Method and device for the selective perfusion of fluids through blood vessels, controlled by the pressure in the blood vessels

Abstract

A method for selective perfusion of fluids through blood vessels is controlled by the pressure in the blood vessels. A tubing line open at the proximal end for the perfusion of fluids through a tissue region is introduced into a patient's blood vessel in which perfusion is to be performed. The vessel is sealed off from the line in the area of its proximal end, and fluid is pumped into the vessel. The method is characterized in that a specific set value for the internal pressure of the vessel is measured, and the perfused flow of fluid is regulated during pumping in such a way that the set value for the internal pressure of the vessel is kept as closely as possible.

1 . Method for the selective perfusion of fluids through blood vessels, controlled by the pressure in the blood vessels, in which method a tubing line ( 60 ) open at the proximal end for the perfusion of fluids through a tissue region is introduced into a patient's blood vessel ( 200 ) in which perfusion is to be performed, the vessel ( 200 ) is sealed off from the line ( 60 ) in the area of its proximal end, and the fluid is pumped into the vessel, characterized in that a specific set value for the internal pressure of the vessel is predefined, the internal pressure of the vessel is measured, and the perfused flow of fluid is regulated during pumping in such a way that the set value for the internal pressure of the vessel is kept as closely as possible.  
     
     
         2 . Method according to  claim 1 , characterized in that the fluid is pumped periodically at intervals into the vessel ( 200 ), the pumping intervals being synchronized with the patient's heartbeat.  
     
     
         3 . Method according to  claim 1 , characterized in that the fluid is pumped into the vessel ( 200 ) continuously.  
     
     
         4 . Method according to one of  claims 1  to  3 , characterized in that the vessel ( 200 ) is an artery which supplies blood to the tissue region which is to be protected.  
     
     
         5 . Method according to  claim 4 , characterized in that the set value of the internal pressure of the artery is chosen such that the nutritive perfusion is maintained.  
     
     
         6 . Method according to  claim 2 , characterized in that the vessel ( 200 ) is a vein, with the fluid being infused into the vein periodically via the tubing line ( 60 ), and with blood being suctioned from the vein via the tubing line ( 60 ).  
     
     
         7 . Method according to  claim 6 , characterized in that the pumping and suction intervals are synchronized with the patient's heartbeat.  
     
     
         8 . Method according to  claim 7 , characterized in that the set value for the internal pressure of the vein is determined by means of the fact that, with the vein sealed off and in the absence of venous blood flow, infusion is performed with the flow of fluid increasing at each pumping interval, and the internal pressure of the vein is measured, with the plateau pressure created in the vein in this process being chosen as the set value.  
     
     
         9 . Method according to  claim 7 , characterized in that the set value for the internal pressure of the vein is determined by means of the fact that, with the vein sealed off and in the presence of venous blood flow, the internal pressure of the vein is measured, with the plateau pressure of the peak venous pressures created in the vein in this process being chosen as the set value.  
     
     
         10 . Method according to one of  claims 1  to  9 , characterized in that the fluid to be infused is an oxygen carrier.  
     
     
         11 . Method according to  claim 10 , characterized in that the oxygen carrier is blood or a blood substitute.  
     
     
         12 . Method according to  claim 11 , characterized in that arterial blood is taken from the patient, and this blood is optionally cleaned, freed of air bubbles and perfused or retroinfused into the vessel ( 200 ).  
     
     
         13 . Method according to one of  claims 1  to  12 , characterized in that the fluid contains therapeutic or diagnostic active substances.  
     
     
         14 . Method according to one of  claims 6  to  13 , characterized in that the blood which has been suctioned in the suction intervals is defoamed, if appropriate, freed of air bubbles and returned to the patient via another vein ( 400 ).  
     
     
         15 . Device for the selective perfusion of a fluid through blood vessels, controlled by the pressure in the blood vessels, in particular for carrying out the method according to one of  claims 1  to  14 , with a tubing line ( 60 ) which can be introduced into a patient's blood vessel ( 200 ), is open at the proximal end and can be charged with a fluid under pressure which is to be pumped into the blood vessel ( 200 ), the proximal end being provided with an enlargeable sealing means ( 65 ) with which the vessel ( 200 ) can be sealed off from the line ( 60 ), and with means ( 50 ) for measuring the internal pressure of the blood vessel, characterized in that regulating means ( 30 ) are additionally provided, with the aid of which a control unit ( 10 ) regulates the perfused flow of fluid such that a defined set value for the internal pressure of the blood vessel is kept as constant as possible during pumping.  
     
     
         16 . Device according to  claim 15 , where the vessel ( 200 ) is a vein, characterized in that the line ( 60 ) is connected to a suction device ( 90 ) for blood from the patient's vein ( 200 ), and in that the control unit ( 10 ) receives signals from the patient's heartbeat and defines pumping and suction intervals which are synchronized with the patient's heart cycle.  
     
     
         17 . Device according to one of claims  15  and  16 , characterized in that the line ( 60 ) is a multi-lumen catheter, in particular an at least four-lumen catheter for retroinfusion, including an admission line ( 61 ) for the fluid, a suction line ( 62 ) for the suctioned blood, a measurement line ( 63 ) for determining the internal pressure of the vein, and a control line ( 64 ) for the enlargeable sealing means ( 65 ).  
     
     
         18 . Device according to  claim 15 , characterized in that the line ( 60 ) is a multi-lumen catheter, in particular an at least three-lumen artery catheter for perfusion, including an admission line ( 61 ) for the fluid, a measurement line ( 63 ) for determining the internal pressure of the artery, and a control line ( 64 ) for the enlargeable sealing means ( 65 ).  
     
     
         19 . Device according to one of  claims 15  to  18 , characterized in that the sealing means ( 65 ) is a pressure-controlled, inflatable balloon.  
     
     
         20 . Device according to one of  claims 18  to  19 , characterized in that the measurement line ( 63 ) communicates at one end with the inside of the vessel and has a pressure sensor ( 51 ) at its other end.  
     
     
         21 . Device according to one of  claims 15  to  19 , characterized in that the means ( 50 ) for measuring the venous pressure comprise a pressure sensor ( 52 ) arranged at the proximal end of the line ( 60 ), which pressure sensor ( 52 ) is connected to the control unit ( 10 ).  
     
     
         22 . Device according to one of  claims 15  to  21 , characterized in that the regulating means ( 30 ) for the perfused flow of fluid comprise a flow regulator cooperating with the line ( 60 ).  
     
     
         23 . Device according to  claim 22 , characterized in that the admission line ( 60 ,  61 ) is formed by an elastically yielding tubing in the area of the flow regulator ( 30 ), the flow regulator ( 30 ) comprising a clamping member ( 31 ) which is driven by an electric motor and which presses the elastic tubing together to a greater or lesser extent and so controls the flow of the fluid into the blood vessel.  
     
     
         24 . Device according to one of  claims 15  to  23 , characterized in that the distal end of the admission line ( 60 ,  61 ) is connected to a fluid reservoir ( 81 ) which is under pressure and which has a pressure sensor ( 82 ) for monitoring the pressure in the reservoir ( 81 ).  
     
     
         25 . Device according to  claim 24 , characterized in that the blood taken from an artery ( 300 ) of the patient is fed to the reservoir ( 81 ) via a roller pump ( 83 ).  
     
     
         26 . Device according to one of  claims 16  to  25 , characterized in that the suction device ( 90 ) has a vacuum pump ( 92 ) and a container ( 93 ) for the suctioned blood.  
     
     
         27 . Device according to one of  claims 16  to  26 , characterized in that the suction device ( 90 ), a reservoir ( 94 ), a roller pump ( 95 ) and an air trap ( 96 ) are connected to one another in order to deliver the suctioned blood, cleaned, to a vein ( 400 ) of the patient.