Effect of parachute delivery on red blood cell (RBC) and plasma quality measures of blood for transfusion.

BACKGROUND: Parachute airdrop offers a rapid transfusion supply option for humanitarian aid and military support. However, its impact on longer-term RBC survival is undocumented. This study aimed to determine post-drop quality of RBCs in concentrates (RCC), and both RBCs and plasma in whole blood (WB) during subsequent storage. STUDY DESIGN AND METHODS: Twenty-two units of leucodepleted RCC in saline, adenine, glucose, mannitol (SAGM) and 22 units of nonclinical issue WB were randomly allocated for air transportation, parachute drop, and subsequent storage (parachute), or simply storage under identical conventional conditions (4 ± 2°C) (control). All blood products were 6-8 days post-donation. Parachute units were packed into Credo Cubes, (Series 4, 16 L) inside a PeliCase (Peli 0350) and rigged as parachute delivery packs. Packs underwent a 4-h tactical flight (C130 aircraft), then parachuted from 250 to 400 ft before ground recovery. The units were sampled aseptically before and after airdrop at weekly intervals. A range of assays quantified the RBC storage lesion and coagulation parameters. RESULTS: Blood units were maintained at 2-6°C and recovered intact after recorded ground impacts of 341-1038 m s-2 . All units showed a classical RBC storage lesion and increased RBC microparticles during 42 days of storage. Fibrinogen and clotting factors decreased in WB during storage. Nevertheless, no significant difference was observed between Control and Parachute groups. Air transportation and parachute delivery onto land did not adversely affect, or shorten, the shelf life of fresh RBCs or WB. DISCUSSION: Appropriately packaged aerial delivery by parachute can be successfully used for blood supply.

Protection of the lung from blast overpressure by stress wave decouplers, buffer plates or sandwich panels.

INTRODUCTION: This paper outlines aspects of UK Ministry of Defence's research and development of blast overpressure protection technologies appropriate for use in body armour, with the aim of both propagating new knowledge and updating existing information. METHODS: Two simple models are introduced not only to focus the description of the mechanism by which the lungs can be protected, but also to provide a bridge between fields of research that may hold the key to further advances in protection technology and related body armour. RESULTS: Protection can be provided to the lungs by decoupling the stress wave transmission into the thorax by managing the blast energy imparted through the protection system. CONCLUSIONS: It is proposed that the utility of the existing 'simple decoupler' blast overpressure protection is reviewed in light of recent developments in the treatment of those sustaining both overpressure and fragment injuries. It is anticipated that further advances in protection technology may be generated by those working in other fields on the analogous technologies of 'buffer plates' and 'sandwich panels'.