Anesthésie locorégionale chez le patient obèse

Objective

To detail specificity of regional anaesthesia techniques in the obese patient.

Data sources

Articles were selected from Medline database using the combination of the following keywords: obesity, peripheral nerve block, spinal anaesthesia, epidural, morbidity, mortality.

Study selection

Most recent original articles or review have mainly been selected. Some case reports that highlighted specific points were added.

Data extraction

Articles were analyzed for advantages and drawbacks, and risks of different techniques in obese patient.

Data synthesis

Techniques avoiding obese patient's mobilization are recommended. The use of skin landmarks may be challenging for both central and peripheral blocks. Ultrasound techniques should improve block performance, even though deep fat layers seem limit sound diffusion. Success rate and incidence of complications are usually increased after regional anaesthesia technique in obese patient. The reduction of intrathecal local anesthetic dose remains controversial in this population.

Conclusion

Regional anaesthesia techniques could represent an alternative to general anaesthesia (less cardiorespiratory complications). However, many specific considerations have to be taken into account.     

Phénotypage métabolique par résonance magnétique nucléaire pour l’évaluation périopératoire et en réanimation

Metabolic phenotyping consists in the identification of subtle and coordinated metabolic variations associated with various pathophysiological stimuli. Different analytical methods, such as nuclear magnetic resonance, allow the simultaneous quantification of a large number of metabolites. Statistical analyses of these spectra thus lead to the discrimination between samples and the identification of a metabolic phenotype corresponding to the effect under study. This approach allows the extraction of candidate biomarkers and the recovery of perturbed metabolic networks, driving to the generation of biochemical hypotheses (pathophysiological mechanisms, diagnostic tests, therapeutic targets…). Metabolic phenotyping could be useful in anaesthesiology and intensive care medicine for the evaluation, monitoring or diagnosis of life-threatening situations, to optimise patient managements. This review introduces the physical and statistical fundamentals of NMR-based metabolic phenotyping, describes the work already achieved by this approach in anaesthesiology and intensive care medicine. Finally, potential areas of interest are discussed for the perioperative and intensive management of patients, from newborns to adults.     

Pronostic des nouveau-nés de mère prééclamptique

Preeclampsia (PE) is associated with 3 main risks for the fetus: perinatal death, intrauterine growth restriction (IUGR), preterm birth. Perinatal mortality is increased in infants with IUGR or asphyxia. Conversely, mortality and morbidity associated with preterm birth are not altered by PE without IUGR or asphyxia. Very preterm infant with IUGR are exposed to high risk of prolonged respiratory insufficiency. Neurological complications of prematurity are not more frequent in infants born to mothers with PE. Nevertheless birth asphyxia, (i.e. placental abruption) is associated with impaired neurological out-come especially in infants with neonatal encephalopathy. Long term outcome of infants born to mothers with PE is strongly correlated to gestational age. IUGR increases the risk of hypertension and metabolic syndrome in adulthood. Acute fatty liver of pregnancy can by caused by a fetal fatty-acid oxidation disorder.     

Comment prédire la prééclampsie ?

Predicting PE would enable a better understanding of the physiological mechanisms responsible for this disease. It would also permit the identification of an at-risk population and consequently ease the set up of clinical trials.     

Répercussions psychocomportementales en périopératoire chez l’enfant

The relevant literature since the 1940s has been collected from the Medline database, using the keywords: child, operation, anxiety, distress, postoperative complications, preparation, premedication, parental presence, prevention. Preoperative anxiety, emergence delirium, and postoperative behavior changes are all manifestations of psychological distress in children undergoing surgery. Preoperative anxiety is most prominent during anaesthesia induction. Emergence delirium is frequent and somewhat independent of pain levels. Postoperative behavior changes most often include separation anxiety, tantrums, fear of strangers, eating problems, nightmares, night terrors and bedwetting. These difficulties tend to resolve themselves with time but can last up to one year in some children. The major risk factors for postoperative behavior problems are young age, prior negative experience with hospitals or medical care, certain kinds of hospitalization, postoperative pain, parental anxiety, and certain personality traits of the child. Currently, tools exist for quantifying anxiety (m-YPAS) and postoperative behavior (PHBQ). It is possible to identify those children who are at risk for postoperative complications during the preanaesthesia consultation by paying close attention to children under six years with higher levels of emotionality and impulsivity and poorer socialization skills with anxious parents. Suggested strategies for reducing child distress include preoperative preparation, premedication, parental presence during anaesthesia induction, and interventions affecting the child's environment, such as hypnosis. There are numerous ways to provide preoperative preparation (information, modeling, role playing, encouraging effective coping) and their effectiveness is proven in the preoperative setting but not during anaesthesia induction or in the operating room. Midazolam has been shown to be an effective preoperative sedative for reducing anxiety. Parental presence during induction has been shown to effectively reduce preoperative anxiety in children in certain contexts (when the parent is calm and the child is anxious). It is worthwhile if it is integrated into a family-centered anxiety management program and remains one of several options offered to families. Overall, taking into account the child's psychological needs should be considered an essential part of paediatric anaesthesia. Tools and techniques are available for assessing and managing the perioperative distress experienced by children.     

Une complication de l’anesthésie péridurale : la rupture d’un cathéter

We report the breaking of an epidural catheter, which occurred during the procedure of insertion. If such a breaking is a rare event, it is due in this case to an aberrant trajectory of the catheter. By studying the literature, we also analyzed the mechanisms which can lead to the breaking of an epidural catheter. We recommend a precise radiological examination to localise the trapped catheter among the nervous structures.     

L’oxymétrie cérébrale transcutanée en anesthésie pédiatrique

Cerebral oximetry allows continuous real-time and non-invasive monitoring of cerebral oxygen saturation (cSO₂), by measuring oxyhaemoglobin and deoxyhaemoglobin near infrared light absorption, similarly to pulse oximetry. cSO₂ measurement predominantly reflects brain venous compartment, and is correlated with jugular venous saturation. As jugular venous saturation, cSO₂ must therefore be interpreted as a measure of balance between transport and consumption of O₂ in the brain. Cerebral oximetry should be used as a trend monitoring, because its accuracy is insufficient to be considered as reliable measure of absolute value of ScO₂. In adult, correction of intraoperative cerebral desaturation reduces hospital stay, heavy morbidity and mortality, and serious postoperative neurocognitive impairment after cardiac and major abdominal surgery. In children, the occurrence of intra- and postoperative cerebral desaturations during congenital heart surgery is associated with increased neurological morbi-mortality. Cerebral oximetry could be a useful monitoring during anaesthesia of (ex) preterm neonates, due to the risk of impaired cerebral blood flow autoregulation in these patients.     

Amélioration transitoire d’un syndrome Parkinsonien après anesthésie générale

We describe the case of a patient with an untreated Parkinson's disease who underwent surgery for a temporal meningioma. Extrapyramidal syndrome, initially attributed to the meningioma, had improved over the 48 hours following the procedure and then reappeared. This observation raises the question about the impact of drugs used during perioperative days in patients with Parkinson's disease not treated with levodopa.     

Hémorragie intracérébrale spontanée secondaire à un déficit congénital en facteur XIII

Deficiency of coagulation factor XIII is a rare anomaly. The risk of intracranial haemorrhage is particularly high at any age, either spontaneously or during minor trauma. We report a case of spontaneous intracerebral haemorrhage in a child carrying a known deficiency of factor XIII.