Pulmonary and Critical Care

Question 2

Uworld Pathology: COPD
What is the formula for the Reid Index?

Answer 2

RI = Mucous glands/ submucosa + lamina propria

Question 3

Biochemistry: Metabolic Acidosis
Explain the underlying mechanism of lactic acidosis caused by seizures or exercise:

Answer 3

Enhanced metabolic rate

Question 4

Biochemistry: Metabolic Acidosis
Explain the underlying mechanism of lactic acidosis caused by Cardiac/Pulmonary failure or tissue ischemia/infarction:

Answer 4

Reduced oxygen delivery

Question 5

Biochemistry: Metabolic Acidosis
Explain the underlying mechanism of lactic acidosis caused by hepatic failure or hypoperfusion (eg. septic shock):

Answer 5

Diminished lactate catabolism in the case of hepatic failure and increase lactic acid from impaired oxidative phosphorylation in hypoperfusion.

Question 6

Biochemistry: Metabolic Acidosis
Explain the underlying mechanism of lactic acidosis caused by Cyanide poisoning:

Answer 6

Decreased oxygen utilization

Question 7

Biochemistry: Metabolic Acidosis
Explain the underlying mechanism of lactic acidosis caused by Glycogen storage disease (von Gierke) or mitochondrial myopathies:

Answer 7

Enzymatic defects

Question 8

Biochemistry: Aspiration Pneumonia
Describe the different predisposing conditions for aspiration pneumonia:

Answer 8

• altered consciousness impairing cough reflex/ glottic closure (eg, dementia, drug intoxication)
• dysphagia due to neurological deficitis (eg, stroke, neurodegenerative disease)
• upper GIT disorders (eg, GERD)
• mechanical compromise of aspiration defenses (eg, nasogastric and endotracheal tubes)
• protracted vomiting
• large volume tube feeding in recumbent position

Question 9

Pathology: Lobar Pneumonia
What are the causative agents of aspiration pneumonia?

Answer 9

• Klebsiella pneumoniae
• anaerobic bacteria such as Bacteroides, Fusobacterium, and Peptostreptococcus species

Question 10

Pathology: Lobar Pneumonia
What are the four stages of lobar pneumonia?

Answer 10

• congestion
• red hepatization
• gray hepatization
• resolution

Question 11

Pathology: Lobar Pneumonia
Describe the stage of Lobar Pneumonia: Congestion

Answer 11

• occurs during the first 1-2 days of infection
• resembles an active infection showing an influx of inflammatory cells
• increased permeability and vasodilation gives a red-purple appearance of the lung parenchyma
• alveolar exudate consists mainly of bacteria

Question 12

Pathology: Lobar Pneumonia
Describe the stage of Lobar Pneumonia: Red Hepatization

Answer 12

• occurs 3-4 days after the onset of symptoms
• starts to show signs of consolidation: bronchophony and whispered pectoriloquy
• Red- brown consolidation with exudate consisting of fibrin, bacteria, erythrocytes, and neutrophils

Question 13

Pathology: Lobar Pneumonia
Describe the stage of Lobar Pneumonia: Gray Hepatization

Answer 13

• occurs 5-7 days after symptom onset
• signifies the infective organism started dying
• uniformly gray consolidation with exudate consisting of neutrophils and erythrocytes degradation products
• after 5 days bronchophony points you to this stage of disease progression

Question 14

Pathology: Lobar Pneumonia
Describe the stage of Lobar Pneumonia: Resolution

Answer 14

• occurring at least 8 days after symptom onset
• educate is enigmatically digested by macrophages
• normal lung parenchyma is regenerated by type II pneumocytes