bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of postoperative normovolaemic anaemia and autotransfusion on blood saving after internal mammary artery bypass surgery
Authors: Schönberger Jacques PAM , Everts Peter AM , Bredee Johan J , Jansen Evert , Goedkoop Rene , Bavinck Johan H , Berreklouw Eric , Wildevuur Charles RM 
Published: November 2007

The efficacy of two blood conservation techniques in decreasing and in preventing the use of homologus blood products was retrospectively studied in 150 patients undergoing internal mammary artery bypass surgery. Patients were matched according to prebypass blood haemoglobin (Hb) content and body surface area and were allocated to one of three groups: in the patients of group 1 (n = 50), normovolaemic anaemia (NA) was accepted postoperatively (haematocrit [Hct] was accepted to a minimum level of 25%); the patients of group 2 (n = 50) were treated with postoperative autotransfusion (AT) of mediastinal shed blood and acceptance of NA. Group 3 (n = 50) contained control patients, not treated with NA or with AT (Hct was accepted to a minimum level of 30%). Patients of group 1 required 3.0 ± 0.3 units of homologous blood products, but the patients of groups 2 and 3 received significantly more (p <0.01 ) units: 3.9 ± 0.2 and 4.5 ± 0.3 units. No donor blood products were needed in 36%, 9% and 5% of the patients in groups 1, 2 and 3 respectively. The net postoperative blood loss was similar in the groups: 1229 ± 92 ml in group 1, 1098 ± 74 ml in group 2 and 1243 ± 72 ml in group 3. However, total blood loss (1982 ± 135 ml), including the retransfused part (954 ± 89 ml), was significantly larger (p <0.01) in group 2, than in groups 1 and 3. We conclude that NA alone is more effective than the combination of NA and AT of large amounts of shed blood in reducing and in preventing the need for homologous blood products in internal mammary artery bypass surgery. When AT of a large amount of shed blood is employed in addition to NA, increased bleeding is observed.
Do plasma catecholamines influence microcirculatory blood flow in cardiac surgery patients?
Authors: Boldt J. , Zickmann B. , Ballesteros M. , Herold CH , Dapper F. , Hempelmann G. 
Published: November 2007

To investigate whether plasma catecholamines influence blood flow on the microcirculatory level, forehead and forearm skin blood flow was measured by a two-channel laser Doppler blood flux monitor in 50 patients undergoing aortocoronary bypass grafting. Macrohaemodynamics, plasma viscosity, and skin temperatures were additionally monitored. Plasma catecholamines (adrenaline [AD] and noradrenaline [NOR] ) were determined using high-pressure liquid chromatography (HPLC) from arterial blood samples. In the prebypass period, blood concentrations of both catecholamines increased slightly showing a wide range of values (AD ranging from 3 to 955 pg/ml; NOR ranging from 27 to 5326 pg/ml). In spite of the tremendous increase in plasma catecholamines before and after bypass, laser Doppler flow (LDF) remained almost stable in this period. Neither LDF nor macrocirculatory parameters were correlated to plasma catecholamines. Cardiopulmonary bypass (CPB) resulted in a significant increase in catecholamines (AD ranging from 80 to 2480 pg/ml; NOR ranging from 188 to 9898 pg/ml). Although haematocrit and plasma viscosity were significantly reduced during CPB, LDF decreased in comparison to baseline values (LDF forehead: -25%; LDF forearm: -35%) ( p<0.05). It is concluded that plasma catecholamine levels were markedly changed during cardiac surgery showing a wide range of concentrations. Microcirculatory flow assessed by laser Doppler remained almost unaffected by these alterations and was not correlated to AD or NOR plasma concentrations. However, during CPB a significant increase in catecholamines can contribute to the risk of microperfusion abnormalities which can be assessed by laser Doppler technique.
Effect of prostacyclin PGl2 on cardiopulmonary bypass- induced lung injury
Authors: Fessatidis I. Th. , Brannan J.J. , Taylor K.M. , Kanellaki-Kyparissi M. , Abdulla A.K. , Olsen E.C.J. 
Published: November 2007

Lung injury produced by cardiopulmonary bypass (CPB) is clinically characterized as postperfusion pulmonary dysfunction syndrome. The roles of humoral factors, altered perfusion modes and the occurrence of diffuse microembolism have been subjects of a number of studies. This paper presents the effectiveness of a platelet inhibiting drug, PGl2, in preventing occlusive microaggregates in the pulmonary circulation. In a series of experimental dog studies using a PGI2 dosage protocol of 10 ng/kg/minute for 30 minutes prior to the onset of CPB followed by 20 mg/kg/minute during CPB, the following effects have been observed: 1) Preservation of platelet numbers during CPB (p<0.01 versus controls; n = 16). 2) Significant reduction in platelet aggregation during CPB (p <0.01; n = 16). 3) Insignificant hypotensive effect at normal levels of peripheral vascular resistance (n = 16). 4) Occlusive fibrin, leucocytes and small platelet-based microaggregates obstructing pulmonary arterioles in six of the seven control dogs but in none of the dogs receiving PGl 2 infusion. 5) No evidence of perivascular or intra-alveolar oedema, interstitial inflammatory cell infiltrates or haemorrhage was seen in either group of dogs. The controversy existing in relation to the possible therapeutic role of PGl2 and, in particular, its ability to prevent occlusive microaggregates in the arterioles and capillaries of vital organs should encourage further clinical studies of PGl2 and its derivatives during cardiac surgery.
Risk factors for renal dysfunction after coronary surgery: the role of cardiopulmonary bypass technique
Authors: Ranucci Marco , Pavesi Marco , Mazza Ermanno , Bertucci Carla , Frigiola Alessandro , Menicanti Lorenzo , Ditta A. , Boncilli A. , Conti Daniela 
Published: November 2007

We studied 316 patients undergoing cardiopulmonary bypass for coronary artery surgery in order to determine perioperative risk factors for postoperative renal dysfunction A preliminary univariate analysis was performed by χ2 analysis for categorical data and Mann-Whitney U-test for continuous variables to detect significant correlations between each risk factor and the occurrence of moderate or severe renal dysfunction. Subsequently, a multiple logistic regression was applied to the three risk factors identified as predictive for severe renal dysfunction. Low cardiac output syndrome and need for banked blood transfusions combined with a low haematocrit value during cardiopulmonary bypass increase the probability of severe renal dysfunction in the postoperative course.
Determination and comparison of heat exchange efficiency of four commercially available blood cardioplegia sets
Authors: Hundley David S , Vertrees Roger A , Brownstein Louis , Clancy Michael , Garwood Alexander P , DeiRossi Anthony J 
Published: November 2007

An in vitro comparison of the heat exchange properties of the Electromedics D1081A, Sarns MP-4 'Conducer Coil' 165720, Bentley HE-1 00 and the Shiley BCD Plus 4:1 blood cardioplegia sets was performed. The efficiency was calculated for each heat exchanger and post-heat exchange blood path temperatures were compared. The calculated efficiency for each heat exchanger is as follows: Electromedics D1081A at 18 I/minute coil water flow (0.95); Sarns MP-4 165720 at 9 I/minute coil water flow (0.93); Bentley HE-100 at 10 I/minute coil water flow (0.91); Shiley BCD Plus at 15 I/minute coil water flow (0.90). Blood path, precoil temperatures for each unit were compared statistically with no differences found ( p > 0.05). Blood side, postcoil temperatures were then compared. The average postcoil blood path temperature of the Electromedics D1081A was 1.6° ± 0.1 °C, of the Sarns MP-4 165720 it was 2.1 ± 0.1°C, of the Bentley HE-100 it was 2.7° ± 0.3°C, and the Shiley BCD Plus 3.0° ± 0.4°C. The results of this experiment indicate that the average postcoil temperature of the Electromedics D1081 A was lower than the Sarns MP-4 165720 ( p < 0.05) which was lower than that of the Bentley HE-100 ( p < 0.05) and Shiley BCD Plus ( p < 0.05). No statistical difference was found between the average postcoil temperature of the Bentley HE-1 00 and the Shiley BDC Plus.
Clinical evaluation of the Medtronic Maxima Plus membrane oxygenator
Authors: Fried David W , DeBenedetto Benjamin N , Zombolas Theodore L , Leo Joseph J 
Published: November 2007

The purpose of this study was to clinically evaluate the degree of improvement, if any, in the oxygen transfer performance of the recently released Medtronic Maxima Plus membrane oxygenator. The outside diameter of the hollow fibres was reduced, increasing the membrane surface area from 2.0 m2 to 2.3 m2 without altering the polycarbonate housing. Maximum extrapolated oxygen transfer of the Maxima Plus (444 ml O2/minute) was increased 23.68% when compared to the Maxima (359 ml O2/minute). When expressed per metre squared of membrane surface area, the Maxima Plus had an increase of 13.5 ml O2/m2/Minute (7.24%) over the Maxima. Pressure drop across the Maxima Plus was within 3.5 mmHg of the Maxima over the range of clinical blood flows indicating that the fibre bundle packing density was not significantly altered. Oxygen transfer consistency, expressed as a function of the standard deviation of oxygenator performance index values, was not significantly different for the two oxygenators. We concluded that the improvement in total oxygen transfer was due to an increase in membrane surface area as well as enhanced transfer efficiency per metre squared. We believe that the improved oxygen transfer performance was accomplished without impacting significantly upon the other attributes of the oxygenator (e.g., pressure drop, consistency, priming volume).
Cardiopulmonary bypass with adequate flow and perfusion pressures prevents endotoxaemia and pathologic cytokine production
Authors: Quigley RL , Caplan MS , Perkins JA , Arentzen CE , Alexander JC , Kuehn BE , Hoff WJ , Wallock ME 
Published: November 2007

Endotoxin and cytokine inflammatory mediators comprise the afferent and efferent limbs of the 'acute phase response'. During cardiopulmonary bypass (CPB) there may be gut translocation of endotoxin and contact activation of lymphocytes. It has been hypothesized that the haemodynamic instability encountered following CPB is caused by the 'acute phase response'. In this study we attempted to quantify the acute phase response in patients undergoing open-heart surgery and determine the influence of these cytokines on perioperative morbidity. Four perioperative blood samples were drawn from 20 consecutive patients undergoing coronary artery bypass grafting (CABG). These samples were assayed for endotoxin and four cytokines. In all cases the cardiac index was maintained > 2.4 l/min/m 2 during nonpulsatile normothermic bypass (37°C) and > 1.8 l/min/m 2 during nonpulsatile hypothermic bypass (28°C), and the perfusion pressure > 60 mmHg. Endotoxin was not detected in any of the test samples despite positive nonpatient controls. Interleukin 6 (IL-6) and tumour necrosis factor (TNF) were not detected despite an assay sensitivity of 80 and 10 pg/ml, respectively. TNF was detectable with an assay sensitivity of 0.5 pg/ml although there were no significant differences within the group. Interleukin 1 (IL-1) was detected (range = 0.98 - 9.09 ng/ml) in patients and again there were no trends within the group. The platelet activating factor (PAF) values peaked at crossclamp release (1.3 ng/ml versus a baseline of 0.2 ng/ml); however, there was no significant difference within the study. The perioperative rise in PAF suggests that of all the mediators assayed this cytokine has the lowest synthesis threshold in response to stress, related to nonpulsatile CPB, and is unrelated to endotoxaemia (as detected by the limulus amoebocyte lysate (LAL) assay). Despite recent reports outlining the incidence of endotoxaemia, cytokine activation and the benefits of anti inflammatory therapy during CPB, our data suggest that maintenance of high flow and perfusion pressures during nonpulsatile CPB reduces the incidence of any 'acute phase response' of clinical significance.
The haemostatic effectiveness of autologous platelet rich plasma sequestered after heparin administration and institution of cardiopulmonary bypass
Authors: Quigley RL , Perkins JA , Caprini JA , Haney El , Switzer SS , Wallock ME , Hoff WJ , Kuehn BE , Arentzen CE , Alexander JC 
Published: November 2007

Preoperative harvesting and postoperative reinfusion of autologous platelet rich plasma (PRP) has been reported to decrease blood loss as well as the requirement for homologous blood transfusion following cardiopulmonary bypass (CPB). We have developed a technique of intraoperative PRP sequestration which occurs during the initial period of CPB after the patient's circulation is supported and heparin has been given (PRP+). This process does not require any additional hardware, personnel or expense and it is performed without difficulty or complication. To evaluate the effect of PRP+ sequestration and reinfusion on blood loss and homologous blood requirement after CPB, we randomly assigned 126 consecutive patients undergoing elective open heart surgery into the experimental group 1 (PRP+) (n = 64) or the control (no platelet pheresis) group 2 (n = 52). A third group (n = 10) were not included in the randomization. Patients in group 3 had PRP prepared by conventional techniques (PRPc) prior to heparin administration and given to the patient after protamine infusion. Aggregation and activation studies were performed on the PRP+, PRPc, and blood bank platelets (BBP). Per cent aggregation of PRP in response to ADP was superior to that of BBP. There were no significant differences in ADP induced aggregation between PRP+ and PRPc. There was no significant difference in platelet activation (CD62) or number between the three groups. Patients infused with PRP+ showed significantly increased aggregation to ADP when compared with untreated patients 120 minutes after return to the ICW. Furthermore, more homologous haemostatic components (platelets/fresh frozen plasma) were required in the control group. We have demonstrated that collection of autologous PRP+ after administration of heparin does not interfere with its haemostatic effectiveness compared with PRPc prepared before the initiation of bypass. Moreover, this can be performed universally in haemodynamically unstable patients without any additional costs.
The effects of congenital heart disease and cardiac surgery on I iver blood flow in children
Authors: Mitchell Ian M , Pollock James CS , Jamieson Morgan PG 
Published: November 2007

Children with congenital heart disease may have some degree of hepatic impairment, with further impairment developing shortly after surgical correction of the cardiac defect. The redistribution of organ blood flow that occurs during cardiopulmonary bypass implicates ischaemia as one of the principal causes of injury. The aim of this study was to measure liver blood flow in children with congenital heart disease and to determine both the effects of cardiopulmonary bypass and the consequences of corrective surgery. Indocyanine green clearance and auricular densitometry, were used in 31 children. In 83% we demonstrated a reduced liver blood flow, with a mean percentage disappearance rate (PDR) of 12.9% (SEM ± 1.2). This finding was unrelated to the patient's age, the type of congenital heart defect or the presence or absence of cyanosis. During cardiopulmonary bypass, hepatic perfusion was further reduced in 77% of children, by an average of 67%, out of proportion with the iatrogenic reduction in total body flow. Six hours after surgery, liver blood flow had increased significantly above preoperative levels (p< 0.001; t-test) to approximately normal values with a mean PDR of 20.4% (SEM ± 1.5).
Regional cerebral oxygenation during cardiopulmonary bypass
Authors: Baris Ronald R , Israel Andrew L , Amory David W , Benni Paul 
Published: November 2007

A significant number of patients suffer transient neuropsychological dysfunction after coronary artery bypass graft (CABG) surgery. Recent studies have implicated reduced levels of O2 supply/demand ratio during the rewarming phase of cardiopulmonary bypass (CPB). Using a near infrared spectroscopy (NIRS) system that permits continuous noninvasive monitoring of regional cerebral O2 saturation (rSO2), we investigated rSO2 during CPB. Following Institution Review Board approval and informed consent, 10 patients undergoing elective CABG were studied. Nonpulsatile CPB with a membrane oxygenator, haemodilution and alpha-stat pH management was used. The NIRS system consisting of two low-power laser diode sources (780 nm and 810 nm) with a photodetector placed on the frontal cortex was used to measure continuously haemoglobin, oxyhaemoglobin and cerebral blood volume. Continuous rSO2 measurements were obtained before, during moderate hypothermia, and during the rewarming phase of CPB. A rSO2 < 50% was defined as abnormal. Onset of rSO2 < 50% was at 32°C, and the highest incidence occurred during the late stages of rewarming (35-37°C). On rewarming from hypothermic CPB, 70% of our patients sustained a rSO2 < 50% for an average total duration of 9.3 minutes, primarily at the end of the rewarming period. This suggests a transient global imbalance in cerebral O2 supply and demand in a large percentage of patients during the rewarming phase of CPB. However, it has not been determined how long a rSO2 < 50% can be permitted before neuropsychological dysfunction is induced. Additional studies correlating psychometric testing with rSO2 measurements should prove useful in detecting episodes of impaired cerebral oxygenation, and help define rewarming protocols.
The relationship between systemic oxygen uptake and del ivery during moderate hypothermic cardiopulmonary bypass: critical values and effects of vasodilation by hydralazine
Authors: Cavaliere F. , Gennari A. , Martinelli L. , Zamparelli R. , Schiavello R. 
Published: November 2007

The relationship between oxygen delivery (DO2) and uptake (VO2) has been studied during moderately hypothermic cardiopulmonary bypass (CPB) in 15 patients undergoing myocardial revascularization. As soon as nasopharyngeal temperature was lowered to 32°C, blood flow was decreased from 2.4 to 2.0 l/min/m 2. Arterial and mixed venous blood gas analyses were performed five and eight minutes later and DO2 and VO2 were calculated; VO2 stabilized in five minutes after changing blood flow and neither DO2 nor VO2 values changed three minutes later (DO 2: 217 ± 19 versus 215 ± 17 ml/min/m2; VO2: 63 ± 12 versus 66 ± 14 ml/min/m2). Blood flow then was increased to 2.3 l/min/m2 and DO2 and VO2 were determined again, five minutes later; they both increased significantly, to 243 ± 20 and 74 ± 13 ml/min/m 2, respectively. However, a further blood flow increase to 2.6 l/min/m 2 which caused DO2 to increase to 277 ± 24 ml/min/m 2, did not affect VO2 which was unchanged five minutes later (76 ± 13 ml/min/m2); VO2 dependence on DO2 values higher than 243 ± 20 ml/min/m2 was consequently ruled out. Ten patients, having a mean arterial pressure higher than 80 mmHg, were eventually vasodilated with hydralazine, 0.1 mg/kg intravenously, and DO2 and VO2 were determined after five and ten minutes. As blood flow did not change, DO2 was unaffected while a slight increase in VO2 mean values was observed which was not statistically significant (prior to hydralazine: 78 ± 15 ml/min/m2; five minutes later: 82 ± 17 ml/min/m2; 10 minutes later: 76 ± 18 ml/min/m2). In conclusion, during hypothermic CPB at 32°C, VO2 plateau ranges between 48 and 102 mi/min/m 2 (mean ± 2 SD) in 95% of patients, corresponding to 66 and 141 ml/min/m 2 at 37°C; this finding closely matches other literature reports. Consequently, lower VO2 values suggest inadequate oxygen supply to tissues. Critical DO2 at 32°C is lower than 283 ml/min/m2 in 97.5% of patients. Finally, arterial vasoconstriction does not seem to play a significant role in tissue hypoperfusion.
Clinical outcome after coronary surgery with heparin-coated extracorporeal circuits for cardiopulmonary bypass
Authors: Baufreton Christophe , Le Besnerais Paul , Jansen Piet , Mazzucotelli Jean Philippe , Wildevuur Charles RH , Loisance Daniel Y 
Published: November 2007

In this prospective randomized trial, we studied whether heparin-coated extracorporeal circuits (ECC), known to reduce complement activation, could improve the clinical outcome of 200 patients undergoing coronary artery surgery. Patients have been divided into two groups (heparin-coated ECC and uncoated ECC groups) which were similar in terms of age, gender, left ventricle function, preoperative aspirin use and consequent intraoperative aprotinin use, number of grafts, duration of aortic cross-clamping and cardiopulmonary bypass. Univariate analysis showed that heparin coating did not reduce significantly postoperative bleeding (640 ± 311 versus 682 ± 342 ml with uncoated ECC) nor the need for transfusion (19% of patients versus 25% with uncoated ECC). Adverse events, including all mortality and morbidity noticed during the five first postoperative days, occurred in 20 patients of the uncoated ECC group and in eight patients of the heparin-coated ECC group (p = 0.013). The most frequent complications were supraventricular arrhythmias that occurred in 13 patients of the uncoated ECC group and in four patients of the heparin-coated ECC group (p = 0.02). Multivariate analysis by stepwise logistic regression showed that only heparin coating of the ECC was shown as a significant predictive factor of adverse events reduction (p = 0.01; odds ratio = 0.34). These data suggest that heparin coating reduced postoperative complications in patients undergoing coronary artery surgery.
Problems of terminal care in elderly patients
Authors: Blackburn AM 
Published: November 2007

The care given to 27 elderly men dying in a geriatric ward was examined and compared with terminal care directed to younger patients dying with cancer. Important practical differences were highlighted: 1) Difficulties in communication with elderly dying patients are frequently encountered and require heightened powers of observation of nonverbal information and empathy. 2) There is often little time for staff to provide effective terminal care for elderly patients. The diagnosis of dying is frequently made by exclusion, after failure of standard medical treatment. It is more difficult in the absence of neoplasia and requires a more holistic approach to patient care. 3) A significant proportion of elderly patients who die in hospital do not have family or friends to visit them and may require additional attention and support.
Sodium naproxen: continuous subcutaneous infusion in neoplastic pain control
Authors: Toscani Franco , Barosi Katia , Scazzina Maurizio , Camerini Sandro 
Published: November 2007

Fourteen patients who had been taking naproxen orally (as a single analgesic or in association with morphine, according to the therapeutic drug sequence proposed by WHO) were changed to a subcutaneous continuous infusion of sodium naproxen alone (10 cases) or associated with morphine (4 cases), administered via a portable micro-pump because of the impossibility of taking it orally. All the patients had pain from advanced cancer. The patients were all monitored with daily checks on the severity and duration of pain, numbers of hours slept, drug use and symptom appearance. Follow-up was continued until death. The same level of analgesia achieved by oral administration was maintained for all patients. In two cases, the presence of a high sodium naproxen and morphine concentration in the same syringe produced a precipitate of morphine which caused an obstruction of the butterfly needle. The administration of sodium naproxen not combined with other drugs in the pump proved a valuable technique, well accepted by the subjects. Its effectiveness appears comparable to oral administration of naproxen.