54 results about "Blood withdrawal" patented technology

A dialysis catheter comprising a catheter body having a proximal portion, a distal portion, a first longitudinally extending central lumen configured to deliver blood, and at least three longitudinally extending lumens positioned radially of the central lumen and configured to withdraw blood from a patient. At least one blood delivery opening is formed in the distal portion of the catheter body and in fluid communication with the first lumen and configured for passage of blood therethrough. At least three blood withdrawal openings are formed in the outer wall of the catheter body, wherein each of the openings is in fluid communication with one of the at least three lumens and is configured for passage of blood from a patient

A method and apparatus for controlling blood withdrawal and infusion flow rate with the use of a pressure controller. The pressure controller uses pressure targets based upon occlusion limits that are calculated as a function of flow. The controller has the ability to switch from controlling withdrawal pressure to controlling infusion pressure based upon the detection of an occlusion. The controller distinguishes between partial and total occlusions of the withdrawal vein providing blood access. Depending on the nature of occlusion, the controller limits or temporarily reverses blood flow and, thus, prevents withdrawal vessel collapse or reverses blood flow to quickly infuse blood into the vessel without participation from operator.

Method and apparatus for the extracorporeal treatment of blood by utilizing a peripherally inserted dual lumen catheter assembly for the continuous removal and return of blood for renal replacement treatment, in particularly, treatment of congestive heart failure and fluid overload by ultrafiltration. A catheter is inserted in a peripheral vein and maneuvered upward through the vascular system to access the reservoir of blood in the large or great veins for continuous blood withdrawal and treatment. Air-tight connectors are incorporated in the catheter assembly to overcome the untoward effects of negative pressure in blood withdrawal.

An extracorporeal blood circuit including: a withdrawal conduit connectable to a coronary withdrawal catheter; a withdrawal pump connectable to the withdrawal conduit, wherein a pumping rate of the withdrawal pump determines a blood withdrawal rate from the coronary withdrawal catheter; a filter having an input connected to the withdrawal conduit and a blood output connected to an infusion conduit and a filtrate output connected to a filtrate conduit; a filtrate measurement device to determine an amount of filtrate removed from the blood in the filter; a fluid supplementation conduit providing a blood replacement fluid to at least one of the withdrawal conduit, filter and infusion conduit; a supplementation pump connectable to the fluid supplementation conduit, wherein a pumping rate of the supplementation pump determines a rate at which the blood replacement fluid flows into the blood flowing through the blood circuit, and a controller regulating the pumping rate of the supplementation pump such that the rate of the blood replacement fluid provides an amount of blood replacement fluid to the at least one of the withdrawal conduit, filter and infusion conduit so as to substantially match the amount of filtrate removed.

In the apparatus and method for monitoring a vascular access (6) of an extracorporeal circuit (5; 10) of a patient, a control and calculation unit (17) varies a flow rate of a blood pump (9) predisposed to cause blood to circulate in the extracorporeal circuit. The control and calculation unit receives the pressure values in the blood withdrawal line (5) and the blood return line (10) from two pressure sensors (8, 12); the pressure values are a series of different values of the blood flow rate. The control and calculation unit processes the data gathered by means of a mathematical model which describes the variation of pressure in the vascular access as a function of the flow rate, in order to determine the blood flow rate in the vascular access. The invention detects the presence and location of a stenosis at the vascular access of a patient subjected to a hemodialysis treatment.

The invention relates to a method and blood-withdrawal vessel for preparing blood samples for detecting homocysteine and / or total folate and is characterized in that the blood sample is brought into contact with (a) at least one reagent for lysis of the blood cells, (b) at least one inhibitor of the enzymes which produce and break down homocysteine, and optionally, (c) at least one acid.

Methods and systems for determining the concentration of one or more analytes from a sample such as blood or plasma are described. The systems described herein can be configured to withdraw a certain volume of sample from a source of bodily fluid, direct a first portion of the withdrawn sample to an analyte monitoring system and return a second portion of the sample to the patient. The analyte monitoring system can include an automated blood withdrawal system that is configured to withdraw blood from the patient's vasculature at low pressure and / or withdrawal rates so as to reduce or prevent contamination of the withdrawn fluid from the infusion fluids.