bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative analysis of the effect of pulsatile flow on vascular resistance
Authors: Sohma A. , Ohga K. , Oka T. , Oda Y. , Itoh T. , Morimoto T. 
Published: November 2007

'Pulsatile flow' has been reported to reduce vascular resistance. In this study, the effect of pulsatile flow was assessed quantitatively, using perfusion of canine hindlimb. The perfusion circuit consisted of roller-type pulsatile pump (Cobe Inc., Stockert pump) and bubble oxygenator (Shiley Inc., S-070/s). Each flow curve was quantified with the mean flow rate (F) and pulse power index (PPI). PPI is derived by Fourier transformation of the flow curve and represents the degree of 'pulsation'. Vascular resistance was determined during perfusion with varied flow rate and PPI. The regression formula between vascular resistance (VR) and two parameters was obtained as follows: VR(F,PPI) = 41600x(F-1.37) -0.95+913 - PPIx{(3.99x(F-1.33)-040_0.69} where VR is measured in mmHg. min-1.kg.ml-1; F represents ml.min-1.kg -1 (range from 2.8 to 17.1); and PPI is dimensionless (range from 2.8 to 215.7). Using this formula, vascular resistance at a fixed flow rate and wave form can be predicted. When the flow rate is 6.27 ml.min-1.kg-1 and the PPI is 1466, (measured values under perfusion with own beating heart) the vascular resistance perfused by own beating heart is obtained. The results indicate that the pulsation of own beating heart contributes to a reduction in vascular resistance to 80%. It is also shown that the value of PPI which is necessary to reduce the vascular resistance to 80% is more than 1300 under the normal flow rate range.
Partial left heart bypass with centrifugal pump and limited anticoagulation during the resection of coarctation of the aorta
Authors: Everts Pam , Schönberger Jpam , Steenbrink J. , Bredée JJ 
Published: November 2007

Resection of coarctation of the aorta necessitates crossclamping of the descending aorta. Despite the existence of a collateral circulation, spinal cord ischaemia and intestinal ischaemia may occur associated with a prolonged crossclamp time and distal hypoperfusion during the operation. To prevent these severe complications and to control hypertension proximal to the clamp, circulatory support may be necessary. We performed partial left heart bypass (PLHB) with limited anticoagulation in four patients, using a centrifugal pump in orderto sustain a mean arterial blood pressure of at least 60mmHg in the distal thoracic aorta below the clamped coarctated segment. The method is practical, simple and safe. It combines features of several methods of protection of the spinal cord: adequate distal perfusion of the aorta at a desired flow rate and blood pressure, avoidance of proximal hypertension, minimal aortic and cardiac manipulation and avoidance of bleeding tendency by limited heparinization. Vasodilating drugs with their adverse effect on distal aortic pressure are not necessary in this situation. Postoperatively, neurological sequelae orvital organ damage did not occur in our patients.
Conventional cardiopulmonary bypass in neonates. A physiological approach -10 years of experience at Marie-Lannelongue Hospital
Authors: Nicolas Françoise , Daniel Jean-Pierre , Bruniaux Jacqueline , Serraf Alain , Lacour-Gayet François , Planche Claude 
Published: November 2007

There is still controversy about the optimal method of venoarterial cardiopulmonary bypass (CPB) for correction of congenital heart diseases in neonates and young infants. High rates of CPB-related morbidity and mortality are still reported. Since 1980, conventional CPB with double caval cannulation with right-angled cannulae has been used in the high majority of neonates at Marie-Lannelongue Hospital. The extracorporeal circuit was miniaturized to be primed with a volume as small as possible. Priming (500 ml) was done with packed red cells and fresh frozen plasma. CPB was conducted at 30% haematocrit and normal ranges of flow rate, arterial pressure, systemic vascular resistances and oxygen delivery. These normal physiological parameters were also maintained during hypothermia. During the last two years, 151 neonates below 15 days old who underwent open-heart surgery were reviewed. The overall hospital mortality was 7.24%. None of the survivors had postoperative complications related to CPB. All physiological and biological values remained within normal ranges during the postoperative course.
A guideline nomogram to control intraoperative haemodilution in cardiac surgery
Authors: Ranucci M. , Conti D. 
Published: November 2007

Intraoperative blood collection prior to cardiopulmonary bypass (CPB) is a common procedure in cardiac surgery. Its aims are to obtain fresh whole blood to be infused after CPB, to use autologous blood in the prime or to avoid too high levels of haematocrit (HCT) during CPB. Calculations to determine the amount of blood to be collected are generally based on theoretical assumptions. In this paper we have set up and controlled, on a clinical basis, a nomogram to be used in order to obtain a standard pre-CPB HCT equal to 38%, using a moderately hypervolaemic haemodilution based on blood collection simultaneous with fluid replacement. Thirty adult patients were evaluated in order to settle the nomogram; subsequently, the nomogram validity was checked on 100 adult patients. Statistical analysis revealed the good clinical usefulness of this instrument.
D-901 neonatal oxygenator: a new perspective
Authors: De Somer F. , François K. , Foubert L. , Deryck Y. , De Smet D. , Vanackere M. , Van Nooten G. 
Published: November 2007

Five infants with congenital heart disease were perfused with the D-901 neonatal oxygenator at the time of their cardiac surgery. The ability to reduce the prime volume below the blood volume as well as the blood handling and gas transfer characteristics were studied. In all cases the prime volume was less than or equal to the blood volume of the patient. This resulted in a reduction in the use of homologous blood products. Due to the concept of the D-901 it was possible to adapt the tubing in such a way that a complete prime of 220 ml was obtained. The device had a maximum oxygen transfer of 45 ml/min. The maximum carbon dioxide removal was 50 ml/min at a blood gas ratio of one. The mean platelet count post bypass decreased to 91 % of the baseline value. Mean free haemoglobin levels increased to 86 mg/100 ml at 120 minutes of bypass. We conclude that the D-901 oxygenator opens new perspectives for perfusion in small babies in terms of priming volume and use of homologous blood products while maintaining good gas transfer characteristics. However, larger series are necessary to expand our experience with this device and its limitations. No specific problems related to the device were encountered and all infants had an uneventful postoperative course.
Studies of the effect of Pall leucocyte filters LG6 and AV6 in an in vitro simulated extracorporeal circulatory system
Authors: Thurlow PJ , Doolan L. , Sharp R. , Sullivan M. , Smith B. 
Published: November 2007

Neutrophil activation is thought to play a major role in the inflammatory response seen in reperfusion injury and similar clinical situations, i.e. extracorporeal circulation. lmpairment of neutrophil function or reduction of total numbers of neutrophils using a leucocyte filter may be beneficial in reducing the adverse clinical effects. In this study we have investigated the effect of the Pall LG6 and control AV6 filters during simulated in vitro cardiopulmonary bypass (CPB). Various parameters were evaluated including neutrophils, total leucocytes, monocytes, lymphocytes and platelets, expression of antigens on neutrophils using a panel of leucocyte-associated monoclonal antibodies CD13, 14, 15, 45Ro, 67,11a, 11 b and L selectin. The effects of leucocyte stimulation with phorbol myristate acetate (PMA) and a leucocyte bolus from a patient with chronic myeloid leukaemia (CML) were also investigated. We have demonstrated that the LG6 significantly reduces leucocytes, in particular neutrophils, with a modest reduction of lymphocytes, platelets and haematocrit, whereas the AV6 had no effect on leukocytes or neutrophils in the test system. In addition the LG6 was associated with a reduction in expression of all leucocyte antigens by approximately 20%; however there was no appreciable alteration of any of the antigens with AV6. Leucocyte stimulation with PMA resulted in a dramatic decrease of all cellular elements and an extra leucocyte load (using CML leucocytes) was not effectively filtered by the LG6 filter. These studies identify the capacity of the LG6 as compared with the AV6 to deplete activated neutrophils in an in vitro simulated cardiopulmonary bypass circuit.
Carmeda surface heparinization in neonatal ECMO systems: long-term experiments in a sheep model
Authors: Palmér K. , Ehrén H. , Benz R. , Frenckner B. 
Published: November 2007

The thromboresistance in three Carmeda (Stockholm, Sweden) heparin- coated neonatal ECMO systems with a runtime of 45, 56 and 96 hours, respectively, and three noncoated systems with a runtime of 12, 42 and 66 hours, respectively, were compared using a sheep model. The flow rate was 200 ml/min and the activated clotting time (ACT) was kept at approximately 120 seconds. At the end of the experiment, the heparin-coated systems only contained minimal clotting while the controls showed major clotting in the entire system. Fibrin monomers were not detected until after 24 hours in the heparin- coated group, but demonstrated within 60 minutes in the noncoated group. It is concluded that the Carmeda heparin coating has a thromboresistant effect, and may be used to reduce the need for systemic heparinization in ECMO treatment of neonates.
Paediatric perfusion practice in North America: an update
Authors: Groom Robert C , Hill Aaron G , Kurusz Mark , Munoz Ruben , McGowen Kelley J , Resley Justin J , Akl Bechara F , Speir Alan , Lefrak Edward A 
Published: November 2007

In August 1994, an updated survey questionnaire was mailed to each paediatric open-heart surgery programme in North America as a follow-up to the 1989 paediatric survey. The survey requested demographic data, equipment selection criteria and specific perfusion techniques for paediatric patients. The earlier survey revealed a wide range of clinical practice. Data from the recent survey were compared with the 1989 survey to identify current programme demographics and trends in equipment use and techniques. Responses were received from 125 hospitals (110 active programmes and 15 programmes that do not perform paediatric open-heart surgery) for a response rate of 74%. Of the 110 active centres, 77 perform both adult and paediatric cardiac surgery, and 33 perform paediatric surgery exclusively. Forty-three centres reported that they perform paediatric cardiac transplantation, an increase from 35 centres in 1989. Total caseload increased by more than 8% per year from 1988 to 1994. In 1994, 18% of the patients were operated upon during the first month of life (versus 15% in 1989), and 46% were operated on during the first year of life (versus 45% in 1989) While the 1989 survey was characterized by a high degree of heterogeneity in equipment and techniques, the recent survey reveals a trend toward homogeneity among respondents. The use of membrane oxygenation and arterial line filtration has become universal, and there was an increase in the use of all types of safety devices in the cardiopulmonary bypass circuit.
A comparison of albumin, polygeline and crystalloid priming solutions for cardiopulmonary bypass in patients having coronary artery bypass graft surgery
Authors: Scott DA , Hore P.J. , Cannata J. , Mason K. , Treagus B. , Mullaly J. 
Published: November 2007

This study was designed to assess the effect of different prime solution compositions on a patient's fluid balance, transfusion requirements, renal function and haemodynamic stability over the first 24 hours postbypass. Ninety-three patients presenting for first-time coronary artery bypass graft (CABG) surgery were randomly allocated to receive one of three prime solutions for the CPB pump: albumin (4.6%) + Plasmalyte (Group A, n = 32), polygeline (Hemaccel) + Plasmalyte (Group P, n = 29), or crystalloid (Plasmalyte) alone (Group C, n = 32). Patients, anaesthetists, surgeons and intensive care unit (ICU) staff were all blinded as to the solution type. The groups were demographically and haemodynamically similar. There were no differences between the groups with respect to white cell or platelet counts during the study. There was a significant difference in haemoglobin levels between the groups on weaning from CPB and on arrival in the ICU (Group C > Groups P and A, p < 0.001 for both times). There was no difference in blood transfusion requirements between any of the groups. During CPB, Group C required significantly more crystalloid than the other groups (p < 0.001). Urine output was significantly higher in Group C compared with Groups P and A at all time periods up to and including ICU 12 hours (p < 0.05). The use of frusemide was significantly higher in the ICU in Groups P and A (p < 0.01). There was a net gain of 3132 ± 412 ml in Group C in 24 hour fluid balance, which was significantly higher than Group A (2166 ± 223 ml, p = 0.04). Our results show that, in this patient population, there is no advantage in using a colloid-based prime solution over a purely crystalloid solution from a haemotologic or haemodynamic point of view for the first 24 hours after CPB. There appears to be an increase in extracellular fluid (ECF) retention in Group C, but this caused no related problems in the study period. On the other hand, diuretics (frusemide) needed to be given significantly less often in these patients to offset oliguria.
Normalization of experimental results with respect to inlet conditions in membrane oxygenator testing
Authors: Costantino ML , Fiore GB 
Published: November 2007

This study looked at the problem of the excessive variability in oxygenator testing results, induced by variation of inlet parameters, particularly of inlet oxyhaemoglobin saturation. The investigation was carried out in the laboratory. An in vitro circuit was used to perfuse a small oxygenating cell. Blood flow rate (BFR) and film thickness (BFT) were varied to obtain different oxygenation conditions, while the inspired oxygen fraction (FiO 2) and ventilation ratio were kept at constant values. With each test condition, inlet saturation was varied in the range 60-70% and a number of veno-arterial blood samples (at least 20) were withdrawn and analysed for numerical computing and statistical analysis. The generic law relating oxygenation increment to inlet saturation was found. This allowed a useful normalization procedure to be applied to oxygenator testing results and render them comparable, even if obtained at different inlet conditions.
The activated clotting time loading dose response ratio (ACTLORR) as an indicator of heparin demand during cardiopulmonary bypass
Authors: Reece Ian J , Linley Gerrard , Al Tareif Habib , DeVroege Rollie , Tolia Jitesh , Sheth Jayesh 
Published: November 2007

Data relating to the activated clotting time response to a 4 mg/kg heparin loading dose were collected prospectively in 358 patients having cardio pulmonary bypass. After excluding patients with factors known to cause relative heparin resistance or sensitivity, the activated clotting time (ACT) loading dose response ratio (ACTLORR) was calculated retrospectively in 263 patients and found to correlate significantly (p = 0.0001) with the need for extra heparin administration during bypass. Where the ACTLORR was above 5.5, 92% of patients required no additional heparin during the first 90 minutes of bypass (n = 98). Where the ACTLORR was between 4.0 and 5.0, it was far less predictive, with approximately 35% of patients requiring additional heparin. This study indicates that a large ACT response to the initial heparin loading dose (a high ACTLORR) is predictive of stable, adequate anticoagulation during the first 90 minutes of bypass, but that a low initial response is not necessarily associated with declining ACTs and the need for additional heparin administration.
Review on the multifactorial aspects of bioincompatibility in CPB
Authors: Daniel Serge 
Published: November 2007

'In cardiopulmonary bypass as applied to open heart surgery, we are no longer looking for improving one thing 100% but improving everything by 1 %.' Adapted from Mr Carlson, CEO, Scandinavian Airlines. Over the last few years, a great emphasis has been placed on the bioincompatibility of foreign, nonphysiological materials used during CPB. It is only recently that bioincompatibility has objectively been recognized to be multifactorial, with the dominant implicated sources being cardiotomy blood suction, shear stresses or flow dynamics and, to a lesser degree, the blood/artificial surface interactions, the heparin/protamine complex and the various forms of emboli or debris. In summary, in CPB, the reduction of postoperative complications, such as whole body inflammatory reactions, bleeding and organ dysfunctions, can only be impacted if the primary, dominant sources of bioincompatibility are reduced or eliminated.
Efficacy and safety of aprotinin in aortocoronary bypass and valve replacement operations: a placebo-controlled randomized double-blind study
Authors: Rodrigus IE , Vermeyen KM , De Hert SG , Amsel BJ , Walter PJ 
Published: November 2007

To assess the efficacy and safety of the use of a high-dose regimen of aprotinin in routine cardiac operations, a placebo-controlled randomized double- blind study was conducted in 93 adult patients undergoing cardiopulmonary bypass. Aprotinin-treated patients (group A, n = 46) received 2 × 106 Kallikrein Inactivating Units (KIU) of aprotinin before incision, 2 × 106 KIU in the priming solution and 5 x 105 KIU/h during CPB. Control patients (group B, n = 47) received the same volume of normal saline. Mean postoperative blood loss in ml after six hours and in total until removal of thoracic drains decreased significantly from 752 and 1933 in controls, to 358 and 1051 in treated patients ( p < 0.001). Mean total transfusion needs were 2.6 (A) and 4.8 (B) units per patient. Adverse events were evenly distributed between both groups and could not be attributed to aprotinin use. We, therefore, recommend the use of a high-dose regimen of aprotinin for routine cardiac operations despite its cost.
Troponin T release with warm and cold cardioplegia
Authors: Brackenbury ET , Sherwood R. , Meehan N. , Whitehorne MA , Forsyth AT , Marrinan MT , Desai JB 
Published: November 2007

Cardiac troponin T (cTnT) levels were measured in 41 patients undergoing elective coronary artery surgery. Twenty-one patients received continuous warm antegrade blood cardioplegia to maintain asystole whilst 20 patients received antegrade cold blood cardioplegia intermittently. Serum levels of cTnT were determined preoperatively and at 0, 6, 12 and 18 h postbypass. Peak cTnT levels and total cTnT release (calculated from the area under the curve postoperatively) were found to be significantly higher (p < 0.05: Mann-Whitney) when cold cardioplegic solutions were used. Continuous warm cardioplegia results in lower cTnT release than intermittent cold blood cardioplegia suggesting that the former may provide better myocardial preservation.
The effect of fast-tracking on neurological complications post-cardiopulmonary bypass
Authors: Palanzo David A , Zarro Debra L 
Published: November 2007

With the push to get patients through the system in five days, most patients undergoing nonemergency coronary artery bypass grafting (CABG) are being 'fast-tracked'. Using this anaesthetic regimen appears to keep patients less anaesthetized (light) during cardiopulmonary bypass (CPB) than when using our previous regimen. This is manifested by higher mean arterial pressures (maintained above 65 mmHg) during CPB. If patients are receiving less anaesthesia during CPB, they may have an increased cerebral metabolism. This could lead to decreased cerebral oxygenation with a resultant neurological deficit postoperatively. A retrospective analysis of 200 patients who underwent nonemergency CABG was conducted to evaluate postoperative neurological complications The patients were matched by surgeon, procedure and CPB time. They were separated into two groups: group 1 had maintained mean arterial pressures greater than 65 mmHg on CPB (n = 100) and group 2 had pressures less than 65 mmHg (n = 100). Group 1 had two patients (2%) who exhibited neurological complications after CPB (delirium, continuous coma for at least 24 h) with both of these patients previously having noted cerebrovascular disease. Group 2 also had two patients (2%) with postoperative neurological complications (delirium, transient stroke) with one patient having cerebrovascular disease. From our study, we cannot say that fast-tracking increases the risk for postoperative neurological complications This could be due to the fact that we maintained the mean venous oxygen saturation during CPB above 70%. More specific testing needs to be done to truly rule out any negative postoperative effect.
Review article : Emesis in the patient with advanced cancer
Authors: Allan Simon G 
Published: November 2007

The control of symptoms related to far advanced cancer has improved dramatically in recent years, making the passage of death more tolerable for such patients. The major impact of analgesic control now allows research efforts to focus on other distressing symptoms such as nausea and vomiting. The emetic process is a complex physiological and psychological one of multifactorial aetiology. Rapid improvement in our understanding of these processes is allowing the more rational use of known antiemetics and the development of new antiemetic agents. A rapid expansion of the literature of cytotoxic-induced emesis has pointed to new antiemetic agents and new schedules of administration. This review emphasises the need to identify the cause of emesis before attempting indirectly to block the emetic process with antiemetic drugs. It also outlines the many areas where research could be applied to unravel some of the questions about which antiemetic to use, in what dose, and perhaps to identify the main site of emetic stimulus. More effective research is required, but the outlook for improved control of nausea and vomiting in the terminally ill patient is good.
Inadequacies of care in far advanced cancer patients: a comparison between home and hospital in Italy
Authors: Toscani Franco , Mancini Claudio 
Published: November 2007

A previous survey of patients treated by our palliative care service showed that most patients with advanced cancer wished to be cared for at home. This is in contrast with the fact that these patients were increasingly frequently hospitalized because of their belief that a hospital, in spite of its shortcomings, is the place where medical and nursing care are more advanced. A prospective survey was carried out on 120 advanced cancer patients under the palliative care service of the Cremona Hospital, Italy. The survey recorded all the inadequacies of their care from the time patients were seen until death occurred. Five times as many inadequacies occurred in hospital than at home (an average of 4.4 ± 5.0 every 100 days against 0.8 ± 2.0 every 100 days; p < 10 E -6). The most frequent inadequacies of care at home were caused by both narcotic and drug misuse, and unjustified alterations in the therapy; in the hospital they were related to therapeutic regimes and failure to report new symptoms. These data support the view that general hospital care in Italy today does not necessarily provide the best solutions to the problems of the terminally ill patient. A palliative care programme should include the option of organized home care.