Development and Characterization of a Nonelectronic Versatile Oxygenating Perfusion System for Tissue Preservation.

Oxygenated machine perfusion of human organs has been shown to improve both preservation quality and time duration when compared to the current gold standard: static cold storage. However, existing machine perfusion devices designed for preservation and transportation of transplantable organs are too complicated and organ-specific to merit use as a solution for all organs. This work presents a novel, portable, and nonelectronic device potentially capable of delivering oxygenated machine perfusion to a variety of organs. An innovative pneumatic circuit system regulates a compressed oxygen source that cyclically inflates and deflates silicone tubes, which function as both the oxygenator and perfusion pump. Different combinations of silicone tubes in single or parallel configurations, with lengths ranging from 1.5 to 15.2 m, were evaluated at varying oxygen pressures from 27.6 to 110.3 kPa. The silicone tubes in parallel configurations produced higher peak perfusion pressures (70% increase), mean flow rates (102% increase), and oxygenation rates (268% increase) than the single silicone tubes that had equivalent total lengths. While pumping against a vascular resistance element that mimicked a kidney, the device achieved perfusion pressures (8.4-131.6 mmHg), flow rates (2.0-40.2 mL min-1), and oxygenation rates (up to 388 µmol min-1) that are consistent with values used in previous kidney preservation studies. The nonelectronic device achieved those perfusion parameters using 4.4 L min-1 of oxygen to operate. These results demonstrate that oxygenated machine perfusion can be successfully achieved without any electronic components.

Review of Commercially Available Supraglottic Airway Devices for Prehospital Combat Casualty Care.

BACKGROUND: Airway obstruction is the second leading cause of potentially survivable death on the battlefield. The Committee on Tactical Combat Casualty Care lists airway optimization among the top 5 battlefield research and development priorities; however, studies show that combat medics lack access to the recommended supraglottic airway (SGA) devices. SGA devices are an alternative airway management technique to endotracheal tube intubation. Reports have shown SGA devices are easier to use and take fewer attempts to provide patent airflow to the patient when compared to endotracheal tube intubation. Military settings require a higher degree of skill to perform airway management on patients due to the environment, limited availability of equipment, and potential chaos of the battlefield. Finding the optimal SGA device for the military setting is an unmet need. The International Organization for Standardization describes basic functional requirements for SGA devices, as well as patient configurations and size limitations. Beyond that, no SGA device manufacturer states that their devices are intended for military settings. MATERIALS AND METHODS: We conducted a market review of 25 SGA devices that may meet inclusion into the medics' aid bag. The company's official "Instructions for Use" document, Google Scholar, and FDA reports were reviewed to obtain information for each SGA device. RESULTS: Twenty-five commercially available SGA devices are explored from manufacturer online sources. A commercially available device list is shown later in this paper, which provides the device's features, indications, and contraindications based on the manufacturer's product information documentation. CONCLUSIONS: There are a variety of devices that require further testing to determine whether they should be included in sets, kits, and outfits.