Integumentary System and Wound Healing

Electrical Stimulation for Wound Healing & Edema

• Electrical stimulation (ES) has shown beneficial effects on different phases of cutaneous wound healing in both chronic and acute wounds, including pressure ulcers, venous ulcers, arterial ulcers, and diabetic foot wounds.
• ES can reduce infection, improve cellular immunity, and increase perfusion, accelerating cutaneous wound healing

Integumentary System

• The integumentary system includes skin, hair, oil and sweat glands, nails, and sensory receptors.
• Functions of the skin include regulating body temperature, storing blood, protecting the body from the external environment, detecting cutaneous sensations, excreting and absorbing substances, and synthesizing vitamin D.

Skin

• The skin is the largest organ of the body and comprises approximately 15% of total body weight.
• The skin has two main layers: the epidermis and the dermis.
• Below the dermis is the subcutaneous tissue or hypodermis.

Epidermis

• The epidermis is the outermost layer of the skin.
• It is composed of keratinized stratified squamous epithelium, a superficial layer without blood vessels.
• It has multiple layers, including the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale, each with distinct characteristics and functionalities.

Dermis

• The dermis is the layer below the epidermis.
• It contains blood vessels, lymphatics, nerves, collagen, and elastic fibers.
• It encloses the epidermal appendages (e.g., hair follicles, sebaceous and sweat glands) and nerves.
• The dermis is primarily composed of interwoven collagen and elastic fibers contributing to its tensile strength and elasticity.
• There are two layers within the dermis; the papillary layer and the reticular layer.

Subcutaneous Tissue (Hypodermis)

• The hypodermis lies beneath the dermis.
• It's mainly composed of fibroblasts, adipocytes, and macrophages.
• The hypodermis is used to estimate total body fat by measuring skin thickness at various locations.

Phases of Wound Healing

• Wound healing has three main phases: inflammation, proliferation, and maturation.
• The inflammation phase involves the body's normal immune response to the injury.
• The proliferation phase is characterized by new tissue formation.
• The maturation phase involves remodeling of new tissue.

Electrical Stimulation Contraindications

• Contraindications for electrical stimulation include a demand cardiac pacemaker, over the carotid sinus, areas of venous/arterial thrombosis or thrombophlebitis, cancer, osteomyelitis under the wound, and over a pregnant uterus.

Electrical Stimulation Precautions

• Precautions for using electrical stimulation include existing cardiac disease, impaired mentation, areas with impaired sensation, areas of skin irritation, and infection control.

Infection Control (Electrical Stimulation)

• Electrodes used in wound treatments should be single-use only.
• Protective covers for ES devices/leads should be used for wound sites, especially for those with chronic or open wounds.

Electrical Stimulation Mechanisms

• Undamaged skin has an endogenous electrical potential and transcutaneous current potential (10-60 mV).
• The movement of sodium ions via Na+/K+ ATPase pumps in the epidermis creates this potential.
• Injury to the skin creates a current flow through the wound termed the "current of injury" or "skin battery" effect.

Electrical Stimulation Types

• Types of electrical stimulation include AC (alternating current), DC (direct current), pulsed current (PC), and degenerate wave (DW).
• Pulsed current can be monophasic or biphasic and is applied to wound tissues through conductive coupling with a hydrogel or moist gauze.

Low Voltage PC (LVPC)

• WoundEL® is an ES wound management system specifically designed for hard-to-heal chronic wounds, to kick-start and accelerate wound healing, and reduce pain.

High Voltage PC (HVPC)

• HVPC uses monophasic pulsed current delivered in doubles, having both positive and negative electrodes.

Direct Current

• Direct current mimics the physiological endogenous current with low-intensity (20-1000 microamps) to avoid damaging healthy tissue and promote wound healing via galvanotaxis (which stimulates the migration of fibroblasts and keratinocytes along an electrical gradient) and antimicrobial effect.

Transcutaneous Electrical Nerve Stimulation (TENS)

• TENS (AC) aside from its analgesic effects, can alter skin temperature and increase blood flow.

Frequency Rhythmic Electrical Modulation System (FREMS)

• This system uses transcutaneous electrotherapy with automatic variation of the pulse, frequency, duration, and voltage.

Biofeedback ES

• Biofeedback ES uses a Fenzian system with degenerate waves to treat symptoms of keloids and hypertrophic scars and to accelerate wound healing in the skin.

Bioelectric Dressings

• Procellera® is a woven metallic bandage with embedded microbatteries used as a dressing for partial or full thickness wounds; delivers ES to the wound site; produces a low voltage (2–10 mV) via silver and zinc microbatteries activated by moisture; delivers 0.6–0.7 V at 10 microamps.

ES for Wound Healing

• ES has shown significant improvement in reducing wound area and accelerating healing, alongside being safe, relatively cost effective and easy to use.

ES for Edema Control

• Edema is a response to tissue trauma, marked by increased pain, diminished function, and prolonged recovery.
• ES is used to manage edema due to inflammation (with HVPC using negative polarity for 30 min, four sessions 4 hrs apart).
• ES can also treat edema from lack of movement (with motor-level electrical stimulation and elevation + compression garments).

Important Note: This document is for educational purposes only and does not constitute medical advice. Always consult with a healthcare professional for personalized guidance and treatment plans.

Explore the intricate functions of the integumentary system, including the role of electrical stimulation in wound healing and edema management. Understand the structure of the skin, its layers, and how they contribute to overall health and healing processes.