Yasumi Maze

Silicone-coated polypropylene hollow-fiber oxygenator : Experimental evaluation and preliminary clinical use

BACKGROUND A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-microm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures. METHODS Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator. RESULTS Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O2 and CO2 transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability. CONCLUSIONS This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.

Clinical Experience with the Nikkiso Centrifugal Pump

The Nikkiso HPM-15 is a minimally sized centrifugal pump. Preliminary results regarding clinical use of this pump for cardiopulmonary bypass (CPB) procedures have been reported previously. Recently, we have managed some additional cases using a newly developed controller. This article reports our clinical experiences with the use of this pump. We have managed 23 cases with a Nikkiso centrifugal pump. Twenty-two patients underwent CPB and 1 patient with fulminant viral myocarditis underwent percutaneous cardiopulmonary support (PCPS). With this pump, the circuit was extremely easy to prepare and deaeration was achieved readily. Hemodynamics during CPB and PCPS were stable in all cases. The increase in serum-free hemoglobin levels during CPB with this pump was as low as that seen in preliminary tests. A decrease in the platelet count was observed after the initiation of CPB with this pump; however, platelet counts returned to preoperative values 7 days after surgery. Moreover, urine output during CPB with this pump was as high as that seen in preliminary tests. No abnormalities in renal or liver function occurred during CPB. It appears that this new centrifugal pump is safe and easy to operate, and we conclude that it is useful for CPB and PCPS.

Aggregatibacter aphrophilus infective endocarditis confirmed by broad-range PCR diagnosis: A case report

Highlights • Case of infective endocarditis caused by a rare pathogen, Aggregatibacter aphrophilus is presented.• Aggregatibacter aphrophilus can’t be detected by common culture methods.• Br-PCR testing is a useful tool to identify pathogens of culture negative endocarditis.• Serum PR3-ANCA can be positive in Aggregatibacter aphrophilus endocarditis.

Retrograde Ascending Dissection After Thoracic Endovascular Aortic Repair Combined With the Chimney Technique and Successful Open Repair Using the Frozen Elephant Trunk Technique

The chimney technique can be combined with thoracic endovascular aortic repair (TEVAR) to both obtain an appropriate landing zone and maintain blood flow of the arch vessels. However, surgical repair becomes more complicated if retrograde type A aortic dissection occurs after TEVAR with the chimney technique. We herein report a case involving a 73-year-old woman who developed a retrograde ascending dissection 3 months after TEVAR for acute type B aortic dissection. To ensure an adequate proximal sealing distance, the proximal edge of the stent graft was located at the zone 2 level and an additional bare stent was placed at the left subclavian artery (the chimney technique) at the time of TEVAR. Enhanced computed tomography revealed an aortic dissection involving the ascending aorta and aortic arch. Surgical aortic repair using the frozen elephant trunk technique was urgently performed. The patient survived without stroke, paraplegia, renal failure, or other major complications. Retrograde ascending dissection can occur after TEVAR combined with the chimney technique. The frozen elephant trunk technique is useful for surgical repair in such complicated cases.

Surgical Treatment for Aortic Surgery Using Antegrade Selective Cerebral Perfusion

当施設で経験した脳分離体外循環使用症例は40例で,年齢45～79歳(平均67.2±8.1),男性29例,女性11例であった.40例のうち,緊急症例は21例(緊急群),待機症例は19例(待機群)で,緊急群,待機群につき比較・検討を行った.術式は,緊急群では,上行置換術15例,弓部全置換術5例,弓部部分置換術1例,待機群では,上行置換術2例,弓部全置換術17例で,待機群は,弓部全置換術が多かった.また,選択的脳灌流時間のみ有意差をもって待機群が長かった.在院死亡は,緊急群5例(23.8%),待機群1例(5.2%)で,脳神経障害に関しては,一過性の脳神経障害は,緊急群1例,待機群3例で,永続性の脳神経障害は,緊急群1例,待機群1例であった.われわれは,可能なかぎり体外循環の体送血を順行性とし,一貫して順行性選択的脳分離体外循環を用いてきたが,良好な成績であった.