Principles of operative technique Flashcards
List Halstead’s principles
Gentle tissue handling accurate haemostasis preservation of vascularity surgical asepsis no tension on tissues approximation of tissues obliteration of dead space
What 4 basic techniques do all surgeries require?
incision and excision of tissue
maintenance of haemostasis
handling and care of exposed tissues
use of sutures, knots and other materials for closure and support
What instruments can be used to incise or excise tissue? 4
scalpel, scissors, electrosurgery, lasers
How can a steel scalpel be handled?
PENCIL GRIP - short, precise incisions
FINGERTIP GRIP - commonly used, larger incisions
PALM GRIP - when greater pressure must be applied
What sizes do scalpel handles come in?
3 (small), 4 (large) and size 7 (fine)
What scalpel blades are commonly used for the different sized scalpel blades?
For handle size 3/7, use blade 10 (curved), 11 (pointed) and 15 (small curve)
For handle size 4, use 20,21,22 and 23 (all curved)
What is press-cutting?
Use of s scalpel where you hold it in the pencil grip and apply pressure in the direction of the movement of the blade and is used to create incisions in hollow organs or cavities.
What is slide cutting?
A method for using the scalpel. Most commonly used and safest method of cutting and uses the pencil or fingertip grip.
What is sawing?
uses the pencil grip and allows a small incision to be deepend without removing the blade form the wound, but this method is traumatic and is more difficult to control depth.
What is craping?
analaogous to shaving hair or whiskers and may be used to develop pouches below the skin or fascia, to elevate muscles sub-peritoneally and to separate body cavity adhesions
After scalpels, what is the second commonest method to cut tissue?
Scissors
What are some different types of scissors and what are their uses?
Mayo = heavy scissors, for dense collagen rich tissue
Metzenbaum = fine scissors, for blunt dissection and sharp dissection of delicate tissues
Heavy suture scissors = use for large guage sutures to prevent dulling the blades of surgical scissors
Ligature cutting scissors = should be used for fine guage suture
When are scissors best suited? What about straight and curved scissors?
For cutting flaccid tissues not under tension and stabilise the tissues as they cut while allowing good control of depth. Straight scissors provide a much better mechanical advantage for cutting whereas curved scissors provide increased mobility and motility.
What are the 4 different scissor grips?
wide-based tripod grip
thenar eminence third finger grip
backhand grip thumb and third finger
backhand thumb-first finger
Which scissor grip describe using hte tips of the thumb and third finger int he ringers with the index finger on the shank for support?
wide-based tripod
When do you use a thenar eminence third-finger grip?
more useful for needle holders than scissors
What grip do you use to cut toward the surgeon’s dominant side?
backhand grip thumb and third finger
Which scissor grip do you use when making a cut towards the surgeon?
backhand thumb-first finger
What is ‘scissor cutting’?
uses the blades and is applicable to short incisions
What is ‘push cutting’?
suitable for long insicions in sheets of tissue. scissor blades are partially closed and then pushed through the tissue in one motion (tailor’s cut)
What is ‘blunt dissection’?
inserting closed scissor blades into tissue plance to be separated and then opening them. the scirssors are then withdrawn before closing the blades and repeating the manoeuvre. This is used for dissecting structing (vessels, nerves, muscle bellies) separated by more delicate tissue (fat, loose areolar fascia)
How does electrosurgery and lasers work? Benefits? Negatives?
transmit energy directly to tissues, resulting in vaporising of the tissue along the incision. there is greater collateral damage via thermal necrosis, but haemostasis may be provided
Advantages of electrosurgery
reduced blood loss (improved haemostasis)
decreased need for ligatures
reduced operating time
Disadvantages of electrosurgery
delayed wound healing and reduced resistance to infection
risk of fires and burns and the expense of the equipment
What does a continuous undamped sine wave provide?
maximum cutting with minimum coagulation and lateral thermal necrosis
What do interrupted, damped sine waves do?
maximise coagulation and minimise cutting
What are the different types of surgical haemorrhage?
primary - bleeding immediate
delayed intermediate - bleeding within 24 hours of surgery (e.g. slipped ligature)
delayed secondary - bleeding more than 24 hours after surgery (e.g. necrosis of ligated vessel)
Why is haemostasis important in surgery?
obscures surgical field
increases likelihood of infection
extravasated blood irritates tissues, delays wound healing and increases infection
preventive haemostasis avoids surgical panic which often causes more trauma
hypovolaemia and death possible
What is preventive haemostasis?
minimises primary haemorrhage (i.e. direct BV trauma)
How is preventive haemostasis done?
choosing a surgical approach that avoids major BVs
avoiding or retracting BVs
identifying BVs and provide haemostasis before cutting
gentle dissection
What surgical methods augment physiological haemostasis?
pressure with a swab temporary packing wound closure haemostatic forceps cautery and diathermy ligatures vascular clips and staples topical agents Tourniquet (Rumel)
What are the principles for the correct use of a swab? 7
use woven cotton swabs not pressed felt swabs
use swabs with radioopaque marker
use singly to encurage gentle use
use singly to reduce likelihood of leavingone behind
open swab out if performing a delicate manouevre
use large laparotomy swabs in body cavities
blot tissue, don’t wipe
What factors do you need to consider when deciding which haemostatic measure to use? 5
least traumatic least foreign material least necrotic tissue quickest depends on tissue
How do haemostatic forceps work?
they crush the tissue or vessel at the point of contact and have a ratchet so that they may be left inplace
What are different examples of haemostats? 4
Halstead mosquito (small)
Kelly (medium)
Carmal (Large)
Kocher (large with rat-toothed tip)
How do you achieve haemostasis in small vessels?
crushing or crushing with torsion before the haemostat is removed may be sufficient
How do you achieve haemostasis in larger vessels?
electrosurgery or ligation may be used after haemostats are applied
What points are important to consider when using haemostats?
the smallest forceps capable of accomplishing haemostasis should be used, the tips of the forceps are used to grasp the vessel and curved forceps are preferred since they place the tip in the line of sight.
What is another name for electrosurgery?
diathermy
How does diathermy work?
it passes an electric current through the tissue, producing heat as a result of tissue resistance. Other methods of cautery, such as hot irons and chemical styptics (silver nitrate) are not commonly used in surgery.
2 advantages of electrosurgery?
decreased operative time and reduced blood loss
What is monopolar diathermy? Advantages?
current flows between the handpiece (active electrode) to ground plate (indifferent electrode).
Advantages: ability to cut tissues as well as coagulation and the ability to apply current to instruments in contact with patient (conductive diathermy)
What happens in bipolar diathermy? Advantages?
the current passes between the two tips of the bipolar forceps.
The advantages include a lower current since a smaller distance is travelled, reduced local tissue trauma, reduced incidence of distant tissue trauma and burns are unlikely and it can be used effectively in a wet surgical field.
What knots should surgeons be aware of?
Simple knot - 1 single throw
Square (reef) knot - 1 single throw then another in opposite direction
Surgoen’s knot - 1 double then, then a single throw in opposite direction (to manage tension)
Half-hitch - 1 single throw, then another (square knot), but tightended by sliding (to manage tension)
Granny knot - 1 single knot, followed by another in same oreintation (AVOID - will loosen)
What ligatures can be used for vessels?
Simple, encircling ligature Double ligation ( 2 encircling ligatures or 1 encircling and 1 transfixing ligature) Halsted's transfixing ligature Modified transfixing ligature Tissue ligature (mattress suture) Stick ties (= tacking suture)
Define ligature
a piece of thread (suture) tied around an anatomical structure, usually a BV or other hollow structure to shut it off.
What is a vascular pedicle?
the tissues containing arteries and veins of an organ
What ligatures should be used for vascular pedicles?
Triple clamp technique (ligature tied into crushed area left by proximal clamp)
Modified Miller’s knot
Transfixing ligature
Division of pedicle (‘divide and conquer’)
What is a transfixing ligature?
Ligature passes through the tissue pedicle and round it
What is a modified miller’s knot?
end of ligature passes under loop of ligature - not commonly used
What happens in the divison of a pedicle?
the large vascular pedicle ligated as separate smaller pedicles
What is the triple clamp technique (ligature)?
ligature tied into crushed area left by proximal clamp
What are the 4 different types of haemostatic agent?
Agents causing:
vasoconstriction - ice saline, phenylephrine, adrenaline
promoting clotting - fibrin, collagen, cellulose, gelatin, polysaccharide
physical barrier - bone wax, glue
When should you use haemostatic agents?
Avoid if possible but use for liver and nasal biopsy (maybe because lots of blood?). Only collagen and bone wax are commonly used.
Name 2 types of tourniquet
Esmarch
Rummel
What are thumb forceps?
When to use them?
Why use them?
the instruments most often used to manipulate tissue
non-locking
spring-like action (opens jaws when pressure released)
Skin/dense tissues = Adson or Adson-Brown forceps
More delicate tissues = DeBakey
USES: stabilise tissue for incision or suturing retract tissue for exposure or incisions grasp vessels for electrocoagulation Pass ligatures extract needles pack swabs clear blood with swabs
What can tissue forceps be used for? 5
Stablising/retracting tissues = Allis (teeth), Babcock (no teeth)
Dissection of neurovascular strucutres from other tissue: Mixter, Lahey
Occlusion of hollow organs: Doyens (GIT), Rochester-Carmalt (uterus)
Occlusion of vessels and vascular pedicles: haemostats
Tangential occlusion of BVs after incision: Cooley, Satinsky
What are alternative methods of tissue manipulation that are less traumatic?
stay sutures skin hooks non-crushing forceps assistant's fingers/hands surgical swabs
What are the 2 groups of retractor?
hand held or self-retaining (ratchet or lockingmechanism)
What is the major disadvantage of retractors and what can be done to minimise this?
tissue trauma or ischaemia at point of contact
use a saline-soaked swab
What are alternatives to retractors?
packing organs off with sabs
exteriorising organs from body cavity
stay sutures
What are common hand-held retractors? 4
Senn
langenbeck
Army-Navy
ribbon malleable retractors
What are common self-retaining retractors?
Gelpi and Weitlaner (general surgery)
Finochietto (thorax)
Gosset and Balfour (abdomen)
What are examples of towel clamps?
Backhaus or cross-action
How can draped squares be secured to the patient’s skin? 3
towel clamps
Michel clips
sutures
What are the benefits of wound lavage?
removal of bacteria and FBs toxin dilution reduced wound infection tissue hydration improved visibility warming the patient
What is the ideal lavage?
sterile, isotonic, non-toxic, normo-thermic (38-42 degrees) solution and Hartmann’s solution or normal saline
ABs - no proven advantage
antiseptic - may be harmful
If lavage is used, the fluid must be completely removed, since bacterial opsonisation and phagocytosis is impaired in wound fluid.
How can fluid be removed from a wound?
suction tips such as Frazier (fine), Yankauer (wide bore) or Poole (multiple holes)
These are less traumatic than blotting with swabs and allows some estimation of blood loss
What can staples be used for?
close the skin, fascia and hollow viscera
What can be tissue adhesive be used for?
close the skin
What is suture closure usually performed with?
needle holder and thumb forceps
List some needle holders - 4
OSCES!!!!
Mayo or Mayo-Hegar (ratchet)
Olsen-Hegar (ratchet and scissors)
Gillies (scissors)
fine Castroviejo (ratchet)
Why do some needle holders and scissors have tungsten-carbide inserts in jaws or blades?
to provide durability and hardness of edge
How can knots be tied?
One-hand tie: rapid, within cavity, tendency to form a half-hitch
Two-hand time: reliable, more economical use of material
Instrument: most economical, lack tactile feedback
What are the principles of a successful suture? 6
Knot security is inversely proportional to suture diameter
Tighten each throw separately with even tension on both hands to avoid loosening
use absorbable multi-filament suture for ligatures
place minimum number of throws to reduce knot bulk
cut the ends short (3mm) to minimise foreign material in wound (cat gut 6mm)
avoid including frayed or damaged suture in the loop
What are methods to manage tension at closure?
surgeon's knit sliding half-hitch stay sutures for temporary approximation Galaban forceps Simple Square Always place 2-3 knots on top of a square or surgeon's knot
