bluuebunny/crossref_metadata_2025 huggingface dataset:
Universal Grammar and the acquisition of French verb movement by native speakers of English
Authors: Hawkins Roger , Towell Richard , Bazergui Nives
Published: November 2007

White (1989) has shown that L1 English-speaking learners of L2 French appear to be more successful in acquiring the postverbal location of French manner and frequency adverbs than L1 French-speaking learners of L2 English are in acquiring the preverbal location of English manner and frequency adverbs. One implication of recent work by Pollock (1989) on the structure of English and French clauses is, however, that the task of acquiring the placement of manner and frequency adverbs should be the same for both sets of learners, because English provides learners with as much positive syntactic evidence for preverbal manner/frequency adverbs as French does for the postverbal location of such adverbs. The problem, then, is to explain why there should be this difference in success. On the basis of a detailed study of the developing intuitions of English-speaking adult learners of L2 French it is suggested in this article that the English-speakers' success is only apparent. Both groups of learners have great difficulty in resetting a parametrized property of the functional category Agr, but the English- speaking learners of French are able to make use of nonparametrized properties of Universal Grammar to handle surface syntactic differences between English and French, properties which are not so readily available to the French-speaking learners of English. It is suggested that this finding is in line with an emerging view about the role of parametrized functional categories in second language acquisition.
The ins and outs of paragoge and apocope in Japanese-English interphonology
Authors: Ross Steven
Published: November 2007

Syllable structure in interphonology has consistently demarcated the initial phases of phonological transfer, as well as the basis for a putative universal preference for the open syllable. The manner in which syllable structure is continually reorganized during the processes of acquisition has, however, not attracted much attention. This article addresses two phenomena in the acquisition of second language syllable structure - a preference for open syllables, as manifest in paragoge, and a developmental process of final segment apocopation that applies to first language lexical items appearing under the domain of the second language intonational envelope. The data for the analyses come from spontaneous utterances produced by Japanese students of English as a foreign language. Results of two ten-factor variable-rule analyses suggest that paragogic epenthesis is conditioned by a syllable structure constraint based on the L1, and that variation in the type of segment epenthesized is governed by natural phonological constraints. Analyses of the apocope dataset indicate that acquisition of L2 stress patterns leads to a restructuring of the syllable structure constraint leading to suppression of open syllables in the L2.
The preference for Modal + Neg: an L2 perspective applied to Swedish L1 children
Authors: Hakansson Gisela , Collberg Sheila Dooley
Published: November 2007

Universal Grammar (UG), as it is conceived in the current principles and parameters approach to grammatical theory, may be said to contain certain default parameter values which are already in place at birth. If this is the case, then any languages which eventually show marked parameter values will necessarily involve a change in parameter settings during the L1 acquisition sequence. An indication of such a change can be signalled by a pattern of late acquisition of some feature. We will here argue that the correct placement of sentential negation with respect to modal auxiliaries in Swedish is such an example of delayed acquisition due to a parametric preference in UG. A syntactic analysis will be proposed for the four recognized stages in the acquisition of negative word order in Swedish which supports the view that a change must occur in the learner's analysis of modal auxiliaries before the last stage has been reached.
Interpretation of English reflexives by adolescent speakers of Serbo-Croatian
Authors: Bennett Susan
Published: November 2007

This article addresses the question of L1 transfer in L2 acquisition of reflexive binding. It incorporates recent research on Binding Theory which focuses on the relationship between morphological complexity of anaphors and the occurrence of long-distance binding of reflexives (cf. Yang, 1983; Pica, 1987; Hellan, 1988; Battistella, 1989; Huang and Tang, 1989; Cole et al., 1990; Progovac, 1992). Reflexives typically fall into two categories: simple (X0) reflexives that may take long-distance antecedents and complex (XP) refle xives that may not. Acquisition of the English binding pattern by native speakers of Serbo-Croatian requires recognition of the morphological com plexity of English reflexives. Prior to reanalysis, learners are predicted to transfer the L1 X0 anaphor type and incorrectly assign long-distance antece dents to English XP reflexives.

The interpretation of English reflexives by native speakers of Serbo- Croatian was investigated using two types of written sentence comprehension tasks. A picture identification task and a multiple-choice questionnaire were administered to intermediate ( n = 20) and advanced (n = 20) L2 learners and a group of English native speaker controls (n = 20). Results consistent across task type support the transfer hypothesis and suggest learners have access to Universal Grammar in second language acquisition.
Agreement and null subjects in German L2 development: new evidence from reaction-time experiments
Authors: Clahsen Harald , Hong Upyong
Published: November 2007

In L1 acquisition research, developmental correlations between superfi cially unrelated linguistic phenomena are analysed in terms of clustering effects, resulting from the setting of a particular parameter of Universal Grammar (UG). In German L1 acquisition, there is evidence for a cluster ing of the acquisition of subject-verb agreement and the decrease of (incor rect) null subjects. The developmental connection between these two phenomena in L1 acquisition has been interpreted in terms of parameter setting. Vainikka and Young-Scholten (1994) have claimed that the acqui sition of subject-verb agreement and non-pro-drop in adult L2 learners developmentally coincides in the same way as it does in child L1 learners. This is taken to indicate that UG parameters are fully accessible to adult L2 learners. In this article we will report on reaction-time (RT) experi ments investigating subject-verb agreement and null subjects in 33 Korean learners of German and a control group of 20 German native speakers. Our main finding is that the two phenomena do not covary in the Korean learners indicating that (contra Vainikka and Young-Scholten) properties of agreement and null subjects are acquired separately from one another, rather than through parameter resetting.
Acquisition of pronominal reference: a longitudinal perspective
Authors: Broeder Peter
Published: November 2007

This article is based on a large corpus of data collected as part of the European Science Foundation Project on Second Language Acquisition by Adult Immigrants (Perdue, 1984; 1993). In this study, some empirical observations are discussed from a follow-up on the ESF project. This follow-up study dealt with the conceptual domain of people (Broeder, 1991; 1992). Mostly, the encoding of reference to people is done through nouns and pronouns. Nominal reference involves a set of proper names and more or less complex noun phrases (e.g. Ahmet, my brother, my neighbour's sister). Pronominal reference is based on an exhaustive list of frequently used and predominantly monosyllabic words (e.g., I, you, he, etc.). Learners necessarily have to use a restricted set of nouns and pronouns as efficiently as possible in daily interactions with native speakers. This study examines the acquistion of pronouns. The relevant questions are: how do people start our encoding pronominal reference, how does their repertoire of pronouns develop and why do they make the choices they make?
Interaction between linguistic theory and language processing in SLA
Authors: Myles Florence
Published: November 2007

This article examines L2 performance in three areas of French morphosyntax by English L1 learners. More particularly, it examines how coindexation as defined within the government-binding framework develops in the L2 grammar. Empirical studies relating the development of two areas of French grammar by English L1 speakers are presented. L2 performance on information questions involving qui and que in which learners have to link the wh-phrase and its trace in order to establish the syntactic function of the wh-phrase in the sentence is examined, as well as performance on the morphological phenomenon of noun-adjective agreement in French where learners have to transmit agreement features from a noun to an adjective which it governs. In both cases, learners are found to increase gradually the structural domain in which they are able to operate as their level of competence in the L2 improves, suggesting that they are faced with a parsing problem when coindexing elements in a sentence. These findings are related to a study of the acquisition of restrictive relative clauses in French L2 by English learners (Hawkins, 1989), and then discussed in the light of the current debate in SLA research about the roles played by linguistic theory, on the one hand, and language processing mechanisms on the other.
The early stages in adult L2 syntax: additional evidence from Romance speakers
Authors: Vainikka Anne , Young-Scholten Martha
Published: November 2007

Vainikka and Young-Scholten (1994) propose an analysis of the acquisition of German by adult Korean and Turkish speakers based on the Weak Continuity account of L1 acquisition. They claim that L2 acquisition initially involves a bare VP whose (final) headedness is transferred from the learner's L1, with functional projections evolving entirely on the basis of the interaction of X'- Theory with the input. In this article, we extend this account to data from Italian and Spanish speakers learning German. Our analysis reveals that these learners initially posit a bare VP whose (initial) headedness is transferred from their native languages but, while still at the bare VP stage, they adopt the head-final VP of German. At this bare VP stage the morphological elements incompatible with the VP are not attested (e.g., auxiliary verbs, verbs marked for agreement and obligatory subjects). At the next stage of acquisition, simi lar to what Vainikka and Young-Scholten observed for the Korean and Turkish speakers, the Italian and Spanish speakers posit a head-initial func tional projection. This projection further resembles the first functional projec tion observed in the acquisition of German by children (Clahsen, 1991) and involves optional verb-raising and the emergence of elements which typically appear in INFL (auxiliaries, modals) and in Spec (IP) (obligatory subjects). We conclude that child L1 learners and adult L2 learners build up syntactic structure in much the same manner and propose that the Weak Continuity approach accounts for all instances of syntactic acquisition.
Cephradine and cefazolin plasma levels during cardiac surgery
Authors: Moran Sergio V , Montiel Francisco , Acuña Guillermo , Vergara Jeanette , Irarrazaval Manuel J , Maturana Gustavo , Dubernet Juan
Published: November 2007

A prospective, randomized, double-blind study was carried out to evaluate two prophylactic regimes in patients undergoing cardiac surgery with cardiopulmonary bypass. Antibiotic plasma levels were measured in fifty consecutive adult patients undergoing valve and coronary surgery. They were divided into two comparable groups of 25 patients, each matched in age, sex, type of operation and duration of cardiopulmonary bypass. Group 1 received 1 g of cephradine with the anaesthetic premedication, 1 g in the prime of the oxygenator and 1 g every six hours during the first 72 hours of the postoperative course. Group 2 received cefazolin following the same protocol except that they received 1 g every eight hours during the postoperative course.

There were no allergic or toxic reactions and no infections up to two months follow-up in both groups. Antibiotic plasma levels were significantly higher (p < 0·001) in the cefazolin group in four out of five sampling periods. Antibiotic plasma levels for group 1 versus group 2 were as follows: initial level 11·7 ± 5.2 mcg/ml vs 31 4 ± 35·4 mcg/ml. During cardiopulmonary bypass 26·6 ± 9·5 mcg/ml vs 51·7 ± 21 ·1 mcg/ml. Final levels 13·6 ± 7·0 mcg/ml vs 32·2 ± 17·8 mcg/ml. Baseline levels 2·7 ± 2·3 mcg/ml vs 6·· ± 7·7 mcg/ml and peak level 44·0 ± 16·2 mcg/ml vs 51·2 ± 23·4 mcg/ml (NS). The results of this study demonstrate that cefazolin achieved significantly higher plasma levels during the different phases of the operation and early postoperative period. Also, cefazolin and cephradine levels are above the minimal inhibitory concentrations for the gram positive and gram negative susceptible bacteria, except for the basal levels obtained by cephradine. The favourable pharmacokinetic characteristics of cefazolin, makes it a good choice for prophylactic use during cardiac surgery.
Reversal of protamine reaction with heparin
Authors: Utley Joe R , Bhatt Manoj A , Stephens D. Barton , Kelley Henry G
Published: November 2007

We recently encountered a patient who had severe cardiovascular collapse following administration of protamine. This severe protamine reaction was resistant to all forms of pharmacological therapy except for heparinization. Heparinization resulted in immediate reversal of the cardiovascular collapse.
A clinical evaluation of the performance characteristics of one membrane and five bubble oxygenators: haemocompatibility studies
Authors: Pearson Derek T , McArdle Brian , Poslad Stefan J , Murray Alan
Published: November 2007

The haemocompatibility of five different bubble oxygenators (Polystan venotherm, Harvey H-1700, Bentley BIO-10, Gambro 10 and Shiley S-100A HED) and one membrane oxygenator (Cobe CML) have been evaluated during standardized clinical perfusion for open-heart surgery in 48 adult patients. Control of arterial PO2 and PCO2 was an important feature of the evaluation protocol. Over the period of cardiopulmonary bypass (CPB) there was a marked difference in the mean percentage reduction in platelet count in the different oxygenator groups. Only 1% reduction in platelet count occurred with the Cobe CML membrane oxygenator group compared with, in the bubble oxygenator groups, 7% for the Gambro 10, 16% for the Harvey H-1700, 19% for the Shiley S-100A HED, 24% for the Bentley BIO-10 and 31% for the Polystan venotherm. The post bypass platelet count was significantly lower than the prebypass value in all oxygenator groups ( p < 0.05) except the Cobe CML and Gambro 10. The two oxygenator groups with the largest percentage reduction in platelet count (Polystan venotherm and Bentley BIO-1 0) demonstrated a significant reduction ( p < 0.05) in platelet aggregation over the period of bypass. Platelet depletion in the Harvey H-1700. Shiley S-100A HED, Bentley BIO-10 and Polystan venotherm oxygenators was associated with a significant fall ( p < 0.05) in mean platelet volume during the first 35 minutes of CPB due to the removal from the circulation of large, young, functionally more active platelets. Erythrocyte damage was minimal in all oxygenator groups and only a minor degree of leucopenia could be demonstrated during the first five minutes of CPB. Cardiotomy suction was not associated with significant changes in platelet numbers or platelet aggregation. When selecting the oxygenator for use in patients undergoing open-heart surgery, gas transfer characteristics and GME production together with the superior preservation of platelet numbers and function in the membrane oxygenator group and variable degree of platelet depletion and reduction in platelet aggregability demonstrated in the five bubble oxygenator groups, must be taken into account.
Use of low molecular weight heparin CY 222 during cardiopulmonary bypass. Experimental study and clinical application
Authors: Touchot B. , Laborde F. , Dum F. , Commin P. , Gallix P. , Mirshahi M. , Piwnica A.
Published: November 2007

Cardiopulmonary bypass (CPB) standard heparin and protamine therapy is a relatively satisfactory part of conventional CPB practice. However, some problems are known to result from both heparin and protamine sulphate administration. These include: allergic reaction and thrombocytopenia due to heparin, and anaphylactoid reactions, negative inotropic effects, pulmonary oedema and pulmonary hypertension due to protamine administration.

Low molecular weight heparin (LMWH) should theoretically be superior decreasing the adverse effects of standard heparin. In addition, it should not require the use of protamine for heparin neutralization.

These potential benefits of LMWH encourage the experimental evaluation of the use of LMWH during open-heart surgery before preliminary clinical applications.
Transfusional quality of residual blood from heart—lung machine after extracorporeal circulation
Authors: Berty A. , Doutremepuich Ch , Baudet E.
Published: November 2007

After open-heart surgery using extracorporeal circulation, residual blood from the heart-lung machine was collected, treated by plasmaphaeresis and washed using a Haemonetics Cell Saver. Qualitative, quantitative and bacteriological aspects of the concentrated red cells were studied.

In 13 patients, an average of 500 ml of concentrated washed red cells (CWRC) was obtained with an average haematocrit of 62·3 %; bacteriological cultures were negative in all cases. As far as qualitative aspects were concerned (intraglobular ATP, 2, 3 DPG, deformability, filtrability and resistance to hypotonic solutions), these red cells were always compatible with immediate transfusion. However, the small volume of blood retrieved and the relatively high cost of this technique suggest that its use be restricted to cases of total haemodilution or for patients with rare blood groups, in whom homologous transfusion blood is scarce.
The prevention of trapped air within ventricular assist devices during connection to the circulation
Authors: Cooper Len , Glenville Brian , Roehm Karla , Ross Donald N.
Published: November 2007

One of the major concerns when implanting a ventricular assist device (VAD) is the total exclusion of air which is potentially dangerous to the patient. We found in our early experience with VADs that the complete removal of air during connection proved difficult. We have developed a simple and effective method of priming the VADs and removing air. The method relies upon the relative solubilities in blood of C02 and air.
Compartment syndrome as a complication of intra-aortic balloon pumping
Authors: Crockett JR , Glenville B. , Bennett JG
Published: November 2007

Intra-aortic balloon pumping (IABP) is a well accepted therapy in low cardiac output states. The complications reported with the use of IABP are varied. Development of a swollen, tender calf and loss of sensation and/or function, yet retaining a warm limb with the palpable peripheral pulses during or immediately after IABP is one such complication. We believe that this represents compartment syndrome following temporary or partial ischaemia. We set out to measure the compartment pressure in 13 patients in whom IABP was used following coronary artery bypass graft surgery. Our results show that the slit catheter method used in this study to measure compartment pressures gave reliable results, was easy to set up and use and provided early warning of compartment syndrome, thus facilitating early treatment and viability of all limbs affected.
The effect of autologous blood salvage techniques upon bank blood usage and the cost of routine coronary revascularization
Authors: Hiratzka Loren F , Richardson James V , Brandt Berkeley , Doty Donald B , Rossi Nicholas P , Wright Creighton B , Ehrenhaft JL
Published: November 2007

Preservation of autologous blood during cardiac surgery may reduce the need for homologous blood transfusions. We reviewed our experience for patients undergoing primary coronary revascularization to determine the effect of the use of the Haemonetics Cell-Saver upon blood bank resources and upon the cost of operation.

The quantity of homologous blood required by two groups of patients was compared. One group of 46 patients had operation prior to use of the Cell- Saver ; the other group of 31 patients was entered into Cell-Saver protocols. The mean number of homologous blood units transfused per patient fell strikingly (p < 0.0001) from 4.2 before to 0.5 after introduction of the Cell- Saver. Of the 31 patients in the Cell-Saver protocol, 71 % required no homologous blood while they received 2.5 units of autologous blood processed by the Cell-Saver. Related to this, the mean number of units prepared by typing and compatibility testing in anticipation of surgery fell from 10 units to five. The projected cost to the patient fell 23%. There were no adverse effects from the use of the Cell-Saver.

We conclude that the use of the Cell-Saver is justified not only to reduce the potential risks of homologous blood transfusion, but also to reduce the strain upon blood bank resources and the patient cost of primary coronary revascularization.
The effect of normothermic cardiopulmonary bypass on hepatic blood flow in the dog
Authors: Mathie RT , Desai JB , Taylor KM
Published: November 2007

Hepatic blood flow was investigated in two groups of eight anaesthetized dogs during and after one hour of either pulsatile or non-pulsatile cardiopulmonary bypass (CPB). Mean perfusion pressure was maintained at 60 mmHg. Hepatic arterial (HA) and portal venous (PV) blood flows were measured using electromagnetic flow probes, and hepatic O 2 consumption determined. The results demonstrate that: (a) pulsatile CPB reduces peripheral vascular resistance during and after perfusion, and more effectively preserves pump flow rate and cardiac output than non-pulsatile CPB; (b) total liver blood flow is sustained more effectively by pulsatile CPB than by non-pulsatile CPB due to relative preservation of both HA and PV flows; (c) hepatic O2 consumption is only marginally better preserved during and after pulsatile CPB than with non-pulsatile perfusion. We conclude that: (a) pulsatile CPB tends to maintain hepatic blood flow through a relative reduction in HA vascular resistance and an improvement in PV flow produced passively by a greater pump flow rate; (b) pulsatile CPB less effectively benefits hepatic O2 consumption because of poor O2 uptake from the hepatic PV blood supply.
Inflight use of extracorporeal membrane oxygenation for severe neonatal respiratory failure
Authors: Cornish J. Devn , Gerstmann Dale R , Begnaud Martin J , Null Donald M , Ackerman Neil B
Published: November 2007

Extracorporeal membrane oxygenation (ECMO) is a heart-lung bypass technique which has been used over the past ten years to support some 300 neonates with life-threatening respiratory failure. It is estimated that, within the constraints of currently accepted treatment criteria, there are between 2,000 and 3,000 neonates born each year within the United States who require this extreme therapeutic measure. Unfortunately, since there are still relatively few medical centres in the country offering this type of support, it is frequently necessary to transport candidate neonates from the hospital of birth to a referral centre. This is generally a tenuous procedure since neonates who are sufficiently ill to require ECMO treatment are commonly poor transport risks. We report the first successful use of an ECMO system designed to be transported to the referring hospital, assembled, and used to support an infant on bypass for a controlled air transport back to the receiving medical centre. The potential for decreasing the morbidity and mortality of selected infants requiring ECMO support by the addition of this capability is discussed.
A low prime extracorporeal system for small patients: a primate model
Authors: Wheeldon D. , Bethune D.
Published: November 2007

In the course of developing a technique for heart and lung transplantation a 6 kg Rhesus monkey model was used. We required a low prime circuit, because it was difficult to obtain donor blood for these animals, which was also capable of supporting the circulation for up to two hours. We describe a system incorporating a semidisposable bubble oxygenator, run under controlled negative pressure with very short blood lines. This arrangement allows for a priming volume of 110 ml with good venous drainage control. The principle could be exploited for use with paediatric extracorporeal systems.
Isolated limb perfusion for regional chemotherapy
Authors: Ashcroft P. , Bell J.
Published: November 2007

The use of hyperthermic isolated limb perfusion in conjunction with antiblastic drugs is finding ever wider applications in the treatment of malignancies localised in the extremities. The basic technique was described nearly 30 years ago,' but recent refinements in surgical technique, perfusion and cytotoxic therapy have brought about very encouraging results. The technique described outlines particular considerations with respect to effective limb isolation, temperature control, perfusion control and measures required to limit the systemic toxic side effects of the drugs used.
The Variable Prime Cobe Membrane Lung: first impressions
Authors: Crockett JR , Grey PA
Published: November 2007

The Variable Prime Cobe Membrane Lung (VPCM L) is intended to be used as a variable membrane package: any one of three combinations of membrane surface areas can be used, depending on the patient's requirements. We used all three membrane configurations and determined their performance with regard to gas transfer, haemodilution, blood trauma, pressure gradient and flow distribution. In addition, the ability of the VPCML to achieve a consistent level of blood gas control was studied. Heat exchanger performance was also assessed.
Computerised techniques for detecting gaseous microemboli in blood using pulsed Doppler ultrasound
Authors: Padayachee TS , Parsons S. , Theobold R. , Kontis S. , Gosling RG , Linley J.
Published: November 2007

Pulsed Doppler ultrasound and spectral analysis were used to monitor nonpulsatile blood flow generated in a test rig. Two computerised techniques are described for detecting microemboli in blood by analysis of Doppler blood velocity data (sonagram).

The two ultrasound microemboli indices identify different features in the ultrasound signals to detect microembolic phenomena. Both indices showed significant increases ( p < 0.001) for samples of agitated blood (containing gaseous microemboli) as compared to normal blood injected sequentially into the test rig. The linear relationship demonstrated between data obtained by the two methods ( r = 0.91, p < 0.01) indicates that both are providing similar quantitative information regarding the number of microemboli detected.

These two computerised techniques may be applied to sonagrams obtained from arterial blood flow and thereby provide information regarding the presence of gaseous microemboli in the circulation during cardiopulmonary bypass surgery.
Determination of significant differences in performance of the Bentley BOS-CM 40 hollow fibre membrane oxygenator and the Polystan VT5000 venotherm bubble oxygenator
Authors: von Segesser Ludwig
Published: November 2007

Ten mongrel dogs were connected to cardiopulmonary bypass by cavoaortic cannulation, classic roller pump and either Bentley BOS-CM 40 hollow fibre membrane oxygenator or Polystan VT5000 Venotherm bubble oxygenator for eight hours, with mean flow rate of 100 ml/kg min. Platelet counts (all values corrected by prebypass haematocrit) were significantly lower in the bubble oxygenator group after two hours of cardiopulmonary bypass (p < 0·01). Plasma haemoglobin production was significantly higher after two hours of cardiopulmonary bypass in the bubble oxygenator group (p < 0·01). Venous oxygen saturation (SvO2) was above 65% during the eight hours perfusion in the membrane oxygenator group. In the bubble oxygenator group, however, SvO2 was below 60% after six hours of cardiopulmonary bypass. After eight hours perfusion the difference in SvO2 between the two groups was significant (p < 0·05). Thus membrane oxygenators such as the Bentley BOS-CM 40 appear to be indicated in cardiopulmonary bypass of more than two hours duration.
Placebo-controlled study of Iloprost (ZK 36374) in cardiopulmonary bypass surgery
Authors: Spyt TJ , Wheatley DJ , Walker ID , Davidson JF , MacArthur Kjd , Martin W.
Published: November 2007

The effects of infusion of Iloprost (ZK 36374), a prostacyclin analogue, on platelet function, postoperative blood loss and microaggregate deposition on filters and oxygenators were studied in patients undergoing routine coronary operations. In this double-blind randomized study of 50 male patients, 25 received Iloprost and 25 a placebo. Platelet deposition was assessed using Indium-labelled platelets. Comparison of Iloprost and placebo groups showed the mean number of platelets to be significantly higher in the Iloprost group at the end of cardiopulmonary bypass and in early postoperative recovery. Similarly, spontaneous aggregation of platelets was higher in the placebo group. The mean percentages of platelets sequestrated in the extracorporeal circuit were significantly higher in the placebo group. There was no difference in either the amount or pattern of postbypass bleeding between Iloprost and the control patients. Infusion of the tested drug was responsible for significant hypotension, which was correctable with fluid administration alone. Thus, Iloprost diminishes the fall in circulatory platelet count during cardiopulmonary bypass, preserves platelet function, diminishes platelet deposition on filters and oxygenators, but also causes arterial hypotension.
Transcapillary forces of the subcutaneous tissue in patients with coronary artery disease: a comparison between pulsatile and nonpulsatile flow during extracorporeal circulation
Authors: Rein Kjell A , Aune Dagfinn , Levang Olaf W , Stenseth Roar , Myhre Hans O
Published: November 2007

The aim of this study was to evaluate subcutaneous transcapillary fluid balance during pulsatile and nonpulsatile extracorporeal circulation (ECC). Changes in the transcapillary fluid balance were studied by measuring subcutaneous interstitial fluid pressure (Pif) using the 'wick in needle' (WIN) method, as well as measuring subcutaneous interstitial fluid colloid osmotic pressure (COPif), using either the wick technique or the blister suction technique. The measurements were performed on the chest wall at the heart level. Simultaneous recordings of plasma colloid osmotic pressure (COPpl) were carried out. Nineteen male patients undergoing aortocoronary bypass grafting were subjected to nonpulsatile flow (group I, n = 11) or pulsatile flow (group II, n = 8) during ECC. Preoperatively there was no difference in the Starling forces between the two groups. During ECC the COP gradient (COPpl-COP if) was reversed to the same extent in the two groups. At three hours and six hours following ECC, COPif in the pulsatile group (12.1 mmHg and 11.4mmHg respectively) was significantly higher than in the nonpulsatile group (10.8mmHg and 10.3mmHg respectively). When weaning from ECC as well as three hours and six hours following ECC, Pif in the pulsatile group was significantly lower than in the nonpulsatile group. Conclusion: in the early postoperative period there is less dilution of the subcutaneous interstitial tissue following application of pulsatile flow during ECC compared to nonpulsatile flow.
A clinical evaluation of a monitor for inline measurement of pO2, pCO2 and pH during cardiopulmonary bypass
Authors: Alston R Peter
Published: November 2007

The Gas STAT is a monitor which continuously measures pO2, pCO2 and pH inline during cardiopulmonary bypass. A clinical evaluation of the inline monitor compared to the standard method of monitoring, that is, intermittent isolated blood sampling and distant measurement on a blood gas analyser (BGA), was undertaken. During stable moderate hypothermia, 115 paired measurements were made in 54 patients undergoing coronary artery or heart valve surgery. The correlations between pO2, pCO2 and pH, as measured by the BGA and the inline monitor, were respectively 0.536 ( P<0.001), 0.811 ( P<0.001) and 0.826 ( P<0-001). pCO2 as measured by the inline monitor was significantly lower than the BGA ( P<0.001 ) whereas pH was significantly higher ( P<0.001). There was no significant difference between pO2 measurements. Possible explanations for the finding of less than complete correlations are discussed and it is suggested that although inline monitoring is of value in the control of PO2, pCO2 and pH during cardiopulmonary bypass, it should not be used without recourse to the standard method of blood gas analysis.
Automatic data collection for cardiopulmonary bypass
Authors: Berg E. , Knudsen N.
Published: November 2007

An open software system for automatic data collection during cardiopulmonary bypass is presented. The software is run on a microprocessor with permanent memory, a general purpose interface board capable of analogue-to-digital conversion and five serial communication ports for data collection.

Analogue data signals for blood flow, gas flow, patient temperatures and pressures are automatically recorded and referenced to real time. Continuous inline blood gas and temperature parameters are passed to the microprocessor for storage in a database. Results from a blood analyser and an electrolyte analyser, placed in the next room, are automatically passed to the computer and presented on the screen.

This system provides the perfusionist with automatic preoperative calculations of all parameters necessary for setting up the perfusion. During bypass, data are automatically collected, presented for evaluation and used in calculated transformations. A maximum of 36 real time curves are traced and stored as trend curves. In critical situations they may also be stored as real time curves. These curves can be recalled or plotted for further analysis. At the end of bypass a perfusion report is printed out.

The records of the patients are permanently stored on disk and the files can be transferred to other software systems for further statistical analysis.
Prolonged cardiopulmonary bypass in patients requiring extensive coronary endarterectomy and reconstruction
Authors: Harloff M.
Published: November 2007

The technique of coronary endarterectomy and reconstruction is a tedious and time-consuming surgical procedure. A 14cm endarterectomy may be required fora diffusely diseased artery, such as the left anterior descending coronary artery. With accompanying diagonal branches and septal perforators requiring reconstruction, this single vessel procedure may require as long as 90-115 minutes of aortic crossclamp time.

Multiple endarterectomies, including the marginal branches of the circumflex system as well as multiple branches of the right coronary system, may consume an additional 100-125 minutes of aortic crossclamp time. In our experience, it is not uncommon for total aortic crossclamp time to exceed 200 minutes. Because of the totally occlusive nature of the coronary atheromatous disease, cardioplegia is impossible to deliver. As a result, the method of intermittent ischaemic arrest has proven, in our experience, to be the technique of choice for myocardial preservation.

It has become necessary to develop a perfusion protocol which vvill support a surgical procedure which may require a total of 300 to 420 minutes on cardiopulmonary bypass (CPB).
Perioperative cha nges of seru m CPK, CPK-MB and LDH levels in patients undergoing open-heart surgery
Authors: Youcai He  , Liye Hou  , Cheng Cai Xian
Published: November 2007

The effects of aortic crossclamp time, myocardial incision size and location, bypass time and hypothermia were investigated with respect to perioperative enzyme changes; CPK, CPK-MB and LDH, in 40 patients undergoing a variety of open-heart procedures for acquired and congenital heart disease. This study indicates that, with the exception of CPK-MB, these enzyme levels returned to normal by the seventh postoperative day and that there are significant differences in elevations relative to crossclamp time, size and location of the myocardial incision, but not to bypass time or hypothermia.
A new multipurpose aortic root cannula for open-heart surgery
Authors: Fundaro Pino , Velardi Antonio R , Cilley Jonathan H , Vertrees Roger , Del Rossi Anthony J , Di Biasi Pietro , Santoli Carmine
Published: November 2007

Cold cardioplegic infusion is widely and successfully used today for myocardial protection. Cardioplegic solution is administered using a variety of means and techniques. This paper introduces a newly developed double-lumen cannula that allows the delivery of cardioplegic solution via the aortic root with simultaneous air aspiration, thus preventing coronary artery embolization. The featured double- lumen is useful for the removal of air from the aortic root after the releasing of the aortic cross-clamp. This aortic cannula also features an additional port that provides monitoring of the infusion pressure in the aortic root. This cannula has been used safely, effectively and without complications in 200 cases and we think it is a valid aid in open-heart surgery.
A computerized system forthe study of oxygen uptake and haemodynamics during cardiopulmonary bypass
Authors: Alston RP , Rennie RA , Toal F. , Kenny Gnc
Published: November 2007

A computerized system which incorporated haemodynamic, temperature and arterial pH (pHa) monitoring was developed to record data and to improve temperature and pHa control during hypothermic cardiopulmonary bypass (CPB). The system was evaluated in the course of a study of haemodynamics and metabolism during CPB. It was planned to have three 10 minute periods of study in 24 patients, during which time arterial and nasopharyngeal temperatures would be maintained between 27° and 29°C and pHa between 7.38 and 7.42. Repeated recordings of haemodynamic variables, temperature and pHa were made during each period. Only 59 of a possible 72 periods were obtained due to shortage of time at stable hypothermia. The mean number of total readings was 73.5 (70.1, 77.0) and the mean number of acceptable readings was 71.2 (67.3, 75.1). Good nasopharyngeal temperature control was achieved, with all the 95% confidence intervals of the means falling within the prescribed limits. Control of arterial temperature was less good as there were five periods in which the 95% confidence intervals of the means fell outwith the prescribed range. Poor pHa control was achieved since there were 16 periods in which the 95% confidence intervals of the mean were outside the preset range. The system functioned well in recording data and resulted in good temperature control, but poor pHa control.
Correlates of blood volume, red cell mass and plasma volume in coronary bypass patients
Authors: Utley Joe R , Morgan MS , Johnson Howard D , Wilde Connie M , Bell Michael S
Published: November 2007

Prebypass blood volume (BV), red cell volume (RBC) and plasma volume (PV) may affect haematocrit during and after cardiopulmonary bypass (CPB), volume shift in and out of the oxygenator during CPB and the need for blood transfusion. We have calculated BV, RBC, and PV in 1076 patients having coronary artery bypass (CABG). Multiple regression analysis was performed to determine the preoperative factors which correlated with BV, RBC and PV. BV was found to correlate significantly with body surface area (BSA), sex, ejection fraction and emergency operation. RBC correlated significantly with sex, smoking, weight, emergency operation and obesity (body mass index). Significant correlations were found between PV and BSA, ejection fraction, emergency operation and sex. Body size (BSA and weight) is a major determinant of BV, RBC and PV in coronary artery surgery patients. Female patients have significantly diminished BV, RBC and PV, the decrease is greatest for RBC. Equal increases in BV and PV are associated with decreased ejection fraction. Emergency operation is correlated with increases in BV, RBC and PV. RBC is increased in smokers and the obese (BMI).
Experimental evaluation of the Dideco Masterflo paediatric hollow-fibre membrane oxygenator
Authors: von Segesser L. , Leskosek B. , Redha F. , Garcia E. , Turina M.
Published: November 2007

Nine mongrel dogs (mean bodyweight: 29 ± 6kg) were connected to cardiopulmonary bypass byfemorojugularvenous and femoral arterial cannulation, classic roller pump and the integrated Dideco D702 Masterflo hollow-fibre membrane oxygenatorwith a mean flow rate of 70ml/kg/min for six hours. Then the animals were weaned from cardiopulmonary bypass and thereafter weaned from the ventilator. After seven days all animals were sacrificed electively for necropsy. A standard battery of blood samples was taken before the bypass, after mixing (10 minutes), after two hours, five hours and six hours of perfusion. Further samples were taken 30 minutes after bypass (spontaneous breathing), 60 minutes after bypass (after extubation), 24 hours after bypass, 48 hours after bypass and seven days after bypass. Physiologic blood gas values could be maintained throughout perfusion in all animals. Mean arterial oxygen saturation varied between 99.7% and 99.9% for the arterial side of the oxygenator compared to 77.8% and 86.6% on the venous side. Post bypass blood gas analyses showed physiologic values and no evidence of major lung trauma or pulmonary oedema in relation to the six hours' bypass. Red blood count was 5.84 ± 0.02 before and 4.63 + 0.1 million/mm3 after mixing and dropped to 3.89 ± 0.52 till the end of the bypass. After seven days the red blood count was practically normalized with over 5,000,000 erythrocytes per mm3 at the end of the observation. Blood trauma evaluated in function of plasma haemoglobin and (thrombocyte) depletion showed the following results: prebypass: 2.3 ± 0.7 μmol/l plasma haemoglobin and (220 ± 24 thousand thrombocytes per mm3); after six hours perfusion: 26.2 ± 15.5 and (137 ± 12); after seven days: 9.3 ± 4.1 and (400 ± 125). Post mortem studies did not demonstrate any deleterious lesions.
Current priming solutions for cardiopulmonary bypass contain a potent coronary vasodilator
Authors: Tamari Yehuda , Tortolani Anthony J , Maguine Melanie , Czegledy Ferenc
Published: November 2007

We studied the effects of acetate (Ac), the buffer in crystalloids used during cardiopulmonary bypass (CPB) (e.g. Normosol-R and Plasma-Lyte, Ac = 27mEq/1), on coronary resistance (R) for the empty beating heart, and on vascular resistance (SVR) of 19 dogs on CPB. Control Rwith Ac = 0 (Rc) was obtained by adjusting flow to give a pressure of 90 ± 10mmHg (R = 532 ± 32 dynes.sec/cm5g, other Rs are given as a percentage of their respective Rc) . Continuous addition of Ac = 1.6 or 7.1 mEq/L of blood resulted in a rapid decrease in R to 34 ± 3 and 17 ± 2% of Rc, followed by a recovery to higher steady values of 53 ± 3 and 27 ± 2% respectively (p < 0.008). A bolus administration of 2mEq and 6mEq into the coronary circuit resulted in R dropping to 30 ± 5 and 17 ± 6% respectively. Rs obtained with Ac were compared to the Rs obtained for control 20sec reactive hyperaemia (35 ± 1 %), after 30 minutes global ischaemia (14 ± 1 %), and with the addition of bicarbonate (98 ± 2%). Ac did not change heart rate, but caused an increase in O2 consumption from 3.4 ± 0.4 to 4.8 ± 0.7ml/min/1 00g, (p < 0.038). Systemically, a bolus of 6mEq of Ac caused an immediate drop in SVR to 45 ± 5% of control. The property of Ac as a potent coronary and vascular dilator may need to be considered when Ac is used during cardiac surgery. Statistical comparisons were made with the paired t-test.
In-vitro evaluation of neonatal ECMO cannulae with regard to flow characteristics
Authors: Ehrén H. , Frenckner B. , Palmér K.
Published: November 2007

One of the crucial points in a neonatal ECMO circuit is to obtain adequate venous drainage from the cannula in the right jugular vein, as the vessel diameter limits the size of cannula that can be used. For this reason the design of the cannula is of utmost importance. The aim of this paper was to compare different commercially available ECMO cannulae, and to try to find the cannula which had the best flow characteristics. Venous cannulae were evaluated with regard to maximum drainage capacity at different hydrostatic levels. For arterial use, pressure drop over the cannulae at different flow rates was measured. Of the cannulae studied, those from Biomedicus and Elecath had the best flow characteristics for both venous and arterial use.
Supportive angioplasty utilizing the Bard cardiopulmonary support device
Authors: Harloff Michael
Published: November 2007

Bearing in mind that one case does not make a study, we would briefly like to elaborate on our exposure to cardiopulmonary support (CPS) at Milwaukee Heart Surgery Associates. CPS, in our opinion, is something that we will have to deal with whetherwe share the same cardiological philosophy or not. In order to provide the same standard of care to patients in the catheterization laboratory as we do for patients in surgery, it is incumbent upon us as perfusionists to be as knowledgeable and skilled as possible. A good rapport with the cardiologist and surgeon is essential in developing a workable protocol so as to avoid abuse of the technique. Direct visualization, with respect to cannulation and surgeon participation, is an ideal situation and is the standard of care in our practice. The cardiologist cannot perform supportive angioplasty utilizing CPS without consulting a surgeon, thereby minimizing some of the vascular complications that can arise as a result of nonsurgeon participation.
Serum protein changes during cardiopulmonary bypass: implications for host defence
Authors: Finlayson DC , Zaidan JR , Hunter RL , Check I. , Levy JH
Published: November 2007

A reduction in host defence capability, with increased risks of infection, occurs after open-heart surgery to a greater degree than after nonbypass surgery. Our costs for postoperative infections are large, about 15% of the total cost of open-heart surgery; better understanding of factors contributing to infection might allow reduction in these costs. Disturbance of the mechanisms involved in the handling of haemoglobin and iron may be among such factors, since free iron is a facultative requirement for the growth of all micro-organisms. We evaluated the change in serum proteins, particularly haptoglobin, during cardiopulmonary bypass. This study, in eight patients undergoing uncomplicated aortocoronary bypass employing a bubble oxygenator with haemodilution, and without clinical evidence of haemolysis, showed that free, unbound haptoglobin, evaluated by agarose gel electrophoresis, disappeared and was replaced by haemoglobin-bound haptoglobin within minutes of going on bypass. Such changes were not seen in three control patients who underwent comparably extensive surgery without bypass or in-bypass controls, in whom blood was evaluated after dilution with oxygenator prime. The disappearance of free haptoglobin and the possible disturbance of iron transport may have implications for host defences after bypass.