(b)(4).Device evaluation by manufacturer: a 13-month complaint history review and service history review for similar complaints was performed for serial (b)(4) from 07-may-2017 through aware date (b)(6) 2018.There were no similar tickets related to the reported event during the searched period.However, a 13-month complaint history on the biorad (br) control lot 33950 was performed and found that there were 3 complaints related to the reported event during the searched period.The g8 operator's manual under chapter 1, introductions and applications, states the following: the time from injection of the sample to the time the specific peak elutes off the column is called retention time.The tosoh automated glycohemoglobin analyzer hlc-723g8 software has been written so that each of the expected fractions has a window of acceptable retention times.If the designated peak falls within the expected window, the chromatogram peaks will be properly identified.When a peak elutes at a retention time not within a specified window, an unknown peak (p00) results.If more than one peak elutes at times not specified by the software windows, each is given a sequential p0x title.In order to keep the peaks within their appropriate windows, it may be necessary to change how fast or slow the buffers are moving through the system by changing the pump flow rate.Quality control: in order to monitor and evaluate the accuracy and precision of the analytical performance, controls should be assayed daily and after column replacement.Tosoh suggests running at least two levels of quality control material.The mean of one should be in the non-diabetic range (4-7% hba1c) with the second in the range of 9-12% hba1c.If the value of one or more control specimens is out of the acceptable range, recalibrate the system and rerun the controls before testing patient samples.Qc materials should be used in accordance with local, state, federal and accredited organizations.Controls should be diluted with hsi hemolysis and wash.The g8 variant analysis mode training manual under lesson 8 - troubleshooting, states the following: adjusting the flow rate - how and why on the tosoh automated glycohemoglobin analyzer hlc-723g8; variant analysis mode it may be necessary to adjust the flow rate because either unidentifiable peaks appear on all the chromatograms or the average retention time for various peaks has changed significantly.The flow rate is changed by changing the flow factor in the instrument.The flow factor is generally 1.00 ml/min.The flow factor should only be adjusted +/- 0.05 of the default factory setting.The most probable cause of the reported event was due to the retention time being out of range high, which was resolved by adjusting the flow factor.
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A customer reported that after replacing a high count column and calibrating quality controls (qc), the qc was running low with the g8 instrument.The customer reported that they were running biorad (br) lot 33950 for the qc material.Technical support (ts) found that the flow factor (ff) was 1.05 ml/min and the sa1c retention time (rt) was 0.65 minutes.The customer calibrated with calibrator lot zs7001.The customer checked the system for leaks but did not find any.The customer adjusted the ff to 1.12 ml/min and the sa1c rt was 0.60 minutes.The customer then made fresh calibrator and verified the calibrator assignment value on the calibrator bottles matched the calibrator pints in the analyzer to recalibrate.However, the control results were low.Ts instructed the customer to run five samples as primers and the sa1c dropped to 0.59 minutes.The customer then recalibrated and ran controls resulting in a normal range low control but the high control level was out of range high.When the customer repeated the controls, the control level was still high for level 2 at 10.4%.The customer reported that they were not running patient samples due to high control values.Ts then instructed the customer to adjust the flow rate to 1.09 ml/min and then recalibrate.When the customer recalibrated, the controls were in range for level 1-5.1% and level 2- 9.6%.The retention time was 0.60 minutes.The delay in reporting of patient results for hemoglobin a1c (hba1c) was due to quality controls being out of range.There is no indication of any patient intervention or adverse health consequences due to the delay in reporting of patient results.
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