Udi - not required for product code.Implanted date: device was not implanted.Explanted date: device was not explanted.Occupation- clinical engineer.Pma/510(k)- k130520.The actual device was returned for product evaluation.Visual inspection upon receipt did not find a breakage or other anomaly in the appearance, which could lead to low gas exchange performance.The actual sample after rinsed and dried was tested for its gas exchange performance in accordance with the factory's inspection protocol.As a result, the obtained values met the factory specifications, and no anomalies were revealed.[bovine blood conditions] hb:12g/dl, temp.: 37°c., ph:7.4, svo2:65%, pvco2: 45mmhg; [circulation conditions] blood flow rate: 6l/min and 4l/min, v/q=1, fio2=100%; [o2 transfer volume]@6l/min= 380 ml/min.@4l/min= 274 ml/min; [co2 removal volume]@6l/min= 328 ml/min.@4l/min= 240 ml/min.Review of the provided pump record obtained the following findings: [about pco2]: 11:34, when first bg measurement was performed, paco2 was 53.5mmhg.The circulation condition was as follows.Blood flow rate was 4.5l/min and gas flow rate was 2.5 l/min.11:55, paco2 was 51.5mmhg and gas flow rate was 4l/min, which indicated decreasing paco2 in comparison with that measured at 11:34.13:21, paco2 was 31.3 mmhg.At this moment, gas was blown at 10l/min for over 15 minutes.From 13:53 onward, paco2 remained between 38.1 mmhg and 43.6mmhg.[about po2]: 11:34, pao2 was 320 mmhg.At this moment, fio2 was 70%.At 12:51 and 13:53, pao2 decreased to 100mmhg level.Fio2 was 70% from 11:34 to 13:53.As fio2 was not changed, it was not possible to read out the factors that caused the increase/decrease of pao2.After 14:22, when fio2 was increased to 100%, pao2 tended to increase.[other findings]: the temperature was reported to have dropped to around 20°c when circulating.However, no change in temperature could be confirmed from the pump records.It is unlikely that the co2 removal performance and oxygenation capacity could be improved if the performance of the oxygenator itself was compromised by any factor.From this, it was inferred that the condition of patient's blood might have contributed to this issue.Review of the manufacturing record and the product-release judgement record of the involved product/lot# combination confirmed there was no anomaly in them.A search of the complaint file found no similar report with the involved product code/lot# combination.From the investigation results, no anomaly was found in the gas exchange performance of the actual sample after rinsed and dried.The reason for the poor co2 removal performance was likely that the blood temperature was low, making it difficult to remove co2 (the lower the blood temperature, the more soluble the co2 is, that is the harder it is to remove).As for pao2, as it increased after fio2 was increased, it was presumed that svo2 decreased for some factors and pao2 decreased accordingly.However, the cause of occurrence could not be clarified.Ifu states: "[?]measure blood gases and make necessary adjustments as follows.A.Control pao2 by changing concentration of oxygen in ventilating gas using gas blender.To decrease pao2, decrease fio2.To increase pao2, increase fio2.B.Control paco2 by changing the total gas flow.To decrease paco2, increase total gas flow.To increase paco2, decrease total gas flow.(during perfusion).Upon patient rewarming, adjust o2 concentration, gas flow rate and blood flow rate by increasing them as needed based on an increase in patient's metabolism.Failure to adjust the gas supply and the blood flow rate appropriately may cause insufficient o2 supply needed or the amount of the patient's gaseous metabolism." (b)(4).
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