Lecture 8: Infection 3&4

Lecture 8: Infection 3&4 Cough Reflex · noxious stimulus in upper airways stimulates the cough reflex of medulla ↳ protective reflex ↳ opioids suppress the cough reflex because they depress the CNS eg. codeine Common Cold · viral infection of upper respiratory tract ↳ rhinovirus, RSV, coronaviruses... · signs & symptoms: nasal congestion (coryza), post nasal drip (PND), pharyngitis, headache, malaise ↳ otitis media maybe present · contagious, but self-limiting (10 days) · transmission: airborne (droplet), contaminated surfaces Otitis Media Differences Cold Treatment · Adrenergic Agonists: decreases nasal secretions (vasoconstriction)→aka decongestants ↳ pseudoephedrine & ephedrine · Antihistamines: decreases inflammation symptoms ↳ diphenhydramine ↳ chlorpherinamine ↳ Ioratadine (claritin) · Antitussives: Cough suppression b/c CNS depression ↳ codeine ↳ dextromethorphan · Analgesics: decreases pain ↳ tylenol ↳ menthol · Combination drugs ↳ benylin, triaminic, sudafed optonds en OTHER: · Vitamin C - immunogenic vitamin · Menthol - Vasodilation, cooling, calming · Echinacea - immune modulator; enhances phagocytosis · Ginseng - immune modulator; anti-inflammatory eg. ColdFX Coronavirus · causes the common cold · signs & symptoms: cough, fever, malaise, SOB, headache, rash... · can cause severe multi-organ disease in immunocompromised ↳ massive inflammation and massive vasodilation from noxious stimulus leads to organ failure (not enough perfusion or CO) · can trigger long-term immune response that causes chronic inflammation + chronic fatigue ↳ acute systemic inflammatory response to pathogen = Sepsis · transmission: airborne, droplet, contaminated surfaces · treatment: supportive (prevention w/immunizations) Rhinosinusitis (aka sinusitis) · rhinitis = inflammation of nasal passages · sinusitis = inflammation of sinuses (painful) ↳ frontal, sphenoid, ethmoid, maxillary ↳ have openings "ostia" into nasal cavity ↳ lined with respiratory epithelium → harbours certain bacterium · etiology: Nasal passage inflammation obstructs normal sinus outflow and traps pathogens (nasal congestion) · treatment: empiric therapy (broad) Epiglottitis · sudden and severe inflammation of supraglottic & pharyngeal areas · life threatening b/c of respiratory obstruction · signs & symptoms: mouth breathing, drooling, fever, pale, cyanosis, anxiety, tachycardia · bacterial: Hib, S. pneumoniae, GAS · immediate treatment: empiric antibiotics, ET tube? Influenza · contagious viral infection, fatal in immunocompromised · virus family: orthomyxoviridae ↳ Types A, B, C (A and B most dominant) ↳ subtypes NA, HA - H1N1 (swine flu), H5N1 (bird flu) · causes upper or lower respiratory infections (or both) · viral mechanism of action decreases innate immunity ↳ destroys mucosa ↳ destroys alveoli ↳ allows for opportunistic infections · signs & symptoms: profound malaise, common cold symptomology, fever etc. · complications: sinusitis, otitis media, pneumonia, bronchitis · treatment: ↳ supportive drugs: antipyretics, analgesics, decongestants, antitussives ↳ antivirals eg. oseltamivir (Tamiflu), zanamivir (Ralenza) - better for prophylaxis, only shortens duration ↳ hydration, O2, vaccinations, handwashing Pneumonia · can be community-acquired or nosocomial · Bacterial, viral, or complex (aspiration) ① Bacterial ↳ "typical" pneumonia ↳ more common, more serious ② Viral ↳ "atypical" pneumonia ↳ eg. influenza, RSV · inflammation of bronchioles + alveoli with exudate (pus) · diagnosis: X-ray · signs & symptoms: wet cough, fever, malaise · treatment: according to pathogen (bacterial vs. viral) or empiric ↳ make sure to assess O2 saturation Note consolidation Aspiration Pneumonia · complex pneumonia · usually right middle lobe · at risk: weak host, post-anesthetic, antitussives, positioning of patient Cyanosis ① Peripheral cyanosis ↳ low oxygen, O2 Sat <92% ↳ Upper & lower extremities ↳ maybe normal? (cold) ② Central cyanosis ↳ low oxygen, O2 sat <85% ↳ mucosa, mouth, other body parts ↳ NEVER normal · causes: low oxygenation, low perfusion - Tuberculosis "Consumption" · bacterial pathogen → mycobacterium tuberculosis · contagious · signs & symptoms: malaise, cough, anorexia, fever, coughing · transmission: airborne → spreads by inhalation · aerobic, outer waxy shell (hard to penetrate) · forms granulomas (foci) ↳ latent TB can hide in the foci · diagnosis: X-ray! and sputum, TB skin test · treatment: 6-12 months synergy with ↳ isonazid (INH)(cell wall synthesis inhibitor) ↳ rifampin (DNA inhibitor) ↳ + more anti-TB meds - * Foci (holes)