During the CPB, it was noticed that the patient flow (as measured by the Spectrum M4 flow probe) was significantly reduced (3.9 Lpm) comparative to pump flow at 6.0 Lpm. In addition, the Spectrum emboli counter was increasing incrementally. At first, this was thought to be due to flow probe positioning, but with further investigation transpires that a kink had developed at the reservoir outlet.
We concluded that the phenomena experienced was due to cavitation caused by this kink, possibly resulting in mal-perfusion and/or micro-emboli. No injury was caused to the patient.
No Injury
A sling was used to ensure no further kinking of the tubing.
COMPLAINT INFORMATION
Complaint #:
2023-00505
Date of Event:
Jan 24, 2023
Hospital:
ABERDEEN ROYAL INFIRMARY
Event Description:
The pump boot outlet kink was noticed during aseptic assembly. An unsuccessful attempt was made to correct this defect, resulting in cutting out of this section of tubing (no pictures taken). The circuit was then deemed adequate for clinical use and CPB was commenced. During the CPB, it was noticed that the patient flow (as measured by the Spectrum M4 flow probe) was significantly reduced (3.9 Lpm) comparative to pump flow at 6.0 Lpm. In addition, the Spectrum emboli counter was increasing incrementally. At first, this was thought to be due to flow probe positioning, but with further investigation transpires that an additional kink had developed at the reservoir outlet (see picture attached). We concluded that the phenomena experienced was due to cavitation caused by this kink, possibly resulting in mal-perfusion and/or micro-emboli. This incident has been reported via the hospital adverse events system (DATIX) and I assume the MHRA will be informed. Luckily, no injury was caused to the patient.
PRODUCT INFORMATION:
Product Number:
IN01728H
Product Descripti on:
ABERDEEN AD INSPIRE 8F
Serial/LOT Number
: 2210270110
Investi gati on Summary:
LivaNova received a report stating that during set up, the Customer noted that the section of tubing #0191061 SG XS with a length of 60cm corresponding to the reservoir outlet in the pump loop was kinked. 1 unit of PTS PN IN01728H, lot 2210270110. No patient/user affected. Pictures of thissue were provided by the customer, confirming the kink. The sample was not available for investigation. Manufacturing records have been verified to be conforming to specifications. From complaints database review, three further similar events have been recorded on this PTS pack code (See #2022-00391, #2022-01109 and #2022-06709). No other complaint was found reported for the concerned batch of 24 units of this lot. Based on the above, the root cause could betraced back to two factors: - a tie-band that pressed against the tubing in question, which during sterilization caused a permanent mark or deformation. - a tubing length selected by the customer which should be changed in a following revision, since it is not long enough, this generates a tension in the tubing during set-up and the procedure, which can generate the kink due to the initial material deformation caused by the tie bands pressing on the tubing. As mitigation action, the drawing of this involved PTS will be updated to revision no. 03 in March 2023 in order to add specific pictures to help the operator in the assembly phase of this involved line in the table pack. The aim of this action is to reduce operator error as far as possible. Therefore, all lots manufactured before the new drawing revision release, are pre-mitigation action implementation. LivaNova maintains and documents periodic customer events monitoring process in order to evaluate actions for products improvement.
Root Causes:
Based on the above, the root cause could be traced back to two factors: - a tie-band that pressed against the tubing in question, which during sterilization caused a permanent mark or deformation. - a tubing length selected by the customer which should be changed in a following revision, since it is not long enough, this generates a tension in the tubing during set-up and the procedure, which can generate the kink due to the initial material deformation caused by the ti e bands pressing on the tubing.
Corrective Actions:
As mitigation action, the drawing of this involved PTS will be updated to revision no. 03 in March 2023 in order to add specific pictures to help the operator in the assembly phase of this involved line in the table pack. The aim of this action is to reduce operator error as far as possible. Therefore, all lots manufactured before the new drawing revision release, are pre-mitigation action implementation. LivaNova maintains and documents periodic customer events monitoring process in order to evaluate actions for products improvement.
Best regards,
Customer Quality-Team
Complaints Handling # 2023-00505
Kind regards,
Marti n
Marti n Brunt
Territory Sales Manager (CP & ATS)
Cardiac Surgery Division
United Kingdom
It is interesting to note that as we monitor actual flow in the tube against the flow calculated by the roller pump it can show up this sort of problem highlighting the importance of inline monitoring.
As the kink is from a pre-connected circuit that has suffered a imposed memory in the packaging and deformed on bypass.
Tubing length has now been altered to mitigate this problem.