Omni-DL Acute Dialysis System

The Transvivo Omni-DL Acute Dialysis System delivers continuous renal replacement therapies (CRRT) in a hospital ICU to congestive heart failure patients that have severe fluid overload and cardiac instability. The Omni-DL operation is controlled by a single board computer (SBC) and provides operator interface through a touchscreen LCD panel. The SBC interfaces to the system components through two USB data acquisition (DAQ) modules. The system utilizes a blood pump to circulate blood through a hemofilter and (3) fluid pumps to infuse premixed fluids from five-liter bags and to remove effluent from the hemofilter to a seven-liter waste bag. It monitors the operation of the fluid management using (4) pressure sensors and (3) load cells for bag volume measurement. It has a blood detector, an air detector and a pinch clamp to detect hazardous conditions and to stop flow if needed. It has numerous safety features to prevent injury to the patient and an alarm system to alert the operator. It has a battery backed power supply that allows for 30 minutes of operation during transport or power loss. Cooper Consulting Service (CCS) was the project leader for the development of the Omni-DL. The Omni-DL was designed and developed and received FDA approval in two years.

CCS performed the following engineering design and development functions during this project.

Documentation and project management

  • Developed project plan and periodically updated the plan over the course of the project
  • Developed the user requirements specification for the control unit and disposable kit
  • Developed the software requirements specification and software development plan
  • Developed the system design specification
  • Developed the software design specification and software architecture document
  • Developed the system verification and validation specification
  • Developed the risk management report and risk management file
  • Developed the Device Master Record
  • Performed the design reviews for each phase of the project
  • Held weekly conference call meetings that were documented as part of the design history record

System Hardware Design

  • Analyzed power requirements, selected medical grade AC/DC power supply and designed switching regulators to provide voltages to run the system
  • Analyzed requirements and selected single board computer and LCD with touchscreen controller
  • Designed pump motor control circuitry with servo control from encoder feedback.
  • Designed analog sensor interface circuitry for (4) pressure sensors, (3) load cells, (2) optical kit door detectors and pinch clamp position sensor
  • Designed digital sensor interface circuitry for blood detector and air detector
  • Designed bar code scanner interface circuitry
  • Designed EMC protection for all input and output connections.
  • Worked with industrial and mechanical design vendor to design and develop enclosure and caster base

Software Design

  • Designed CRRT therapy application to control and document the delivery of (4) therapy modes–CVVH, CVVHD, CVVHDF and SCUF
  • Designed graphical user interface (GUI) for operation and monitoring of the therapy operation
  • Developed a volume servo algorithm with load cell feedback for control of fluid balance during therapy
  • Developed an alarm system to activate audible and visual alerts and therapy shutdown under defined hazard conditions
  • Develped a workflow based system set up in the GUI for ease of system operation
  • Developed a multi-page GUI to provide separate pages for status, alarm, modification, operations and set-up operations
  • Developed diagnostic software for use in production testing and system check-out
  • Developed acceptance test software to perform semi-automated system test with documented report during final QA and system delivery
  • Developed automated and seff-documenting burn-in test for use during production

Disposable Tubing Kit Design

  • Worked with Transvivo mechanical engineers to design tubing kit layout
  • Worked with Transvivo mechanical engineers to design kit plates and interface to control system
  • Developed approach to semi-automated tubing kit installation on control system

Design Transfer and Production

  • Designed and fabricated test fixtures and wrote production test procedure
  • Transferred design to contract manufacturer and set-up production


  • Developed test plan for system
  • Performed moisture ingress testing and wrote test report
  • Worked with test laboratory to perform IEC 60601-1 2nd edition safety tests
  • Worked with test laboratory to perform EMC testing to qualify for CE mark