Carbon-Dioxide and Oxygen Respiratory Ventilator Energy Tracker (CORVET)
Accurate measurement of oxygen consumption (VO₂) and carbon dioxide production (VCO₂) is fundamental for evaluating energy expenditure, macronutrient utilization, and overall metabolic health. These data are particularly crucial in demanding clinical environments, such as critical care units and during anesthesia, in which precise metabolic assessment can significantly impact patient management and outcomes. Continuous and reliable monitoring is essential for tailoring nutritional support and therapeutic interventions. Existing indirect calorimetry systems face several significant limitations. Many commercial devices are cumbersome and expensive, providing only intermittent data inadequate for comprehensive 24-hour metabolic tracking. Breath-by-breath systems, while offering high temporal resolution, demand costly, high-speed sensors and complex synchronization, rendering them impractical for mechanically ventilated patients. Furthermore, prior miniature mixing chamber designs require frequent manual calibration, are restricted to short-term measurements, suffer from issues like filter clogging, and often necessitate disrupting patient ventilation for sampling.
Technology Description
The Carbon-Dioxide and Oxygen Respiratory Ventilator Energy Tracker (CORVET) is a respiratory monitoring system designed for continuous, long-term measurement of oxygen consumption (VO₂) and carbon dioxide production (VCO₂), particularly in mechanically ventilated patients. It utilizes miniature mixing chambers that physically average gas samples over multiple respiratory cycles, enabling the use of slower, more cost-effective gas sensors. The system employs passive flow dividers for flow-rate proportional sampling without disrupting ventilation and autonomously detects and compensates for sensor calibration drift. It can be configured with one or two chambers, with the dual-chamber setup allowing for periodic "chamber swapping" to enhance accuracy, perform calibration checks, and provide redundancy.
This technology differentiates itself by overcoming significant limitations of current indirect calorimetry devices. Unlike existing bulky, costly, and intermittent systems, CORVET provides unattended, multiday metabolic tracking with improved accuracy and minimal disruption to patient care. Its use of mixing chambers eliminates the need for expensive, fast sensors and precise synchronization required by breath-by-breath methods. Furthermore, it surpasses prior miniature systems by offering autonomous calibration and continuous operation without requiring manual intervention or interrupting ventilation, thereby providing critical, continuous metabolic data for tailored patient management.
Benefits
- Enables continuous, long-term, and accurate measurement of oxygen consumption (VO₂) and carbon dioxide production (VCO₂)
- Operates without disrupting patient ventilation, crucial for mechanically ventilated patients
- Reduces system cost by allowing the use of slower, less expensive gas sensors
- Autonomously detects and compensates for sensor calibration drift, ensuring reliability over extended periods
- Provides critical metabolic data (e.g., energy expenditure) to guide personalized nutritional and therapeutic interventions
- Features a compact design and versatile compatibility with various breathing apparatuses
Potential Use Cases
- Critical-care patient monitoring
- Personalized nutrition support
- Long-term metabolic tracking
- Ventilator patient management
- Metabolic research studies