau from the Lahey Clinic Medical Center in Burlington, Massachusetts, and Danielle Silverman from Georgetown University Hospital and Washington Hospital Center. The age of travelers is increasing, and aircraft such as the Airbus A380 and Boeing 777 LR are able to fly for as long as 20 hours, raising the risk of medical events, they said.
"In-flight medical events are increasingly frequent because a growing number of individuals with pre-existing medical conditions travel by air," Gendreau and Silverman wrote.
Cabin pressure at cruising altitude causes gases in the body to expand by 30 percent, causing cramps and ear trauma, they said. The pressure can be a major problem for people who have had recent heart or lung surgery, and those patients should wait at least two weeks after their operations to fly, the two physicians said.
Respiratory Distress
The expansion of gases may lead to respiratory distress during the flight in people suffering from chronic obstructive pulmonary disease, also known as COPD or smoker's cough, they said, citing an observational study.
When passengers are immobilized on airplanes for more than eights hours at a time, the risk of blood clots increases as much as four-fold, with no difference whether they travel business or economy class, the two doctors wrote, citing earlier research. Recommendations for avoiding clots include rehydration, reducing alcohol and caffeine consumption, exercise, compression stockings and blood-thinning pills.
Confined spaces on aircraft also facilitate the spread of infectious disease such as influenza, measles, severe acute respiratory syndrome, tuberculosis and food poisoning. Still, the main complaints are minor heart, brain or respiratory trouble in passengers older than 70, Silverman and Gendreau wrote.
"Individuals need to be aware of the possible medical complications of air travel, and physicians should identify people at potential risk and advise them of any necessary treatments to travel safely," they said. "In the modern travel era, clear understanding of the medical consequences of commercial flights has become increasingly important."