The Foundation Tray of General Surgery
The laparotomy tray, sometimes called a major or basic laparotomy set, is the backbone instrument tray for open abdominal procedures ranging from exploratory laparotomy to bowel resection to open cholecystectomy. Knowing exactly what belongs on this tray, and why, is fundamental knowledge tested throughout the CST exam's instrumentation content, and it is knowledge you will use on nearly every open general surgery case in your career.
Cutting Instruments
A standard laparotomy tray includes multiple scalpel handles, typically a number 3 handle for a number 10 or 15 blade for skin incision and a number 4 handle for a number 20 or 22 blade for deeper tissue. Metzenbaum scissors, usually in a 7-inch length, handle delicate tissue dissection, while Mayo scissors, both straight and curved, are reserved for heavier tissue and suture cutting. Curved Mayo scissors should never be used interchangeably with Metzenbaum scissors even though they look similar, since the heavier blade of a Mayo scissor can crush delicate tissue.
Clamping and Hemostatic Instruments
Expect a generous supply of curved and straight Kelly and Crile hemostats for vessel clamping, along with longer Kocher clamps that have interlocking teeth for grasping tougher tissue like fascia. Right angle clamps are included for dissecting around structures such as the cystic duct or ureter. Babcock clamps, with their fenestrated, non-crushing jaws, are used to grasp bowel or other delicate tubular structures without causing tissue trauma, and Allis clamps with their toothed tips grasp fascia or skin edges during closure.
Retractors for Exposure
A laparotomy tray typically includes a self-retaining retractor system, such as a Balfour or Bookwalter, along with handheld retractors like Richardson retractors in multiple sizes, malleable ribbon retractors, and Deaver retractors for deep abdominal exposure. The surgical technologist should know each retractor's blade depth options and be ready to hand the correct size before being asked, since retractor exchanges mid-case slow the operation.
Grasping, Suturing, and Closing Instruments
Tissue forceps, both toothed and non-toothed Adson and DeBakey styles, allow atraumatic and traumatic tissue handling depending on the structure involved. Needle holders in multiple lengths accommodate suturing at different tissue depths, and the tray should include suture scissors dedicated solely to cutting suture material, never tissue. A complete tray also includes towel clamps for securing drapes and a full complement of sponges and lap pads that must be counted per AORN and AST surgical count protocols before the case begins.
- Multiple scalpel handles sized for skin and deep tissue incisions
- Metzenbaum and Mayo scissors, kept separate by function
- Kelly, Crile, Kocher, right angle, Babcock, and Allis clamps
- Self-retaining and handheld retractors including Richardson and Deaver
- Toothed and non-toothed tissue forceps, needle holders, and suture scissors
Tray Variations Across Facilities
While the core instruments described above appear on nearly every laparotomy tray, exact tray composition varies somewhat between facilities based on surgeon preference, case volume, and institutional tradition. Some facilities maintain a single comprehensive "major tray" used for all open general surgery cases, supplemented with procedure-specific additions pulled separately, while others maintain several distinct laparotomy tray variants, such as a smaller tray for limited procedures and a larger, more heavily instrumented tray for extensive resections. Learning your specific facility's tray composition by heart, rather than relying solely on a generic textbook list, is an early and important part of orienting to any new surgical technologist position.
It is also worth understanding that a laparotomy tray, however comprehensive, rarely stands alone during an actual case. Vascular clamps, bowel technique instruments, or a self-retaining retractor system beyond what the base tray includes are frequently pulled as supplemental items based on the specific procedure, and anticipating these additions before the case begins, based on the scheduled procedure and the surgeon's preference card discussed in our case management content, prevents mid-case delays waiting for sterile processing to send an additional tray.
Building Instrument Recall Through Functional Grouping
Rather than memorizing the laparotomy tray as an undifferentiated list, organizing your recall around functional groups, cutting instruments, clamping instruments, retractors, and closing instruments, mirrors how the tray is actually organized on the back table and how a surgeon will request items during an actual case. This functional grouping approach also transfers well to learning other specialty trays, since nearly every surgical tray follows this same underlying logic even when the specific instruments differ considerably between specialties.
New surgical technologists sometimes find it useful to physically practice setting up a mock laparotomy tray, whether during school lab time or informally during a quiet moment in clinical rotation, since the physical act of organizing instruments by hand builds a different, more durable kind of memory than reading a list alone. This kind of kinesthetic practice, paired with the written review discussed throughout this content, supports the instrument recognition speed that both real practice and the CST exam ultimately require.
Photographic and video-based study resources can further reinforce this functional grouping approach, since seeing an instrument in its actual physical context, being held and used during a real or simulated procedure, builds a stronger visual association than a static labeled photograph alone. Many candidates find that combining still image identification drills with video footage showing instruments in active use produces noticeably faster recognition speed than either resource type used in isolation, since the two formats reinforce different aspects of genuine instrument familiarity.
A Foundation Worth Mastering Early
Because the laparotomy tray underlies so much of general surgery, mastering it early in your training pays dividends across nearly every other specialty tray you will later learn, since many specialty trays simply add procedure-specific instruments to this same foundational core. Investing extra study time here specifically, rather than treating it as just one tray among many, reflects a genuinely efficient use of limited study time given how frequently this foundational knowledge resurfaces.
Instructors and preceptors frequently notice that students who have truly internalized this foundational tray progress more quickly through specialty rotations later in their training, since so much specialty-specific learning builds directly on top of this core instrument vocabulary rather than replacing it entirely.
Review the full family of clamps and forceps in more depth with our instrument identification cheat sheet, and pair this knowledge with proper counting procedure in our Intraoperative Patient Care domain guide. If instrument recall is your weak spot, check out our exam prep plans for image-based instrument drills.