By Girish Linganna

May 20: As the science of organ transplants gets better, the biggest problems are things like getting a flight and getting through traffic quickly enough to give an organ before it gets worse.

Researchers recently wrote about a big test of the drone in Science Robotics. After a lot of practise, their drone took a human donor lung from the roof of Toronto Western Hospital to the roof of Toronto General Hospital in five minutes for a successful transfer. By car, the trip can take 25 minutes.

Drone delivery "may have a unique opportunity for organs like hearts and lungs that can tolerate less time on ice," adds Joseph Scalea, a transplant surgeon now at Medical University of South Carolina who was not involved in the study. His group at the University of Maryland was the first to successfully transport a kidney by drone in 2019; the organ can be kept alive for up to 24 hours in ice. The heart and lungs can withstand half that time without any ill effects.

For the current investigation, researchers from Toronto General Hospital and Unither Bioelectronics replaced a commercial drone's landing gear with a lightweight carbon-fiber container for the huge and fragile organ.

In order to prevent radio waves from interfering with the drone's GPS, the team upgraded the drone's connectivity and included a parachute that would deploy automatically in the event of a crash.

Since the successful test flight, the researchers have been collaborating with aviation authorities to develop a drone route through commercial airspace—but there are regulatory obstacles to overcome. In heavily populated locations, for example, civilians are often not permitted to fly drones outside their visible line of sight.

Shaf Keshavjee, who runs the lung donation programme at Toronto General, thinks that drones could one day carry lungs long distances to get them ready for transplant. For now, though, he is focused on the trip from the airport to the hospital, which takes 40 minutes in traffic but only eight minutes by drone. He thinks that the first flights of this kind could happen as soon as this summer. His work is called "The Last-Mile Model."

The author is an aerospace and defence analyst.