Respiratory Failure

Question 1

Hypoxaemia

Answer 1

Inadequate oxygenation of BLOOD
(PaO2 < 80mmHg)
• <60mmHg = SEVERE hypoxaemia
May be acute or chronic

Question 2

Hypoxaemia pathological basis

Answer 2

• V/Q Mismatch
• Hypoventilation > dec. O2 uptake into blood
• Diffusion abnormality > obstructs diffusion
• dec. FIO2
• Ventilation > deadspace ventilation
Perfusion without ventilation > dec. O2 uptake into blood

Question 3

Hypoxia

Answer 3

O2 Delivery to TISSUES is inadequate to meet metabolic needs.

Question 4

hypoxia pathological basis

Answer 4

Results from:

1. Hypoxaemia
2. dec. Cardiac output
3. dec. Haemoglobin
4. inc Metabolic rate (e.g. burns)

Question 5

Hypercapnia

Answer 5

PaCO2 ≥ 50mmHg (normal = 35-45mmHg)

Question 6

Hypercapnia pathological basis

Answer 6

Results from:

1. Hypoventilation
2. Increase V CO2
3. Increased dead space as a fraction of V1

Question 7

Respiratory Distress

Answer 7

Respiratory compensation
Increased sympathetic tone

To remember clinical signs:
¬	Early – RAT
o	Restlessness
o	Anxiety
o	Tachycardia/Tachypnoea

¬ Is Late to – BED
o Bradycardia
o Extreme Restlessness
o Dyspnoea

Question 8

Respiratory Distress:

Respiratory Comp.

Answer 8

Respiratory Compensation
•	inc. RR (tachypnoea) 
•	inc. Accessory muscle use
•	Nasal flaring
•	Recession
o	Intercostal
o	Suprasternal
o	Supraclavicular

Question 9

Respiratory Distress:

Increased sympathetic tone

Answer 9

increase in:
• inc. HR
• inc. BP
• Sweating (diaphoresis)

Question 10

Res. Distress in paeds

Answer 10

¬	In paediatrics – FINES
o	Feeding Difficulty
o	Inspiratory Stridor
o	Nasal flares
o	Expiratory Grunting
o	Sternal Retractions

Question 11

Respiratory Failure

Answer 11

¬ Oxyhaemoglobin Dissociation Curve WRT Respiratory Failure:
o Maintain Hb saturation > 90% to maintain PaO2 above 8 kPa
**Any lower > risk of respiratory failure

Question 12

Type 1 resp. failure:

Answer 12

¬ Hypoxaemia without hypercapnia
PaO2 <60mmHg; <8kPa

symptoms:
•	Restlessness
•	Confusion
•	Aggression
•	Sweating
•	Fitting, convulsions
•	“Plucking”
•	inc. RR, HR, BP
•	ECG Changes
•	Blurred vision, tunnel vision
Pallor

Question 13

RF type 1 mx

Answer 13

• Improve ventilation
o Breathing exercises
o NIV = IPPB or CPAP
non-invasive ventilation …Intermittent Positive pressure breathing … Continuous positive airway pressure

• Mobilise & remove secretions
o ACT’s
Suction

Question 14

Type 2 resp. failure:

Answer 14

¬ Hypoxaemia with hypercapnia
o PaO2 < 60mmHg; <8kPa
PaCO2 > 50mmHg; >6.7kPa

symptoms:
•	Flushed skin
•	Drowsiness
•	Warm peripheries
•	Bounding pulse
•	Headache
•	Convulsions
•	Coma

Question 15

RF type 2 mx

Answer 15

¬ Oxygen therapy
¬ NIV = BiPAP (Bilevel Positive Airway Pressure_
OR
Intubation = SIMV (Synchronized Intermittend Mandatoryl Ventilation - patient recieves 12 gaurenteed breaths or how ever many stated)