Accession Number : ADA260777


Title :   In-line Microwave Warmer for Blood and Intravenous Fluids. Phase 2.


Descriptive Note : Final rept. 1 Dec 88-14 Jan 91,


Corporate Author : MICROWAVE MEDICAL SYSTEMS INC LITTLETON MA


Personal Author(s) : Grabowy, Richard S ; Carr, Kenneth L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260777.pdf


Report Date : 15 Feb 1988


Pagination or Media Count : 59


Abstract : To address the problem of hypothermia and its associated coagulopathy and cardiac dysfunction occuring with trauma, a technique has been conceived that provides in-line heating of blood and intravenous(IV) A fluids. The design is based on a microwave generator and chamber capable of uniform heating of fluids during the infusion process. An in-line unit overcomes the delay inherent with remote warming and the cooling occurring in a cold environment during transport of fluid or blood heated at a remote location. During the Phase I study a heating chamber with a wound bobbin of IV tubing has been developed that predictably and uniformly distributes a microwave energy field along the entire fluid path within the chamber. To determine the efficacy of the rapid, in-line warming of blood and IV fluids within this uniform microwave energy field, in- vitro tests(primarily with blood) have been conducted. Results confirm the rapidity and uniformity of the predicted heat transfer mechanism; laboratory analysis of the in-vitro blood samples warmed by the system show no significant changes in constituency from the control samples. To address the need for A feedback control mechanism to vary the delivered level of microwave energy as a function of flow rate and input temperatures, radiometric transducers have been designed, fabricated and evaluated for non-invasive temperature measurement of the flowing fluid. Results show that the response times of a microwave radiometry system using these transducers at the inlet and outlet ports of the heating chamber and within the heating chamber itself are sufficient for reliable feedback control.


Descriptors :   *BLOOD , *MICROWAVE OVENS , TEST AND EVALUATION , HEAT TRANSFER , INPUT , CONTROL , SOURCES , MEASUREMENT , TEMPERATURE , ENVIRONMENTS , WATER , BIOCHEMISTRY , VOLUNTEERS , ENERGY , PATHS , COOLING , IN VITRO ANALYSIS , PHASE , FLOW RATE , HEMATOLOGY , CARTRIDGES , BABOONS , DISPOSABLE EQUIPMENT , UNIFORMS , DYSFUNCTION , BATHS , TRAUMA , VEINS , INFUSIONS , RESPONSE , FEEDBACK , HEATING , SAMPLING , TRANSPORT , DELAY , FLUIDS , TRANSDUCERS , LABORATORIES , GENERATORS , IN VIVO ANALYSIS , INLETS , RADIOMETRY , HYPOTHERMIA , CHAMBERS


Subject Categories : Medical Facilities, Equipment and Supplies
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE