EB

Dermatology, Skin, Eyes, and Ears Review (Fill-in-the-Blank)

Thermoregulation and Post-resuscitation Care

  • Temperature regulation: vasoconstriction/insulation and shivering to heat the body; vasodilation → heat loss (heat exhaustion).
  • ROSC (return of spontaneous circulation) post-arrest is managed with ACLS; targeted cooling (therapeutic hypothermia) to protect the brain, then controlled rewarming.

Skin: Structure, Function, and Color Changes

  • Skin functions: barrier against pathogens; secretion/absorption (sweat excretes uric acid, ammonia, urea); absorbs topical medications; vitamin D production; protective and reflective of internal disease.
  • Color changes indicating systemic states:
    • Cyanosis = hypoxia
    • Pallor = anemia
    • Redness (erythema) = inflammation or flushing
    • Jaundice/Yellow-orange = liver dysfunction or high beta-carotene; orange skin noted with beta-carotene excess
  • Epidemiology:
    • 30\% of Americans have some skin condition
    • 50\% of primary care visits relate to skin issues
  • Skin as a diagnostic mirror: integumentary system reflects internal health; no two skin disorders present exactly the same way.

Skin Assessment and Pathophysiology

  • Key assessment factors: color, texture, turgor (elasticity), moisture, tenderness.
  • Turgor insights: rapid return = good hydration; slow return = dehydration or poor skin elasticity.
  • Intact skin is essential for protection; changes can indicate pathology.

Skin Disorder Classification and Treatment Approaches

  • Classifications: infectious, inflammatory, neoplastic (cancer).
  • Treatments can be oral, parenteral, or topical.

Viral Skin Infections

  • Verrucae (HPV): cauliflower-like warts; treatment includes liquid nitrogen, salicylic acid, keratolytics.
  • Herpes simplex: HSV-1 (oral) and HSV-2 (genital); cluster blisters with prior tingling; treatment with acyclovir; topical for oral, systemic for genital presentations.

Fungal Infections

  • Candida albicans: thrush (mucosal) and intertriginous skin infections; common in immunocompromised or with moisture.
  • Tinea species (dermatophytes): capitis, corporis, cruris, faciei, pedis; treated with azole antifungals.

Bacterial Infections

  • Impetigo: Staph aureus or Streptococcus; honey-colored crust; topical antibiotics (e.g., mupirocin).

Acne and Rosacea

  • Acne vulgaris: comedones (open blackheads, closed whiteheads); hormonal stimulation of sebaceous glands; isotretinoin (Accutane) is effective but teratogenic; caution in young females.
  • Rosacea: vasodilation with erythema and papules/pustules; avoid triggers; treatment targets symptoms (steroids, antihistamines like diphenhydramine).

Other Inflammatory Skin Conditions

  • Psoriasis: silvery scales on erythematous base; psoriatic arthritis risk.
  • Lichen planus: unknown cause; mucosal involvement; treated with steroids.
  • Eczema/Atopic dermatitis: flares at flexural surfaces; moisturizers, topical steroids; stress and temp changes can trigger; avoid irritants.
  • Urticaria (hives) with possible angioedema; histamine release; risk if airway involvement (anaphylaxis); treat underlying trigger; antihistamines; if prolonged >6 weeks consider autoimmune component.
  • Autoimmune: Systemic lupus erythematosus (SLE) with butterfly rash; managed with steroids.

Skin Cancer: Melanoma and Non-melanoma

  • Melanoma: most deadly skin cancer; ABCDEs for detection:
    • Asymmetry
    • Border irregularity
    • Color variation
    • Diameter > 6\text{ mm}
    • Evolving
      Early detection crucial; treatment is complete surgical excision and staging.
  • Basal cell carcinoma (BCC): most common; may be slow-growing; pearly appearance with telangiectasias; rarely metastasizes; treatment includes cryotherapy, topical chemotherapy, biopsy for confirmation.
  • Squamous cell carcinoma (SCC): second most common; nonhealing ulcers or nodules; potential to metastasize; early treatment is curative.

Parasitic and Vector Skin Conditions

  • Scabies: mites burrow under skin (webs of fingers, toes, wrists); intense pruritus; transmission via close contact; treat with scabicides.
  • Pediculosis (lice): head lice; itching; treat with topical pediculicides.
  • Ticks: vectors for Lyme disease, Rocky Mountain spotted fever, encephalitis, tularemia; remove promptly and monitor.

Eczema, Urticaria, and Autoimmune Skin Disorders

  • Eczema (atopic dermatitis): chronic itchy, inflammatory condition; management includes moisturizers, avoidance of triggers, topical steroids.
  • Angioedema and urticaria: swelling and hives; urgent assessment if airway compromise suspected.
  • Autoimmune: SLE and other autoimmune rashes; steroids are a common treatment.

Eyes: Anatomy, Glaucoma, Cataracts, and Retina

  • Aqueous humor dynamics: produced by the ciliary body; flows from the posterior chamber through the pupil to the anterior chamber; exits via the canal of Schlemm; intraocular pressure (IOP) regulated.
  • Normal IOP: 10 \leq \text{IOP} \leq 21\ \text{mmHg}.
  • Glaucoma
    • Primary open-angle glaucoma (POAG): silent, chronic, open angle.
    • Primary angle-closure glaucoma (PACG): acute emergency due to narrowing of the angle; obstruction of drainage increases IOP.
    • Acute glaucoma requires immediate treatment to prevent vision loss.
  • Cataracts: lens opacity; risk factors include age, smoking, obesity, diabetes; congenital causes (rubella, CMV, syphilis).
  • Retinal detachment: emergency; symptoms include sudden floaters, cobwebs, curtain/shadow; treatment: rest and surgical repair; patch both eyes to avoid tracking movement of the healthy eye.
  • Anticholinergic drugs can worsen glaucoma; avoid in patients with glaucoma.

Ears: Hearing Loss and Balance Disorders

  • Hearing loss types: conductive, sensorineural (nerve), and central.
  • Conductive hearing loss: impaired conduction (often due to cerumen impaction or otitis externa).
  • Otitis media: middle ear infection; common in children; causes earache, fever, and fussiness; treatment includes analgesics and sometimes antibiotics; possible tympanotomy for drainage.
  • Otitis externa: swimmer's ear; outer ear inflammation with canal swelling and discharge.
  • Sensorineural (central) hearing loss: damage to inner ear structures or auditory nerve; requires evaluation of the auditory pathway.
  • Tinnitus: ringing or buzzing in the ears; may accompany Meniere's disease.
  • Meniere's disease: episodic vertigo, hearing loss, and tinnitus; managed with diuretics, steroids, and sometimes vestibular therapy or devices.
  • Hallpike maneuver and canalith repositioning: used to treat vertigo from crystal displacement in the inner ear.
  • Ear wax removal: warm water irrigation is preferred; avoid cold water which can provoke nystagmus via vestibular reflexes.
  • Eighth cranial nerve (vestibulocochlear) involvement: balance and hearing pathway; damage affects hearing and balance.