Model-based analysis of potassium removal during hemodialysis
| Autor: | Antonio Santoro, Andrea Ciandrini, Francesco Fontanazzi, Stefano Severi, Michele Buemi, Pietro Bajardi, Carlo Mura, Fabio Grandi, Fabio Badiali, Silvio Cavalcanti |
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| Přispěvatelé: | Ciandrini A, Severi S, Cavalcanti S, Fontanazzi F, Grandi F, Buemi M, Mura C, Bajardi P, Badiali F, Santoro A. |
| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
Adult
Male Sodium-Potassium-Exchanging ATPase Potassium Biomedical Engineering Analytical chemistry Medicine (miscellaneous) chemistry.chemical_element Bioengineering Models Biological Biomaterials Hemodialysis Solutions Diffusion Kidney Failure Models blood Renal Dialysis Extracellular blood/therapy Homeostasis Humans Computer Simulation chemistry/metabolism/therapeutic use Na+/K+-ATPase Chronic Aged Chemistry Reproducibility of Results General Medicine Middle Aged Biological Adult Aged Computer Simulation Diffusion Female Hemodialysis Solutions chemistry/metabolism/therapeutic use Homeostasis Humans Italy Kidney Failure blood/therapy Kinetics Male Middle Aged Models Biological Nonlinear Dynamics Potassium blood Renal Dialysis Reproducibility of Results Sodium-Potassium-Exchanging ATPase metabolism const Kinetics Biochemistry Italy Nonlinear Dynamics Kidney Failure Chronic Female Intracellular |
| Popis: | Potassium ion (K(+)) kinetics in intra- and extracellular compartments during dialysis was studied by means of a double-pool computer model, which included potassium-dependent active transport (Na-K-ATPase pump) in 38 patients undergoing chronic hemodialysis. Each patient was treated for 2 weeks with a constant K(+) dialysate concentration (K(+)(CONST) therapy) and afterward for 2 weeks with a time-varying (profiled) K(+) dialysate concentration (K(+)(PROF) therapy). The two therapies induced different levels of K(+) plasma concentration (K(+)(CONST): 3.71 +/- 0.88 mmol/L vs. K(+)(PROF): 3.97 +/- 0.64 mmol/L, time-averaged values, P < 0.01). The computer model was tuned to accurately fit plasmatic K(+) measured in the course and 1 h after K(+)(CONST) and K(+)(PROF) therapies and was then used to simulate the kinetics of intra- and extracellular K(+). Model-based analysis showed that almost all the K(+) removal in the first 90 min of dialysis was derived from the extracellular compartment. The different K(+) time course in the dialysate and the consequently different Na-K pump activity resulted in a different sharing of removed potassium mass at the end of dialysis: 56% +/- 17% from the extracellular compartment in K(+)(PROF) versus 41% +/- 14% in K(+)(CONST). At the end of both therapies, the K(+) distribution was largely unbalanced, and, in the next 3 h, K(+) continued to flow in the extracellular space (about 24 mmol). After rebalancing, about 80% of the K(+) mass that was removed derived from the intracellular compartment. In conclusion, the Na-K pump plays a major role in K(+) apportionment between extracellular and intracellular compartments, and potassium dialysate concentration strongly influences pump activity. |
| Databáze: | OpenAIRE |
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