It was reported that a valve is blocked.The reporter indicated that due to the ventricular enlargement, the surgeon tried pumping but it did not flow well.Thus, emergency replacement surgery was implemented.The pressure of the valve was not changed then.Since (b)(4) has been just replaced in november, the blockage might have been caused by (b)(4).Patient information was not provided.Additional information has been requested.
|
Additional data: d6: december 2017 (unknown day).Investigation: visual inspection: in the first step of our investigation, we will visually inspect the valve for defects.Permeability test: to prove the penetrability we have carried out penetrability tests.These test are carried out at a hydrostatic pressure of approximately 20-30 cmh2o in the direction of flow.Adjustment test: our adjustment tests are carried out with the standard prosa check-mate and measurement tool.The valve is adjusted from 0 to 40cm h2o and down again in increments of 4cm h2o.Braking force and brake function test: to measure the braking force, we tested the prosa valve with a braking force apparatus.Here it is measured how much force must be exerted on the housing to release the rotor to adjust the valve by the integrated magnet of the braking force apparatus.Results: first, we performed a visual inspection.No significant deformations or damage of the valve was detected during the visual inspection.However, the prosa valve housing was subsequently measure and indicated the present of a slight deformation.The housing deformation measured at -0.054mm, outside the tolerance of 0 +/- 0.02mm.Next, we tested the permeability, adjustability, and opening pressure of the valve, as well as the brake functionally and brake force.The prosa valve was permeable but could not be adjusted to all settings.Finally, we have dismantled the valves.Inside both valves, we have found a significant build-up of substances (likely protein).Based on our investigation, we confirm the presence of blockage in the prosa valve at the time of our investigation.This is likely due to the blockage inside the valves.As described in scientific literature, the problem encountered is one of the known, inevitable risks of hc-therapy by shunt implants.The cause of the deformation of the prosa valve could not be determined through our investigation.Significant outside pressure, for example by too much force from the prosa adjustment tool or by a fall or impact to the head of the patient, can compromise the integrity of the valve.We can exclude a defect at the time of release.The shunt system met all specifications of the final inspection when released from christoph miethke gmbh & co.Kg.
|