摘要:
Methods for detecting the condition of a catheter providing access to a patient's blood vessel are disclosed in which the blood is supplied to an extracorporeal blood flow circuit. The method includes generating a pressure wave on one side of one of the access points for supplying blood to the extracorporeal blood flow circuit or returning the blood to the patient, then sensing the pressure wave on the other side of the access points. Apparatus for detecting the condition of the catheter are also provided.
摘要:
A container for a sterile medical solution comprises an upper surface, a lower surface, and a rigid top border having a central portion and peripheral portions. At least one separation line joints the upper and lower surfaces of the container to form first and second compartments. The top border of the container includes lines of weakness in the central portion thereof to form a hinged connection between the peripheral portions of the top border so that solutions in the first and second compartments are more quickly mixed when openable connectors between the compartments are broken.
摘要:
Methods for measuring the flow differential through a dialysis machine are disclosed in which the dialysis machine includes a heat exchanger having a primary side and a secondary side for exchanging heat therebetween. The method includes measuring the temperature differences across the primary and secondary sides of the heat exchanger and calculating the flow differential based upon these measured temperature differences. Apparatus for measuring such a flow differential is also disclosed, as are methods for calibrating that apparatus.
摘要:
Apparatus for monitoring flow of a dialysis fluid through a dialyzer is disclosed including a computer for calculating the flow rate of the dialysis fluid into and out of the dialyzer based on the formula P-P.sub.O =k*Q.sup.n in which P is the pressure in the dialysis fluid between a throttle and a pump either upstream or downstream of the dialyzer, P.sub.O is the pressure in the dialysis fluid on the opposite side of the throttles from the pump, k is a characteristic coefficient for the throttle, Q is the flow of the dialysis fluid through the throttle, and N is a characteristic exponent for the throttle, and the apparatus includes microprocessor for calculating the values of k and P.sub.O prior to use and for calculating the value of P.sub.O during use of the dialyzer. Methods for carrying out such monitoring are also disclosed.
摘要:
Methods for measuring the effect of dialysis treatments are disclosed in which a fraction of the used dialysis fluid is extracted downstream of the dialyzer for analysis of at least one substance such as urea, and in which the fraction of dialysis fluid is extracted through a branch conduit containing a pump. In accordance with this method, the total amount of used dialysis fluid is measured and the concentration of that substance in the extracted fraction is measured, and the total amount of that substance removed from the patient can then be calculated from these values. This invention is preferably intended for use in connection with hemodialysis, hemofiltration and hemodiafiltration.
摘要:
Apparatus for the preparation of fluids intended for medical use is disclosed, including a source of pure water and at least one cartridge or other vessel containing a powder which is to be dissolved in the water for preparation of the desired fluid. The apparatus includes a container such that the water and a powder or powder concentrate can be mixed and a concentrate provided in the container, and a recirculation circuit for recirculation of the water or concentrate solution into the container for further mixing of the water and powder or powder concentrate to prepare a concentrate having a predetermined concentration.
摘要:
Apparatus and methods are disclosed for controlling the flow of a fluid past a membrane in a dialyzer. The apparatus disclosed includes a fluid conduit for conducting the fluid both towards and away from the dialyzer, a flow constrictor for creating a pressure drop in the fluid conduit either upstream or downstream of the dialyzer, a pump for pumping the fluid through that conduit, and a pressure detector for measuring a pressure corresponding to that pressure drop so as to control the flow therein. The method disclosed includes flowing the fluid through an upstream fluid conduit to the dialyzer and through a downstream fluid conduit away from the dialyzer, producing a relatively constant flow in both the upstream and downstream fluid conduits, creating a pressure drop in one of the fluid conduits, pumping the fluid through that conduit, and measuring the pressure corresponding to that pressure drop so that the flow of the fluid in that conduit can be controlled thereby.
摘要:
Processes and apparatus for the removal of waste metabolites from metabolite-containing solutions are disclosed. The disclosed processes include alternatively adsorbing and desorbing the metabolites on a pair of adsorbent-containing columns, each column being maintained at a reduced temperature during adsorption and at an elevated temperature during desorption, with the columns being flushed subsequent to desorption and prior to their re-use for adsorption thereon. The disclosed apparatus includes a pair of adsorbent-containing columns, means for alternatively delivering the metabolite containing solution to each of the columns for alternate adsorption and desorption thereon, means for withdrawing the metabolite containing solution from each of the columns, means for alternately flushing the columns subsequent to desorption and prior to adsorption thereon, and means for alternately maintaining the columns at reduced temperatures during adsorption and at elevated temperatures during desorption so that the effectiveness of the adsorbent for adsorption is increased during adsorption at the reduced temperatures.A disposable tube set for use in connection with such a pair of adsorbent containing columns is also disclosed, including a flexible inlet tube including a pair of inlet branches for delivery of the metabolite containing solution to each of the columns, and a flexible outlet tube including a pair of outlet tube branches for connection with the outlet end of each of the columns.