Defective valve in a Venflon™ cannula

Dear Editor,

A woman presented for elective caesarean section. She had difficult venous access, but eventually a 16-G BD Venflon™ Pro Safety was sited in the left antecubital fossa. Attempts at spinal anaesthesia failed, so general anaesthesia was induced. Following injection of propofol and rocuronium through the injection port of the cannula, there was immediate reflux of blood. Although we were concerned that a quantity of the drugs had been lost, the patient appeared anaesthetised and paralysed; laryngoscopy and intubation were completed uneventfully. Blood continued to flow freely out of the closed injection port of the cannula, in spite of attempting to occlude the tip of the cannula through direct pressure. A second cannula was placed in the right hand, and the defective cannula was removed. The case continued without further incident.

There appeared to be a problem with the one-way valve in the injection port, which only leaked after the induction injections. The incident was explained to the patient, and reported locally in our hospital and to the MHRA.

The cannula was returned to BD for analysis; they found that the injection one-way valve had moved in the cannula hub, causing the problems that we experienced.

Christina McCarroll
ST7 Anaesthesia
Health Education North East 

Amir Rafi
Consultant Anaesthetist
University Hospital of North Durham 

BD have been contacted for a response

A reply from MHRA:

MHRA ref CSC 36607: MHRA is an arm’s-length government organisation responsible for overseeing the regulation of medical devices used in the UK. The regulatory system contributes to the overall need to protect public health and increase patient safety, while facilitating the safest access to medical devices used to treat and care for patients.

The MHRA noted a safety signal in November 2020 for the BD Venflon Pro Safety device, and in collaboration with the manufacturer we initiated a rapid investigation. The manufacturer subsequently found the cause for port leaks was an internal valve failure, and has revised procedures and implemented corrective actions for the manufacture of devices across their range of cannulae.

In our discussions with the manufacturer, we agreed the clinical imperative for these devices took precedence over the small risk of leaks occurring during use, even though they could pose a significant hazard should a leak occur. Therefore, the MHRA recommended the manufacturer should publish an advisory Field Safety Notice (FSN) to alert UK healthcare professionals of the potential problem. This publication included advice for them to follow when using these devices. The MHRA continues to work with the manufacturer while they implement their safety actions to remove this identified risk from the UK healthcare system. As is normal in such circumstances, we will actively monitor the situation and, if necessary, we will adapt our approach if any new information emerges which requires us to do this. To assist us in our endeavours, the MHRA would very much welcome reports of any further or similar incidents coming to the attention of the anaesthesia community. As always, we are extremely grateful to them for the fruitful collaboration we normally enjoy, as part of their well-recognised commitment to patient safety.