Gilead -Topics in Human Pathophysiology
Fall 2009 Drug Safety and Public Health
Respiratory system and Disease
• Respiratory System structures– Airways– Respiratory interface– Gas transport– Lungs and ventilation
• Selected Respiratory Disorders
Unlabeled Figure 10.1
Figure 10.1
Respiratory Interface
• Alveolar wall• Capillary wall• Surfactant• Gas Exchange occurs by diffusion
Figure 10.8
Gas Transport
• Oxygen
• Carbon dioxide
Figure 10.7
Respiratory Disorders
• H1N1• Asthma• Cystic fibrosis• Pulmonary aspergillosis• Pneumonia
H1N1• Cause
– Influenza A virus• Symptoms
– Fever– Sore throat– Cough– Body aches– Headache– Chills– Fatigue– Vomiting and diarrhea
H1N1
H1N1
• Susceptible populations• Antivirals for influenza – Tamiflu (oseltamivir),
Relenza (zanamivir), peramivir• Complications
– Pneumonia and respiratory failure– Bronchitis– Ear infections– Sinus infections
Asthma
Cystic fibrosis
• Inherited disorder causing a defect in a cell membrane Cl- channel
• Causes thick sticky mucus buildup in airways and ducts of pancreas, etc.
• Shortens lifespan because of pneumonia, malnutrition, etc.
Pulmonary aspergillosis
• Fungal lung infection• Common with AIDs patients and cystic fibrosis
patients• Treated with Ambisome (amphoterocin B),
one of several antifungals, alters fungal cell permeability
Pulmonary Aspergillosisfrom an AIDS patient during autopsy
http://www.ispub.com/ostia/index.php?xmlFilePath=journals/ijid/vol6n1/aspergillosis.xml
Pneumonia
• Fluid buildup in lung alveoli• Thickens respiratory interface, interrupting
diffusion of gases• Caused by a wide variety of microorganisms
including aspergillus and pneumocystis fungi, influenza virus (Tamiflu), cytomegalovirus (Vistide)
Pneumonia
Tests for Lung Function
• Chest X-ray (CXR)• Pulmonary function tests• Sputum cultures• Pulse oximetry• Arterial Blood Gases (ABGs)
Pneumonia X-ray
http://www.med-ed.virginia.edu/courses/rad/cxr/pathology3chest.html
Figure 22.16a
Pulmonary Function Tests
Figure 22.16a
FEV1
Should be at least 80% of
VC
FEV1
Should be at least 80% of
VC
(VC)
Sputum Culture
•Patient donates a sputum sample•It is cultured with various media to determine causative agent of lung infection
Pulse Oximetry
•Measures arterial hemoglobin oxygen saturation•Normal is > 95%•Indicator of effectiveness of respiratory interface and gas diffusion
Arterial Blood Gases
• pH• PCO2
• PO2
• O2 Saturation
• HCO3-