Exam 1 Lec1-6 Flashcards
Who are the historic figures in the evolution of surgery?
- Aristotle
- Grandfather of Comparative anatomy
- First to describe the absence of gallbladder in horses
- Andreas Vesalius (1500s)
- Father of modern human anatomy
- Ambroise Pare (1500s)
- Innovative wound treatments
- Turpentine ointment more effective than boiling oil
- Controlling hemorrhage by ligation
- Gunshot and shrapnel (small pieces of metal in wound) wounds in horses
- John Lister (1800s)
- Pioneer of antiseptic surgery by Louis Pasteur concepts
- William T.G. Morton (1800s)
- Dentist
- First use of ether
- William Roentgen
- Discovered X-rays 1895
- 1896 first medical use of X-rays. Thomas Edison discovered the fluoroscope in 1896
- John Hunter (1700s)
- Anatomist and surgeon
- Began using the scientific approach to medicine and surgery
Give examples of major developments in surgery and the impact/outcomes for patients?
- Caesarian Section
- 272 BC first time performed
- Mother died of poisoning, but baby saved
- High mortality in live mothers
- Uterus closing improved survival
- Routine in VetMed, low mortality
- Surgical technique William Halsted
- Early 1900s
- Meticulous
- Hemostasis
- Local anesthetics
- Patient care
What are some recent advances and how do they impact modern surgical techniques?
- Research in shock, trauma, wound healing
- Perioperative care
- Structured residencies programs ACVS 1967
- Minimal invasive surgery
- Laparoscopically assisted gastropexy
What are the Instrument Categories?
- Scalpels
- Scissors
- Needle holders/Needle drivers
- Tissue forceps
- Hemostatic forceps
- Retractors
- Miscellaneous instruments
Scalpels
- *Slide cutting**
- *Blade should be perpendicular to the skin surface**
- Used to incise tissue
- Reusable No. 3 and 4 with detachable blades
- Available disposable blades/handles
- Some with Retractable blade shield
Blades
No. 10: small animal surgery common
No. 15: smaller version of 10, precise incisions in smaller tissue
No. 11: Stab incisions into fluid-filled spaces/organs
No. 12: Curved angle, limited applicability, cats elective dissection onychectomy (declawing)
Types of scalpel grips and uses
- Pencil grip: 30-40 degrees. Shorter, finer, more precise incision. Angle reduces cutting edge contact, best for long incisions.
- Fingertip grip: Best accuracy and stability for long incisions
- Palmed grip: Strongest hold, allows exertion of great pressure on the tissue, often unnecessary
Scissors
- Type of point
- Blade shape
- Cutting edge
Held with the tips of the thumb and ring finger. Index finger resting on the shanks near the fulcrum. Rings should be kept near the distal finger joint
- Curved: greater maneuverability and visibility
- Straight scissors: greatest mechanical advantage when cutting tough or thick tissue
- Metzenbaum (Metz, Nelson, delicate, or tissue scissors): more delicate than Mayo scissors. Sharp and blunt dissection or incision of finer tissues
- Mayo scissors: used for cutting dense, heavy tissue, such as fascia.
- Iris Scissors (curved or straight): delicate, ophthalmic procedures and other meticulous surgeries, fine cuts
- Bandage scissors: blunt tip to reduce risk of cutting skin.
Scissors Grips
The larger the angle between the blades when cutting, the less the scissors stabilize the tissue and the less accurate the cut is
Using the end of the blade stabilizes tissue more securely, and allows a more precise cut
- Wide-based Tripod Grip
- Most efficient hold
- Thumb and ring finger through the rings.
- Middle finger on top of ring finger
- Index finger along handles towards fulcrum.
- Backhand Grip
- Typically for cutting from left to right (less awkward)
- Thumb and middle finger through the rings
- Handle resting on 3rd and 4th fingers
Should the scissors be completely closed while making incision? Why?
How are scissors used during blunt dissection? What typed of tissue is to be avoided?
They should not be completely closed is the cut is to be continued because it causes a ragged incision.
They should be nearly closed, advanced, and nearly closed again.
-Blunt dissection: (e.g., separation of tissue by inserting the points and opening the handle) may be used to separate loosely bound tissues, such as muscle or fat, or to undermine skin edges
avoid tougher tissue or where precise cuts are possible.
Needle Holders
- Grasp and manipulate curved needles
- Long needle holders facilitate working in deep wounds
- *Grasp suture only at the suture’s end, where it will not be in a surgical knot!**
- Needle holder finely serrated or smooth jaws: for holding suture, prevent fraying or cutting suture.
- High-quality: noncorrosive, high-strength alloy, glare-free finish. Diamond surface tips or tungsten carbide (replaceable inserts)
- *Mayo-Hegar & Olsen-Hegar: ratchet lock just distal to the thumb. MEDIUM to COARSE needles
- *Castroviejo: spring and latch mechanism for locking
- *Mathieu: ratchet lock at the proximal end of the handles, which permits locking and unlocking simply by progressively squeezing the handles together.
Needles
- *Needles should be placed perpendicular to the needle holder. **
- Parts of needle: point, body/shaft, Swaged (eye) end.
Needle generally grasped near its center: advances through tissue with greatest force and less risk of breakage
Needle holders Grips
- Palmed grip: no fingers are placed in the rings, upper ring rests against the ball of the thumb. Strong driving force but less precision
- Thenar grip: the upper ring rests on the ball of the thumb and the ring finger is inserted through the lower ring. Good mobility, but handles pop apart when releasing, tissue movement.
- Thumb-ring finger grip: thumb is placed through the upper ring and the ring finger through the lower ring. Best precision and preferable for delicate tissue.
- Pencil grip: Used with Castroviejo needle holders.
Tissue Forceps
- Tweezer-like, non-locking instruments used to grasp tissue.
- Tissue forceps with large teeth should not be used to handle tissue that can be easily traumatized
- DeBakey forceps: smooth tips, for delicate tissue, such as viscera or blood vessels
- Brown-Adson forceps: have small serrations on the tips that minimize trauma but facilitate holding tissue securely.
Tissue Forceps
- Tweezer-like, non-locking instruments used to grasp, stabilize, expose tissue layers during suturing, etc.
- Tissue forceps with large teeth should not be used to handle tissue that can be easily traumatized
- DeBakey forceps: smooth tips, for delicate tissue, such as viscera or blood vessels
- Brown-Adson forceps: have small serrations on the tips that minimize trauma but facilitate holding tissue securely.
- Generally used in the non-dominant hand
- Should be held in the pencil position
- Holding the shanks in the palm greatly limits maneuverability.
- When not in use they can be palmed
- When needles are grasped with forceps during suturing, they should be grasp perpendicular to the shaft.
Hemostatic Forceps
- They are crushing instruments used to clamp blood vessels
- Straight or curved tips vary in size from 3 inches (Mosquito hemostats) to 9 inches (Angiotribes)
- Serration on the jaws of larger hemostat forceps may be transverse, longitudinal, diagonal, or a combination.
- Longitudinal serrations: gentler to tissue than cross-serrations.
- Serration extend from the tips of the jaws to the boxlocks
- Kelly forceps: transverse serrations extend only over the distal portion of the jaws. Used on larger vessels.
- Crile forceps: have transverse serrations that extend over the entire length of the jaw. Used on larger vessels.
- Rochester-Carmalt forceps: are larger crushing forceps often used to control large tissue bundles, such as during an ovariohysterectomy. They have horizontal grooves with cross-grooves at the tip ends to prevent tissue slippage.
- Satinsky forceps: Specialized cardiovascular forceps (e.g., Satinsky forceps) allow occlusion of only a portion of the vessel.
- Ochsner forceps: have large teeth at the tip, which help prevent tissue slippage within forceps.
- Allis Tissue Forceps: have interlocking sharp teeth; firmly grasps tissue that is going to be removed from the body.
- Babcock tissue forceps: have broad, flared, and blunt grasping tips that are more delicate and can be used carefully on tissue remaining in the body (stomach).
- Doyen intestinal forceps: non-crushing, occluding forceps with shallow longitudinal striations that are used to temporarily occlude the lumen of the bowel.
Retractors
- Hand-held retractors and self-retaining retractors are used to retract tissue and improve visualization.
- Ends maybe hooked, curved, spatula-shaped, or tooth.
- Some maybe bent by the surgeon to conform to the structure or area of the body being retracted.
- Hohmann: spatula-shaped
- Malleable or ribbon: maybe bent
- Senn (rake) retractors: small, double-ended retractors with three small, finger-like projections on the end and a flat, curved blade on the other
- Army-Navy: larger, blunt broad blades on each end for retraction of large amounts of tissue.
- Self-retaining retractors (e.g., Gelpi, Weitlaner) maintain tension on tissue and are held open with a boxlock or another device (e.g., a set-screw, such as in Balfour and Finochietto retractors).
- Balfour retractors: retract abdominal wall
- Finochietto: during thoracotomies.
Retractors
- Gelpi: self-retaining, maintains tension on tissue, held open by boxlock or another device.
- Weitlaner: similar to Gelpi, but with three theeth.
Miscellaneous Instruments
- Magnifying loupes: helpful in improving visibility of small tissues, etc.
- Specialized example: Arthrex Meniscal Knives
- Suction tips:
- Poole: not precise, sucking the pool
- Yankauer
- Frazier: very precise
Miscellaneous clamps and forceps
- Backhaus towel clamp:
- Allis tissue forceps:
- Babcock
Orthopedics
- Lempert, Ruskin, Kerrison
- Duck-bill double action rongeurs
- Bone holding forceps
Periosteal elevators
- AO-round edge
- AO-curved blade and straight edge
- Freer
Orthopedics
- Chisel
- Mallet
- Orthopedic wire
- Wire twisters
- *Jacobs chuck and key**
Neurosurgery
- Lens loop
- Small nerve root retractor
- Tartar scraper
- Freer dissector
- Large right angle nerve root retractor.
Suture Materials and Patterns
Suture function Size Characteristics Suture materials Suture selection: wound repair, hemostasis, healing supporting tissue layers. Depending on type of tissue and anticipated duration of healing. Needles Suture Patterns
How long does suture need to function according to the type of tissue?
- Muscles, subcutaneous tissue, skin: a few days of support needed
- Vessels: hours of ligature support until clot forms
- Fascia: weeks
- Tendons: months
Individual patient variation further affects suture choice
- Infection
- Obesity
- Malnutrition
- Neoplasia
- Drugs (e.g., steroids)
- Collagen disorders
- Hypoproteinemia
- Radiation therapy
What is the primary function of suture?
What are some ideal characteristics of suture?
Maintain apposition of tissue until wound’s tissue strength returns
- Easy to handle
- Reacts minimally in tissue
- Noncapillary
- Nonallergenic
- Noncarcinogenic
- Nonferromagnetic
- Absorbs with minimal reaction after the tissue has healed
- Holds securely when knotted
- Inhibits bacterial growth
- Resists shrinking in tissue
- *The ideal suture material does not exist**
- *surgeons must choose a suture that most closely approximates the ideal for a given procedure and tissue**
Suture Size, Flexibility.
USP: United States Pharmacopeia
- 12-0 being the smallest
- 7 being the largest
- Dimensions from fine to coarse
- Smallest diameter suture that will adequately secure wounded tissue should be selected: minimize trauma as it passes through tissue, reduce the amount of foreign material left in the wound.
- *There is no advantage in using suture that is stronger than the tissue**
Flexibility
- Torsional stiffness and diameter determines it
- Ligating vessels or performing continuous suture patterns
- Less flexible can not be used on small vessels
- Nylon and surgical gut are relatively stiff compared to silk suture.
- Braided polyester sutures have intermediate stiffness
Suture surface characteristics and coating
Which sutures have Capillarity and which don’t?
- It influences the ease with which it is pulled through tissue (amount of friction or “drag”) and the amount of trauma caused.
- Smooth surfaces suture: for delicate tissue, require greater tension to ensure good apposition of tissues. Have less knot security.
- Braided sutures: have more drag than monofilament sutures. They are often coated to reduce capillarity (Capillarity is the process by which fluid and bacteria are carried into the interstices of multifilament fibers).
- Polyglycolic acid, silk have degrees of capillarity (macrophages are too big to enter interstices = very small space)
- Monofilament are considered noncapillary: coating reduces capillarity.
- *Capillary sutures should not be used in contaminated or infected sites**
How is Knot tensile strength measured?
What is knot security, holding capacity?
- It is measured by the force in pounds that the suture strand can withstand before it breaks
- Sutures should be as strong as the normal tissue
- *Tensile strength of the suture should not greatly exceed the tensile strength of the tissue**
Relative knot security: is the holding capacity of a suture expressed as percentage of its tensile strength
Knot holding capacity of a suture: is the strength required to untie or break a defined knot by loading the part of the suture that forms the loop.
Tensile strength is the strength required to break an untied fiber with a force applied in the direction of its length.
How are Suture Materials Classified?
Structure
- Monofilament: less tissue drag, no interstices, break easily by needle drivers. Nonwicking, more memory, does not handle well.
- Multifilament: generally more pliable (ease of handling, adjust knot tension and secure knots) and flexible, may be coated. Wicking, less memory, good handling.
Behavior in Tissue
- Absorbable: degraded. Ex: Surgical gut, Chromic Gut. Lose tensile strength 60 days.
- Nonabsorbable: encapsulated or walled off by fibrous tissue.
Origen
- Synthetic: synthetic polymers broken down by hydrolysis
- Organic: Organic Absorbable CAT GUT = gradually digested by tissue enzymes and phagocytized.
- Metallic
Absorbable Organic Cat Gut Suture
What is is made of?
Does it elicit inflammation?
What is tanning?
Most common made from submucosa of sheep intestine or the serosa of bovine intestine. 90% collagen, broken down by phagocytosis. *Elicits a notable inflammatory reaction.
- Tanning (cross-linking of collagen fibers) slows absorption
- Increased tanning implies prolonged strength and reduced tissue reaction
- Available in plain, medium chromic, or chromic.
- Knots may loosen when wet
- Rapidly removed from infected sites, quickly degraded in catabolic patients
Synthetic Absorbable
What process brakes it down?
How does Alkaline environments influence it?
Which one is stable in infected wounds?
Which one is acceptable to use in E. coli contaminated area/urine?
-Polyglactin 910, Polyglycolic acid, Polydioxanone, Polyglyconate, Glycomer 631.
- Broken down by hydrolysis
- Minimal tissue reaction
- Not influence by digestive enzymes
- *Polyglactin 910 and Polyglycolic acid degraded rapidly in Alkaline environments but stable in contaminated wounds. Rapidly degraded in infected urine**
- *E. coli acceptable: Polydioxanone, Polyglyconate, Glycomer 631. **
- *Proteus spp. and P. mirabilis: accelerate degradation (7days).
Nonabsorbable Suture
- Organic
- Synthetic
- Metallic
- Silk: most common organic nonabsorbable. *Braided multifilament made by a special silkworm.
- Excellent handling, used in cardiovascular procedures.
- Coated or uncoated
- Does not maintain sufficient tensile strength after 6 months = not used in vascular grafts
- Avoided in contaminated sites
Synthetic nonabsorbable
- Braided multifilament: polyester or coated caprolactam
- Monofilament threads: polypropylene, polyamide, orpolybustester
- Typically strong and induce minimal tissue reaction
Cable ties
Should never be implanted in the body. Toxic substances released during degradation = abscess or tumor formation.
