We intend to build and test a unique precision patient bed scale system (PBSS) to improve the accuracy, precision, resolution and usefulness of weighing patients in a bed or a chair. The PBSS uses a unique dynamic technique to measure patient-bed weight. The dynamic measurement technique provides a means to include self-diagnostics for the sensors and electronics. This system has the potential of improving the accuracy of measuring patient weight by as much as a factor of 50 when compared to commercial patient-bed weighting systems. The PBSS is intended for patients who are temporarily or permanently incapacitated and cannot be transferred from a bed to a scale easily, comfortably, or conveniently. Its precision sensitivity and dynamic range will permit the early detection and treatment of fluid imbalances accuracy and the longer-term follow-up of nutritional problems. These applications are most relevant to the management of patients in intensive care units with their heavy' extensively instrumented beds bed ridden on pediatric or adult hospital rehabilitation or extended care nursing floors, confined to special beds such as Stryker frames, undergoing inpatient and outpatient rental dialysis, or in premature nurseries. Additionally, the PBSS can be used to continuously monitor patient activity while in bed. A team consisting of a technical manager, a physician, and several design and test engineers will combine their expertise to design, construct and test a low-cost precision piezoelectric load cell, formulate a suitable design for the pneumatic lift system, and fabricate and test a prototype unit. In Phase I research the prototype system will be tested using a commercial hospital bed. The PBSS represents a significant advancement in high capacity, high resolution, rugged patient-bed weighting systems. This system can be retrofitted to any commercial hospital bed, cribs incubator, or reclining chair without interfering with patient care or the operation of the bed. Awardee's statement of the potential commercial applications of their search: The proposed PBSS can be retrofitted to any commercial hospital bed, crib, incubator, or reclining chair. About 1.26 million hospital beds [Source: American Hospital Association, Hospital Statistics, 1988] are in use in the United States. A commercial PBSS would cost about $2000, equivalent to state-of-the-art electronic platform scales. Instrumenting one percent of the existing hospital beds with the proposed scale system represents a $25,000,000 market. We believe the world market is an additional $50,000,000 to $75,000,000. Instrumenting reclining chairs used in dialysis and incubators in premature nurseries would probably develop a market equal to that for hospital beds. National Institute for Nursing Research (NCNR)
