Wound Care: Types, Cleaning, Closure, and Infection Prevention

Introduction

Wound care involves the assessment, cleaning, closure, and monitoring of injuries to the skin and underlying tissues. Proper wound management reduces infection risk, promotes healing, and minimizes scarring. The skin is the body’s largest organ and its primary barrier against infection.

Wound Classification

Types of Wounds

Wound Type	Description	Mechanism	Examples
Abrasion	Superficial scraping of epidermis	Friction against rough surface	Road rash, skinned knee, floor burn
Laceration	Irregular tearing of tissue	Blunt force trauma	Cut from glass, knife wound, machinery accident
Incision	Clean, straight cut	Sharp object	Surgical incision, razor cut, scalpel
Puncture	Deep, narrow wound	Pointed object piercing skin	Nail, knife, needle, animal bite
Avulsion	Tissue torn away completely or partially	Shearing force	Degloving injury, ear partial avulsion, fingertip amputation
Contusion	Bruise, intact skin with underlying tissue damage	Blunt force	Black eye, hematoma, ecchymosis
Crush injury	Tissue compressed between forces	High-pressure compression	Industrial accident, car crash
Bite	Teeth puncture and tearing	Animal or human bite	Dog bite, cat bite, human bite (high infection risk)

Wound Depth Classification

Depth	Layers Involved	Characteristics	Healing Time
Superficial (partial thickness)	Epidermis only	No bleeding or minimal oozing, no scar	3-7 days
Partial thickness	Epidermis and dermis	Bleeding, painful, may scar	7-21 days
Full thickness	Through dermis into subcutaneous tissue	Fat visible, may require sutures, significant scarring	21+ days
Deep	Muscle, tendon, bone involved	Surgical repair required, high complication risk	Weeks to months

Hemostasis

Methods of Bleeding Control

Method	Technique	Indication
Direct pressure	Clean cloth/gauze pressed firmly on wound	Most wounds, first-line treatment
Elevation	Raise injured part above heart	Extremity wounds with venous bleeding
Pressure points	Compress artery proximal to wound (brachial, femoral)	Severe hemorrhage when direct pressure insufficient
Tourniquet	2-3 inches proximal to wound, tighten until bleeding stops	Life-threatening extremity hemorrhage, after direct pressure fails
Hemostatic dressing	Gauze impregnated with kaolin or chitosan	Severe bleeding, especially junctional areas
Wound packing	Pack gauze deep into wound cavity	Deep wounds with narrow openings
Pressure bandage	Elastic wrap over gauze	Ongoing oozing after initial control

Tourniquet Use

Aspect	Recommendation
Indications	Profuse bleeding not controlled by direct pressure, mass casualty, tactical situation
Placement	2-3 inches proximal to wound, NOT over joint
Tightness	Tighten until bleeding stops and distal pulse disappears
Time	Note time applied; do not remove until surgical care unless >2 hours
Commercial vs improvised	Commercial (CAT, SOFT-T) strongly preferred over improvised
Pain	Tourniquet is painful; do not loosen due to pain
Complications	Nerve injury, muscle damage, ischemia-reperfusion injury if prolonged

Wound Cleaning

Irrigation Solutions

Solution	Concentration	Indication	Comments
Normal saline	0.9% NaCl	All wounds, standard irrigation	Most physiologic, no tissue toxicity
Tap water	N/A	Moderate contamination when saline unavailable	Acceptable for most wounds, infection rates equivalent
Povidone-iodine	Diluted 1:10	Heavily contaminated wounds	Toxic to tissue if full strength; do not use in deep wounds
Hydrogen peroxide	N/A	Should NOT be used for wound cleaning	Tissue toxic, impairs healing, no proven benefit
Alcohol	N/A	Should NOT be used in open wounds	Severe tissue damage, pain

Irrigation Technique

Parameter	Recommendation
Volume	50-250 mL per wound depending on size and contamination
Pressure	5-15 PSI (use 18-gauge needle with 20 mL syringe for optimal)
Direction	Irrigate perpendicular to wound, from clean to dirty
Temperature	Room temperature or lukewarm
Brushes	Avoid scrubbing; use gentle pressure only for embedded debris

Wound Closure

Closure Methods

Method	Indications	Contraindications	Technique
Primary intention	Clean, fresh wounds (<8 hours, face <24 hours)	Infected wounds, animal bites, crush injuries, delayed presentation	Sutures, staples, adhesive strips
Secondary intention	Infected wounds, wounds with tissue loss	N/A (default when primary not possible)	Healing by granulation, wound packing
Tertiary intention (delayed primary)	Contaminated wounds, delayed presentation	N/A	Clean initially, pack, close after 3-5 days if clean

Suture Materials

Suture Type	Material	Properties	Indications
Absorbable	Polyglactin (Vicryl), Poliglecaprone (Monocryl), Polyglycolic acid (Dexon)	Hydrolyzed, loses strength over weeks	Deep dermal, subcutaneous, mucosal (mouth, vagina)
Non-absorbable	Nylon (Ethilon), Polypropylene (Prolene), Silk	Maintain strength, removed later	Skin closure, tendon repair
Monofilament	Single strand	Less tissue trauma, less infection risk	Vascular, skin (nylon, prolene)
Multifilament (braided)	Multiple strands twisted	Better knot security, more infection risk	General use, silk (not on skin)

Suture Timing for Removal

Location	Time to Removal (Days)
Face	3-5
Scalp	7-14
Chest/abdomen	7-14
Back	10-14
Arms/hands	7-10
Legs	10-14
Feet	12-14
Over joints	10-14

Bandaging and Dressing

Primary vs Secondary Dressings

Type	Purpose	Examples
Primary (contact layer)	Direct contact with wound, maintains moist environment	Non-adherent pads, hydrocolloid, foam, alginate
Secondary (absorbent layer)	Absorbs drainage, protects primary dressing	Gauze, ABD pads, roll gauze
Tertiary (fixation layer)	Holds dressing in place	Medical tape, elastic wrap, tube gauze

Dressing Types by Wound Stage

Wound Stage	Moisture Level	Recommended Dressing
Hemostasis	Dry/minimal exudate	Non-adherent pad, gauze
Inflammatory	Light exudate	Transparent film, hydrocolloid
Proliferative (granulation)	Moderate exudate	Foam, alginate
Epithelialization	Minimal exudate	Hydrocolloid, thin foam
Contaminated/infected	Heavy exudate, debris	Alginate, hydrofiber with antimicrobial

Specialized Dressings

Dressing Type	Composition	Indications	Change Frequency
Hydrocolloid	Gelatin-pectin matrix	Light-moderate exudate, pressure ulcers	3-7 days
Foam	Polyurethane	Moderate-heavy exudate	2-4 days
Alginate	Seaweed-derived calcium	Heavy exudate, packing cavities	Daily or when saturated
Hydrogel	Water-based polymer	Dry wounds, burns, necrotic tissue	Daily
Transparent film	Polyurethane	Superficial wounds, IV sites, donor sites	3-5 days
Silver-containing	Silver ions/impregnated	Infected wounds, high bacterial burden	Up to 7 days
Honey	Medical-grade honey	Infected wounds, burns	Daily
Negative pressure (wound vac)	Foam + suction	Chronic wounds, dehisced surgical wounds	Every 48-72 hours

Signs of Wound Infection

Local Signs

Sign	Description	Timing
Erythema	Redness spreading beyond wound edge	24-72 hours post-injury
Warmth	Increased temperature of wound area	Ongoing
Edema	Swelling beyond initial trauma	Ongoing
Pain	Increased or uncharacteristic pain	Ongoing
Purulent drainage	Yellow/green/brown exudate	Ongoing
Foul odor	Unpleasant smell from wound	Ongoing
Induration	Hardness of tissue surrounding wound	Ongoing
Lymphangitis	Red streaks tracking proximally from wound	Systemic spread
Wound dehiscence	Wound edges separating	Late sign

Systemic Signs

Sign	Implication
Fever (temperature >100.4F / 38C)	Systemic infection
Chills	Bacteremia possible
Malaise	Systemic inflammatory response
Tachycardia	Possible sepsis
Tachypnea	Possible sepsis
Altered mental status	Serious infection in elderly

Cellulitis vs Necrotizing Fasciitis

Feature	Cellulitis	Necrotizing Fasciitis
Pain	Moderate	Severe, out of proportion to exam
Skin appearance	Erythema, warm	Bullae, duskiness, necrosis
Crepitus	Absent	Gas in tissue (present in 50%)
Systemic toxicity	Mild-moderate	Severe, rapid progression
Laboratory	Mild leukocytosis	Severe leukocytosis, acidosis, elevated CK
Treatment	Oral/IV antibiotics	Emergent surgical debridement + IV antibiotics
Mortality	<1%	20-40%

Tetanus Prophylaxis

Tetanus Wound Classification

Wound Characteristic	Tetanus-Prone	Clean Wound
Mechanism	Puncture, crush, burn, frostbite, avulsion, missile	Clean incision, abrasion
Time since injury	>6 hours	<6 hours
Contamination	Soil, feces, saliva, rust, debris	Minimal contamination
Devitalized tissue	Present	Absent
Depth	>1 cm deep	Superficial

Tetanus Prophylaxis Guide

Vaccination History	Clean, Minor Wound	All Other Wounds (Tetanus-Prone)
Unknown or <3 doses	Tdap + TIG	Tdap + TIG
3+ doses, last <5 years	No prophylaxis	No prophylaxis
3+ doses, last 5-10 years	Tdap (or Td)	Tdap (or Td)
3+ doses, last >10 years	Tdap (or Td)	Tdap (or Td) + TIG

TIG = Tetanus immune globulin (250 IU IM); Tdap = tetanus, diphtheria, acellular pertussis; Td = tetanus, diphtheria Tdap is preferred over Td for adults who have not received Tdap previously

Wound Healing Process

Phases of Healing

Phase	Duration	Key Events
Hemostasis	Immediate to hours	Platelet aggregation, clot formation, vasoconstriction
Inflammatory	0-72 hours	Neutrophils and macrophages arrive, debris clearance
Proliferative	2-21 days	Fibroblasts produce collagen (granulation), angiogenesis, epithelial migration
Maturation (remodeling)	21 days - 2 years	Collagen remodeling, scar maturation, strength increases to 80% of original

Factors Affecting Healing

Factor	Effect on Healing
Age	Slower healing with advanced age
Diabetes	Impaired microvascular circulation, delayed healing
Smoking	Vasoconstriction, reduced oxygen delivery
Malnutrition	Protein, vitamin C, zinc deficiency impair healing
Steroid use	Anti-inflammatory effect slows healing
Infection	Delays all phases of healing
Immunosuppression	Impaired inflammatory response
Locally impaired circulation	Peripheral vascular disease, venous insufficiency

Wound Care Procedure Summary

Step	Action	Rationale
1	Control bleeding	Direct pressure, elevate, tourniquet if necessary
2	Assess wound	Type, depth, contamination, neurovascular status
3	Clean wound	Irrigate with saline, remove debris
4	Explore wound	Assess for foreign body, tendon/vessel/nerve injury
5	Close or pack	Primary closure (sutures/staples) vs secondary intention
6	Dress wound	Appropriate dressing for wound type
7	Pain management	Analgesia as needed
8	Tetanus prophylaxis	Based on vaccination history and wound type
9	Antibiotics	Prophylactic (high-risk wounds) vs therapeutic (infected)
10	Aftercare instructions	Signs of infection, dressing changes, follow-up

Special Wound Considerations

Human Bites

Aspect	Management
Infection risk	Very high (Eikenella corrodens, oral anaerobes)
Closure	Do not close primarily (except facial wounds)
Antibiotics	Prophylactic amoxicillin-clavulanate (or clindamycin + TMP-SMX)
HIV/HBV prophylaxis	Consider depending on source
Hand wounds	All require evaluation; high complication rate

Animal Bites

Animal	Common Pathogens	Antibiotic Prophylaxis	Rabies Concern
Dog	Pasteurella, Staphylococcus, Streptococcus	Amoxicillin-clavulanate	Low in domestic, high in strays/wild
Cat	Pasteurella multocida (high incidence)	Amoxicillin-clavulanate	Low in domestic, high in strays/wild
Human	Eikenella, oral anaerobes	Amoxicillin-clavulanate	No rabies concern; HBV/HIV risk
Bat	N/A	Per wound type	HIGH rabies risk - always seek prophylaxis
Raccoon/skunk/fox	Various	Per wound type	HIGH rabies risk

Puncture Wounds

Aspect	Management
Cleaning	High-pressure irrigation through puncture opening
Exploration	Determine depth, assess for foreign body/retained object
X-ray	Indicated if glass, metal, possibility of retained object
Soaking	Do NOT soak (increases infection risk)
Closure	Do NOT close primarily
Tetanus	High risk; ensure prophylaxis
Antibiotics	Consider if wound is through athletic shoe (Pseudomonas risk)