Udi - no required for the reported product code/lot number combination.The actual device was returned to the manufacturing facility for evaluation.Visual inspection upon receipt revealed no defects.The actual device, with the state upon receipt being kept, was built into a circuit with tubes.Saline solution was circulated in it and the pressure drop was determined at each flow rate.The pressure drop was found to be higher than that of the current product sample.Subsequently, the actual device was subjected to another visual inspection and revealed no clot formation.The actual device was fixed with glutaraldehyde solution and the housing component was removed for further inspection of the inside of the oxygenator module.No clot formation was revealed.The state of the fiber winding was confirmed to be normal.The fiber layer was removed from the winding in increments of 2 mm and each layer was subjected to visual inspection.There was no visible clot formation on the fiber winding.The outer cylinder was removed from the heat exchanger module and the inside of the heat exchanger module was subjected to visual and magnifying inspections.Red and white thrombi were found to have formed on and between the grooves.The fiber layers removed during the above test were inspected under magnification.Formation of red thrombus was found.Electron microscopic inspection of the fiber on each layer on the upper side of the fiber winding obtained in the above test revealed the adhesion of red blood cells, deformed red blood cells (echinocyte) and blood platelets.The clots adhering to the heat exchanger module was collected and inspected under electron microscope.The adhesion of red blood cells and blood platelets and the formation of fibrin net were found.The involved pump record was reviewed as follows.At the initiation of the circulation at 1:32, the arterial blood pressure was 147 mmhg with the arterial blood temperature at 30 degrees celsius.The arterial blood pressure was at 11:44 was found to have been raised up to 404 mmhg.A review of the device history record and shipping inspection record from the reported product code/lot number combination was conducted with no relevant findings.A search of the complaint file found no other report with the involved product code/lo number combination.During the evaluation of the actual device, the formation of thrombus on the fiber, the formation of white thrombus on the heat exchanger module were noted.As a cause of this complaint, based on the findings of small amount of echinocyte and fibrin net formed on the device, as well as the formation of white thrombus on the heat exchanger module, cold agglutination, accompanied with the formation of white thrombus, may have occurred around the heat exchanger module, resulting in obstruction in the actual device.From the available information, however, the definitive cause cannot be determined.(b)(4).All available information has been placed on file in quality assurance at the manufacturing facility for appropriate tracking, trending and follow-up.
|