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During cardiopulmonary bypass (CPB), endothelium is exposed to multiple disturbances leading to significant vasomotor tone and vascular systemic resistances (VSR) level modifications. Properties of endothelial function on vascular tone were summarized herein. According bibliographic findings, physiological and clinical impacts of respectively halogenated agents and CPB concerning vasomotor tone were reported. Main effects of halogenated agents administered through oxygenator during CPB were also identified. Usually when administered above one MAC, halogenated agents decreased VSR during hypothermic bypass. Once those mechanisms summarized, increase of halogenated agent's effects on VSR during normothermic CPB was postulated. Assuming that decrease of VSR could be deleterious favoring severe vasoplegia event, clinical experience of administration of isoflurane during CPB among more 4000 patients was retrospectively reported. Incidence of severe vasoplegia was established to 9.5 % in the studied population and this result was similar as others. More over predicting factors of severe vasoplegia were the same as previously reported : severity of preoperative clinical status according Euroscore, hemodynamical instability before induction of anesthesia, surgical procedure complexity and CPB duration. Absence of deleterious effects in SVR decrease when administering isoflurane during normothermic CPB was assumed but prospective comparative studies comparing effects of halogenated agents and other anesthetic agents are needed in order to confirm these findings.

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OBJECTIVE: Hemofilter thrombosis occurs frequently during continuous veno-venous hemofiltration in intensive care units. Among coagulation disorders, antithrombin deficiency has been shown to be linked to hemofilter thrombosis. We investigated whether there was an association between antithrombin level activity and hemofilter thrombosis occurrence during early continuous hemofiltration following cardiopulmonary bypass. DESIGN: Prospective observational study. SETTING: Intensive care unit in University Teaching Hospital. PATIENTS AND PARTICIPANTS: Forty-eight consecutive patients. MEASUREMENTS AND RESULTS: Antithrombin level activity was measured just before the start of hemofiltration, and repeated at 24 h intervals for a total of 3 days. Hemofilter thrombosis episodes were recorded at each 24-h interval following antithrombin level activity measurement. Subjects were classified as HT when one or more episodes of hemofilter thrombosis appeared in this period and NHT if none. Morbidity parameters and mortality were recorded. Mean initial antithrombin level activity was low and not different in HT and NHT groups at day 0 (60.6 +/- 20.9% vs. 63.4 +/- 19.9%, P = 0.68). Antithrombin level activity was lower at day 1 (47.2 +/- 12.0% vs. 58.2 +/- 15.2%, P = 0.03) and day 2 (41.2 +/- 15.3% vs. 53.5 +/- 14.1%, P = 0.04) in HT group. However, antithrombin level activity was not shown to be predictive of HT in multivariate analysis. Morbidity and mortality did not differ significantly between the two groups. CONCLUSION: Only a weak association was found between antithrombin level activity and HT during early veno-venous hemofiltration post-cardiopulmonary bypass. This result was not confirmed in multivariate analysis. DESCRIPTOR: Renal failure: dialysis and hemofiltration.

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Lepirudin is an alternative anticoagulant therapy in heparin-induced thrombocytopenia (HIT) during cardiopulmonary bypass (CPB). We report a case of a female patient with HIT referred for aortocoronary bypass graft despite persistence of antibodies to platelet factor 4-heparin complexes. Anticoagulation management is described. Whole blood hirudin concentration attempted during CPB was above 4 microg ml(-1). To obtain this concentration, lepirudin administration was managed as follows: 0.1 mg kg(-1) h(-1) lepirudin during preoperative course, 0.2 mg kg(-1) bolus just before CPB and 0.2 mg kg(-1) in the priming solution, complementary boluses of 5 and 10 mg during procedure (according to whole blood ecarin clotting time). Aprotinin was administered simultaneously according to Royston protocol. Anticoagulation was monitored with whole blood ecarin time performed in the operation room (patient's whole blood was diluted one half and one third with normal whole blood; in vitro calibration curve was constructed using normal whole blood spiked with lepirudin). CPB duration was 73 min. When measured, whole blood hirudin concentration was 3.8-5.8 microg ml(-1). Total lepirudin administration was 44 mg. No haemorrhagic or thrombotic events were observed during surgical procedure and postoperative course. Despite lepirudin administration is not yet clearly precise for CPB procedure, its use seems adapted and safe in subjects without renal insufficiency but requiring precise coordination for anaesthesiological, surgical and biological teams.

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Percutaneous arterial cannulation is systematically used in cardiac surgery and reanimation for hemodynamic monitoring. It was frequently used in coronarography. Risk factors for occurrence of radial aneurysm after catheterization may include advanced age, longer duration of catheterization, hospitalization duration, and general infection with Staphylococcus aureus. We report an uncommon case of radial artery aneurysm, after cardiac surgery. We operated the patient with a good result.

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Cardiogenic shock in the acute phase of myocardial infarction still carries a high mortality. In young patients who cannot be revascularised by angioplasty, when medical therapy is failing, some workers recommend an energetic approach, even cardiac transplantation, often with the bridge of mechanical cardiac assistance. This is not possible everywhere, thus preventing possible myocardial salvage and resulting in fairly high mortality. The authors report two cases in which endoluminal revascularisation was not possible and so complete surgical revascularisation with left ventricular assistance was chosen. The two patients survived and one was successfully transplanted electively. This management may be proposed in young patients with multiple occlusions of large coronary arteries in post-infarction cardiogenic shock when medical management is failing despite intra-aortic balloon pumping.

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We prospectively studied spontaneous recovery from cisatracurium-induced neuromuscular block in 18 patients scheduled for cardiac surgery, and its suitability for fast-track cardiac surgery. Neuromuscular block was induced by an i.v. bolus (range 0.15-0.3 mg kg(-1)) and maintained by a continuous infusion (range 1.1-3.2 microg kg(-1) min(-1)) of cisatracurium until sternal closure. In the intensive care unit (ICU), spontaneous recovery was evaluated by the train-of-four (TOF) ratio measured at the adductor pollicis muscle. The ICU medical staff were unaware of the TOF ratios until sedation was stopped. At that time, if the TOF ratio was less than 0.9, sedation was recommenced. On arrival in ICU, all patients had residual paralysis. The mean time to reaching a TOF ratio of at least 0.9 was 102 min (range 74-144 min) after discontinuation of the cisatracurium infusion. Fifteen patients (83%) were successfully extubated during the first 8 h after stopping the cisatracurium infusion. Only one patient showed residual paralysis when sedation was discontinued. These results support the use of cisatracurium as a suitable neuromuscular blocking agent for fast-track cardiac surgery.

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BACKGROUND: During laparoscopic cholecystectomy the arterial-end-tidal CO2 gradient (Fa-ETCO2) has been variously shown to be unchanged, increased, decreased or even negative. The goal of this study was to evaluate Fa-ETCO2, and to determine the proper contribution of VECO2 and VA in regard to the increase of FETCO2. METHODS: Ventilatory patterns were studied in 15 ASA 1-2 patients (mean age +/- SD: 48.5 +/- 15.0) undergoing laparoscopic cholecystectomy, with intraperitoneal CO2 insufflation limited to 12 mmHg, 15 degrees head-up position, during general anaesthesia and controlled ventilation. The following were studied before, during and after the pneumoperitoneum: FaCO2, FETCO2, nasopharyngeal temperature; dead space ventilation, and expired volumes using the Single Breath Test for CO2. VA was calculated as the alveolar fraction of expired VT multipled by the respiratory frequency. RESULTS: During pneumoperitoneum it is shown that: 1) Fa-ETCO2 either decreases and becomes even negative (n = 8) (P < 0.01), or stays unchanged (n = 7), but never elevates; 2) VECO2 increases (peak value: +22.6%) (P < 0.01); 3) VA is unchanged, and 4) dead space ventilation, determined in 7 patients, remains unchanged. CONCLUSION: We conclude that only exogenous CO2 loading, and not VA, can explain such increase in FETCO2 and FaCO2, in cases of limited CO2 insufflating pressure in ASA 1-2 patients.

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The role of anaerobic bacteria in ventilator-associated pneumonia (VAP) has been little investigated. In this study we analyzed the incidence of anaerobes in patients with a first episode of bacteriologically documented VAP (> 10(3)CFU/ml), using protected specimen brushes (PSB). We particularly took care to preserve anaerobic conditions during transport and the microbiological procedure. Two groups were considered: group A with anaerobic bacteria recovered from PSB, with or without anaerobes, and group B with aerobic bacteria only. One hundred and thirty patients were included, 30 (23%) in group A, and 100 (77%) in group B. The main anaerobic strains isolated were Prevotella melaninogenica (36%), Fusobacterium nucleatum (17%), and Veillonella parvula (12%). Univariate analysis demonstrated that patients in group A were younger than those in group B (p < 0.05) and their simplified acute physiologic score was higher (p < 0.02). The percentage of patients receiving antibiotics before PSB did not differ significantly between group A (57%) and group B (35%). VAP with anaerobes occurred more often in patients orotracheally intubated than nasotracheally intubated (p < 0.02). Episodes of VAP involving anaerobic bacteria occurred more often in the first five days (early VAP) than after the fifth day (late VAP) (p < 0.05). The 3-mo mortality rate was similar in the two groups, but death occurred earlier in group B (p < 0.01). Multivariate analysis demonstrated that presence of altered level of consciousness (p = 0.0002), higher simplified acute physiologic score (p = 0.003), and admission to the medical ICU (p = 0.02) were the factors independently predisposing to the development of VAP with anaerobes.

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