Multichannel catheter

Abstract

A single, multichannel catheter useful for extracorporeal circulation of blood to a patient undergoing cardiovascular treatments or surgery. The catheter has three independent channels and an expandable balloon at one end of the catheter. The first channel is the largest and is of a size that allows for delivery of blood to a patient in an amount sufficient to maintain the patient's metabolism and perfusion throughout the treatment or surgery. A second channel, smaller than the first, is integrated into the wall of the first channel and is suitable for delivering a biologically active fluid (e.g., for cardioplegia) to the heart and/or venting the left heart. A third channel, also smaller than the first, is integrated into the wall of the first channel and suitable for delivering a fluid to the balloon for its expansion when positioned in the ascending aorta to occlude the flow of blood to the heart. It is important that the first channel accounts for at least about 70% of the total channel volume. The catheter provides an improved means of performing cardiovascular surgery on a patient using a cardiopulmonary machine for extracorporeal circulation of blood. The catheter is particularly useful for cardiac surgery. The multichannel catheter is best prepared using an extrusion molding technique.

What is claimed is:  
     
         1 . A multichannel catheter having distal and proximal ends, which catheter comprises 
 a central, first channel (i) extending substantially the length of the catheter, (ii) comprising at least about seventy percent of the available channel volume of the catheter, (iii) being defined by the wall of the catheter, and (iv) being closed at its distal end;    a second channel (i) extending substantially the length of the catheter parallel to said first channel but independent thereof, (ii) being integrated into the wall of the first channel, and (iii) being open at its distal end;    a third channel (i) extending substantially the length of said catheter parallel to said first and second channels but independent thereof, (ii) comprising, in combination with the second channel, not more than about thirty percent of the available channel volume of the catheter, and (iii) being integrated into the wall of the first channel and spaced from the second channel;    a plurality of openings in the wall of the catheter near the distal end of said catheter and communicating only with said first channel; and    an inflatable means integrated into the distal end of the catheter between said first channel openings and said second channel distal opening and with the distal opening of said third channel in fluid communication with the interior of the inflatable means, wherein the catheter is of a size suitable for insertion into a blood vessel of a mammal.    
     
     
         2 . The catheter of  claim 1  wherein the outflow capacity of the plurality of openings communicating with said first channel exceeds the inflow capacity into the first channel.  
     
     
         3 . The catheter of  claim 2  wherein a majority of the plurality of openings are elongate with the length of each elongate opening being parallel to the length of the catheter.  
     
     
         4 . The catheter of  claim 1  wherein the catheter is of a length that is sufficient to allow insertion into a femoral artery and positioning such that the distal end of the catheter is located in the ascending aorta such that the openings communicating with the first channel are positioned substantially adjacent the great arteries.  
     
     
         5 . The catheter of  claim 1  wherein the catheter is made using an extrusion technique.  
     
     
         6 . The catheter of  claim 1  wherein markings are positioned near the proximal end of the catheter to mark the distance from the distal end of the catheter.  
     
     
         7 . A process of preparing a multichannel catheter that is of a size suitable for insertion into a blood vessel of a mammal, which process comprises 
 (A) extrusion molding a catheter having distal and proximal ends wherein the catheter comprises 
 (1) a central, first channel (a) extending substantially the length of the catheter, (b) comprising at least about seventy percent of the available channel volume of the catheter, and (c) being defined by the wall of the catheter;  
 (2) a second channel (a) extending substantially the length of the catheter parallel to said first channel but independent thereof and (b) being integrated into the wall of the first channel;  
 (3) a third channel (a) extending substantially the length of said catheter parallel to said first and second channels but independent thereof, (b) comprising, in combination with the second channel, not more than about thirty percent of the available channel volume of the catheter, and (c) being integrated into the wall of the first channel and spaced from said second channel.  
   
     
     
         8 . The process of  claim 7  that comprises in addition to: 
 (A) forming a plurality of openings in the wall of the catheter near the distal end of said catheter and communicating only with said first channel;  
 (B) integrating an inflatable means into the distal end of the catheter positioned distal to said first channel openings so that the inflatable interior of the means in fluid communication with said third channel through an opening in the wall of the catheter, and  
 (C) forming at least one opening positioned distal to the inflatable means and communicating with said second channel;  
 (D) closing the distal end of said first channel.  
 
     
     
         9 . The process of  claim 8  wherein the outflow capacity of said plurality of openings communicating with said first channel exceeds the inflow capacity of the first channel.  
     
     
         10 . The process of  claim 9  wherein a majority of the plurality of opening are elongate with the length being parallel to the length of the catheter.  
     
     
         11 . The process of  claim 8  wherein the catheter is of a length that is sufficient to allow insertion into a femoral artery and positioning such that the distal end of the catheter may be located in the ascending aorta such that the openings communicating with the first channel are positioned substantially adjacent the great arteries.  
     
     
         12 . A process for providing oxygen-rich blood to a patient's arterial circulation while providing a biologically active fluid to the heart of the subject, which process comprises 
 positioning a multichannel catheter having a proximal end and a distal end in the patient's aorta, wherein said multichannel catheter comprises 
 (a) a central, first channel (i) extending substantially the length of the catheter, (ii) comprising at least about seventy percent of the available channel volume of the catheter, (iii) being closed at the distal end of said catheter and (iv) being defined by the wall of the catheter;  
 (b) a second channel (i) extending substantially the length of the catheter parallel to said first channel but independent thereof and (ii) being integrated into the wall of the first channel;  
 (c) a third channel (i) extending substantially the length of said catheter parallel to said first and second channels but independent thereof, (ii) comprising, in combination with the second channel, not more than about thirty percent of the available channel volume of the catheter, and (iii) being integrated into the wall of the first channel and spaced from said second channel;  
 (d) a plurality of openings near the distal end of said catheter communication only with said first channel;  
 (e) at least one opening at the distal end of the catheter communicating with said second channel;  
 (f) an inflatable means (i) integrated into the distal end of the catheter between said first channel openings and said second channel opening and (ii) communicating with said third channel through an opening in the wall of the catheter;  
   providing a source of oxygen-rich blood to the proximal end of said first channel;    providing a source of biologically active fluid to the proximal end of said second channel;    providing a source of fluid for inflating said inflatable means to the proximal end of said third channel;    positioning said multichannel catheter within the subject's blood circulatory system such that the distal end of said catheter is positioned in the ascending aorta so that the first channel openings are located upstream of the inflatable means, the inflatable means is located on the cephalid side of the aortic valve and the distal end of the second channel is located downstream of the inflatable means and proximate the aortic valve;    optionally inflating said inflatable means to block the flow of blood to the heart;    pumping biologically active fluid into the heart;    pumping oxygen-rich blood through said first channel out the first channel openings at rate sufficient to maintain the subject's metabolism and perfusion;    optionally performing cardiovascular surgery on the heart as needed; and    maintaining the circulatory support for said subject as needed.    
     
     
         13 . The process of  claim 12 , wherein the biologically active fluid is a cardioplegia solution and the cardiovascular surgery is cardiac surgery.  
     
     
         14 . A process for performing cardiobvascular surgery, which process comprises 
 inserting at least one cannula into the mammal's peripheral veins with positioning so the distal open end of the cannula is adjacent the vena cava regions of the mammal's heart and the proximal end of the cannula is attached to a cardiopulmonary machine through a pump wherein said cardiopulmonary machine comprises a blood oxygenation means fluidly connected to said pump,    inserting a multichannel catheter having a proximal end and a distal end into a femoral artery, wherein said multichannel catheter comprises 
 (a) a central, first channel (i) extending substantially the length of the catheter, (ii) comprising at least about seventy percent of the available channel volume of the catheter, (iii) being closed at the distal end of said catheter and (iv) being defined by the wall of the catheter;  
 (b) a second channel (i) extending substantially the length of the catheter parallel to said first channel but independent thereof, and (ii) being integrated into the wall of the first channel;  
 (c) a third channel (i) extending substantially the length of said catheter parallel to said first and second channels but independent thereof, (ii) comprising, in combination with the second channel, not more than about thirty percent of the available channel volume of the catheter, and (iii) being integrated into the wall of the first channel and spaced from said second channel;  
 (d) a plurality of openings near the distal end of said catheter communication only with said first channel;  
 (e) at least one opening at the distal end of the catheter communicating with said second channel;  
 (f) an inflatable means (i) integrated into the distal end of the catheter between said first channel openings and said second channel opening and (ii) communicating with said third channel through an opening in the wall of the catheter;  
   positioning said multichannel catheter within the subject's blood circulatory system such that the distal end of said catheter is positioned in the ascending aorta such that the first channel openings are located upstream of the inflatable means and proximate the great arteries, said inflatable means is located on the cephalid side of the aortic valve and the distal end of the second channel is located downstream of the inflatable means and proximate the aortic valve;    providing a source of oxygenated blood from the cardiopulmonary machine to the proximal end of said first channel;    providing a source of biologically active fluid to the proximal end of said second channel;    providing a source of fluid for inflating said inflatable means to the proximal end of said third channel;    inflating said inflatable means to block the flow of blood to the heart;    optionally pumping cardioplegia solution into the heart to arrest the mammal's heart;    pumping oxygen-rich blood through said first channel out the first channel openings at rate sufficient to maintain the subject's metabolism and perfusion;    removing oxygen depleted from the mammal's vena cavae regions through the femoral vein cannula by applying a negative pressure using the centrifugal pump;    performing cardiovascular surgery as needed; and    maintaining the circulatory support for said subject as needed.    
     
     
         15 . A single multichannel catheter useful for extracorporeal circulation of blood to a patient undergoing cardiovascular surgery wherein the catheter comprises 
 at least three independent channels and an expandable balloon at one end of the catheter,    a first largest channel of a size to allow delivery of an amount of blood to the patient that is sufficient to support the patient metabolism and perfusion throughout the surgery,    a second channel, smaller than the first channel and integrated into the wall of the first channel, said second channel suitable for (a) delivering cardioplegia solution to the heart and (b) venting the left heart, and    a third channel also smaller than the first channel and integrated into the wall of the first channel said third channel suitable for delivery of a fluid to the balloon for its expansion when positioned in the ascending aorta to occlude the flow of blood.    
     
     
         16 . The catheter of  claim 15  of a length sufficient to be inserted throughout a femoral artery and positioned so that the balloon is positioned in the ascending aorta.  
     
     
         17 . The catheter of  claim 15  wherein the blood is delivered to the patient through openings in the wall of the first channel that are upstream of the balloon and the cardioplegia solution is delivered and the left heart is vented through an opening in the second channel that is downstream of the balloon.  
     
     
         18 . In a method for performing cardiovascular surgery on a patient using a cardiopulmonary machine for extracorporeal circulation of blood, the improvement that comprises using a single, multichannel catheter for the extracorporeal circulation wherein the multichannel catheter comprises 
 at least three independent channels and an expandable balloon at the distal end of the catheter,    a first largest channel of a size to allow delivery of an amount of blood to the patient that is sufficient to support the patient metabolism and perfusion throughout the surgery,    a second channel, smaller than the first channel and integrated into the wall of the first channel, said second channel suitable for (a) delivering cardioplegia solution to the heart and (b) venting the left heart, and    a third channel also smaller than the first channel and integrated into the wall of the first channels, said third channel suitable for delivery of a fluid to the balloon for its expansion when positioned in the ascending aorta to occlude the flow of blood.    
     
     
         19 . The method of  claim 18  wherein the blood is delivered to the patient through openings in the wall of the first channel that are upstream of the balloon and the cardioplegia solution is delivered through the second channel out an opening that is downstream of the balloon.  
     
     
         20 . The method of  claim 19  wherein the surgery is open-chest surgery and the catheter is inserted through the patient's aorta or one of the great arteries and positioned so that the balloon in located in the ascending aorta to occlude the flow of blood to the heart.  
     
     
         21 . The method of  claim 19  wherein the surgery is minimally invasive surgery and the catheter is inserted into the patient through the patient's femoral artery and positioned so that the balloon in located in the ascending aorta to occlude the flow of blood to the heart.  
     
     
         22 . A method of delivering a biologically active agent to a subject in need thereof, which method comprises administering the agent using a single, multichannel catheter for the extracorporeal circulation wherein the multichannel catheter comprises 
 at least three independent channels and an expandable balloon at the distal end of the catheter,    a first largest channel of a size to allow delivery of an amount of blood to the patient that is sufficient to support the patient metabolism and perfusion throughout the surgery,    a second channel, smaller than the first channel and integrated into the wall of the first channel, said second channel suitable for (a) delivering cardioplegia solution to the heart and (b) venting the left heart, and    a third channel also smaller than the first channel and integrated into the wall of the first channels, said third channel suitable for delivery of a fluid to the balloon for its expansion when positioned in the ascending aorta to occlude the flow of blood.    
     
     
         23 . The method of  claim 21  wherein the agent is a cardioplegia solution delivered through the second channel to the heart of a patient in need thereof.