bluuebunny/crossref_metadata_2025_split huggingface dataset:
The hazardous effects of alveolar hypocapnia on lung mechanics during weaning from cardiopulmonary bypass
Authors: Bayindir Osman , Akpinar Belhhan , Özbek Ug'ur , Cakali Emine , Pekcan Ülkü , Bulutçu Füsun , Sönmez Bingür 
Published: January 2013

The bronchoconstrictive effects of alveolar hypocapnia during weaning from cardiopulmonary bypass (CPB) were investigated in patients undergoing elective coronary artery revascularization. Thirty patients were randomly assigned into two equal groups. In both groups, mechanical ventilation was initiated for 3 min prior to weaning from CPB with the venous pressure low. This kept the pulmonary vascular bed empty, resulting in alveolar hypocapnia (ETCO2 < 2 kPa). Peak airway pressure ( Ppeak) and plateau pressures ( Pplateau) were recorded. In group 1, 5% CO2 was added to the inspiratory gas mixture and the ETCO2 allowed to rise (ETCO2 > 3.3 kPa). The ventilation pressure measurements were recorded again after 3 min stabilization. In group 2, the venous pressure was increased to allow the pulmonary venous bed to fill and the ventilation pressures recorded after a 3 min period of stabilization. In group 1, the ventilatory pressures dropped significantly ( p < 0.001) when the alveolar hypocapnia was reversed with added CO2 ( Ppeak 19.71 ± 5.7 to 12.31 ± 2.8 cmH2O and Pplateau 13.15 ± 3.28 to 9.15 ± 2.23 cmH2O). In group 2, a similar effect was achieved by allowing filling of the pulmonary vascular bed ( Ppeak 17.46 ± 4.72 to 11.92 ± 3.03 cmH2O and Pplateau 13.93 ± 4.10 to 9.37 ± 3.00 cmH2O). These results suggest that filling the pulmonary vascular bed prior to initiating ventilation, when weaning from CPB, prevents the otherwise deleterious effects of alveolar hypocapnia, resulting in raised bronchomotor tonus and raised airway pressures.
Affinity pump system: a new peristaltic blood pump for cardiopulmonary bypass
Authors: Jaggy C , Lachat M , Leskosek B , Zünd G , Turina M 
Published: January 2013

An in vitro study has been carried out to assess the pump performance of a new peristaltic, extracorporeal displacement pump (Affinity) for cardiopulmonary bypass. The pump system consists of a pump rotor (0-110 rpm), a pump chamber, a venous reservoir with a 5/8″ connecting tube and the Affinity console. The polyurethane chamber is connected to the venous reservoir by a 5/8″ tube and fills passively due to the hydrostatic pressure exhibited by the fluid height in the venous reservoir. The implementation of an occlusive segment in the pump chamber, which collapses in low filling states, should prevent significant negative pressures. An in vitro circuit was filled with bovine blood (37°C, hematocrit 35%) and the pump flow was measured by an ultrasonic transit time flow probe with respect to pre-load, diameter and length of attached tubing in the venous line, pump speed (rpm) and size of the connecting tube (3/8″ and 5/8″). At 108 rpm and a preload equal to 10 mmHg, the flow was 8.6 ± 0.42 l/min for an afterload of 80 mmHg. The reduction of the inlet connector to 3/8″ diminished the pump flow significantly to 5.2 ± 0.31 l/min ( p < 0.0001). The pump flow decreased linearly with respect to the length of the attached tube in the venous line and for a 2 m long 5/8″ silicon tube, the rpm-optimized flow was still 6.0 ± 0.28 l/min at a preload of 10 mmHg. In case of low filling state or too high rpm, the occlusive segment collapsed and no cavitation bubbles could be detected. Our in vitro measurements yield a nomogram for rpm-optimized blood flow with respect to the pre-load in the venous reservoir. The delivered 5/8″ connecting tube facilitates optimum filling of the pump chamber for high blood flow, but limits the use of venous reservoirs to Affinity products. The pump yields a high blood flow even when long tubing in the venous line is used. This makes the pump a candidate for a ventricular assist device. In hypovolemia or high rpm, the occlusive segment collapses and no negative pressure is generated at the inflow site of the pump chamber.
Comparison of two doses of aprotinin in patients receiving aspirin before coronary bypass surgery
Authors: Moran Sergio V , Lema Guillermo , Medel Jessica , Irarrazaval Manuel J , Zalaquett Ricardo , Garayar Bernardita , Flaskamp Renate 
Published: January 2013

This study was designed to evaluate efficacy and tolerability of two different doses of aprotinin in patients receiving aspirin before undergoing coronary artery bypass grafting. Forty-two patients were randomized to receive either placebo (group I), or aprotinin in doses of 4 000 000 KIU (group II) or 6 000 000 KIU (group III). Drug efficacy was determined by measuring postoperative blood loss and transfusion of blood products. Both doses were effective in reducing blood loss and transfusion requirements. Blood loss through thoracotomy drainage was 450 ± 224, 182 ± 144, 142 ± 98 ml, respectively, for control and treatment groups II and III ( p = 0.0001). The numbers of patients with blood transfusions were seven (50%), two (17%) and two (17%) for group I and treatment groups II and III, respectively ( p = 0.10). Tolerability was excellent and complications few and reversible. In conclusion, high and medium doses of aprotinin were well tolerated and reduced bleeding and transfusion requirements in patients submitted to coronary bypass surgery under the effects of aspirin.
Impact of membrane oxygenators on pulsatile versus nonpulsatile perfusion in a neonatal model
Authors: Ündar Akif , Koenig Karl M , Frazier O H , Fraser Charles D 
Published: January 2013

We investigated the effects of two new hollow-fiber membrane oxygenators, the Capiox SX10 and the Lilliput 901, on pulsatile versus nonpulsatile perfusion in an in vitro model designed to simulate a 3 kg infant. The experiments were divided into eight groups (six pulsatile and two nonpulsatile), according to the equipment and settings used. Each group included six tests. In all experiments, the pseudo-patient’s mean arterial pressure was 40 mmHg, and the pump flow rate was 550 ml/min. During pulsatile cardiopulmonary bypass, the pump’s base flow was set at 30%, and the pump rate was set at 80, 100, 120, 140, or 150 beats/min. The PUMP START and PUMP STOP timing points were adjusted to produce different pulse-width settings. We were especially interested in evaluating the pre- and postoxygenator extracorporeal circuit pressure (ECP), the oxygenator pressure drop, and the precannula ECP. When used with a pulsatile roller pump, the Capiox produced a significantly lower preoxygenator ECP than the Lilliput ( p < 0.001); moreover, the Capiox yielded a significantly lower oxygenator pressure drop ( p < 0.001). During nonpulsatile perfusion, the Capiox again produced a lower preoxygenator ECP than the Lilliput ( p < 0.001). These results suggest that the Capiox may be more suitable than the Lilliput when the pulsatile flow is employed, and pulsatile flow does not increase the ECP with either oxygenator.
Reoperation for a type I aortic dissection: case report
Authors: Wise Robert K , Wiggs Ned T , Dasilva Marcelo C , McCoach Robert M , Pae Walter E , Baer Larry D , Hamilton Lindy J , Hummer Gregory J , Kapp Christopher J , Williams Dennis R 
Published: January 2013

Surgery for the repair of a type I aortic dissection presents several difficulties for the surgeon and the perfusionist. One must safely support the patient, while at the same time provide the surgeon with a bloodless field in which to operate. Often, this requires cessation of the circulation for varying amounts of time. Deep hypothermia allows for an extension of the arrest period, while other techniques - retrograde cerebral perfusion and antegrade cerebral perfusion - provide an additional degree of cerebral protection. Recently, we utilized these techniques concurrently on a 43-year-old female who presented for a reoperation for a type I aortic dissection. Combining these techniques allowed us to adequately support the patient during an anticipated lengthy period of circulatory arrest and insured a successful operation without any adverse cerebral or other organ dysfunction.
Whole blood heparin concentrations do not correlate with plasma antifactor Xa heparin concentrations in pediatric patients undergoing cardiopulmonary bypass
Authors: Gruenwald C , de Souza V , Chan A KC , Andrew M 
Published: January 2013

This study was designed to test the validity of whole blood heparin concentration (WHBC) measurements using an on-site protamine titration assay with the Hepcon instrument (Medtronic Blood Management, Parker, CO, USA) in pediatric patients less than 1 year old undergoing cardiopulmonary bypass (CPB). The validity of the Hepcon measurements was examined via a test of correlation with the gold standard plasma antifactor Xa activity (anti-Xa) assay. Fifty-one patients (23 females and 28 males) under 1 year old (mean age 5.3 months) were studied prospectively. Blood samples were taken at 5 min into CPB and at the end of CPB for the WBHC, plasma anti-Xa activity, and hematocrit (Hct). The WBHC was converted to plasma heparin level using a formula taking into account the collection of blood into citrate solution and the effect of the citrate on the hematocrit. While a nonparametric statistical analysis revealed that the mean corrected values from the Hepcon instrument were not significantly different from the mean anti-Xa values ( p = 0.070 at 5 min on CPB, p = 0.518 at the end of CPB), there was no significant correlation between these values at either 5 min into CPB ( r = 0.113, p = 0.429) or at the end of CPB ( r = -0.247, p = 0.080). The lack of correlation between the two assays may be related to the extreme hemodilution observed during CPB in small children, which leads to very low concentrations of coagulation proteins. Due to this discrepancy, whole blood heparin monitors should be further evaluated in children undergoing CPB.
Pumpless arteriovenous extracorporeal lung assist: what is its role?
Authors: Grubitzsch Herko , Beholz Sven , Wollert Hans-Georg , Eckel Lothar 
Published: January 2013

Extracorporeal lung assist (ECLA) is an established treatment of severe pulmonary failure. Since extracorporeal perfusion is applied in a long-term fashion in this setting, the negative impact on blood compounds is of tremendous importance. Pumpless arteriovenous ECLA (av-ECLA) is an alternatively introduced technique that focuses on reduced blood traumatization. However, due to determining technical and physiological aspects, its clinical application is limited to a highly selected group of patients. Membrane oxygenators with minimal pressure gradients, as well as stable patients’ haemodynamics providing a sufficient cardiac output, are the most important prerequisites. With respect to recent reports, characteristic features of av-ECLA, with special emphasis on its physiological background, are reviewed. Accordingly, reasonable indications for its beneficial use are discussed. It is concluded that av-ECLA is a feasible technique when its limitations are accepted. For adequate clinical use, more data concerning indications, as well as time- and technique-related directions are required.
Coronary artery bypass grafting using a miniature right ventricular support system
Authors: Toomasian John M , Aboul-Hosn Walid 
Published: January 2013

Cardiopulmonary bypass (CPB) with cardioplegic myocardial preservation has long been the gold standard for surgical care of coronary artery disease. More recently, alternatives to the conventional approach of CPB-myocardial revascularization have been developed. Epicardial stabilizing devices have been used to immobilize areas of the beating heart to provide a stable surface for some coronary anastomoses. These approaches are often limited to anterior aspects of the heart because revascularization of posterior and lateral vessels often requires the heart to be manipulated or contorted. Excessive manipulation can lead to hemodynamic compromise as a result of partially obstructing pulmonary blood flow. A miniature extracorporeal system has been developed that uses right ventricular support and allows for epicardial surgical procedures to be conducted on a beating heart without standard CPB. The extracorporeal system consists of a coaxial atrial cannula that is connected to a miniature centrifugal pump. Blood is drained from the right atrium, passes through the miniature centrifugal pump and is delivered through the cannula’s inner reinfusion lumen into the pulmonary artery. The entire circuit volume is approximately 30 ml. The system is positioned on the sterile operative field. The pump is controlled by a console positioned adjacent to the patient. The centrifugal pump is capable of delivering blood flow at rates of 1-6 l/min. This extracorporeal system may be of benefit in maintaining adequate cardiac output during epicardial beating heart surgery.
Use of danaparoid sodium (Orgaran®) as an alternative to heparin sodium during cardiopulmonary bypass: a clinical evaluation of six cases
Authors: Fernandes Philip , Mayer Richard , MacDonald James L , Cleland Andrew G , Hay-McKay Christine 
Published: January 2013

Heparin-induced thrombocytopenia (HIT) has become more prevalent in today’s cardiac setting and has resulted in the need for alternative anticoagulant therapies. Danaparoid sodium, one alternative to heparin, has been used in six cardiopulmonary bypass procedures in this hospital. This clinical experience has resulted in the progressive refinement of a protocol for the ‘safe’ clinical use of danaparoid sodium. Although there were six positive outcomes with the use of danaparoid sodium, alternatives must be explored in order to find the optimal anticoagulant for the treatment of HIT.
Modified ultrafiltration removes serum interleukin-8 in adult cardiac surgery
Authors: Onoe Masahiko , Magara Tatsuo , Yamamoto Yoshio , Nojima Takehisa 
Published: January 2013

Cardiopulmonary bypass (CPB) causes an increase in serum cytokine levels and systemic inflamatory responses, which may trigger the onset of various types of postoperative organ failure. In the present study, modified ultrafiltration (MUF) was applied in cases of adult cardiac surgery and an attempt was made to determine whether MUF reduces serum interleukin-8 (IL-8) levels. Nine patients who underwent cardiovascular surgery with CPB and MUF between June 1996 and June 1997 were compared with nine control patients who underwent cardiovascular surgery without MUF in the same period. Modified ultrafiltration was performed, based on a method proposed elsewhere. Serum IL-8 was measured by enzyme immunoassay at the start of CPB, immediately after CPB, immediately after MUF and 3 h after MUF. The mean filtrated volume was 1550.0 ± 173.2 ml. In the MUF group, haematocrit increased significantly from 21.2 ± 2.0 to 24.9 ± 3.3% (p = 0.0008), while systolic blood pressure increased from 97.5 ± 16.7 to 116.5 ± 23.9 mmHg (p = 0.0024) after MUF. In contrast, there were no changes in either haematocrit or blood pressure in the control group. In the MUF group, serum IL-8 was reduced from 69.5 ± 33.5 to 58.9 ± 32.4 pg/ml after MUF (p = 0.0029), whereas it was not reduced in the control group. The results of the present study suggest that MUF has beneficial effects on postoperative haemodynamics, and can reduce serum IL-8 levels in adult cardiac surgery.
The side-effects of cardiopulmonary bypass on the lungs: changes in bronchoalveolar lavage fluids
Authors: Alat İlker , Yüksel Münevver , Büket Suat , Nalbantgil Sanem , Aşkar Fatma , Bayındır Ülkü , Taşbakan Sezai , Kokuludag Ali , Veral Ali 
Published: January 2013

Although technical refinements have improved the safety of cardiac operations, postoperative dysfunction of lung and other organs occurs frequently after cardiopulmonary bypass (CPB). The aim of the present study was to search the aetiopathogenesis of pulmonary complications due to CBP. Ten patients with stable coronary artery disease, undergoing coronary artery bypass grafting (CABG) surgery, were included in the study. Forty bronchoalveolar lavage (BAL) fluid samplings were performed in the 10 patients. Samples were obtained at the following time periods: (1) preoperatively; (2) at the end of the first hour after anaesthetic induction; (3) at the conclusion of 30 min of crossclamp on CPB; and (4) at the conclusion of 20 h after the end of CPB, postoperatively. Cell contents of bronchoalveolar lavage fluid, alveolar macrophage viability, eosinophil cationic protein (ECP) levels and myeloperoxidase (MPO) concentrations were analysed in each bronchoalveolar lavage fluids. While the percentage of preoperative macrophages was 85.90% and the percentage of preoperative neutrophils was 2.40%, they were 77.00% and 11.30% in the postoperative samples, respectively. Mean alveolar macrophage viability was 96.20% preoperatively and 90.40% in the postoperative period. Preoperative eosinophil cationic protein mean concentration was < 2 μg/l and mean response value (RV) was 28.80. Pre-operative mean myeloperoxidase concentration was 7.66 ng/ml. Postoperative eosinophil cationic protein mean response value was 63.40 and mean myeloperoxidase concentration was 59.25 ng/ml. There were significant differences between third and final samples with regard to both neutrophil percentages ( p = 0.028) and MPO levels ( p = 0.005). While the preoperative mean PaO2 value was 89.39 mmHg and mean SaO2 value was 97.12%, they were calculated in the postoperative arterial blood specimens of patients, without inhaling O2, as 65.31 mmHg and 93.84%. These changes between blood gas analyses reflect the impairment of the lungs ( p = 0.009 and p = 0.007, respectively). Neither alveolar macrophage viability nor ECP levels changed significantly between consecutive periods. However, when the results of the first and fourth samples were compared, we saw the cumulative effects of CPB, in that alveolar macrophages lost their viability and ECP mean RVs rose. These changes were statistically significant ( p = 0.027 and p = 0.013, respectively). However, postoperative ECP levels were not like those found in a patient with asthma. Also, changes between alveolar macrophage percentages ( p = 0.028), between neutrophil percentages ( p = 0.036) and between MPO concentrations ( p = 0.005) were statistically significant. Again, changes in neutrophil percentages between first and final samples correlated with changes in MPO levels between same periods ( r = 0.657, p = 0.039).
Veno-venous bypass in liver transplantation: heparin-coated perfusion circuits reduce the activation of humoral defense systems in an in vitro model
Authors: Scholz Tim , Solberg Rigmor , Okkenhaug Cecilie , Videm Vibeke , Gallimore Michael J , Mathisen Øystein , Pedersen Thore , Mollnes Tom E , Bergan Anstein , Søreide Odd , Klintmalm Göran B , Aasen Ansgar O 
Published: January 2013

We studied the effects of bypass circuit surface heparinization on kallikrein-kinin, coagulation, fibrinolytic and complement activation in a closed model system for simulating veno-venous bypass (VVBP) in orthotopic liver transplantation (OLT). The circuits were identical to those in routine use during clinical OLT in our institution. Fresh whole human blood diluted 1: 2 with Ringer’s acetate was circulated at a non-pulsatile flow (2 l/min) and at a constant temperature (37.5°C) for 12 h. In 10 experiments, the entire inner surface of the circuits was coated with end-point attached heparin (HC). In the remaining 10, non-treated PVC tubing was used (NC). Components of the plasma kallikrein-kinin, coagulation, fibrinolytic and complement systems were analyzed using functional techniques (chromogenic peptide substrate assays) and enzyme immunoassays at baseline, 3 and 12 h. Significant activation of the initial (C3bc) and terminal (TCC) components of the complement system were found in both the NC and HC groups after 3 and 12 h: C3bc: NC: baseline =4 (3.5-7.7), 3 h=17.3* (12.5-27), 12 h=31* (17.7-63.6), HC: baseline=4.9 (3.2-6.8), 3 h=9* (6-14.4), 12 h=13.7* (7.4-18.1). TCC: NC: baseline=0.4 (0.2-0.6), 3 h=5* (0.8-11.9), 12 h: 13.1* (4.2-25.7). HC: baseline=0.5 (0.1-0.6), 3 h=0.6* (0.1-0.8), 12 h=1.2* (0.3-2) AU/ml; median and range (*: p<0.05). The C3bc and TCC concentrations were significantly higher in the NC group at 3 and 12 h, compared to the HC group: C3bc (NC vs. HC group): 3 h, p<0.001; 12 h, p<0.001. TCC (NC vs. HC group): 3 h, p<0.001; 12 h, p<0.001. Significant increases in the values of thrombin-antithrombin complexes ( p<0.003), prothrombin fragment 1+2 ( p<0.006) and plasmin-α2-antiplasmin complexes ( p=0.016) were found in the non-coated group, but not in the heparin-coated group during the observation period, showing that the coagulation and fibrinolytic systems were activated in the non-coated circuits. We conclude that heparin-coating of the internal surface of the extracorporeal perfusion circuit used for VVBP reduces activation of the plasma cascade systems in a closed venous system in vitro.
Effects of retrograde autologous priming on blood transfusion and clinical outcomes in adults: a meta-analysis
Authors: Sun P , Ji B , Sun Y , Zhu X , Liu J , Long C , Zheng Z 
Published: January 2013

Objective: Reducing the priming volume is an effective means of decreasing hemodilution and blood transfusion during cardiopulmonary bypass (CPB). The patient’s own blood was used to replace the crystalloid in the CPB circuit by retrograde autologous priming (RAP) in order to decrease the priming volume. Therefore, we performed a meta-analysis to investigate whether RAP could reduce blood transfusion and improve clinical outcomes. Materials and Methods: A comprehensive search was conducted for randomized, controlled trials (RCTs) exploring RAP in PubMed, Embase, The Cochrane Library, Google Scholar and Chinese literature databases (WanFang, WeiPu and CNKI). Clinical parameters and outcomes were focused on the lowest hematocrit (Hct) during CPB, the number of patients transfused blood intraoperatively, the number of patients transfused blood perioperatively, the number of blood units transfused, 24-hour chest tube drainage, hours to extubation, length of ICU stay, and length of hospital stay. Results: Ten trials, with a total of 1123 patients, were included. The number of patients transfused blood intraoperatively (RR = 0.39, 95% CI = [0.29, 0.53], p<0.00001, I2 = 40%) and perioperatively (RR = 0.53, 95% CI = [0.43, 0.66], p<0.00001, I2 = 0%) and the number of blood units transfused (SMD = -0.53, 95% CI = [-0.73, -0.33], p<0.00001, I2 = 14%) were all significantly reduced in the RAP group. No differences in the hours to extubation (SMD = -0.11, 95% CI = [-0.33, 0.12], p=0.37, I2 = 0%) and the length of ICU stay (SMD = -0.17, 95% CI = [-0.41, 0.08], p=0.18, I2 = 0%) were observed between the two groups. Conclusion: Compared to conventional priming, RAP could reduce transfusion in adults significantly, but had no effect on clinical outcomes, comparing to conventional priming. Further studies involving RAP are expected to investigate if this technique is beneficial to the patient.