الثالثة المرحلة الرابعة المرحلة

• kufa-university

Wound

Surgery /Dr. H. Zaini

kufa / university wound Healing Mechanism of wound healing

Stage 1: homeostasis•Duration: 1st 4 hrs•At time of injury, there is transient vaso consiction of arteriole, mediated by neurogenic reflex that lastfor seconds or minutes according to degree of injury.•And there is change in the charge of damagedcollagen which lead to immediate activation of clotting system & stimulate platelet aggregation produce fibrin plug, then form a scab which seal the wound from outside.

Stage 2: inflammation •Duration: 1st 24 -48 hrs•Following transient vaso constriction, there is prolong period of vaso dilation mediated by histamine & tissue mast cellswith activation of complement & kin in systems.•The PMNs migrate in to the wound to phagocyte damaged tissue and bacteria competing infection & removing excess blood clot with formation ofinflammatory exudates.•Clinically the wound is,

*Red *painful *warm *Edematous

Stage 3: Granulation tissue formation

•Duration: 48hrs -5 days •This stage characterized by emergence of macrophage as predominant cell within injured tissue and gradual disappearance of neutrophills.•Granulation tissue is soft, pink, granular appearance on surface of the wound that is proliferating matrix of fibroblast & macrophage with new blood vessels with collagen & ground substance that consist mainly of mucopolysaccharids.•At the margin on the surface of the wound, the deeper layer of the wound edge myofibroblast, contracted reducing surface area of the wound.

Stage 4: Maturation• Mean scar formation (Duration 5days – months)

• Long process consists of collagen strengthening, remodeling & re-alignment of collagen fibers.

• The result is acellular, avascular collagen scar.

Staging of scar

Stage 0 (First 4 weeks)

Start with red, thick , weak, with edema

Stage 1 (4-12 weeks)

Pink, thin, strong

Stage 2 (12 weeks- 40 weeks)

• Pale, thin, very strong• Take color of skin • End stage of scar• The appearance of scar depend on a. Age of pt . b. Race of pt. c. anatomical side

of the wound.

A. In younger & older ages, there is more ugly scar.B. In Negro races the scar is more ugly than white

races.C. Scar in ear lobe, sternum & shoulder is more

ugly & hypertrophic than other sites .

Types of wound healing There are 2 types of wound healings.

1. Healing by first intention (primary union)

•The clean surgical incision generally heals in this way.

•There are usually been minimal tissue loss with minimal bacterial contamination.

• The divided tissue edges are re-approximated either by suture or clips without tension.

2. Healing by second intention (secondary union)

• Wound with more extensive defect between edges with tissue loss caused by surgical excision (removal of tissue) or trauma, with heavy wound contamination compared to healing with first intention. • There is more fibrin exudation & there is more necrotic tissue & prolong inflammation with greater production of granulation tissue.• There is wound contraction which is minimal in primary union but play major role in decrease size of tissue defect with heading occur by secondary union due to presence of more myofibroblast than primary union and there is more scar formation & so become more ugly especially in burn. *clean incision --nice scar**more tissue loss --more ugly scar*

Wound strength

•Most wound never return the pre injury strength which is reach 70-80% of pre injury strength by 3 months & remain stationary or may decrease.

•But at the beginning the strength increase by 40-70% of pre injury strength by suture.

•So that the exercise avoided until 3 months of the injury.

•After removal of suture at time of 10th day postoperative, the strength of wound return to 10% & gradually increase to reach 70-80%.

Factors affect wound healing A. systemic

1.Nutritional status Deficiency of vit. C ,A, protein, zinc, or other element.2.Steroid therapy anti – inflammatory drugs.3.Anticancer chemotherapy anti- mitotic.4.Ionizing radiation cause killing of growing cell.5.Uremia or any toxic material.6.Jaundice serum bilirubin (cause poor wound healing).7.Malignant disease.8.Diabetes mellitus.9.Aging All these factors cause poor wound healing.

B . Local•Related to wound 1)Infection whatever type of infection.2)Ischemia mean poor blood supply whatever the cause.•Hematoma, arterial disease (anemia, shock), tension suture, compartment syndrome all increase pressure & cause ischemia. *compartment syndrome*•The condition that result from swelling of the muscle in a compartment of a limb , which raise the pressure within the compartment so that the blood supply to the muscle is cut off, causing ischemia & further swelling.•So compartment is tissue that enclosed by deep fascia.3)Foreign body whatever the type of F. B.4)Malignancy in both general & local factors.

Management of wound

“General principle of Rx of “ “wound”

(A ) closure or suturing

•For any wound the most important is to avoid development of infection, therefore all wound should clean & necrotic tissue & debris removed.

•The decision about wither to close the wound immediately or leave it open determined by degree of wound contamination & tissue loss.

1. Primary closure

•Surgical incisions are first manage by primary closure using

suture or adhesive tape.

•Ragged wound required surgical excision of edges followed by

primary closure, if this can achieved without tension.

2. Delayed primary closure

Wound with abundant crush or devitalized (dead) tissue

required more extensive wound excision. The wound

can be left open for infection to be subsided and if tissue

viable & clean, then wound may close at 3-5days by delayed

primary closure.

3. Secondary closure.

If there is a lot of infection and discharge of

leave the wound open until clean from bacteria & surrounded

infection for 10-14 days (average 12 days) them sutured without tension.

Grafting tissue Skin graft of 3 types:

1. Primary skin graft • At time of visit

from beginning, after injured area cleaned from damaged tissue , as after burn, at time of presentation can be healed or closed by primary graft.

2. Delayed skin graft after 3 – 5 days

3.Secondary skin graft

After weeks when there is no bacterial contamination, then can closed when there is good granulation.

War injury •It is two types:1)Low velocity missiles2)High velocitymissiles•The difference in speed of bullets, shell or missiles.•If more than 600m.\sec. speed regarded as high velocity.•It causes more damage than low velocity due to phenomena called “temporary cavitations”.•In low velocity injury occur only along bullet tract.•In high velocity injury not only along it’s tract but causing negative pressure in the area and separate the edges due to *high energy & *high speed.

And so leaving large cavity “temporary cavitations “.

• The inlet is small & outlet usually more than inlet in size and there is large cavity within tissue that withdraw a lot of things from outside as cloths, dust, & other causing more trauma.

• So in high velocity injury usually:

1) Not closed 2 )Wound excision and left open & remove

necrotic tissue & foreign bodies & should not closed by primary closure but by delayed or secondary closure .

Factors affect wound healing

•Site of wound

•Mechanism

•Structures involved

•Contamination (foreign body , bact.)

•Loss of tissue

•Other local --- vascular insufficiency, previous radiation , pressure.

B. Antibiotics a) Prophylactic

• Given before occurrence of infection• According to area of injury

b) Therapeutic• Given after occurrence• According to culture & sensitivity

Complications of wound healing

1) Infection •It occurs according to type of injury as in garden area, street, war, surgery and other. •Each has specific bacteria to it.•Ex: in surgery staph. & strep. More common in open GIT endogenous bact. mostly anaerobic .2) Dehiscence •Mean the wound is opened, whatever the cause :-

*surgeon *surgical technique *type of operation

*type of suture *type of closure•Usually occur between 6-10 postoperative days when the strength of wound is at weakest.

3) Fibrosis Mean excessive fibrin production that start by fibrinous & end by fibrous tissue that cause:- *in skin ugly scar. *in abdomen, chest, intestine, (internal organs) adhesion & other complication. 4) Over healing

There are 2 types of over healing that mean maturation of scar.

a. Hypertrophic scar• That over healing usually has time limit up to 6 months.• Not exceed edges of the wound.• Usually respond to steroid & excision .

b. Keloid• That over healing usually has no time limit.• Progress and spread to surrounding area.• Not respond to excision.• May be treated by irradiation or steroid injection.

Note

•Debridement removal of clear necrotic tissue and less extensive than wound excision

•Wound excision removal of clear necrotic tissue & near tissue that less vascularized because it is good culture for bacteria.

Trauma In general, when see any traumatized

patient should put following important things in your mind :-

(A) Initial Assessment

1. Primary survey

* It includes :-

(A )Airway•Important to keep clean once receiving traumatized patient.•Should be made patent by open the mouth & look for any abnormal thing in mouth that may close airway & remove it.•If unable put oral airway.•If unable put endotracheal tube.

(B) Breathing•Look for chest moving for respiration or not &•If not, should put oxygen mask or mouth to mouth breathing.

1. Give 100% oxygen at high flow.2.Check for tension pneumothorax.3.Decompression need .

(C) Circulation• To maintained by intravenous line by canulation or another way.

• I.v. fluid or plasma expander or blood, that maintained blood pressure ,so looking for :-

1.Conscious level2.Skin color3.Pulse,----

(D) Drug or Disability include, Neurological problem due to fracture or other

injuries .

(E) Exposure mean Environmental exposure to remove the tight

clothes .

2. Resuscitation a. Shock management :- *should be supplemental o2 initiated for trauma pt. * minimally of 2 large borne peripheral intravenous catheters or canulas & establish i.v. Fluid that usually start with normal saline (electrolyte solution remain in circulation within half hour that used to maintain Bp ) .The plasma expander should not be given before cross matching because interfere with cross match of blood & interfere with RBC agglutination (e.g. Haemacele which is gelatinous fluid ). B. Continuing Management :-continuation of primary survey & maintenance of o2 ,i.v. fluid, urinary catheter ,nasogastric tube----

C. Monitoring every trauma pt. when present should prepare a chart containing (Bpr. , name , age , gender , output , input , notes)- output whatever fluid lost from patient (urine, diasshia,..)- input how much fluid given for patient.-notes result of each half hour examination that can determine triage of patient (improving or deteriorating)

*Also include other examination as droplet of blood in external urethral meatus that mean partial or total rupture of urethra & so should not put the urethral catheter, because may cause complete cutting in case of partial rupture.

*patient (especially multiple injured patient) should rectal examination (pr)’ or for assessment of prostat.

3. Secondary Survey* Once finished to save life there should be revaluation started from head to toes.

* It start from head & face pallor, cyanosis, trauma at back.

* Then the cervical spine & neck because may lead to death of patient if moved without cervical collar so should support during transfer.

* Then the back that should supporting during transfer also.

* Neurological examination of motor & sensory as touch & pain &---- especially in head injury .

4. Definitive Care * It done accordingly. *In abdominal problem laparatomy may made. *In chest injury chest tube. * In head injury neuro surgery. *Lower & upper extremities injury as feature of compartment syndrome & orthopedic surgery.

5. Transfer* In our society the transfer is not in a good way .

* In road traffic accident that there may be a lot of loss within hour.* Classify Triage in area of accident and transfer patient by trolley that need specific bands to support patient.

* so the way of transfer should be in a good way from area of accident to near hospital.

*And once pt. stabilized in general hospital , it should transfer to specialized hospital.

* Within transfer management should be continued.