What is the appropriate treatment for a chemical burn on the sole of the foot, including irrigation, dressing, pain control, tetanus prophylaxis, and criteria for referral?

Treatment of Chemical Burns to the Sole of the Foot

Immediately irrigate the chemical burn with copious running tap water for at least 15 minutes, starting within 3 minutes of exposure if possible, as this single intervention significantly reduces full-thickness burns, hospital length of stay, and long-term complications. 12

Immediate Decontamination (First Priority)

Remove Contaminated Materials First

• Remove shoes, socks, and any jewelry from the affected foot immediately to prevent chemicals from being trapped against the skin during irrigation 12
• For dry chemical powders (such as sodium hydroxide, elemental sodium, or potassium), brush off as much powder as possible before water irrigation to avoid exothermic reactions 12

Water Irrigation Protocol

• Begin copious running tap water irrigation within 3 minutes of exposure and continue for at least 15 minutes minimum 12
• Studies demonstrate that immediate irrigation (within 3 minutes) versus delayed irrigation results in fewer full-thickness burns, shorter hospital stays, and fewer delayed complications 13
• Continue irrigation longer if pain persists or if the specific chemical agent is unknown 2
• Do not delay irrigation to search for neutralizing agents—water should begin immediately 2

Special Chemical Considerations

• Contact your regional poison control center if the specific chemical is known, as certain agents (hydrofluoric acid, phenol) require specialized decontamination beyond water 12
• For most unknown chemical exposures to the foot, tap water remains the appropriate first-line decontamination agent 14

Post-Irrigation Wound Care

Dressing Application

• After completing irrigation, apply a petrolatum-based product or topical antibiotic ointment (such as polymyxin) to keep the wound moist 2
• Cover loosely with a clean, non-adherent dressing to reduce pain, protect from contamination, and limit heat loss 2
• Avoid silver sulfadiazine for superficial chemical burns, as prolonged use is associated with delayed healing 2

Wound Cleaning

• Clean the wound with tap water, isotonic saline, or antiseptic solution before applying the dressing 5

Pain Management

Outpatient Pain Control

• Administer over-the-counter analgesics such as acetaminophen or NSAIDs for pain control in minor burns 5

Severe Burns Requiring Hospitalization

• Employ a multimodal analgesic regimen guided by validated pain-assessment scales 2
• Titrated intravenous ketamine combined with short-acting opioids is effective for managing severe burn pain requiring hospital admission 2

Tetanus Prophylaxis

• Ensure tetanus immunization is current for any chemical burn with broken skin, following standard wound-management protocols (though not explicitly detailed in the chemical burn guidelines, this remains standard burn care)

Criteria for Immediate Referral to Emergency Care or Burn Center

Anatomic Location

• Burns to the feet automatically warrant immediate medical attention and likely referral to specialized care 25

Burn Severity Indicators

• Respiratory symptoms or difficulty breathing after chemical exposure 2
• Partial-thickness burns covering >10% total body surface area in adults (>5% in children) 2
• Any full-thickness (third-degree) burns 2
• Burns with blisters or broken skin 2
• Infected or very painful burns 2

Additional High-Risk Features

• Deep circular burns that may compromise circulation (may require early escharotomy) 2
• Systemic symptoms suggesting chemical absorption 1

Critical Pitfalls to Avoid

• Never apply ice directly to chemical burns, as this causes additional tissue ischemia and damage 25
• Do not apply butter, oil, or other home remedies, as these trap heat and worsen injury 25
• Do not break blisters, as this increases infection risk 25
• Do not delay irrigation to identify the specific chemical—begin water lavage immediately 2
• Do not use saline as a substitute for tap water in initial irrigation, as animal studies show tap water achieves superior pH neutralization 4

Algorithm Summary

1. Immediate action (0-3 minutes): Remove shoes/socks/jewelry → Brush off dry powder if present → Begin tap water irrigation
2. Continue irrigation: Minimum 15 minutes, longer if pain persists
3. Post-irrigation: Apply petrolatum-based ointment → Non-adherent dressing
4. Pain control: Oral analgesics for minor burns
5. Referral decision: Any foot burn with blisters, broken skin, or concerning features → Emergency care/burn center