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Introduction: In French Guiana, most snakebites are caused by crotalids, with the main signs being tissue damage and bleeding due to venom-induced coagulopathy. Since December 2014 the Western Guia...

Dear Editor, We thank Drs Greene and Brandehoff for their interest in our article, but we are surprised that they consider a study comparing the kinetics of hemostasis in 84 patients envenomed main...

Background Coronavirus disease 2019 (COVID-19) has changed the practice of all health-care professionals. Determining the impact could prevent repercussions in future crisis. Objectives The objectives of the study were to assess the impact of the COVID-19 pandemic on dermatology residents’ professional practice, working conditions, academic training and mental health. Methods An online questionnaire was sent to all French dermatology residents. We compared the activity of residents working in areas heavily impacted by COVID-19 to others. Logistic multivariate regressions were done, using as outcome variables the negative impact of the COVID crisis on residents’ possibility to practice dermatology during the crisis, supervision, academic training and working more than 50 h/week. The last part of the questionnaire was the burnout questionnaire of Maslach. Results A total of 246 residents filled the questionnaire. Residents working in highly impacted COVID areas (odds ratio, OR 0.34 confidence interval, CI [0.18, 0.61], P ≤ 0.001), first-year postgraduate (PGY-1) residents (OR 0.46 CI [0.23, 0.91], P = 0.023) and those in private practice (OR 0.10 CI [0.01, 0.57], P = 0.032) were significantly less able to maintain dermatology activities. Worse supervision was significantly more frequent with non-PGY-1 residents (OR 3.24 CI [1.65, 6.65], P < 0.001). One hundred and eighty one residents claimed the pandemic to have a negative effect on their dermatology curriculum with no difference according to their regions’ affection by COVID-19. This was mostly attributed to the cancelation of courses and congresses. PGY-1 residents (OR 2.09 CI [1.09, 4.04], P = 0.029) and residents in highly affected areas (OR 1.79 CI [1.01, 3.18], P = 0.049) were more at risk of working above the maximal legal working time. None of the residents was free of burnout symptoms. Conclusion Dermatology residents have been highly affected by COVID-19. It might be important to have a more integrated healthcare system to fight times of crisis with the least repercussions on residents.

Summary The objective of this study was to explore whether ketamine prevents or exacerbates acute or post-traumatic stress disorders in military trauma patients. We conducted a retrospective study of a database from the French Military Health Service, including all soldiers surviving a war injury in Afghanistan (2010–2012). The diagnosis of post-traumatic stress disorder was made by a psychiatrist and patients were analysed according to the presence or absence of this condition. Analysis included the following covariables: age; sex; acute stress disorder; blast injury; associated fatality; brain injury; traumatic amputation; Glasgow coma scale; injury severity score; administered drugs; number of surgical procedures; physical, neurosensory or aesthetic sequelae; and the development chronic pain. Covariables related to post-traumatic and acute stress disorders with a p ≤ 0.10 were included in a multivariable logistic regression model. The data from 450 soldiers were identified; 399 survived, of which 274 were analysed. Among these, 98 (36%) suffered from post-traumatic stress disorder and 89 (32%) had received ketamine. Fifty-four patients (55%) in the post-traumatic stress disorder group received ketamine vs. 35 (20%) in the no PTSD group (p

Resume L’histoire de la ketamine commence dans les annees cinquante aux laboratoires Parke-Davis de Detroit. En 1956, Maddox synthetise la phencyclidine ou PCP. Domino etudie ses effets chez les animaux et en 1958, Greifenstein fait les premiers essais du Sernyl chez l’homme. Le Sernyl provoquait des troubles psychiques severes et prolonges. En raison de ses effets psychedeliques, il devint une drogue de rue sous le nom de « poussiere d’ange ». Calvin Stevens synthetisa la ketamine en 1962. Elle fut etudiee chez l’homme en 1964 par Domino et Corssen qui decrivirent l’anesthesie dissociative. Elle fut brevetee en 1966 sous le nom de Ketalar et administree aux blesses de la guerre du Vietnam. Ses effets psychedeliques et l’arrivee du propofol la firent tomber en desuetude. Cependant, la decouverte du recepteur NMDA et son inhibition non competitive par la ketamine revolutionnerent la pathophysiologie de l’hyperalgesie et du fonctionnement mental. Au debut des annees 1990, la decouverte de l’hyperalgesie induite par les opioides provoqua un changement de paradigme dans la prise en charge de la douleur et le retour de la ketamine comme medicament anti-hyperalgesique. Elle est aujourd’hui sous le feu des projecteurs dans le domaine de la depression resistante au traitement et a ete proposee comme antidepresseur d’action rapide chez les patients a haut risque suicidaire.

Hemostasis disorders are one of the major clinical conditions of snakebites and are because of mechanisms which may disrupt vessels, platelets, clotting factors and fibrinolysis. Thromboelastography (TEG) could help to understand these effects in the clinical practice. A retrospective study reports a series of patients presenting a snakebite-related coagulopathy, treated with antivenom and monitored with conventional tests and TEG in a French military treatment facility (Republic of Djibouti, East Africa) between August 2011 and September 2013. Conventional coagulation assays (platelets, prothrombin time, activated partial thromboplastin time, fibrinogen) and TEG measurements were taken on arrival and at various times during the first 72 h of hospitalization, at the discretion of the physician. The study included 14 patients (median age 28 years). Bleedings were present in five patients. All patients received antivenom. A coagulopathy was present in all patients and was detected by both conventional assays and TEG. None exhibited thrombocytopenia. Prothrombin time and fibrinogen remained abnormal for most of patients during the first 72 h. The TEG profiles of 11 patients (79%) showed incoagulability at admission (R-time > 60 min). TEG distinguished 10 patients with a generalized clotting factor deficiency and 4 patients with an isolated fibrinogen deficiency after an initial profile of incoagulability. Hyperfibrinolysis was evident for 12 patients (86%) after Hour 6. Snake envenomations in Djibouti involve a consumption coagulopathy in conjunction with delayed hyperfibrinolysis. TEG could improve medical management of the condition and assessment of additional therapeutics associated with the antivenom.

Resume La prevalence du burnout a longtemps ete sous-estimee notamment chez les professionnels de sante et particulierement dans le milieu de l’anesthesie-reanimation. Les facteurs de risque sont l’augmentation de la charge de travail, le manque d’autonomie decisionnelle, le travail de nuit et les conflits eventuels sur les lieux du travail et notamment au bloc operatoire. Le burnout decoule d’une augmentation des contraintes liees au travail tandis que les signes de reconnaissance sont absents. Il est caracterise par une serie de symptomes tels que la fatigue, la depression et le desinteret. Le college francais des anesthesistes a mis a disposition un numero vert qui donne un acces libre a une assistance psychologique pour les professionnels susceptibles de souffrir de burnout. Les professionnels souffrant de burnout doivent etre ecartes au moins transitoirement de leur activite professionnelle avant d’envisager une reprise progressive apres avoir beneficie d’un soutien adapte.

For more than 50 years, ketamine has proven to be a safe anesthetic drug with potent analgesic properties. The active enantiomer is S(+)‐ketamine. Ketamine is mostly metabolized in norketamine, an active metabolite. During “dissociative anesthesia”, sensory inputs may reach cortical receiving areas, but fail to be perceived in some association areas. Ketamine also enhances the descending inhibiting serotoninergic pathway and exerts antidepressive effects. Analgesic effects persist for plasma concentrations ten times lower than hypnotic concentrations. Activation of the (N‐Methyl‐D‐Aspartate [NMDA]) receptor plays a fundamental role in long‐term potentiation but also in hyperalgesia and opioid‐induced hyperalgesia. The antagonism of NMDA receptor is responsible for ketamine's more specific properties. Ketamine decreases the “wind up” phenomenon, and the antagonism is more important if the NMDA channel has been previously opened by the glutamate binding (“use dependence”). Experimentally, ketamine may promote neuronal apoptotic lesions but, in usual clinical practice, it does not induce neurotoxicity. The consequences of high doses, repeatedly administered, are not known. Cognitive disturbances are frequent in chronic users of ketamine, as well as frontal white matter abnormalities. Animal studies suggest that neurodegeneration is a potential long‐term risk of anesthetics in neonatal and young pediatric patients.

Resume Objectif Evaluer les facteurs lies au burnout en anesthesie–reanimation. Type d’etude Observationnelle prospective nationale. Materiels et methodes Questionnaire en ligne du 3 juin 2009 au 27 aout 2009 : Maslach Burnout Inventory (MBI), echelles Fast Alcohol Consumption Evaluation (FACE) et The Harvard National Depression Screening Day Scale (HANDS), questions evaluant sante, travail et vie personnelle. Resultats Au total, 1603 reponses : 1091 medecins anesthesistes (67,6 %), 241 reanimateurs (14,9 %), 204 infirmiers anesthesistes diplomes d’etat, interne (IADE) (12,6 %), urgentistes (2,8 %), cadres (0,9 %). CHU (47,3 %), CHG/CHR (16,1 %), prive (25,1 %), PSPH (4,4 %), hopitaux militaires (4,6 %). Repos de securite : prevu dans 69,2 % des cas. Accident apres une garde : 19,1 %. Depression : 38,7 %. Consommation de substances psychoactives : 10,6 %. Alcoolodependants : 10,6 %. Parmi eux, 62,3 % des individus etaient en burnout. Il existait un lien entre burnout et sommeil fragmente (p Conclusion Cette etude confirme l’existence d’une proportion elevee de burnout dans la plus importante cohorte de personnels d’anesthesie–reanimation decrite en France. Une meilleure connaissance des tenseurs par les equipes et les responsables institutionnels peut faciliter la prevention du syndrome.

L’heparinotherapie, largement utilisee pour le traitement des syndromes viperins il y a une trentaine d’annees, est desormais contre-indiquee a leur phase aigue, hemorragique. Nous rapportons un cas d’embolie pulmonaire, situation rare au decours des envenimations viperines. Par l’intermediaire de ce cas clinique, nous discutons les liens physiopathologiques entre envenimation et maladie thromboembolique d’une part et, d’autre part, la place de l’heparinotherapie prophylactique, non pas pendant la phase aigue, mais a son decours, lorsque le syndrome hemorragique a laisse la place a un syndrome inflammatoire, a une augmentation de la fibrinogenemie et a des plaquettes qui sont alors prothrombotiques.

Resume Le mediateur physiologique de la jonction neuromusculaire est l’acetylcholine, synthetisee grâce a la choline acetyltransferase, et hydrolysee par la cholinesterase. L’acetylcholine liberee par l’influx nerveux se fixe sur le recepteur nicotinique postsynaptique ; l’ouverture du recepteur-canal depolarise le sarcolemme, generant le potentiel d’action musculaire qui ouvre les canaux calciques voltage-dependants. L’augmentation de la concentration cytosolique de calcium declenche la contraction musculaire. Les recepteurs presynaptiques a l’acetylcholine jouent un role determinant dans la regulation de sa liberation, ainsi que diverses proteines des vesicules. La denervation entraine une sur-regulation des recepteurs, L’occupation des recepteurs par les curares inhibe la transmission neuromusculaire. La succinylcholine, curare depolarisant, est un agoniste de l’acetylcholine. Elle induit un bloc depolarisant, mais peut produire un bloc non depolarisant en cas d’utilisation prolongee ou de deficit en pseudocholinesterases. Les curares non depolarisants sont des antagonistes de l’acetylcholine, induisant un bloc par competition. Les maladies induisant des situations de sur-regulation des recepteurs exposent a des risques majeurs d’hyperkaliemie et d’arret cardiaque en cas d’utilisation de la succinylcholine. A l’inverse la destruction des recepteurs postsynaptiques ou le deficit en acetylcholinesterases exposent a des curarisations prolongees avec les curares non depolarisants. Le monitorage instrumental de la curarisation et la levee d’un bloc non depolarisant residuel par les anticholinesterases contribuent a la securite des patients en anesthesie-reanimation.

Resume Objectif Le concept de damage control recouvre une strategie de prise en charge du choc hemorragique centree sur une chirurgie de sauvetage minimaliste associee a une reanimation perioperatoire. L’objectif de cette revue est de faire le point sur les pratiques actuelles concernant la procedure de damage control . Acquisition des donnees References obtenues dans les revues generales recentes, les documents personnels et par recherche dans la banque de donnees Medline des articles de langue francaise et anglaise. Nous avons retenu l’ensemble des categories d’articles sur le theme. Synthese des donnees Le concept initialement chirurgical de damage control surgery , base sur le principe d’une laparotomie ecourtee et reprise apres une phase de reanimation, vient desormais s’inscrire dans un concept plus global de damage control resuscitation , qui insiste sur la prise en compte precoce de la triade letale (coagulopathie, hypothermie et acidose). La prevention de la coagulopathie est devenue l’enjeu prioritaire de la prise en charge. Les modalites de la reanimation initiale, lors de la phase dite damage control ground zero , ont ete redefinies : lutte contre l’hypothermie, techniques de controle du saignement, equilibre entre le concept d’hypotension permissive et l’emploi precoce de vasopresseurs. La strategie transfusionnelle a elle aussi evolue : apport precoce de plaquettes et de facteurs de la coagulation, emploi d’agents hemostatiques comme le facteur VII active, voire transfusion de sang total, definissent desormais le damage control hemostatique. De plus les progres des techniques chirurgicales et le developpement de l’embolisation ont mene a une extension des indications de cette strategie de prise en charge.

To the editor Ketamine has been used for more than 50 years, and its safety in anesthesia practice has been definitely established, but the recent PODCAST trial[1][1] confirmed that a single ketamine bolus is of no value for the management of postoperative pain.[2][2] Indeed, it has been recognized

Resume Les morsures de serpents sont un probleme meconnu de sante publique, qui concerne principalement l’Afrique sub-saharienne et l’Asie du Sud. En France, alors que la prevalence de ces morsures est faible, la mode des nouveaux animaux de compagnie expose au risque d’envenimations graves par des especes exotiques introduites sur le territoire. Le syndrome viperin principalement du aux crotales et aux viperes, associe troubles de l’hemostase et lesions locales (douleur, œdeme, necrose). Les troubles de l’hemostase sont lies a une coagulopathie de consommation induite par le venin (CCIV) a distinguer de la coagulation intravasculaire disseminee et se traduisent le plus souvent par des saignements locaux puis diffus. Les elapides sont responsables d’un syndrome cobraique, resultant de l’action de neurotoxines sur la plaque motrice et aboutissant a une paralysie respiratoire. D’autres syndromes sont possibles : atteinte circulatoire, insuffisance renale aigue, atteinte cardiotoxique ou myotoxique. En pratique, ces differents syndromes sont souvent associes, dans des tableaux polymorphes. L’envenimation ophidienne est une urgence absolue, necessitant parfois des gestes de reanimation sur le terrain (remplissage vasculaire, intubation oro-tracheale en sequence rapide, ventilation artificielle). L’evacuation hospitaliere doit etre systematique afin d’administrer l’immunotherapie antivenimeuse, seul traitement etiologique. Son indication peut etre guidee par l’utilisation de grade clinicobiologique. L’association a du plasma frais congele semble corriger plus rapidement la CCIV. En revanche, l’heparinotherapie est contre-indiquee a la phase aigue.

Resume Le traitement des etats de choc requiert frequemment un remplissage vasculaire. Le serum sale hypertonique est une alternative aux solutes classiques, cristalloides isotoniques et colloides. Le concept de remplissage vasculaire a faible volume s’est developpe au cours des 30 dernieres annees, essentiellement dans les domaines du choc hemorragique et de l’osmotherapie cerebrale. Plus recemment, le serum sale hypertonique a ete evalue dans d’autres types de choc : septiques et cardiogeniques. L’augmentation de la precharge, de l’inotropisme et l’amelioration de la microcirculation diminuent la defaillance hemodynamique. D’autres proprietes comme l’immunomodulation ou l’effet anti-œdemateux sont interessantes dans de nombreux types de chocs. Les donnees issues majoritairement de modeles animaux militent pour des essais cliniques dans differentes pathologies.

Fluid loading is the first step, necessary to care for severe sepsis. Two main classes of solutions are currently available: crystalloids and colloids. The concept of small volume resuscitation with hypertonic saline has emerged these last years in the care of traumatic haemorrhagic shock. The main benefits are the restoration of intravascular volume, improvement of cardiac output and improvement of regional circulations. Many experiments highlight modulation of immune and inflammatory cascades. We report the mechanisms of action of hypertonic saline based on experimental human and animal studies, which advocate its use in septic shock.

Various haemostasis disorders can occur following snakebite. Almost all ophidian species that are responsible for serious, even lethal, human envenomations are concerned. Venoms of these snakes are rich in proteins interfering with haemostasis, including many enzymes. These proteins can be classified in four groups according to their action. The haemorrhagins induce capillary permeability disorders. The proteins disturbing the primary haemostasis can activate as well as inhibit platelets: phospholipases A2, serine proteases and metalloproteinases, L-amino-acido-oxydases, phosphoesterases, disintegrins, C-type lectins, dendropeptin, agregoserpentin, thrombolectin. The proteins interfering with coagulation are separated into procoagulant proteases (prothrombin activator, thrombin-like enzymes, factor X and factor V activators) and anticoagulant proteases (factor IX and X inhibitors, protein C activator, anticoagulant phospholipases A2). The venom components acting on fibrinolysis are the fibrinolytic enzymes and the plasminogene activators. The clinical consequence of these mechanisms is a local as well as diffuse haemorrhagic syndrome. A hypofibrinogenemy, even an afibrinogenemy is frequently noted. Other haemostasis parameters are disturbed: PT collapse, a patient's ACT several times higher than the control and non-systematic thrombopenia. Ophidian venoms take part in many medical, diagnostic or therapeutic, applications in medicine. Currently, the antivenomous immunotherapy is the only efficient treatment in these haemorrhagic disorders.

Many snakes are able to quickly immobilize prey, thanks to their venom neurotoxins. Most of these snakes belong to families Elapidae or Hydrophidae but neurotoxins were also isolated from families Viperidae and Colubridae. Ophidian neurotoxins can be classified into several categories: neurotoxins which inhibit synaptic transmission (postsynaptic and presynaptic neurotoxins) and neurotoxins which facilitate it excessively (dendrotoxin and fasciculin). Their toxicity is dose-dependent, and venom effects are extremely fast. The clinical feature is a potentially fatal neurological syndrome, the so called cobraic syndrome. Because death by respiratory arrest may occur quickly with cobraic syndrome, immunotherapy is a true emergency, because toxins irreversible fixing makes immunotherapy effect uncertain after a few hours passed.

Resume L'envenimation par piqure de scorpion est peu etudiee chez des victimes en etat gravidique. Dans ce travail, l'effet du venin brut de Buthus occitanus tunetanus sur la parturition a ete etudie sur un modele experimental murin. Quatre lots de six rattes primigestes, toutes au 22e jour de la gestation, ont ete utilises. Les lots 1 et 2 ont recu une injection intraperitoneale de 500 μg/kg de venin brut de Buthus occitanus tunetanus ou d'une solution physiologique, et ont ete laisses jusqu'a la delivrance de tous les fœtus. Le temps ecoule a la delivrance du premier fœtus et celui separant celle du premier et du dernier ont ete alors mesures. Les deux autres lots ont ete anesthesies et artificiellement ventiles et utilises pour l'exploration electrophysiologique de la contractilite uterine apres une injection intraperitoneale de 500 μg/kg de venin brut ou d'une solution physiologique. Nos resultats ont montre une augmentation significative du temps ecoule a la delivrance du premier fœtus et celui du travail, et de l'activite contractile de l'uterus, chez les rattes envenimees comparees aux temoins. Ces signes sont communement observes en cas de dystocie dynamique. L'envenimation par piqure de Buthus occitanus tunetanus pourrait alors induire une dystocie dynamique en fin de gestation. Pour citer cet article : H. Ben Nasr et al., C. R. Biologies 330 (2007).

Snake bites are a major public health problem in the tropics but they have a low incidence in Europe and are responsible for few deaths each year. The incidence is higher in children than in adults but no difference in severity seems to be observed between children and adults. In France, snake envenomations are due mainly to Vipera aspis and Vipera berus. The clinical presentation is usually limited to a local syndrome with pain and local inflammatory edema, but systemic signs occur in 17% of cases. Clinical grading published by the Institut Pasteur in Paris helps to assess the severity of envenomation and to decide the use of antivenom. Every bitten patient must be transferred in a hospital for medical assessment. Specific treatment is based on antivenom immunotherapy. However, other medical and surgical treatments have limited value.

Resume Le xenon qui est un nouvel agent anesthesique inhale est caracterise par sa rapidite et sa reversibilite d’action ainsi que par une neutralite hemodynamique. Cependant, sa concentration alveolaire elevee en fait plus un adjuvant qu’un agent principal de l’anesthesie et rend incompatible l’administration simultanee de fortes concentrations d’oxygene. Les effets neuroprotecteurs restent a confirmer. L’usage du Xenon represente un surcout important qui invite a reflechir avant la mise a disposition.

This work provides a graphic description of the time course of hemostasis tests results during spontaneous evolution of Echis envenoming and correction of hemostasis disorders with antivenom therapy. The dynamics of fibrinogenemia (g L(-1)), prothrombin time (PT, %), activated partial thromboplastin time (aPTT, patient/normal ratio) and platelet count (Giga L(-1)) were collected from coagulopathic envenomed patients of a 12 years prospective study in Africa. Sixty patients were included. 47 of them (78%) received an antivenom (33 ± 12 ml) and 13 did not. Thirty patients (50%) presented bleeding. Only one patient died. The time for fibrinogen to be more than 1 g L(-1) was 181 ± 116 h (7.5 days) in the spontaneous evolution group versus 40 ± 21 h in the antivenom group (p < 0.0001). The times for reaching a PT above 50% were 140 ± 64 min (5.8 days) versus 25 ± 15 h (p < 0.00001) and for reaching an aPTT less than 1.5 times the normal values, 116 ± 76 h (4.7 days) versus 10 ± 9 h respectively (p < 0.0002). Thrombopenia was not a common feature of Echis envenomation. This study is the first one to provide a chart of the evolution of the hemostatic tests during envenomation caused by Echis bites. The plots enable to estimate that, in Echis envenomation, in the absence of antivenom administration, hemostasis remains severely affected until the 8-10th day of evolution. On the contrary, efficient antivenom against African vipers corrects clotting functions within a few hours.

Summary Snakebites are an infrequent but real risk for travelers. We report a case of envenomation by Bothrops atrox in a traveler to Manaus, Brazil. Rapid administration of specific antivenom prevented the expected systemic disorders. This case gives opportunity to review prevention and first aid measures of snakebites in travelers.

Hypertonic saline improves organ perfusion and animal survival during hemorrhagic shock because it expands plasma volume and increases tissue oxygenation. Because both decreased and increased myocardial performance have been reported with hypertonic saline, the effects of hyperosmolarity and the mechanism accounting for it were investigated in isolated blood-perfused rabbit hearts. Coronary blood flow (CBF), myocardial contractility, relaxation, and oxygen consumption were measured during administration of blood perfusates containing 140-180 mmol sodium concentrations ([Na+]). In two other series of experiments, the role of Na(+)-Ca2+ exchange in the inotropic effect of hyperosmolarity (160 mmol sodium concentration) and hypertonicity (sucrose) were also investigated. Hypertonic [Na+] induced a significant increase in contractility and relaxation, combined with a coronary vasodilation. Myocardial oxygen consumption (MVO2) increased at all hypertonic [Na+] without significant change in coronary venous oxygen tension (PVO2) and content (CVO2). Amiloride (0.3 mmol) inhibited the improved contractility observed with 160 mmol sodium. Similar Na(+)-Ca2+ exchanger blockade did not inhibit the inotropic effect of sucrose. These results confirm the positive inotropic effect of hypertonic [Na+]. The inhibition of this improvement by amiloride suggests that calcium influx through the sarcolemna could be the major mechanism of this effect.

We report a case of scorpion envenomation occurring during combat in Tagab district, province of Kapisa, Afghanistan. A French soldier was stung by a yellow scorpion (suspected Androctonus australis) and sustained systemic envenomation with hemodynamic and neurological manifestations. We discuss the clinical features, prevention, and management of a scorpion sting.

Background: Viperidae bites represent a public health issue in Africa and are responsible for a hemorrhagic syndrome with fatal outcome in the short term. A research on Medline database does not reveal any data definitively demonstrating the efficiency of antivenom in case of delayed administration. The aim of this study, based on a 12-year survey of viperine syndromes in Republic of Djibouti, was to compare the normalization of the hemostasis disorders with an early administration of antivenin versus a delayed administration. Methods: A retrospective study was conducted from October 1994 to May 2006 in the intensive care unit of the French military Hospital, in Djibouti. Seventy-three Viperidae-envenomed patients were included. Antivenin efficiency in correcting hemostatic disorders was analyzed in relation to time to treatment (before or after the 24th hour after the bite). Results: Forty-two patients (58%) presented with bleeding. A consumptive coagulopathy was found in 68 patients (93%). Antivenin was observed to be effective in improving hemostasis, and the time to normalization of biologic parameters was similar, whether the treatment was started before or after the 24th hour after the bite. Conclusion: Antivenin should ideally be administered as early as possible. However, in Africa, time to treatment generally exceeds 24 hours. The results of the present evidence-based study confirm an empirical concept: a delayed time to treatment should in no way counterindicate the use of antivenin immunotherapy, in the case of African Viperidae bites.

In mechanically ventilated patients, disconnection from the ventilator and endotracheal suctioning can induce major arterial oxygen desaturation resulting from apnea, changes in inspired oxygen fraction, and decrease in lung volume. The aim of this study was to test the efficacy of a simple method of delivering oxygen and maintaining lung volume during this process. Our study was conducted in two parts. In the first part, constant-flow insufflation of oxygen (CFI) was used in seven patients ventilated for acute respiratory failure (PaO2/FlO2 = 347 +/- 33 mm Hg) as a means of maintaining arterial oxygenation during apnea and disconnection from the ventilator. CFI was administered via a modified endotracheal tube in which small capillaries allowed delivery of a high-velocity jet flow near the tracheal end of the tube during disconnection from the ventilator. In comparison to apnea alone, CFI prevented a fall in arterial oxygen tension (16 +/- 7 mm Hg during CFI versus 117 +/- 27 during apnea, after 90 s of disconnection in the two situations, p less than 0.001), whereas it did not reduce the development of hypercapnia. The efficacy of CFI resulted both from the injection of oxygen into the trachea and from the maintenance of positive alveolar pressure induced by air entrainment (mean 10.4 +/- 1.1 cm H2O), preventing a fall in lung volume usually occurring after disconnection (+338 +/- 88 ml during CFI versus -344 +/- 64 ml during apnea, p less than 0.01). In the second part of the study CFI was used to prevent arterial oxygen desaturation induced by endotracheal suctioning.(ABSTRACT TRUNCATED AT 250 WORDS)

Scorpion envenoming is less studied in pregnant victims. In this work, the effect of Buthus occitanus tunetanus on parturition in late pregnancy was studied in an animal model. Four groups of six primigravid female rats, each one at the 22nd day of pregnancy, were used. The first two groups had received an intra-peritoneal injection of 500 microg/kg of Buthus occitanus tunetanus crude venom or a physiological saline solution and left until foetal delivery. Then, the time elapsed until the first pup delivery and that separating the first and latest ones were measured. The other two groups served for the uterine electrophysiological activity exploration. Rats were anaesthetized, artificially ventilated and had received an intraperitoneal injection of 500 microg/kg of Buthus occitanus tunetanus crude venom or a physiological saline solution. Our results showed a significant increase of the latency to foetal delivery, labour time, and uterine contractile activity in envenomed rats compared to controls. Such signs are usually seen in dynamic dystocia. It was concluded that Buthus occitanus tunetanus envenoming might induce a dynamic dystocia, when it occurred in late pregnancy.