Wound, Wound Healing and Closure Part 3

Surgical Techniques Affecting Healing

Length/direction of incision, dissection technique, tissue handling, hemostasis, moisture maintenance, debridement, dead space elimination

Incision Length/Direction

Long enough for sufficient operating space; best cosmetic results when parallel to tissue fibers

Sharp Dissection

Minimal trauma; cuts/divides cells; little adjacent cell damage

Scissor Dissection

Causes crush and tear trauma; relatively traumatic with adjacent cell damage

Tissue Handling Principle

Keep tissue trauma to minimum; gentle; use minimal tension; "DO NOT CRUSH"

Retractor Placement

Place with care to avoid excessive pressure; tension impairs blood/lymph flow and alters local physiology

Hemostats for Clamping Tissue

NO – causes crushing of cells; very traumatic; releases vasoconstrictors and clotting factors

Hemostasis Importance

Allows cleaner surgical field; prevents postoperative hematoma formation

Mass Ligation Risk

May produce necrosis and prolong healing time

Moisture Maintenance

"Dry tissue is dead tissue"; irrigate with warm physiological saline; cover with saline‑moistened sponges

Debridement

Removal of all devitalized tissue and foreign material; fragments increase infection probability

Dead Space Elimination

Use drains, suture layer by layer; prevents tissue apposition issues

Principles of Wound Management

Early/thorough care; individualized approach; consider antibiotics carefully; appropriate analgesia and restraint; tetanus prophylaxis in equines/ruminants

Wound Inspection

Thorough examination determines closure potential; hair clipping; sterile gloves/instruments

Wound Lavage Goals

Hydration, dilution of bacteria, removal of debris

Ideal Lavage Solutions

Lactated Ringer's, Normal saline, 0.05% chlorhexidine, 1% povidone‑iodine, tap water

Optimal Lavage Pressure

~9 psi using 18–19G needle with 35 mL syringe

Puncture Wound Lavage

Avoid pressurized lavage – risk of fluid tracking and edema

Surgical Debridement

Removes dead tissue and debris; preserves viable tissue (fascia, fat, muscle, loose bone fragments)

Aseptic Bandaging

Protects against infection; splinted bandaging for joint wounds; wet‑to‑dry/dry‑to‑dry for continued debridement

Topical Medications

Use only when indicated; avoid petrolatum‑based (slow epithelial healing)

Effective Topical Agents

Triple antibiotic, Silver sulfadiazine, Gentamicin, Trypsin‑based products, Sugar/honey, Aloe Vera, PRP

Primary Closure

Wound edges brought together at time of surgery

Primary Closure Indications

Clean or clean‑contaminated wounds with viable tissue and minimal tension

Primary Closure Contraindications

Grossly contaminated, infected, or containing foreign material

Tension‑Relieving Patterns

Vertical/horizontal mattress, near‑far‑far‑near

Sutures for External Closure

Non‑capillary synthetic (nylon or polypropylene)

Second Intention

Wound left open, heals from bottom up; slower, more granulation and scar tissue

Second Intention Indications

Wounds with contamination, extensive tissue loss, debris, or necrosis (best for body wounds)

Moist Wound Healing

Promotes optimal environment; enhances immune response, fibroblast activity, angiogenesis

Third Intention

Wound initially open until granulation bed forms, then closed with standard techniques

Third Intention Goal

Reduce healing time and improve cosmetic outcome

Third Intention Indications

Initially contaminated wounds that become clean; infected wounds after infection resolved

Drain Indications

Unobliterated dead space; high risk fluid accumulation; contaminated wounds/surgical areas

Passive Drains

Work via gravity/capillary; easy placement; exit through dependent site; short‑term use; not for abdominal drainage

Active Drains

Used for deep wounds requiring active evacuation; require airtight closure; risk of clogging

Penrose Drain

Passive drain with one end emerging from wound; removable via retention suture

Jackson Pratt Drain

Active drain system

Factors for Closure Decision

Classification of wound, local factors, animal's health status, timing of injury, owner's financial limitations