SurgerySterilization, Aseptic Technique, Surgical Instruments,

Wound Healing, Basic Suture Patterns

Controlling microbes

HIGH

LOW

Degree of control Technique

100% control Sterilization

99 – 100% control Disinfection

Up to 99% control Sanitization

Variable control cleaning

Sterilize, Disinfect, Sanitize, Clean

Objective is to control microorganisms (pathogens) to protect the patient

◦Can be found in the environment, fomites, each person, and the patient

◦Sterilization is the elimination of all life from an object (complete microbial control) Important in surgical environment

◦ Sanitizing and disinfecting often create acceptable levels of control

Definitions

Antiseptic-chemical agent that kills or prevents the growth of microorganisms on living tissue

Disinfectant- chemical agent that kills or prevents growth of microorganisms on inanimate objects

Sanitize -to make something free from dirt, infection, disease (pathogens) by cleaning, disinfecting, or sterilizing.

Clean- removal of dirt, and other unclean material

Methods of microbial control

Physical Methods

Chemical Methods

Methods of microbial control

Physical1. Dry Heat (oxidation)

Incineration-red hot/ fire Hot Air Ovens- 1 hour exposure to high heat (340)

2. Moist Heat (denatures proteins) Hot water – incomplete

◦Why do we add detergents –emulsifies oils and suspends soils…water is the universal solvent

Boiling – 3 hours for complete Steam (90 min) Steam under pressure (autoclave)

Autoclaves

autoclaving

Increase in pressure=increase in steam temperature=less time needed to sterilize

minimum 15 psi = steam at 121 degrees C (15 min)can get up to 35 psi = steam at 135 degrees C (1 min)

Steam and temperature indicators◦Did the steam reach everything in the autoclave◦Did the temperature reach target temperature (changes color)

Methods of microbial control

3. Radiation (damages cell/ dna) Ultraviolet-close range/ no penetration Gamma radiation

4. Filtration (physically traps organisms) Fluid filtration

◦Pore size of 0.45 microns removes most bacteria◦0.01 – 0.1 micron for viruses

Air filtration◦Surgical masks, air duct filters, HEPA (high efficiency

particle absorption) filters

5. Ultrasonic vibration- (disrupts cell walls/coagulates proteins)

Useful for cleaning surgical instruments prior to sterilization in autoclave

6. Cleaning –physical removal of organic and inorganic soils and microbes

Bell Work Monday April 21

List 5 physical methods of microbial control:

What is autoclaving? ◦Which physical method is it? ◦Minimum effective pressure is _____psi? ◦How long to achieve sterilization at this

pressure?

Chemical Methods of Microbial Control

Chemicals work by penetrating the organism cell walls and reacting with parts of the cell to destroy or inhibit growth.

Many chemicals are disinfectants with varying levels of activity; a few achieve sterilization

Remember Antiseptics are used on tissuesand disinfectants are used on inanimate objects

Chemical Methods: Contact Time is important!

Contact Time - The length of time an object is required to be exposed to a sanitizing or disinfecting agent before wiping or rinsing to ensure the effectiveness of the products’ kill claims.

Contact time for sanitizing is generally 2 minutes. (Check the Product label for contact times)

Contact time is 10 minutes for disinfecting.

Chemical Methods

1. Soaps and DetergentsSoaps in general have minimal disinfecting abilitySoaps can be used for cleaningDetergents emulsify oils and suspend particlesDetergents have some disinfecting ability

Chemical Methods

2. ChlorinesChlorine gas, chlorine dioxide, Sodium hypochlorite (household bleach)Disinfectant:most bacteria, viruses, protozoa, fungidisinfect water, inanimate objects…irritating to skin

Chemical Methods

3. Alcoholsethyl alcohol= 75% ethylisopropyl alcohol = 70% isopropylmost effective because of dilution with ethyl, isopropyl

◦ Useful as a skin disinfectant (antiseptic)◦ Irritating to tissues◦ Rapid antiseptic

Used as a solvent for other disinfectants and antiseptics(solvent: the liquid in which a solute is dissolved to form a solution)

◦ Ineffective after evaporation (which is pretty quick)◦ Porous surfaces such as furniture disinfectant

Both disinfectant and antiseptic

Chemical Methods

4. Peroxygen compoundsparacetic acid, hydrogen peroxide , benzyl peroxideoxidizing agentsactive against bacteria, fungiconsidered a sterilant, although there are some things it does not killbubbling action releases oxygen…helps to remove pus and cellular debris[benzyl peroxide-can be used on skin, as a shampoo, for pyoderma, keratyltic, antiseborrheic (flaky, itchy skin conditions)]

Chemical Methods

5. Halogensiodineiodine is used in solution with water or alcoholalcohol enhances antibacterial activity of

iodinekills bacteria, viruses, fungi, not sporesThe darker the color, the greater the activity

iodophorsiodine plus detergentused as surgical scrub-non staining/ non

irritatingBetadine, Povidone-Iodine

Antiseptic-used on tissues

Chemical Methods

6. Biguanides-Chlorhexadine gluconate -Has bacteriostatic and bacteriocidal properties, some viruses, fungi-Useful as a disinfectant and antisepticsurgical scrub of animal, wounds, skin, mouth, and inanimate objects/surfaces

 Nosocomial infections by Pseudomonas spp have developed from the use of contaminated chlorhexidine solutions in which the bacteria persisted

Chemical Methods

7. Quaternary ammonium compounds (Quats)benzalkonium chlorides, centrimide, roccal-disinfectant

-check formulations –bacteria/ some bacteria, some viruses, some fungi-roccal-parvovirus-inactivated by organic material, soap, hard water

Chemical Methods

8. Phenolscarbolic acid (C6 H5 O H), coal tar, Lysolsynthetic phenols are nonirritating/ non toxicDisinfectant…but in some formulations antisepticcheck labels: may be toxic particularly to cats, also rabbits and rodentsNot generally used as antiseptic, but sometimes combinedPine tar is a viscid blackish brown liquid, used primarily for antiseptic bandaging of wounds of the hoof and horn. Pine tar contains phenol derivatives that provide antimicrobial propertiesactivity decreased by quatsnot inactivated by organic matter, soap, or hard water

bacteria, some viruses, some fungi

Chemical Methods

9. Aldehydesformaldehyde, gluteraldehydeactive against bacteria, most viruses, fugi, bacterial sporesconsidered to be a sterilant, but may require 12 hours contact timeformaldehyde-can be diluted with alcoholtoxic/ irritant to tissue, respiratory tract

“Cold Sterilization”gluteraldehyde with 70 % alcohol is a potent germicide-useful for instruments, particularly endotracheal tubes, laryngoscopes, endoscopy equipment, rubber, plastics

Chemical Methods

10.Ethylene Oxide (EO)colorless, odorless gas, rapid penetrationflammable, explosive, toxic, carcinogenic, and irritantuseful against bacteria, viruses, fungi, bacterial sporesspecialized procedure-similar to autoclaving, but more specialized due to precautions

Which kill better?

High –cidalactivity

Low –cidal activity

Ethylene acids

Aldehydes

Paracetic acid/ chlorine dioxide

Halogens (iodine, chlorine)

Phenols

Quats (Roccal-D)

Alcohols

Chlorhexidine

Preferred Antiseptics

Why do we need to know how chemicals are grouped and their properties?

Antiseptics with antifungal activity◦Phenols, Chlorhexidine, Iodine, Povidone Iodine,

Sodium Hypochlorite (bleach), Cetrimide (quat)Antiseptics with antiviral activity

◦Isopropanol alcohol, ethyl alcohol, formaldehyde, sodium hypochlorite (bleach), phenols, H2O2 (hydrogen peroxide), iodophors (betadine)

Cleaning and Disinfecting of animal facilities

GENERAL GUIDELINES FOR CLEANING/ DISINFECTINGFor cleaning and disinfecting the following hard non-porous surfaces: including equipment, utensils, instruments, cages, kennels, stables, stalls and catteries.(Non- porous surfaces means they are solid and do not absorb any fluid…surface is non- penetrable.)

Remove all animals and feeds from premises, animal transportation vehicles, crates etc.

Remove all litter, droppings and manure from floors, walls and surfaces of facilities occupied or transversed by animals.

Thoroughly clean all surfaces with soap or detergent and rinse with water.

Saturate surfaces with an appropriate disinfectant for a period of 10 minutes.

Ventilate buildings and other closed spaces.

Do not house animals or employ equipment until treatment has been absorbed, set or dried.

Thoroughly scrub all treated feed racks, automatic feeders, waterers and other equipment which dispenses food or water with soap or detergent, and rinse with potable water before reuse.

Antiseptics and Disinfectants for hospital use (including veterinary)

DisinfectingDetergents for clothing, blankets, gowns (soak in water

prior)Sodium Hypochlorite (bleach) for clothing, gowns,

blankets, floors, blood spills, other objects and surfacesQuats and Phenols for floors, some surfaces (such as

Roccal for kennels)Chlorhexadine Gluconate formulated for surfaces,

instruments, kennelsGlutaraldehyde for instruments, laryngoscopes,

endotracheal tubes, endoscope (germicidal/sterilant)Surgical instruments: immersed, rinsed, ultrasonic

vibration, autoclaved---achieves sterility

Antiseptics and Disinfectants for hospital use (including veterinary)

AntisepticsHydrogen peroxide- removal of blood clots from

tubes, dressing/ cleaning wounds◦After a wound is cleaned, debrided, sutured up, use of

hydrogen peroxide can be detrimental because can cause destruction of healthy cells, also carries contaminants from outside sterile field

Ethyl alcohol (isopropanol alcohol)- can use at injection sites, has many advantages including rapid onset of action, synergistic with chlorehexidine, remember-irritant of tissues◦Furniture disinfection (furniture is a porous surface)

Antiseptics and Disinfectants for hospital use (including veterinary)

AntisepticsPovidone Iodine for surgical scrub of

patient, handwash/ presurgical hand scrub, dressings (wounds)

Chlorhexadine gluconate formulated as surgical scrub (synegistic with alcohol), can use in mouth (dilute), wounds◦Has residual activity, low toxicity

Some things to note:Contamination of chemical agents can

occur: For example Nosocomial infections

by Pseudomonas spp have developed from the use of contaminated chlorhexidine solutions in which the bacteria persisted

Always pay attention to proper concentrations- more is not better!

Physically remove organic matter as part of first step before moving on to disinfecting/ antiseptic use

Use the proper chemical for the situation

Bell Work Wednesday April 23

Here is a label from a quaternary ammonium compound. Interpret the label as best as you can:

Broad spectrum, hospital grade disinfectant cleaner and deodorizer.

Bactericide, virucide and fungicide. Effective at 1 oz. per gallon of water against antibiotic resistant bacteria, HBV, HBC, Avian Influenza, HIV and many others.

Effective in the presence of high organic soil and 400 ppm hard water.

ASEPTIC TECHNIQUE

Definition:Aseptic technique is a procedure used by medical staff to prevent the spread of infection. The goal is to reach asepsis, which means an environment that is free of harmful microorganisms. Each healthcare setting has its own set of practices for achieving asepsis. In veterinary medicine is most used for surgery of patients

Aseptic Technique: Where

Major procedures require a dedicated surgery room similar to what is used for human patients.

MAJOR SURGERY: Major surgery (e.g., laparotomy, thoracotomy, joint replacement, and limb amputation) penetrates and exposes a body cavity, produces substantial impairment of physical or physiologic functions, or involves extensive tissue dissection or transaction.

Aseptic Technique: Where

Many minor procedures use aseptic technique in a clean environment, such as

the treatment room

MINOR SURGERY: Minor surgery does not expose a body cavity and causes little or no physical impairment; this category includes wound suturing, and most procedures routinely done on an “outpatient” basis in veterinary clinical practice.

Aseptic Technique:

Initial procedures: ◦ preparation of surgical team, operating room, instruments,

patient

During surgical procedures: ◦ Contact of a sterile surface with other surfaces avoided.

Contamination prevention procedures:1. Cleansing and disinfection of operating room2. Preparation of incision site and draping the animal3. Aseptic preparation of the surgical team4. Sterilization of surgical instruments and materials

Prevention also includes responsibility of surgeon.◦ gentle handling of tissue and proper suturing technique

Like a chain, aseptic technique is only as strong as its weakest link…

Bell Work Thursday April 24

What is the definition of aseptic technique?Aseptic technique is a procedure used by medical staff to prevent the spread of infection. The goal is to reach asepsis, which means an environment that is free of harmful microorganisms.

What are some things that contribute to aseptic techniquepreparation of surgical team, operating room, instruments, patient, surgeon’s handling of tissues/ suturing surgical site closed

The patient

Preparing the patient◦Where the incision will be◦Clipping the area◦How to scrub◦Keeping the area around the animal sterile by

draping

Incisions

Some common incisions

1. Ventral midline incisionMost abdominal

surgeries

2. Paramedian –near midline (sagittal plane)

3. Paracostal incisionNear the ribs for

kidney or liver surgeries

4. Flank Incision

Identify useful landmarksprior to clipping fur for surgery

Sternum◦Manubrium cranially◦Xiphoid caudally

UmbilicusMidpoint of pubic bone (pubic symphysis)Rib arch (costal arch)

Preparation of the patient

Clip away hairWith #10 blade

Get rid of loose hairs

How do you know how much fur to clip?

Ask the surgeon◦Varies, 1 inch to 4 inches around expected

incision (on all sides)

◦Keep it neat (for the owner)

Surgical scrub of patient

Surgical Scrub of patient

Wet fur along borders so fur lays flat before beginningMost common antiseptics are chlorhexadine scrub,

povidone iodine, betadine, alcoholSterile water or alcohol commonly used as rinseTo begin scrub, start with where the incision will be and

continue in a spiral or circular pattern outward until you reach the end of the clipped area. The scrub is generally followed by either a rinse or use of a soaked sponge (gauze squares) of sterile water or alcohol to get rid of detergent.

This ensures that contaminants are moved from inside to outside

of circles…away from incision site

Surgical Scrub of patient

Recommended scrub solutions are chlorhexidine or povidone-iodine

Scrubs have detergent in them (must be rinsed off) and solutions have alcohol or sterile water

Your first preps would be with scrub and final would be with solution◦Detergents help clean skin (dirt and soils)◦Solutions have no detergent, correct concentration of

chemicalChlorhexadine has residual effect

◦ Chlorhexidine-alcohol mixtures are particularly effective in that they combine the antiseptic rapidity of alcohol with the persistence of chlorhexidine.  

◦ Povidone Iodine needs prolonged contact, so you usually don’t rinse off

Start with incision site and work away from site in circles.

Discard the gauze when you reach the end (the periphery)

There is no one correct method◦May use alcohol between detergent scrub and

non-detergent solution◦Each clinic will have its own protocol/ it’s own

procedure

Surgical scrub of patient

The scrub process is repeated. Patients are usually scrubbed three to five times.Why the repetition…contact time!

Some surgeons like the area to be dried after the final scrub and rinse. Accomplished with sterile dry gauze.

A final “paint” of betadine is often applied with spray or same process of scrub.

Ear prep

Clip◦Generally clip both sides of ear flap (pinna)◦If ear canal surgery clip side of face also

Antiseptics - ask surgeon◦Usual skin prep on ear flaps but may need to

plug the ear canals◦Use of antiseptics in ear canal may depend on

whether ear drum (tympanic membrane) is open or not

Paw Pads/ foot prep

Difficult to achieve asepsis in pads and under nails◦Clip nails◦Consider soaking whole foot in antiseptic for

several minutes◦Hold foot by placing a towel clamp into a long

toenail

Wound prep

1. Apply Sterile Lubricant (e.g. K-Y) into wound and onto surrounding hair

• it will wipe & rinse out well

2. Clip an outside ring first• Then clip towards the wound• Finally clip wound margins last

3. Rinse wound with sterile saline

Eye prep

Clip hair around eye-check with surgeon how much area to clip

Rinse eye with dilute betadine solution due to sensitive membranes

Final surgical skin prep around eye with betadine solution

Preparation of the incision site and draping the animal

Preparation of the incision site and draping the animal.

Principles of Draping 1. Isolate

Dirty from clean (e.g., unclipped fur on patient and equipmentfrom the area to be prepped). Isolation is accomplished byusing an impervious drape, usually fabricated from aplastic material. Any impervious material can be used.

2. BarrierProvides a first layer and/ or additional layer to prevent transport of microorganisms (microbes move by way of air or moisture/ fluid)

3. Sterile FieldCreation of a sterile field is through sterile presentation of the drape and aseptic application technique. Drape from sterile to unsterile…need to know sterile zones in reference to body, your position to the animal and your surroundingsIt goes without saying, a drape shall be free of dirt, organic

material, and lint and is made of certain acceptable materials that maintain the integrity of the principles of

surgery and sterility.

Handwash, gowning, gloving

http://partnersah.vet.cornell.edu/veterinarians/bovine/surgical-scrubbing-gowning-and-gloving

http://www.youtube.com/watch?v=mWHb48AflcY

Bell Work Monday April 28

What are some things that need to be done to prepare a patient for surgery?◦ Where the incision will be◦ How to clip the area◦ How to scrub the area◦ How to keeping the area around the animal sterile by draping

When scrubbing a patient, what pattern do we use and why◦Circular motion, start with incision and work outward, do

not overlap circles◦Bring bacteria out towards unsterile/ away from incision

site

Handwash

Before handwash begins prepare area by having all materials necessary

“Prep area” will contain items such as antiseptic cleaner, sterile hand towel, running water, ideally with “no hands” faucet, sterile gown, sterile gloves, face mask, surgical cap or bonnet

Handwash is first step in achieving aseptic technique in regards to the surgeon

Before Handwash begins…

Wear reasonably clean clothes and shoes

Tie loose hair back to prevent pathogens

Surgery cap and facemasks

Shoecovers

Remove all jewelry to prevent objects possibly penetrating gloves

It is recommended to wash and dry hands before beginning scrub process, clean under fingernails with disposable nail cleaner

Handwash

Mechanical component of scrubbing removes soils and organisms acquired from environment, direct contact

Chemical component reduces amount of, inactivates, inhibits growth of microorganisms

Handwash

Water is usually turned on by “hands free” methodIf prepackaged, scrub and brush are opened before

beginningScrub starting with hands, keeping hands elevated

which allows water to drip from elbowsScrub all surfaces, leave on to allow contact time

◦5 minutes◦According to manufacturer◦Count strokes

Nails 30 times each side of finger 20 times Back of hand, 20 times Etc

Hand wash

Start with thumb, each finger, back of hand, palm, over wrist, up the arm in thirds

Always keep in mind, four surfaces

Work way up arms to elbows (human medicine states 2 inches above elbows, veterinary medicine usually a couple inches below elbow)

Do complete hand and arm, before doing other hand and arm

Rinse hands and arms thoroughly

Getting ready to gown

Dry hands and arms with sterile towel continuing to use aseptic technique

Often times the sterile towel is placed in a package with a gown…the towel should be on top of the gown and is picked up without touching the gown

If you did not open packaging prior to scrubbing, an assistant needs to open the packaging for you (without touching the inside)

Drying hands

Discard the towel away from you and any other sterile items

Gowning

When picking up gown, the inside is considered unsterile and remains so

Remember although hands are scrubbed they are not sterile either

Unsterile to unsterile, so ok to touch inside of gown

Outside of gown is sterile-don’t touch◦exception is upper neck area and shoulders (axillary) and

back of gown

Gowning

Pick up gown by grasping inside of gown/placing hands into sleeves of gown◦When lifting gown out of package, stay clear of table or any

other unsterile obstacle that might inadvertantly come in contact with outside of sterile gown

Assistant then pulls up gown, using only “unsterile” areas of neck and shoulders, ties at back of gown.

Gloving will be next step◦ If using Closed Method of Gloving, sleeves and cuff stay over

hands◦ If using Open Method of Gloving, hands will be exposed

Gowning

Bell Work Tuesday April 29

What are some things you should do before beginning your handwash?◦ Set up prep area with sterile gown, sterile gloves, sterile

towel, handwash supplies◦ Remove jewelry, tie back loose hair◦ Cap, facemask, shoe covers◦ Change clothes/ shoes if particularly soiled◦ Wash hands, clean nails

Which parts of the surgical gown are considered unsterile and which parts are considered sterile?◦ Back of gown, inside of gown, axillary areas (upper shoulder,

neckline)◦ Front of gown and sleeves, sleeve cuffs

Gloving

Closed Technique◦No exposure of skin◦In veterinary medicine most often used for

orthopedic surgery, laparatomy

Open Technique◦Skin to skin, glove to glove

Open Technique without gowning◦aseptic technique, clean room

Open Technique

Once gowned and gloved…

Rules to observe while wearing sterile gown and gloves. NEVER

drop hands below the level of the sterile area at which you are working.

NEVERtouch surgical gown above the level of the axilla or below the level of the sterile area where you are working.

NEVERput hands behind your back; must keep them within full view at all times.

NEVERtuck gloved hands under his armpits, as the axillary region of gown is considered contaminated.

NEVERreach across an unsterile area for an item.

NEVERtouch an unsterile object with gloved hands

Where is sterile?

Opening sterile packs

A pack is a group of similar objects that are wrapped in cloth and then sterilized all togetherEx: surgery instruments,Gown and towel for drying hands

1

2

3

4

Maintaining sterility

Opening and pouring sterile fluidsAssisting with withdrawl of sterile solution

from a vial◦Outside of vial is contaminated from handling◦Contents are sterile and vial is unopened◦Assistant opens vial, maintains sterility

Adding sterile objects to a sterile field◦New pair of gloves for surgeon to reglove◦Additional instruments, sponges, suction,

additional suture material

Aseptic Technique:

A disinfected or sterile area

◦field = surgery site and adjacent areas, surgery table, area where instruments will be placed

◦Only sterile objects are allowed into the surgical field

◦Invisible “force field” / sometimes physical barriers (draping)

Summary of Aseptic Technique

Achieve sterility-Preparation of patient, surgeon, support staff, room, equipment

Scrubbed persons function within a sterile field

Maintain sterility

If contamination occurs during any part of the procedure, stop and correct the situation immediately.

Always maintain sterility

Other precautions for maintaining a sterile field are:1. Never turn backs on a sterile surface.2. An unsterile area not touched or leaned over.3. Sterile instruments never be below the edge of the surgical

table.4. Arms and hands remain above the waist and below the

shoulder.5. Lift up materials, do not drag over edges of containers.6. Keep all sterile surfaces dry.7. Avoid excessive movement during surgery.8. Avoid shaking of gowns, towels, drapes, and other materials.9. Keep conversation to a minimum during surgery.10. If waiting, clasp hands in front of your body above the waist.

If contamination occurs during any part of the procedure, stop and correct the situation immediately.

Bell Work Thursday May 1

True or False?◦The surgeon’s hands are considered sterile after

the handwash.True or False?

◦The method of gloving that was practiced yesterday was Open Method of Gloving.

True or False?◦The everted cuff on the sterile gloves is

considered sterile and that is why that portion can be handled by the surgeon after handwashing.

Surgical Instruments

Basic Anatomy of an instrument◦Finger rings◦Box lock◦Ratchet◦Shank◦Jaws◦Blade◦Serrations◦Teeth

Surgical Instruments

Hemostatic ForcepsScissorsNeedle HoldersScalpelsThumb forcepsMisc

Hemostatic forceps

Halsted mosquito forceps small, all the way up, small vessels

Kelly halfway, moderate sized vessels

Crile all the way up, moderate sized vessels

Hemostatic Forceps

Rochester -Pean Rochester -Carmalt

Rochester Carmalt

Both are used for large vessels such as arteries

Scissors

Sharp SharpBlunt SharpBlunt Blunt

Scissor

MayoDense tissue

MetzenbaumDelicate tissue

Special scissors

Lister Bandage Scissors Littauer Suture Scissors

Needle Holders

Olsen Hagar Needle Holders with scissors

Mayo Hagar Needle Holder without scissors

Scapel

Blade HandleScalpel Handle (#3)

Blades #10 and #11

Thumb forceps

Adson Tissue Forceps Adson Brown Tissue Forceps

Thumb forceps

Smooth Rat toothed

Other forceps

Allis Tissue Forceps Alligator forceps

Backhaus towel clamps

Spay Hook (snook)

Retractors

Gelpi Retractor Weitlaner Retractor

Retractors

Senn Miller retractors Balfour Retractor

And by the way…

Bell Work Tuesday, May 6

Lengthwise serrations on the jaws of hemostatic forceps are called:

Transverse Longitudinal

Describe Kelly hemostatic forceps Small, medium, large? Serrations in which direction How far up do the serrations go

Describe Rochester Carmalt forceps Small, medium, large? Serrations in which direction How far up do the serrations go

What is the difference between hemostatic forceps and thumb forceps?

Know your alcohol!Alcohol is neither a sterilant nor a high-level disinfectant.

Alcohol has been used historically for disinfection in a variety of species and situations. In certain cases, alcohol may actually achieve the desired outcome, but this is highly variable and inconsistent, since it depends on duration of contact time, agents being killed, contamination present on the skin surface, and organism life stage (vegetative organisms are killed more quickly than spores).

According to the Association for Professionals in Infection Control and Epidemiology, “ethyl alcohol and isopropyl alcohol are not effective in sterilizing instruments because they lack sporicidal activity and cannot penetrate protein-rich materials and cannot kill hydrophilic viruses.”

Surgery videos

http://www.youtube.com/watch?v=LEsK32zBUO0 7 minute video (instruments are easy to see, also suture)

http://www.youtube.com/watch?v=tWKuDbXZm5E very detailed…25 min dog spay

http://www.youtube.com/watch?v=LC7kyTXPqFs 4 minute dog castration

http://www.youtube.com/watch?v=IwRXXW3CU6s 45 minute video (more current, more “real”)

Note to self: Worksheet to go with 1st video…instrument identification

Bell Work Wednesday May 7

What is the purpose of a Backhaus Towel Clamp?

What is the purpose of Mosquito Forceps?

What is the purpose of retractors? Can you name one retractor?

Wound Healing

How wounds heal◦ Injury◦ Inflammation◦Organization◦Regeneration

1st intention tissue healing

2nd intention tissue healing

Seromas, hematomas and abscesses

3 stages of wound healing

1. Inflammatory Stage◦Hemostasis is included in this stage

Constriction of vessels to stop bleeding Dilation of vessels to bring oxygen and nutrients Release of histamine and heparin

◦The body’s initial/ immediate response to injury or trauma Smaller arteries and capillaries bring blood to the

area through circulation / bringing Oxygen and nutrients◦Rush of blood = extra fluid/ plasma =swelling and

inflammation

◦The blood brings in oxygen and nutrients for healing of tissue (epithelial tissues)

◦Clot Formation

◦Brings in white blood cells to fight infection ◦Pus is dead white cells◦Clot is formed

network of protein (fibrin)

◦This stage last about 2-3 days

3 stages of wound healing

2. Proliferation (Repair or Organization)◦Granulation Tissue forms-layers of collagen

fibers with new capillaries◦Forms under scab◦Has appearance of small granules

Very red, bleeds easily Called proud flesh in the horse when becomes too

thick are larger than wound Granulation tissue is resistant to infection because

it produces substances Can take 2-3 weeks

3 stages of wound healing

3. Remodeling (Regeneration)◦Epithelial cells are regenerating over the granulation

tissue (under the scab)◦Granulation tissue becomes more fibrous resulting in

a scar Scar tissue is thicker than original tissue Not as flexible as original tissue Does not perform same function as original tissue

◦Heart◦Muscles◦Organs

◦Can last 6 months to 2 years

Classification of wound healing

1st Intention Wound Healing◦Also called primary wound healing or closure◦Edges of wound are placed together in

apposition to each other.◦Very little to no granulation tissue therefore no

fibrous scar tissue

Classification of wound healing

2nd Intention Wound Healing◦Large wounds with tissue loss ◦Edges are separated◦Granulation tissue forms to close the gap◦Scar tissue formation

Scar Tissue

Scar tissue is undesireable◦Interupts normal tissue function

Cardiac tissue Skeletal muscle

◦Is thicker and can decrease the diameter of a lumen (space) Esophagus Intestines

Seroma

Seroma◦ A seroma is a pocket of clear serous fluid that sometimes

develops in the body after surgery. When small blood vessels are ruptured, blood plasma can seep. The remaining serous fluid causes a seroma that the body usually gradually absorbs over time (often taking many days or weeks); however, a knot of calcified tissue sometimes remains.

Hematoma

Hematoma◦ A hematoma is a localized collection of red blood cells outside

the blood vessels.

Abscess

Abscess◦ An abscess is a collection of pus (neutrophils) that has

accumulated within a tissue because of an inflammatory process in response to either an infectious process or foreign body. The body “isolates” the infection is a “pocket”.

◦ Great abscess video◦ http://www.youtube.com/watch?v=txET8DCFLn4

Drains

A Penrose drain, named for Dr. Charles Bingham Penrose, is a surgical drain which is left in place after a procedure to allow the site of the surgery to drain.

Facilitating drainage of blood, lymph, and other fluids helps reduce the risk of infection and keeps the patient more comfortable.

Pathogens-why do they exist?

Pathogens are opportunistic freeloaders? Pathogens are living organisms living within systems,

sometimes “our” systems Pathogens don't even need to try to cause contamination.

They thrive when the conditions (such as pH, temperature, water activity etc) are optimal for their growth. To stop them from contaminating, just make the conditions unsuitable for their growth.

Bell Work Thursday May 8

What are the three stages of wound healing?

Describe 1st intention healing.

Describe 2nd intention healing.

Suture

Materials

Patterns and tension

Knots

Suturing

Materials

Needles◦Straight, curved, half curved, half circle

Curved most common Described by circle size

◦¼ 3/8 ½ 5/8

◦Needle Points Cutting

◦Types of cutting points can be reverse, triangular or side cutting for skin, cartilage or tendons

Tapered (non cutting)◦Round or oval with reverse cutting points for tissue that

may tear easily

Curved needles

Cutting needle (triangular)

• Cutting edge is on inside of curve• Penetration of dense tissue• cut edge is where the tension is on the tied

suture so this type of needle predisposes the suture to cutting through the tissue

• use has generally been replaced by the reverse cutting needle

Reverse cutting needle

• cutting edge on outer surface of the curve • more efficiently uses the cutting surface when

curve wrist during insertion• more resistant to suture cutting through tissue

because the cut edge is opposite to the direction of tension on the tied suture

• preferred by most surgeons

Cutting vs Reverse cutting

Tapered or non cutting needle

• have a round body with a sharp pointed tip

• generally used for viscera, muscle and light fascia

• penetrates tissue, without cutting, creating a round hole

Materials

Suture Material◦Absorbable◦Non Absorbable◦Monofilament◦Braided◦Sizes

Absorbable suture material

Nonsynthetic◦ Cat gut or gut or chromic gut (coated with chromic salt)

natural fiber found in the walls of animal intestines◦ Sheep, goats, “cat”tle

Synthetic suture material:Made of various “formulations” to absorb◦ Vicryl (braided)◦ Monocryl (monfilament)◦ Ethicon◦ P.D.S◦ Maxon◦ significant loss of tensile strength by 14 days (rapid) -60 days

depending on which is used

Nonabsorbable suture material

Nonsynthetic◦Silk (could “absorb by 2 years)

Silkworm cocoon◦Stainless Steel

SyntheticDifferent formulations, some are coated, braided, monofilament◦Prolene◦Vetafil◦Ethicon ◦Ethilon◦Supramid

Sizes

Standardized labeling of sizes based upon diameter of thread:◦ Most veterinary suture material is smaller than #0 so the

“larger” the first number, the thinner the suture material is

◦ Examples: 6-0 is extremely thin, very fine 4-0 is thin (cats) 3-0 and 2-0 are common to use for routine surgeries 0 is thicker, used for tying off large vessels

◦ Why “ought”◦ As procedures improved, #0 was added to the suture diameters, and later,

thinner and thinner threads were manufactured, which were identified as ◦ #00 (#2-0 or #2/0) to #000000 (#6-0 or #6/0).

Suture Patterns

Interrupted Suture Patterns◦Simple interrupted◦Cruciate◦Horizontal mattress

Simple interrupted

http://emap-projects.usask.ca/vsac205/Lab3/lab/lab3_1.3.1.1.php

Properties:interruptedappositionalappropriate for normal tension on the incision's edgeslocal tension is managed by adjusting tension on individual suturesnot recommended if significant tensionminimal impact on the local blood supply to the incision's edges unless over tightened

Cruciate

Properties interruptedappositional patterna tension sutureless effect on blood supply than the horizontal

mattress but more than a simple interrupted

Suture Patterns

Continuous Suture Patterns◦Simple continuous◦Ford interlocking◦Lembert

Simple continuous

Propertiescontinuous appositional less effect on blood supply than the horizontal mattress but more than the simple interrupted

Why Knot?

The knot is the weakest part of a suture lineKnot security depends on

◦ the technique used to tie the knot◦ the physical characteristics of the suture material

A throw is the motion of wrapping the strands of the suture around each other and pulling on the ends to tighten them ◦ a simple knot consists of 2 throws (it tends to untie when under

tension)◦ a secure knot requires at least 4 throws (specific number varies

with how slippery the suture material is)◦ for continuous patterns, ◦ 5-6 throws are placed on the beginning knot while 5-7 are placed

on the ending knot◦ ends of the suture should be left long enough that they do not untie

(at least 3 mm, but varies with the suture size and material)

Common Instrument Knots

• most common method of tying knots• consistent• quick and adaptable• efficient use of suture

Square Knot Surgeon’s knot

Square Knot◦Wrap once, then once (2 throws)◦Tighten after each throw

Surgeons Knot◦Wrap twice, then once, then once (3 throws)◦Tighten after each throw

Fantastic vet site

University of Saskatchawan

http://emap-projects.usask.ca/vsac205/Lab1/lab1_intro.php