Chapter 2

Question 1

Define respiratory failure

Answer 1

Inadequate gas exchange due to dysfunction of one or more of essential components of the respiratory system

Question 2

What is a consequenc of respiratory failure?

Answer 2

Inability to maintain oxygen and/or carbon dioxide levels at normal levels

Question 3

What is a sign of impaired ventilation?

Answer 3

Increased carbon dioxide levels

Question 4

How to measure oxygenation of the blood?

Answer 4

1. Pulse Oximeter
2. Arterial Blood Gas

Question 5

What 5 components of the human body can fail that leads to respiratory failure?

Answer 5

1. CNS and nerves
2. Chest wall/diaphragm
3. Airways
4. Alveolar-capillary units
5. Pulmonary Circulation

Question 6

What are the symptoms of respiratory failure?

Answer 6

1. Breathlessnes
2. Consequences of hypoxia - pulmonary HTN and secondary heart strain; polycythaemia due to EPO release from kidney

Question 7

State and explain the two types of respiratory failure.

Answer 7

Type 1 - Hypoxaemia without hypercapnia
- low oxygen levels but able to maintain ventilation so carbon dioxide is normal or low
- main problem is failure of alveolar-capillary units which are the sites of gas exchange
i.e. flooding of alveolar spaces by fluid/pus; pulmonary embolism; collapsed lung; loss of normal alveolar structures due to irreversible damage

Type 2 - hypoxemia with hypercapnia
- also a component of poor ventilation resulting in retention of CO2
i.e., failure of neuromuscular system; failure of chest wall mechanics; airway obstruction

Question 8

What is the progression of respiratory failure?

Answer 8

Progression of disease (more of lung affected) or exhaustion of patient reaches a point where compensatory measures (ie hyperventilation, tachycardia etc.) fail

Exhaustion and insufficient oxygen supply to brain result in ventilation problems and hypercapnia

Question 9

What two factors cause death of patients with respiratory failure?

Answer 9

1. Hypoxia
2. Acidosis