U.S. patent application number 13/344445 was filed with the patent office on 2014-09-11 for blood-pumping device.
This patent application is currently assigned to King Saud University. The applicant listed for this patent is Abdulrahman Futayn Al-Harbi. Invention is credited to Abdulrahman Futayn Al-Harbi.
Application Number | 20140255229 13/344445 |
Document ID | / |
Family ID | 42831497 |
Filed Date | 2014-09-11 |
United States Patent
Application |
20140255229 |
Kind Code |
A9 |
Al-Harbi; Abdulrahman
Futayn |
September 11, 2014 |
Blood-pumping device
Abstract
A blood-pumping device comprises a cavity with a U-shaped wall
comprising two straight regions connected by an arch-shaped region
and a U-shaped tube aligned with the U-shaped wall of the cavity to
provide a support for the U-shaped tube, wherein the U-shaped tube
comprises two straight regions connected by a semicircular region.
The blood-pumping device further comprises an arm rotatable about a
center point of the semicircular region, wherein the arm holds two
wheels a distance from each other such that upon rotation of the
arm the wheels roll along the U-shaped tube while putting pressure
on the U-shaped tube, wherein the arch-shaped region of the
U-shaped wall of the cavity comprises a recessed portion so that
the wheels of the arm impose less pressure on the tube at the
recessed portion and upon rotation of the arm generates a pulsating
blood flow.
Inventors: |
Al-Harbi; Abdulrahman Futayn;
(Tabuk, SA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Al-Harbi; Abdulrahman Futayn |
Tabuk |
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SA |
|
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Assignee: |
King Saud University
Riyadh
SA
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20120171063 A1 |
July 5, 2012 |
|
|
Family ID: |
42831497 |
Appl. No.: |
13/344445 |
Filed: |
January 5, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/EP10/04124 |
Jul 6, 2010 |
|
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13344445 |
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Current U.S.
Class: |
417/477.3 |
Current CPC
Class: |
F04B 43/12 20130101;
A61M 1/1037 20130101; A61M 1/1005 20140204; F04B 43/1276 20130101;
A61M 1/1086 20130101; F04B 43/1238 20130101; F04B 43/1284 20130101;
A61M 1/10 20130101; A61M 1/1039 20140204; F04B 43/1253
20130101 |
Class at
Publication: |
417/477.3 |
International
Class: |
F04B 43/12 20060101
F04B043/12 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 6, 2009 |
SA |
SA109300439 |
Claims
1. A blood-pumping device, comprising: a cavity with an at least
partly U-shaped wall, the at least partly U-shaped wall comprises
two straight regions and an arch-shaped region connecting the two
straight regions; a U-shaped tube of deformable material for
carrying blood, which is at least partially aligned with the at
least partly U-shaped wall of the cavity to provide a support for
the U-shaped tube, wherein the U-shaped tube comprises a first and
a second straight region connected by a semicircular region; and an
arm being rotatable about a center point of the semicircular
region, wherein the arm holds a first and a second wheel in a
distance from each other such that upon rotation of the arm the
wheels roll along the U-shaped tube thereby exerting pressure on
the U-shaped tube, wherein the arch-shaped region of the U-shaped
wall of the cavity comprises a recess portion and wherein said
arch-shaped region and said recess portion are arranged such that
the pressure exerted by one of the wheels at the recess portion is
less than the pressure exerted by the one wheel on the U-shaped
tube at the arch-shaped region at a position outside said recess
portion, thereby generating a pulsating blood flow inside the
U-shaped tube upon rotation of the arm.
2. The blood-pumping device of claim 1, wherein the arm comprises a
first arm with the first wheel and a second arm with the second
wheel such that the arms are mounted with one end on an engine head
and the first and second wheels are mounted at an end opposite to
the one end of the arms.
3. The blood-pumping device of claim 1, further comprising a blank
space formed opposite to the recess portion of the U-shaped wall,
wherein the tube is not formed in the blank space.
4. The blood-pumping device of claim 1, wherein the recess portion
comprises a movable alignment piece, which is movable in the
direction away from the center point.
5. The blood-pumping device of claim 4, wherein the alignment piece
comprises an indicator for indicating the distance between the
alignment piece and the tube.
6. The blood-pumping device of claim 1, wherein the recess portion
comprises a depth profile adapted to a desired pressure profile of
the blood flow.
7. The blood-pumping device claim 1, further comprising a control
unit being configured to adjust the rotational velocity of the arm
to mimic a natural heart pulse.
8. Cardio-Pulmonary bypass device including a blood-pumping device
according claim 1.
9. The blood-pumping device of claim 2, further comprising a blank
space formed opposite to the recess portion of the U-shaped wall,
wherein the tube is not formed in the blank space.
10. The blood-pumping device of claim 2, wherein the recess portion
comprises a movable alignment piece, which is movable in the
direction away from the center point.
11. The blood-pumping device of claim 3, wherein the recess portion
comprises a movable alignment piece, which is movable in the
direction away from the center point.
12. The blood-pumping device of claim 2, wherein the recess portion
comprises a depth profile adapted to a desired pressure profile of
the blood flow.
13. The blood-pumping device of claim 3, wherein the recess portion
comprises a depth profile adapted to a desired pressure profile of
the blood flow.
14. The blood-pumping device of claim 4, wherein the recess portion
comprises a depth profile adapted to a desired pressure profile of
the blood flow.
15. The blood-pumping device of claim 5, wherein the recess portion
comprises a depth profile adapted to a desired pressure profile of
the blood flow.
16. The blood-pumping device claim 2, further comprising a control
unit being configured to adjust the rotational velocity of the arm
to mimic a natural heart pulse.
17. The blood-pumping device claim 3, further comprising a control
unit being configured to adjust the rotational velocity of the arm
to mimic a natural heart pulse.
18. The blood-pumping device claim 4, further comprising a control
unit being configured to adjust the rotational velocity of the arm
to mimic a natural heart pulse.
19. The blood-pumping device claim 5, further comprising a control
unit being configured to adjust the rotational velocity of the arm
to mimic a natural heart pulse.
20. The blood-pumping device claim 6, further comprising a control
unit being configured to adjust the rotational velocity of the arm
to mimic a natural heart pulse.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a 35 U.S.C. 371 National Stage
Application of International Application No. PCT/EP2010/004124,
filed Jul. 6, 2010, which claims priority to Saudi Arabian Patent
Application SA109300439, filed Jul. 6, 2009, the entire contents of
which both are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a blood-pumping device and
in particular to a Cardio-Pulmonary bypass device used in heart
surgery for providing an artificial heart.
BACKGROUND OF THE INVENTION
[0003] During heart surgery blood that under normal conditions is
pumped by the heart is during surgery streamed out of the body to a
pumping device (pumping machine), which is configured to provide a
blood circulation in the human body that is normally provided by
the natural heart. The artificial heart has to maintain the blood
flow during the surgery until the natural heart can be re-activated
after the end of the surgery.
[0004] The heart pulse is deactivated during a heart surgery and
the natural heart has completely stopped to pump blood so that the
physician can perform the surgical work. As the human body,
however, needs the blood to stay alive, the blood is circulated by
an external blood pumping device to provide a blood circulation
through the body and the blood-pumping device has to perform the
functions of the natural heart. In order to provide a pulsatile
blood flow existing systems aim to mimic the natural blood flow.
However, these systems do not provide the natural pulsating
behavior of the heart. For example, one available solution changes
the blood streaming from a continuous (non-pulsating) mode to a
pulsating mode by controlling the pumping speed, for example, by
alternating between a fast and a slow pumping speed. These systems
mimic the natural blood pulsing in the body during surgery, but do
not provide a real pulse wave. A further disadvantage of these
systems is that they need to change permanently the pumping speed
(e.g. the rotation velocity of a pumping engine) and thus these
systems do not work in a constant operational mode so that the wear
and tear of these devices is increased.
[0005] Therefore, there is a need for a blood-pumping device
providing a pulsating blood flow which comes as close as possible
to the natural pulsating blood flow while operating in a constant
operational mode. The object of the present invention is therefore
to provide a blood-pumping device generating a pulsating blood flow
by simple means.
SUMMARY OF THE INVENTION
[0006] In accordance with the present invention, a blood-pumping
device according to claim 1 solves the above-said problems. Claims
2 to 7 provide particular advantageous realizations of the pumping
device of claim 1. The invention also covers a Cardio-Pulmonary
bypass device according to claim 8.
[0007] The blood-pumping device according to the present invention
comprises a cavity with an at least partly U-shaped wall, the at
least partly U-shaped wall comprising at least two straight regions
and a arch-shaped (or curved) region connecting the two straight
regions as well as a U-shaped (or curved) tube of deformable
material, which is at least partially aligned with the at least
partly U-shaped wall of the cavity to provide a support for the
U-shaped tube, wherein the U-shaped tube comprises a first and a
second straight regions connected by a semicircular region or a
region essentially in the form of a segment of a circle. The
blood-pumping device further comprises an arm rotatable about a
center point of the semicircular region, wherein the arm holds a
first and a second wheel in a distance from each other such that
upon rotation of the arm the wheels roll along the U-shaped tube
while putting pressure on the U-shaped tube. The arch-shaped region
of the U-shaped wall of the cavity comprises a recess portion so
that the wheels of the arm impose less pressure on the tube at the
recess portion than on the tube outside the recess portion and upon
rotation of the arm a pulsating blood flow is generated. Thus, the
pulsating blood flow is generated by a decreasing pressure imposed
by the wheels when entering the recessed portion and an increasing
pressure when the wheels leave the recessed portion.
[0008] In further embodiments the arm comprises a first arm with
the first wheel and second arm with the second wheel such that the
arms are mounted with one end on an engine head and the first and
second wheels are mounted at an end that is opposite to the one end
of the arms. The blood pumping device may also comprise a blank
space formed opposite to the recess portion of the U-shaped wall
along which the tube does not extend. In further embodiments the
recess portion comprises a movable alignment piece, which is
movable in the direction away from the center point or is
optionally be formed with a depth profile adapted to a desired
pressure profile of the blood flow. The alignment piece may also
comprise an indicator for indicating the distance between the
alignment piece and the tube. The blood-pumping device may further
comprise a control unit being configured to adjust the rotational
velocity of the arm to mimic a natural heart pulse. Further
embodiments relate also to a Cardio-pulmonary bypass device
including said blood-pumping device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention will become apparent from the
following detailed description and the attached drawings in
which:
[0010] FIG. 1 shows a conventional blood-pumping device;
[0011] FIG. 2 shows a blood-pumping device according to the present
invention in closed position generating a continuous blood flow;
and
[0012] FIG. 3 shows the blood-pumping device of FIG. 2 in an open
position generating an intervallic pulsating blood flow.
DETAILED DESCRIPTION
[0013] FIG. 1 shows a head of a conventional blood pump providing
non-pulsating blood flow during a heart surgical operation, wherein
pulsating blood flow can be generated only by changing the speed of
the pumping engine. The shown blood pump comprises a pump head 11
with a cavity 20 (vacuum space) comprising an inverted U-shape with
a semicircular portion 25 and an opposite blank space 70. A tube 30
with an inlet 12 and an outlet 14 is provided for carrying the
blood coming from the body via the inlet 12 passing the cavity 20
and returning back to the human body via the outlet 14. The tube 30
comprises also a U-shape such that it is supported by the U-shaped
cavity 20, which provides also a backing for the tube 30. The tube
30 extends not along the blank space 70, but only along the U-shape
part of the internal wall of the cavity 20.
[0014] An engine of the pump (not shown in the figure) rotates an
engine head 40 around a middle point M (center point) of the
semicircular part of the U-shaped tube 30. At the engine head two
extended arms 50a, 50b are mounted such that upon rotation of the
engine both arms 50a, 50b circulate about the center point M. Each
arm 50a, 50b comprises a wheel 60a, 60b at its end portions away
from the center point M such that the wheels 60 put a pressure on
the tube 30 while rotating the engine head 40 together with the
arms 50a, 50b, because the tube 30 is backed by the internal wall
of the cavity 20. Thus, the tube 30 is placed in-between the wheels
60 on one hand and the internal vacuum wall 20 on the other hand
and is made of deformable material (e.g. a rubber material) to
deform under the pressure imposed by the wheels 60. By rotating the
engine head 40 the two arms are circulating and thereby putting
pressure on the tube 30, which varies with the rotation along the
tube 30 to pump the blood from the inlet 12 (from the body) to the
outlet 14 (to the body).
[0015] The blood pump as shown in FIG. 1 leads therefore to a
constant non-pulsating flow of blood, because at any time at least
one of the two wheels 60a, 60b is in contact with the tube 30,
thereby deforming the tube and pushing the blood inside the tube 30
towards the outlet 14 of the pump 11. Because the tube 30 extends
only along the U-shape shape of the cavity, but does not pass
through the blank space 70 of the inverted U-shape as shown in FIG.
1, this blank space 70 does not affect the constant non-pulsating
blood flow. If the first wheel 60a is inside this blank space 70,
the second wheel 60b continues to deform the tube 30 and hence
generating pressure on the blood contained in the tube 30 and,
therewith, transporting the blood towards the outlet 14.
[0016] Hence, the blood pump as shown in FIG. 1 can generate a
pulsating blood flow only by modulating the speed of the engine
head 40 to alternate between a slow and fast moving stage (i.e. the
angular velocity of the rotating arms about the center point M
varies). Therefore, only by changing the operation mode a blood
flow that mimics a pulsating flow during the surgery can be
provided by the system according to FIG. 1.
[0017] The present invention provides a new solution to achieve a
pulsating blood provided to a body during a surgery, without
interfering in the speed of the pumping engine.
[0018] FIG. 2 shows a head of a blood pump according to an
embodiment of the present invention usable during the heart
surgical operation, wherein a movable, adjustable component
(alignment piece) is at a closed position generating constant
non-pulsating blood flow in the same way as the device of FIG. 1.
If the adjustable component is in the open position, a pulsating
flow is generated as will be described in FIG. 3 The device of FIG.
2 has many features in common with the device of FIG. 1 so that a
repeated description of common components can be avoided here.
[0019] The blood-pumping device as shown in FIG. 2 again comprises
a cavity 20 with a U-shaped internal wall comprising two straight
regions and a arch-shaped region connecting the two straight
regions. The arch-shaped region comprises at least partially a
semicircular portion 25 as in FIG. 1. The blood-pumping device 10
comprises also a U-shaped tube 30 comprising a first and a second
straight region 32a and 32b connected by a semicircular region 34.
As in FIG. 1 the tube 30 is at least partially aligned with the
U-shaped internal wall of the cavity 20 to provide a support (i.e.
a backing) for the U-shaped tube 30 so that the tube 30 passes only
along the U-shape of the cavity 20, but is formed at the blank
space 70 of the inverted U-shape.
[0020] Moreover, the pumping device of FIG. 2 comprises also an arm
50 mounted rotatably about a central point M of the semicircular
region 34 of the tube 30, wherein the arm 50 holds a first and a
second wheel 60a, 60b in a distance from each other such that upon
rotation of the arm 50 the wheels 60 roll along the U-shapes tube
while providing a pressure on the U-shaped tube. The pumping device
10 comprises also a blood inlet 12 and a blood outlet 14 such that
upon a clockwise rotation of the arm 50 about the central point M
blood is carried from the inlet 12 to the outlet 14. Because at any
time at least one of the two wheels 60 are in contact with the tube
30, thereby deforming the tube 30, the rolling wheels 60 push and
pull blood in a clockwise direction around the semicircular part 34
of the tube 30 and a constant (non-pulsating) flow is generated. In
a further embodiment a counter-clockwise rotation of the arm 50 is
used to operate the pump in a reverse direction, i.e. pumping blood
from the outlet 14 to the inlet 12. Optionally, the arm 50 may
again comprise a first and a second arm 50a, 50b as described in
FIG. 1.
[0021] In contrast to the blood pumping device as shown in FIG. 1,
the blood-pumping device 10 of FIG. 2 comprises an alignment piece
80, which is movable and is adjusted to provide a semicircular
inner wall of the U-shaped internal wall of the cavity 20 so that
the tube 30 is in contact to the alignment piece 80 when the wheels
60 roll over the tube 30 on the side opposite to the alignment
piece 80 and thus generating pressure within the tube 30.
[0022] FIG. 3 shows the same head of the blood pump (blood-pumping
device 10) as in FIG. 2, but wherein the movable alignment piece 80
is moved into an open position providing an intervallic pulsating
blood flow used during heart surgical operations.
[0023] In comparison to the blood-pumping device of FIG. 2, the
alignment piece 80 is moved in a direction away from the center
point M so that between the alignment piece 80 and the tube 30 an
open space 85 appears and, in contrast to the situation as shown in
FIG. 2, the tube 30 is not supported anymore by the alignment piece
80. Therefore, when the wheels 60 roll on the tube 30 and reach the
position of the open space 85, the wheels 60 do not deform the tube
30 at this position and hence the pressure inside the tube 30 is
also relaxed. In particular, if for example the second wheel 60b
reaches the position opposite to the alignment piece 80 the first
wheel 60a is in region of the blank space 70 so that also the first
wheel 60a does not provide pressure on the tube 30. As consequence,
when the second wheel 60b passes the open space 85 and the first
wheel 60a passes the blank space 70 the blood pressure is relaxed.
When the second wheel 60b reaches again the point 87, where the
tube 30 is supported by the U-shaped internal wall of the cavities
20, the tube 30 will again deform and the blood pressure increases
again generating a pulsating blood flow. Thus, the rotating arm 50
generates alternating high and low pressure phases in the flow
(pulsating blood flow) by alternating between a low pressure state
when one of the wheel 60 is at the alignment piece 80 (or at the
open space 85) and a high pressure state when the one wheel 60 is
outside the alignment piece 80.
[0024] Therefore, embodiments of the present invention use two
techniques. In addition to the engine head as shown in FIG. 1 the
alignment piece 80 is added in the arch-shaped part of the cavity
20 opposite to the empty U-shaped blank space 70, which is movable
to be out of contact with the tube 30. An aligning bottom 90 can be
used to move up and down the alignment piece 80 and by adjusting
the alignment piece 80 away from the aligned position (where the
inner wall aligns to form a semicircular shape), the blood pressure
in the tube 30 decreases when wheels 60 simultaneously pass both,
the blank space 70 and the free space 85 (low pressure phase of the
pulsating blood flow). This arrangement provides the advantage that
a desired pulse frequency can easily be adjusted by the angular
velocity of the arm(s) 50 (pulse frequency is twice the number of
revolutions per minute, because each revolution generates two beats
of the artificial heart).
[0025] In further embodiments, the alignment piece 80 may be
provided with an indicator 12 indicating the distance from the
original position, which can be used during operation to further
improve the resulting blood pressure power. For example, when the
alignment piece 80 is very close to the tube 30 the difference
between the low pressure and the high pressure phases of the
pulsating blood is be very low, whereas with increasing distance of
the alignment piece from the tube 30 the difference between the low
pressure and high pressure phases of the blood increases.
[0026] Furthermore, upon revolving the engine head 40 the two arms
50 circulate around the center point M and the two connected wheels
60 put pressure on the blood tube 30, which is supported by the
internal wall of the cavity 20. Hence, the blood is pulled inside
the cavity 20 from the blood inlet 12 and pushed outside from the
blood outlet 14 towards the body during the surgery. When the
wheels 60 pass the blank space 70 the pressure is weakened, because
the other wheel is moving into the region of the alignment piece 80
(open space 85), whereby the pulsating pressure is mimicked.
[0027] In further embodiments in the cavity 20 a vacuum is
established improving the relaxation of the tube 30 after rolling
over with the wheels 60 (because the blood pressure inside the tube
30 can more easily expand the tube 30 if a vacuum is outside the
tube 30). In further embodiments the alignment piece 80 is replaced
by a recessed region in the wall, which may be not movable too. The
recessed region can be formed with a (depth) profile to generate a
desired pressure profile of the blood flow.
[0028] Therefore, embodiments of the present invention provide a
solution to achieve a pulsating flow of blood from and to a body
during surgery without interfering with the rotation speed in the
pumping engine. This effect is achieved by providing two portions
(two vacuum spaces), wherein the wheels do not put pressure on the
tube thereby releasing for a time period the pressure on the blood
inside the tube. The two vacuum spaces (open space 85 and blank
space 70) for the circulating arm 50 facing each other in the
blood-rotation head and make the blood pumping weak upon reaching
said spaces and get stronger again upon leaving said vacuum
spaces.
[0029] Hence, embodiments provide an external blood-pumping head
used in blood-pumping systems during surgeries. It contains an
inverted U-shape with a rotating head in the middle, with two arms
extended from the head. The arms barely touch the vacuum wall
internally. The blood tube passes adjacent to the mentioned vacuum
wall, between the vacuum wall and the arms. The arms put pressure
on the tube to push up the blood inside the tube from the human
body and re-pump it back during the rotation of the arms. The
mentioned vacuum wall has two vacuums opposing each other; one of
these vacuums has a moving, tightening wall integrating the shape
of the internal circle. It can be pulled out to reduce the blood
pressure during pumping the blood back to the body. This generates
a similar mimic of the natural heart pulses by moving the alignment
head and the two arms in circles inside the mentioned vacuum.
Further embodiments provide an external blood pumping head used in
blood pumping systems during surgeries. As said in the previous
embodiment, the mentioned alignment wall can be adjusted in
different grades.
* * * * *