Can Unmanned Aerial Systems (Drones) Be Used for the Routine Transport of Chemistry, Hematology, and Coagulation Laboratory Specimens?

Unmanned Aerial Systems (UAS), colloquially known as drones, are aircraft without an on-board human pilot. On December 1st 2013 Amazon. com introduced the world to the idea of civilian drones when its CEO unveiled Prime Air, a delivery drone, on live TV. However UAS are not new. They have been in use since the early 1900's[1]but were primarily developed and flown by military organizations due to their enormous cost. Recent advances in technology have provided high quality sensors at low price-points, greatly expanding the availability and potential utility of UAS. One of these potential new uses is the routine transport of small goods such as diagnostic clinical laboratory specimens.

Transport of biological specimens, whether by planes, trains, or cars, is ubiquitous in both high-and low-resourced environments[2–4]. The majority of specimens are obtained in physician offices or clinics that tend to have small laboratories with limited testing menus[5, 6]. Thus samples must be transported to larger, more complex laboratories to provide the testing required for clinical care. To illustrate, there are approximately 244,000 laboratories in the United States[7]. In 2006, physician office and other small non-hospital clinical laboratories accounted for~75% of the total number of laboratories[6, 8], but they only accounted for 13% of the test volume. In addition 63% of their testing was in a point-of-care format which proffers a limited range of tests relative to core laboratory testing[6, 8]. A 2011 survey of clinical laboratories in Kampala, Uganda showed the same pattern.

In addition to being a potentially new mode of transporting biological samples, UAS have unique advantages such as no traffic delays, low overhead costs, and the ability to go where there is no passable road. The impact of poor or difficult road access on healthcare is well documented in both high-[10]and low-resourced[11, 12]countries. UAS are a potential way around this barrier, but are only useful if they do not adversely affect the test results of transported samples[2, 13–16].

Our first challenge in addressing the impact of UAS transport on laboratory results was the high and expanding number of tests used in clinical care[17]. Fortunately, less than 0.5% (40/2000) of these tests account for 80% of the test volume. Thus we began by focusing, in these first experiments, on the impact of UAS transport on the 33 most common tests performed in hospital laboratories[17, 18]. A second challenge was determining what quality criteria to use for evaluating any differences we might see. There is no single worldwide consensus on acceptable performance for laboratory tests. The most widely used performance criteria are intended for interpretation of External Quality Assessment reports. They are largely measures of accuracy, and vary by jurisdiction[19–22]. To account for these limitations, we evaluated our results in three ways. 1) We used four performance acceptability criteria including two from groups outside the United States[19–22]; 2) We examined changes in reference range-based clinical classification; and 3) We examined differences between laboratory-derived (analytic) CV's and that from our paired samples.

To the best of our knowledge there has been no published research of the impact of UAS transportation on the stability of biological specimens or on the laboratory test results obtained from those specimens. Obtaining this data, which would be needed to determine the feasibility of UAS transportation of biological samples, is the objective of this study.

Our findings demonstrate that, for the 33 test-types in this study, laboratory results from UAS-transported samples agree with those transported terrestrially: there were no systematic differences in results from flown versus terrestrial specimens. However, there was slightly worse precision in the flown samples. Full adoption of UAS transport of diagnostic specimens will require similar studies for other types of laboratory tests, specimens, and environmental conditions.