Integumentary System Presentation PDF

10/21/2023 Integumentary System Burn Introduction 1 1  10/21/2023 Functions of the Integumentary System A. Protection  Chemical Barrier  Physical Barrier  Bi...

10/21/2023 Integumentary System Burn Introduction 1 1  10/21/2023 Functions of the Integumentary System A. Protection  Chemical Barrier  Physical Barrier  Biological Barrier B. Body Temperature Regulation  The body rids itself of excess heat through the skin.  If body temperature rises (external environment hot), blood vessels dilate causing the sweat glands to release sweat.  If body temperature lowers (external temperature cold) the blood vessels constrict to prevent heat loss. 2 2  10/21/2023 Functions of the Integumentary System C. Sensory perception D. Excretion (oil and electrolytes). E. Vitamin D synthesis. F. Cosmetic appearance and identity. G. Metabolic Function H. Blood Reservoir In burn injury, – some or all of these functions may be impaired and/or lost. 3 3  10/21/2023 ANATOMY and PHYSIOLOGY of THE SKIN 4 4  10/21/2023 Skin The skin is the largest organ of the body, comprising approximately 15 percent of body weight(surface area of between 1.5–2.0 m2) Skin is the elastic, self-generating, waterproof covering the body. The skin consists of two distinct layers of tissue: Epidermis – Which is the outermost and has the squamous epithelial tissue Dermis – Which is the deeper layer and consist of reticular connective tissue Hypodermis (The subcutaneous) – layer directly under the dermis and above muscle fascial layers which has the adipose connective tissue (fat cell). 5 5  10/21/2023 The epidermis  The epidermis is the outer layer which is composed of Keratinized stratified squamous epithelium  A tough outer barrier of dead cells  The epidermis is not vascularized  Nutrients are diffused from the dermal layer.  The epidermis has extensive innervation  Types of cells  Keratinocytes  Melanocytes  Merkel cells  Langerhans’ cells 6 6  10/21/2023 The epidermis The thickness of the epidermis (0.07 - 0.12 mm)varies depending on the area. Thickest palmar and planter surfaces (0.8 -1.4 mm). Layers of the Epidermis I. Stratum Corneum II. Stratum Lucidum III. Stratum Granulosum IV. Stratum Spinosum V. Stratum Basale 7 7  10/21/2023 The Epidermis Layers  Stratum corneum This layer consists of fully mature keratinocytes which contain fibrous proteins (keratins). The outermost layer is continuously shed. The stratum corneum prevents the entry of most foreign substances as well as the loss of fluid from the body.  Stratum lucidum- This layer, just beneath the stratum corneum, contains living keratinocytes (squamous cells), which mature and form the stratum corneum. found in thick skin only. 8 8  10/21/2023 The Epidermis Layers  Stratum granulosum is the layer responsible for water retention and heat regulation.  Stratum spinosum adds a layer of protection to the underlying stratum basale layer.  Stratum basal : Basal cells continually divide, forming new keratinocytes, replacing the old ones that are shed from the skin's surface. This layer also contains melanocytes, which determine the coloration of the epidermis. 9 9  10/21/2023 Rete Peg Region Is the interface between the epidermis and the dermis. This area consists of an extensive series of epidermal-dermal ridges and valleys that serve to – increase the surface area between the epidermis and the dermis. – act as a reservoir of skin and are needed to overcome friction. Lack of these ridges in the healed burn wound will result in blisters from abrasion and poor adherence of the new epidermal tissue when it comes in contact with clothing or other surfaces. 10 10  10/21/2023 The dermis The dermis is 20 to 30 times thicker than the epidermis. The dermis is considered the “true skin,” because it contains blood vessels, lymphatics, nerves, collagen, elastic fibers, sweat and sebaceous glands, and hair folliclese of epidermal cells. It is composed of interwoven collagen and elastic fibers, which provide the skin with its tensile strength and elasticity to resist deformation. 11 11  10/21/2023 Dermis layers  The dermis can be subdivided into two layers:  Papillary layer (superficial)  Project upward and interdigitate with the epidermis.  Contain vascular plexuses to nourish the epidermis through osmosis.  Composed of a loose basket-weave network of collagen fibers.  Reticular layer (deep).  The reticular dermis lies below the papillary dermis  Composed of densely interwoven collagen fibers. 12 12  10/21/2023 Structure Location Function Free nerve ending Epidermis Pain, itch Free nerve ending Dermis Pain Merke1’s disks Stratum spinosum Touch Meissner’s corpuscle Papillary dermis Touch Ruffini’s corpuscle Papillary dermis Warm Krause’s end bulb Papillary dermis Cold Pacinian corpuscle Reticular dermis Pressure, vibration 13 13