Publications

Hemorrhage is a leading cause of trauma death, particularly in prehospital environments when evacuation is delayed. Obtaining central vascular access to a deep artery or vein is important for administration of emergency drugs and analgesics, and rapid replacement of blood volume, as well as invasive sensing and emerging life-saving interventions. However, central access is normally performed by highly experienced critical care physicians in a hospital setting. We developed a handheld AI-enabled interventional device, AI-GUIDE (Artificial Intelligence Guided Ultrasound Interventional Device), capable of directing users with no ultrasound or interventional expertise to catheterize a deep blood vessel, with an initial focus on the femoral vein. AI-GUIDE integrates with widely available commercial portable ultrasound systems and guides a user in ultrasound probe localization, venous puncture-point localization, and needle insertion. The system performs vascular puncture robotically and incorporates a preloaded guidewire to facilitate the Seldinger technique of catheter insertion. Results from tissue-mimicking phantom and porcine studies under normotensive and hypotensive conditions provide evidence of the technique's robustness, with key performance metrics in a live porcine model including: a mean time to acquire femoral vein insertion point of 53 plus or minus 36 s (5 users with varying experience, in 20 trials), a total time to insert catheter of 80 plus or minus 30 s (1 user, in 6 trials), and a mean number of 1.1 (normotensive, 39 trials) and 1.3 (hypotensive, 55 trials) needle insertion attempts (1 user). These performance metrics in a porcine model are consistent with those for experienced medical providers performing central vascular access on humans in a hospital.

The Integrated Terminal Weather System (ITWS) is a high-resolution weather information system designed to operate within the TRACONs surrounding the country's major airports. Targeted for those airports most often adversely affected by convective weather, the system was developed for the Federal Aviation Administration (FAA) by the Massachusetts Institute of Technology's Lincoln Laboratory (MIT/LL) Weather Sensing Group. The ITWS acquires data from Next Generation Radars (NEXRAD), Terminal Doppler Weather Radars (TDWR), Airport Surveillance Radars (ASR-9), Low Level Windshear Alert Systems (LLWAS), the National Lightning Detection Network (NLDN), Automated Weather Observing Stations (AWOS/ASOS), and aircraft in flight. The system integrates the data to provide consistent weather information in a form that is usable without further meteorological interpretation. This information includes six-level precipitation at a number of ranges, windshear and microburst detection and prediction, storm motion and extrapolated position, wind fields, gust fronts, lightning, and storm cell information (hail, mesocyclone notification, and echo tops). A set of direct users of ITWS (FAA users at TRACONs, Air Traffic Control Towers, and en-route centers) will receive ITWS weather products through FAA-provided Situation Displays (SDs) that are tied directly to the ITWS processor. In addition, the FAA has sponsored development of an ITWS External Users Data Distribution System to provide real-time ITWS products to those users who do not have access to a dedicated SD. The data distribution system is being developed in conjunction with the upcoming deployment of the ITWS (2002-2004) as an operational FAA system serving 47 major airports. The need for a remotely accessible display is strongly supported by draft recommendations recently released by the National Transportation Safety Board (NTSB) that call for U.S. air carriers and all air traffic control facilities to have access to data from FAA terminal weather information systems. In addition, the Collaborative Decision Making program (CDM) has highlighted the need to make the information widely available to airlines. MIT/LL has operated demonstration ITWS systems since 1994, and a demonstration website since 1997. Most major airlines have successfully accessed the ITWS demonstration products in real time via Web browsers and have used this information to improve safety and reduce delays (Maloney, 2000). Benefits specific to airline dispatch include support for decisions made during diversion situations and improvements in hub operations . By sharing a common view of the same operational environment, controllers, dispatchers and other aviation decision makers and stakeholders have been better able to understand and coordinate the decisions that affect air traffic in the terminal area and surrounding en route airspace (Evans 2000). This paper describes the goals of the ITWS External Users Data Distribution System development project, including a discussion of the system architecture, data distribution and access methods, and the web-based interface.