Respiratory System Lecture Flashcards

Structure and Physiology of the Respiratory System

• Upper Airway Components: Composed of the nose, mouth, pharynx, and trachea.

• Trachea and Bronchial Tree: The trachea divides into the right and left main stem bronchi. The right primary bronchus is a major airway leading to the right lung.

• Lung Anatomy:     - Left Lung: Contains $2$ lobes.     - Right Lung: Contains $3$ lobes.     - Hierarchy of Airways: In each lobe, bronchi divide into secondary (lobar) bronchi and then tertiary (segmental) bronchi. These further divide into bronchioles.

• Alveoli: The bronchioles conclude in the alveoli, which are the functional units of air exchange. Alveoli are lined with mucous membranes.

• Vascular Components: Includes the pulmonary artery (carrying deoxygenated blood to lungs) and pulmonary vein (carrying oxygenated blood to the heart).

• Mechanism of Breathing (Diaphragm): Located beneath the lungs.     - Inspiration: Contraction of the diaphragm enlarges the thoracic cavity.     - Expiration: Relaxation of the diaphragm causes the thoracic cavity to become smaller.

Oxygenation and Ventilation Impairments

• Hypoxemia: Defined as a decreased amount of oxygen ($O_2$) in the blood.

• Hypoxia: Decreased oxygen at the cellular level, often resulting from hypoxemia.

• Hypercapnia: Increased levels of carbon dioxide ($CO_2$) in the blood.

• Onset: May be rapid and obvious or insidious and gradual.

• Causes of Hypoxia:     - Obstruction of the airway.     - Restriction of the thoracic cage.     - Decreased neuromuscular function.

• Signs of Oxygen Deprivation: Symptoms include restlessness, yawning, anxiety, and drowsiness.

Respiratory Assessment and Diagnostic Testing

• Physical Assessment Parameters:     - Respirations: Rate, depth, regularity, effort (labored), and the use of accessory muscles.     - Cough: Frequency, productivity (productive vs. non-productive/moist, dry, hacking).     - Sputum Analysis: Color, consistency, amount, and odor.     - Nasal Discharge: Presence and characteristics.     - Shortness of Breath (SOB): Assessed with or without exertion, precipitating factors, and patient positioning.     - Skin/Mucous Membranes: Color, temperature, and presence of diaphoresis.     - History: Past illnesses, injuries, smoking history, and the number of pillows used for sleep (orthopnea indicator).

• Diagnostic Tests:     - Lung scan and Pulmonary Function Tests (PFTs).     - Bronchoscopy (often abbreviated as Bronch with ca in context of cancer).     - Throat culture and sputum specimens.     - Nasal Cavity inspection and Laryngoscopy.     - CT scans and Sinus X-rays.

Clinical Lung Sounds

• Clear: Normal lung sounds without adventitious noises.

• Rales/Crackles: Discontinuous bubbling or popping sounds similar to Velcro being pulled apart. Usually heard on inhalation; categorized as coarse, fine, moist, or dry. Fine rales/crackles are notably not cleared by coughing.

• Rhonchi (Coarse): Continuous, lower-pitched, coarse rattling sounds heard on both inspiration and expiration. Often caused by loud, bubbly mucus or blockages in the upper airway.

• Wheezes: Musical, whistle-like sounds. Usually high-pitched and expiratory (though can be inspiratory). Caused by narrowed airways associated with Asthma and COPD.

• Stridor: A continuous, high-pitched, musical wheezing sound caused by disrupted airflow. Primarily inspiratory but can be expiratory. Common causes include Croup, infection, or foreign object obstruction.

• Kussmaul: Specific deep, labored breathing pattern mentioned in association with breath sound assessments.

Upper Respiratory Disorders and Pathogens

• Common Pathogens by Condition:     - Sinusitis: $S. pneumoniae$, $H. influenzae$, and $M. catarrhalis$.     - Pharyngitis: $S. pyogenes$, Rhinovirus, Coronavirus, Adenovirus, Influenza virus, Parainfluenza virus, Human metapneumovirus, Respiratory syncytial virus (RSV), Coxsackie virus, and Human bocavirus.     - Nasopharyngitis: Rhinovirus, Coronavirus, Adenovirus, Influenza virus, and Parainfluenza virus.     - Tonsillitis: $S. pyogenes$, $S. pneumoniae$, $H. influenzae$, and $S. aureus$.     - Laryngitis: Parainfluenza virus $1-2$, $H. influenzae$, $M. catarrhalis$, $S. aureus$, Group A and G streptococci, $C. pneumoniae$, and $M. pneumoniae$.

• Sinusitis:     - Definition: Inflammation of the sinuses, typically the maxillary and frontal sinuses.     - Signs/Symptoms: Headache, pain, fullness over sinuses. Chronic cases involve facial/dental pain and nasal congestion.     - Complications: Meningitis, Brain abscess, and Osteomyelitis.     - Treatment: Decongestants, steam, fluids, and antibiotics.

• Allergic Rhinitis (Hay Fever):     - Types: Acute (seasonal) or Chronic (perennial).     - Signs/Symptoms: Itchy watery eyes, sneezing, clear nasal drainage, and frontal headache.     - Treatment: Antihistamines and saline sprays.     - Allergy Shots: Works like a vaccine to reduce allergic antibodies. Starts with a small dosage building over time. Given $1-2$ times a week for $3-6$ months until constant, then monthly for $3-5$ years. Effects last $5-10$ years after cessation.

• Common Cold (Coryza):     - Nature: Viral inflammation of the upper respiratory system; spread by droplets.     - Signs/Symptoms: Nasal secretions, postnasal drip, sore throat, fever, headache, coughing, and sneezing.     - Resolution: Usually resolves in $2-10$ days.     - Treatment: Symptomatic care (analgesics, antipyretics, cough suppressants, expectorants), fluids, and rest.

• Deviated Septum:     - Definition: Septum is off-center.     - Signs/Symptoms: Headache, congestion, sinusitis, and epistaxis (nosebleed).     - Treatment: Surgical correction via Submucosal resection or Submucosal nasal septoplasty.

• Epistaxis (Nosebleed):     - Causes: Trauma, clotting disorders, dryness, inflammation, and hypertension.     - Treatment: First aid, nasal packing, or nasal balloon catheters.

Throat Conditions and Surgical Interventions

• Pharyngitis:     - Definition: Inflammation of the throat mucus membranes. Can be viral, bacterial (Strep throat), or fungal.     - Signs/Symptoms: Dryness, pain, dysphagia (difficulty swallowing), fever, and reddened, enlarged tonsils.

• Tonsillitis:     - Definition: Acute inflammation of tonsils, common in school-age children.     - Signs/Symptoms: Sore throat, fever, chills, anorexia, enlarged/tender lymph nodes, and muscle aches.     - Surgical Management (Tonsillectomy):         - Indicated for chronic recurrent tonsillitis.         - Post-Op Monitoring: Hemorrhage is the most serious complication. Observe for excessive swallowing.         - Post-Op Care: Use ice collars; avoid clearing the throat, coughing, sneezing, or blowing the nose for $2$ weeks.         - Diet: Clear cold liquids first. Avoid Red, Brown, or Purple fluids/foods (to avoid confusion with blood). Advance to soft, then regular diet.

• Obstructive Sleep Apnea (OSA):     - Definition: Airway obstruction during sleep due to narrowing.     - Signs/Symptoms: Snoring and persistent fatigue despite full night's sleep.     - Treatment: Weight loss, avoiding sedatives/alcohol, and surgery to reduce obstructing tissue.     - CPAP (Continuous Positive Airway Pressure): Single set pressure throughout sleep.     - BiPAP (BiLevel Positive Airway Pressure): Two distinct pressure settings for inhale and exhale.

• Laryngitis:     - Definition: Inflammation of the voice box (larynx). Can be acute or chronic.     - Causes: Colds, flu, GERD, voice overuse, and irritants (smoke/allergies).     - Signs/Symptoms: Raspy/hoarse voice (or total loss), pain, dysphagia, and dry/sore throat.     - Treatment: Voice rest, humidifiers, fluids, and avoiding irritants.

Cancer of the Larynx

• Overview: Curable with early detection; potential for metastasis.

• Risk Factors: Family history, smoking, alcohol use, chronic laryngitis, and voice overuse.

• Signs/Symptoms: Difficulty swallowing (early sign), dyspnea, burning sensation with hot liquids or juices, and weight loss.

• Treatment Options:     - Chemotherapy and Radiation.     - Laryngectomy (Partial or Complete).     - Radical neck dissection with permanent tracheostomy.

• Post-Operative Care:     - Maintain a patent airway; have suction equipment on hand.     - Semi-Fowler’s position and prevention of head movement.     - Dressing/drain observation.     - Nutrition: Initial tube feeding progressing to ice chips, then previous diet.

• Communication Methods: Use of call bells for prompt answers; communication aids like the Electrolarynx (speech aid) or participation in patient support groups like the Chord Club.