Scanning laser ophthalmoscope imaging of fluorescein-labelled blood cells

Purpose: To demonstrate the feasibility of a technique for the visualization by scanning laser ophthalmoscope (SLO) of fluores cein-labelled autologous leukocytes and platelets in retinal vessels. Method: Individual blood samples from rats and rabbits were centrifuged to isolate platelets and leukocytes, then passively labelled with fluorescein and reinjected into the same animal. An SLO was used to visualize and record cell displacement in the retinal circulation. Labelled platelets were analysed by flow cytometry. Results: By SLO, platelets appeared as a heterogeneous particle flow, and individual leukocytes appearing as brighter spots could easily be traced. Flow cytometry showed that after labelling platelets were well individualized and their size was slightly increased. Conclusion: Circulating blood cells can be visualized in retinal vessels by a simple method consisting of passive labelling of autologous platelets and leukocytes by fluorescein. No platelet toxicity was detected. This method could be applied to the study of blood cell movement in human retinal vascular diseases.Proprietary interest category: N     

Efficacy of a support group programme for care-givers of demented patients in the community: a randomized controlled trial

Dementia induces morbidity not only in the patients but also in the families taking care of them. Many studies described the impact of care-giving on physical and psychological health. Support groups were designed to alleviate the burden of care-givers. The objective of this study was to measure the efficacy of a support group programme for care-givers of demented patients in the community. Forty-one primary care-givers were randomly assigned to a study (n=23) or a control group (n=18). Subjects of the study group attended a structured programme of eight 2-h sessions. These weekly sessions consisted of information on the disease, role-playing on management of behavior problems, discussion on emotional impact of care-giving, and learning of stress management techniques. Subjects of the control group were referred to informal monthly meetings of the Alzheimer's Society. Subjects of both groups were evaluated at the entry (T1), after 8 weeks (T2) and after 8 months (T3). The outcome variables were the Burden Interview, the Revised Memory and Behavior Problems Checklist, the Brief Symptoms Inventory, the Alzheimer's Disease Knowledge Test and a questionnaire on health care utilization. Compared with the control group, subjects of the study group yielded only a significant increase in knowledge about the disease (p<0.0001) but no significant difference on the other outcome variables. It is concluded that this type of support group programme seems to have only a minimal impact on morbidity and on the burden of care-givers. These results are similar with two other studies examining the same issue.     

Effets de l’halothane sur la ventilation et les gaz du sang artériel chez le rat avec ou sans paralysie diaphragmatique

Certains patients atteints de paralysie diaphragmatique ou de dysfonctionnement diaphragmatique maintiennent leur ventilation par la mise en jeu d’autres muscles que le diaphragme. L’anesthésie, modifiant le fonctionnement de ces muscles, représente un risque potentiel chez ces patients. Afin d’évaluer ce risque, nous avons étudié les effets de l’halothane sur la ventilation et sur les gaz du sang artériel sur un modèle de paralysie diaphragmatique bilatérale, le rat phrénicectomisé. L’étude a été réalisée sur 43 rats. L’efficacité de la phrénicectomie a été contrôlée par l’observation directe, après laparotomie. La laparotomie n’entraine pas de modification des gaz du sang. Chez 23 rats, une laparotomie a été effectuée et une artère carotide a été cathétérisée. Chez 11 rats témoins, les nerfs phréniques ont été abordés, sans être sectionnés. Chez 12 rats, les phréniques ont été sectionnés. La ventilation a été mesurée par une technique pléthysmographique, chez les rats éveillés, avant et après l’opération, puis chez les mêmes rats anesthésiés avec 1,1%, d’halothane inspiré. Les gaz du sang ont été mesurés après l’opération chez les rats éveillés, puis anesthésiés. Chez les 23 rats opérés on observe, après l’opération, une diminution du poids et de la température centrale, plus importante chez les phrénicectomisés que chez les témoins. Chez les 11 rats témoins, après l’opération, la ventilation augmente, sans modification des gaz du sang. Chez ces rats, l’halothane provoque une diminution de la ventilation minute et de la PaO₂ et une augmentation de la PaCO₂. La phrénicectomie entraine chez les 12 rats, éveillés, une augmentation de la ventilation minute, une hypoxémie et une hypercapnie. Chez ces rats, l’halothane entraine le décès dans trois cas, une diminution de la ventilation minute et une hypercapnie et une hypoxémie importantes chez les neuf autres rats. Les modifications des gaz du sang sont plus importantes que chez les témoins anesthésiés. Chez le rat intact, l’halothane provoque des modifications des gaz du sang comparables à celles observées chez d’autres espèces et chez l’homme. La présente étude confirme les effets de l’halothane sur les muscles respiratoires autres que le diaphragme. Elle met en évidence le risque respiratoire majeur que l’anesthésie peut fair courir aux patients dont la ventilation est maintenue par d’autres muscles que le diaphragme.     

Retransplantation of the liver after side-to-side caval anastomosis

Caval reconstruction in orthotopic liver transplantation is generally performed by two end-to-end anastomoses, using a portal and caval-axillary bypass to sustain hemodynamic stability. In the piggyback modification, the donor's suprahepatic inferior vena cava (IVC) is anastomosed end-to-side to the recipient's preserved IVC. We have used a recently described variant of the piggyback in 18 patients in whom both IVCs are anastomosed side-to-side. We report two patients who needed three retransplants after this reconstruction and conclude that regrafting can be performed in a quick and safe manner.     

Interleukin-1Β, interleukin-6, and growth hormone levels in human follicular fluid

Purpose To investigate possible relationships of interleukin-1 (IL-1, interleukin-6 (IL-6), and growth hormone (GH) with biochemical variables in human follicular fluid (FF) and selected in vitro fertilization (IVF) parameters.Methods A total of 67 FF samples (n=67 patients undergoing oocyte retrieval for IVF) was evaluated. IL-1, IL-6, GH, hLH, FSH, PRL, hCG, testosterone, total protein, fibrinogen, sialic acid, ₁-antitrypsin, plasminogen levels, and spectrophotometric absorbance at 458 nm were analyzed for selected FF. IL-6 and GH levels of serum and FF samples were also compared (n=23).Results Immunoreactive levels of IL-1, IL-6, and GH were detected in all FF samples. A positive correlation existed for IL-6 (r=0.5069, P=0.0161 when serum-to-FF levels were compared (concentration ratio, 11.857). Smaller-volume follicles (<4 ml) were associated with high IL-1 levels (P=0.0229, and an additional tendency of IL-1 to decrease with increasing embryo cleavage and scoring was observed. With the exception of a weak positive correlation between follicular IL-1 and testosterone levels (r=0.3128, P=0.025, no other relationship with biochemical variables or IVF parameters (etiology, e.g., endometriosis) could be implicated.Conclusions Substantially higher IL-6 levels occurred in FF compared to serum, thus supporting intrafollicular production. Interleukin- 1,IL-6, and GH levels in FF are, however, unsuitable markers for in vitro fertilization outcome.     

Hemodynamic effects of medical antishock trousers during mechanical ventilation

Purpose

To compare the hemodynamic effects of medical antishock trousers (MAST) inflation in mechanically ventilated patients with normal and poor left ventricular function.

Methods

Twelve patients requiring respiratory support were divided into two groups according to baseline transesophageal echocardiography (TEE) measurements: normal left ventricular dimensions and fractional area of contraction (FAC=61 ± 5%) (n=7) and dilated cardiomyopathy with reduced FAC (21 ± 1%) (n=5). All patients were studied when two successive levels of load (mild load by inflation of the leg compartment of MAST at 50 cmH₂O and high load by adding the abdominal compartment of MAST inflated at 30 cmH₂O) were applied. Global left ventricular systolic function was assessed on the TEE transgastric short-axis view. End-systolic wall stress (ESWS) was used as an indicator of left ventricular afterload.

Results

Total respiratory, lung and chest wall compliances were reduced by 48%, 51% and 27% respectively at the high load level (P < 0.05). Whereas no hemodynamic changes occurred at mild load, the high load level produced an increase in left ventricular afterload as evidenced by concomitant increases in diastolic arterial blood pressure (66 ± 6 to 79 ± 6 mmHg,P < 0.05) and ESWS (69 ± 12 to 74 ± 12 Kdyn·cm^?2·m^?2,P < 0.05). In patients with dilated cardiomyopathy, this increase in afterload impaired the left ventricular systolic function and end-systolic area increased (19.0 ± 2.5 to 21.4 ± 2.9 cm²·m^?2,P < 0.05) while FAC decreased (22 ± 2 to 16 ± 2%,P < 0.05). Left ventricular end-diastolic area remained unchanged during the study in both groups.

Conclusion

MAST inflation impairs respiratory mechanics and global left ventricular systolic function in cardiac patients without changes in left ventricular preload.