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The Haldane M-value is the ratio of half-saturation pressures for O2 and CO (PO2/PCO) and is a key value of physiological and pathological models exploring CO metabolism or exposure to CO. Nevertheless, the M-values obtained from different studies and different species appear to be inconsistent. A better estimation of M-values and a consideration of interspecies variation will ensure the accuracy of CO study results and allow reliable models to be constructed. We performed a systematic review and meta-analysis in order to determine and compare M-values according to species and experimental conditions. We used electronic libraries (PubMed/Embase/JSTORE) from 1895 to January 2016. For each article, we collected the following parameters: species, age, temperature, pH, atmospheric pressure, concentration of 2,3-diphosphoglycerate (2,3-DPG) or methemoglobin, and type of hemoglobin. The systematic review found 25 articles addressing the M constant, including 135 with individual data and 51 with mean values concerning mammals, laboratory animals, fish, fetal hemoglobin and invertebrates. M-values at a physiological temperature and pH were assessed only for adult (137 [119–153]) and fetal (135 [112–168]) sheep, dogs (215 [193–218]), mice (194 [118–278]) and rats (191 [177–200]). A correlation between M-values and temperature was confirmed for sheep and horses. A correlation between M-values and pH could not be inferred because there was a lack of data. M-values varied according to species. Only the influence of temperature was confirmed. A formal measurement of the M constant in the given experimental conditions should be performed for each animal model study of CO. Further homogeneous studies are necessary to compare the M-values of different animals.

Mucormycosis is an opportunistic fungal infection involving among others the paranasal sinuses, nasal fossa and brain parenchyma. Mucor can invade the brain parenchyma by either contiguous spread from the paranasal sinuses or through vascular invasion. We report a case of fatal rhino-cerebral mucormycosis in whom cytotoxic edema at magnetic resonance diffusion-weighted imaging was symmetrically restricted to both neocortical and paleocortical primary areas of olfactory projection at earliest phase of the disease process. Shortly later tissue damage extended into the whole brain. This undescribed observation raised the hypothesis of preferential way of brain invasion by Mucor through the olfactory tract.

Resume De nouveaux medicaments anti-epileptiques sont apparus ces dernieres annees. Les anti-epileptiques demeurent des substances frequemment utilisees lors des tentatives de suicide medicamenteuses. Les donnees recueillies par les centres antipoison nord-americains indiquent que la mortalite et la morbidite demeurent elevees avec les molecules anti-epileptiques de la generation anterieure, en particulier avec l’acide valproique. L’objectif de cette courte revue est de presenter le profil de securite de sept anti-epileptiques recents : topiramate, vigabatrin, tiagabine, gabapentine, levetiracetam, felbamate, lamotrigine et oxcarbazepine. Il decoule des observations isolees ou des rares series publiees que les intoxications aigues par les anti-epileptiques de nouvelles generations s’accompagnent d’une mortalite et d’une morbidite extremement basses. Comme prevu, une depression du systeme nerveux central de courte duree a ete frequemment observee. Cependant, seul un faible nombre de patients a du beneficier d’une ventilation artificielle. Des crises d’epilepsie sont occasionnellement decrites. Une toxicite cardiovasculaire significative n’a ete rapportee a ce jour que dans quelques observations. Le traitement de ces intoxications est essentiellement symptomatique.

To describe a case of reversible visual loss after a neurosurgical intervention and to discuss the role of the prone position as a potential risk factor.A 63-year-old woman without significant medical previous history underwent elective resection of a left parieto-occipital meningioma. Preoperatively, the patient presented a right homonymous lower quadranopsia. The surgical procedure was not complicated. The patient was positioned in prone with a mild inclination of the table in reverse Trendelenburg position. The head was maintained in a Mayfield skull clamp, and ocular compression was excluded. There was no significant hypotension, hemodilution or vasopressors infusion during the procedure. Immediately after recovery from anesthesia, the patient experienced total blindness and flash visual evoked potentials confirmed the absence of retinal, primary or late occipital activities. A progressive, but finally complete recovery started after 24 hours.This case illustrates the individual risk for visual injury after the prone position during some neurosurgical interventions.

To avoid accidental poisoning, pesticides must be handled according to prescribed rules. Furthermore, the exact composition of the pesticide formulation should be known. Cases of acute poisoning usually occur by ingestion and less frequently by the other routes. Symptoms may appear immediately but sometimes they can appear later and/or be more prolonged giving rise to delayed death and/or delayed morbidity. Acute poisoning by raticides and by organophosphate insecticides should deserve all our attention. Poisoning by herbicides containing chlorate salts, oxidative phosphorylation uncouplers or bipyridilium derivatives may be particularly dangerous. The ingestion of Paraquat, in particular, which is a veritable lesional poison, could be beyond all therapeutic resources. Language: en

The treatment of acute or chronic pain of variable intensity and origin, is efficiently achieved by the association of paracetamol and codeine. At a dose of 1000 mg paracetamol and 60 mg of codeine, this association is considered one of the most efficient as compared to other analgesics of level II in the OMS classification, like tramadol.

A particularly severe case of Guillain-Barré syndrome occurring during pregnancy is reported. The therapeutic approach including plasmapheresis, ventilation, analgesia, sedation, metabolic requirements and heparin therapy is discussed with the consequences on foetal development and the early days of life.

Presents a case study of a massive oral exposure to hexavalent chromium in which there was demonstrable toxic effects seen on the proximal renal tubule that remained limited. Initial treatment of the medical condition; Main manifestations of hexavalent chromium toxicity; Results of the early administration of ascorbic acid and N-acetylcysteine.

The ability of paracetamol to induce structural chromosome aberrations in human peripheral blood lymphocytes in vivo was evaluated in volunteers who had been administered a single oral dose of 3 g paracetamol, in patients who had received 2 g of propacetamol by intravenous infusion every 6 h for at least 7 days, and in self-poisoned patients who, for suicidal reasons, had ingested more than 15 g paracetamol. In addition to the in vivo observations, the effectiveness of paracetamol to interfere with fusorial microtubule polymerisation was assayed in vitro in order to detect a possible effect of paracetamol on the distribution of chromosomes during cell division. The negative results obtained in all those assays strongly suggest that paracetamol has no mutagenic properties in human. There was, indeed, no significant difference in the percentage of abnormal cells before and after application of paracetamol in volunteers (0.2% before ingestion of 3 g paracetamol, 0.12% after 24 h, 0.04% after 72 h and 0.04% after 168 h) and in patients (0.5% of abnormal cells before treatment versus 0.44% after intravenous infusion of a total of 28 g paracetamol). Moreover, the yield of abnormal cells was not modified in self-poisoned persons (0.24%), in spite of an important decrease in the mitotic index of the PHA stimulated lymphocytes. In the in vitro assay, no inhibition of microtubule polymerisation was detected with concentrations of 2.5, 5 and 10 mM paracetamol.

Acute exposure to toxic inhalants under occupational or accidental circumstances may lead to a large variety of clinical manifestations, some of them being particularly life-threatening. The chronic effects of acute exposure have not been fully characterized. In this chapter, toxic gases are classified according to the mechanism of injury, either as irritant or as asphyxiant, and their clinical manifestations following fume or smoke exposure are presented. The inhalation of ammonia vapors causes irritation of the eyes and respiratory tract. Bromine gas is very corrosive to the eyes, skin, and respiratory tract. Inhalation of iodine vapors may lead to irritation of the respiratory tract. Phosgene is a highly toxic gas, which is considered as an irritant to the skin, eyes, and respiratory tract. Ozone acts primarily as an irritant for the eyes, throat, and respiratory tract. Acute and chronic effects of carbon monoxide poisoning are due to tissue hypoxia. Cyanide exposure may produce death within minutes. Phosphine toxicity occurs either following ingestion or inhalation. Symptoms of chronic poisoning include anemia, bronchitis, gastro-intestinal and neurosensorial disturbances.

Cardiac arrhythmias and circulatory collapse account for the high mortality reported after severe chloroquine poisoning. We have recently observed a 17-year-old man who ingested an 8 g chloroquine overdose. Cardiac arrest occurred within 1 h. Cardiogenic shock was refractory to epinephrine, dopamine and molar sodium lactate. Amrinone, a bipyridine analog, was then successfully used to improve haemodynamic conditions.