Wound Healing and Closure Gil C. Grimes, MD

Goals Review anatomy of skin Basics of wound healing One and two handed tie Instrument ties and deep ties

Brief Anatomy

Lines of Tension Static lines Langer’s Lines Reflects natural skin tension Worst along anterior tibia Best along volar surface of hand Can be tested with pinch test Wound gap >5 mm demonstrates significant tension

Lines of Tension Dynamic Kraissl’s lines Formed by movement Compression of skin Everyone smile If you can cut parallel to these then lessen scar

Wound Healing Hemostasis Tissue retraction Tissue compression Vasoconstriction Clotting cascade Vascular dilation Wound exudate

Wound Healing Inflammation First phase Compliment attracts granulocytes Peaks in hours Over by 72 hours Second phase Macrophage driven Begins 24 hours Peaks 5 days Phagocystosis Returns nutrients Stimulates fibroblasts and endothelial cells

Wound Healing Epithelialization Begins at 12 hours In closed wound seal formed by 24 hours Unclosed wounds close slower Remember road rash

Wound Healing Neovascularization Evident by day three Most active by day 7 Decreases by day 21 New capillary loops are surrounded by active fibroblasts Give granulation tissue its color

Wound Healing Collagen Synthesis Mitosis fibroblasts begin day 1 New collagen laid down day 2 Peak synthesis day 5-7 Initial pattern random Remodeled over time

Wound Healing Return of tensile strength Weakest at day 7-10 due to remodeling At 35% of original strength at 30 days At 70 % of original strength at 70 days Never completely as strong as the original

Comorbidities to healing Age Dermal component Muscle mass Inflammatory response Collagen deposition Tensile component Circulation

Comorbidities to healing Weight and Nutrition Increases stress Adipose has poor blood supply Malnutrition Blood Supply Oxygen delivery Smokers CHF and CAD

Comorbidities to healing Immune system HIV Steroids Allergies Chronic Disease Diabetes Peripheral vascular disease Malignancies Infection

Types of Wounds Shearing Force Incisions Due to sharp objects Minimal collateral tissue damage Sharply defined margins Minimal localized devitalized tissue

Types of Wounds Tension Force Laceration Tearing forces Blunt or semi-blunt object strikes at an acute angle Creates a flap Shearing force transmitted to surrounding tissue

Type of Wounds Compression Blunt object strikes at a right angle Lots of collateral tissue damage Significant devitalization of surrounding tissue Subcutaneous tissue very susceptible to injury Adipose necrosis

Wound Closure Primary Within the first 6-8 hours May delay longer in select locations Face and scalp may be delayed to 24 hours Lower extremities may need to be closed sooner Must have a fresh wound May freshen wound If it is clean and bleeding it can close

Wound Closure

Steps to Closure Asses patient Wounds can wait if other problems exist Prevent further injury Clean the wound Allergies Anesthesia Tetanus

Steps to Closure

Good Knots

Square Knots

Instrument Tie

One Handed Tie