Surgical Staplers

What each device looks like, what it does, which cartridge to ask for, and how to avoid the errors that cause leaks.

Staplers are the instruments most registrars use confidently and understand least. This page covers the mechanics, the device types, the cartridge systems from both major manufacturers, and the handling errors that cause staple line failure.

Last reviewed: October 2026. Cartridge colours and staple heights are manufacturer-specific and change between product generations. Always read the actual cartridge packaging. Nothing here replaces that.

---

PART ONE - HOW A STAPLE WORKS

1. B-formation

Surgical staples are not crimped flat. They are driven through the tissue against an anvil with shaped pockets, which curls each leg back on itself into a B shape.

The B shape matters because it approximates without crushing. The loop of the B holds tissue securely while leaving a space through which submucosal blood vessels continue to perfuse. A staple that closes flat strangulates the tissue in the staple line and causes necrosis, which is one route to an anastomotic leak.

2. Open and closed staple height

Two numbers describe every cartridge, and the manufacturers quote them differently. This is the commonest source of confusion.

• Open staple height - the height of the uncrimped staple as loaded
• Closed staple height - the gap between the staple crown and the formed legs after firing, which is the space the tissue actually occupies

Medtronic generally quote open height. Ethicon generally quote closed height. An Ethicon blue reload at "1.5 mm" and a Medtronic blue at "3.5 mm" are not wildly different devices. They are roughly comparable cartridges described by different measurements.

What this means on the list: never compare cartridges across manufacturers by the number alone. Compare by colour within a system, and by the tissue descriptor across systems.

3. Choosing by tissue thickness

Thin tissue in a tall staple leaves gaps. Thick tissue in a short staple is crushed and the staples tear through. Neither error is safe, but under-sizing on thick tissue is the more dangerous of the two because the damage is done at the moment of firing and cannot be undone.

4. Graduated versus uniform staple height

Medtronic's Tri-Staple cartridges place three different staple heights in the rows on each side of the cut line, with the shortest innermost (nearest the cut) and the tallest outermost.

The rationale is that the cut edge needs the tightest compression for haemostasis, while the outer rows can be looser to allow fluid to escape and reduce the stress that tears staples out of thick tissue. Ethicon's equivalent concept is Gripping Surface Technology, which textures the cartridge face to stop tissue sliding out of the jaws during closure rather than varying staple height.

---

PART TWO - THE DEVICES

5. Linear cutter: GIA, TLC

GIA stands for gastrointestinal anastomosis (Medtronic/Covidien). TLC is the tissue linear cutter (Ethicon). They are the same class of device from different manufacturers, and people use the names interchangeably regardless of which is on the trolley.

The device places two double rows of staples and runs a knife between them, so both sides of the division are sealed. This is the workhorse for open bowel work.

Typical uses: dividing small or large bowel, creating a side-to-side (functional end-to-end) anastomosis, dividing a thick mesentery or a gastric pedicle.

6. Linear non-cutting: TA

TA stands for thoracoabdominal. It places two staggered rows and does not cut. If you want to divide, you cut along the stapler jaw with a scalpel before releasing.

Typical uses: closing a rectal stump in a Hartmann's procedure, closing a gastrotomy or enterotomy, securing a bronchial or lung stump, closing the common enterotomy of a stapled anastomosis.

Sizes: 30, 45, 60, 90 mm.

7. Endoscopic linear cutter: Endo GIA, Echelon

The handle is reusable within the case and takes multiple reloads. Articulation lets you angle the jaws to meet tissue squarely, which matters enormously in the pelvis where a straight-on approach to the rectum is impossible through a standard port.

Typical uses: laparoscopic bowel division and anastomosis, appendix base and mesoappendix, rectal division in anterior resection, sleeve gastrectomy, lung wedge resection, splenic hilum.

8. Circular stapler: EEA, CDH

EEA stands for end-to-end anastomosis (Medtronic). CDH is Ethicon's circular device. The anvil detaches, is placed in the proximal bowel and secured with a purse-string, then reconnected to the central shaft before firing.

Typical uses: colorectal anastomosis after anterior resection, oesophagojejunostomy after total gastrectomy, gastrojejunostomy in bypass surgery.

Sizing: choose the largest diameter the bowel will accept without tearing. 25 mm is commonly used for a low rectal anastomosis, 28/29 mm for most colorectal work. Too small a device risks anastomotic stricture; forcing too large a device tears the bowel wall.

Two things that are not optional

Inspect the doughnuts. After firing, two complete rings of tissue should come away with the device. An incomplete doughnut means the staple line is incomplete at that point. Document that you checked them.

Leak test the anastomosis. Fill the pelvis with saline, occlude the bowel proximally and insufflate air per rectum. Bubbles mean a defect that must be found and repaired. A positive leak test is a reason to reinforce, or to defunction.

9. Other devices

---

PART THREE - CARTRIDGES

Colours mean different things in different systems. Learn the system your unit stocks, and read the cartridge every time.

10. Medtronic Tri-Staple 2.0

Each cartridge has three graduated staple heights on each side of the cut line.

Reload lengths 30, 45 and 60 mm. Purple passes a 12 mm port; black needs a 15 mm port, which is worth knowing before you have placed your ports.

Older Medtronic universal reloads use single staple heights: white/grey 2.0 mm vascular, blue 3.5 mm, gold 3.8 mm, green 4.8 mm. Both generations may be on the shelf.

11. Ethicon Echelon

Ethicon quote closed staple height as the primary figure.

Reload lengths 45 and 60 mm, six staple rows.

12. The colour trap

Medtronic Tri-Staple has no blue cartridge. If your unit stocks Tri-Staple and you ask for "a blue one," the scrub nurse will either hand you an older universal reload or ask you what you mean. Both waste time. Learn the system in front of you.

13. Which cartridge, by tissue

This is a starting point, not a rule. Tissue thickness varies with inflammation, oedema, steroids, previous radiotherapy and body habitus. Assess the tissue in front of you, and ask your consultant what they use.

---

PART FOUR - TECHNIQUE AND FAILURE

14. The sequence

1. Choose the cartridge by feeling the tissue, not by habit.
2. Clear the application site. Fat, vessels, clips, adjacent bowel and previous staple lines all interfere with staple formation. Firing across a metal clip can jam the device or deform the staples.
3. Position both jaws under direct vision. Confirm nothing unintended is between them, particularly the back wall.
4. Close the jaws and wait. Allow at least 15 seconds, and longer for thick tissue. This lets interstitial fluid displace so the tissue reaches its compressed thickness before the staples form. Firing immediately is one of the commonest causes of poor staple formation.
5. Fire smoothly at a steady rate. Jerking the handle produces uneven staple lines.
6. Wait again before releasing, then open the jaws gently. Pulling a closed stapler off tissue tears the staple line.
7. Inspect the line for bleeding and integrity.

15. Why staple lines fail

The principle worth carrying: most anastomotic leaks are not caused by the staples. They are caused by tension and poor blood supply. A stapler cannot rescue a badly mobilised or poorly perfused anastomosis, and no cartridge choice compensates for either.

16. Reinforcement and the buttress question

Staple line reinforcement (preloaded buttress, or applied strips) is used in some bariatric and thoracic practice to reduce bleeding and air leak. Evidence of benefit is strongest in lung resection for prolonged air leak. In colorectal surgery it is not standard, and routine use is not supported.

Oversewing a staple line is similarly variable practice. It is commonly done for a duodenal stump, less commonly elsewhere, and is a matter of unit and surgeon preference rather than established evidence.

17. If the stapler fails to fire

A jammed stapler with the jaws clamped on bowel is a genuinely uncomfortable moment. The sequence that helps:

1. Do not force it. Forcing a jammed knife can tear the tissue held in the jaws.
2. Say out loud that the device has not fired, so the scrub team can open a second device.
3. Most devices have a manual release. Know where it is on the device you are holding, before you need it.
4. If the jaws cannot be released without tearing, the tissue within them will need to be divided and oversewn or resected. Call for senior help early rather than improvising.
5. Keep the failed device. It goes to clinical governance, and it is reportable to the MHRA through the Yellow Card scheme.

---

QUICK REFERENCE

---

Before You Scrub

Three questions that save time and avoid error, and that nobody will think less of you for asking:

1. "Which stapler system do we stock here?" Medtronic and Ethicon colour systems do not map onto each other.
2. "Which cartridge do you use for this step?" Preferences vary legitimately between consultants.
3. "Where is the manual release on this device?" Ask before you need it, not during.

---

Educational resource for surgical trainees. Cartridge colours, staple heights and port requirements are manufacturer-specific and change between product generations. The figures here reflect current Medtronic Tri-Staple 2.0 and Ethicon Echelon specifications at the date of review, but the cartridge packaging and the instructions for use are the authoritative source in every case. Not a substitute for supervised training or clinical judgement.