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Survival improvement of our haemodialysis patients is partly due to technologic improvement of the dialysis therapy. High permeability membranes and bicarbonate dialysate were the most relevant of past decades. What are the present technologic innovations that will provide clinical benefit? Acetate-free biofiltration, biofeedback systems, better haemodiafiltration techniques and techniques with adsorption could be part of them.

Invasive hospital-acquired aspergillosis (IA) is responsible for lethal outbreaks. In 2002, an interdisciplinary team was created in the teaching hospital of Rouen in order to organize the surveillance of construction sites by the implementation of environmental measures of prevention. The aim of our study was to estimate the efficiency of these measures using an indirect indicator, reflecting the incidence of the cases of invasive nosocomial aspergillosis (AI): the consumption of antifungals. From the nominative prescriptions established, we studied the medical files about 210 patients to track down the number of IA cases in intensive care unit (ICUI) and in pediatric hematology-oncology units between 2002 and 2006. The incidence of the cases was put in parallel with the various periods of level 5-risk works during these five years. The relative risk of appearance of the disease was calculated. In pediatric haematology-oncology unit, 35 cases were diagnosed on 99 medical files which have been studied and in ICU 19 cases were classified on 93 studied files. The follow-up of the incidence in both units stake in parallel with the periods of level 5-risk works does not show increase of the number of cases. The calculated relative risk indicates the same result: the level 5-risk works are not a factor facilitating the appearance of invasive aspergillosis cases. This study shows the importance of the environmental measures of prevention during the periods of works within services for risk. The coordination of the actors within an interdisciplinary cell seems thus essential for the prevention of AIN.

Objective: This work consisted of the assessment of humidification parameters and flow resistance for different heat and moisture exchanger filters (HMEF) used in intensive care unit. Four electrostatic HMEF were assessed: Hygrobac S (Tyco); Humidvent compact S (Teleflex); Hygrovent S/HME (Medisize-Dräger); Clear-Therm+HMEF (Intersurgical)., Material and Methods: Humidification parameters (loss of water weight, average absolute moisture [AAM], absolute variation of moisture) have been evaluated on a bench-test in conformity with the ISO 9360: 2000 standard, for 24h with the following ventilatory settings: tidal volume at 500 ml, respiratory rate at 15 c/min, and inspiration/expiration ratio at 1:1. The flow resistance of HMEFs assessed using the pressure drop method was measured before and after 24h of humidification for three increasing air flows of 30, 60, and 90 l/min., Results: All the HMEFs allowed satisfactory level of humidification exceeding 30 mgH(2)O/l. The less powerful remained the Clear-Therm. Concerning HMEFs flow resistance, results showed a pressure drop slightly more important for the Hygrobac S filter as compared with other filters., Conclusion: This test showed differences between the HMEFs for both humidification and resistance parameters. When compared to the new version of the standards, HMEFs demonstrated their reliability. However, evolution of humidification and flow resistance characteristics over 24h showed a structural degradation of HMEFs, limiting their use over a longer period.

Introduction: For several decades a more peripheral distribution of the broncho-pulmonary pathologies related to tobacco has been observed., Methods: The aim of this study is to examine whether changes in the particle size of cigarette smoke as the result of new manufacturing technologies could play a part in the observed epidemiologic changes through a more distal disposition of smoke particles in the airways. Using a smoking machine and a low pressure electrostatic impactor we measured the particle size of the smoke from six different types of cigarette, representing old and new manufacturing techniques. The effect of a filter was assessed by a size analyser measuring the electrical mobility of the particles., Results: The results show a difference in particle size between the primary smoke inhaled by the smoker, S1 (0.27 +/- 0.03 microm.) and the secondary smoke, S2 inhaled by passive smokers (0.09 +/- 0.01 microm). There is no difference in particle size between the 6 different types of cigarette. Filters dilute the smoke without altering particle size., Conclusion: The recent alterations in the distribution of tobacco related pathologies cannot be explained by changes in particle size in cigarette smoke. The explanation has to sought elsewhere.

This paper evaluates the doses delivered to the patient during several radiological procedures in dentistry: intraoral, panoramic and cephalometric radiography. Different digital techniques now available are compared to the AgBr film and film-screen technique. Absorbed doses at different organs are derived from measurements on dental radiological phantoms. The largest dose reductions are observed for intraoral radiography (31-84%). Significant dose reductions are also found for panoramic and cephalometric radiography (25-70% and 30-60%, respectively). By optimizing the exposure parameters and according to the ALARA principle, the smallest doses should be delivered to the patient that are needed to achieve the required quality of the images. Independently on the technique, the beam size should match as closely as possible the size of the detector. Collimation is particularly important for intraoral radiography. The dose at the thyroid should be kept as low as possible especially for children. For some beam incidences, a thyroid shield is especially efficient. The development of digital radiography and the related advantages should not lead to increasing the number of radiographs. The prescribed and performed types of examinations, and their number, should always be selected based on the clinical situation and on sound clinical judgment and experience in order to solve the raised medical problem.

To prevent cross infection and to improve the management of anaesthetic circuits, the French society of anesthesia and intensive care recommended the use of heat and moisture exchange filter (HMEF). Buying a HMEF needs a procedure with different steps and a product request form must delineate precise needed requirements of the device. In the absence of standardized methods to assess filtration performance, required specifications are established from both manufacturer data and scientific published studies. Proposed purchasing method and criteria help the health care workers at the time of final decision for objective comparison between the different devices on the market.

Prevention of respiratory allergy and thus diminution of its prevalence consists of the application not only of preventative measures on the allergens themselves, but also on atmospheric pollutants such as NO, CO and diesel particles. These modify the allergens and increase synthesis of allergen-specific IgE. Use of air purifiers, on condition that they have HEPA or ULPA filters may contribute to reduction of allergenicity linked to pollutants and are one of the not-negligible means of protection from respiratory allergy and asthma in particular.

Several models among the contemporary disposable bacterial filters, heat and moisture exchangers can be inadvertently inserted into the expiratory port of the Ambu A nonrebreathing valve. Such a misconnection, which does not allow expiration, is made possible because of the respective sizes of the connection ports of the devices. International standards and French regulations specify neither the internal diameter of the expiratory port of the nonrebreathing valves, nor the external diameter of the circuit connecting port of the respiratory filters.

Performances of filter systems for leucocyte removal (Pall BPF4 and Sepacell RZ 200 B) have been studied following the preparation of red blood cell concentrates (RBCCs) obtained either by a soft-spin centrifugation at 2967xg (n = 438) or by a hard-spin centrifugation at 5275xg (n = 187). After deleucocytation, 43, i.e., 9.8% of RBCCs obtained following a soft-spin centrifugation contained a number of residual leucocytes higher than 1 x 10(6) leucocytes/RBCC which represents the legal upper limit in France, whereas RBCCs obtained following a hard-spin centrifugation always contained a number of residual leucocytes lower than this limit. Our results strongly suggest that the quality of deleucocytation depends on an adequate ratio of platelets to leucocytes, which favours the capture of leucocytes by filters. In fact, this ratio was higher in RBCCs obtained following a hard-spin centrifugation. Our results demonstrate that the use of these filters does not allow the removal of leucocytes complying with the legal limit of leucodepletion for all preparations of RBCCs.

Helical CT is the imaging modality that delivers the highest exposure to patients. For each acquisition, the average radiation dose is between 20 and 30 mGy. This dose can potentially be reduced by decreasing the intensity or voltage and by increasing the pitch. Helical data can be reformatted to obtain images with smaller increment or multiplanar reconstructions, hence reducing the need for additional acquisitions. Hardware and software devices designed for dose reduction must be systematically used. Operators of CT units should be aware of the radiation dose delivered with helical CT and must carefully assess the need of each additional acquisition. Obsolete protocols such as angulation of the gantry for lumbar CT, which increases patient exposure, should no longer be used. Rational use of helical CT decreases radiation exposure and is faster, whereas improper use increases radiation exposure without added benefit.

Since 1925, the work of BROADBENT and the invention of the cephalostat (in 5), radiographic cephalometry has enabled us to have a detailed knowledge of craniofacial structures, and to better understand the form of the skull. At the same time it enabled us to understand the maxillo-facial growth and dental maturation. However, they have given rise to many controversies because of magnifying power and distortions. The question posed by magnification is still debated, even if some authors have attempted to solve the problems brought forward by distortion effect which seem to neglect radiographic conical projection. This study aims to appreciate not only the magnifying and its distortion consequences but equally the effect of conical X ray. The authors make use of mathematical equations and attempt to bring forward a correction based on 3D projection.

Leukodepletion is a significant factor of improvement of the quality and safety of blood cell components. By reducing residual leukocytes in the products to a rate below 1 million per unit, the risks of transmitting intralymphocyte viruses, provoking shivers and hypothermia reactions, and inducing anti-HLA alloimmunization are diminished, as well as bacterial contamination risks. The constant improvement of the performance and the use of leukodepletion filters allows this technique to be generalized to all red blood cell and platelet concentrates. Leukocytes retention devices on these filters are numerous and sensitive to the conditions for material use. Implementation of Leukodepletion at production stage must be carried out in a mastered framework of quality assurance.

Several filters specific for respiratory function tests have been on the market for several years. Recommended by the manufacturers to avoid contaminating the equipment and thus improve patient safety, these filters require a considerable financial investment. We studied the passage of diluted blood into artificial saliva in a patient model simulating inspiration tests and rapid forced expiration to assess the retention capacity of three filters used for respiratory function tests: Multi SPIRO MI-90016 (MultiSPIRO), PF 30S (Pall Biomedical) and Spirobac (Dar. S.p.A). The mean percentage of passage was 1.48% through the MI-90016 filter, 57.15% through the PF 30 S filter and 70.45% through the Spirobac filter. These findings provide further elements for choosing filters for respiratory function tests. Indeed, despite the manufacturers' commercial arguments, the technical documents provided do not give necessary information on the filtering capacity of the filters on the market. We have observed that two out of the three filters tested do no meet the standards expected by clinicians.

Objectives: Heat and moisture-exchanging filters (HMEFs) are increasingly used in clinical practice. At the same time, new scientific data are available which clarify the benefits of these devices., Data Sources: We searched in the Medline database for all papers written in English or French, without limiting date of publication, using the following key-words separately or in combination: humidity, temperature, mechanical ventilation, equipment., Study Selection: From the 200 articles provided by Medline, we selected those directly concerning HMEFs. Some older studies and those on HMEFs no longer available were excluded., Data Extraction: Principle data available from the literature were analysed., Data Synthesis: Humidification and warming of the inspired gas mixture is mandatory during mechanical ventilation. There is a direct link between HMEF performance and the characteristics of tracheal secretions. This justified the recommendation for the use of HMEFs with a humidity output above 30 mg of water per litre of gas mixture. In this case, HMEFs are as efficient as conventional heated humidifiers. HMEFs seem to decrease the rate of nosocomial pneumonia in comparison with heated humidifiers. HMEFs induce a slight increase of dead space which should be taken into consideration during weaning from mechanical ventilation. There are demonstrable data in the literature suggesting the possibility of cross viral infection via the anaesthetic machine when an HMEF is not used. There are no data which suggest a specific type of HMEF regarding viral filtration., Conclusion: According to the literature data, using an HMEF is essential in anaesthesia and is highly recommended in intensive care.

The aim of this study is to evaluate the effects of whole blood filtration after a storage time of 20-24 hours at laboratory temperature using the in line filter Leucoflex LST1. The study concerns 49 blood donations in which we studied leukocyte depletion, proteins (IgG, IgA, IgM, haptoglobin, C3, C4), coagulation factors (fibrinogen, factors XII, XI, IX, VIII, V, proteins S and C, plasminogen, tPA, D-Dimers, PDF) at day 1, the parameters of conservation (ATP, 2-3 DPG, extra cellular potassium, haemolysis, pH) of red blood cell concentrates (RCCs) and bacteriological sterility at day 1 and 42. Despite a correct leukocyte depletion (mean depletion of 3.96 log), a 10 fold higher mean level of residual leukocytes/unit than with buffy coat poor RCC filtration (0.514.10(6) vs 0.051.10(6)) is observed. Moreover a lot of concentrates are not in accordance with French regulations (7/42 with more than 1.10(6) leukocytes/unit). The variation of the rates of IgG, IgA, IgM, haptoglobin, C4 and protein C is not significant. For the others there is a slight decrease with a mean level remaining in a physiological range. No sign of activation is noted. The sterility assays remain negative and the RCC conservation is not altered. In conclusion, even if the quality of the leukocyte depletion is not satisfactory in our study and has to be stated more precisely by multicenter studies, the whole blood filtration does not alter the quality of the derived components and allows us obtain RCC in a bigger volume and containing more haemoglobin than with the classical procedure after removing the buffy-coat [10].

We designed a 7-filter digital auditory prosthesis table prototype. For each of these filters frequency band width, amplification and compression were programmable in order to adapt these parameters to the deaf patient's audiometric particularities. We compared the hearing improvement it was possible to obtain with our prototype as a function of the number of filters (3, 4 or 7) and their frequency band width programmability. We tested 21 patients suffering from middle or severe neurosensory hearing loss. This study allows to demonstrate that a 7 programmable-width-filter strategy seems to be the most appropriate.

Many patients with retinopathies and tapetoretinal hereditary degenerations complain about symptoms varying from blinding to intense photophobia or from diminished contrast sensitivity to blurred vision or lowered visual acuity. Protecting optic filters, blocking the blue spectrum of light, may reduce these symptoms. There is no evidence at this time that such filtering glasses would delay or slow down the evolution of the disease.

The study was designed to test the hypothesis that whole cells can be carried as an aerosol in the pneumoperitoneum during laparoscopy. Twelve patients undergoing laparoscopic surgery for benign and metastatic disease were included in the study. Throughout the 12 procedures, the smoke and the gas of the pneumoperitoneum was evacuated through 17 filters. Twelve filters and the tubing were washed. The liquid was centrifuged and stained immunocytochemically to identify the cells. Five other filters were also photographed with an electron microscope. On immunocytochemistry, nine of the twelve samples were identified as mesothelial in origin and the electron micrograph show many other cells stuck to the filter which appeared to be blood cells and mesothelial cells. Malignant cells were not conclusively identified, but ethical considerations prevented any intentional coagulation of malignant tissue. The presence of whole identifiable cells in the pneumoperitoneum could partly explain, port site metastasis after laparoscopic surgery for cancer.

Among photosensitive patients, the use of colored filters sometimes leads to a clear improvement of comfort. After a general review of theory, we start on the way we take care of these patients and the way filters are fitted and made. We only present here a preliminary work. A subsequent study or accurate informations of colored filters will be published later. The aim is to set up a methodic procedure in order to find the best selection of the recommended spectral curve and the best way to follow the progress of the patient as regards the wearing and the effect of the filter. An overview of our cases is presented.

The precise measurement of low numbers of leukocyte below 0.1 WBC/microliter in filtered red cell or platelet suspensions meet both aims: to check the compliance with previously determined requirements and to evaluate the performances of novel filtering material (5 log depletion or more), justified by more and more important clinical use. The reliability of results, obtained with the chosen method, is ensured by applying of validation protocol, including training of technologist, assessment of the analytical range and the detection limit, assessment of precision and accuracy. The flow cytometry (FC) and Nageotte Chamber (NC) method are the both techniques which are currently used in routine Quality Control (QC) and validated by multicenter studies. Recent developments are made for increasing the sensibility of these counting methods, thanks to higher concentration or volume of the sample to be analysed. Among the experimental techniques, requiring more advances before implementing in QC program, quantitative PCR must become essential as reference method for evaluating the efficiency of filtration, in the future.

Several kinds of images, each giving a different information, are now available to radiologists. The MRI images have excellent contrast resolution and enable soft tissues to be differentiated, but they do not distinguish structures with low water content, notably air and bone, whereas these are easily recognized by CT. The aim of this study is to present a simple, entirely radiologist-supervised method to examine the radiological data of any patient, obtained from several kinds of images. MRI is performed using a GEMS Signa, 1.5 Tesla, 4.9 version magnet. Acquisitions are T1- or T2-weighted spin-echo or gradient sequences, with a 256 or 512 matrix, on axial sections, with of without contrast injection. CT is performed using a GEMS Hi Speed scanner. Acquisitions are obtained on a 512 matrix and with a "Soft" or "Bone" filter, without contrast injection. The two series of sections are transmitted, through an Etherne network, to a Sun console where the two corresponding volumes are reconstructed on a GEMS Voxtol by means of a 3-dimensional soft ware for image treatment. At least 3 couples define the rotation and translation required for one of the two volumes to reset it in the guide mark of the other. The soft ware then looks for the best transformation, in terms of least square, between the two 3-dimensional volumes. The calculation demands only a few seconds. One of the two objects is then recalculated in the guide mark of the other. The cursor positioned by the user on any point of the object is linked to a second cursor which will automatically position itself on the corresponding point of the other object. The accuracy obtained (about one millimeter) is specified by the soft ware which indicates how to improve resetting. In addition to its teaching value, this superimposition image can help in the diagnosis and can be used for surgical stimulation because it is possible to mix the images. This mixing gives access to a new type of imaging, since the images spared can be reconstructed in volume, and treated in all planes, as a CT or MRI examination. The term "Anatomical Reconstruction Images" may be suggested for this new type of examination. Beside intermodal comparison, one may also imagine that the soft ware can be used to follow up the patient over time (repeat MRI) or to make comparisons between several objects, although the elastic resetting method is more often appropriate in the second case.

Since their creation, leukocyte depletion filters, used to prepare leukocyte-poor red cell or platelet concentrates, have been continuously evoluting: their volume has been reduced and their composition has been modified, polyester fibers have replaced cotton wool or cellulose acetate. In the same way, their capacity to remove leukocytes has increased. The mechanisms of cell separation are still unclear. Through published studies, different factors seem to be implicated, such as wetable surface of the filter, surface tension or charge density of fibers. It was also observed that removal of lymphocytes from red cell concentrates is rather based on trapping in the fiber network, and that removal of granulocytes, monocytes and platelets is partly due to activation and subsequent adhesion to the fibers. There have been few studies of the mechanism of leukocytes depletion from platelets concentrates.

The leukocyte removal technology of platelet and red blood cell concentrates is now based on the only method: the filtration. In order to perfectly control this technology, it is necessary to know the different parameters that interfere in the quality of the leukocyte removal. These different parameters are studied here. They are classified in two types: the parameters that are related to the concentrate to filtrate: method used for the preparation, age, state (temperature, aggregates), concentration of red blood cells, platelets and leukocytes; the parameters that are related to the leukocyte removal technology and to the different steps of its carrying out: filter type (composition, size, geometry), prefilter, priming of the filter, flow rate during the filtration, rinsing and centrifugation after the filtration, elimination of the air inside the filter and the filtered concentrate, sterile connections, and finally good behavior in front of the difficulties and hitchs that could occur during the filtration procedure.

By means of a questionnaire sent to 1615 dentist practices in 9 Lander of the former West Germany, a survey has been organized of the efficiency of amalgam separators, which had been made compulsory on 1 January 1990. Only 51% seems to be operating without any defaults. The frequency and the nature of the defaults, as well as the cost-price of the repairs have been analysed per type of separator. Separator noise and vibrations are due to the construction. Erroneous sensor signals are contributed to insufficient sealing. Sometimes there is the sensor sensitivity to foaming blood. In order to keep the maintenance related defects to a minimum, the manufacturers have tightened the maintenance instructions up to an unrealistic level. The dentists wonder whether the reliability of these expensive tools (worth an average of 75,000 BF) cannot be improved. More in particular, they demand more reliable electronic sensors, and the rotor as receptacle is only found satisfactory in limited practice circumstances. There is a demand for polyvalent, more reliable amalgam separators.

There is an increased awareness about environmental protection and reduction of toxic waste. This applies also to the dental profession. One of the main concerns in dentistry is the reduction of amalgam slurry, which contains mercury, being drained by dental plants. The largest pieces of amalgam are stopped by the coarse filter. For eliminating the amalgam silt out of the sewage, amalgam separators have been developed. This paper presents an evaluation of seven separators, mounted in a preclinic set-up. The average particle size of the amalgam waste was determined. The flow-velocity of the separators differed very much between the different separators. One apparatus produced an inferior separation capacity compared to the others. Apparently not one was capable to purify the effluent to 0.05 mg/l during peak supplies of amalgam slurry. Other measures such as the reduction of the need for restoring, the use of alternative materials and modified preparation techniques, will further reduce the drain of amalgam silt by dental installations.

Thirteen patients with a tracheostomy who were undergoing artificial ventilation at home were included in a study covering 62 episodes, during a month of treatment, which was undertaken with three different humidification systems: A Puritan Bennet Cascade humidifier (C), a Swedish nose Vygon-(V) (a hydroscopic condenser humidifier) and a Pall filter (P). Five patients abandoned the study because of discomfort with C (1), P (2), or V (2). The discomfort described by three patients was identical with the three systems used during ventilation. The two systems using the artificial heat humidification exchanger were considered more simple to use than the Cascade for the patients. Using the system for three years for a patient who was being ventilated for 12 hours out of 24 showed the increasing cost ranging from the Vygon nose, to the Cascade and finally to the Pall filter. The percentage of time spent on antibiotics was identical with the three systems (11% of the time). A bacteriological study showed that only the Pall filter permitted the respirator tubes to be kept sterile. The most polluted circuit from the bacteriological point of view was that used with the Cascade. In conclusion, when it was compared to the humidifier Cascade the two artificial noses appeared as simple to use and the Pall filter was the safest bacteriologically.

We herein describe a new depth filter media which exhibits selective adsorption properties for lipids of plasma on Zeta Plus Del I (Cuno Europe). Lipids plug chromatographic columns and filter during plasma fractionnation and cause solution instability for the final product. Several parameters which could affect the lipid removal efficiency on Zeta Plus Del I have been investigated: prefiltration, contact time, ionic strength, pH, and temperature. The maximum percentage of total lipids eliminated, in the better operating conditions was 68%. This method has proven to be efficient for the treatment of plasmatic lipids and can be easily incorporated in an industrial process.

We describe a new method for the preparation of standardised therapeutic doses of leukocyte depleted platelets. The first step is to remove the buffy-coat from whole blood units drawn on triple Siamese ACD/SAGM bags (Maco-Pharma) by means of a Compomat (NPBI). The second step is to connect (SCD Haemonetics) six buffy-coats and one plasma to a special kit (Maco-Pharma) including a PALL PL 100 filter; after centrifugation, the supernatant platelet concentrate is extracted, filtered and recovered in a 2 litre TOTM PVC bag. The volume, the number of platelets and leukocytes of these pools are measured. A comparison of these parameters is made with therapeutic doses prepared in the same way without filtration. Besides, pH measurements up to the 6th day of storage and bacteriological checks are carried out. The results show: no platelet loss related to filtration; a synergy between the preparation process out of buffy-coats and the filtration: so each dose contains less than 10(6) leukocytes; a good pH level allowing the storage for five days as it is associated to the bacteriological safety of the functionally closed system. This technique makes it possible to transfuse only leukocyte depleted platelet concentrates. In addition, it offers new prospects for standardisation and quality improvement.

Partial interruption of the inferior vena cava (IVCI) by a percutaneous endovenous filter (Günther filter n = 65, LEM filter n = 36) was undertaken in 100 patients with an average of 72 +/- 11 years for recent deep vein thrombosis. The indications were: contraindications to anticoagulant therapy (36.5%); recurrent pulmonary embolism (12%); threatening venous thrombosis with a previous embolic episode (12%); caval thrombosis (15.7%); prophylactic, with no previous pulmonary embolism (23.8%). The filters were evaluated at short and mid term. There were no technical problems. The mortality rate was 17.5%, one death being probably due to recurrent pulmonary embolism. No other recurrences of pulmonary embolism were observed, indicating an efficacy of 99 per cent. The early patency rate was 96.5%, there being no difference between the two filters used, independent of the initial site of venous thrombosis, of distal migration of the filter and associated medical treatment (anticoagulation). Distal migration was observed in 76% of IVCI by the Günther filter and 48.5% by the LEM filter (p less than 0.001); tilting was observed in 7.4% of Günther and 3% of LEM filters. Five LEM filters were incompletely opened. The IVC was transfixed by 3 Günther filters. One Günther filter had fractured spokes. There were 12 recurrences of lower limb deep vein thrombosis and 16 post-deep vein thrombosis complications were recorded. These percutaneous endovenous filters are similar to the Kimray Greenfield filter with respect to efficacy and permeability although the follow-up was relatively short. The advantages of these percutaneous filters are the facility, innocuity and rapidity of their insertion with, however, a higher incidence of distal migration.

To investigate the capacity of bacterial filters to prevent complications of the central venous nutrition in neonates, 100 percutaneous central catheters were placed in 94 neonates: 50 catheters was used with a bacterial filter and 50 without filter. No significant difference appeared between the 2 groups for the frequency of complications. Complications should be avoided with a rigorous technique in the maintenance.

Kim-Ray filter complications are usually benign, such as angulation or slight migration. We report and compare with the literature one case of vena cava perforation associated with a small bowel lesion. The follow-up with regular abdominal plain X-rays allows detection of filter angulation, the first step before vena cava perforation. Cavography or CT scan depicts this perforation. Complete or partial surgical removal of the filter may be necessary.

Among 37 patients that are admitted for a more than 3 days breathing reanimation, 19 are ventilated with bacterial filter Pall BB 22 15 and 18 with Darex Hygrobac, exchanged every days and connected to the Y piece. In this study, 6 patients are ventilated with a humidifier (pilot population). For these 43 patients, 130 protected swabs were made with the RCS Biotest placed on the expired gaz. The day of the taking off the expiratory tube was rinsed with 100 ml of aseptic water which are strained on the membrane. The two filters give very good and comparable bacteriological results. The filters prevents nosocomial pulmonary infections making a bacterial frontier between the patient and the respirator and reducing aerial contamination from one patient to another.

The aim of this study is to assess wether the use of the bacteriological filter Pall BB 22 15 placed on the Y piece of the anesthesia equipment decreases contamination and furthermore to evaluate the cost of this practice versus changing anesthetic circuits after every patient. Randomized trials are conducted with three "Engström" machines in three cardiac surgery operating rooms. The Y pieces were examined with qualitative and quantitative bacteriological analysis. Use filters is less expensive than changing circuit for each patient for a comparable efficacy.

The exogenous respiratory infections have two transmission channels, the airborne and the handborne ways, and two entrance doors, tracheotomy and intubation. Indeed, most often, contamination of the oropharynx occurs prior to the bacterial pneumonia. These microorganisms are isolated on healthy carries, on linen, furniture, air-conditioning system and so on... Special precautions are recommended as disinfection or sterilization of ventilators equipment changing circuits every 48 hours, using sterile water in humidifiers, and rigorous aseptic technic for tracheal suctions. An experimental study shows that microorganisms present in the humidifier disseminate through the circuit with the airstream. Therefore septic isolation of patients with pneumonia and disinfection of the room after his departure are considered as essential measure of prevention.

The authors analyse the results of the application of 14 Kimray-Greenfield filters; there was neither pulmonary embolism, nor thrombosis of the vena cava inferior nor any other complication. These good results, like those of much more important series which have recorded, prompt us to use the Kimray-Greenfield filter in normal cases. The authors also think that the qualities of the filters mean that they can be used systematically in a preventive capacity, in certain cases where the risk of serious thrombo-embolic illness is especially high and impossible to prevent effectively, owing to specific circumstances.

In 1984, 38 sera from home hemodialysis patients were found with a significant increase of aluminum (Al) from 67.8 +/- 44.3 to 102.0 +/- 45.9 micrograms/l (p less than 0.001) compared to 1983. The only change was an activated charcoal (AC) filter in the water treatment circuit, added downstream of the water softener. Five different home hemodialysis AC filters were tested: Microclean CA Dia Cuno, Traitement Standard des Eaux (TSE)R, Permo, C2R, Gambro. AC was shown to be the main source of Al, its content ranging from 1251 +/- 116 to 7569 +/- 969 mg/kg. Al released in 2000 l of liter rinsing water varied from 1.6 +/- 1.3 to 41.3 +/- 5.5 mg. (mean concentration: 0.8 to 20.6 micrograms/l): Gambro less than or equal to C2R less than TSE less than Permo less than Cuno (p less than 0.01). Al loading of charcoal could occur either before or during the activation process, by contaminated water, other added substances, or during packaging. In conclusion, our study suggests, first, to put AC filters upstream of Al captor to avoid Al intoxication, second, to systematically dose Al and may be other metallic substances in every manufactured AC sold for therapeutic purpose.

20 red cell concentrates (buffy-coat not removed), 5 pools of 5 and 5 pools of 10 standards plateles concentrates, as well as 5 single donor platelet concentrates obtained through Haemonetics V50-1 cytoplasmapheresis procedure, were filtered, within 48 hours after donation, using RC 100 and PL 100 blood filters developed by Pall Company. Using the RC 100 filter on red cell concentrates, the rate of leukocyte removal exceeded 99% of the initial values. The residual leukocyte count per unit was 5.8 +/- 3.4 10(6). Leukocytes in red cell concentrates filtered after a previous one on the same filter numbered 18.6 +/- 8.9 10(6). The rate of platelet removal exceeded 97% of the initial amount. Red cell loss was 6 +/- 9% or 4 +/- 3% of a single or a subsequent unit were filtered respectively. Using the PL 100 filter on platelet concentrates, the rate of leukocyte removal exceeded 88% of the initial values. Residual leukocyte counts were 1.4 +/- 0.4 10(6), 6.2 +/- 3.8 10(6) and 1.4 +/- 0.8 10(6) respectively in 6-unit pools, 10-unit pools and machine prepared platelet concentrates. The average platelet loss was 15%. There was no evidence of alteration in the qualitative parameters of red cells or platelets. The filters were easy to handle and the time needed for the whole filtration process was remarkably short.

Analysis of results of short- and medium-term use of 15 Greenfield's filters (GF) introduced distal to renal veins confirmed the good nephrologic tolerance and efficacy of partial interruption of suprarenal inferior vena cava. The surgical technic necessarily involves use of internal jugular vein (with the exclusion of femoral vein) and it is recommended to insert the GF in the retro-hepatic vena cava at a distance from renal veins. Review of 53 cases reported in the world literature indicates cases suitable for this procedure as being patients with severe thromboembolic accidents unable to be treated by direct surgery, fibrinolysis or by effective anticoagulation. Indications for use of a suprarenal GF include suprarenal extension of a caval thrombus or lack of efficacy of an anterior caval block proximal to renal veins. In these cases, that are rare and should remain so, the suprarenal Greenfield filter is the most satisfactory solution at the present time for ensuring the very poor vital prognosis of this very particular group of patients.

Locomotor activity of lymphocytes from human peripheral blood towards the chemoattractant casein was examined in vitro in modified Boyden chambers with a single micropore filter (according to the Wilkinson's method), and in Keller's chambers with two micropore filters. Using the single filter technique, this paper reports the precise standard parameters necessary for a reproductive assay, that is a filter of 5 micron pore size (Millipore), an incubation of 5 h with 5 mg/2 ml of alpha-casein, and the counting of lymphocytes at the front of migration within the filter. The distinction between the chemotaxis (directional locomotion) and the chemokinesis (random migration) in the presence of the alpha-casein was confirmed with human circulating lymphocytes. When the results obtained with the double filter technique are compared with that of single filter, Keller's method shows no advantage over the single filter technique modified by Wilkinson. The latter appears adequate to study specific and non-specific drug-induced lymphocyte chemotaxis and chemokinesis with normal or pathological cells in man.