Phys 39 Flashcards

The lung receives blood through which two circulatory systems?

A. Both high-pressure, low-flow

B. High-pressure and low-pressure systems

C. Both low-pressure, high-flow

D. High-flow and lymphatic systems

The bronchial arteries arise primarily from the:

A. Pulmonary trunk

B. Internal thoracic arteries

C. Subclavian arteries

D. Thoracic aorta

Which pulmonary circulation carries systemic venous blood to the alveolar capillaries?

A. Low-pressure, high-flow circulation

B. High-pressure, low-flow circulation

C. Bronchial venous circulation

D. Pulmonary lymphatic circulation

The pulmonary arterial tree normally has:

A. Minimal compliance

B. Variable compliance

C. Large compliance

D. No measurable compliance

Large pulmonary arterial compliance allows accommodation of:

A. Left ventricular end-systolic volume

B. Pulmonary venous reserve volume

C. Right ventricular stroke volume

D. Left atrial residual volume

Pulmonary veins empty directly into the:

A. Left atrium

B. Right atrium

C. Left ventricle

D. Pulmonary artery

Which comparison is correct?

A. Both carry oxygenated blood

B. Both carry deoxygenated blood

C. Bronchial blood is deoxygenated

D. Bronchial blood is oxygenated

Bronchial arteries primarily supply the:

A. Alveolar capillary blood

B. Supporting tissues of lungs

C. Right ventricular myocardium

D. Pulmonary venous valves

After supplying lung tissues, bronchial arterial blood usually drains into:

A. Pulmonary veins

B. Pulmonary arteries

C. Superior vena cava

D. Right atrium

Pulmonary lymphatics primarily help prevent:

A. Pulmonary vasoconstriction

B. Bronchial hemorrhage

C. Pulmonary edema

D. Alveolar hypoxia

During systole, pulmonary arterial pressure approximates pressure in the:

A. Left atrium

B. Right ventricle

C. Left ventricle

D. Pulmonary veins

Normal pulmonary arterial systolic pressure is approximately:

A. 7 mmHg

B. 8 mmHg

C. 15 mmHg

D. 25 mmHg

Normal pulmonary arterial diastolic pressure is approximately:

A. 8 mmHg

B. 15 mmHg

C. 25 mmHg

D. 35 mmHg

Normal mean pulmonary arterial pressure is approximately:

A. 7 mmHg

B. 15 mmHg

C. 25 mmHg

D. 40 mmHg

Normal mean pulmonary capillary pressure is approximately:

A. 2 mmHg

B. 15 mmHg

C. 7 mmHg

D. 25 mmHg

Pulmonary wedge pressure is useful for assessing:

A. Right atrial pressure only

B. Systemic arterial resistance

C. Right ventricular contractility

D. Pulmonary capillary and left atrial pressures

Approximately what percentage of total blood volume is located in the lungs?

A. 3%

B. 9%

C. 15%

D. 25%

Blood may accumulate in the pulmonary circulation due to:

A. Left heart failure or mitral stenosis

B. Right heart failure or aortic stenosis

C. Tricuspid regurgitation or pulmonic stenosis

D. Systemic hypertension or venous dilation

Total blood flow through the lungs is essentially equal to:

A. Coronary blood flow

B. Bronchial blood flow

C. Cerebral blood flow

D. Cardiac output

How do pulmonary and systemic vessels respond to low oxygen?

A. Both constrict

B. Both dilate

C. Pulmonary constricts; systemic dilates

D. Pulmonary dilates; systemic constricts

Nitric oxide produces which vascular effect?

A. Vasodilation

B. Vasoconstriction

C. Capillary closure

D. Venous thrombosis

Increased calcium concentration in small pulmonary arteries and arterioles causes:

A. Vasodilation

B. Increased compliance

C. Vasoconstriction

D. Capillary recruitment

Pulmonary capillaries close when:

A. Capillary pressure exceeds alveolar pressure

B. Alveolar pressure exceeds capillary pressure

C. Venous pressure exceeds arterial pressure

D. Pleural pressure becomes negative

Which pulmonary blood-flow zone pairing is correct?

A. Zone 1 continuous; zone 3 absent

B. Zone 1 absent; zone 3 continuous

C. Zone 1 intermittent; zone 2 continuous

D. Zone 2 absent; zone 3 intermittent

Which pulmonary blood-flow zones normally exist in healthy lungs?

A. Zones 1 and 2

B. Zones 2 and 3

C. Zone 1 and 3

D. Zone 2 and 3

Zone 1 pulmonary blood flow can occur when:

A. Venous pressure becomes excessive

B. Pleural pressure becomes negative

C. Capillary pressure exceeds alveolar pressure

D. Arterial pressure falls or alveolar pressure rises

Increased pulmonary blood flow is accommodated partly by:

A. Closing existing capillaries

B. Reducing venous return

C. Opening additional capillaries

D. Decreasing arterial compliance

Capillary distention can increase flow through each capillary by:

A. More than twofold

B. About one quarter

C. Less than one half

D. Exactly tenfold

A third mechanism accommodating increased pulmonary flow is increased:

A. Left atrial pressure

B. Pulmonary arterial pressure

C. Alveolar air pressure

D. Pleural fluid pressure

In a healthy person, left atrial pressure rarely exceeds:

A. +2 mmHg

B. +10 mmHg

C. +15 mmHg

D. +6 mmHg

During left-sided heart failure, blood initially dams up in the:

A. Left atrium

B. Right atrium

C. Pulmonary artery

D. Right ventricle

Blood flowing through the numerous alveolar capillaries forms a:

A. Sheet of flow

B. Column of flow

C. Turbulent jet

D. Venous reservoir

Blood normally passes through pulmonary capillaries in approximately:

A. 0.2 seconds

B. 1.5 seconds

C. 0.8 seconds

D. 3.0 seconds

Pulmonary and peripheral functional capillary pressures are approximately:

A. 17 and 7 mmHg

B. 15 and 25 mmHg

C. 7 and 17 mmHg

D. 8 and 15 mmHg

Compared with peripheral subcutaneous tissue, pulmonary interstitial pressure is:

A. More positive

B. Slightly more negative

C. Exactly equal

D. Highly variable

Pulmonary interstitial colloid osmotic pressure is approximately:

A. 7 mmHg

B. 17 mmHg

C. Less than 4 mmHg

D. 14 mmHg

Thin alveolar walls may rupture when interstitial pressure becomes:

A. Greater than alveolar air pressure

B. Lower than venous pressure

C. Equal to pleural pressure

D. Lower than arterial pressure

The most common hydrostatic causes of pulmonary edema are:

A. Right failure and tricuspid disease

B. Left failure and mitral disease

C. Aortic disease and hypertension

D. Pulmonic disease and bradycardia

Pulmonary capillary membrane damage may result from:

A. Systemic hypertension only

B. Mitral stenosis

C. Low plasma sodium

D. Pneumonia or toxic gases

Chronically elevated pulmonary capillary pressure increases edema resistance because:

A. Alveolar walls become thicker

B. Capillary pressure decreases

C. Lymphatic vessels expand

D. Plasma proteins increase

Once capillary pressure exceeds the pulmonary safety factor, lethal edema may develop within:

A. Several weeks

B. Several days

C. Several hours

D. Several months

Excess pleural fluid may spread over the:

A. Alveolar ducts and bronchi

B. Pericardium and ventricular walls

C. Mediastinum, diaphragm, parietal pleura

D. Pulmonary arteries and veins

The space between parietal and visceral pleurae is a:

A. Potential space

B. True cavity

C. Vascular sinus

D. Lymphatic duct

Which force must act outside the lungs to maintain expansion?

A. Negative force

B. Positive force

C. Osmotic force

D. Gravitational force

The normal collapse tendency of the lungs is approximately:

A. +4 mmHg

B. −8 mmHg

C. +8 mmHg

D. −4 mmHg

Pleural effusion is most analogous to: A. Alveolar ventilation

B. Tissue edema

C. Arterial congestion

D. Bronchial constriction

Which pair can cause pleural effusion?

A. Hyperventilation and fever

B. Lymphatic blockage and cardiac failure

C. Increased plasma protein and dehydration

D. Bronchodilation and tachycardia

Additional causes of pleural effusion include:

A. Increased plasma oncotic pressure

B. Excessive lymphatic drainage

C. Reduced capillary permeability

D. Low plasma oncotic pressure and inflammation

The high-pressure, low-flow pulmonary circulation supplies which structures?

A. Alveoli and pulmonary capillaries

B. Trachea, bronchi, supporting tissues, adventitia

C. Left atrium and ventricle

D. Pleura and alveoli only

Pulmonary lymph vessels in supporting lung tissues empty mainly into the:

A. Left thoracic duct

B. Pulmonary veins

C. Superior vena cava

D. Right thoracic lymph duct

Alveolar hypoxia promotes pulmonary vasoconstriction partly by:

A. Increasing vasoconstrictor release

B. Increasing nitric oxide release

C. Lowering intracellular calcium

D. Increasing vasodilator release

Alveolar hypoxia may also cause vasoconstriction by decreasing the release of:

A. Vasoconstrictors

B. Catecholamines

C. Vasodilators

D. Plasma proteins

The overall effect of alveolar hypoxia on pulmonary vascular resistance is:

A. No significant change

B. Increased resistance

C. Decreased resistance

D. Complete vascular collapse

Pressure differences caused by the weight of blood are called:

A. Oncotic pressure

B. Alveolar pressure

C. Osmotic pressure

D. Hydrostatic pressure

Which pulmonary blood-flow zones normally occupy the lower lung?

A. Zones 2 and 3

B. Zone 1 only

C. Zones 1 and 2

D. Zone 3 only

Most blood flow in the lower lung occurs under which zone conditions?

A. Zone 1

B. Zone 2

C. Zone 3

D. No defined zone

In zone 2 at the lung apex, blood flows primarily during:

A. Diastole

B. Inspiration

C. Expiration

D. Systole

Zone 1 pulmonary blood flow may develop during:

A. Heavy exercise

B. Severe blood loss

C. Increased cardiac output

D. Normal quiet breathing

During exercise, total pulmonary blood flow normally:

A. Increases

B. Decreases

C. Remains unchanged

D. Becomes intermittent

An increase in left atrial pressure directly raises pulmonary:

A. Alveolar pressure

B. Pleural pressure

C. Capillary pressure

D. Airway pressure

Elevated pulmonary capillary pressure can eventually produce:

A. Bronchial constriction

B. Pleural fibrosis

C. Alveolar vasodilation

D. Pulmonary edema

According to these notes, the greatest force moving fluid into the pulmonary interstitium is:

A. Capillary hydrostatic pressure

B. Colloid osmotic pressure

C. Alveolar air pressure

D. Pleural negative pressure

Before significant pulmonary edema develops, pulmonary capillary pressure must approach the:

A. Plasma colloid osmotic pressure

B. Alveolar oxygen pressure

C. Pulmonary arterial diastolic pressure

D. Pleural fluid pressure