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Introduction : récemment, la norépinéphrine a été proposée comme vasopresseur pour le maintien de la pression artérielle (PA) materno-foetale lors de la césarienne sous rachianesthésie. L’objectif principal était d’évaluer les conséquences fœtales de cette perfusion continue. Méthodologie : nous avons réalisé une étude observationnelle, rétrospective, de type avant-après, mono centrique de mai 2016 à novembre 2017 incluant toutes les patientes bénéficiant d’une césarienne sous rachianesthésie. Durant la 1ère période (groupe classique, C), des boli d’éphédrine-phényléphrine étaient réalisés en cas de baisse de pression artérielle moyenne (PAM) supérieure à 20 %. Durant la 2e période, une perfusion continue de norépinéphrine (20 μg/mL, groupe N) était administrée avec un objectif de PAM similaire au groupe C. L’objectif principal était de comparer le taux de lactate au cordon. Les objectifs secondaires étaient les autres critères fœtaux (pH artériel et veineux au cordon, score Apgar, hospitalisation), et les critères maternels (PA, recours aux vasopresseurs). Résultats : sur 265 patientes éligibles, 134 ont été incluses dans le groupe C et 111 dans le groupe N, sans différence sur les données démographiques et obstétricales. Les lactates au cordon étaient plus bas dans le groupe C par rapport au groupe N (2.0 vs 2.4, p=0.03), sans différences significatives sur les valeurs de pH, les scores Apgar et les mesures de réanimation fœtale. Les PA maternelles étaient similaires entre les deux groupes. Conclusion : la norépinéphrine procure des profils métaboliques plus optimaux que les boli classiques d’éphédrine-phényléphrine

Introduction : La douleur abdominale aiguë non traumatique peut témoigner d’une pathologie bénigne ou grave mettant en jeu le pronostic vital. De nombreux marqueurs biologiques ont été évalués mais n’ont pas démontré à eux seuls de véritable intérêt en termes d’orientation diagnostique et le gold standard reste le scanner. Le lactate est un métabolite pouvant augmenter dans des situations pathologiques telles que le sepsis, l’hypoxie cellulaire, les états de choc. Notre objectif principal était de déterminer si la lactatémie veineuse avait un intérêt en tant qu’outil de triage aux urgences devant une douleur abdominale aiguë en facteur prédictif de gravité, défini par une hospitalisation, et secondairement de rechercher un lien entre l’élévation de la lactatémie et le recours à une intervention chirurgicale, de rechercher un lien entre l’élévation de la lactatémie et certaines pathologies. Matériel et méthode : Nous avons réalisé une étude observationnelle, prospective, monocentrique dans le service d’urgences adultes du Pr Michelet à la Timone, du 8 juin au 7 juillet 2017 et du 19 au 25 février 2018. Les patients venus pour douleur abdominale aiguë bénéficiaient dès leur arrivée d’un dosage de la lactatémie veineuse. Résultats : Au total, 125 patient ont été inclus. Les patients avec douleur abdominale aiguë hospitalisés avaient une élévation significative de la lactatémie (p < 0,01). La spécificité de la lactatémie était de 77,1% mais la sensibilité de 56,4%. Sa valeur prédictive négative était de 78,3% et sa valeur prédictive positive de 54,8%. Il n’y avait pas de lien significatif entre l’élévation de la lactatémie et le recours à une intervention chirurgicale (p = 0,069). Il y avait une élévation significative de la lactatémie chez les patients avec une occlusion (p = 0,003). Une analyse en sous-groupe avec stratification du taux de lactates montrait un lien significatif entre l’élévation franche de la lactatémie supérieure à 3mmol/L et l’ischémie mésentérique (p < 0,01). Il y avait une élévation significative de la lactatémie chez les patients présentant des vomissements (p=0,003), ou des signes de choc (p=0,020). Conclusion : Notre étude validait notre hypothèse principale en démontrant qu’une élévation du taux de lactates était un facteur de gravité chez les patients présentant une douleur abdominale, les patients avec une élévation de la lactatémie étant plus hospitalisés. Cependant, sa sensibilité et spécificité étant plutôt mitigées, ce dosage ne devrait pas se substituer à l’examen approfondi du clinicien et à l’analyse des autres marqueurs biologiques qui ont amplement fait leurs preuves. Nous n’avons pas réussi à établir de lien entre l’élévation de la lactatémie et le recours à une intervention chirurgicale en urgence, mais ce résultat était probablement dû à notre faible effectif de patients opérés (17). Son dosage semblait intéressant devant un tableau évocateur d’occlusion intestinale en termes d’orientation diagnostique, ou devant une douleur abdominale associée à des vomissements pour rechercher des signes de gravité. Cependant, notre étude avait un effectif trop faible pour pouvoir apporter de vraies réponses à toutes nos hypothèses et il serait intéressant de réaliser une étude à plus grande échelle sur plusieurs mois, avec plusieurs intervenants qui feraient un recueil prospectif basé sur un questionnaire standardisé.

Hyperlactatemia is associated with an ominous prognosis in critical illness and must be rapidly detected. Lactate is produced by glycolysis through reduction of pyruvate, itself oxidized in the mitochondria. It is transported to the liver and converted to glucose through gluconeogenesis (Cori's cycle). Hyperlactatemia can result from excessive production or reduced clearance. Excess production can occur in aerobic conditions, following an increase in pyruvate generation, or in anaerobic conditions, due to impaired pyruvate oxidation. Reduced lactate clearance occurs as a result of liver hypoperfusion or hepatic failure. Lactate/pyruvate ratio, as well as the concomitant existence of metabolic acidosis (lactic acidosis), help distinguish the different mechanisms leading to hyperlactatemia, which are reviewed in detail in this article.

The interest of cerebral energy metabolism monitoring in the care of patients suffering from aneurysmal subarachnoid hemorrhage (aSAH) currently remains controversial because of the absence of decision making thresholds applicable in practice. This work aimed to reassess the value of biochemical parameters from three techniques, intracerebral microdialysis (cMD), the measurement of brain tissue oxygen pressure (PbtO2), the retrograde jugular catheter to predict the functional outcome and diagnose the occurrence of secondary ischemia.It seems obvious that this monitoring can predict at the individual level the functional long-term outcome. The metabolic ratio (MR) or association of MR with the parameters of the two other techniques (lactate/pyruvate >40, hypoxic lactate) represent potential prognostic biomarkers.It is however difficult to conclude on the interest of such monitoring to diagnose secondary ischemic complications. Although it has been shown that the MR can be considered as a biomarker, it is currently not possible to conclude on the two local approaches (cMD and PbtO2). Nevertheless, implantation rules have been identified and validated for their rapid application in clinical practice.Finally, the monitoring of brain energy metabolism remains a reference technique in the care of serious aSAH patients, especially to predict functional long-term outcome because decision thresholds have been identified and thus will facilitate the use of this kind of monitoring, L'intérêt du suivi du métabolisme énergétique cérébral dans la prise en charge des patients victimes d'hémorragie sous-arachnoïdienne anévrismale (aSAH) grave reste actuellement controversé en raison de l'absence de valeurs seuils décisionnelles applicables en pratique. Ce travail avait pour objectif de réévaluer l'intérêt des paramètres biochimiques de trois techniques, la microdialyse intracérébrale (cMD), la mesure de la pression tissulaire cérébrale en oxygène (PbtO2) et le cathéter rétrograde jugulaire, pour prédire l’issue fonctionnelle de ces patients et diagnostiquer la survenue d'un infarctus. Il parait évident que ce suivi peut permettre de prédire à l'échelon individuel l'issue fonctionnelle à long terme. Le metabolic ratio (MR) ou l'association de ce MR avec des paramètres des deux autres techniques (ratio Lactate/Pyruvate >40, lactates hypoxiques) représentent des potentiels biomarqueurs pronostiques. Il est en revanche difficile de conclure sur l'intérêt de ce suivi pour diagnostiquer les complications ischémiques secondaires. Bien qu'il ait été montré que le MR peut être considéré comme un biomarqueur, il n'est pas possible de conclure actuellement sur les deux approches locales (cMD et PbtO2). Des règles d'implantation ont tout de même pu être identifiées et validées permettant leur application rapide en pratique courante. Au final, le suivi du métabolisme énergétique cérébral doit être envisagé dans la prise en charge des patients aSAH graves notamment pour prédire l'issue fonctionnelle à long terme car des valeurs seuils décisionnelles ont été identifiées et faciliteront ainsi l'utilisation de ce type de monitoring

The interest of cerebral energy metabolism monitoring in the care of patients suffering from aneurysmal subarachnoid hemorrhage (aSAH) currently remains controversial because of the absence of decision making thresholds applicable in practice. This work aimed to reassess the value of biochemical parameters from three techniques, intracerebral microdialysis (cMD), the measurement of brain tissue oxygen pressure (PbtO2), the retrograde jugular catheter to predict the functional outcome and diagnose the occurrence of secondary ischemia.It seems obvious that this monitoring can predict at the individual level the functional long-term outcome. The metabolic ratio (MR) or association of MR with the parameters of the two other techniques (lactate/pyruvate >40, hypoxic lactate) represent potential prognostic biomarkers.It is however difficult to conclude on the interest of such monitoring to diagnose secondary ischemic complications. Although it has been shown that the MR can be considered as a biomarker, it is currently not possible to conclude on the two local approaches (cMD and PbtO2). Nevertheless, implantation rules have been identified and validated for their rapid application in clinical practice.Finally, the monitoring of brain energy metabolism remains a reference technique in the care of serious aSAH patients, especially to predict functional long-term outcome because decision thresholds have been identified and thus will facilitate the use of this kind of monitoring, L'intérêt du suivi du métabolisme énergétique cérébral dans la prise en charge des patients victimes d'hémorragie sous-arachnoïdienne anévrismale (aSAH) grave reste actuellement controversé en raison de l'absence de valeurs seuils décisionnelles applicables en pratique. Ce travail avait pour objectif de réévaluer l'intérêt des paramètres biochimiques de trois techniques, la microdialyse intracérébrale (cMD), la mesure de la pression tissulaire cérébrale en oxygène (PbtO2) et le cathéter rétrograde jugulaire, pour prédire l’issue fonctionnelle de ces patients et diagnostiquer la survenue d'un infarctus. Il parait évident que ce suivi peut permettre de prédire à l'échelon individuel l'issue fonctionnelle à long terme. Le metabolic ratio (MR) ou l'association de ce MR avec des paramètres des deux autres techniques (ratio Lactate/Pyruvate >40, lactates hypoxiques) représentent des potentiels biomarqueurs pronostiques. Il est en revanche difficile de conclure sur l'intérêt de ce suivi pour diagnostiquer les complications ischémiques secondaires. Bien qu'il ait été montré que le MR peut être considéré comme un biomarqueur, il n'est pas possible de conclure actuellement sur les deux approches locales (cMD et PbtO2). Des règles d'implantation ont tout de même pu être identifiées et validées permettant leur application rapide en pratique courante. Au final, le suivi du métabolisme énergétique cérébral doit être envisagé dans la prise en charge des patients aSAH graves notamment pour prédire l'issue fonctionnelle à long terme car des valeurs seuils décisionnelles ont été identifiées et faciliteront ainsi l'utilisation de ce type de monitoring

La mortalité canine néonatale (entre la naissance et 21 jours de vie) est élevée et cause des pertes économiques importantes pour les éleveurs. La majeure partie de la mortalité survient lors de la première semaine de vie. L’objectif de cette étude est d’identifier des paramètres mesurables à la naissance ou au cours des 24 premières heures de vie qui permettraient d’identifier les chiots à risque de mortalité afin que l’éleveur puisse les prendre en charge. 347 chiots de 15 races différentes issus d’un même élevage ont été inclus dans cette étude. Le taux de mortalité entre 0 et 21 jours a été de 20,2%. Les paramètres significativement liés au risque de mortalité avant J21 furent le score d’APGAR, la glycémie et la densité urinaire à 24h de vie, ainsi que l’évolution de la glycémie entre J0 et J1. Ce travail suggère l’importance du métabolisme et des ressources énergétiques dans la mortalité néonatale canine. Il permet d’améliorer l’identification et ainsi la prise en charge des chiots à risque afin de prévenir la mortalité.

To assess the quality of intrapartum care in birth asphyxia cases.Prospective analysis of all cases of birth asphyxia in nine maternity units during one year (2010). Birth asphyxia was defined as the combination of at least one clinical factor (Apgar≤7 at 5 minutes, signs of encephalopathy at birth) and at least one biological factor in cord (pH≤7, BD≥12 mmol/L, lactates10 mmol/L). These cases were analyzed with a peer review from French guidelines 2007.Fifty cases of birth asphyxia were identified. After peer-review, they were defined as 46% non preventable, 27% possibly preventable, 24% definitely preventable and 3% not established. The main causes have been described as (i) misinterpretation of CTG during the first and second stages of labour, (ii) delayed response time to CTG anomalies and (iii) prolonged second stage.In half of the cases of birth asphyxia, this dreaded event was considered as preventable by a group of peers.

The graded exercise test (GXT) is used to measure the exercise capacity of patients with chronic obstructive pulmonary disease (COPD). To do this GXT must be maximal (exhaustive). However, the value of the blood lactate at the GXT endpoint [La(-)max] or after a recovery period of three minutes [La(-)recovery], to confirm that the GXT is maximal, remains controversial. The purpose of the present study is to determine a threshold of [La(-)max] and/or [La(-)recovery], which confirms the exhaustiveness of GXT in patients with COPD.Thirty-six patients with COPD performed a GXT until exhaustion on a cycle ergometer. During the GXT cardiorespiratory parameters, [La(-)max] and [La(-)recovery] were measured. When at least three out of five of the most frequently used criteria to confirm exhaustion were met, GXT was considered as maximal. Conversely, GXT was considered as sub-maximal when less three criteria were observed. The receiver operating characteristic (ROC) curves were analyzed.For [La(-)max] the areas under the ROC curve and the areas under the diagonal were not significantly different (P=0.16). For [La(-)recovery] the ROC curve inflected itself at 5.8mmol/L (sensitivity=0.92 and specificity=0.56).It was not possible to use [La(-)max] to confirm exhaustion in our population. However, [La(-)recovery]5.8mmol/L may help to confirm non-exhaustion during GXT in patients with COPD. Below this blood lactate threshold 93% patients performed a sub-maximal GXT.

Fluid therapy is one of the major elements of severe sepsis and septic shock management. A systematic initial fluid bolus is recommended before evaluation of left ventricular filling pressure by the use of indicators of fluid responsiveness, preferentially dynamic ones. A massive fluid therapy could be damaging for the patient. Dynamic indicators of fluid responsiveness are not often relevant in the emergency department. This study was aimed to evaluate the use of indicators of fluid responsiveness by emergency practitioners during septic shock management.Cross sectional survey using anonymous self-questionnaire.We included all practitioners working in public emergency department of Languedoc-Roussillon (France). Primary-end point was the use of one indicator of fluid responsiveness at least. Uni- and multivariate analysis was conducted to find associated factors.Of 232 practitioners included, we collected 149 questionnaires (response rate=64%). Hundred and eight practitioners (72% [64-79%]) used at least one indicator of fluid responsiveness. Fifty-six practitioners (38% [30-46%]) used echocardiography, 54 practitioners (36% [29-44%]) used blood lactate concentration, 45 practitioners (30% [23-38%]) used passive leg raising. The use of indicators of fluid responsiveness is associated with easy access to echography device (odd ratio=2.94 [1.16-7.62], P=0.03).Emergency practitioners use preferentially less invasive and less time-consuming indicators of fluid responsiveness.

Hyperlactataemia, a marker of poor prognosis in intensive care patients, is most frequently found in cases of acute circulatory failure ; however, it may be due to factors other than cellular hypoxia. The level of blood lactate is determined by the balance between its production and its elimination, which can be influenced by various factors. For example, the influence of medication on blood lactate levels should not be underestimated, whether in anaesthesiology, with the use of propofol, or with certain anti-retrovirals in HIV seropositive patients. And in oncology, blood lactate can derive from anaerobic metabolism, characteristic of tumour cells. The differential diagnosis of hyperlactataemia can, therefore, sometimes be more complex than initially thought.

We report the case of a 35-year-old woman hospitalized in intensive care unit after valpromide self-poisoning (Dépamide). The dose supposed to be taken was 15 g. The patient eleven hours after ingestion, presented, a coma with bilateral non-reactive mydriasis, justifying intubation and mechanical ventilation. An acidosis (pH = 7.24), a hyperlactatemia (2.72 mmol/L), a hyperammonemia (328.9 micromol/L), and were diagnosed valproic acid plasmatic concentration was 1190 microg/mL at 22 hours. Symptomatic treatment and L-carnitine therapy (50 mg/kg/12h) normalized the action of biological abnormalities and allowed disappearance of symptoms; the patient was extubated after 46 hours, and outcome from intensive care unit at 65 hours.

A 51 year-old man with a renal cancer (pT3N0M0) consulted at the emergency department for persistent headache initiated a week before and recent vomiting. Physical examination and blood analyses were not remarkable. Cerebral magnetic resonance imaging demonstrated radiological signs of meningitis. The differential diagnosis of meningitis is discussed.

Plasmodium falciparum infection modifies the distribution of phospholipids on both sides of the erythrocyte-plasma membrane. We sought to understand the action of the parasite on both plasma and membrane phospholipids and their relation to parasite counts in the blood.We conducted this study from 1 February through 30 June 2007 in the Malaria Clinical Research Unit of the Libreville General Hospital Centre, measuring phospholipids in plasma and erythrocyte membranes of children affected by P. falciparum malaria and assessing their relation to blood parasites, lactates and hemoglobin.The study included 60 children. The mean blood parasite count was 1.07 x 105 per ml. Mean plasma phospholipids were 2.6+/-0.9 mmol/l and lactates 4.7+/-3.7 mmol/l. At the membrane level, we found 2.8+/-1.2 mmol/l of phospholipids per 106 red blood cells. Phospholipids in these two compartments were positively correlated with one another (r=0.392; p=0.023). Plasma phospholipids were also correlated positively with hemoglobin (r=0.36; p=0.032) and negatively with the number of parasites (r=0.442; p=0.002). The latter, in turn, was positively correlated with lactates (r=0.527; p=0.022) and negatively with membrane phospholipids (r=0.542; p=0.006). The mean hemoglobin level (8.9 g/dl) suggests permanent blood loss in these children, although they may be considered new malaria patients. The relations revealed here between membrane phospholipids, blood parasite counts, and lactate levels are due to the increased energy needs of erythrocytes, but also to the need to synthesize substances intended for cellular defense. P. falciparum thus leads to a decrease in plasma phospholipids, which could be estimated and correlated with blood parasites in a study with a wider range of parasite counts.

The multitude of criteria used to assess fetal distress and the subjective character of the Apgar score led us to compare the information it provides with that from measurements of lactate and two principal antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx). We measured plasma lactates, SOD, and GPX from the umbilical cord blood of live-born children whose mothers had had at least three prenatal consultations. The correlation of these measurements with the 5-minute Apgar score was tested with the Spearman correlation coefficient. Lactate levels were correlated with the baby's blood glucose (r=0.212; p=0.0084), and GPx activity (r=0.179; p=0.0061), the Apgar score (r=0.258; p=0.001) and the mother's blood glucose (r=0.167; p=0.035). GPx was correlated not only with the lactate level but also with birth weight (r=0.205; p=0.000) and height (r=0.316; p=0.0056), while SOD was correlated only with the mother's blood glucose (r=0.161; p=0.046). In multivariate analysis, followed by stepwise analysis, lactate was the main variable associated with the Apgar score. It thus seems better able to replace the Apgar score than the antioxidant enzyme levels. GPx was higher in children of high birth weight and may make them better able to combat the free radicals due to anoxia or hypoxia.

International audience; In most cases, differentiating viral from bacterial meningitis is relatively easy, based on clinical examination, CSF appearance and results of CSF examination (cytology, biochemistry and Gram stain). However, in about 20% of cases, this diagnosis may be difficult. For such cases, additional non-microbiological tests may be helpful. CSF lactate level is a good predictor of bacterial meningitis for values greater than 3.5 mmol/l. Serum procalcitonin is effective to discriminate between bacterial and viral meningitis, using a threshold between 1 and 2 ng/ml, although this parameter may fail in individual situations. Accurate diagnosis scores or models have been validated and may be used in routine clinical practice, especially in emergency rooms, both for adults and children to help identify patients with a very low probability of bacterial meningitis in whom antibiotic may thus be avoided.

The aim of this work was i) to analyse physiological and muscle characteristics (determinedfrom muscle biopsies) in trained lightweight oarsmen, ii) to propose a non-invasive method to estimatelactate accumulation in the organism (QTLS) using the blood lactate recovery kinetics in response to anall-out exercise on rowing ergometer and iii) to explore the influence of muscle characteristics andlactate exchange and removal abilities on the anaerobic capacity of our subjects determined from themeasurement of the maximal accumulated oxygen deficit (MAOD).Firstly, the studied oarsmen displayed an elevated muscle - body mass ratio and their muscleand physiological characteristics were typical of those of elite endurance athletes.Secondly, we showed that QTLS was positively correlated with MAOD. This relationshipsupports our hypothesis and reinforces the interest of our method to estimate QTLS.Finally, the results demonstrated that MAOD was positively correlated with the lactate removalability. This latter was also positively correlated with the capillary density and the muscle content ofMCT4, a protein involved in the cotransport of lactate and proton across the sarcolemma, Ce travail avait pour objectif i) d’analyser les caractéristiques physiologiques et musculaires(déterminées d’après des biopsies) de rameurs poids légers entraînés, ii) de proposer une méthode de153calcul pour estimer de façon non-invasive la quantité de lactate accumulé dans l’organisme (QTLS) au cours d’un exercice épuisant sur ergomètre aviron d’après la modélisation de la cinétique lactique pendant la récupération et iii) d’explorer l’influence des caractéristiques musculaires, et de l’aptitude à échanger et à éliminer le lactate sur la capacité anaérobie des rameurs appréciée par la mesure du déficit maximal d’O2 cumulé (DMOC).Premièrement, les rameurs étudiés possédaient un rapport masse musculaire - masse corporelle élevé et leurs paramètres physiologiques et musculaires étaient caractéristiques des athlètes spécialisées en endurance.Dans un deuxième temps, nous avons démontré que QTLS était corrélé positivement à DMOC.Cette relation supporte notre hypothèse et confirme la cohérence de la méthode proposée pour calculer QTLS.Dans une dernière étude, les résultats ont démontré que DMOC était corrélée positivement à l’aptitude à éliminer le lactate. Cette dernière était également significativement corrélée à la densité capillaire et au contenu musculaire en MCT4, une protéine impliquée dans le cotransport lactate-proton à travers le sarcolemme.

Les chiens de la gendarmerie sont formés pour réaliser un certain nombre d exercices très différents. Au cours de leur formation ou lors de leur travail sur le terrain, il arrive que certains d entre eux développent une intolérance à l effort. Ils doivent alors être réformés. Après une présentation sur la formation des chiens au Centre National d Instruction Cynophile de la Gendarmerie de Gramat et un état des lieux des connaissances actuelles sur la physiologie de l'effort et les animaux de sports, ce travail se penche sur l'entraînement d un groupe de 17 chiens. Ce groupe a été formé à la spécialité piste-défense pendant un stage de 3 mois. Un effort standard a été mis au point et réalisé au début et à la fin de cette période. A chaque fois, différents paramètres plasmatiques ont été évalué : les protéines totales, l'hématocrite, les lactates, la créatinine, et la créatine kinase. Aucun des chiens du groupe n a présenté d insuffisance à l'effort. Nous avons remarqué que l'hématocrite et les protéines totales ne varient pas comme ce qui est majoritairement rapporté dans la littérature. Pour la plupart des chiens, les variations des autres paramètres ne sont pas significatives. L'effort demandé ici est un effort sous-maximal. L'effet anticipation avant le footing et l'effet blouse-blanche sont importants à considérer. Il serait intéressant de refaire des tests pour un autre type d effort et sur d autres paramètres.

Mitochondrial encephalomyopathy lactic acidosis and stoke-like episodes (MELAS) is a rare neurodegenerative disease caused by mutations of mitochondrial DNA.We report the case of a 12-year-old child with MELAS syndrome who presented with recurrent migraine-like headache and sudden blindness suggesting stroke-like episodes. Furthermore, he developed progressive muscular impairment with bilateral hearing loss. Serum lactate and pyruvate levels were elevated and the muscle biopsy showed an aspect of red-ragged fibers with Gomori trichrome. Brain imaging showed calcifications of basal ganglia on the CT scan and a parieto-occipital high signal on diffusion-weighted MRI. A genetic analysis was not performed but the presence of hearing loss in the patient's mother was suggestive of maternal transmission. Stroke-like episodes in the form of migraine-like headache and blindness were the patient's major complaint and did not improve despite analgesic drugs. After oral administration of l-arginine at the dose of 0.4mg/kg per day, stroke-like symptoms totally and rapidly disappeared.The efficiency of l-arginine in stroke-like episodes was initially reported then confirmed in a controlled study. The pathophysiology of stoke-like episodes and the mechanisms underlying the action of l-arginine are discussed.

Intrapartum asphyxia is increased in several situations such as intrauterine growth retardation, preterm labor, postdate pregnancy or maternal diabetes. In all these cases, fetal heart rate monitoring should be preferred to intermittent auscultation. Fetal scalp blood pH or lactates can be used to identify fetuses at risk of intrapartum asphyxia. However, fetal scalp blood sampling should not delay delivery in case of severe abnormal fetal heart rate as fetal asphyxia could occur rapidly in theses high-risk pregnancies. Data is insufficient to recommend fetal pulse oximetry or ECG analysis. Research should be undertaken to evaluate their performance in these situations.

Fragile X syndrome is associated with expansion of a CGG triplet repeat in the FMR1 gene, which abolishes production of the FMRP protein. This abnormality is expressed as a number of neuro-endocrine disorders (the adrenal axis, macroorchidism) and the emergence of significant behavioural stress. Here, we report on the hormonal status of a young adult with fragile X syndrome, with a focus on catecholamine and cortisol changes during a submaximal treadmill test. The patient showed abnormally high epinephrine and norepinephrine concentrations. During a submaximal incremental test, cortisol levels were higher than the laboratory reference range. Although the submaximal incremental test has a significant “stressful” effect, this young adult was able to complete the entire protocol without any maladaptive behaviour or withdrawal.

This review reports recent observations concerning specificities of the cellular energy metabolism in cerebral tissues that highlight on characteristics of that of glial tumours, such as the association of metabolic alterations aggressiveness of these tumours. Compared to normal cerebral tissue, glial tissue exhibits both a relative independence towards oxygen and substrate furnitures and thus vascularization, as well as the metabolic co-operation of neurons and glial cells within the tumour. Occurrence of a Warburg effect could explain such metabolic autonomy that might be associated to genetic changes observed in gliomas. Characteristics of the glycolytic metabolism within glioma tissue therefore may be novel land therapeutic approaches for the treatment of these tumours.

Ethylene glycol is broken down to three main organic acids: glycolic acid, glyoxylic acid and oxalic acid which cause severe metabolic acidosis. Effect of these three acids on lactate assays was evaluated in five blood gas analysers and two clinical chemistry analysers. For all systems, no influence of oxalic acid on lactate results could be demonstrated. No interference of glycolic acid could be observed on lactate assay performed with Rapid Lab 1265 (R: 104,9 +/- 12,1%), Vitros 950 (R: 105,7 +/- 5,3 %) and Architect ci8200 (R: 104,9 +/- 4,7%), but on the contrary, CCX 4, OMNI S, ABL 725 and 825 demonstrated a concentration-dependent interference. No interference of glyoxylic acid could be observed with Vitros 950, but a positive interference could be observed with ABL 725 and 825, OMNI S, CCX4 and Architect ci8200 A linear relationship between apparent lactate concentration found with ABL 725 and 825, OMNI S, CCX 4, and glyoxylic acid could be observed (0,94r0,99), a weaker interference being observed with Rapid Lab 1265 and Architect ci 8200. Our results demonstrated that in case of ethylene glycol poisoning, cautious interpretation of lactate assay should be done, since wrong results of lactacidemia could lead to misdiagnostic and delay patient treatment.

From 73 normal pregnancies of gestational age between 17 and 41 weeks of gestation (WG), the concentrations of glucose, pyruvate and lactate, free fatty acids, ketone bodies (aceto-acetate and beta-hydroxybutyrate) and cholesterol were assessed on maternal venous blood (MVB) and umbilical venous blood (UVB), sampled by cordocentesis. The objective of this work was to study feto-maternal metabolism, as well as nutritional exchange between maternal blood and fetal blood during the second and third trimesters of pregnancy. Maternal and fetal glycemias, as well as maternal-fetal glucose concentration gradient, were found stable during the studied gestational period; maternal glucose is always higher than fetal glucose, with a mean concentration delta of 0.69+/-0.34 mmol/L. Maternal lactate level (1.26+/-0.38 mmol/L) is lower than fetal lactate level (1.48+/-0.46 mmol/L), whereas maternal blood pyruvate concentration (0.042+/-0.020 mmol/L) is higher than fetal blood pyruvate concentration (0.025+/-0.010 mmol/L). Consequently, mean lactate / pyruvate ratio is found twice lower in maternal blood (31.77+/-9.89) than in fetal blood (64.10+/-17.12). Free fatty acids concentration is approximately three times higher in maternal blood than in fetal blood (respectively 0.435+/-0.247 mmol/L and 0.125+/-0.046 mmol/L). Maternal venous aceto-acetate (0.051+/-0.042 mmol/L) and beta-hydroxybutyrate (0.232+/-0.270 mmol/L) concentrations are significantly lower than those in UVB (respectively 0.111+/-0.058 and 0.324+/-0.246 mmol/L) and the beta-hydroxybutyrate/aceto-acetate ratio is on average 1.7 times higher in MVB (4.75+/-2.5) than in UVB (2.82+/-1.18). Cholesterol concentration is significantly higher in maternal blood (6.26+/-1.40 mmol/L) than in fetal blood (1.66+/-0.34 mmol/L). Our results show the characteristics of oxidative metabolism of the fetus compared with that of the adult. Blood concentration in energy substrates, measured with glucose and free fatty acids levels, is low in UVB and suggests increased energy needs of the growing fetus. Mean high concentrations in aceto-acetate and beta-hydroxybutyrate in UVB, indicate probably fetal ketogenesis. UVB low cholesterolemia suggests high cholesterol consumption in the fetal compartment for cellular membrane synthesis and steroid biosynthesis.

To determine the accuracy of cardiopulmonary exercise-testing (CPET) in detecting exercise-induced pulmonary hypertension.CPET plays a key role in the investigation of exertional breathlessness. Exercise-induced pulmonary hypertension has been recently demonstrated to be a cause of exertional dyspnea. However, the features of CPET associated with the condition are still unknown.We prospectively studied CPET and exercise echo-cardiography characteristics in 39 patients complaining of exertional breathlessness. Patients could be divided into 3 groups as follows: 1) control subjects having normal pulmonary arterial pressure at rest [pulmonary arterial systolic pressure35 mmHg] and at peak exercise [pulmonary arterial systolic pressure45 mmHg]; 2) patients having exercise-induced PH; 3) patients having resting PH. Results from CPET have been analyzed within each group.Patients developing exercise-induced PH revealed an increased VD/VT ratio and CO2 gradient (P[a-ET]CO2) at peak exercise compared to controls (VD/VT at 0.38 +/- 0.1 vs 0.29 +/- 0.11 and P[a-ET]CO2 at 4,6 +/- 3,1 vs 1 +/- 3,8 mmHg). VD/VT and P[a-ET]CO2 were increased in patients with resting PH. A VD/VT ratio at peak exercise higher than 0.34 was 72.7% sensitive and 71% specific in predicting exercise-induced PH. Positive and negative predictive values were 72.7% and 70.1% respectively.Patients with exercise-induced PH did not decrease or may increase dead space during exercise. Therefore CPET may be a useful tool in selecting patients who need to undergo further exercise haemodynamic investigations.

Intra-uterine growth retardation (IUGR) is a frequent pathology in obstetrics characterized by high heterogeneity. Fetal smallness is sometimes constitutional, but can also be accompanied by fetal distress and vital risks for the infant. In 35 pregnancies complicated by IUGR of different etiologies, we measured on fetal blood obtained by cordocentesis, biochemical variables characteristic of the fetuses' respiratory and metabolic status. The aim of the study was to identify the discriminative biological alterations, related to growth retardation and fetal distress.The studied population includes 27 cases of severe IUGR, of gestational age 30,2+/-4,6 weeks of gestation (WG) (divided into 20 cases of isolated IUGR and 7 cases of IUGR associated with malformative syndrome), as well as 8 cases of moderate IUGR, of gestational age 26+/-4,5 WG; all fetuses had normal karyotypes. A group of 73 normal fetuses, of gestational age 26,3+/-5,7 WG, constituted a reference population. PH, pCO(2), bicarbonate concentration, pO(2) and SaO(2), as well as glucose, pyruvate, lactate, free fatty acids, aceto-acetate, beta-hydroxybutyrate and cholesterol concentrations were measured on umbilical venous blood (UVB).In case of severe but isolated growth retardation, UVB analysis showed the frequency of acid-base and gasometric disturbances: acidemia and hypoxemia (65% of cases), hypercapnia (60% of cases). Metabolic abnormalities were shown: decrease in glycemia (35% of cases), increase in pyruvatemia and lactatemia (40% of cases), increased free fatty acids serum concentration; a diminution of umbilical venous cholesterol level, the most frequent abnormality, can be seen in 70% of fetuses. In case of severe IUGR associated with malformative syndrome, UVB acid-base and metabolic changes were rarely seen; however, UVB cholesterol level is low in some cases. In case of growth retardation classified as moderate, modifications are relatively not frequent and essentially gasometric.In about 60% of cases of severe and isolated IUGR, there is a risk of fetal distress, related to an alteration of the transplacental transfer of respiratory gases and nutritional substrates; chronic fetal malnutrition can be involved, with an impact on the growth of the fetus. In case of IUGR associated with malformative syndrome, fetal smallness is probably a result of intrinsic fetal damage, without nutritional origin.

The tremendous progress achieved during the last few years with the use of highly active antiretroviral therapy in suppressing HIV replication together with improvements in immunity have been tempered by a growing number of new adverse effects. Mitochondrial toxicity is one aspect of these long-term toxicities of antiretroviral drugs, with the role of nucleoside analogs particularly underlined. Some cases of impaired mitochondrial function have been clearly identified, such as pancreatitis due to didanosine, neuropathy due to zalcitabine, myopathy due to zidovudine, and lactic acidosis due to stavudine. These mitochondrial toxicities can affect several organs, presenting different patterns of symptoms: from asymptomatic to states with few symptoms despite huge metabolic abnormalities whose prognosis is immediately life-threatening. Beyond the inhibition of DNA polymerase gamma using nucleoside analogs, responsible for decreasing mitochondrial DNA in certain targeted organs, it appears that several physiopathologic mechanisms interact to explain this observed toxicity, HIV itself plays a role, and the underlying genetic pool needs to be better identified. Such cases mean that, it is imperative to avoid cumulated toxicities caused by associated treatments. With serious cases, or persistent symptoms despite discontinuing the nucleoside analogs responsible for such toxicity, one must propose vitamins, mitochondrial co-factors, or anti-oxidants. However, the future lies in the use of potent, less toxic nucleoside analogs, and in developing compounds belonging to other classes of antiretrovirals.

MR spectroscopy (MRS) is a technique used to study a few metabolites in the brain or tumors in situ. This technique can provide information on tumor histological type and grade, and is helpful to identify tumor-like lesions, particularly abscesses. MRS can be used for treatment monitoring.

HIV-positive persons requiring a highly active antiretroviral therapy containing one or more nucleosidic reverse transcriptase inhibitors associated with or without protease inhibitors are exposed to metabolic side effects among which lipodystrophy and hyperlactemia, defined by blood lactates higher than 2,25 mmol/L. Hyperlactatemia had to be differentiated from lactic acidosis of type B (without hypoxemia, lactates higher than 5 mmol/L and arterial pH lower than 7,3), a rare but potentially fatal complication by multi-visceral failure. The accused INRT induce mitochondrial toxicity by inhibition of DNA gamma polymerase and deterioration of its DNA. Our exploratory study, troop of 282 patients, identified age and stavudine like statistically associated, which has occurred of this metabolic anomaly. The patients having profited of a therapeutic change with the profit from drugs minus hyperlactatogenic presented an obvious clinical and biological improvement; whereas similar switch of therapy occurred for the lipodystrophic patients presented any clinical improvement. Nevertheless, biological parameters (blood lactates, triglycerides, total cholesterol and LDL-cholesterol) were significantly decreased after this therapeutic switch occurred on the lipodystrophic patients. In conclusion, the measurement of the following biological parameters: glycemia, lactatemia, triglycerides, total cholesterol and LDL-cholesterol at patient VIH, in a simple and rigorous pre-analytical and analytical context, appears to us justified in the monitoring of metabolic disorders in treated HIV patients by INRT and/or IP.

To compare two techniques of lactate measurements in cord blood: either by electrochemical strip method with Lactate Pro of KDK in the umbilical artery alone (series 1) or by enzymatic method with Rapid lab Analyzer of Bayer in the two vessels (series 2) with acid base balance being also determined.Series 1 included 353 neonates with a mean gestational age of 37 (+/- 3.6) weeks and series 2 included 410 newborns with a mean gestational age of 38 (+/- 3.1) weeks.Data was presented as mean and SD. In the first series mean umbilical artery lactate concentration was 3.71 (+/- 1.81) mmol/l. In the second series mean umbilical artery blood gas and lactate levels were as follows: pH = 7.25 (+/- 0.9), pCO2 = 6.55 (+/- 1.39) kPa; BD = 6.61 (+/- 3.33) mmol/l, lactate 3.92 (+/- 1.81) mmol/l. The 3rd percentile of pH was 7.05 whereas the 97th percentile of lactate was 7.54 mmol/l. There was a close correlation between lactate and pH, and lactate and BD. Lactate concentration was higher in case of instrumental delivery compared to spontaneous one: 4.65 versus 3.76 mmol/l (p = 0.0001, Student test). No perfect correlation was found between lactate level and neonatal outcome but there was not a significant number of neonates with immediate complication.Lactate measurements obtained with single use strip method are valuable and easy to perform.

Ce travail a pour objectif d’étudier les adaptations physiologiques et biomécaniques au cours desenchaînements natation-cyclisme et cyclisme-course à pied d’un triathlon. Dans ce contexte, plusieurs études ontété réalisées :La première étude compare l’influence d’un 750 m de natation sollicitant soit les bras, soit les jambes,soit les bras et les jambes sur la dépense énergétique lors d’un exercice subséquent de 15 min de cyclisme. Leprincipal résultat montre que la sollicitation préalable des bras uniquement n’entraîne aucune variationsignificative des paramètres physiologiques mesurés en cyclisme comparativement à une sollicitation préalabledes bras et des jambes.La deuxième et la troisième étude s’intéressent à l’influence d’une diminution de l’intensité relative dela nage au cours d’un 750 m, soit par le port d’une combinaison (étude 2), soit grâce au drafting (étude 3) surl’adaptation physiologique en cyclisme. Les résultats montrent d’une part que le port de combinaison permetd’améliorer le rendement mécanique du cyclisme de 12%, et d’autre part que les effets combinés du port decombinaison et du drafting entraînent une augmentation supplémentaire du rendement de 4,8%.La quatrième étude a pour objectif d’analyser l’influence de la cadence de pédalage sur l’adaptationphysiologique lors d’un enchaînement natation-cyclisme. Le principal résultat indique que la dépenseénergétique en cyclisme est significativement inférieure lors d’un enchaînement natation-cyclisme (1500m-30min) réalisé à une cadence proche de la cadence énergétiquement optimale (75 rév.min-1) comparativement àune cadence proche de la cadence classiquement adoptée par les triathlètes en compétition (95 rév.min-1). Cesrésultats soulignent l’influence d’une épreuve préalable de natation de courte distance sur la dépense énergétiqueen cyclisme. Des travaux ultérieurs intégrant une épreuve de course à pied seraient nécessaires afin d’analyserces effets au cours d’un triathlon entier.L’objectif de notre second travail lié à l’enchaînement cyclisme-course à pied était d’étudier, les critères quidéterminent le choix de la cadence de pédalage et les conséquences de ce choix sur a) l’adaptation en cyclismeavec la durée de l’exercice et b) l’adaptation en course à pied (Càp) lors d’un enchaînement cyclisme-course àpied. Notre principale expérimentation a étudié l’influence d’une épreuve de cyclisme réalisée à 3 cadencesdifférentes (CL = 81 rpm ; CEO = 72 rpm ; 90 rpm = optimum mécanique théorique) sur l’adaptation lors de laCàp subséquente. Le principal résultat met en évidence que le choix d’une CEO induit une réduction de VO2lors du cyclisme (30-min) et de la Càp (15-min) comparativement aux autres conditions expérimentales.Suite à ces résultats, l’objectif de la troisième étude est d’analyser l’effet de 3 cadences différentes(60, 80 et 100 rpm) en cyclisme (20-min) sur la performance en Càp (3000 m). Le principal résultat nemontre aucune influence significative de la cadence sur la performance. Cependant, un effet différencié de lacadence est observé sur les réponses ventilatoires et cinématiques lors de la Càp subséquente.Nos résultats suggèrent que le choix de la cadence en triathlon peut influencer l’adaptationphysiologique du sujet lors de l’enchaînement cyclisme-Càp. Dans un contexte proche des contraintes del’activité, des études ultérieures sont nécessaires pour évaluer la relation entre le choix d’une cadence depédalage particulière et la performance en Càp.

Irrigation of povidone iodine considered as a safe and effective procedure, is frequently used for deep infections. We report a case of intoxication by iodine in a man of 68-year-old after subcutaneous irrigations of Betadine at a concentration of 20% for a subcutaneous infection of the thigh. Abnormalities of cardiac conduction, lactic acidosis, acute renal failure, hypocalcaemia and thyroid dysfunction were the manifestations of the intoxication confirmed by a very high level of total blood iodine and urine iodine.

Authors illustrate the evolution of the physiological profile of gymnasts over the past 40 years. Gymnasts are demonstrating increased anaerobic power. Maximal power output measured by the Wingate test in high level male gymnasts is currently between 12 and 14 W x kg(-1). Female gymnasts show maximal power between 10 and 12 W x kg(-1). In spite of an increase in the number of training hours, they have a low aerobic aptitude. It is still adequate and sufficient for their practice. Maximal heart rate values measured during gymnastic exercises have mirrored technical and acrobatic demands of increasing difficulty. Currently, exercise heart rates exceed 190 beat x min(-1) as compared to 135 to 151 beat x min(-1) in the seventies. Measurement of higher blood lactate values suggests that anaerobic glycolysis has increased in importance. Glycolytic contributions differ between apparatuses. Data from energy cost studies demonstrate that gymnastics energy demands are greater now than in the seventies.

The authors report four cases of patients presenting with hyperlactatemia following renal transplantation. The post-transplantation course of three patients who underwent renal transplantation was complicated by occult haemorrhage. Excessive blood loss was not evident, the patients were haemodynamically stable and their blood pressure, pulse rare and filling pressure (central venous pressure) were unremarkable. Late examinations revealed an early increase in arterial lactate concentrations a non-aniograp acidosis or lactic acidaemia occurred. Surgical decompression was carried on in all patients. An increase in the intraabdominal pressure might have caused renal impairment in the absence of haemodynamic disturbance, and retroperitoneal haematoma a change in the distribution of intrarenal blood flow. Another patient developed a partial renal venous thrombosis associated with hyperlactatemia. During this re-operation, a renal lactate production was measured. The renal cortex is a site of lactate clearance. Impaired renal perfusion should result in decreased lactate clearance and when the kidney is hypoperfused a lactate production was occur. In the absence of any signs of clinical shock, patient at risk of retroperitoneal haematoma or presenting with oliguria should benefit from lactate measurements, which could help diagnosing severe hypoperfusion of the graft.

Infantile anorexia is usually considered as a psychogenic disorder with benign prognosis. However, unusually severe characteristics of infantile anorexia, seen in the south of the island, seem to us in favor of a new metabolic etiology.Among 38 known cases, we retrospectively studied the best documented observations of 24 children admitted over the last 25 years to our institution.The sex ratio was ten females and 14 males. Twenty-three of the 24 infants lived in formerly isolated localities of the island where other hereditary diseases have been observed with an unusually high frequency. The family pedigrees favoured an autosomal recessive heredity. Severe anorexia, accompanied by irrepressible vomiting (91%), appeared at the age of 8.5 months +/- 3.5. Parenteral (54.2%) or enteral (54.2%) feeding was necessary but did not always avoid death, which occurred in 45.8% of the cases at the age of 24 months +/- 3.5. All of the children which survived had neurological disorders (pyramidal syndrome, ataxia, laryngeal palsy, mental retardation, seizures) which occurred sometimes at an early stage. The investigations did not allow the identification of any known cause.The elevated level of lactic acid in the cerebral spinal fluid seemed to indicate a possible mitochondrial disorder, eventually a mutation of an autosomal gene of the pyruvate dehydrogenase complex because of the normal lactate/pyruvate ratio, but enzymatic activities were normal. The cerebral MRI showed features of leukodystrophy. On the other hand, the elevated level of plasma serotonin seemed to indicate a disorder of the serotonin metabolism, for which an animal model exists.We propose to name this new syndrome by the acronym 'RAVINE' which associates Reunion, Anorexia, Vomiting which is Irrepressible, and Neurological signs. Linkage study might allow the localization and isolation of a gene and allow one to start understanding the biological mechanism which we suspect to be an hereditary neurobiological eating disorder.