The Next Era in GI Surgery BioDynamixTM
AnastomosisThe Colon Ring
Clinical Training Team
HISTORY OFCompression Anastomosis
Routine Anastomotic Techniques—Handsewn vs. Staples
• Until recently, there were only two routinely used techniques
• No difference whether sewn in one or two layers
• Stapling is faster
• Surgeon preference prevailed
• Literature supports whichever the surgeon uses
3
“Eminence-”…(Instead of Evidence-)…Based Medicine
• “Repeating the same mistakes with increasing
confidence over an impressive number of years.”
O'Donnell M. A sceptic's medical dictionary. London: BMJ Books, 1997.
Results in—
4
The Velocity of Change
• “The lag between the discovery of more efficacious forms of treatment and their incorporation into routine patient care is unnecessarily long, in the range of about 15 to 20 years.”
Institute of Medicine
Crossing the Quality Chasm 2001
When change occurs—
Change Is Hard
About Compression Anastomosis
• Compression anastomosis (CA) device is sutureless and staple-less – there are no punctures through viable colonic tissue.
• CA consistently compresses the blood vessels, creating an immediate and virtually complete hemostasis.
• CA device requires no foreign bodies (sutures, staples) to remain in the healing zone after 10-14 postoperative days.
• The result is full recovery of the natural multi-layer tissue structure and normal lumen size.
Compression Anastomosis Concept
• CA has long been an attractive goal…older than staplers!!!• Results in an exceptionally clean seal.• Controlled local ischemia leads to necrosis, triggering a natural
healing process.• Device is expelled from the body, resulting in a larger lumen than
with a stapled anastomosis.
• Historical Evolution of Compression Anastomosis (CA)• First developed by Denans in 1826• Earliest practical device, the “Murphy Button” dates to 1891• More recent products –
• Valtrac (BAR) - introduced in 1984• AKA-2 ring (Russia)
The Perfect Solution for GI Anastomosis
Murphy Button
1891
• Two circular metallic rings• Scalloped in the shape of a bowl• Double purse strings• Steel alloy coiled spring• Necrosis of compressed tissue• Very narrow lumen• Frequent extrusion• Limited clinical success• Stenosis/Stricture - early or late
Valtrac Biofragmentable Ring (BAR)
1984
Biofragmentable Anastomotic Ring
• Two rings (absorbable)• 87.5% polyglycolic acid• 12.5% barium sulfate
• No springs• Double purse string• Snapped shut (clamp)• Four sizes—25, 28, 31, 34
• 1.5-2.5 mm gap• ID size 11-20 mm
• Passed transanal in 2-3 wks
• Often incomplete absorption
• Decent results• Difficult to use
AKA-2
1989
• Three sizes• Plastic anvil ring w/metal screw• Transanal applier w/
• Double plastic rings• Multiple spikes
• 6 blunt pins• 18 fish-hook pins
• Coiled steel alloy springs• Double purse string• No consistent compression• Necrosis of incorporated tissue• Passed out with stool• Used primarily in Germany
ColonRingTM
Detachable Anvil Head Assembly
Trocar
Operating Knob
ColonRing™ Housing
Cutting Trigger
Cutting Handle
ColonRingTM
Applier
Locking Spring
Purse String Notch
Grasping Notch
Plastic Anvil Ring
Anvil Shaft
Nitinol’s Basic Properties
• The Colon Ring™ is manufactured with Nitinol, a biocompatible alloy of nickel and titanium with several unique properties –
– Shape Memory – Unlike steel, Nitinol fully recovers its shape when heated past a transition temperature.
– Superelasticity – Nitinol can be stretched far beyond the limits of other metal alloys (~20 times more than steel), while still remaining capable of returning to its original shape.
– Constancy of Force – When deformed 1% to 6% from its predefined shape, Nitinol applies a consistent force range as it returns to its original shape.
– (Relaxes in cold and contracts in heat.)
Leaf Work Zone
Nitinol Leaf Spring at 6% Deformation
Nitinol Leaf Spring at 1% Deformation
Steel Leaf Spring at 0.4% Deformation
Work Zone 6%-1%
Nitinol Leaf Spring at 0% Deformation
• When released on tissue, Nitinol leaf springs will follow the unloading plateau curve to compress the tissue.
Implementing Nitinol’s Unique Features
• When cooled & loaded, Nitinol leaf springs are deformed (Flattened).
Nitinol’s Constancy of Stress (Force)
How the ColonRingTM Works
Nitinol Spring Leaf at 6% Deformation
(Thick Tissue)
Nitinol Spring Leaf at 1% Deformation
(Necrosed Tissue)
Nitinol Spring Leaf at 3% Deformation
(Thin Tissue)
Variation of Tissue Thickness within the Colon RingTM
• Leafs within the same ring can tolerate different deformation levels while still exerting almost the same force around the entire ring.
Nitinol Spring Leaf at 6% Deformation (Thick Tissue)
Nitinol Spring Leaf at 3% Deformation (Thin Tissue)
Tissue Thickness
Tissue Thickness
Application of the Colon RingTM
• The gap between the two ring elements adjusts according to tissue thickness.
• With greater tissue thickness, a larger gap is obtained (up to maximum).
• The Nitinol springs adjust the initial gap by compressing the tissue with a predefined force.
• The Nitinol springs within the ring act along the unloading plateau path (6%-1% of Strain) where a nearly constant force acts on the tissue.
• The fact that a nearly constant force can be obtained gives the Colon RingTM the ability to control the compression process.
• As the compression process progresses, the tissue trapped between the rings necroses, while the new anastomosis forms externally, and the gap decreases until "zero" gap occurs.
• At "zero" gap the ring detaches and is expelled naturally by intestinal peristalsis.
Compression Anastomosis Concept
Compression Force
Spikes
Mechanical Force
Biological Force
• CA has long been an attractive goal…Results in exceptionally clean seal• Controlled local ischemia leads to necrosis, triggering natural healing process• Device is expelled from the body resulting in larger lumen
27 mm ExternalDiameter
18 mm InternalDiameter
Stapled anastomosis reduces lumen
diameter ~10mm
Lumen Size – ColonRingTM vs. Staplers
Ring Discharged
4.5-5.0 mm lip
Lumen Size -- Staplers
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Colon Ring™ Ease of Use
• Colon Ring™ placement device is similar to common circular staplers, minimizing the surgeon’s learning time.
• Compact anvil design allows for easy removal after ring is placed.
• No anvil head is dragged through a fresh anastomosis.
• The majority of surgeons rate it very easy to use.
Why Change?
Lawn Care Preference?
Landscape Preference?
Surgeon (and/or Patient) Preference? (at 3 Months)
EEA Stapler w/Strictured Anastomosis
ColonRingTM w/Almost Seamless Anastomosis
Surgeon Preference?
Tissue Structure at 3 Weeks
ColonRing™ Anastomosis Appearance
Postop 3 Months PO
Compression Anastomosis vs. Staplers
Compression Anastomosis Staplers
1. No puncture of viable bowel wall layers Staplers puncture the viable colonic wall – bleeding and exposure to bowel microbial flora
2. Ring is expelled from the body within 30 days Staples stay in the body for years
3. Anastomotic circumference healing is free of foreign body reaction Healing may be by foreign body reaction
4. Preservation of continuity of bowel wall layers
Staplers hinder the natural structure of the reconnected bowel wall – sustained trauma to the tissue
5. Recovery of the lumen in one month Lumen will lose 10-15% of its size
NiTi ColonRingTM Company Data
• Averages represent averages of all data received for a given data point
• Data collected from over 600 surgeons at 375 sites in North America, Europe and Asia
• Sites range from major university medical centers to community-based hospitals
• Patients were 56% female, 44% male• Procedures were 7% right hemicolectomy,
48% left hemicolectomy, 45% anterior resection
• Cases were 50% open and 50% lap• Average age – 62.4 (14 to 91)• Average BMI – 28.1 (16 to 55)• Over 8,000 cases performed worldwide• Of the 3,500 AR procedures, more than
450 involved chemo-radiated patients• In all 7,641 commercial cases covered in
this document, a clinical leak rate of 3.0% (228 cases) was reported.
404%
435
42%15615%
40239%
>25 cm<10 cm 11-15 cm 16-25 cm
Height of AnastomosisIn 1,033 Cases