Why is iodine wash no longer used for routine wound dressing and reserved for cases with infection, foul smell, pus, necrotic tissue, or autolytic debridement, with saline wash being the preferred standard cleaning method?

Evolution of Wound Cleansing Practices: From Iodine to Saline

The shift from routine iodine use to saline for wound cleansing represents evidence-based practice that prioritizes wound healing while reserving antimicrobial agents for specific clinical indications.

Current Best Practice for Wound Cleansing

• Clean wounds regularly with clean water or saline, and dress them with sterile, inert dressings to control exudate and maintain a warm, moist environment for optimal healing 1
• Select dressings principally based on exudate control, comfort, and cost rather than antimicrobial properties 1
• Reserve antimicrobial dressings (including iodine-based products) for specific clinical indications rather than routine use 1

Why the Change from Routine Iodine Use

Evidence Against Routine Antimicrobial Use

• Current guidelines strongly recommend against using antimicrobial dressings with the goal of improving wound healing or preventing secondary infection 1
• The International Working Group on the Diabetic Foot (IWGDF) explicitly states: "Do not use antimicrobial dressings with the goal of improving wound healing or preventing secondary infection" (strong recommendation, moderate evidence) 1
• No evidence supports one form of topical agent over another for routine wound care 1

Specific Indications for Iodine

Iodine is now reserved for wounds with:

1. Active infection
2. Foul odor
3. Purulent drainage
4. Necrotic tissue
5. When autolytic debridement is needed

Scientific Rationale for the Change

Potential Disadvantages of Routine Iodine Use

• Traditional agents like povidone-iodine can be more tissue toxic than their common usage would indicate 2
• Antiseptic agents show no benefit over simple irrigation for clean wounds 3
• No evidence that antimicrobial dressings improve healing outcomes in non-infected wounds 1

Benefits of Saline Cleansing

• Normal saline is isotonic and does not interfere with the normal healing process 4
• Saline is cost-effective and readily available 5
• Clean water or saline is sufficient for regular wound cleansing 1, 4

Modern Approach to Wound Management

Wound Assessment and Cleansing Protocol

1. Assess wound for signs of infection (redness, swelling, increasing pain, purulent drainage, foul odor)
2. For routine, non-infected wounds:
   • Clean with saline or clean water
   • Apply appropriate dressing based on wound characteristics
3. For infected or compromised wounds:
   • Consider antimicrobial agents including iodine products
   • Select based on specific wound characteristics and clinical presentation

Specific Situations for Iodine Use

• When biofilm is present or suspected (iodine can help destroy and inhibit biofilm formation) 1
• For wounds with signs of infection (temperature >38.5°C, heart rate >110 beats/minute, erythema extending >5 cm) 3
• When necrotic tissue is present and requires debridement 1

Evidence on Iodine Efficacy

Despite the shift away from routine use, iodine remains an effective antiseptic when indicated:

• Systematic review evidence shows iodine is an effective antiseptic agent that does not delay wound healing, particularly in chronic and burn wounds 6
• Iodine's antiseptic effect is not inferior to other agents and does not impair wound healing when used appropriately 6

Best Practice Summary

1. For routine wound care: Use saline or clean water for cleansing, and select dressings based on wound characteristics rather than antimicrobial properties
2. For infected or compromised wounds: Consider appropriate antimicrobial agents including iodine-based products
3. For debridement needs: Sharp debridement is preferred when possible, but antimicrobial agents including iodine may be appropriate for autolytic debridement 1

This evidence-based approach ensures that wound care is targeted and appropriate, avoiding unnecessary use of antimicrobial agents while ensuring they are available when clinically indicated.