Drone transport does not affect blood samples

Bringing health care to millions of people in rural and impoverished parts of the world is often hampered by impassable roads and long distances between clinics and labs. Now, a new study suggests using medical drones to carry blood samples could help by giving health workers quick access to lab tests needed for diagnoses and treatments.

Pathologist Timothy Amukele, left, and engineer Robert Chalmers fly the drone that was tested to see if it could carry blood samples to a remote lab without damaging them.
Image credit: Johns Hopkins Medicine

The study - a collaboration between a pathologist and engineers - was carried out at Johns Hopkins University School of Medicine in Baltimore, MD, and is published in the journal PLOS ONE.

The purpose was to test the feasibility of using a drone courier system to transport blood to diagnostic labs and to find out whether the blood samples arrive in good condition for diagnostic testing.

The study is thought to be the first to rigorously test the effect of drone travel on biological samples.

The team found that common and routine blood test results are not affected by up to 40 minutes of travel on the hobby-sized drones.

In fact, biological samples can be very sensitive and fragile. That sensitivity makes even the pneumatic-tube systems used by many hospitals, for example, unsuitable for transporting blood for certain purposes.

Flown and non-flown blood samples underwent 33 different lab tests

The features of drone use that the team was particularly concerned about were the sudden acceleration when the device launches and the jostling when it lands. Such movements could destroy blood cells or cause the blood to coagulate.

The researchers thought all kinds of blood tests might be affected, but their study shows they weren't, so that was cool.

For the study, the team collected six blood samples from 56 health volunteers at Johns Hopkins Hospital and drove them to a location an hour's drive away on days when the temperature was 70 °F (21 °C) or higher.

Half the samples were then packaged and placed in a hand-launched, fixed-wing drone and flown around for periods of 6-38 minutes.

In line with Federal Aviation Administration (FAA) rules, the flights took place in an unpopulated area, the drone stayed below 100 m, and it remained in the certified pilot's sight all the time.

All the samples (flown and non-flown) were then driven to a lab at the hospital where they underwent the 33 most common lab tests. These tests account for around 80% of all tests done on blood samples and include, for example, tests for sodium and glucose and red blood cell count.

Prof. Amukele says when they compared the results between the flown and non-flown samples, "the flight really had no impact."

Next step is to pilot the drone in Africa

However, the team did note that the flown versus non-flown samples showed different results on the test for total carbon dioxide - the so-called the bicarbonate test.

The researchers say they are not sure why, but one reason could be the samples sat around for up to 8 hours before they were tested.

They could not determine whether the out-of-range results were due to the flight or the time lag and there is no way to find out, except perhaps by flying blood samples around the hospital straight after taking them, "but neither the FAA nor Johns Hopkins would like drones flying around the hospital."

The next step is likely to be a pilot study in Africa, where clinics can be 60 or more miles away from testing labs. The researchers explain some of the potential benefits:

"A drone could go 100 km in 40 minutes. They're less expensive than motorcycles, are not subject to traffic delays, and the technology already exists for the drone to be programmed to 'home' to certain GPS coordinates, like a carrier pigeon."

References:

Johns Hopkins University - July 2015