Oxygenator Research Articles

Affinity Pixie Oxygenator and Cardiotomy/Venous Reservoir With Balance Biosurface

Affinity Pixie Oxygenator and Cardiotomy/Venous Reservoir With Balance Biosurface

To Purge or Not to Purge.

To remove gaseous microemboli (GME) using an oxygenator with an integrated arterial filter, it is recommended by some manufacturers to purge the oxygenator as an additional safety feature while on bypass. In this in vitro study, we evaluated whether purging of oxygenators with an integrated arterial filter is efficient in reducing GME. Five different types of commercially available contemporary oxygenators with an integrated arterial filter based on progressive filter filtration (1), cascade filtration (1), screen filtration (2), or self-venting (1) were tested for their efficiency in removing GME while keeping the purge line open or closed. A bubble counter was used for pre- and post-oxygenator GME signaling, from which the filter efficiency was computed. Freshly drawn heparinized porcine blood was used at blood flow rates of 3 and 5 L/min. Three units of each oxygenator were tested with its specific reservoir at a fixed volume level of 1,500 mL. GME load was introduced into the venous line at 1,000 mL air/min. Measurements started as soon as GME were detected by the pre-oxygenator probe and then continued for 1 minute. There was no statistically significant difference in filter efficiency between the purged and non-purged groups for specific oxygenators. At a blood flow of 3 L/min, the average filter efficiency stayed approximately invariable when comparing the non-purged and purged groups, where 89.1-88.2% indicated the largest difference between the groups. At a blood flow rate of 5 L/min, the filter efficiency changed in one screen filter group from an average of 55.7% in the non-purged group to 42.4% in the purged group. Other filter efficiencies at the blood flow rate of 5 L/min for non-purged compared with purged groups were, respectively, 98.0 vs. 98.0% (screen filtration), 88.6 vs. 85.8% (self-venting filtration), 82.8 vs. 75.5% (progressive filter filtration), and 65.4 vs. 65.1% (cascade filtration). Based on these results, purging while confronted with continuous GME challenge did not result in an increased filter efficiency.

Fully Resolved Computational (CFD) and Experimental Analysis of Pressure Drop and Blood Gas Transport in a Hollow Fibre Membrane Oxygenator Module

Membrane oxygenators or artificial lungs have become a reliable and live saving clinical technique. To limit side effects on blood platelet parameters the high extrinsic surface introduced by the hollow fiber membrane packing has to be decreased. This adjustment must be accompanied with an improvement of gas exchange performance to guarantee sufficient blood gas transfer. Computational fluid dynamics (CFD) provides a spatial and temporal resolution of the membrane oxygenation process and enables systematic optimization of artificial lungs. In scope of this research a new CFD approach to examine the gas exchange performance of oxygenators was developed. Blood and sweep gas flow in the fiber packing as well as blood gas exchange through the membrane between blood and sweep fluid are fully resolved and simulated. The results were compared to in vitro experiments comprising determination of blood side pressure loss and CO2 exchange performance of a prototype membrane module. While flow simulations were conducted for the complete prototype module, gas exchange simulations were limited to a representative fiber packing segment. The presented simulation approach provides a basis for the design of future artificial lungs.

Açık kalp cerrahisinde pompa sisteminden oksijenatörün çıkarılması: deneysel hayvan çalışması

Amaç: Koyun kullanılan bu deneysel çalışmada, pompa ile yapılan rutin açık kalp cerrahisi yönteminde, oksijenatör yerine pulmoner sistemin kullanılabileceği hipotezinin teknik olarak mümkün olup olmadığı araştırılmıştır.Gereç ve Yöntem: Beş adet dişi Ankara koyunu kullanılan çalışmada hayvanlara pompa ile açık kalp ameliyatı uygulanmıştır. Temel fark venöz kanülasyon sağ atriyum yerine sol atriyuma yapılmış, oksijenatör sistemden çıkarılmıştır. Kardiyak arrest için 2 denekte ventriküler fibrilasyon, 2 denekte kros klemp-potasyum kardiyoplejisi tekniği kullanılmıştır. 30 dakika boyunca sürüdülen kardiyak arrest boyunca debiler, tansiyonlar, arter kan gazı değerleri gibi hemodinamik parametreler kaydedilmiştir. İlk denek tekniğin gerekli şekilde uygulanması sonucu pompa aşamasında ölmüştür. Diğer hayvanların hayatı test sonuçları elde edildikten sonra sonlandırılmıştır. Sonuç: İn vivo olarak, tamamen hidrodinamik bir test şeklinde yürütülen çalışmada tekniğin en azından bu testte mümkün olabildiği görülmüştür. Hemodinaminin sıkı takibi ve santral venöz basıncın 18 mmHg civarında tutulmasıyla, ek bir pompaya gerek kalmadan sağ atriyum kanı spontan olarak sol atriyuma geçebilmiştir. Geçen kan miktarı 30dk boyunca, hedef kardiyak indeksin üzerinde stabil olarak sağlanabilmiştir. Çalışmanın düşündürdüğü bir başka sonuç da; akut miyokard infarktüsü gibi bir nedenle kalbin ventriküler fibrilasyona girdiği veya elektriksel iletinin bozularak kalbin kasılmadığı durumlarda sadece sol atriyum-aort arasına perkütan olarak yerleştirilecek bir pompa sistemiyle kardiyak ve sistemik dolaşımda perfüzyon sağlanabileceği şeklindedir.

Analysis of factors related to non-surgical hemorrhage and related progress of precise blood transfusion after cardiac valve replacement surgery

Cardiac valve replacement is the most common surgical procedure in cardiac surgery, which often results in non-surgical bleeding.There are many factors that cause non-surgical bleeding after cardiac surgery, which can be summed up as the disease itself, the artificial device of cardiopulmonary bypass and the special requirements during the operation, including the abnormality of liver function, extracorporeal circulation conduits, oxygenators and blood pumps, hypothermia, hemodilution, neutralization between protamine and heparin.At present, most hospitals still use the results of blood loss and coagulation test as the reference for blood transfusion. Only a few hospitals have used thromboelastogram to guide blood transfusion, which is still in the exploratory stage, so far there is no unified reference standard. This review will focus on the related factors leading to non-surgical bleeding and the concept of accurate blood transfusion and reducing blood transfusion after heart valve replacement in order to prevent the occurrence of rethoracotomy to hemostasis. Key words: Blood coagulation disorders; Cardiopulmonary bypass; Heart valve diseases

The experimental study of endothelial progenitor cells in rat liver decellularized scaffold

Objective To engineer intact whole rat liver decellularized scaffolds and repopulated bone marrow-derived endothelial progenitor cells (EPCs) into the scaffolds by continous perfusion technology thus providing experimental support for the vasculation of decellularized liver scaffolds in liver engineering. Methods Decellularized liver scaffolds were obtained by perfusing method. The composition and structure was examed by hematoxylin-eosin staining (HE) and immunohistochemistry. Bone marrow derived EPCs were characterised by immunofluorescence of CD31, CD133 and Vascular endothelial growth factor (VEGF). EPCs were recellularized into the decellularized scaffolds by portal-vein infusion method and cultured by the dynamic circulation perfusion device. After cultivation, HE staining and immunofluorescence of CD31 were conducted to observe the growth situation of EPCs in the scaffolds. Results The rat decellulariezd liver scaffolds were successfully obtained by perfusion method. Histological staining demonstrated the remove of cellular component and the reservation of extracellular cell matrix. Immunohistochemistry staining demonstrated the retention of collagen I and laminin. The primary cultured EPCs were postive for CD31, CD133 and VEGF. The circulation perfusion device was composed of a peristaltic pump, oxygenator, chamber and the convey tubes. HE staining and immunofluorence revealed that EPCs can be located around the blood vessel wall. Conclusion The primary cultured EPCs can grew around the blood vessel wall of the decellularized liver scaffolds by circulation perfusion method. Key words: Liver; Decellularized scaffolds; Circulation perfusion culture; Vascularization

In vitro and in vivo test of a customized system for extracorporeal life support

Objective We tried to develop a reliable, stable and effective customized ECLS system through a well designed in vitro and in vivo study. Methods An in vitro test model of the ECLS system, mainly consisting of a pseudo-patient (a blood reservoir), bladder, oxygenator, pump tube (outer diameter: 1/4 inch), roller pump and the heater, was built. Performances of the pump, monitors, and the heater were observed every day. The precision of the pump flow (pressure monitor or the heater) was compared with a transonic flow-meter (Medtronic ECMO system or thermometer). The monitors were tested to see if they could meet the requirements. Four healthy and two mild ARDS piglets were supported with the customized ECLS system for 24 hours. Hemodynamics, lung mechanics, gas change and hematological parameters of the piglets and performances of the machine were recorded. Agreement between the customized ECLS system and other devices including the transonic flow-meter, Medtronic ECMO system and thermometer was evaluated by the Bland-Altman method. Results The pump, the monitors, and the heater functioned well without accidently stopping working. The 95% limits of agreement of pump flow, pre-pump pressure, post-pump pressure, post-membrane pressure, and temperature were (-0.04 L/min, 0.03 L/min), (-3 mmHg, 3 mmHg), (-5 mmHg, 6 mmHg), (-6 mmHg, 6 mmHg), (0.1 ℃, 0.3 ℃). The pressure monitors and the bladder could alarm and stop the pump fast during a 100 times trail. The bubble detector could respond well (alarm and stop the pump) to 60 of the 100 bubbles injected into the circuit. The alarming temperature of the heater was (42.3±0.2)℃. The customized ECLS worked well without complications throughout the in vivo test. A temporary decrease of Cdyn and increase of A-aDO2 and OI were observed in healthy piglets while an escalating trend of Cdyn and a downtrend of A-aDO2 and OI in ARDS piglets. Mean arterial blood pressure of the piglets supported with the customized ECLS system maintained stable while the Hb and PLT decreased. Conclusion In vitro and in vivo test showed the pump, pressure monitors and the heater of the customized ECLS system functioned well, and the feasibility, safety and stability of the system were preliminarily verified from the cytosol of the cell to the lumen of the sarcoplasmic reticulum. Key words: Extracorporeal life support; Customized; In vitro; In vivo; Agreement

Cardiac stun in extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is a technology of cardiopulmonary life-support, where blood is drained from the venous vascular to an oxygenator, circulated outside the body by a mechanical pump, and then reinfused into the circulation.Recently, the application of ECMO in China is increasing gradually.Effective prevention and treatment of complications of ECMO is an important factor for the success of this technology.The aim of this paper is to discuss cardiac stun during ECMO support. Key words: Extracorporeal membrane oxygenation; Complication; Cardiac stun,

Respiratory support of extracorporeal membrane oxygenation in children

Patients with respiratory crisis occupied a large numbers in extracorporeal membrane oxygenation(ECMO) group.ECMO is able to give a plenty amount of gas exchange for body essential metabolic needs by ECMO oxygenator whoever the lungs are of function or not.The key indications for respiratory ECMO are that the patient had no response to all medical treatment except ECMO, and the origin cause of the disease is potentially recoverable.Besides the contraindications and accessibility, ECMO has no special settings among the different ages or cause of diseases.The VV-ECMO is preferred for respiratory support.VA-ECMO should be considered if cardiovascular failure exists.ECMO may offer a powerful respiratory support to patient with critically ill conditions until recovery.The outcomes are influenced by some factors including the reversibility and the cause of diseases. Key words: Extracorporeal membrane oxygenation; Respiratory support,

Successful Retrieval of a Fractured Guidewire during Extracorporeal Membrane Oxygenator Insertion

본 증례는 체외막산소공급기의 삽입 중 유도철선이 절단되었고 이를 경피적 풍선확장술로 절단된 유도철선을 카테터에 밀착하여 제거한 34세 여자 환자의 사례이다. 체외막산 소공급기를 삽입하는 과정에서 유도철선이 절단되는 경우에 대해서는 아직 보고된 바가 없어 카테터내 경피적 풍선확장술을 활용하여 성공적으로 제거한 1예를 보고하는 바이다.

A numerical performance assessment of a commercial cardiopulmonary by-pass blood heat exchanger

We developed a numerical model, based on multi-physics computational fluid dynamics (CFD) simulations, to assist the design process of a plastic hollow-fiber bundle blood heat exchanger (BHE) integrated within the INSPIRETM, a blood oxygenator (OXY) for cardiopulmonary by-pass procedures, recently released by Sorin Group Italia. In a comparative study, we analyzed five different geometrical design solutions of the BHE module. Quantitative geometrical-dependent parameters providing a comprehensive evaluation of both the hemo- and thermo-dynamics performance of the device were extracted to identify the best-performing prototypical solution. A convenient design configuration was identified, characterized by (i) a uniform blood flow pattern within the fiber bundle, preventing blood flow shunting and the onset of stagnation/recirculation areas and/or high velocity pathways, (ii) an enhanced blood heating efficiency, and (iii) a reduced blood pressure drop. The selected design configuration was then prototyped and tested to experimentally characterize the device performance. Experimental results confirmed numerical predictions, proving the effectiveness of CFD modeling as a reliable tool for in silico identification of suitable working conditions of blood handling medical devices. Notably, the numerical approach limited the need for extensive prototyping, thus reducing the corresponding machinery costs and time-to-market.

A fetal goat model of the veno-venous extracorporeal life support

Objective To establish a fetal goat model of the veno-venous artificial placenta support.Methods Five pregnant goats with 100 to 140 days gestation underwent cesarean deliver.Veno-venous artificial placentas were established to support fetal goats.The fetal blood drained from right jugular vein was pumped to an umbilical vein via artificial placenta.Fetuses were incubated in the warm saline at 40 ℃.The artificial placenta circuit consisted of a centrifugal pump,a neonatal membrane oxygenator,an uhrafilter,et al.Fetal echocardiography was performed to access fetal cardiac output of two ventricles before support and 3 hours and 6 hours during support.Fetal hemodynamics were monitored and blood gase were assayed during support.Results During support,fetal hemodynamics were stable.The level of Lac increased remarkably [(5.26 ± 1.57) mmol/L vs.(14.04 ± 2.74) mmol/L,P ＜ 0.01] with a slight increase of the potassium.Fetal cardiac output of left ventricle decreased without significant differences.Fetal cardiac output of right ventricle tended to decrease without significant difference at the 6th hour compared with that before support [(264.81 ± 163.57) ml/(kg· min) vs.(208.94 ± 125.99) ml/(kg* min)].Conclusion The veno-venous artificial placenta might be a practicable experimental model for supporting the premature fetuses.However,we were supposed to be careful with the tender and vulnerable tissues. Key words: Extracorporeal life support; Artificial placenta; Fetal goat; Cardiac output

Use of Spectrum Medical M3 monitor in pediatric cardiac surgery: gaseous emboli monitoring in Capiox RX05 and Capiox FX05 oxygenators

Amac: Spectrum Medical M3 monitorunun klinik kullanimiyla birlikte arteriyel filtresiz Terumo Capiox RX05 ve entegre arteriyel filtreli Capiox FX05 oksijenatorlerde emboli monitorizasyonunun sonuclari incelendi. Ca­lis­ma­ pla­ni:­ Spectrum Medical M3 monitoru Aralik 2010 ve Haziran 2011 tarihleri arasinda 50 hastada kullanildi. Otuz hastada (grup 1; 21 erkek, 9 kiz; ort yas 26.3±12.4 ay) Capiox RX05, 20 hastada (group 2; 10 erkek, 10 kiz; ort. yas 22.4±12 ay) Capiox FX05 oksijenatoru kullanildi. Ortalama yas grup 1’de 26.3±12.4 ay, grup 2’de 22.4±12 ay idi. Heparin dozu 400 unite/kg idi. Etkinlestirilmis pihtilasma zamani >500 saniyede, hematokrit %25-30 arasinda ve kardiyopulmoner baypas debisi 125-150/mL/kg/dakikada korundu. Orta dereceli hipotermi (28-34 derece), alfa stat kan gazi yonetimi ve antegrad izotermik kan kardiyoplejisi kullanildi. Bul gu lar: Grup 1’de mortalite gozlenmedi. Grup 2’de bir hasta pulmoner hipertansiyon nedeni ile oldu. Grup 1 ve grup 2’de iki hastada pnomoni nedeni ile uzun sureli solunum destegi gerekti. Grup 1’de arteriyel gaz embolisi sayisi ortalama 32573 (2306360051) (%25-75 persentil), ortalama gaz embolisi volumu 4.2 mL (2.1-7.5 mL) (%25-75 persentil) idi. Grup 2’de arteriyel gaz embolisi sayisi ortalama 25053 (9096.3-37352.3) (%25-75 persentil), ortalama gaz embolisi volumu 1.1 mL (0.5-3.2 mL) (%25-75 persentil) (Arteriyel emboli sayisi icin p degeri 0.043, arteriyel emboli volumu icin p degeri 0.001) idi. So­nuc:­ Spectrum Medical M3 monitoru pediyatrik kalp cerrahisinde gaz embolisi monitorizasyonu icin faydali bir cihazdir. Gaz embolisinden korunmada entegre arteriyel filtreli Terumo FX05 oksijenator, arteriyel filtresi olmayan Capiox RX05 oksijenatorden daha etkili olabilir. Anah tar soz cuk ler: Kardiyopulmoner baypas; gaz embolisi; pediyatrik kalp cerrahisi. Background:­The clinical use of Spectrum Medical M3 monitor, and the results of emboli monitoring for Terumo Capiox RX05 oxygenator without arterial filter and Terumo Capiox FX05 oxygenator with built in arterial filter were evaluated. Methods: Spectrum Medical M3 monitor was used for 50 patients between December 2010 and June 2011. Capiox RX05 oxygenator was used for 30 patients (group 1; 21 boys, 9 girls; mean age 26.3±12.4 months), and Capiox FX05 oxygenator was used for 20 patients (group 2; 10 boys, 10 girls; mean age 22.4±12 months). Heparin dose was 400 units/kg. Activated clotting time was maintained at >500 seconds, hematocrit was maintained at 25-30%, and cardiopulmonary bypass flow was maintained at 125-150 mL/kg/minute. Moderate hypothermia (2834 degrees), alfa stat blood gas management, and antegrade isothermic blood cardioplegia were used. Results:­No mortality was observed in group 1. In group 2, one patient died due to pulmonary hypertension. Two patients needed prolonged respiratory support for pneumonia in group 1 and group 2. In group 1, the mean number of arterial gaseous emboli was 32573 (23063-60051) (25-75% percentile), and mean volume of arterial gaseous emboli was 4.2 mL (2.1-7.5 mL) (25-75% percentile). In group 2, the mean number of arterial gaseous emboli was 25053 (9096.3-37352.3) (25-75% percentile), and mean volume of arterial gaseous emboli was 1.1 mL (0.5-3.2 mL) (25-75% percentile) (p value for the number of arterial emboli was 0.043, and p value for arterial emboli volume was 0.001). Conclusion:­Spectrum Medical M3 monitor is a useful device for monitoring gaseous emboli in pediatric cardiac surgery. Terumo Capiox FX05 oxygenator with built in arterial filter may be more effective for the prevention of gaseous emboli than Terumo Capiox RX05 oxygenator without arterial filter.

A novel, minimally invasive rat model of normothermic cardiopulmonary bypass model without blood priming.

Cardiopulmonary bypass (CPB) has been shown to be associated with systemic inflammatory response leading to postoperative organ dysfunction. Elucidating the underlying mechanisms and developing protective strategies for the pathophysiological consequences of CPB have been hampered due to the absence of a satisfactory recovery animal model. The purpose of this study was to establish a novel, minimally invasive rat model of normothermic CPB model without blood priming. Twenty adult male Sprague-Dawley rats weighing 450-560 g were randomly divided into CPB group (n = 10) and control group (n = 10). All rats were anaesthetized and mechanically ventilated. The carotid artery and jugular vein were cannulated. The blood was drained from the right atrium via the right jugular and further transferred by a miniaturized roller pump to a hollow fiber oxygenator and back to the rat via the left carotid artery. The volume of the priming solution, composed of 6% HES 130/0.4 and 125 IU heparin, was less than 12 ml. The surface of the hollow fiber oxygenator was 0.075 m(2). CPB was conducted for 60 minutes at a flow rat of 100-120 ml × kg (-1)× min(-1) in CPB group. Oxygen flow/perfusion flow was 0.8 to 1.0, and the mean arterial pressure remained 60-80 mmHg. All CPB processes were successfully achieved. Blood gas analysis and hemodynamic parameters of each time point were in accordance with normal ranges. The vital signs of all rats were stable. The establishment of CPB without blood priming in rats can be achieved successfully. The nontransthoracic model should facilitate the investigation of pathophysiological processes concerning CPB-related multiple organ dysfunction and possible protective interventions. This novel, recovery, and reproducible minimally invasive CPB model may open the field for various studies on the pathophysiological process of CPB and systemic ischemia-reperfusion injury in vivo.

Effects of sevoflurane postconditioning on lung function after cardiopulmonary bypass in patients undergoing cardiac valve replacement

Objective To evaluate the effects of sevoflurane postconditioning on lung function after cardiopulmonary bypass (CPB) in patients undergoing cardiac valve replacement.Methods Thirty ASA physical status Ⅱ or Ⅲ patients,aged 33-64 yr,weighing 47-81kg,scheduled for cardiac valve replacement with CPB,were equally and randomly divided into control group (group C) or sevoflurane postconditioning group (group S).Anesthesia was induced with iv injection of midazolam,etomidate,fentanyl and rocuronium.The patients were endotracheally intubated and mechanically ventilated.Anesthesia was maintained with intermittent iv boluses of midazolam,fentanyl and pipecuronium.In group S,2％ sevoflurane was washed into the membrane oxygenator at 2 min before aortic unclamping and continuously washed into the membrane oxygenator for 15 min after aortic unclamping.Before anesthesia (T1),immediately after sternum splitting (T2),at 30 min after termination of CPB (T3),and at 6,12 and 24h after operation (T4-6),blood samples were taken from the radial artery for blood gas analysis and PaO2 and SaO2 were recorded.Oxygen index (OI),alveolar-arterial oxygen tension difference (DA-aO2),dynamic pulmonary compliance (Cdyn) and static pulmonary compliance (Cstat) were calculated.Arterial blood samples were collected at T1,T3,T4 and T6 for determination of serum concentrations of IL-17A,neutrophil elastase (NE) and matrix metalloproteinase-9 (MMP-9).The time of mechanical ventilation after surgery and development of dyspnea,re-intubation and pulmonary rales were recorded.Results Compared with group C,OI at T4T6,PaO2 at T4 and T5,SaO2 at T3 and T6,Cdyn at T3 and T4 and Cstat at T4 were significantly increased,DAaO2 at T5 and T6,serum concentrations of IL-17A,NE and MMP-9 at T3,T4 and T6,and the incidence of pulmonary rales were decreased,and the time of mechanical ventilation was shortened (P ＜ 0.05),and no significant change was found in the incidence of dyspnea in group S (P ＞ 0.05).No re-intubation was required in the two groups.Conclusion Sevoflurane postconditioning can improve the lung function after CPB in patients undergoing cardiac valve replacement and inhibition of inflammatory responses may be involved in the mechanism. Key words: Anesthetics, inhalation; Respiratory function tests; Cardiopulmonary bypass; Heart valve prosthesis implantation

Management of cardiopulmonary bypass for infants below 10 kilograms with congenital heart diseases

Objective To summarize the management of cardiopulmonary bypass （CPB） for infants below 10 kilograms with congenital heart diseases. Methods From Jan 2010 to Apr 2011 ,the clinical datas of 122 infants aged from 1.5 months to 2 years with body weight 3 to 10 kilograms,who underwent open heart surgery under mild or moderate hypothermia CPB were retrospectively analyzed. Results Among all the 122 infants, CPB time was 13 - 118 min [ （62. 69± 21.48 ） min], aortic cross-clamp time was 0 to 86 min [ （ 35.47 ± 19.51 ） min]. All patients were spontaneous resuscitation and successfully weared from the machine, no severe complications associated with CPB occurred, 3 infants died （ 2. 46 %, 3/122 ） after operation. Conclusion Using membrane oxygenator, circuit tubing and artery filter with less priming, and highflow perfusion during CPB, maintaining hemodynamics stable, holding reasonable hematocrit and colloid osmotic pressure, good myocardial protection and ultrafiltration are the significant elements of the management of CPB in infants with weight less than 10 kilograms. Key words: Congenital heart diseases; Cardiopulmonary bypass; Body weight; Infants

Peritoneal ventilation for oxygenation of asphyxia rabbits

Objective To observe the oxygenation and heartbeat duration effect of peritoneal ventilation with oxygen on a rabbit asphyxia model so as to provide a basis for treatment of severe respiratory damage with peritoneal oxygenation technique. Methods Twenty-four New Zealand rabbits were randomized into control group,air group and oxygen group,eight rabbits per group.Trachea dissection and intubation,carotid artery and vein catheter and placement of peritoneal cavity in and out of air duct were performed.An asphyxia model was built by clamping the tracheal catheter and was administered with peritoneal ventilation (with air in air group and oxygen in oxygen group).Indices including blood gas and mean arterial pressure (MAP) before and at an interval of one minute after asphyxia and heartbeat duration were observed,and their differences between groups were compared. Results The arterial partial pressure of oxygen ( PaO2 ) in the oxygen group was higher than that in the control group within four minutes after asphyxia.The partial pressure of carbon dioxide ( PaCO2 ) [ (77.6 ± 11.2) mm Hg] in the oxygen group was significantly lower than (89.1 ± 10.1 )mm Hg in the control group at four minutes after asphyxia.The heartbeat duration [ (6.48 ± 0.89 ) minutes ] in the oxygen group was longer than (5.03 ± 0.51 ) minutes in the control group.MAP had no obvious changes in the three groups. Conclusion The transperitoneal ventilation with gaseous oxygen can alleviate the decrease of PaO2,increase of PaCO2 and prolong the duration of heartbeat in an asphyxia rabbit model. Key words: Asphyxia; Oxygenators, membrane; Peritoneum; Duration of heartbeat

The Duplex Oxygenator of Elvard Moses

The Duplex Oxygenator of Elvard Moses

The comparative study of membrane oxygenator DDMO-100S and membrane oxygenator terumo SX-10 used in cardiopulmonary bypass in children

Objective To compare the gas and heat exchange performance of membrane oxygenator DDMO-100S and membrane oxygenator Terumo SX-10 in cardiopulmonary bypass(CPB)in children.Methods 39 children aged 3-12 yrs who suffered from congenital heart disease were selected,and the repair of ventricle septal defect or/and atrial septal defect was performed under cardiopulmonary bypass.The 39 children were randomly divided into Group DD(n =21)and Group SX(n = 18).Membrane oxygenator DDMO-100S(Made by Xi'an Daidai,China)was used in Group DD and Membrane oxygenator Terumo SX-10(Made by Terumo,Japan)in Group SX,respectively.The hypothermic cardiopulmonary bypass with high perfusion flow and the cool crystalloid cardioplegia were applied in all children.The artery blood samples were taken for measuring PO2 and PCO2 and the oxygenating index(OI)was calculated by the formulae(OI = PaO2/FiO2).The temperature at nasal pharynx was monitored and the rewarming time was recorded.Results The total priming volume in Group DD was bigger than in Group SX [(742.5 ± 107.3)ml vs(531.3 ± 84.3)ml,P ＜ 0.05].The PO2,OI and PCO2 at 15 min after CPB or at 5 min before cease of CPB had no differences in both group(P ＞0.05).The rewarming time had no difference in both group [(31.5 ± 10.2)min vs(30.61 ± 8.2)min,P ＞0.05].Conclusions Under our observation condition,the gas and heat exchange performance of membrane oxygenator DDMO-100S were the same as membrane oxygenator Terumo SX-10,when it was used in cardiopulmonary bypass in children,but it had a little bit more priming volume. Key words: Extracorporeal membrane oxygenation/MT; Extracorporeal circulation; Rewarming

Evaluation of the oxygen transfer rate of oxygenator based on intermittent non-steady state method

Evaluation of the oxygen transfer rate of oxygenator based on intermittent non-steady state method