MAUDE Adverse Event Report: MISONIX, INC. NEXUS® STANDARD HANDPIECE; ULTRASONIC SURGICAL ASPIRATOR SYSTEM HANDPIECE

Model Number 100-21-0001

Device Problems Overheating of Device (1437); Use of Device Problem (1670)

Patient Problem Burn(s) (1757)

Event Date 02/09/2023

Event Type  malfunction  

Event Description

On march 6, 2023, misonix llc., a bioventus co., received a product occurrence report on a nexus® standard handpiece (part number 100-21-0001, serial number(b)(4)that occurred on (b)(6) 2023, during a l3 hemi-laminectomy while using a nexus bonescalpel macro hook shaver & tubeset (part number 110-31-1220).Specifically, the report indicated a patient grade 1 (first degree) burn to the patient's skin on right side of the incision.The surgeon stated the handpiece became hot during usage.Delay in treatment was not reported.Medical intervention required to preclude serious injury was not reported.Permanent impairment to body structure or body function was not reported.A misonix representative confirmed and the surgeon acknowledged that the surgical technique used was inconsistent with the instructions in the ifu.The surgeon rested the probe tip on the patient's skin.The ifu contains a warning that the protective silicone sleeve, included with certain probe tips such as part number 110-31-1220, reduces the risk of thermal damage but does not eliminate it.Contact with the silicone sleeve should be avoided or kept brief with minimal amount of contact pressure.Pressure and extended exposure can still result in excessive frictional heat and cause burns.The surgeon also stated the handpiece felt hotter than normal during use.The surgeon has neither provided additional information nor reported additional patient burn events since speaking with the representative.

Manufacturer Narrative

On(b)(6) 2023, misonix llc., a bioventus co., received a product occurrence report on a nexus® standard handpiece (part number 100-21-0001, serial number (b)(4) that occurred on (b)(6), 2023, during a l3 hemi-laminectomy while using a nexus bonescalpel macro hook shaver & tubeset (part number 110-31-1220).Specifically, the report indicated a patient grade 1 (first degree) burn to the patient's skin on right side of the incision.The surgeon stated the handpiece became hot during usage.Delay in treatment was not reported.Medical intervention required to preclude serious injury was not reported.Permanent impairment to body structure or body function was not reported.A misonix representative confirmed and the surgeon acknowledged that the surgical technique used was inconsistent with the instructions in the ifu.The surgeon rested the probe tip on the patient's skin.The ifu contains a warning that the protective silicone sleeve, included with certain probe tips such as part number 110-31-1220, reduces the risk of thermal damage but does not eliminate it.Contact with the silicone sleeve should be avoided or kept brief with minimal amount of contact pressure.Pressure and extended exposure can still result in excessive frictional heat and cause burns.The surgeon also stated the handpiece felt hotter than normal during use.The surgeon has neither provided additional information nor reported additional patient burn events since speaking with the representative.The device history record was reviewed for the nexus® standard handpiece, (part number 100-21-0001, serial number (b)(4) was reviewed.The handpiece was manufactured in accordance with the device master record.There were no deviations found during in-process or final inspection of the handpiece that would cause or contribute to a patient burn or user burn.Inspection and test results met specifications.The macro hook shaver and irrigation tubeset (part number 110-31-1220) is a sterile kit containing multiple component parts.The kit was not returned.The lot number for kit not included in the product occurrence report.The history record for the kit could not be reviewed.The customer returned one (1) titanium macro hook shaver probe (part number e4004abc40) that was used during the procedure.The returned part lot number was 00280422.A review of incoming inspection records for the subject probe indicated that the probe met all specification prior to release to kit assembly.The silicon sheath that is included in the kit, part number e4035abc07, was not returned.Evaluation of the sheath was not feasible.The returned handpiece, returned probe, and a new sheath were assembled and evaluated by engineering.The evaluation of the handpiece confirmed that the temperature of the rear housing (distal end relative to the patient), a part likely to be touched by the user, was above the upper tolerance specification.Root cause is indeterminant at the time of filing.The returned front housing and new sheath, parts likely to be applied to patient tissue, were within temperature specifications.A review of post-market surveillance data for the nexus® standard handpiece (part number 100-21-0001) and the nexus bonescalpel macro hook shaver & tubeset (part number 110-31-1220) did not show any significant adverse trends for user or patient burns.The current frequency of occurrence for patient burns is within the frequency originally estimated in the original risk management report.Therefore, there is no change to the residual risk or risk-benefit ratio.The instructions for use manual (100-10-1000, revision f) for the nexus® ultrasonic surgical aspiration system contains the following warnings and cautions regarding the surgical technique and device settings required to prevent thermal injury: potential burn hazard.Warning nexus® probes have a silicone or hard plastic sheath.Compressing or bending the sheath may cause the sheath to contact the vibrating surface along the length of the probe or at the probe tip and may cause excessive heating, which may burn user or patient tissue at the surgical site.Warning excessive loading of nexus® probes at the surgical site may induce heating due to vibration and friction as target tissue is fragmented and emulsified.It is critical to manage the temperature of the probe by adjusting the irrigation, aspiration, and ultrasound settings, and surgical technique.Tissue necrosis may result if probe tip is not moved relative to tissue.A continuous, lateral sweeping motion is recommended in order to minimize contact duration with the ultrasonic probe tip and minimize heat build-up.When lateral motion is not possible withdraw and re-insert probe tip frequently.Warning contact to vibrating elements like an extension and ultrasonic probe tip may cause burns and should be avoided by all means.The handpiece should only be held at the black handpiece housing area and/or the black hard sheath.Warning a protective silicone sleeve, included with certain probe tips, reduces the risk of thermal damage but does not eliminate it.Contact with the silicone sleeve should be avoided or kept brief with minimal amount of contact pressure.Pressure and extended exposure can still result in excessive frictional heat and cause burns.Warning contact of the rigid or silicone sheaths with patient tissue under pressure, may create a burn hazard.Avoid contact of sheath elements with patient tissue under pressure.Warning probe tip temperatures may exceed the tissue necrosis point if insufficient irrigant is present at the probe tip-tissue interface.For hard tissue removal, always use the maximum irrigation flowrate that does not affect the surgical field of view, or impact surgical technique.Additional external irrigation, e.G., by administering sterile saline with a syringe over the distal probe tip portion, may be necessary for removal of very dense, hard osseous structures.Warning hard tissue applications, a minimum irrigation setting of 20 is recommended to minimize or prevent thermal injury and/or tissue necrosis.Caution insufficient irrigation and high tip pressure (loading) under extended exposure, e.G., in tight cavities, are to be avoided while removing hard tissue.It is recommended to withdraw and re-insert the ultrasonic tips (e.G., blades & shavers) repeatedly to re-establish adequate cooling and lubrication.Caution additional external irrigation, e.G., by administering sterile saline with a syringe over the distal tip portion, may be necessary when removing very dense, hard osseous structures.Caution prime the irrigation tubing prior to use.At all times ensure that the irrigation flows towards the handpiece when footswitch is depressed.If no irrigation is flowing, cease use until flow is restored.

• Brand Name: NEXUS® STANDARD HANDPIECE
• Type of Device: ULTRASONIC SURGICAL ASPIRATOR SYSTEM HANDPIECE
• Manufacturer (Section D): MISONIX, INC.; 1938 new highway; farmingdale NY 11735
• Manufacturer (Section G): MISONIX, INC.; 1938 new highway; farmingdale NY 11735
• Manufacturer Contact: john salerno ; 1938 new highway; farmingdale, NY 11735 ; 6319279172
• MDR Report Key: 16697409
• MDR Text Key: 313261755
• Report Number: 2435119-2023-00006
• Device Sequence Number: 1
• Product Code: LFL
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K190610
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Other,User Facility
• Reporter Occupation: Non-Healthcare Professional
• Remedial Action: Replace
• Type of Report: Initial
• Report Date: 04/06/2023

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 04/06/2023
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: 100-21-0001
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 03/09/2023
• Date Manufacturer Received: 03/06/2023
• Was Device Evaluated by Manufacturer?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Unknown
• Patient Sequence Number: 1
• Patient Outcome(s): Other