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It was reported that the customer had an 18yr old patient on cardiohelp 7.0 for va ecmo who clotted off his circuit/pump within 2-3 hrs of being on.His ptt was over 90 and act 227 leaving the operating room.Who then passed away due to this event as we could no longer flow and cpr was started.The belief is that he was in dic.A questionnaire to gain additional event information was provided to the customer but despite several attempts no additional feedback was received at this time.The affected product was investigated at the laboratory of the manufacturer with the following results: the visual inspection of the delivered hls module for damage was unremarkable.A noticeable feature was a bluish discoloration of the module.The complaint sample had already been pre-cleaned by the user, but there were still blood residues in many places on the product.The product has been extensively rinsed and cleaned.After a longer exposure time, all "visible" clots could be rinsed out.The cause of the bluish discoloration cannot be determined with certainty retrospectively.What is striking, however, is that the blue discoloration can be identified in places where various components are connected with uv adhesive.However, the affected areas do not show any leaks, which means that air ingress at the points can also be ruled out.There was no evidence of excessive clotting (neither before nor after cleaning) on the discolored areas compared to the remaining areas of the product.In summary, a correlation between the bluish discoloration and the clotting of the product is therefore very unlikely.The functional test was monitored / set using an external pressure gauge.The required range of 625-650mmhg was maintained or even partially exceeded at all times during the test.There were no further abnormalities during the 60-minute examination of the product.The final leak test with a temporary increase in pressure was carried out over a period of 5 minutes.The speed of the cardiohelp had to be increased to the maximum speed to achieve the pressure of 775-800mmhg.The flow dropped by 0.21 l/min over the 5 minutes.A possible explanation for the reduction in flow could be the bernoulli effect, which in turn can be explained by the bernoulli equation.This states that the pressure decreases when the flow rate increases - conversely, the pressure increases when the flow rate decreases, which is reflected in the measured values.The customer's problem description could not be reproduced/confirmed with the available technical investigation options.Furthermore a medical review of the provided event information and the laboratory investigation results was performed with the following outcome: the complaint narrative relates an event wherein an 18 year old patient was supported by cardiohelp and its accompanying accessory (hls set advanced 7.0).Approximately two to three hours after the initiation of veno-arterial (va) support, the hls set advanced 7.0 was fully thrombosed (i.E.As explained by the attending clinical staff).According to the narrative, the partial thromboplastin time (ptt) was greater than 90 seconds with an activated clotting time (act) of 227 seconds at the time of exit from the operating room (or).As a note, the patient was described as having received heparin before cannulation with a resulting act of 227 seconds.The narrative stated that the patient expired in response to the inability to reestablish supported blood flow subsequent to circuit clotting, despite the initiation of cardiopulmonary resuscitation (cpr) by the clinical/medical staff.The limited history of the patient includes presentation to the operating room with ongoing cpr.Ecmo was initiated in the operating room, which stabilized the patient.The prevailing persuasion by the clinical staff/attending clinician(s) was that the patient was subject to disseminated intravascular clotting (dic) and, possibly, liver failure.Dic is poorly characterized in the in the extracorporeal membrane oxygenation (ecmo) population with the underlying mechanisms not being clearly understood.That said, thrombotic complications are recognized in (b)(4) of patients on ecmo.Both bleeding and thrombotic complications are associated with increased mortality in this cohort of patients.Given the diagnosis of active dic, venous thrombosis (vt) or deep venous thrombosis (dvt) are possible complications of the syndrome.Vt or dvt may explain the presence of extensive thrombus in the hls set advanced as suction was applied to the venous aspect of the circulation via the hls set advanced.Further, inadequate/insufficient cpr may have promoted the formation of thrombus before the administration of heparin by the or staff.The history of the patient is not well described in the complaint narrative.Therefore, it is not known if there were predisposing factors contributing to thrombus formation or patient disposition.Further, other measures of (anti) coagulation were not disclosed in the narrative (e.G.Atiii, antixa, fibrinogen concentration, d-dimers, platelet count, etc.), which may present a challenging influence in determination of a root cause for the presence of thrombus.Outside of the single reported values of 227 seconds and 90 seconds for the act and pt, respectively, little is known about subsequent values for these parameters (i.E.Act and ptt) after the reported values in the complaint narrative.The conclusion of the laboratory investigation was inconclusive as the condition described in the narrative was not able to be duplicated/reproduced.As an aside, the bluish discoloration of the hls (set advanced) module (as cited in the investigation report) may be due to the administration of methylene blue (mb), which has been used as a rescue agent to increase vascular tone.However, mb may have the capacity to neutralize heparin, which may have contributed to the generation of venous thrombus.Given the paucity of available information related to the event, the lack of patient history, and the unclear details regarding the presentation of the patient to the or, it is challenging to assign the event occurrence to either mal-performance or a diminution in performance to the product.Further, a direct association between the unfortunate outcome of the patient and the performance of the product cannot be established barring more information from the customer.Thus, at this time the reported failure "circuit clotted off / no flow" could be confirmed but was most probable not associated or contributed by a product related malfunction.The exact root cause remains unknown.The customer will be informed about the investigation results via a getinge representative.If additional information becomes available at a later state the complaint investigation may be reassessed.The occurrence rate was calculated for the reported issue and it was determined that this is not a systemic issue.Therefore, no remedial action is required.The occurrence rate related to the reported issue is currently being monitored as part of maquet cardiopulmonary¿ s trending program and additional investigations or corrections will be implemented in case of adverse trending.
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