MAUDE Adverse Event Report: NIHON KOHDEN CORPORATION ZM-521PA; TRANSMITTER

Model Number ZM-521PA

Device Problems Overheating of Device (1437); Temperature Problem (3022)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 02/20/2018

Event Type  malfunction  

Manufacturer Narrative

The customer reported that the transmitter's case was warped next to the lower-right battery contact due to overheating.No other evidence of physical damage or fluid intrusion.Batteries were not given to the biomed.Slight deformation down by the lower right battery contact.When new batteries are inserted correctly, no immediate overheating and the unit powers on correctly.Qa evaluation revealed that the batteries required for this investigation were not returned.New batteries were inserted into the unit and heating could not be duplicated.Inspection of the negative contacts shows resin melting at the spring which per an nkc investigation on a similar incident is indicative of improper battery insertion.

Event Description

The customer reported that the transmitter's case was warped next to the lower-right battery contact due to overheating.

Manufacturer Narrative

Details of complaint: on (b)(6) 2018, customer at (b)(6) hospital reported the transmitter (zm-521pa sn: (b)(6)) had overheated.There was noted deformation of the case by the lower right battery contact.Service requested/performed: exchange.Investigation result: per nkc dhr, the unit has had no history of ncmr, deviation, or capa during manufacturing of the device.The device has not been refurbished and there were no discrepancies or unusual findings before device release that might relate to the reported issue.Review of device c4c history found no previously reported issues with the device after release to the customer.Qe evaluation of the device at nka was unable to duplicate the overheating upon proper insertion of the battery.The batteries required for the investigation were not returned.Inspection of the negative contacts show dents in the plastic above the spring which, per nkc investigation performed under (b)(4) on a similar incident, is indicative of incorrect battery insertion.The incorrect insertion of the battery causes the battery terminal spring to break the coating of the battery, leading to a short circuit.Measures to educate the customer on proper use of the batteries, including the recommended batteries, correct direction and insertion of battery, and on checking battery condition before use are addressed in the zm-520/530 series operator's manual.Customer is also advised to not allow the transmitter to continuously contact the patient's skin directly, as the transmitter heats up by 2 or 3 degrees c during normal operation, which may cause a low temperature burn to the patient.Possible gradual deterioration of the transmitter battery compartment should be detected upon performance of the recommended maintenance check every six months, in which the customer is advised to ensure that the battery cover, springs, and terminals in the battery compartment are not damaged or corroded.To highlight the importance of correct battery insertion, technical bulletins mtbex 047 issued 02/09/17, mtbex 052 issued 04/25/17, and mtbex 067 issued 03/2018 were created which reiterate the recommendation of the operator's manual.Mtbex 047 provides step by step instructions on how to properly insert the battery and mtbex 052 and mtbex 067 provides examples of correct and incorrect battery placement.Importance of proper battery insertion is also addressed through the zm telemeters skills lab offered at nk university.Design considerations for the potential hazards of improper battery insertion/short circuit include: (1) spring was designed to not damage battery coating upon forcible battery insertion.(2) structure designed to protect battery pole from contact with battery spring when inserted in reversed direction.(3) device designed to not cause overcurrent in case of short-circuit damage from fall, etc.Nkc conducted a test study to monitor temperature of the transmitter upon incorrect insertion of the battery.The results confirmed that the temperature at the exterior is at an acceptable level and has cleared safety standard iec 60601-1.Per hha #19-009, there have been a total of 132 "overheated" related calls life-to-date until 03/07/19.The total number of devices in distribution is (b)(4) for the zm-520 series and (b)(4) for the zm-530 series.The complaint rate is 0.52%.There have been no injuries or adverse patient events reported in association with the use of this device due to incorrect insertion of a battery.Assessment determined that in a worst case scenario, the probability of harm is "unlikely or remote" as the maximum exterior temperature (42.6 c) is below the minimum temperature (44 c) that can cause a burn after prolonged (greater than 5 hours) skin exposure.A new design change has been introduced to the transmitter rear case which would add an insulating sheet to prevent short circuit of the battery caused by incorrect battery insertion.The design change has been applied to the following serial numbers: zm-520pa - serial (b)(6) or later zm-521pa - serial (b)(6) or later zm-530pa - serial (b)(6) or later zm-531pa - serial (b)(6) or later additionally, for transmitters with serial numbers prior to the implementation range, the updated part (#6142902693 for zm-520 series, #6142902694 for zm-530 series) is available for rear case repair.Investigation conclusion: the root cause is determined to be transmitter design, not foreseeing the possibility of short circuit from incorrect insertion of the battery.Assessment determined that in a worst case scenario, the probability of harm is "unlikely or remote" as the maximum exterior temperature (42.6 c) is below the minimum temperature (44 c) that can cause a burn after prolonged (greater than 5 hours) skin exposure.A new design change has been introduced to the transmitter rear case which would add an insulating sheet to prevent short circuit of the battery caused by incorrect battery insertion.Corrected information: report number: incorrect mfr report number and importer report number: 81 corrected mfr report number and importer report number: 80 a1 patient identifier: incorrect #: (b)(6); corrected #: (b)(6).D4 model number: incorrect #: zm-531pa; corrected #: zm-521pa.D4 catalog number: incorrect #: zm-531pa; corrected #: zm-521pa.D4 serial number: incorrect sn: (b)(6); corrected sn: (b)(6).

Event Description

The customer reported that the transmitter's case was warped next to the lower-right battery contact due to overheating.

• Brand Name: ZM-521PA
• Type of Device: TRANSMITTER
• Manufacturer (Section D): NIHON KOHDEN CORPORATION; 1-31-4 nishiochia, shinjuku-ku; attn: shama mooman; tokyo, 161-8 560; JA 161-8560
• MDR Report Key: 7364160
• MDR Text Key: 103538253
• Report Number: 8030229-2018-00080
• Device Sequence Number: 1
• Product Code: DRT
• UDI-Device Identifier: 04931921115084
• UDI-Public: 4931921115084
• Combination Product (y/n): N
• PMA/PMN Number: K043517
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: user facility
• Type of Report: Initial,Followup
• Report Date: 01/27/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 03/22/2018
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: ZM-521PA
• Device Catalogue Number: ZM-521PA
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 02/27/2018
• Was the Report Sent to FDA?: Yes
• Date Report Sent to FDA: 01/27/2020
• Distributor Facility Aware Date: 01/22/2020
• Device Age: 29 MO
• Event Location: Hospital
• Date Report to Manufacturer: 01/27/2020
• Date Manufacturer Received: 01/22/2020
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1