Compatibility of tubing connectors and medical gas sources

Background

The TGA cautions users to select oxygen tubing connectors that are designed to provide a secure fit with medical gas outlets. Sponsors and manufacturers of connectors and outlets are advised to review and update instructions for correct use to minimise the risk of disconnection between connectors and gas outlets during use.

There is a wide range of medical devices that can connect to medical gas outlets. There are two connector types that these medical devices may use. These are;

• The firtree connector (on the right of Figure 1), which can only connect to firtree (also known as ‘nipple’) outlets
• The universal connector (on the left of Figure 1), which is designed to fit both screw thread and firtree outlets. Universal connectors have a section with a larger inner diameter to fit the wider screw thread outlet, and a second section with a smaller inner diameter to fit firtree outlets.  

Figure 1. Left: Universal Connector, Right: Firtree Connector

The TGA is aware that some universal connectors may not achieve a secure connection with some shorter firtree outlet designs. Firtree outlets are not fitted in the larger inner diameter section of tubing in universal connectors. Firtree outlets only achieve a secure fit in the second smaller inner diameter section of tubing. If the firtree outlet is too short, it will not reach this section of tubing for a long enough distance to provide a secure and reliable connection. An insecure connection can lead to the risk of tubing detaching from a medical gas source during use. This is a hazard to patients who are dependent on an oxygen supply, such as for ventilation or emergency resuscitation.

Actions for sponsors and manufacturers of oxygen connector tubing

The TGA has identified a risk associated with oxygen connector tubing because of increasing reports of device-related incidents concerning the emergence of shorter firtree gas outlets. All sponsors of devices with oxygen tubing that connect to medical gas outlets are required to review and update Instructions for Use (IFU) and relevant risk documents. These documents must guide users on the gas outlet connection type with which the device can be safely used and outline risk mitigations for tubing detachment.

Sponsors and manufacturers are required to review and update their IFUs to include:

• An outline of compatible medical gas outlet type(s) for their device.
• Instructions on how to attach the device to a compatible medical gas source.
• How to check for a secure connection.
• Warnings to users about the risk of poor connection between device and gas outlet.

The TGA also requires sponsors and manufacturers to review and update relevant risk documents to address the risks associated with tubing detachment.

The TGA requires all IFUs and relevant documents to be updated by 1 December 2023. The TGA will conduct a random audit of device IFUs and relevant documents after this date to ensure compliance with this advice.

Sponsors who claim compatibility with both screw thread and firtree outlets for the same device must hold evidence of compatibility with both outlets. This includes test evidence the device can securely fit firtree outlets with the minimum length specifications outlined in EN 13544-2 Respiratory therapy equipment - Part 2: Tubing and connectors.

Sponsors must hold, at all times, evidence of the device’s compliance to essential principles. This includes compliance to the relevant standards and specifications, and information such as test evidence that demonstrates the risk of tubing detachment has been minimised. The TGA is continuing to review and monitor safety signals and risk in this area.

Enquiries for this advice can be directed to medicaldevicesurveillance@health.gov.au.

Advisory for users and health professionals

If you use oxygen tubing for medical purposes, please ensure the following:

• Before use, check that the tubing is compatible with the relevant gas outlets and sources in your facility.
• Revise compatibility each time your connectors or medical gas source models are updated.
• Check the security of the fit. Before use with a patient, test gas flow at typical use pressures to ensure it does not cause tubing detachment.

Do not:

• Try to force tubing on to incompatible sources.
• Alter the tubing device.
• Use unapproved adapters
• Use tubing contrary to the IFU.

Reporting problems

The TGA encourages consumers and health professionals to report problems with medical devices.  Your report will contribute to the TGA's monitoring of these products. For more information see the TGA Incident Reporting and Investigation Scheme.

The TGA cannot give advice about an individual's medical condition. You are encouraged to talk with a health professional if you are concerned about a possible adverse event with a medical device.