Ex Parte Obrigkeit

Patent Trial and Appeal Board

Apr 18, 2013

12108579 (P.T.A.B. Apr. 18, 2013)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
12/108,579 04/24/2008 Kevin G. Obrigkeit 0173(17420) 1897
46909 7590 04/19/2013
TERUMO CARDIOVASCULAR SYSTEMS CORPORATION
ATTN: GAEL DIANE TISACK
6200 JACKSON ROAD
ANN ARBOR, MI 48103
EXAMINER
SCHELL, LAURA C
ART UNIT PAPER NUMBER
3767
MAIL DATE DELIVERY MODE
04/19/2013 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte KEVIN G. OBRIGKEIT
__________

Appeal 2011-005303
Application 12/108,579
Technology Center 3700
__________

Before ERIC GRIMES, FRANCISCO C. PRATS, and
JACQUELINE WRIGHT BONILLA, Administrative Patent Judges.

GRIMES, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a single-
lumen, multi-stage cannula. The Examiner has rejected the claims as
obvious. We have jurisdiction under 35 U.S.C. § 6(b). We reverse.
STATEMENT OF THE CASE
The Specification discloses a “venous return cannula … generating an
even flow from multiple inlets along the length of the cannula” (Spec. 1:15-
17). Figure 3 of the Specification is shown below:
Appeal 2011-005303
Application 12/108,579

2

Figure 3 shows a multi-stage cannula “comprised of separately molded
pieces for first stage 11, second stage 12, and proximal tube 13” (id. at 5:25-
26).
Claims 1-16 are on appeal. Claim 1 is representative and reads as
follows:
1. A single-lumen, multi-stage cannula comprising:
a first stage comprising a longitudinal tubular tip having a first
plurality of fenestrations disposed at a distal end of the tip for supplying
fluid from a first region outside the cannula to provide an axial flow at a
proximal end of the tip;
a second stage coaxial with the first stage comprising a nozzle section
having an outer lumen wall and an inner annular wall, wherein a central
passage is disposed within the inner annular wall, wherein the central
passage continues the axial flow from the first stage, wherein a plurality of
outer passages are disposed between the outer lumen wall and the inner
annular wall so that the inner annular wall isolates the central passage from
the outer passages, wherein the outer lumen wall includes a plurality of
second fenestrations, wherein each second fenestration supplies fluid from a
second region outside the cannula to a respective outer passage, and wherein
the outer passages have respective outlets arranged to provide an injected
flow substantially parallel to the axial flow; and
a proximal tube coaxial with the second stage and having a central
lumen, wherein an initial portion of the central lumen continues the axial
flow and receives the injected flow annularly injected around and
Appeal 2011-005303
Application 12/108,579

3
substantially parallel with the axial flow, and wherein a proximal end of the
central lumen delivers a drainage output of the cannula comprising the axial
flow and injected flow together.

The Examiner has rejected claims 1-12 under 35 U.S.C. § 103(a) as
obvious in view of Difiore,
1
and has rejected claims 13-16 as obvious in
view of Difiore and Medtronic.
2
The same issue is dispositive for both of
these rejections.
The Examiner finds that Difiore discloses a cannula comprising the
first and second stages recited in claim 1 but does not disclose a specific
embodiment in which the fluid flow in those stages are merged into a single
lumen and flow together (Answer 4-5). The Examiner concludes, however,
that it would have been obvious “to have modified Difiore‟s dual lumen
catheter … such that both sets of fenestrations fed into a single lumen, as
Difiore teaches that this is a possible modification (paragraph [0026]) and
this would provide a drainage cannula that is able to drain at multiple
positions along its length and therefore provide a more efficient drainage”
(id. at 5).
Appellant argues that Difiore‟s paragraph 26, which was cited by the
Examiner, only refers to applying Difiore‟s inventive catheter tip to both
single and dual lumen catheters (Appeal Br. 6). Appellant argues that
Difiore‟s single-lumen catheter invention is shown in its Figures 1A-1D, and
does not result in the product defined by claim 1 (id.). Appellant also argues
that “Difiore teaches away from modifying a dual-lumen catheter such that

1
Difiore et al., US 2006/0004316 A1, published Jan. 5, 2006.
2
Medtronic, MC2X, Three Stage Venous Cannulae, Performance Under
Pressure (2005).
Appeal 2011-005303
Application 12/108,579

4
both sets of fenestrations feed into a single lumen” (id.) because its dual-
lumen catheter is a hemodialysis catheter designed to keep “dirty blood” and
processed blood separate, where modification to a single lumen would result
in mixing the dirty and processed blood (id. at 6-7).
We agree with Appellant that the Examiner has not adequately
explained what would have led a skilled artisan to modify Difiore‟s cannula
to include a proximal tube “having a central lumen, wherein an initial
portion of the central lumen continues the axial flow [from the first stage]
and receives the injected flow [from the second stage],” as recited in claim 1.
Difiore discloses “a catheter having a distal tip designed to decrease the
outflow velocity of fluid being delivered by the catheter” (Difiore 1, ¶ 0009).
Figure 1A of Difiore is shown below:

Figure 1A shows one embodiment of Difiore‟s catheter tip.
Difiore discloses that a “low outflow profile catheter tip may be
implemented in a catheter having two or more lumens. For example, a low
outflow profile catheter tip may be utilized in a hemodialysis catheter.” (Id.
at 2, ¶ 0010.) Figure 2A of Difiore is shown below:
Appeal 2011-005303
Application 12/108,579

5

Figure 2A shows “a dual lumen catheter 42 having a co-axial lumen design”
(id. at 4, ¶ 0033). Difiore discloses that the “bullet nose 44 has a radial array
of openings 8 angled to intersect with the center (i.e., inner) lumen 22 of the
catheter…. The annular (i.e., outer) lumen 46 of the catheter terminates in a
radial array of tapered slots 48 on [the] outer circumference at the distal
portion 50 of the catheter.” (Id.)
Difiore discloses that the “multi lumen catheters may be configured as
a hemodialysis catheter with one lumen utilized for removing „dirty blood‟
from the vein and the second lumen utilized to deliver the processed blood
back into circulation” (id. at 5, ¶ 0037). Difiore states that using its catheter
tip in a hemodialysis catheter decreases the outflow velocity of blood being
infused, and thereby “decrease[s] the mixing of newly infused blood with
the existing venous blood (i.e., „dirty blood‟), thus reducing the recirculation
of the processed blood” (id. at 2, ¶ 0010). Difiore also states that
while a dual lumen hemodialysis catheter is used herein as an
example application to illustrate the functionality of the
different aspects of the invention disclosed herein, it should be
understood that embodiments of the present invention may be
applied to a variety of catheters, including catheters having a
single lumen, and catheters having two or more lumens.

Appeal 2011-005303
Application 12/108,579

6
(Id. at 3, ¶ 0026.)
Thus, Difiore discloses a catheter tip that may be used in single lumen
or multiple lumen catheters to reduce the velocity of fluid outflow. Difiore
also discloses that using the catheter tip in dual lumen catheters such as
hemodialysis catheters is advantageous because it decreases mixing of the
processed blood being infused into the patient with “dirty blood” being
removed from the patient. Difiore‟s discussion of dual lumen catheters is
therefore limited to catheters in which the two lumens remain separate,
rather than merging as in claim 1. The Examiner has not pointed to anything
in Difiore, or within the knowledge of those skilled in the art, that would
have provided a reason to modify the dual lumen catheter shown in Difiore‟s
Figure 2A in the manner required by claim 1; specifically, to merge the flow
of the inner and outer lumens into a single flow in a central lumen. Thus, we
reverse the rejection of independent claim 1 and dependent claims 2-15 as
being obvious in view Difiore.
The Examiner has also rejected claims 13-16 as obvious in view of
Difiore and Medtronic. Independent claim 13, like claim 1, requires a first
stage with a tubular tip, a second stage nozzle section, and a proximal tube.
Claim 13 also requires a third stage nozzle section between the second stage
nozzle section and the proximal tube. Since, as explained above, we
conclude that the Examiner has not adequately explained why it would have
been obvious to modify Difiore‟s dual lumen catheter to merge the flow of
the inner and outer lumens into a single flow in a central lumen, we also
reverse the rejection of claim 13 and dependent claims 14-16 as being
obvious in view Difiore and Medtronic.
Appeal 2011-005303
Application 12/108,579

7
SUMMARY
We reverse the rejection of claims 1-16 under 35 U.S.C. § 103(a).

REVERSED

cdc