Scintigraphic diagnosis of tricuspid regurgitation

The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.     

Comparison of firing patterns in oxytocin- and vasopressin-releasing neurones during progressive dehydration

The electrical activity of neurosecretory cells in the supraoptic nucleus of the urethane-anaesthetized lactating rat was examined after periods of water deprivation ranging from 0-24 h. Supraoptic units were identified by antidromic activation following stimulation of the neurohypophysis, and classified as oxytocin or vasopressin cells according to their response during reflex milk ejection. In 65 vasopressin cells, dehydration increased the mean firing rate from 2.1 spikes/sec at 0 h to 6.8 spikes/sec at 24 h and caused a change from a slow irregular to a phasic firing pattern. Thus, after 6 h or more of dehydration, 84-100% of the vasopressin cells fired phasically, compared to 12% under normal conditions. In phasic vasopressin cells , the intraburst firing rates were closely related to the stages of dehydration, rising from a mean of 6.3 spikes/sec at 6 h to 12.0 spikes/sec at 24 h. However, no systematic relationship was observed between the stages of dehydration and the mean burst or silence durations. In 77 identified oxytocin units, dehydration increased the firing rate from 0.9 spikes/sec to 2.8 spikes/sec after 24 h, but only 3 (4%) of the cells showed phasic firing. Instead, the oxytocin units changed from a slow irregular to a fast continuous discharge. In conclusion, both vasopressin and oxytocin neurones are activated during chronic dehydration, but there is a marked difference in the pattern of their response. The phasic firing of the vasopressin cells may be important in increasing the occurrence of short interspike intervals and thus facilitating hormone release.     

Polysialic acid is required for active phases of morphological plasticity of neurosecretory axons and their glia

The morphology of axons and astrocytes in the neurohypophysis changes considerably during physiological stimulation, increasing neurovascular contact and facilitating neurosecretion. We here assessed the contribution of alpha2, 8-linked polysialic acid (PSA), which intervenes in axonal changes during development and covers all neurohypophysial axon and glial surfaces. Using an in vitro model, we first analyzed neurohypophysial ultrastructure under different conditions of plasticity. After 2 h incubation in hyperosmotic medium or with the beta-adrenergic agonist, isoprenaline, neurovascular contact significantly increased, due essentially to an enhanced number of terminals, and gliovascular contact decreased correspondingly. This morphology was maintained during 22 h exposure to isoprenaline and reversed 2 h after agonist washout. Removal of PSA from cell surfaces with endoneurominidase prevented stimulation-related induction and reversal of axon and glial changes but had no effect once remodeling had occurred. PSA, therefore, by promoting dynamic cell interactions, is necessary for plasticity of axons and their associated glia.     

Undiagnosed exercise-induced bronchoconstriction in ski-mountaineers

Because the practise conditions put the ski-mountaineering athletes potentially at risk for exercise-induced bronchoconstriction (EIB), this study was conducted to estimate the prevalence of EIB in this population. Thirty-one highly-trained ski-mountaineers with racing experience participating in the race were evaluated. EIB was determined after a European race at high altitude and frigid conditions. Pre-race investigations included pulmonary function measurements and a questionnaire enquiring about i) training habits, ii) respiratory history during training and/or competition. Pulmonary function was also tested after the race. None of the athletes reported a basal airway obstruction. Two groups were determined after post-race airway response: i) EIB (+) group exhibiting a fall in FEV (1) > or = 10 % (n = 15) and ii) EIB (-) without fall in FEV (1) or fall < 10 % (n = 16). Neither training habits nor baseline lung function were associated with the post-race airway response. Six of the 31 ski-mountaineers had a previous physician-made diagnosis of asthma and/or EIB, nevertheless 23 of our athletes complained about at least one characteristic symptom of asthma during practise. Four of our 15 EIB (+) had a previous physician-made diagnosis of asthma/EIB indicating that 73 % of EIB (+) athletes were undiagnosed for EIB. The proportion of allergic athletes was not significantly different between EIB (+) and EIB (-). This study showed that approximatively half of highly-trained ski-mountaineers with racing experience can develop EIB after a race and that 73 % of them are unaware of the problem.     

L’utilisation de placebos dans le traitement de la douleur: résultats d’une enquête préliminaire en milieu hospitalier

Résumé  Le groupe de travail ?Ethique et douleur? de la Société pour l’étude et le traitement de la douleur (SETD) a effectué une enquête préliminaire relative à l’usage de placebos en milieu hospitalier. L’enquête a été faite par questionnaires dans 19 unités de soins, les réponses de 219 infirmières et 100 médecins ont pu être exploitées. Parmi les médecins 35% utilisent ?parfois? ou ?rarement? des placebos dans le traitement de la douleur, de même que 53% des infirmières. Les placebos sont plus volontiers utilisés dans les douleurs psychogènes, dans les échecs de traitements antalgiques, dans les douleurs chroniques ou devant des plaintes réitérées de malades jugés difficiles. Les commentaires des profesionnnels de santé interrogés montrent que les représentations dominantes de la douleur et des thérapeutiques ne prennent pas en compte les différentes composantes de la plainte douloureuse ni les connaissances actuelles relatives aux mécanismes de l’effet placebo.      

Clinical experience with the mini-extracorporeal circulation system: an evolution or a revolution?

PURPOSE: We studied a cohort of 150 patients operated on with a new cardiopulmonary bypass (CPB) system. This is the mini-extracorporeal circulation (MECC) system. DESCRIPTION: The MECC is a fully heparin coated closed-loop CPB system that includes a centrifugal pump and has a priming volume of 450 mL. Between March 2001 and September 2002, 150 consecutive patients were operated on using the mini-CPB (MECC) method. This includes 105 coronary artery bypass graft and 45 aortic valve replacement patients. The median age was 66.7 +/- 10.7 years with a gender ratio of 3.27 males to 1 female. EVALUATION: The 30-day operative mortality was 1.3%. The hemoglobin concentration was stable and perioperative transfusion was needed in only 6% of all patients. The renal and neuropsychiatric complications were less than 1%. CONCLUSIONS: In our experience, the MECC system is a reliable new concept for CPB with good clinical results.     

For a coordination of the supportive care for people affected by severe illnesses: proposition of organization in the public and private health care centres

The concept of continuous and global care is acknowledged today by all as inherent to modern medicine. A working group gathered to propose models for the coordination of supportive care for all severe illnesses in the various private and public health care centres. The supportive care are defined as: "all care and supports necessary for ill people, at the same time as specific treatments, along all severe illnesses". This definition is inspired by that of "supportive care" given in 1990 by the MASCC (Multinational Association for Supportive Care in Cancer): "The total medical, nursing and psychosocial help which the patients need besides the specific treatment". It integrates as much the field of cure with possible after-effects as that of palliative care, the definition of which is clarified (initial and terminal palliative phases). Such a coordination is justified by the pluridisciplinarity and hyperspecialisation of the professionals, by a poor communication between the teams, by the administrative difficulties encountered by the teams participating in the supportive care. The working group insists on the fact that the supportive care is not a new speciality. He proposes the creation of units. departments or pole of responsibility of supportive care with a "basic coordination" involving the activities of chronic pain, palliative care, psycho-oncology, and social care. This coordination can be extended, according to the "history" and missions of health care centres. Service done with the implementation of a "unique counter" for the patients and the teams is an important point. The structure has to comply with the terms and conditions of contract (Consultation, Unit or Centre of chronic pain, structures of palliative care, of psycho-oncology, of nutrition, of social care). A common technical organization is one of the interests. The structure has to set up strong links with the private practitioners, the networks, the home medical care (HAD) and the nurses services at home (SSIAD), when they exist, to guarantee the continuity of the supportive care under all its aspects and in order to take into account the preferences of the patients. According to Hospital 2007 propositions, the extended, flexible and general purpose Group of Sanitary Cooperation (GCS) meets the necessities inherent to the structures of supportive care within the territories of health because it can be established between one or several health care centres and the private health professionals, thus favouring the cooperation between public and private health care centres. PSPH and general medicine.