Thèse--Doct.-ing.--Nancy 1, 1971. / Bibliogr. f. 51-53.

No description available.

A major complication associated with cardiopulmonary bypass (CPB) is acute kidney injury (AKI), with around 30% of patients experiencing some sort of renal insult (31). Kidney performance is strongly linked to cardiac performance, so perfusionists can play a major role in implementing strategies to reduce the incidence of AKI. The use of Near Infrared Spectroscopy (NIRS) has been validated for the use of cerebral oximetry for both pediatric and adult patients, unlike somatic monitoring where only pediatric randomized control trials have proven to be successful. Since the distance from sensor to organ for adults is greater than 1.4 centimeters, there are not any studies to correlate perfusion parameters to adult renal oximetry. The primary goal of this pilot study was to correlate renal oximetry values to pre-established perfusion outcome markers that are routinely measured during CPB. In this way, renal NIRS may be used as a real time trending device to help prevent AKI. The INVOS™ system was used for both cerebral and renal NIRS monitoring. Renal oximetry pads were placed between the 11th-12th intercostal spaces and the most accurate baseline rSO2 (regional oxygen saturation) level was obtained before sedating the patients. Baseline variables obtained were: age, weight, height, body surface area, history of diabetes, ejection fraction, creatinine, hemoglobin, hematocrit, cerebral oximetry, renal oximetry, and lactate values. Operative variables obtained were: hemoglobin, mean arterial pressure, pump flow, cardiac index, cerebral oximetry, renal oximetry, lactate, temperature, venous oxygen saturation, and oxygen delivery. A multivariable statistical analysis model was used to correlate the data. The results showed the strongest statistical correlations of renal oximetry with hemoglobin (p<0.01, p=0.01), cardiac index (p<0.0001, p<0.01), and oxygen delivery (p<0.0001, p<0.0001). The higher these variables were, the higher the renal oximetry values and vice versa. The changes in oxygen delivery were correlated to the changes in renal oximetry values. Specifically as the DO2 increases 1.15 mL/min1/m2 (p<0.01), the percent change in the left renal oximetry increases 1%. As for the right renal, when the DO2 increases 0.94 mL/min1/m2 (p<0.01), the percent change in the right oximetry increases 1%. A renal oximetry value with a decrease of more than 20% from pre-operative baseline is associated with a significantly lower DO2 than renal oximetry values without a decrease more than 20% from pre-operative (p=0.01). The DO2 difference was calculated at 21.97 ml/min1/m2. There is a direct correlation between oxygen delivery values and renal oximetry saturation values. In conclusion, this pilot observational study has shown the INVOS™ system to be a valuable real-time trending device for renal oximetry saturation values with perfusion parameters to help prevent or reduce acute kidney injuries for cardiopulmonary bypass patients.

Thesis (doctoral)--München, 1982.

No description available.

No description available.

No description available.

No description available.

No description available.

L’optimisation de l’administration des médicaments par perfusion intraveineuse doit prendre en compte l’exactitude du débit et doit assurer la délivrance de la totalité de la dose prescrite. Or, lors de l’administration des perfusions par gravité simple, l’irrégularité du débit résulte principalement en un allongement non contrôlé du temps de perfusion. Par ailleurs, l’absence de rinçage des lignes de perfusion après administration conduit à ne pas administrer une partie de la dose prescrite au patient. Dans le domaine de l’oncologie, les recommandations récentes renforcent la contrainte de protection des personnels pharmaceutique et soignant lors de la manipulation des médicaments anticancéreux, en préconisant de rincer les lignes de perfusion après administration, compte tenu de la dangerosité des cytotoxiques. Ceci a conduit au développement d’un dispositif médical spécifique dont l’objectif est de répondre le plus simplement possible à ces recommandations. Toutefois, l’impact du débit de perfusion et l’influence de cette recommandation sur les paramètres pharmacocinétiques des médicaments anticancéreux injectables n’ont jamais été clairement établis. L’objectif de ce travail est d’étudier l’influence potentielle des deux critères de perfusion (débit et rinçage à la fin de l’administration) sur les paramètres pharmacocinétiques des médicaments administrés. Il repose sur la proposition de modèles mathématiques d’écoulement des perfusions par gravité ainsi que sur une application en pratique clinique. Ainsi, le degré d’implication des facteurs de variation retenus dans ces modèles mathématiques sur la mise à disposition des principes actifs pourra être déterminé. Ce travail est organisé en trois parties. La première partie a pour objectif de replacer le dispositif développé dans le contexte commercial actuel ainsi que dans le contexte des recommandations. Dans cette même partie, une étude in vitro de l’impact de ce dispositif sur les critères de perfusion évoqués a été réalisée. Celle-ci démontre que le dispositif ne modifie pas le débit des perfusions par gravité et permet d’administrer la totalité de la dose prescrite. La deuxième partie a pour objectif d’exposer les modèles mathématiques de l’impact du système de perfusion sur le débit des perfusions par gravité, selon le récipient dans lequel est conditionnée la solution à perfuser : un flacon rigide, une poche rigide ou une poche souple. Dans ces modèles, deux facteurs principaux de variation du débit ont été considérés : la perte de charge dans le récipient au cours de l’écoulement ainsi que le fluage du perfuseur. Trois études sont présentées dans la troisième partie. La première a pour objectif d’étudier l’écoulement des perfusions par gravité à partir d’une solution conditionnée en poche souple, afin de vérifier expérimentalement le modèle mathématique correspondant. Les résultats confirment le fait que, comme supposé dans le modèle théorique, la perte de charge au cours de la perfusion et le fluage du perfuseur sont les principaux facteurs de variation du débit des perfusions par gravité. Dans un second temps, l’impact du mode de perfusion sur les paramètres pharmacocinétiques de deux molécules, l’amikacine et la gemcitabine, a été étudié au travers de deux études cliniques. L’étude sur l’amikacine montre qu’un allongement significatif de la durée des perfusions par gravité peut conduire à modifier significativement la concentration plasmatique maximale, critère reconnu comme paramètre d’efficacité de cet agent thérapeutique. / Improving the drug administration process by intravenous infusion means paying attention to flow-rate accuracy and guaranteeing that the entire prescribed dose is delivered. Now, when a drug is administered by gravity-fed infusion, flow-rate irregularity is principally due to an uncontrolled increase in infusion time. Moreover, the absence of a rinsing step after administration results in losing a fraction of the prescribed dose. In the field of oncology, the latest recommendations reinforce the constraint to rinse the infusion line after administration, by considering drug hazard for the nursing staff. This has led to the developing of a dedicated medical device whose objective is simply to respect these recommendations. However, the impact of infusion flow-rate and the benefits of line rinsing on the pharmacokinetic parameters of infused cancer drugs have never really been explored. This work aims to study the potential influence of these two infusion criteria on the pharmacokinetic parameters of drugs administered by infusion. It is based on the result of a mathematical model of gravity-fed infusion flow and on an application in clinical practice to determine the degree of involvement of the identified parameters on drug disposition. This work is divided into three parts. The objective of the first section is to place the medical device we have developed in an economic context and within the framework of the latest recommendations. Its impact on the two criteria cited above was studied through an in vitro experiment. This study demonstrates that the device itself does not modify gravity-fed infusion flow-rate but ensures that the totality of the prescribed dose is administered. The second part aims at presenting the different mathematical models concerning the impact of the infusion system on gravity-fed infusion flow-rate, according to the recipient in which the solution to be infused is conditioned: rigid vial, rigid bag, and flexible bag. In these models, two main variation factors were considered: pressure drop inside the recipient during infusion and infusion device creep. Three studies are described in the third section. In the first, the flow of gravity-fed infusion for a solution in a flexible bag was assessed to verify the corresponding mathematical model through experimentation. The results corroborate those of the theoretical model, i.e. the main factors causing flow-rate variation are pressure drop and creep. Secondly, the impact of the infusion technique on the pharmacokinetic parameters of two therapeutic molecules (amikacin and gemcitabine) was explored through two clinical studies. The amikacin study demonstrates that in the case of a considerable increase in infusion time during gravity-fed infusion, a significant reduction in maximal concentration may result. For a concentration-dependent antibiotic, treatment efficacy is known to depend on this parameter, which raises the question whether the amikacin infusion flow-rate with infusion pumps should not be systematically controlled to improve treatment efficacy. In the gemcitabine study, no significant difference was observed in the pharmacokinetic parameters for the three infusion techniques: infusion pump, gravity-fed infusion followed or not by a rinsing step. These contrasting results for amikacin and gemcitabine may be explained by factors such as different administration conditions and pharmacokinetic behaviour. Nonetheless, the results of the gemcitabine study confirm that the rinsing step, which is strongly recommended, does not alter the quality of care for patients receiving this drug. In conclusion, this work introduces an improved approach to the administration of drugs by infusion. To optimize this, medical devices for infusion should be assessed on suitable drug disposition criteria, and an evaluation made of their potential to modify the pharmacokinetic parameters of therapeutic drugs.