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M Lamy

Publications and source records attributed to M Lamy.

At least 37 records · Page 2Linked to original sources
PubMed2001

Seventy-two hours hypothermic intestinal preservation study using a new perfluorocarbon emulsion.

We investigated the effect of a perfluorocarbon emulsion (FC) added to the University of Wisconsin (UW) solution on hypothermic (4 degrees C, 12-72h) preservation of rat small bowel grafts. The FC was 90%w/v perfluorooctylbromide, 2%w/v egg yolk phospholipids and 1.4%w/v mixed fluorocarbon-hydrocarbon molecular dowels. Four groups were defined: [1] UW flush and UW storage; [2] UW flush and FC storage; [3] flush with FC diluted 2 times with UW (FU) and FU storage; [4] FU flush and storage in oxygenated FU. Preservation was estimated with a histological score based on villus epithelium adhesion, on villus sloughing and on crypt cell adhesion to the basal membrane. Antioxidant potential was estimated by measurement of total thiol functions (SH) and activities of glutathione-peroxidase (GSH-P), superoxide dismutase (SOD) and catalase. FC in flush improved preservation during the first 24h (p<0.01). Storage in FC appeared superior to UW for the first 24h (p<0.01). Oxygenation (100% O2) of the storage medium yielded superior results at 12h and 24h (p<0.01 and p<0.001 versus group [1] respectively). After 72h, SOD and catalase activities increased in groups [3] and [4], and SOD decreased in group [1] (p<0.05). SH progressively decreased in group [1] (p<0.05) and GSH-P increased at 24 and 48h in groups [3] and [4] (p<0.01). The increase of O2 in the perfusion flush or storage medium ameliorated the preservation status and protected the antioxidant potential of the small bowel.

Animals↗
PubMed2001

An animal model of response and nonresponse to inhaled nitric oxide in endotoxin-induced lung injury.

STUDY OBJECTIVE: Oxygenation may be improved in 40 to 60% of ARDS patients by inhalation of nitric oxide (NO). We have studied the response to inhaled NO in porcine acute lung injury 4 h and 6 h after onset of a 2-h endotoxin infusion (30 microg/kg/h), hypothesizing that a responder may change to a nonresponder over time and with progression of lung injury. DESIGN: Animal study. SETTING: Experimental laboratory in a university hospital. INTERVENTIONS AND MEASUREMENTS: We studied eight pigs under general anesthesia (mean weight, 26.2 kg) receiving mechanical ventilation adjusted to normocapnia, with a fraction of inspired oxygen (FIO(2)) of 0.5 to 1.0. Blood gases, endotoxin concentration, and central hemodynamics were measured hourly, and ventilation-perfusion (/) relationships were assessed by multiple inert gas elimination technique before and after inhalation of NO. NO was delivered at 40 ppm for 10 min at 4 h and 6 h of endotoxin exposure. RESULTS: Seven of eight pigs were responders to NO at 4 h, defined as a > or = 20% increase in oxygenation index (PaO(2)/FIO(2)) [223 +/- 43 to 330 +/- 56 mm Hg; p = 0.001]. The same pigs exhibited a > or = 20% fall in mean pulmonary artery pressure (39.4 +/- 2.2 to 30.0 +/- 2.1 mm Hg; p < 0.001). The response correlated to the perfusion to "normal /" regions (r = - 0.82) and negatively to shunt and dead space ventilation (r = 0.76 and r = 0.87, respectively). At 6 h, seven of eight pigs were nonresponders, despite unaltered hemodynamics and gas exchange. Correlations at 4 h between physiologic variables and response to NO were abolished. The logarithmic SDs of the perfusion distribution, a measure of the degree of / mismatch, increased significantly from 4 to 6 h (p = 0.04). CONCLUSION: Response to inhaled NO is abolished over time in endotoxin-induced ARDS pig lungs. The response seems to be related to the degree of / mismatch, which may indicate an important role of hypoxic pulmonary vasoconstriction.

Administration, Inhalation↗
PubMed2001

[Ultra-fast opiate detoxification under general anesthesia: preliminary results of the Liege protocol].

Many studies support the hypothesis of a substantial benefit in inducing an Opiate Receptor Blockade through a Rapid Opiate Detoxification under general Anaesthesia (RODA) in opiate dependent patients. However, prospective studies and long term evaluation of the technique are lacking. In order to evaluate long-term abstinence rates after a RODA among a sample of opiate addicts, a study was started in March 1999 at the University of Liège. To date, 45 patients were evaluated (mean age: 29 +/- 5 years) with a mean opiate dependence duration of 8 +/- 4 years. Most of them were both heroin and methadone dependent; 42.2% of them were included while 31.1% did not complete the whole inclusion procedure and 26.7% were excluded. None experienced severe withdrawal symptoms. At six months, abstinence rate was 67% and 46% at one year. These preliminary results suggest the interest of the procedure in carefully selected patients.

Adult↗
PubMed2001

Transition between anesthesia and post-operative analgesia: relevance of intra-operative administration of analgesics.

The rapid awakening without residual analgesic effect seen with the new "fast-in-fast-out" anesthetic agents forces us to anticipate post-operative pain management. More then ever, "balanced analgesia" appears the key for successful transition between anesthesia and post-operative analgesia. This review focuses on practical aspects seeking to answer the following questions: which analgesics should be used?; how should they be given?; at what stage of the anesthetic time should they be injected? In the absence of a loco-regional technique, analgesics must be given before the end of surgery to obtain a quiet awakening. The transition in this delicate period may be facilitated by the intra-operative use of various adjuvant therapies such as ketamine, lidocaine infusion, clonidine, and magnesium, that reduce the needs for opioid and/or post-operative pain severity. All non-opioid analgesics (propacetamol, NSAIDs, tramadol) must be given according to their pharmacokinetic characteristics, indications and contraindications to ensure the required analgesic effect is effective at the time of awakening. If tramadol is not used, an initial dose of a long-acting opioid should be given 20-30 minutes before the end of surgery. Insufficient analgesia must be corrected by titrating an opioid intravenously before allowing the patient to control his/her analgesia using a PCA pump.

Analgesics↗
PubMed2001

[Alpha-1-antitrypsin deficiency. An indication for pediatric liver transplantation].

Alpha-1-antitrypsin deficiency is the most common inborn error of metabolism leading to liver transplantation, and the second cause of liver transplantation in children after biliary atresia. The authors report the case of a 6-year-old girl, who was suffering from end-stage liver disease secondary to alpha-1-antitrypsin deficiency. She was successfully treated by whole liver transplantation, the hepatic graft coming from a 3-year-old donor. Three months later she went back to school. The authors discuss the pathogenesis and the natural history of this frequent cause of liver transplantation in children.

Child↗
PubMed2001

[The global impression technic in fixed dentures].

The global impression technique allows to obtain in a single stage the impression of the abutment as well as their neighboring teeth. This technique often requires the placement of one or two retraction cords in the sulcus. The impression technique herein described is the double mix method. This method is based on the use of two elastomers with different viscosities, but from the same group thus allowing a simultaneous polymerization.

Dental Abutments↗
PubMed2001

[Single-tooth impressions using metal-resin matrixes].

The metallic-resinous frame impression technique is based on the impression of single abutments encompassed in a global one, with or without transfert copings. For single tooth impression, this technique is the easiest and the most practical alternative to the one using thermoplastic paste. The aim of this article is to describe, step-by-step, the impression taking procedures using the metallic-resinous frame technique.

Acrylic Resins↗
PubMed2000

HREM of CoSi2/SiC heterophase interface: facts and artifacts in the interface distance profile measurements

When studying heterophase interfaces, one of the ultimate goals is to determine the local distortions and to extract a chemical profile. In this respect, HREM is a powerful tool. Nevertheless, the non-linearity of the image formation leads to artifacts both in the images and in the distance profiles extracted from the images. The present SiC/silicide interface study illustrates the misinterpretation, which might arise from measurements made on images recorded under limited experimental conditions.

Journal Article↗
PubMed2000

Nitrated proteins in bronchoalveolar lavage fluid of patients at risk of ventilator-associated bronchopneumonia.

The study was designed to identify markers of oxidative injury, related to the nitric oxide derived cascade, in bronchoalveolar lavage (BAL) fluid from intensive care patients suspected of ventilator-associated pneumonia (VAP) and/or acute respiratory distress syndrome (ARDS). Thirty-eight patients developing VAP and/or ARDS (VAP/ARDS group) were compared to 20 ventilated patients without VAP/ARDS (control group). Myeloperoxidase (MPO) and elastase, taken as markers of neutrophil activation were measured by enzymatic techniques, and nitrated proteins (NTPs) by an immunological method. The cytotoxicity of the BAL fluid was tested using cultured human epithelial alveolar cells by the release of pre-incorporated 51Cr. Mean NTP concentration and, MPO and elastase activities were different between the VAP/ARDS and control groups (p<0.05 for NTPs; p<0.005 for MPO; p<0.005 for elastase). NTP concentration correlated with MPO and elastase activity and neutrophil number (r=0.93, 0.91 and 0.87, respectively), but not to protein concentration and arterial oxygen tension/inspiratory oxygen fraction. The cytotoxicity of BAL correlated with NTP concentration (r=0.92) and MPO activity (r=0.89). It was concluded that the concentrations of nitrated proteins in bronchoalveolar lavage fluid correlated with the oxidant activity of neutrophils and that, bronchoalveolar lavage fluid cytotoxicity was correlated with the nitrated protein concentration and may be mediated by oxidants.

Adolescent↗
PubMed2000

Effects of propofol on endothelial cells subjected to a peroxynitrite donor (SIN-1).

We investigated the effect of propofol on endothelial cells subjected to the peroxynitrite (ONOO-) donor 3-morpholino sydnonimine (SIN-1). Cells were incubated overnight with 0.5, 1.0 or 2.0 mM SIN-1, with or without 10-3 M propofol (Diprivan). Cytotoxicity, assessed by measuring the release of pre-incorporated 51Cr, increased when the concentration of SIN-1 increased, and was significantly decreased by 10-3 M propofol (90%, 78% and 28% of protection against 0.5, 1.0 and 2.0 mM SIN-1, respectively). Cell protection against 1 mM SIN-1 was tested with 0.03-1.0 mM propofol and this was compared to tyrosine, a target molecule for peroxynitrite. Propofol protected cells in a dose-dependent manner (r = 0.98; p < 0.001) and was as effective as tyrosine. Finally, using high-performance liquid chromatography, we demonstrated that propofol reacted with ONOO- more rapidly than did tyrosine, inhibiting nitrotyrosine formation. In the absence of propofol, 3.5 mM ONOO- with 1 mM tyrosine yielded 39.6% nitrotyrosine, but nitrotyrosine was not produced when 5 mM propofol was added. We conclude that propofol protects endothelial cells against the toxicity of ONOO-. The anti-oxidant properties of propofol can be partially attributed to its scavenging effect on peroxynitrite, a property that might be relevant in pathological situations involving a significant contribution of peroxynitrite to tissue damage.

Anesthetics, Intravenous↗
PubMed2000

Auditory processing in the vegetative state.

H(2)(15)O-PET was used to investigate changes in regional cerebral blood flow in response to auditory stimulation in patients in the vegetative state. Five patients in a vegetative state of hypoxic origin were compared with 18 age-matched controls. In addition, the cerebral metabolism of these patients and 53 age-matched controls was studied using [(18)F]fluorodeoxyglucose. In control subjects, auditory click stimuli activated bilateral auditory cortices [Brodmann areas (BA) 41 and 42] and the contralateral auditory association cortices (BA 22). In the patients, although resting metabolism was decreased to 61% of normal values, bilateral auditory areas 41 and 42 showed activation as seen in the controls, but the temporoparietal junction cortex (BA 22) failed to be activated. Moreover, the auditory association cortex was functionally disconnected from the posterior parietal association area (BA 40), the anterior cingulate cortex (BA 24) and the hippocampus, as revealed by psychophysiological interaction analysis. Thus, despite altered resting metabolism, the auditory primary cortices were still activated during external stimulation, whereas hierarchically higher-order multi- modal association areas were not. Such a cascade of functional disconnections along the auditory cortical pathways, from the primary auditory areas to multimodal and limbic areas, suggests that the residual cortical processing observed in the vegetative state cannot lead to the integrative processes that are thought to be necessary for the attainment of the normal level of awareness.

Acoustic Stimulation↗
PubMed2000

Neural mechanisms of antinociceptive effects of hypnosis.

BACKGROUND: The neural mechanisms underlying the modulation of pain perception by hypnosis remain obscure. In this study, we used positron emission tomography in 11 healthy volunteers to identify the brain areas in which hypnosis modulates cerebral responses to a noxious stimulus. METHODS: The protocol used a factorial design with two factors: state (hypnotic state, resting state, mental imagery) and stimulation (warm non-noxious vs. hot noxious stimuli applied to right thenar eminence). Two cerebral blood flow scans were obtained with the 15O-water technique during each condition. After each scan, the subject was asked to rate pain sensation and unpleasantness. Statistical parametric mapping was used to determine the main effects of noxious stimulation and hypnotic state as well as state-by-stimulation interactions (i.e., brain areas that would be more or less activated in hypnosis than in control conditions, under noxious stimulation). RESULTS: Hypnosis decreased both pain sensation and the unpleasantness of noxious stimuli. Noxious stimulation caused an increase in regional cerebral blood flow in the thalamic nuclei and anterior cingulate and insular cortices. The hypnotic state induced a significant activation of a right-sided extrastriate area and the anterior cingulate cortex. The interaction analysis showed that the activity in the anterior (mid-)cingulate cortex was related to pain perception and unpleasantness differently in the hypnotic state than in control situations. CONCLUSIONS: Both intensity and unpleasantness of the noxious stimuli are reduced during the hypnotic state. In addition, hypnotic modulation of pain is mediated by the anterior cingulate cortex.

Adult↗
PubMed2000

Correlation between endotoxin level and bacterial count in bronchoalveolar lavage fluid of ventilated patients.

OBJECTIVE: To assess the predictive value of the endotoxin level in the bronchoalveolar lavage (BAL) and to propose to the clinician a guide in the diagnosis of gram-negative bacterial (GNB) pneumonia. DESIGN: Retrospective and prospective studies to investigate the relation between endotoxin level and quantitative bacterial culture of BAL and to test the predictive value of a defined threshold. SETTING: University hospital general intensive care unit. PATIENTS: In the first part of the study, 77 consecutive ventilated patients with clinical suspicion of nosocomial pneumonia between January 1995 and January 1996. In the second part of the study, 93 consecutive ventilated patients studied prospectively between February 1996 and April 1997. MEASUREMENTS AND MAIN RESULTS: Quantitative cultures for aerobic bacteria were performed directly from the fluid. Bacterial species were determined with standard techniques. The detection of endotoxin in BAL was made using a quantitative chromogenic Limulus assay. In the retrospective analysis, a significant correlation between quantitative GNB cultures and BAL endotoxin levels was observed (r2 = 0.60, p < .0001). An endotoxin level > or = 4 endotoxin units/mL (EU/mL) distinguishes patients with a significant GNB count from colonized patients with a sensitivity of 92.6%, a specificity of 81.4% and a correct classification rate of 84.9%. In the prospective analysis, the 4 EU/mL threshold permits identification of infected patients with a sensitivity of 82.2%, a specificity of 95.6%, and a correct classification rate of 90.3%. The receiver operating characteristic curve analysis showed that the Limulus assay still had a good discrimination power in the prediction of significant bacterial count in BAL fluid. CONCLUSIONS: Endotoxin detection immediately after bronchoscopy is a distinct advantage to the clinician because antimicrobial gram-negative therapy may be immediately justified according to the results.

Adolescent↗
PubMed2000

Evaluation of acute normovolemic hemodilution for surgical repair of craniosynostosis.

This clinical report investigated the potential benefit of acute normovolemic hemodilution (ANH) as a blood-saving technique in the surgical repair of craniosynostosis. Over a 4-year period, 34 healthy children undergoing surgical repair of scaphocephaly or pachycephaly were randomly assigned to two groups of 17 patients each. Patients of the first group (ANH group) were submitted to ANH (target Ht: 25%) immediately before surgery and patients of the second group (Control group) were not. During surgery, estimated blood loss was compensated with a 5% albumin solution and no autologous or homologous blood was transfused. At the end of surgery, intraoperative blood loss (mean +/- SD) calculated on the basis of the Ht value and the children weight was 21.3+/-8% of the estimated blood volume (EBV) in the ANH group and 24+/-6.6% in the Control group. Children of the ANH group received their autologous blood (18.9+/-3.3% of EBV) systematically at the end of surgery. In the postoperative period, homologous blood was transfused when the Ht value was equal or less than 21%. Both groups were comparable regarding age, weight, type of craniosynostosis, duration of surgery, EBV, and preoperative Ht value. No difference was observed between ANH and Control groups in the number of patients who received homologous blood (15/17 and 14/17, respectively), in the amount of homologous blood transfused (17+/-4.7% and 19.6+/-6.3% of the EBV, respectively), and in the Ht value before hospital discharge (29.4+/-5.0% and 30.7+/-4.9%, respectively). In conclusion, this report suggests that ANH reduces neither the incidence of homologous transfusion nor the amount of homologous blood transfused in this series of children undergoing surgical repair of craniosynostosis.

Albumins↗
PubMed2000

Cytotoxicity of stimulated equine neutrophils on equine endothelial cells in culture.

We studied the interactions of isolated equine neutrophils with endothelial cells in culture, mimicking a situation of acute inflammation. Our main purpose was to demonstrate that the supernatant of activated neutrophils was sufficient to damage endothelial cells. Equine endothelial cells (from carotid arteries) were covered either with increased numbers of equine neutrophils stimulated by phorbol myristate acetate, or with the supernatant collected after an in vitro stimulation of the neutrophils. Cytotoxicity was estimated by the release of preincorporated 51Cr, and by light microscopy observations. To assert the specific role of reactive oxygen species, endothelial cells were treated by the hypoxanthine/xanthine oxidase (X/XOx) system (production of superoxide anion and hydrogen peroxide), and by hypochlorite (product of the activity of myeloperoxidase). A strong cytotoxicity was found with stimulated neutrophils; microscopic observations indicated a loss of 50% of the endothelial cells and morphological alterations in the remaining cells. The supernatant of stimulated neutrophils was cytotoxic, in correlation with the number of neutrophils used to obtain the supernatant, and with the supernatant concentration of myeloperoxidase. The cytotoxicity of the X/XOx system was weak, but was increased by myeloperoxidase. Hypochlorite was highly toxic. We concluded that the supernatant of stimulated neutrophils was sufficient to obtain cytotoxic effects on the endothelium, in the absence of a direct contact between endothelium and neutrophils, and that this cytotoxicity was mainly linked to the activity of myeloperoxidase. From these in vitro results, it can be extrapolated that in pathologies characterised by an important activation of neutrophils, damage can spread to cells and tissues away from the inflammation focus.

Animals↗
PubMed2000

Sedation, analgesia and anesthesia for interventional radiological procedures in adults. Part II. Recommendations for interventional radiologists.

Benzodiazepines are given orally as a premedication before an interventional radiological procedure. Local analgesia is achieved by drugs such as lidocaine, bupivacaine or ropivacaine. General analgesia is obtained by non opioid analgesics and opioid narcotics. For intravenous sedation, benzodiazepines such as ketamine or propofol should be administered under the supervision of an anesthesiologist. A preprocedure consultation with the anesthesiologist is recommended. Monitoring equipments, drugs and nursing staff assistance should be provided in the interventional suite. Vital signs should be monitored for several hours until patient's discharge. Close collaboration between anesthesiologists and interventional radiologists is a prerequisite for achieving high standard sedation and analgesia.

Adult↗
PubMed2000

[The Hemovigilance Commission of the University Hospital Center].

As suggested by the National Blood Council, a Hemovigilance Committee was set up in the University Hospital of Liège in 1995. A multidisciplinary discussion takes place on any action aiming at the improvement of transfusion safety, and the follow-up of its implementation. The first issue to be discussed was the set up of a detailed documentation of all blood transfusions. The data are now recorded on a single document allowing proper identification of people and products involved, and of the eventual incidents. This document has lead to a better transfusion safety and to an improved administrative management of blood transfusion. The Commission has been coordinating two multi-centric studies analyzing the consumption of fresh blood products and the incidence of transfusion reactions. Among blood-saving policies, autologous transfusion and volume reduction of samples drawn for laboratory purposes have been discussed. Other measures were taken to improve the labeling of samples for cross-mach and to actively follow-up transfusion reactions. By its actions and advises, the Commission aims to direct strategies towards a safe and rational use of blood products.

Belgium↗