Incisions and Retractions

Question 1

List Halstead’s Principles.

Answer 1

1. Gentle handling of tissue.
2. Meticulous haemostasis.
3. Preservation of blood supply.
4. Obliteration of dead space.
5. Minimum tension on tissues.
6. Accurate tissue apposition.
7. Strict aseptic technique.

Question 2

1. List scalpel blades.
2. Give the type of incision achieved by each.

Answer 2

1. 10, 11, 12, 15, 20.
2. 10 – long straight skin incision.
   11 – Stab incisions.
   12 – Stitch removal.
   15 – Thinner skin, curved incisions, areas where need to follow a contour e.g. paws.
   20 – Like a 10 but larger.

Question 3

Scalpel handling for more precise control, and for smaller blades. – What is achieved with this handling? – useful for?

Answer 3

Pen-grip with majority of hand beneath the holder and the thumb and index finger gripping holder. – Full thickness depth right into corners of incision. – useful for curves.

Question 4

Scalpel handling for long, straight incisions.

Answer 4

Grip with hand on top of the scalpel holder with index finger on top of blade and thumb and other fingers gripping holder. – A shallower angle using more of the belly of the blade (sharpest part of the blade).

Question 5

2 ways to make an incision?

Answer 5

Slide cutting
- Place tension on skin with free hand (non-dominant hand).
- One smooth incision using belly (curved bit) of the blade.
Stab incision
- One clean movement using point of the blade.
- May need to elevate tissue being incised, so don’t damage underlying structures e.g. linea alba.

Question 6

1. Aim when making an incision.
   – What can occur if there are too many blade strokes?
2. Why is it important to know your landmarks?
3. How do you achieve consistent depth throughout an incision?

Answer 6

1. Smooth incision, achieving full thickness in just 1 or 2 strokes. – jagged edges.
2. So you are confident in where and how long your incision should be.
3. How how firmly you press and alter the angle of the blade throughout length of incision. – press more firmly and at a steeper angle at the corners than in the middle.

Question 7

1. What should be avoided while incising where possible?
2. Where should the scalpel hand be placed while incising?

Answer 7

1. Blood vessels.
2. Hovering over the patient, not leaning on the patient.

Question 8

1. 2 methods of dissection.
2. Which is safer?
3. Consequences of excessive dissection?

Answer 8

1. Sharp and blunt.
2. Blunt.
3. Increased dead space and therefore increase infection risk.

Question 9

1. 2 ways to blunt dissect.

Answer 9

1. Digitally – Each index finger placed side by side in tissue plane and pulled in opposite direction.
   – Useful for deep dissection so you don’t damage tissues you can’t see.
   or with scissors.
   Scissors – Place tips in closed position in tissue.
   – Then open jaws parallel to tissue fibres or along natural tissue planes.

Question 10

1. What is haemostasis?
2. Why is haemostasis important?
3. 3 ways to achieve haemostasis?

Answer 10

1. Stopping blood flow.
2. Reduced blood loss.
   Increased visibility of surgical field.
   Reduced seroma and haematoma formation.
   Reduce dead space formation.
   Reduce risk of infection.
3. Mechanical
   Thermal
   Chemical

Question 11

1. Aim of mechanical haemostasis with digital pressure.
2. Action of mechanical haemostasis.
3. Advantage?
4. Not suitable for…

Answer 11

1. Stem flow for long enough that platelets to form plug (1-5 mins).
2. Direct pressure on vessel with a single gauze swab.
   or gauze packing in large defects.
3. Minimal trauma.
4. medium-sized or large vessels.

Question 12

1. Action of mechanical haemostasis using haemostats.
2. Give examples of haemostats.

Answer 12

1. Place perpendicular to the long axis of the blood vessel.
   Leave in place for at least 5 minutes.
   Hold in tripod grip.
2. Halsted mosquito forceps.
   Kelly forceps.

Question 13

1. Action of ligation?

Answer 13

1. Place haemostat prior to ligation with absorbable suture material.
   Use single circumferential for small vessels.
   Use 2 ligatures for pulsating or large vessels.
   - Can do circumferential with surgeon’s /
   sliding square / miller’s knot.
   - Can also use transfixing (distal to circumferential) in v large vessels.

Question 14

1. Other mechanical method for haemostasis.
   – Disadvantage of this method?

Answer 14

1. Use of soluble/sponge-type materials for low pressure bleeding, providing scaffold and promotes clot formation.
   – Can delay wound healing and promote infection.

Question 15

1. Method of thermal haemostasis?
   – Activity in tissues?
2. Methods of chemical haemostasis?

Answer 15

1. Diathermy/cautery. – Protein denaturation.
2. Adrenaline and potassium permanganate / silver nitrate.

Question 16

1. How does adrenaline cause haemostasis?
2. What is potassium permanganate / silver nitrate used for?

Answer 16

1. Potent a2-adrenergic agonist causes vasoconstriction.
2. bleeding claws.

Question 17

1. Why is tissue retraction important?
2. How do we achieve tissue retraction?

Answer 17

1. Increases exposure and visibility so reduces tissue trauma and surgery time.
2. Hand retraction i.e. assistant.
   Instrument retraction with hand-held retractors or self-retaining retractors.

Question 18

1. Which retraction method is preferred and why?
2. Name 2 types of hand-held retractors.

Answer 18

1. Instrument retraction as more gentle than hands.
2. Mathieu retractor, Hohmann retractor.

Question 19

1. Describe Mathieu retractor.
2. Describe Hohmann retractor.

Answer 19

1. Different ends – hand-like end perhaps for skin retraction and then flat blade end for deeper tissues e.g. tracheal surgery or TECA.
2. Blunt or sharp central “beak” for leverage of retractor against patient’s tissue to open surgical site e.g. ortho.

Question 20

1. How do self-retaining retractors work?
2. Give self-retaining retractors.

Answer 20

1. Blades of the retractors placed within incision and opened until tissues on each side of the incision are maximally spread.
   No assistant needed. Care to avoid damage with tips.
2. Gelpi retractor and Weitlaner retractor.

Question 21

1. How is max exposure achieved with Gelpis?
2. How do Weitlaners compare to Gelpis? – why?

Answer 21

1. 2 Gelpi retractors placed at 90 degrees.
2. Retract larger area of tissue so cannot be used in as small wounds as Gelpis. – multiple prongs.

Question 22

1. Consequence of incision not being long enough?
2. Points about tissue handling?

Answer 22

1. Bad exposure, increased tension, more tissue trauma.
2. Use natural tissue planes.
   Use sharp instruments
   Avoid excess undermining to reduce dead space.
   Handle tissues with appropriate instruments.
   Don’t let tissues dry out (beware theatre lights).

Question 23

1. What tissue type are Treves (rat-toothed) forceps used for? – why?
2. Adson forceps – tissue type, compare to rat tooth.
3. Describe Adson - Brown tissue forceps. – grip type.
4. Debakeys and other smooth tissue forceps – describe – tissue types. – Advantage?
5. Describe dressing forceps – When might these be used?

Answer 23

1. Dense tissue. – allow good grip without tissue slipping away.
2. finer tissues – less traumatic than rat tooth but like mini rat tooth forceps.
3. 2 longitudinal rows intermeshing teeth. – Broad yet delicate grip w/o major trauma.
4. Smooth longitudinal grips. – Delicate tissues e.g. bowel, blood vessel. – Least traumatic.
5. Smooth, flat, rounded forceps with transverse serrations for grip. – Where you really don’t want any punctures at all – e.g. cat spay as you might grasp GIT.

Question 24

How to hold thumb forceps.
Main use of thumb forceps?

Answer 24

Pencil grip.
Manipulate and stabilise tissue during incising and closing.

Question 25

1. Name some tissue forceps. 2. Why would these locking forceps be used?

Answer 25

1. Allis tissue forceps. Babcock tissue forceps. 2. Where prolonged tissue handling is required.

Question 26

1. Describe Allis tissue forceps. 2. Babcock tissue forceps.

Answer 26

1. Have saw-toothed edge and crush tissue so should not be used for delicate structures. 2. Less traumatic than Allis tissue forceps so can be used in more delicate tissue.

Question 27

Why would you lavage?

Answer 27

Decreases risk of infection as removes surface bacteria and debris. Moistening of tissues counteract dehydration from air and lights. Increased visibility by removing blood.

Question 28

How to lavage.

Answer 28

Use non toxic, iso-osmotic, normothermic fluid (warm it!) 0.9% sterile saline. For traumatic and/or infected wound, lavage under pressure (e.g. syringe with 18G needle). Antimicrobials can be added.

Question 29

Why use surgical suction.

Answer 29

If lavage, need to remove. Remove blood to increase visibility.

Question 30

1. Yankauer suction tip. 2. Poole tip

Answer 30

1. Wide diameter tip so used for larger volumes of fluid or thick fluid. One hole so potential for blockage. 2. Chosen for abdo lavage. Narrow diameter internal cannula with one hole at the end and an outer sheath with multiple holes. Gives gentler pressure suction. Can drain large volumes with minimal chance of blockage.

Question 31

1. What is a surgical drain? 2. Benefits of surgical drains?

Answer 31

1. Implant designed to channel unwanted fluids (wound secretions, pus, blood, urine) out of the body. 2. Facilitate elimination of dead space. Evacuate existing fluid and gas accumulations. Prevent anticipated fluid accumulation.

Question 32

Complications of surgical drains?

Answer 32

Foreign body response. Ascending infection. Patient interference. Decreased rate of healing.

Question 33

2 main drain types.

Answer 33

Passive (open) drains. Active (closed) drains.

Question 34

1. How do passive drains work? 2. Why does more irritation occur at the exit site? -- combat this? 3. 2 passive drain types?

Answer 34

1. Drainage by gravity and capillary action. 2. Fluid leaking inti skin. -- cover exit site with sterile dressing. 3. Penrose -- Fluid drains extra-luminally (along outer edge of the drain). Tube drain -- Extra and intra-luminal flow. Less common. Used in abdomen (not wounds).

Question 35

1. How do active drains work? 2. Compare to passive. 3. Disadvantage. 4. Give 2 types of active drainage.

Answer 35

1. By intermittent or continuous suction -- need a vacuum. 2. More effective at removing fluid, allows monitoring of volume and appearance of drained fluid, decreased risk of ascending infection, intra-luminal flow. 3. May cause damage to tissue due to high negative pressure. 4. Ready-made drain, tubing and collection reservoir. Large syringe as drain reservoir.

Question 36

Drain placement... 1. Where does proximal end of drain go? 2. Where does distal end of drain go? -- why? 3. How is distal end secured? -- Penrose. -- Active/tube. 4. Once placed...

Answer 36

1. Proximal end of drain placed inside wound and may or may not be anchored with suture. 2. Separate incision made for distal end. -- If exits via main incision, increase risk of wound dehiscence. (distal end must be descendent to facilitate drainage). 3. To skin with suture. -- Penrose = Simple interrupted. -- Active / tube = roman-sandal/purse-string. 4. -- Cut Penrose to length and cover with dressing. -- Connect active to reservoir, which is secured to patient's body/kennel.

Question 37

1. Care of passive drains. 2. Care of active drains. 3. When should an active drain be removed? 4. When should a passive drain be removed? 5. Recommended with penrose drains?

Answer 37

1. Change sterile dressing regularly. 2. Monitor fluid drained regularly. Record volume and appearance. Empty reservoir when necessary. 3. When fluid production reduces to 0.2ml/kg/hr. 4. When drainage reduces. **average = 2-4days.** 5. Record length in notes so can be measured on removal and check ends not torn to be certain all drain is removed. Penrose drains are normally radiopaque so can check on radiograph if concerned.