Safest light in a combat area while performing intravenous access in the dark

Cannulation for the administration of intravenous fluids is integral to the prehospital management of injured military patients. However, this may be technically challenging to undertake during night-time conditions where the use of light to aid cannulation may give the tactical situation away to opponents. The aim of this study was to investigate the success and tactical safety of venepuncture under battlefield conditions with different colour light sources.

The procedure was carried out with naked eye in a bright room in the absence of a separate light source, with a naked eye in a dark room under red, white, blue and green light sources and under an infrared light source while wearing night vision goggles (NVGs). The success, safety, degree of difficulty and completion time for each procedure were then explored.

All interventions made in daylight and in a dark room were found to be 100% successful. Interventions performed under infrared light while wearing NVGs took longer than under other light sources or in daylight. Interventions performed under blue light were tactically safer when compared with interventions performed under different light sources.

Blue light offered the best tactical safety during intravenous cannulation under night-time conditions and is recommended for future use in tactical casualty care. The use of NVGs using infrared light cannot be recommended if there is the possibility of opponents having access to the technology.