Approximately from a month, staff in the diabetes clinic noted that the point-of-care testing (poct) hemoglobin a1c results appeared lower than would be clinically expected when run on the dca vantage analyzer.This determination was based off the patient report of self-management, their prior hemoglobin a1c history and reviewing a 90 day report of their continuous glucose monitor, dexcom.The occurrences of the problem were reported to the diabetes clinical nurse specialist and a table was created to evaluate for any trends or patterns.The suspicious results occurred regardless if the test was performed by different lot numbers, machines or instrument operators.The suspicious results appeared lower than clinically anticipated, not higher.The laboratory department was consulted and the team has been in frequent communication to discuss the issue.The avenues explored include: the device manufacturer (siemens) was consulted by the laboratory to determine if any concerns had been reported nationwide.Per siemens, there has not been any official concerns reported.The diabetes clinical nurse specialist called customer support for dexcom to determine if there had been any reports of their values running higher than usual (thus skewing the clinician¿s view of the average blood sugar numbers over the last 90 days).Per dexcom customer support, there has not been any official concerns reported.The air filters in the dca vantage analyzer were changed per the guidance of siemens.All instrument operators who perform poct hemoglobin a1cs were observed for proper collection technique.Their procedure was correct according to manufacturer instructions for use (¿ifu¿).Storage of materials were discussed and practice occurs according to manufacturer ifu.Forty paired samples were completed to ensure comparability among the dca vantage analyzers.Two samples were collected on each patient and run through two of the three available dca vantage analyzers.While there were a few outliers, the results were relatively comparable between the analyzers.When opportune, a lab sample was collected on patients whose point-of-care testing (poct) hemoglobin a1c was clinically suspicious.This was either done in our hospital-based lab (who also uses a dca vantage analyzer but using a venous sample vs.Capillary sample) or an outside lab using reference lab comparison (high-performance liquid chromatography (hplc) which is considered gold standard for hemoglobin a1cs).There have been five samples of this.Four of them have resulted in very similar results, with one being one percentage difference (7.1% vs.8.1%).While the occurrences appear to be anecdotally less frequent, there are still encounters that demonstrate a poct hemoglobin a1c result that appears suspiciously low for the clinical picture.The diabetes clinical team in an affiliated hospital has also noted several incidents where this is occurring at their clinical site.The collection technique was observed by the diabetes clinical nurse specialist and it was completed according to manufacturer ifu.The instrument operator did note that the control fluids in the morning quality control test were running lower than they had been previously (last month they ran at 5%, whereas this month they are running closer to 4%).This is concerning when there is limited blood glucose data, especially in the clinic¿s patients with type 2 diabetes.In these instances, our poct hemoglobin a1c result can determine a treatment plan (for example, to initiate insulin or not).The current plan of the team is for the providers to review their clinic visits ahead of time and determine which patients may need to have a lab drawn hemoglobin a1c versus a poct hemoglobin a1c.Manufacturer response for point of care testing - aic, siemens (per site reporter).Requested air cleaning and changing air filter.This did not help.
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