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22 Single-Team taTME
231
present, the taTME effort will inevitably fail.
This is why it is crucial to ensure the environment
at the local institution is amenable to a singleteam program prior to advocating for it. Both surgeon and institution should act with extreme
caution when considering taTME implementation; this is a particularly sensitive issue in the
single-surgeon setting, because operative times
may be longer and the approach is more challenging [11].
Specific Challenges to a Single
Surgeon
Advocating for a Single-Team taTME Program
It can be quite difcult for a single colorectal surgeon to advocate an ambitious program that
requires an important amount of resources, such
as a signicant nancial investment by the institution as well as a large quantity of human
resources dedicated to this operation.
Firstly, a proposal delineating the advantages
of the single-team taTME operation using current
data from the institution could be created to demonstrate the potential benets for patients as well
as institutional progress and the intangible value
added by innovation. The proposal should consider the training of the surgeon, the volume of
minimally invasive rectal cases at the institution,
the potential for growth, and the need for continuous support for a sustainable program (equipment maintenance, slow and yet progressive
learning curve, specialized assistants, alignment
with goals of administration, and hospital leadership). The audience of the proposal should be
considered and may include surgical colleagues
and nursing staff, hospital administration, hospital leadership, and community agencies. Once a
proposal has been created, sources of funding
will vary depending on the characteristics of the
health-care system.
Securing Sustainable Funding
The initial implementation of a single-team
taTME program requires an investment in education and training, purchase of specialized equip-
ment, and utilization of facility resources– such
as longer initial operative time, additional nursing and surgical scrubs for the taTME setup, and
hospital resources in the case of complications
associated with implementation of a novel procedure. While the training of a single surgeon may
be easier than coordinating the schedule of two
high-volume surgeons to train for a procedure,
advocating for funding of a single-team TaTME
program is certainly more difcult for the single
surgeon.
The balance between cost, safety, and effectiveness is a fundamental consideration for successful adoption of any new procedure [18]. The
frequent lack of supportive evidence for new
techniques leads to making decisions mainly
based on qualitative information [19]. The introduction of new technology is frequently oriented
toward enhancing existing approaches, either by
minimizing the invasiveness of procedures,
improving clinical outcomes, optimizing cost, or
expanding the number of treated patients [20].
The initial cost of a taTME program should
consider carefully the decision regarding the
selection of the transanal platform. This has a different impact in the short term than it does on the
long term and is largely dependent on economies
of scale, as the different existing options carry different economic burdens. There are two different
types of platforms, either disposable, single- use
ones (based on the TAMIS technique) or reusable,
multi-use ones (based on the technique of TEM).
The latter, so-called “rigid” platforms are manufactured by either Richard Wolf™ or Karl Storz™.
Their technology incorporates an insufating system that is built-in to the apparatus. The initial
capital cost can be offset in time depending on the
volume of procedures performed.
There are now a variety of TAMIS-based platforms available through various vendors; of
these, the GelPOINT Path Transanal Access
Platform (Applied Medical™, Rancho Santa
Margarita, California) is perhaps most frequently
used for taTME (where available) since it was
specically designed for transanal access and is
thus quite versatile and, in the short-term,
relatively affordable. However, this latter is best
used in combination with a separate and quite
232
A. Caycedo-Marulanda et al.
costly insufation system (AirSeal® Conmed,
Utica, NY, USA). Thus with TAMIS-based
taTME, whether a single- or two-team approach
is used, such a system is considered integral to
the modern taTME since it stabilizes insufation
in a reduced space. Recently, however, an alternative to that has emerged which is a new stabilizing insufation bag, which is discussed
elsewhere.
Our experience has been entirely with the
TAMIS-based, GelPOINT Path Platform (aka
TAMIS platform); initially we introduced it to
perform TAMIS for local excision as a segue to
taTME [21]. This greatly facilitated the transition
to taTME, especially when approaching hospital
administrators to fund the new program, as the
value of advanced transanal surgery was already
appreciated.
The importance of teamwork cannot be overemphasized. Single-team taTME mandates cooperation though all OR channels. This includes
physician leadership, anesthesiologists, nursing
and surgical scrubs, intensive care providers, as
well as hospital administration. A cost-impact
analysis for the institution should be conducted
and should include a realistic understanding of
case complexity and operative time and, as best
as possible, quantify these values into an appropriate health-care economic model. All of the
above contributed toward helping hospital administration identify the nancial benets of minimally invasive rectal surgery (reduced length of
stay, early mobilization, decreased wound complication, and decreased hernia rates) improving
nancial sustainability of our taTME program
[22]. If long-term oncologic outcomes are someday proven with the taTME technique (versus
other minimally invasive approaches), then it will
ultimately drive both surgeons and institutions
toward a permanent adoption.
procedure. The discussion must include not only
the perceived benets of the procedure but also
the potential risk specic to taTME, such as urethral injury [24]. In addition, the possible alternatives to the procedure are worth including. Ample
time should be allotted to the consent process as
the patient’s understanding is crucial. Consent
must include discussing the prociency of the
operator and the specic innovative technique of
the taTME which has the objective of improving
resection quality and thereby patient outcomes. It
is relevant to discuss the single-surgeon presence
and its implications, including how the procedure
is performed in a sequential fashion rather than
synchronously. All this will denitively help to
make the consent as informative as possible [23].
Potential Complications
Complications specic to taTME include injury
to the urethra, the pelvic nerves, and the iliac vessels [24–26]. These potential complications are
not exclusive of a single-surgeon setting; however it is possible that they may occur more easily
in this type of scenario [11].
The planes of taTME are different than those
from a transabdominal approach, and it is much
easier to dissect in the wrong plane from a transanal approach [27]. This is due to the improved
visualization and superior retraction of the mesorectum allowing multiple planes to appear avascular and amenable to safe dissection. This is
particularly risky in a single-team approach;
therefore the single surgeon needs to constantly
reassess his or her own work and identify when
he or she is in the wrong plane.
Training
Patient Consent
Patient consent should be transparent and intentional [23]. The explanation of the taTME should
be clear and concise, and it is of great importance
to clarify that it is a novel approach to an existing
Excellent training courses exist to introduce a surgeon to the taTME technique. The major benet
of these programs is the opportunity to learn the
fundamentals of this complex operation and gain
cadaveric-based, hands-on experience. Recent
publications have focused on the inadequacy of a
single, 1- or 2-day training course in providing
22 Single-Team taTME
233
surgeons with the skill set necessary to safely
implement taTME [28]. Despite completion of a
didactic component, live case demonstration, and
cadaver-based training, mentoring and proctoring
are crucial to successful implementation of a
taTME program [13, 29]. All of the abovementioned elements are mainly focused on patient
safety [30]. The learning curve of different procedures is variable [31], and for taTME it has been
estimated to be around 40 procedures [32].
In a single-surgeon model, identifying a mentor/proctor in the early phases of the process is
particularly relevant; this relationship should be
maintained as long as necessary in order to
achieve prociency. This will allow the novice
taTME surgeon to gain condence and expertise
with more complex cases as the experience grows.
Identication of an appropriate mentor is discussed in existing training pathways [12, 33]. In
addition a number of other aids, including electronic tools, such as the D-Live® platform and the
iLapp educational app, are easily available to anyone interested in adopting taTME [34].
Required Personnel
A standard single-surgeon taTME team is comprised of six members: a colorectal surgeon, a
surgical assistant, an anesthesiologist, two scrub
nurses, and a circulating nurse. Germane details
regarding personnel for single-surgeon taTME
are discussed in the following sections.
Surgeon
It is strongly recommended that the surgeon be a
high-volume, experienced rectal cancer surgeon
who has completed colorectal fellowship training
[15]. She or he must also be comfortable with
platform-based transanal endoscopic surgery
using either TAMIS (transanal minimally invasive surgery) or TEMS (transanal endoscopic
microsurgery) prior to embarking on a taTME
program.
Training to achieve prociency is a long process. It requires the completion of structured
training courses as well as integration into a
taTME proctorship model. Training and acquisition of skill has been discussed. The surgeon
must be determined, patient, and willing to accept
that initial implementation may be frustrating
and difcult. In a single-team approach, the surgeon must be able to deal with challenging situations independently but also have the insight and
wisdom to convert to a conventional approach or
ask for help from a colleague when necessary. It
should be understood that the level of difculty
of an already quite complex operation is substantially increased when it is performed via the
single- surgeon approach.
Specialized Assistant
A procient surgical assistant is a key element of
the team, since her/his ability to provide traction
and countertraction facilitates exposure, therefore enhancing plane recognition by the surgeon.
This is imperative in the single-surgeon setting,
for instance, at the rendezvous and then during
the whole process of circumferential detachment
[35] (Fig. 22.1). In this sense, the specialized
assistant functions as a skilled rst assistant in a
manner similar to a resident in surgical training.
Not having an experienced assistant in a
single- surgeon taTME operation will undoubtedly have an impact on the performance of the
procedure, and the authors do not recommend
single-team taTME without a skilled assistant.
The role of the assistant is thus not limited to
driving the camera; therefore in order to assist in
a meaningful manner, it is very important that he
or she has a clear understanding of all the anatomy relevant to the operation and has considerable assist experience in advanced laparoscopy
[9, 10].
Dedicated Nursing Team
A knowledgeable resource nurse is important to
the success of the single-team. He or she must be
cognizant of the case sequence at all times and be
able to troubleshoot equipment as needed with or
234
Fig. 22.1 Assistant
on top
Fig. 22.2 Nurse setting up
A. Caycedo-Marulanda et al.
without the aid of a product specialist. Due to the
many intricate steps and details of the procedure,
it is necessary to have at least one dedicated nurse
who can choreograph all the necessary moves
within the theater and anticipate every potential
pitfall to facilitate seamless procedural operation.
We consider it is fundamental to have three
nurses available at each taTME case. A minimum of two circulating nurses should be present
for the entire duration of the procedure. One of
these nurses serves as a dedicated taTME nurse,
who invariably scrubs in during the transanal
portion of the operation, she/he should be
responsible for orchestrating the surgical equipment and instrumentation, and this individual
serves an assist to the primary surgeon by driving the camera during the dissection during
taTME (Figs.22.2 and 22.3).
22 Single-Team taTME
235
Fig. 22.3 Nurse holding camera Fig. 22.4 Extreme position
Equipment
novice assistant. This is because gravity alone
keeps the otherwise view- obstructing loops of
The type of equipment used in a single-surgeon
setting is not different than what is used during
dual-team approach. There is a need to have two
laparoscopic towers, one for the top and one for
the bottom. The generalities regarding the equipment for taTME have been previously discussed
in this textbook; therefore we will limit our discussion to a few specics that are essential for the
single-surgeon approach.
It is important to have a system device that
keeps the patient secured to the operating table
preventing him/her from sliding down or falling
off the table during the procedure while on
extreme positions, such as steep Trendelenburg
and/or lateral tilt (Fig.22.4). There is no xed rec-
small bowel free from the pelvis during abdominal and transanal dissection.
In our experience a regular insufator at the
top is sufcient. We have implemented the
Synergy® LEXION insufation ports, which
eliminate the issues that were initially encountered with smoke during deep dissection in the
pelvis. For the transanal dissection, it is crucial to
prevent billowing which is common with the use
of regular insufators; we have found it useful to
incorporate the AirSeal® IFS which can dramatically improve the operative clarity of the transanal approach by delivering a stable surgical
space and allowing continuous visualization of
the eld.
ommendation regarding what specic system
should be used. At our institution, we use the Pink
Pad (Pigazzi Patient Positioning System™) for its
Equipment Setup for a Single Team
safety, versatility, and ease of use. For a single
surgeon, this device allows steep Trendelenburg
position facilitating pelvic dissection, even with a
As discussed previously, the setup of equipment
for a taTME is a complex process that requires
236
A. Caycedo-Marulanda et al.
very specic planning and experience. Due to the
complexity of devices and the large footprint of
instruments and equipment, setup is critical to the
success of the procedure. Setup for a singlesurgeon taTME is no different in that it requires
knowledge of the steps of the procedure and an
understanding of the special limitations that the
surgeon may experience throughout the operation. It is critical for a single surgeon to ensure
that the team members know the operative plan
and are able to set up according to a preoperative
oor plan.
The setup for a single-team taTME can be
divided into the transabdominal equipment and
transanal equipment:
Transabdominal:
– Laparoscopic tower with air supply for
insufation
– Additional laparoscopic monitor
– Cautery and energy device sources
– Suction
– Equipment tray table with scrub nurse
Transanal:
– Laparoscopic tower with air supply for insuf-
ation (may require separate freestanding
machine)
– Cautery and energy device sources
– Suction
– Equipment tray with scrub nurse
As a single surgeon, the length of time of the
surgery must also be factored into the operative
plan and minimized when possible, and therefore
we set up in stages in order to allow for initiation
of the procedure. The specimen is then extracted
either through a Pfannenstiel incision or transanally. Pfannenstiel incision extraction of the
TME specimen holds the advantage of limiting
shearing and mesenteric disruption and the
potential for seeding of tumor cells.
The patient’s abdomen and perineum are then
prepped extensively. It is important to prep the
perineum rst so that any splashing of contaminant up toward the abdomen will be cleaned with
the abdominal prep. We use an alcohol-free solution for the perineum and chlorhexidine for the
abdomen.
Familiarity with equipment setup is essential
to the taTME procedure and can vary largely
depending on the layout of the operating theater.
We suggest two equipment setup formats, among
many conformations that exist, as these setups
have worked well at our respective institutions.
The specic position of laparoscopic equipment
and monitors can be modied to t the available
infrastructure of the institution (Fig.22.5. HSN
taTME room setup).
Setup 1: The transabdominal laparoscopic
tower is set up by the patient’s right shoulder with
cords draped over the right shoulder. The surgical
team (both assistant and primary surgeon) stand
on the patient’s right side, and the abdominal dissection is performed from here. The monitor for
the abdominal surgeon is placed across the operating table just beyond the patient’s left hip. The
abdominal surgical instruments and scrub nurse
are also across the operating table on the patient’s
left side.
The transanal component is set up with the
second laparoscopic tower beside the patient’s
right leg with cords and insufation tubing
draped along the right leg. The insufation tubing is draped across the pubic symphysis, while
the transanal suction, cautery, and instruments
are laid on a Mayo stand that rests across the
surgical eld similar to a typical perineal setup.
This tower typically consists of two monitors,
one with the abdominal laparoscopic view and
one for the transanal view. The monitors rest on
top of the transanal laparoscopic tower beside
the patient’s right leg to enable the transanal
surgeon to visualize both perspectives while
performing the taTME dissection. This also
allows the transanal surgeon to monitor the
assistant’s movements and ensure appropriate
traction.
Setup 2: The transabdominal laparoscopic
tower is set up by the patient’s right leg with the
monitor positioned directly between the
patient’s legs. The light and camera cords to this
tower should be positioned over the patient’s
right leg. The additional laparoscopic monitor is
positioned above the patient’s left shoulder. The
cautery, energy device source, and suction canister are placed over the patient’s right shoulder.
22 Single-Team taTME
Fig. 22.5 Room setup
237
The instrument table and scrub nurse should be
positioned on the patient’s left side. With this
initial setup, the transabdominal component of
the operation can begin.
The transanal component setup consists the
second laparoscopic tower setup above the
patient’s right shoulder and in front of the energy
source of the abdominal component. The monitor
for this tower is positioned directly in the midline
over the patient’s head. The light and camera
cords to this tower should be placed along the
patient’s right side going down to the transanal
eld. The cautery and energy source for the transanal component should be positioned by the
patient’s left leg. If there is an additional freestanding insufator, it too should be positioned
by the patient’s left leg. The instrument tray and
scrub nurse for the transanal component should
be positioned on the patient’s left side adjacent to
the left leg.
As a single surgeon, it is imperative that the
nursing team understands the setup such that the
setup for the second component of the operation
can occur while the rst component is
underway.
The Procedure
Where to Start
It is recommended to start the operation from the
abdomen. Valid rationale for this includes the
ability to survey the abdominopelvic cavity so as
to exclude carcinomatosis or other unforeseen
ndings which would otherwise preclude radical
resection. Another reason this “top-rst”
approach is preferred by experts especially for
single-team taTME is to familiarize the rst
assistant with the anatomy and countertraction to
enable transanal dissection when the single surgeon goes to the bottom to complete the taTME
dissection.
Transabdominal Approach
The operation is initiated laparoscopically with
the surgeon on the patient’s right side and the
assistant on the patient’s left side. Once access is
obtained via a Hasson entry at the umbilicus, 3
additional 5 mm ports are inserted (Fig. 22.6).
238
Port placement
Fig. 22.6 Port
placement
A. Caycedo-Marulanda et al.
The patient is then positioned in Trendelenburg.
The order of steps for the single-surgeon approach
has been previously described [36]. The transabdominal portion is not different than any laparoscopic dissection conducted for a low anterior
resection; our preferred technique includes the
following recommendations:
• Medial to lateral mobilization of the sigmoid
and descending colon with careful identica-
tion and protection of left ureter
• Medial to lateral mobilization of the splenic
exure, careful identication, and protection
of the pancreas
• Ligation of the inferior mesenteric vein, close
to the inferior edge of the pancreas
• Lateral mobilization of the left colon, including
the lateral attachments of the splenic exure
• Identifying and maturation of posterior rectal
plan
• Ligation of the inferior mesenteric artery,
proximal to the takeoff of the left colic artery,
either using clips or an energy device, approx-
imately 1 centimeter distal to the origin at the
aorta
• Transection of the mesentery of the proximal
margin from the ligated pedicle to the level of
the colon
• Systemic delivery of indocyanine green (ICG)
5ml to verify point of transection via uores-
cence angiography
• Circumferential TME dissection until the
level of the anterior peritoneal reection
• Opening of anterior peritoneal reection
During the transabdominal approach, while
the team is working toward the pelvis, the assistant is at the patient’s left side facing the monitor
stationed on the patient’s left side. At the next
point in the procedure, the patient is positioned in
reverse Trendelenburg with the left side up. The
assistant moves to between the patient’s legs, and
the surgeon remains on the patient’s right side but
is now working via the left shoulder monitor for
improved ergonomics. At this stage, the surgeon
will employ steps to take down the splenic exure to obtain adequate colonic length for the conduit. This completes the transabdominal
component and the team then moves to the transanal component of the surgery.
Transanal Approach
Once the transanal component is initiated, the
patient is again positioned in Trendelenburg
and the abdominal pressured is decreased. The
assistant is then positioned between the
patient’s leg on the right side and the surgeon is
seated centrally between the patient’s legs. In
this position, the surgeon then employs the following steps:
22 Single-Team taTME
239
• Placement of the transanal platform including
air insufation setup
• Placement of purse string to close the rectum
below the lesion
• Washout of the distal rectal stump
• Rectotomy circumferentially into the TME
plane
• Transanal TME until circumferential communication with abdominal component
• Continued dissection of TME until it is either
complete or it becomes excessively challenging in which case convert back to transabdominal component to complete nal TME
attachments
A bilateral pudendal nerve block using local
anesthetic is performed. This helps relax the anal
sphincter for effacement of the anus, facilitating
introduction of the TAMIS access channel. The
Lone Star® Retractor (Cooper Surgical) can be
used in combination with the TAMIS platform.
Alternatively, particularly with obese patients,
the anal canal can be effaced by placing temporary interrupted 2-0 sutures in the four quadrants
which encompass the top of the anal sphincter,
the anal verge, and the perineal skin. These steps
facilitate the introduction of the transanal
platform.
Once the platform is introduced, it can be
secured with silk stitches or in some cases with
the stays of the Lone Star Retractor. Once it is
secured, the subsequent step is to place the purse
string, and this is then followed by cleansing with
povidone and washing abundantly with sterile
water.
Circumferential incision of the rectum is per-
formed, until full division is achieved.
In the single-surgeon setting, it is important to
be prepared to revert to the transabdominal
approach in order to complete the circumferential
detachment. Eventually, the surgeon will then
return to the transanal component in order to
complete the anastomosis and may need to subsequently go back to the transabdominal component to conrm colonic orientation and create a
diverting loop ileostomy if indicated.
Systematic Approach to SingleSurgeon taTME
The operation is conducted sequentially using a
regular laparoscopic technique; the steps have
been previously reported [35] and are summarized below:
1. Positioning (proper padding and security
strap for steep Trendelenburg to facilitate
pelvic dissection without the help of a second surgeon)
2. Adjunctive monitoring (Foley catheter, arterial line, bilateral IV access) and ERAS
protocol
3. Single-surgeon abdominal component
(transabdominal laparoscopic dissection to
level of peritoneal reection)
4. Recognition of transition point (below peritoneal reection, prior to acute angulation of
rectum)
5. Single-surgeon perineal component (perineal retractor to efface anus, insertion of
platform, identication, and purse string of
distal margin)
6. Sterilization of perineal eld (generous
washout with antibacterial agent)
7. Recognition of full-thickness proctotomy
8. Constant reassessment for the identication
of “safe” anterior and posterior planes
9. Recognition and preservation of critical neurovascular structures
10. Rendezvous transition point (abdominal
retraction by surgical assistant) to facilitate
circumferential dissection
11. Meticulous hemostasis and extraction plan
(transanal vs transabdominal)
12. Reconstruction
When to Transition to the Bottom
As opposed to the two-team approach, in which
the team can be conducting the transabdominal
TME dissection simultaneous with the team conducting the taTME, the single-team approach can
240
A. Caycedo-Marulanda et al.
only conduct one dissection at a time. This makes
the decision to switch between the two approaches
more crucial and strategic as it can affect the efciency of the operation.
As previously described, the transabdominal
approach is conducted rst, and the upper TME is
dissected prior to moving to the transanal
approach. It is important to employ a “take what
is easy” philosophy as a single surgeon.
Therefore, from the top-down approach, the dissection is continued until it becomes challenging
as the pelvis narrows; at a minimum the single
surgeon should reach the anterior peritoneal
reection. Once the decision is made to go to the
bottom, it is important to remember to decrease
the peritoneal insufation pressure in order to
facilitate dissection and avoid billowing.
Roles and Assignments of the Dedicated Nurse and Surgical Assistant
During the transanal approach, the assistant is
standing on the patient’s right side, to the left of
the seated surgeon, remaining at the top and preparing to exert traction and countertraction as
required by the surgeon, with a scrub nurse at the
top, holding the camera temporarily. Our prefer-
ence is to have our dedicated taTME nurse to scrub
for the transanal part and hold the camera. The
assistant will stand on the left side of the surgeon;
the use of a exible-tip camera lens prevents any
interference with the surgeon’s hands. The camera
holder should be familiar with the taTME procedure, the capabilities of the camera, and the specic views that facilitate dissection within a
narrow eld (Figs.22.3, 22.4, 22.5, and 22.6).
ever, it strictly depends on the assistant’s ability
to generate adequate traction and countertraction,
hence the importance of having an experienced
and knowledgeable surgical assistant who can
interpret the anatomy as well as the surgeon’s
need for exposure.
Just prior to peritoneal entry, the assistant may
pull the specimen upward– this facilitates visualization of the planes while the surgeon synchronously pushes the specimen from below. It is
important to realize, as the surgeon conducts the
“bottom-up” portion of the taTME operation, it
may become more difcult than the two-team
taTME approach; this is the time when the assistant’s role is crucial by pulling the rectum up and
out of the pelvis as the dissection is done
transanally.
Once communication between the two spaces
has been established, the assistant will help by
providing countertraction as needed. Retraction
can be limited if the surgical assistant is not
familiar with laparoscopic tissue handling as
excessive or decient force can compromise the
integrity of the TME dissection. The point of rendezvous is variable and depends on the location
of the lesion as well as how much dissection from
above has been performed. If the operation starts
transanally, then the role of the assistant is much
more limited.
The assistant remains at the top providing
retraction. By looking at both screens (transanal
and transabdominal), the primary surgeon utilize
the additional vantage point provided by the dual
vantage point provided by the laparoscopic video
display. This can signicantly help with the intraoperative decision-making. In addition, the assistant should ensure the bowel stays properly
oriented and not twisted for the transanal extraction or the reconstruction.
Rendezvous: Meeting of the Planes
The rendezvous time and the circumferential dissection are slightly different for the singlesurgeon approach. In a two-team setting, both
surgeons are dissecting in synchrony, providing
retraction and exposure to one another. In the
single-surgeon scenario, it is possible to replicate
these retraction and exposure components; how-
Top-to-Bottom Transfers
A caveat for the single-team approach is the need
to alternate between top and bottom at least once
and more typically twice during the operation;
this means having to change gowns and gloves at
those times, but this can still be done efciently
by a team that has planned accordingly.