Over 100,000 people are currently waiting for an organ transplant in the US alone, so when the rare opportunity arises to receive a donor organ, time really is of the essence. Fortunately, the efficiency of organ transport networks looks set to increase dramatically, after a woman at the University of Maryland Medical Center became the first person to receive a donor kidney that had been delivered by drone.

One of the major frustrations for those awaiting organ transplants is that suitable organs don’t come along very often. When someone who is on the organ donor list dies, their heart, lungs, kidneys, and certain other body parts can sometimes be rushed to a patient who needs a transplant, provided they are a match and can be reached quickly enough for the organ to remain viable.

Yet hearts and lungs can only survive outside the body for four to six hours, and often have to be transported by road or on chartered or commercial flights, which means delays are sometimes unavoidable. Furthermore, patients who are not near an airport may have no chance of ever receiving an organ in time.

To combat this, researchers developed a drone that is specifically designed to deliver human organs. The aircraft features eight rotors, giving it excellent stability, and is equipped with a system called the Human Organ Monitoring and Quality Assurance Apparatus for Long-Distance Travel. This measures and maintains temperature, barometric pressure, altitude, vibration, and location, ensuring the organ remains in perfect condition, while transmitting all the relevant information to the waiting surgeon’s smartphone.

The 44-year-old kidney recipient, who suffered from renal failure and had spent the past eight years on dialysis, underwent surgery on April 19th and was discharged from hospital three days later.

“This whole thing is amazing. Years ago, this was not something that you would think about,” she said after receiving a kidney that had been flown from another hospital roughly 4.8 kilometers (3 miles) away.

Unlike hearts and lungs, kidneys can survive outside the body for up to 48 hours, meaning they can be transported longer distances. However, finding a suitable kidney is tricky, as both the donor and recipient must be a match for blood type, body size, and immune system proteins called HLA antigens.

With all of this to think about, the last thing transplant surgeons want to have to deal with is travel delays, which is why the use of drones to deliver organs is such an important innovation.