176 Week 9 Day 2 Notes Infection/Tissue Integrity

Skin as the Largest Organ

• The skin is the body's largest organ, acting as a barrier.
• It keeps outside elements out and inside elements in.
• Composed of the dermis and epidermis layers.
• Subcutaneous tissue contains fat, used for subcutaneous injections.
• Mucous membranes are also barriers but are more vulnerable. Some have mucus to flush out bacteria.

Body Defenses Against Infection

• The body has various defenses against infection.
• Nursing assistants can apply over-the-counter lotion on intact skin and assist with turning patients and giving blankets.
• They cannot cover a draining wound with treatments or assess it but can contain the drainage to notify the nurse.
• They cannot assess itching rashes but can observe and report to the nurse.

Infection and the Iceberg Concept

• Infection occurs when bacteria invade tissue and multiply.
• The iceberg concept illustrates infection distribution:
  • Most of the iceberg (underwater): asymptomatic carriers. (e.g., people with COVID who had no symptoms but could spread it.)
  • Middle portion (above water): infected but not severely ill (e.g., flu patients who rest and recover at home).
  • Tip of the iceberg: people with classical, severe symptoms of the disease.

Normal Flora and MRSA

• The body is covered in bacteria and fungi, part of our normal flora.
• Example: Healthcare workers often carry MRSA in their noses, kept under control by the immune system.

Infection Control and Handwashing

• Alcohol-based hand sanitizer is less effective on visibly soiled hands.
• Soap and water should be used to remove stickiness from sanitizer residue.
• Certain infections like C. Diff are not killed by alcohol; mechanical washing with soap and water is necessary to remove spores.

Oral Thrush (Candidiasis)

• White patches on mucous membranes that, when swabbed, reveal raw skin underneath are likely thrush.
• Characterized by a white overcast; when swabbed off, the underlying tissue is red and raw.
• Common in babies, people on high doses of antibiotics, and immunocompromised individuals.
• Thrush in a healthy adult indicates an underlying issue.

Chain of Infection

• The key to infection control is breaking the chain of infection.
• Examples of interrupting the chain:
  • Portal of exit: use masks for coughing/sneezing patients.
  • Port of entry: use masks for susceptible individuals.
  • Reservoirs include door handles, stagnant water, and healthcare equipment.
• Portals of exit: urine, feces, saliva, blood, skin, GI tract.
• Portals of entry: broken skin, sexual contact, mouth, respiratory tract, GI tract, contaminated food/water.

Viral Disorders of the Skin: Herpes Simplex and Herpes Zoster

Herpes Simplex

• Two types: type 1 (oral) and type 2 (genital), though either can occur in either location.
• Many people are exposed to type 1, often in childhood.
• Diagnosis can be made by swabbing a lesion.
• Symptoms start with pain, itching, burning, or tingling, followed by fluid-filled vesicles that rupture and crust over.
• The virus remains in the body, with outbreaks triggered by immune system compromise.
• Initial outbreaks are typically the worst.
• Type 1 is usually transmitted through oral secretions; type 2 through sexual contact.
• Cold sores/fever blisters are common manifestations.
• In newborns, herpes simplex can be severe; hence, advising against kissing babies with cold sores.
• Treatment aims to shorten outbreaks and reduce misery, starting within 1-2 days of outbreak.
• Antiviral drugs (suffix: "-cyclovir") are used.
  • Example: acyclovir.
• Over-the-counter treatment: Abreva.
• Severe cases may require PO, topical, or IV acyclovir.
• Frequent outbreaks may warrant daily suppressive therapy with Valtrex (valacyclovir), taken daily to prevent outbreaks.

Herpes Zoster (Shingles)

• Caused by the same virus as chickenpox (varicella zoster).
• Occurs when the virus, dormant in a nerve, reactivates due to immune system suppression.
• Individuals who have not had chickenpox or the vaccine can contract chickenpox from someone with shingles.
• Risk factors include immunosuppressive therapy, chemotherapy, being young or old, stress, and age over 50.
• Complications include postherpetic neuralgia (persistent nerve pain), trigeminal herpes zoster (affecting facial nerves and potentially causing hearing loss), and ophthalmic involvement (affecting the eyes).
• Symptoms: pain/tingling followed by a rash, typically unilateral and following a nerve tract.
• Infectious while the rash is moist (7-10 days).
• Diagnosis: clinical assessment or Tzanck test (swab fluid from blister).
• Management: shorten duration and reduce misery using antivirals (acyclovir, famciclovir, valacyclovir).
• Start treatment within three days of outbreak.
• Burrow's solution (aluminum acetate) can be used as a compress to loosen crusts and soothe skin.
• Pain control: gabapentin (for nerve pain), topical pain relief, corticosteroids (inflammation and itching).
• Vaccine: Shingrix, recommended for adults 50+ and those 19+ with weakened immune systems.
• Capsaicin cream may be used for pain (educate patients on handwashing).
• Isolation: standard precautions if localized and covered with a working immune system; airborne contact if weakened immune system or disseminated rash.

Postherpetic Neuralgia and Other Complications

• Can cause long-term pain, eye complications, encephalitis, trigeminal neuralgia, and facial nerve problems.
• Treatments include analgesics, anticonvulsants (gabapentin), antidepressants, anti-inflammatories, anesthetics, TENS units, nerve blocks, and acupuncture.

General Bacterial Disorders of the Skin: Cellulitis

• Gram-positive bacteria can produce exotoxins; gram-negative bacteria (like C. Diff) produce endotoxins.
• Cellulitis is a common infection affecting the epidermis, dermis, and subcutaneous layers (especially in diabetics).
• Caused by Streptococcus or Staphylococcus aureus, often via skin wounds or ulcers.
• Commonly located in lower extremities, associated with chronic venous insufficiency and stasis dermatitis.
• Bacteria create enzymes causing severe inflammation, resulting in diffuse borders, warmth, sensitivity, redness, and swelling.
• Systemic symptoms: fever, malaise, and chills.
• Erysipelas is a type of cellulitis primarily affecting the dermis and epidermis, caused by Group A Streptococcus.
• Presents as firm red spots merging into defined, bright red, hot lesions with a raised border; vesicles may develop.
• Symptoms: itching, burning, and tenderness.
• Common on the face and lower extremities, especially in infants, young children, older adults, and immunocompromised individuals.
• Other types: orbital cellulitis (around the eye) and necrotizing cellulitis (rare, life-threatening).
• Necrotizing cellulitis risk factors: immunocompromised, diabetic, peripheral artery disease; can lead to sepsis, shock, and organ failure.
• Treatment: moist heat, immobilization, elevation, and systemic antibiotics (culture before administration).
• Nursing interventions: promote rest, warm compresses, antibacterial dressings, ointments, or gels.
• Complications: gangrene and sepsis (can be fatal).
• Symptoms of cellulitis: redness, warmth, swelling, and pain.
• Risk factors: poor hygiene and Diabetes.
• Treatment: antibiotics (penicillin, cephalexin, rifampin, or vancomycin).
• Always use warm compresses to increase blood flow.
• Obtain a culture before administering antibiotics unless it delays care.

Buggies: Lice (Pediculosis) and Scabies

Lice (Pediculosis)

• Medical term for lice: pediculosis.
• Human lice are species-specific and require contact for transmission (they don't fly or jump).
• Adults can survive 48 hours without blood.
• Nits (eggs) take 7-10 days to hatch, with 2 more days for the nymph to mature into an adult.
• Items that cannot be treated should be sealed in plastic for 14 days.
• Three types: pediculosis capitis (head lice), pediculosis corporis (body lice), and pediculosis pubis (pubic lice).
• Easier to spot in dark hair.
• Nits are glued to the hair shaft.
• Adults are hard to see because they run.
• Check around the ears and nape of the neck.
• Treatment: permethrin cream rinse (over-the-counter or prescription).
  • Apply after washing hair, comb through, leave on for 10 minutes, then rinse.
• Nitpicking: use a nit comb daily.
• For infants and pregnant women, use occlusive agents like petroleum jelly.
• Identify and assess family members.
• Educate on how to eliminate lice: use nit combs, discard or soak hair products in boiling water, wash clothing and linens in hot water and dry on high heat, and seal non-washable items in plastic for two weeks.

Scabies

• Microscopic human itch mite that burrows into the skin to live and lay eggs.
• Transmitted person-to-person or via infected sheets/clothing.
• Adult mites can live on objects for two days.
• Incubation: eggs hatch in 3-5 days, adults live for 4-5 weeks.
• Diagnosis: skin scrapings examined under a microscope.
• Mites prefer warm areas with good blood supply and protection, such as between fingers and skin folds.
• May see wavy, brown, thread-like lines (burrows).
• Itching is worse at night.
• Treatment: permethrin cream applied to cool, dry skin at least 30 minutes after bathing.
  • Massage thoroughly onto all skin surfaces from head to soles of feet (avoiding the eyes), leave on for 8-14 hours, then rinse.
• Teach frequent handwashing, keep nails short and clean, and treat family members.
• Wash everything in hot water and dry on high heat.
• Vacuum bags of chairs and sofas, and remove the vacuum contents from the house.

Fungal Infections of the Skin

• Fungi can be single-celled yeasts or colonies of molds or mushrooms.
• Fungi that cause disease are called fungi imperfecti.
• Most healthy individuals' immune systems eliminate fungus.
• Some fungi can be fatal to immunosuppressed individuals.
• Examples: ringworm, athlete's foot, jock itch.
• Superficial infection of the skin; fungus feeds on dead skin cells, preferring warm, moist, dark areas.
• Spread by direct contact or surfaces.
• Candidiasis (yeast infection) is common with antibiotic use.
• Risk factors: diabetes, immunosuppressive therapy, pregnancy.
• Commonly seen in the mouth, vagina, or skin; watch ostomy sites.
• Tinea corporis (ringworm on the body): ring-shaped rash with a smooth center.
• Tinea pedis (athlete's foot): macerated, moist skin with fissures, vesicles, and cracks; may itch, burn, and discolor.
• Treatment: topical (Lotrimin, nystatin, miconazole) or oral antifungals.
• Requires consistent treatment for the full duration (2-6 weeks) to eliminate effectively.
• Tinea corporis treatment: athletes should shower after practice and avoid sharing equipment.
• Key to preventing and treating tinea pedis is airflow and keeping feet dry.

Skin Cancers: Nonmelanomas and Melanoma

• Abnormal nevi is typical and common.
• Nonmelanomas: basal cell carcinoma (pearly or waxy appearance) and squamous cell carcinoma (crusty and scaly).
• Melanoma: the most dangerous. It can appear anywhere (not just sun-exposed areas).
• Risk factors: sun exposure, lack of pigment (pale skin, freckles, light hair/eyes), male gender, smoking, drinking, tanning beds with sunburns.

Basal Cell Carcinoma

• Most common skin cancer.
• Slow-growing, rarely metastasizes.
• Causes tissue damage.
• Treated with Mohs micrographic excision (surgeon removes lesion, microbiologist examines edges to ensure all cancer cells are removed).

Squamous Cell Carcinoma

• Ulcerated, scaly appearance.
• Associated with smoking and alcohol use.
• Grows fast and is metastatic.
• Treated aggressively with Mohs micrographic excision.

Treatments for Both

• Surgical excision.
• Cryotherapy (freezing).
• Radiation therapy.
• Injected drugs.