Method of converting a femoral venous cannula
A venous drainage cannula, catheter, or other device is in certain embodiments convertible or adjustable for application in cardiac surgery procedures involving cardiopulmonary bypass. Such a convertible cannula device can be modified, for example, for use as both a multi-stage cannula and a bi-caval cannula, so that the same device can be used in multiple different procedures where one or the other cannula type is needed. Such convertible cannula or other device can simplify and reduce a number of parts needed for a bypass procedure, by providing one adjustable and versatile device to serve multiple functions where different cannulae are traditionally required. Various embodiments further provide cannula devices where a variety of different hole or opening arrangements and configurations can be achieved, to adapt to various different procedures.
1 . A method of heart surgery on a patient, the method comprising:
readying a cannula for insertion in the patient's vasculature, the cannula having a distal end, a proximal end, and a longitudinal axis extending between the distal end and the proximal end, and the cannula having a length sufficient to extend from outside the body to at least the superior vena cava and having:
a distal section at the distal end, the distal section comprising an outer wall and having a plurality of spaced openings in the outer wall distributed circumferentially and longitudinally therearound and open to an inner space within the cannula;
a central section in series with the distal section along the longitudinal axis, the central section comprising an outer wall and having a plurality of spaced openings in the outer wall distributed circumferentially and longitudinally therearound and open to the inner space within the cannula; and
a proximal section in series with the central section along the longitudinal axis on a side of the central section opposite the distal section, the proximal section comprising an outer wall and having a plurality of spaced openings in the outer wall distributed circumferentially and longitudinally therearound and open to the inner space within the cannula;
inserting the distal end of the cannula into the femoral vein at or near the groin or thigh area;
advancing the cannula through the femoral vein and up through the inferior vena cava towards the heart until a conversion position is reached wherein the distal section is located in the superior vena cava, the central section is located in the right atrium, and the proximal section is located in the inferior vena cava, wherein the central section is sufficiently long to extend from the inferior vena cava to the superior vena cava, so that the openings in distal and proximal sections are only positioned in the inferior and superior venae cava, and not in the right atrium;
establishing the patient on cardiopulmonary bypass, including suctioning blood inward through the openings in the distal section, central section, and proximal section into the inner space within the cannula, and drawing the blood longitudinally through the cannula inner space to a cardiopulmonary bypass machine;
performing a procedure within the left atrium and/or the left ventricle;
while the cannula is in the conversion position, converting the cannula from a multi-stage cannula to a bi-caval cannula by closing the openings in the central section without changing the cannula location, and performing a procedure within the right atrium and/or the right ventricle while continuing to draw the blood longitudinally through the cannula to the cardiopulmonary bypass machine.
2 . The method of claim 1 , wherein the cannula includes a shutter wall member slidingly disposed along the central section, the shutter wall member having a plurality of apertures in between solid wall portions, wherein the apertures of the shutter wall member are aligned with the openings in the central section to enable the cannula to function as a multi-stage cannula, and the solid wall portions are aligned with and occlude the openings in the central section to enable the cannula to function as a bi-caval cannula.
3 . The method of claim 2 , wherein in a first position of the shutter wall member relative to the cannula configuration, the apertures are aligned with the openings in the central section, and in a second position of the shutter wall member the wall portions are aligned with and occlude the openings in the central section, while the openings in the distal section and the proximal section remain open to the inner space.
4 . The method of claim 3 , wherein the wall portions are longitudinal strips, and the shutter wall member rotates circumferentially around the longitudinal axis to move between the first position and the second position.
5 . The method of claim 3 , wherein the wall portions are ring-shaped strips, and the shutter wall member moves longitudinally towards either the distal end or the proximal end of the cannula to move between the first position and the second position.
6 . The method of claim 2 , wherein the shutter wall member is configured to be more rigid than the distal, central and proximal sections of the cannula.
7 . The method of claim 2 , wherein the shutter wall member and the central section of the cannula are configured to be more rigid than the distal and proximal sections of the cannula.
8 . The method of claim 2 , wherein the shutter wall member is located within the outer wall of the central section.
9 . The method of claim 2 , wherein the openings in the distal and proximal sections are circular, and the openings in the central section are rectangular.
10 . The method of claim 1 , wherein the procedure within the right atrium and/or the right ventricle comprises a tricuspid valve replacement or repair.
11 . A method of heart surgery on a patient, the method comprising:
readying a cannula for insertion in the patient's vasculature, the cannula having a distal end, a proximal end, and a longitudinal axis extending between the distal end and the proximal end, and the cannula having a length sufficient to extend from outside the body to at least the superior vena cava and having:
a distal section at the distal end, the distal section comprising an outer wall and having a plurality of spaced openings in the outer wall distributed circumferentially and longitudinally therearound and open to an inner space within the cannula;
a central section in series with the distal section along the longitudinal axis, the central section comprising an outer wall and having a plurality of spaced openings in the outer wall distributed circumferentially and longitudinally therearound and open to the inner space within the cannula;
a proximal section connected to the central section distally along the longitudinal axis on a side of the central section opposite the distal section, the proximal section comprising an outer wall and having a plurality of spaced openings in the outer wall distributed circumferentially and longitudinally therearound and open to the inner space within the cannula; and
a shutter wall member slidingly disposed within the inner space, the shutter wall member having a plurality of apertures in between solid wall portions;
inserting the distal end of the cannula into the femoral vein at or near the groin or thigh area;
advancing the cannula through the femoral vein and up through the inferior vena cava towards the heart until a conversion position is reached wherein the distal section is located in the superior vena cava, the central section is located in the right atrium, and the proximal section is located in the inferior vena cava, wherein the central section is sufficiently long to extend from the inferior vena cava to the superior vena cava, so that the openings in distal and proximal sections are only positioned in the inferior and superior venae cava, and not in the right atrium;
establishing the patient on cardiopulmonary bypass, including suctioning blood inward through the openings in the distal section, central section, and proximal section into the inner space within the cannula, and drawing the blood longitudinally through the cannula inner space to a cardiopulmonary bypass machine;
performing a procedure within the left atrium and/or the left ventricle;
while the cannula is in the conversion position, converting the cannula from a multi-stage cannula to a bi-caval cannula by closing the openings in the central section without changing the cannula location, wherein in a first position of the shutter wall member the apertures are aligned with the openings in the central section to enable the cannula to function as a multi-stage cannula, and after moving the shutter wall member from the first position to a second position, the solid wall portions are aligned with and occlude the openings in the central section to enable the cannula to function as a bi-caval cannula, while the openings in the distal section and the proximal section remain open to the inner space, and performing a procedure within the right atrium and/or the right ventricle while continuing to draw the blood longitudinally through the cannula to the cardiopulmonary bypass machine.
12 . The method of claim 11 , wherein the wall portions are longitudinal strips, and the shutter wall member rotates circumferentially around the longitudinal axis to move between the first position and the second position.
13 . The method of claim 11 , wherein the wall portions are ring-shaped strips, and the shutter wall member moves longitudinally towards either the distal end or the proximal end of the cannula to move between the first position and the second position.
14 . The method of claim 11 , wherein the shutter wall member is configured to be more rigid than the distal, central and proximal sections of the cannula.
15 . The method of claim 11 , wherein the shutter wall member and the central section of the cannula are configured to be more rigid than the distal and proximal sections of the cannula.
16 . The method of claim 11 , wherein the openings in the distal and proximal sections are circular, and the openings in the central section are rectangular.
17 . The method of claim 11 , wherein the openings in the central section are rectangular.
18 . The method of claim 17 , wherein the wall portions are longitudinal strips, and the shutter wall member rotates circumferentially around the longitudinal axis to move between the first position and the second position.
19 . The method of claim 17 , wherein the wall portions are ring-shaped strips, and the shutter wall member moves longitudinally towards either the distal end or the proximal end of the cannula to move between the first position and the second position.
20 . The method of claim 11 , wherein the procedure within the right atrium and/or the right ventricle comprises a tricuspid valve replacement or repair.