Infusion Pumps Safety Assurance

The US Food and Drug Administration (FDA)’s guidance, entitled “Infusion Pumps Total Product Life Cycle” provides assistance to industry in preparing premarket submissions for infusion pumps and to identify device features that manufacturers should address throughout the total product life cycle. The document is limited to class II devices classified under the regulation, 21 CFR 880.5725, which includes devices with the product codes listed below

Safety Assurance Case

Infusion pump 510(k) submissions typically include changes or modifications to software, materials, design, performance, or other features compared to the predicate. Accordingly, FDA expects that most new devices (as well as most changed or modified devices) will have differences in technological characteristics from the legally marketed predicate device even if sharing the same intended use. Under section 513(i) of the Federal Food, Drug, and Cosmetic Act (the FD&C Act), determinations of substantial equivalence will rely on whether the information submitted, including appropriate clinical or scientific data, demonstrate that the new or modified device is as safe and effective as the legally marketed predicate device and does not raise different questions of safety and effectiveness in comparison to the predicate device.

  A. General Considerations for Safety Case Development

The three main elements of a safety assurance case are:

1. Claim: Statement about a property of the system or some subsystem.

2. Argument: Links the evidence to the claim

3. Evidence: Information that demonstrates the validity of the argument.

B. Hazard Analysis

The objective of the hazard analysis is to identify hazards and potential causes of the hazards.

  C. Performance Testing

Performance testing includes specific attention to statistical elements (hypotheses, analyses, sample size and sampling, power), controls, minimization of bias, test parameters (endpoints), follow-up, and evaluation criteria. The premarket notification (510(k)) should include the following information for all design verification performance testing activities submitted in support of safety case:

1. A description of the device design requirement being verified, including why it is essential to the proper functioning of the device;
2. A description of the unit under test and how it relates to the final, finished device;
3. The justification for the use of prototype or “production equivalent” devices or components during the design verification activity, if applicable;
4. An explicit statement of the acceptance criteria for the verification activity;
5. A detailed description of the verification method, including drawings and descriptions of the test apparatus where appropriate;
6. An explanation of how the verification test set up simulates actual clinical use conditions, if applicable;
7. The results of the verification activity;
8. An analysis of the verification activity results; and 9. An explicit statement of any conclusions drawn from the verification activity.

  D. Labeling

In addition to the labeling requirements in 21 CFR 801.109, including the prescription statement required under 21 CFR 801.109(b)(1), FDA recommends that the labeling contain the following information:

• Indications for use

• Cleaning and disinfection instructions for reusable infusion pumps and accessories.

• Alarm limits and ranges.

• Default settings.

• A complete representation of the user interface.

• An identification of any dedicated administration set or the specifications and/or specific models of infusion sets that are appropriate for use with this pump.

• Identify reservoir volume, selectable flow rates and profiles, and residual fluid volume remaining after the infusion is complete.

• Describe any factors that may affect flow accuracy such as ambient temperature, fluid temperature, pressure, fluid viscosity, or changes in flow rate or bolus delivery (e.g., such as when titrating medications).

• Define the accuracy specifications over the range of selectable flow rates and bolus volumes.

• Define the bolus delivery rate, if applicable.

• A description of the fluid(s) to be administered by the pump as indicated in the statement of intended use.

• Comprehensive directions for preparation and use for all functions of the device.

• Describe a method or methods that can be used to confirm that the device is in calibration for all relevant delivery features.

• Description of all alarm or information messages and recommended actions when alarms or information messages are provided.

• Warning statements on device regarding the safety of use during diagnostic procedures.

• Labeling should include all recommended information related to EMC, including reference to the appropriate standard, such as IEC 60601-1-2.

• For devices with RF wireless technology capabilities, the labeling should include information about the exact RF wireless technology incorporated or able to be used with the device.

• If the pump is designed to be used by individuals with specific disabilities, those disabilities should be described in the labeling.

  E. Alarms

In response to a hazardous situation, a pump may issue an alarm. Each alarm should be clearly indicated to the user. We recommend that the device meet the standards of IEC 60601-1-8: Medical electrical equipment – Part 1-8: General requirements for safety – Collateral standard: Alarm systems. Any risks of infusion delivery error associated with false positive alarms and false negative alarms should also be addressed.

  F. Safety Control Mechanisms

An infusion pump may have safety control mechanisms to prevent or detect hazardous situations. These may include, but are not limited to:

1. Power on self test (POST) checks – performed during pump startup or initialization;

2. Battery test;

3. Stuck key test;

4. Tone test;

5. Pump mechanism failure test;

6. Watchdog interrupt tests;

7. (Periodic) System checks – including a CPU test and ROM / RAM CRC tests;

8. Air detection sensors

9. Environmental monitoring sensors

10. Sensor checks – to check the proper functioning of sensors attached to the pump, if any; and 11. Dose error reduction checks.