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Heart-lung Machine (heart-lung + machine)
Selected AbstractsThe Aachen MiniHLM,A Miniaturized Heart-Lung Machine for Neonates With an Integrated Rotary Blood PumpARTIFICIAL ORGANS, Issue 9 2010Jutta Arens Abstract The operation of congenital heart defects in neonates often requires the use of heart-lung machines (HLMs) to provide perfusion and oxygenation. This is prevalently followed by serious complications inter alia caused by hemodilution and extrinsic blood contact surfaces. Thus, one goal of developing a HLM for neonates is the reduction of priming volume and contact surface. The currently available systems offer reasonable priming volumes for oxygenators, reservoirs, etc. However, the necessary tubing system contains the highest volumes within the whole system. This is due to the use of roller pumps; hence, the resulting placement of the complete HLM is between 1 and 2 m away from the operating table due to connective tubing between the components. Therefore, we pursued a novel approach for a miniaturized HLM (MiniHLM) by integrating all major system components in one single device. In particular, the MiniHLM is a HLM with the rotary blood pump centrically integrated into the oxygenator and a heat exchanger integrated into the cardiotomy reservoir which is directly connected to the pump inlet. Thus, tubing is only necessary between the patient and MiniHLM. A total priming volume of 102 mL (including arterial filter and a/v line) could be achieved. To validate the overall concept and the specific design we conducted several in vitro and in vivo test series. All tests confirm the novel concept of the MiniHLM. Its low priming volume and blood contact surface may significantly reduce known complications related to cardiopulmonary bypass in neonates (e.g., inflammatory reaction and capillary leak syndrome). [source] The Early History of Cardiac Surgery in StockholmJOURNAL OF CARDIAC SURGERY, Issue 6 2003Kjell Radegran M.D. The portal figure is Clarence Crafoord (1899,1983) who already in 1927 had succeeded with the Trendelenburg pulmonary embolectomy operation. He went on to develop lung surgery in general. With foresight he stimulated the chemists of Karolinska Institute to purify heparin, first for prophylaxis against venous thromboembolism and later for use with the heart-lung machine. In 1944 he became the first surgeon to successfully operate on patients with coarctation of the aorta. With Viking Olov Bjork and Ake Senning the heart-lung machine was improved, finally allowing its clinical use in a patient operated in 1954 for a myxoma of the left atrium, with long-term survival. This was the first successful use of the heart-lung machine in Sweden and the second in the world. He and his coworkers, first at the Sabbatsberg hospital and from 1957 at the Karolinska hospital made major contributions to cardiology and radiology, apart from the progresses in cardiac surgery. Contributions such as pressure recording from the left atrium by needle puncture in 1950, the Senning operation for transposition of the great arteries and the first use of a totally implantable cardiac pacemaker in 1958 are indeed medical history. (J Card Surg 2003;18:564-572) [source] The Aachen Miniaturized Heart-Lung Machine,First Results in a Small Animal ModelARTIFICIAL ORGANS, Issue 11 2009Heike Schnoering Abstract Congenital heart surgery most often incorporates extracorporeal circulation. Due to foreign surface contact and the administration of foreign blood in many children, inflammatory response and hemolysis are important matters of debate. This is particularly an issue in premature and low birth-weight newborns. Taking these considerations into account, the Aachen miniaturized heart-lung machine (MiniHLM) with a total static priming volume of 102 mL (including tubing) was developed and tested in a small animal model. Fourteen female Chinchilla Bastard rabbits were operated on using two different kinds of circuits. In eight animals, a conventional HLM with Dideco Kids oxygenator and Stöckert roller pump (Sorin group, Milan, Italy) was used, and the Aachen MiniHLM was employed in six animals. Outcome parameters were hemolysis and blood gas analysis including lactate. The rabbits were anesthetized, and a standard median sternotomy was performed. The ascending aorta and the right atrium were cannulated. After initiating cardiopulmonary bypass, the aorta was cross-clamped, and cardiac arrest was induced by blood cardioplegia. Blood samples for hemolysis and blood gas analysis were drawn before, during, and after cardiopulmonary bypass. After 1 h aortic clamp time, all animals were weaned from cardiopulmonary bypass. Blood gas analysis revealed adequate oxygenation and perfusion during cardiopulmonary bypass, irrespective of the employed perfusion system. The use of the Aachen MiniHLM resulted in a statistically significant reduced decrease in fibrinogen during cardiopulmonary bypass. A trend revealing a reduced increase in free hemoglobin during bypass in the MiniHLM group could also be observed. This newly developed Aachen MiniHLM with low priming volume, reduced hemolysis, and excellent gas transfer (O2 and CO2) may reduce circuit-induced complications during heart surgery in neonates. [source] Comparison of Pumps and Oxygenators With Pulsatile and Nonpulsatile Modes in an Infant Cardiopulmonary Bypass ModelARTIFICIAL ORGANS, Issue 11 2009Nikkole M. Haines Abstract As the evidence mounts in favor of pulsatile perfusion during CPB, it is necessary to investigate the effect of circuit components on the quality of pulsatility delivered throughout the circuit. We compared two bloodpumps, the Jostra HL-20 heart-lung machine and the MEDOS DELTASTREAM DP1 Bloodpump, and two oxygenators, the Capiox Baby RX05 and the MEDOS HILITE 800LT, in terms of mean arterial pressure, energy equivalent pressure, surplus hemodynamic energy, total hemodynamic energy, and pressure drop over the oxygenators using a blood analog. The pumps and oxygenators were combined in unique circuits and tested in nonpulsatile and pulsatile modes, at two flow rates (500 and 800 mL/min), and three rotational speed differentials when using the MEDOS DELTASTREAM DP1 Bloodpump for 144 trials in total. The Jostra Roller pump produced some pulsatility in nonpulsatile mode and better pulsatility in pulsatile mode than the MEDOS DP1 Bloodpump at a rotational speed differential of 2500 rpm, but not at 3500 or 4500 rpm. The MEDOS DP1 Bloodpump produced almost no pulsatility in nonpulsatile mode. Pressure drops over the Capiox Baby RX05 were markedly higher, at 92.5 ± 0.4 mm Hg with the MEDOS DP1 Bloodpump at 800 mL/min and 4500 rpm in pulsatile mode, than those of the MEDOS HILITE 800LT oxygenator, which was 67.0 ± 0.1 mm Hg at the same settings. These results suggest that careful selection of each circuit component, based on the individual clinical case and component specifics, are necessary to achieve the best quality of pulsatility. [source] | ||||||||||