MAUDE Adverse Event Report: ATOS MEDICAL AB PROVOX BRUSH; AIRWAY DEVICE CLEANING BRUSH, INVASIVE

Catalog Number 7204

Device Problem Material Rupture (1546)

Patient Problem Foreign Body In Patient (2687)

Event Type  malfunction  

Manufacturer Narrative

Product return was not possible according to reporter, so this is a theoretical investigation based on complaint description, product-ifu and internal documents as well as accumulated technical experience from previous complaint investigations.The complaint report states that the brush head broke off inside the voice prosthesis but could be pulled out with a tweezers.The brush was used 3,5 weeks (which is ok according to manual).Further questions has been asked, but has not yet been answered, to understand the details of the event.A follow-up report will be compiled when more data are available.Discussion: the brush head of the provox brush consists of nylon filaments as bristles, twisted metal wire (diameter: 0.65mm, stainless steel) that is injection molded inside a pp plastic shaft or handle, and a pp-plastic tip on top of the brush head.A disconnect between the twisted metal and the shaft is very unlikely based on that the stainless steel wire is injection molded into the handle, experience and historical complaints.The most likely point of breakage is the actual twisted metal brush head that has been seen to break if bent extensively back and forth.This stainless steel wire has its breaking point at 758 n/mm^2 on average, making it very resilient to mechanical forces.It takes repeated damage to the material (such as bending it back and forth repeatedly) to weaken an subsequently break the material.The maximum forces applied to the brush during a cleaning procedure are at 13.7n (source: pf057-07, max.Esophageal flange strength).The chances of dislocating the voice prosthesis while cleaning are high when applying more than 13.7n of force.Therefore, the customer would have dislocated his vp before applying enough force to damage the brush by normal usage only.Furthermore, the average force needed to pull the brush head out of the brush handle is average 193n (stdev 18) for provox brush ref (b)(4) (internal reference (b)(4)).Taking all those facts in consideration, it is highly likely that the brush was damaged prior to usage as it is highly unlikely that the medical-grade steel wire broke during a standard cleaning procedure.The applied forces are just too small to damage steel.Conclusion/action: since no product return is available, we are not able to definitely determine the cause of the failure.The most likely root cause is the brush head has been bent several times back and forth, which is prohibited according to the ifu provox brush.The design of provox brush has recently been updated with a tpe-layer around the base of the metal wire to prevent it from being bent in that location reducing the strain on the wire.The design change was not deemed a safety enhancement and did not warrant a product recall.The lot number for this complaint is unknown and therefore also unknown if this was a product produced prior to the tpe update.

Event Description

This is the information that was received from the initial reporter: the patient was cleaning his voice prosthesis and the brush head snapped off inside the voice prosthesis and had to be removed with a tweezer.No effect on vp.Used brushes out of same pack and had no problem.Description of the product: provox brush is a device intended for cleaning of provox voice prosthesis in-situ.Cleaning is recommended twice a day and after each meal.

Manufacturer Narrative

This is a follow-up report (#1).Product return was not possible according to reporter.However we have received a photo of the actual handle of the product that has now been examined and added to the investigation.We have also received infomation about lot number.A few small corrections have also been made to this 3500a report -manufacturing date -event problem and evaluation codes-type of investigation.The complaint report states that the brush head broke off inside the voice prosthesis but could be pulled out with a tweezers.The brush was used 3,5 weeks (which is ok according to manual).No serious injury did occur but it could have if the event would reoccur.Investigation/discussion: the brush head of the provox brush consists of nylon filaments as bristles, twisted metal wire (diameter: 0.65mm, stainless steel) that is injection molded inside a pp plastic shaft or handle, and a pp-plastic tip on top of the brush head.A disconnect between the twisted metal and the shaft is very unlikely based on that the stainless steel wire is injection molded into the handle, experience and historical complaints.The most likely point of breakage is the actual twisted metal brush head that has been seen to break if bent extensively back and forth.This stainless steel wire has its breaking point at 758 n/mm^2 on average, making it very resilient to mechanical forces.It takes repeated damage to the material (such as bending it back and forth repeatedly) to weaken an subsequently break the material.The maximum forces applied to the brush during a cleaning procedure are at 13.7n (source: pf057-07, max.Esophageal flange strength).The chances of dislocating the voice prosthesis while cleaning are high when applying more than 13.7n of force.Therefore, the customer would have dislocated his vp before applying enough force to damage the brush by normal usage only.Furthermore, the average force needed to pull the brush head out of the brush handle is average 193n (stdev 18) for provox brush ref (b)(4) (internal reference (b)(4).-examination of a photo of the product shows that the pp-plastic surrounding the area where the wire of the brush head meets the handle shows deformation - dark spots in the photo.When the wire is bent it "pushes" the plastic material to the sides.This strongly suggests that the head of the provox brush has been bent, which is prohibited as stated in the ifu.Taking all those facts in consideration, it is highly likely that the brush was damaged prior to usage as it is highly unlikely that the medical-grade steel wire broke during a standard cleaning procedure.The applied forces are just too small to damage steel.Conclusion/action: since no product return is available, we are not able to definitely determine the cause of the failure.The most likely root cause is the brush head has been bent several times back and forth, which is prohibited according to the ifu provox brush.The design of provox brush has recently been updated with a tpe-layer around the base of the metal wire to prevent it from being bent in that location reducing the strain on the wire.The design change was not deemed a safety enhancement and did not warrant a product recall.

Event Description

This is the information that was received from the initial reporter: the patient was cleaning his voice prosthesis and the brush head snapped off inside the voice prosthesis and had to be removed with a tweezer.No effect on vp.Used brushes out of same pack and had no problem.Description of the product: provox brush is a device intended for cleaning of provox voice prostheses in-situ.Cleaning is recommended twice a day and after each meal.The voice prosthesis is seated in a puncture in the wall between esophagus and trachea.

• Brand Name: PROVOX BRUSH
• Type of Device: AIRWAY DEVICE CLEANING BRUSH, INVASIVE
• Manufacturer (Section D): ATOS MEDICAL AB; kraftgatan 8; hörby, 24235 ; SW 24235
• MDR Report Key: 11228620
• MDR Text Key: 228635203
• Report Number: 8032044-2021-00001
• Device Sequence Number: 1
• Product Code: LRC
• UDI-Device Identifier: 07331791000775
• UDI-Public: 7331791000775
• Combination Product (y/n): N
• PMA/PMN Number: EXEMPT
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative
• Type of Report: Initial,Followup
• Report Date: 01/08/2021

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 01/26/2021
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Lay User/Patient
• Device Catalogue Number: 7204
• Device Lot Number: 1910006
• Was Device Available for Evaluation?: No
• Date Manufacturer Received: 03/04/2021
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Outcome(s): Required Intervention