The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform

Shinji Kawahito - One of the best experts on this subject based on the ideXlab platform.

  • development of silicone rubber hollow fiber Membrane Oxygenator for ecmo
    Artificial Organs, 2003
    Co-Authors: Tadashi Motomura, Koshiro Sato, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Toshiyuki Shinohara, Yoichiro Kawaguchi
    Abstract:

    Silicone rubber hollow fiber Membrane produces an ideal gas exchange for long-term ECMO due to nonporous characteristics. The extracapillary type silicone rubber ECMO Oxygenator having an ultrathin hollow fiber Membrane was developed for pediatric application. The test modules were compared to conventional silicone coil-type ECMO modules. In vitro experiments demonstrated a higher O 2 and CO 2 transfer rate, lower blood flow resistance, and less hemolysis than the conventional silicone coil-type modules. This Oxygenator was combined with the Gyro C1E3 centrifugal pump, and three ex vivo experiments were conducted to simulate pediatric V-A ECMO condition. Four day and 6 day experiments were conducted in cases 1 and 2, respectively. Case 3 was a long-term experiment up to 2 weeks. No plasma leakage and stable gas performances were achieved. The plasma free hemoglobin was maintained within a normal range. This compact pump-Oxygenator system in conjunction with the Gyro C1E3 centrifugal pump has potential for a hybrid total ECMO system.

  • extracorporeal Membrane Oxygenator compatible with centrifugal blood pumps
    Artificial Organs, 2002
    Co-Authors: Tadashi Motomura, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Ikuya Nishimura, Toshiyuki Shinohara, Daniel Oestmann
    Abstract:

    : Coil-type silicone Membrane Oxygenators can only be used with roller blood pumps due to the resistance from the high blood flow. Therefore, during extracorporeal Membrane oxygenation (ECMO) treatment, the combination of a roller pump and an Oxygenator with a high blood flow resistance will induce severe hemolysis, which is a serious problem. A silicone rubber, hollow fiber Membrane Oxygenator that has a low blood flow resistance was developed and evaluated with centrifugal pumps. During in vitro tests, sufficient gas transfer was demonstrated with a blood flow less than 3 L/min. Blood flow resistance was 18 mm Hg at 1 L/min blood flow. This Oxygenator module was combined with the Gyro C1E3 (Kyocera, Japan), and veno-arterial ECMO was established on a Dexter strain calf. An ex vivo experiment was performed for 3 days with stable gas performance and low blood flow resistance. The combination of this Oxygenator and centrifugal pump may be advantageous to enhance biocompatibility and have less blood trauma characteristics.

  • development of a new hollow fiber silicone Membrane Oxygenator for ecmo the recent progress
    Annals of Thoracic and Cardiovascular Surgery, 2002
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Julie Glueck, Yukihiko Nose
    Abstract:

    : Throughout the last 50 years, many improvements have been made for a more effective Oxygenator. A large plate type Membrane Oxygenator, used by Clowes, and a coil type, used by Kolff, has evolved into the small hollow fiber Oxygenator. The complex bubble Oxygenator, or rotating disk Oxygenator, has become a small disposable bubble Oxygenator. The currently available Oxygenators are extremely small, efficient, and can be used for extended periods of time. However, there are some problems with extracorporeal Membrane oxygenation (ECMO). Currently in the United States, there are no clinically applicable hollow fiber ECMO Oxygenators available, in spite of the extended ECMO application. Therefore, the development of a small, yet efficient, silicone hollow fiber Membrane Oxygenator for long-term ECMO usage was attempted. Based on the results of many experimental models, preclinical Oxygenator models for long-term ECMO were developed in our laboratory using an ultra-thin silicone rubber hollow fiber Membrane.

  • preclinical evaluation of a new hollow fiber silicone Membrane Oxygenator for pediatric cardiopulmonary bypass ex vivo study
    Annals of Thoracic and Cardiovascular Surgery, 2002
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Tomohiro Maeda, Seiji Ichikawa, Masaki Kawamura, Kenji Nonaka, Joerg Linneweber, T Takano, Shuji Haraguchi, Hiroshi Ishitoya
    Abstract:

    Based on the results of many experimental models, a hollow fiber silicone Membrane Oxygenator applicable for long-term extracorporeal Membrane oxygenation (ECMO) was developed. For further high performance and antithrombogenicity, this preclinical model was modified, and a new improved Oxygenator was successfully developed. In addition to ECMO application, the superior biocompatibility of silicone must be advantageous for pediatric cardiopulmonary bypass (CPB). An ex vivo short-term durability test for pediatric CPB was performed using a healthy miniature calf for six hours. Venous blood was drained from the left jugular vein of a calf, passed through the Oxygenator and infused into the left carotid artery using a Gyro C1E3 centrifugal pump. For six hours, the O 2 and CO2 gas transfer rates were maintained around 90 and 80 ml/min at a blood flow rate of 2 L/min and V/ Q=3, respectively. The plasma free hemoglobin was maintained around 5 mg/dl. These data suggest that this newly improved Oxygenator has superior efficiency, less blood trauma, and may be suitable for not only long-term ECMO but also pediatric CPB usage. (Ann Thorac Cardiovasc Surg 2002; 8: 7‐11)

  • gas transfer performance of a hollow fiber silicone Membrane Oxygenator ex vivo study
    Artificial Organs, 2001
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Julie Glueck, Tomohiro Maeda, Seiji Ichikawa, Kenji Nonaka, Joerg Linneweber, T Takano, Minoru Mikami, Koshiro Sato
    Abstract:

    Based on the results of in vitro studies of many experimental models, a silicone hollow fiber Membrane Oxygenator for pediatric cardiopulmonary bypass (CPB) and extracorporeal Membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber with a 300 microm outer diameter and a wall thickness of 50 microm. In this study, we evaluated the gas transfer performance of this Oxygenator simulating pediatric CPB and ECMO conditions. Two ex vivo studies in a pediatric CPB condition for 6 h and 5 ex vivo studies in an ECMO condition for 1 week were performed with venoarterial bypass using healthy calves. At a blood flow rate of 2 L/min and V/Q = 4 (V = gas flow rate, Q = blood flow rate) (pediatric CPB condition), the O2 and CO2 gas transfer rates were maintained at 97.44 ± 8.88 (mean ± SD) and 43.59 ± 15.75 ml/min/m 2 , respectively. At a blood flow rate of 1 L/min and V/Q = 4 (ECMO condition), the O2 and CO2 gas transfer rates were maintained at 56.15 ± 8.49 and 42.47 ± 9.22 ml/min/m 2 , respectively. These data suggest that this preclinical silicone Membrane hollow fiber Oxygenator may be acceptable for both pediatric CPB and long-term ECMO use.

Tadashi Motomura - One of the best experts on this subject based on the ideXlab platform.

  • development of silicone rubber hollow fiber Membrane Oxygenator for ecmo
    Artificial Organs, 2003
    Co-Authors: Tadashi Motomura, Koshiro Sato, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Toshiyuki Shinohara, Yoichiro Kawaguchi
    Abstract:

    Silicone rubber hollow fiber Membrane produces an ideal gas exchange for long-term ECMO due to nonporous characteristics. The extracapillary type silicone rubber ECMO Oxygenator having an ultrathin hollow fiber Membrane was developed for pediatric application. The test modules were compared to conventional silicone coil-type ECMO modules. In vitro experiments demonstrated a higher O 2 and CO 2 transfer rate, lower blood flow resistance, and less hemolysis than the conventional silicone coil-type modules. This Oxygenator was combined with the Gyro C1E3 centrifugal pump, and three ex vivo experiments were conducted to simulate pediatric V-A ECMO condition. Four day and 6 day experiments were conducted in cases 1 and 2, respectively. Case 3 was a long-term experiment up to 2 weeks. No plasma leakage and stable gas performances were achieved. The plasma free hemoglobin was maintained within a normal range. This compact pump-Oxygenator system in conjunction with the Gyro C1E3 centrifugal pump has potential for a hybrid total ECMO system.

  • extracorporeal Membrane Oxygenator compatible with centrifugal blood pumps
    Artificial Organs, 2002
    Co-Authors: Tadashi Motomura, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Ikuya Nishimura, Toshiyuki Shinohara, Daniel Oestmann
    Abstract:

    : Coil-type silicone Membrane Oxygenators can only be used with roller blood pumps due to the resistance from the high blood flow. Therefore, during extracorporeal Membrane oxygenation (ECMO) treatment, the combination of a roller pump and an Oxygenator with a high blood flow resistance will induce severe hemolysis, which is a serious problem. A silicone rubber, hollow fiber Membrane Oxygenator that has a low blood flow resistance was developed and evaluated with centrifugal pumps. During in vitro tests, sufficient gas transfer was demonstrated with a blood flow less than 3 L/min. Blood flow resistance was 18 mm Hg at 1 L/min blood flow. This Oxygenator module was combined with the Gyro C1E3 (Kyocera, Japan), and veno-arterial ECMO was established on a Dexter strain calf. An ex vivo experiment was performed for 3 days with stable gas performance and low blood flow resistance. The combination of this Oxygenator and centrifugal pump may be advantageous to enhance biocompatibility and have less blood trauma characteristics.

  • development of a new hollow fiber silicone Membrane Oxygenator for ecmo the recent progress
    Annals of Thoracic and Cardiovascular Surgery, 2002
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Julie Glueck, Yukihiko Nose
    Abstract:

    : Throughout the last 50 years, many improvements have been made for a more effective Oxygenator. A large plate type Membrane Oxygenator, used by Clowes, and a coil type, used by Kolff, has evolved into the small hollow fiber Oxygenator. The complex bubble Oxygenator, or rotating disk Oxygenator, has become a small disposable bubble Oxygenator. The currently available Oxygenators are extremely small, efficient, and can be used for extended periods of time. However, there are some problems with extracorporeal Membrane oxygenation (ECMO). Currently in the United States, there are no clinically applicable hollow fiber ECMO Oxygenators available, in spite of the extended ECMO application. Therefore, the development of a small, yet efficient, silicone hollow fiber Membrane Oxygenator for long-term ECMO usage was attempted. Based on the results of many experimental models, preclinical Oxygenator models for long-term ECMO were developed in our laboratory using an ultra-thin silicone rubber hollow fiber Membrane.

  • preclinical evaluation of a new hollow fiber silicone Membrane Oxygenator for pediatric cardiopulmonary bypass ex vivo study
    Annals of Thoracic and Cardiovascular Surgery, 2002
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Tomohiro Maeda, Seiji Ichikawa, Masaki Kawamura, Kenji Nonaka, Joerg Linneweber, T Takano, Shuji Haraguchi, Hiroshi Ishitoya
    Abstract:

    Based on the results of many experimental models, a hollow fiber silicone Membrane Oxygenator applicable for long-term extracorporeal Membrane oxygenation (ECMO) was developed. For further high performance and antithrombogenicity, this preclinical model was modified, and a new improved Oxygenator was successfully developed. In addition to ECMO application, the superior biocompatibility of silicone must be advantageous for pediatric cardiopulmonary bypass (CPB). An ex vivo short-term durability test for pediatric CPB was performed using a healthy miniature calf for six hours. Venous blood was drained from the left jugular vein of a calf, passed through the Oxygenator and infused into the left carotid artery using a Gyro C1E3 centrifugal pump. For six hours, the O 2 and CO2 gas transfer rates were maintained around 90 and 80 ml/min at a blood flow rate of 2 L/min and V/ Q=3, respectively. The plasma free hemoglobin was maintained around 5 mg/dl. These data suggest that this newly improved Oxygenator has superior efficiency, less blood trauma, and may be suitable for not only long-term ECMO but also pediatric CPB usage. (Ann Thorac Cardiovasc Surg 2002; 8: 7‐11)

  • gas transfer performance of a hollow fiber silicone Membrane Oxygenator ex vivo study
    Artificial Organs, 2001
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Julie Glueck, Tomohiro Maeda, Seiji Ichikawa, Kenji Nonaka, Joerg Linneweber, T Takano, Minoru Mikami, Koshiro Sato
    Abstract:

    Based on the results of in vitro studies of many experimental models, a silicone hollow fiber Membrane Oxygenator for pediatric cardiopulmonary bypass (CPB) and extracorporeal Membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber with a 300 microm outer diameter and a wall thickness of 50 microm. In this study, we evaluated the gas transfer performance of this Oxygenator simulating pediatric CPB and ECMO conditions. Two ex vivo studies in a pediatric CPB condition for 6 h and 5 ex vivo studies in an ECMO condition for 1 week were performed with venoarterial bypass using healthy calves. At a blood flow rate of 2 L/min and V/Q = 4 (V = gas flow rate, Q = blood flow rate) (pediatric CPB condition), the O2 and CO2 gas transfer rates were maintained at 97.44 ± 8.88 (mean ± SD) and 43.59 ± 15.75 ml/min/m 2 , respectively. At a blood flow rate of 1 L/min and V/Q = 4 (ECMO condition), the O2 and CO2 gas transfer rates were maintained at 56.15 ± 8.49 and 42.47 ± 9.22 ml/min/m 2 , respectively. These data suggest that this preclinical silicone Membrane hollow fiber Oxygenator may be acceptable for both pediatric CPB and long-term ECMO use.

Koshiro Sato - One of the best experts on this subject based on the ideXlab platform.

  • development of silicone rubber hollow fiber Membrane Oxygenator for ecmo
    Artificial Organs, 2003
    Co-Authors: Tadashi Motomura, Koshiro Sato, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Toshiyuki Shinohara, Yoichiro Kawaguchi
    Abstract:

    Silicone rubber hollow fiber Membrane produces an ideal gas exchange for long-term ECMO due to nonporous characteristics. The extracapillary type silicone rubber ECMO Oxygenator having an ultrathin hollow fiber Membrane was developed for pediatric application. The test modules were compared to conventional silicone coil-type ECMO modules. In vitro experiments demonstrated a higher O 2 and CO 2 transfer rate, lower blood flow resistance, and less hemolysis than the conventional silicone coil-type modules. This Oxygenator was combined with the Gyro C1E3 centrifugal pump, and three ex vivo experiments were conducted to simulate pediatric V-A ECMO condition. Four day and 6 day experiments were conducted in cases 1 and 2, respectively. Case 3 was a long-term experiment up to 2 weeks. No plasma leakage and stable gas performances were achieved. The plasma free hemoglobin was maintained within a normal range. This compact pump-Oxygenator system in conjunction with the Gyro C1E3 centrifugal pump has potential for a hybrid total ECMO system.

  • gas transfer performance of a hollow fiber silicone Membrane Oxygenator ex vivo study
    Artificial Organs, 2001
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Julie Glueck, Tomohiro Maeda, Seiji Ichikawa, Kenji Nonaka, Joerg Linneweber, T Takano, Minoru Mikami, Koshiro Sato
    Abstract:

    Based on the results of in vitro studies of many experimental models, a silicone hollow fiber Membrane Oxygenator for pediatric cardiopulmonary bypass (CPB) and extracorporeal Membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber with a 300 microm outer diameter and a wall thickness of 50 microm. In this study, we evaluated the gas transfer performance of this Oxygenator simulating pediatric CPB and ECMO conditions. Two ex vivo studies in a pediatric CPB condition for 6 h and 5 ex vivo studies in an ECMO condition for 1 week were performed with venoarterial bypass using healthy calves. At a blood flow rate of 2 L/min and V/Q = 4 (V = gas flow rate, Q = blood flow rate) (pediatric CPB condition), the O2 and CO2 gas transfer rates were maintained at 97.44 ± 8.88 (mean ± SD) and 43.59 ± 15.75 ml/min/m 2 , respectively. At a blood flow rate of 1 L/min and V/Q = 4 (ECMO condition), the O2 and CO2 gas transfer rates were maintained at 56.15 ± 8.49 and 42.47 ± 9.22 ml/min/m 2 , respectively. These data suggest that this preclinical silicone Membrane hollow fiber Oxygenator may be acceptable for both pediatric CPB and long-term ECMO use.

  • preclinical evaluation of a hollow fiber silicone Membrane Oxygenator for extracorporeal Membrane Oxygenator application
    Asaio Journal, 2000
    Co-Authors: Tomohiro Maeda, Shinji Kawahito, Akinori Iwasaki, Kinichi Nakata, Kenji Nonaka, Joerg Linneweber, Sebastian Schulteeistrup, T Takano, Masaharu Yoshikawa, Koshiro Sato
    Abstract:

    A silicone Membrane hollow fiber Oxygenator applicable for use as an extracorporeal Membrane Oxygenator (ECMO) has been developed in our laboratory. This silicone hollow fiber displays astonishing mechanical stability, is barely compressible or stretchable, and assembles easily while maintaining good gas permeability. The priming volume is 140 cc with a surface area of 0.8 m 2 . This study evaluated the gas transfer performances and biocompatibility of the Oxygenator under ECMO and CPB conditions. In vitro studies that were performed at a blood flow rate of 2 L/min, and revealed O 2 and CO 2 gas transfer rates of 82.35 ± 0.56 ml/m 2 /L/min and 38.72 ± 2.88 ml/m 2 /L/min, respectively. The commercially available Kolobow (Avecor 1500) Oxygenator was used as the control, and had O 2 and CO 2 gas transfer rates of 53.8 ± 0.5 ml/m 2 /L/min and 24.7 ± 2.0 ml/m 2 /L/min. To evaluate blood trauma, Normalized Index of Hemolysis (NIH) was measured according to American Society of Testing and Materials (ASTM) standards. The NIH findings were 0.0112 g/100L at a blood flow of 1 L/min, and 0.0152 g/100L at 5 L/min. Three ex vivo experiments, using a blood flow rate of 1 L/min, were performed with venoarterial bypass, and O 2 transfer rate and CO 2 transfer rate of the Oxygenators were well maintained. This indicates that this preclinical silicone Membrane hollow fiber Oxygenator has superior efficiency, less blood trauma, and is smaller when compared with the only clinically available Kolobow Oxygenator.

  • development of a silicone hollow fiber Membrane Oxygenator for ecmo application
    Asaio Journal, 1998
    Co-Authors: Shingo Yamane, Koshiro Sato, Akinori Sueoka, Yukio Ohashi, Jiro Kuwana, Yukihiko Nose
    Abstract:

    : A new silicone hollow fiber Membrane Oxygenator for extracorporeal Membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber, with a 300 microm outer diameter and a wall thickness of 50 microm. The hollow fibers were mechanically cross-wound on the flow distributor to achieve equal distribution of blood flow without changing the fiber shape. The housing, made of silicone coated acryl, was 236 mm long with an inner diameter of 60 mm. The surface area was 1.0 m2 for prototype 211, and 1.1 m2 for prototype 209. The silicone fiber length was 150 mm, and the silicone Membrane packing density was 43% for prototype 211 and 36% for prototype 209. Prototype 211 has a priming volume of 208 ml, and prototype 209 has a priming volume of 228 ml. The prototype 211 Oxygenator demonstrates a gas transfer rate of 120 +/- 5 ml/min (mean +/- SD) for O2 and 67 +/- 12 ml/min for CO2 under 2 L of blood flow and 4 L of O2 gas flow. Prototype 209 produced the same values. The blood side pressure drop was low compared with the silicone sheet Oxygenator (Avecor, 1500ECMO). These results showed that this new Oxygenator for ECMO had efficiency similar to the silicone sheet Oxygenator that has a 50% larger surface area. These results suggest that the new generation Oxygenator using an ultrathin silicone hollow fiber possesses sufficient gas transfer performance for long-term extracorporeal lung support.

  • development of a Membrane Oxygenator for ecmo using a novel fine silicone hollow fiber
    Asaio Journal, 1996
    Co-Authors: Akio Funakubo, Tetsuya Higami, Ichiro Sakuma, Yasuhiro Fukui, Tsuyoshi Kawamura, Koshiro Sato, Akinori Sueoka, Yukihiko Nose
    Abstract:

    : One of the limitations of conventional silicone hollow fiber Oxygenators compared with microporous Membrane Oxygenators is poor gas permeability. However, the silicone hollow fiber is free from plasma leakage, which is the major life limiting factor of the microporous Membrane Oxygenator. It has been difficult to fabricate a fine, thin hollow fiber for reduction of resistance to gas permeability because of the poor mechanical strength of conventional silicone materials. The authors developed a novel silicone material with sufficient mechanical strength, and a fine silicone hollow fiber with a diameter of 30 microns and wall thickness of 50 microns, which is approximately half that of a conventional silicone hollow fiber. Using this newly developed silicone hollow fiber, the authors developed a compact extracapillary flow Membrane Oxygenator. The Oxygenator consists of fine silicone hollow fibers inserted in a housing made of polycarbonate. The housing is a cylindrical case, 20 cm long and 55 mm in inside diameter. The hollow fibers are cross-wound. The surface area of the Membrane is 2.0 m2, and priming volume is 230 ml. Gas transfer performance of the newly developed Oxygenator was evaluated by in vitro experiments. Oxygen and carbon dioxide transfer rates were 195 ml/min and 165 ml/min, at a blood flow rate 3 L/min. The novel silicone Membrane Oxygenator developed in this study can be used for extended duration in such applications as extracorporeal Membrane oxygenation.

Tomohiro Maeda - One of the best experts on this subject based on the ideXlab platform.

  • development of silicone rubber hollow fiber Membrane Oxygenator for ecmo
    Artificial Organs, 2003
    Co-Authors: Tadashi Motomura, Koshiro Sato, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Toshiyuki Shinohara, Yoichiro Kawaguchi
    Abstract:

    Silicone rubber hollow fiber Membrane produces an ideal gas exchange for long-term ECMO due to nonporous characteristics. The extracapillary type silicone rubber ECMO Oxygenator having an ultrathin hollow fiber Membrane was developed for pediatric application. The test modules were compared to conventional silicone coil-type ECMO modules. In vitro experiments demonstrated a higher O 2 and CO 2 transfer rate, lower blood flow resistance, and less hemolysis than the conventional silicone coil-type modules. This Oxygenator was combined with the Gyro C1E3 centrifugal pump, and three ex vivo experiments were conducted to simulate pediatric V-A ECMO condition. Four day and 6 day experiments were conducted in cases 1 and 2, respectively. Case 3 was a long-term experiment up to 2 weeks. No plasma leakage and stable gas performances were achieved. The plasma free hemoglobin was maintained within a normal range. This compact pump-Oxygenator system in conjunction with the Gyro C1E3 centrifugal pump has potential for a hybrid total ECMO system.

  • extracorporeal Membrane Oxygenator compatible with centrifugal blood pumps
    Artificial Organs, 2002
    Co-Authors: Tadashi Motomura, Shinji Kawahito, Tomohiro Maeda, Takahiro Matsui, Seiji Ichikawa, Hiroshi Ishitoya, Masaki Kawamura, Ikuya Nishimura, Toshiyuki Shinohara, Daniel Oestmann
    Abstract:

    : Coil-type silicone Membrane Oxygenators can only be used with roller blood pumps due to the resistance from the high blood flow. Therefore, during extracorporeal Membrane oxygenation (ECMO) treatment, the combination of a roller pump and an Oxygenator with a high blood flow resistance will induce severe hemolysis, which is a serious problem. A silicone rubber, hollow fiber Membrane Oxygenator that has a low blood flow resistance was developed and evaluated with centrifugal pumps. During in vitro tests, sufficient gas transfer was demonstrated with a blood flow less than 3 L/min. Blood flow resistance was 18 mm Hg at 1 L/min blood flow. This Oxygenator module was combined with the Gyro C1E3 (Kyocera, Japan), and veno-arterial ECMO was established on a Dexter strain calf. An ex vivo experiment was performed for 3 days with stable gas performance and low blood flow resistance. The combination of this Oxygenator and centrifugal pump may be advantageous to enhance biocompatibility and have less blood trauma characteristics.

  • preclinical evaluation of a new hollow fiber silicone Membrane Oxygenator for pediatric cardiopulmonary bypass ex vivo study
    Annals of Thoracic and Cardiovascular Surgery, 2002
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Tomohiro Maeda, Seiji Ichikawa, Masaki Kawamura, Kenji Nonaka, Joerg Linneweber, T Takano, Shuji Haraguchi, Hiroshi Ishitoya
    Abstract:

    Based on the results of many experimental models, a hollow fiber silicone Membrane Oxygenator applicable for long-term extracorporeal Membrane oxygenation (ECMO) was developed. For further high performance and antithrombogenicity, this preclinical model was modified, and a new improved Oxygenator was successfully developed. In addition to ECMO application, the superior biocompatibility of silicone must be advantageous for pediatric cardiopulmonary bypass (CPB). An ex vivo short-term durability test for pediatric CPB was performed using a healthy miniature calf for six hours. Venous blood was drained from the left jugular vein of a calf, passed through the Oxygenator and infused into the left carotid artery using a Gyro C1E3 centrifugal pump. For six hours, the O 2 and CO2 gas transfer rates were maintained around 90 and 80 ml/min at a blood flow rate of 2 L/min and V/ Q=3, respectively. The plasma free hemoglobin was maintained around 5 mg/dl. These data suggest that this newly improved Oxygenator has superior efficiency, less blood trauma, and may be suitable for not only long-term ECMO but also pediatric CPB usage. (Ann Thorac Cardiovasc Surg 2002; 8: 7‐11)

  • gas transfer performance of a hollow fiber silicone Membrane Oxygenator ex vivo study
    Artificial Organs, 2001
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Julie Glueck, Tomohiro Maeda, Seiji Ichikawa, Kenji Nonaka, Joerg Linneweber, T Takano, Minoru Mikami, Koshiro Sato
    Abstract:

    Based on the results of in vitro studies of many experimental models, a silicone hollow fiber Membrane Oxygenator for pediatric cardiopulmonary bypass (CPB) and extracorporeal Membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber with a 300 microm outer diameter and a wall thickness of 50 microm. In this study, we evaluated the gas transfer performance of this Oxygenator simulating pediatric CPB and ECMO conditions. Two ex vivo studies in a pediatric CPB condition for 6 h and 5 ex vivo studies in an ECMO condition for 1 week were performed with venoarterial bypass using healthy calves. At a blood flow rate of 2 L/min and V/Q = 4 (V = gas flow rate, Q = blood flow rate) (pediatric CPB condition), the O2 and CO2 gas transfer rates were maintained at 97.44 ± 8.88 (mean ± SD) and 43.59 ± 15.75 ml/min/m 2 , respectively. At a blood flow rate of 1 L/min and V/Q = 4 (ECMO condition), the O2 and CO2 gas transfer rates were maintained at 56.15 ± 8.49 and 42.47 ± 9.22 ml/min/m 2 , respectively. These data suggest that this preclinical silicone Membrane hollow fiber Oxygenator may be acceptable for both pediatric CPB and long-term ECMO use.

  • development of a new hollow fiber silicone Membrane Oxygenator in vitro study
    Artificial Organs, 2001
    Co-Authors: Shinji Kawahito, Tadashi Motomura, Tomohiro Maeda, Seiji Ichikawa, Masaki Kawamura, Kenji Nonaka, Joerg Linneweber, T Takano, Minoru Mikami, Julie Glueck
    Abstract:

    An experimental silicone hollow fiber Membrane Oxygenator for long-term extracorporeal Membrane oxygenation (ECMO) was developed in our laboratory using an ultrathin silicone hollow fiber. However, the marginal gas transfer performances and a high-pressure drop in some cases were demonstrated in the initial models. In order to improve performance the following features were incorporated in the most recent Oxygenator model: increasing the fiber length and total surface area, decreasing the packing density, and modifying the flow distributor. The aim of this study was to evaluate the gas transfer performances and biocompatibility of this newly improved model with in vitro experiments. According to the established method in our laboratory, in vitro studies were performed using fresh bovine blood. Gas transfer performance tests were performed at a blood flow rate of 0.5 to 6 L/min and a V/Q ratio (V = gas flow rate, Q = blood flow rate) of 2 and 3. Hemolysis tests were performed at a blood flow rate of 1 and 5 L/min. Blood pressure drop was also measured. At a blood flow rate of 1 L/min and V/Q = 3, the O2 and CO2 gas transfer rates were 72.45 ± 1.24 and 39.87 ± 2.92 ml/min, respectively. At a blood flow rate of 2 L/min and V/Q = 3, the O2 and CO2 gas transfer rates were 128.83 ± 1.09 and 47.49 ± 5.11 ml/min. Clearly, these data were superior to those obtained with previous models. As for the pressure drop and hemolytic performance, remarkable improvements were also demonstrated. These data indicate that this newly improved Oxygenator is superior to the previous model and may be clinically acceptable for long-term ECMO application.

Chiungjen Wu - One of the best experts on this subject based on the ideXlab platform.