Renal Function in the Dog in Acute Disturbances of the Acid-Base Balance

An neun Hunden wurde die Elektrolytausscheidung im Harn nach induzierten akuten Säure-Ba-sen-Störungen untersucht. Bei respiratorischer Alkalose stiegen der Harnfluß und die Bikarbonatausscheidung sehr rasch an. Die Ausscheidung von Kalium und oft auch von Natrium war erhöht. Die glomeruläre Filtrationsrate gemessen an der Kreatin-Clearance blieb unbeeinflußt. Der Harnfluß sank sehr rasch, wenn der Pco² anstieg- Bei metabolischer Alkalose verursachte eine hohe Bikarbonatausscheidung eine osmotische Diurese. Die glomeruläre Filtrationsrate blieb unbeinflußt. Die Ausscheidung von Elektrolyten (Na, K, CI, Ca, Mg) stieg an. Bei metabolischer Azidose sank die glomeruläre Filtrationsrate, was zu einem niedrigen Harnfluß fährte. Die Säureausscheidung stieg anfänglich an, aber mit steigender Azidose nahm der Harnfluß ab, was verminderte Säureausscheidung zur Folge hatte. In einem gewissen Stadium der Azidose konnte der Ionengradient zwischen Blut und Harn nicht mehr aufrecht erhalten werden. Dies verursachte eine Zunahme der Azidose, die zu weiterer Verminderung des renalen Blutstromes und der G.F.R. fährte. Wenn der renale Blutstrom abnahm, war die Elektrolytausscheidung reduziert, obwohl die Konzentration der Elektrolyte im Harn hoch war. Vorlaufige Untersuchungen über den Einfluß von Mannitolinfusionen ergaben, daß der Harnfluß trotz der metabolischen Azidose anstieg. Die Ausscheidung von Elektrolyten war nach den Mannitolinjektionen reduziert. Mögliche Wirkungsmechanismen des Mannitols werden diskutiert.     

Considerations in Selection and Management of Patients Undergoing Valve Replacement with Glutaraldehyde-Fixed Porcine Bioprostheses

From November, 1973, through June, 1978, 428 operations in 425 patients were performed for replacement of aortic, mitral, or aortic plus mitral valves, utilizing 277 Hancock and 180 Carpentier-Edwards bioprostheses. Actuarially determined survival at 36 months was similar for all three groups and compared favorably with our experience with the Björk-Shiley prosthesis. Certain patient-related variables influencing late survival were identified by multivariate analysis and included previous operation for congenital heart disease, coronary artery bypass grafting in nonaortic valve replacement, race (black), age at operation, and New York Heart Association Functional Class. A small but definite incidence of thromboembolism occurred in all three groups, again similar to our experience with the Björk-Shiley prosthesis. Multivariate analysis identified four factors influencing risk of thromboembolism: previous cardiac operation, age, double-valve replacement, and rhythm at discharge. Valve degeneration occurred, primarily in children and young adults. Over the medium term, the porcine bioprosthesis compared favorably with mechanical prostheses in terms of survival, function, and thromboembolism. Certain patient-related variables affecting survival may be modified by earlier surgical intervention.     

Selection of Modality of Renal Replacement Therapy

The proliferation of new technologies has led to the availability of a broad range of options for the management of renal replacement therapy (RRT) in patients with acute kidney injury. We provide a review of the published literature comparing the continuous RRTs (CRRT) with other modalities of renal support, including intermittent hemodialysis and the more recently described "hybrid" therapies such as sustained, low efficiency dialysis as well as compare arteriovenous and venovenous and convective and diffusive modalities of CRRT. While there is clear evidence that venovenous therapies are superior to arteriovenous therapies, current evidence does not support superiority of convective when compared with diffusive therapies or greater survival or recovery of kidney function with any individual modality of RRT. Selection of modality of RRT should therefore rely on the resources and expertise available.     

Errors in the Selection of Dialysate Concentrates Cause Severe Metabolic Acidosis During Bicarbonate Hemodialysis

Abstract: Severe metabolic acidosis occurred during bicarbonate hemodialysis as the result of an error made in the selection of the dialysate concentrate. We questioned whether or not it was possible for the dialysis equipment to regulate the proportions in the dialysate fluid using an incorrect dialysate concentrate and still obtain the proper conductivity. We simulated this situation in vitro and found that during bicarbonate dialysis an inappropriately acidic dialysate fluid could replace the normal dialysate with an adequate range of conductivity still being maintained and therefore no triggering of alarms. The investigation showed that the dialysis machines were not adequately adjusted for sensitivity to the concentrates being employed during dialysis. We concluded that dialysis equipment should be fitted with on-line pH meters with alarm systems.     

人工关节置换术后感染的治疗体会

目的探讨人工关节置换术后感染的原因、再手术的时机和方法的选择。方法自1992年1月至2008年6月我院共收治10例人工关节置换术后感染患者,7例髋关节置换,3例膝关节置换;其中男性5例,女性5例;年龄43～74岁,平均64.25岁。术后感染发生在3个月内者4例,1年内者3例,2年以上者3例。3例行清创、置管持续冲洗,静点或口服抗生素,其中1例行假体取出,关节旷置。1例因术中冰冻切片白细胞计数少于5个/高倍视野而行一期关节翻修。6例二期关节翻修。结果随访0.5～18年,平均随访9.25年。8例患者无感染复发迹象,感染治愈率80%。这其中6例疼痛消失,能独立行走,关节功能满意;1例术后形成无痛性假关节,可行走;1例因患者拒绝行翻修术,故行抗生素骨水泥临时假体取出截肢术。2例患者感染反复发作,口服及静点抗生素暂时控制感染。结论预防感染重于治疗。一旦关节置换术后感染发生,应尽早将假体取出。术中病理切片检查对诊断感染和决定手术方式有指导意义。二期行翻修术感染治愈率更高,假体置入更安全。     

Nursing Management of Continuous Renal Replacement Therapy

With CRRT becoming the preferred treatment for acute renal failure, more and more centers will be using this form of therapy. The preparation and on-going education of the nursing staff and their man-agement of the therapy determine the success of CRRT. It is imperative that nurses have clinical andtechnical expertise in the therapy in order for the patient to have positive outcomes on CRRT.