Respiratory System Quiz

Respiratory System

• Obstructive vs. Restrictive Lung Diseases: Obstructive = increased resistance, same volume reached but takes longer, FEV1 decreased, FVC same. Restrictive = decreased compliance, lungs cannot fully expand, lower volume, FVC decreased, FEV1 decreased, FEV1:FVC same or increased.
• Compliance: stretching ability of the lungs, affected by lung tissue thickness.
• Peak Flow Meter: normal range = 500-600L/min.

Respiratory Physiology

• V/Q Ratio: Lack of perfusion (dead space) increases V/Q ratio, lack of ventilation (pulmonary shunt) decreases V/Q ratio.
• Bohr Effect: High CO2 in respiring tissues decreases affinity for O2, more dissociation, more O2 for tissues, curve shifts right.
• Haldane Effect: High O2 in the lungs increases affinity for O2, O2 replaces CO2 on Hb, more O2 taken up by Hb, curve shifts left.

Hypersensitivity Reactions

• Type 1: allergic reaction, IgE, requires previous exposure, within minutes.
• Type 2: IgM + IgG, minutes to hours, autoimmune diseases (e.g., Grave's).
• Type 3: immune complex, IgM + IgG, 2-6 hours, rheumatoid arthritis and lupus, causes oedema and inflammation.
• Type 4: no antibodies involved, 24-48 hours, T cells activate cell-mediated response, tissue damage and inflammation.

Respiratory Diseases

• Asthma: obstructive disease, reversible bronchospasm, symptoms: wheeze, dyspnoea, dry cough, management: SABA, ICS, Leukotriene receptor antagonist.
• COPD: damage to bronchi and alveoli, chronic bronchitis and emphysema, symptoms: barrel chest, brown mucus, SOB, wheeze, peripheral oedema, management: bronchodilator or LABA/LAMA.
• Pneumonia: infection of the lungs, symptoms: productive cough, fever, chest pain, SOB, fine crackles, confusion, management: antibiotics, oxygen, and fluids.

Respiratory Failure

• Type 1: hypoxia without hypercapnia.
• Type 2: hypoxia with hypercapnia.

Other Respiratory-Related Topics

• Wheeze: noisy breathing during expiration, caused by bronchoconstriction (e.g., asthma).
• Stridor: noisy breathing during inspiration, caused by insufficient innervation of larynx (e.g., recurrent laryngeal nerve injury).
• Hoarse Voice: recurrent laryngeal nerve injury.
• Cystic Fibrosis: autosomal recessive, diagnosed with heel prick test, symptoms: SOB, cough, wheeze, salty skin, low weight, pneumonia, treatment: potentiator (e.g., Ivacaftor) and corrector (e.g., Lumacaftor).

Inheritance

• Mitochondrial Diseases: 100% inheritance if mother is affected.
• Huntington's Disease: autosomal dominant.
• X-linked Dominant: father affected, all daughters affected, mother affected, 50% of children affected.
• X-linked Recessive: only affects boys, father carrier, all daughters carriers.
• Y-linked: only affects males.

Anatomy

• Little's Area (Kiesselbach's Plexus): most common site for an epistaxis.
• Ostia: communicates with paranasal sinuses.
• Paranasal Sinuses: Sphenoid - roof of posterior nasal cavity.