1. Respiratory failure
Inadequate gas exchange,
causing
hypoxemia <60 ± hypercapnia >45

2. Types
 Type 1-
 Hypoxemia without hypercapnia
 Due to V/Q mismatch
 Caused by parenchymal disease,
PE/shunt, ILD, ARDS
 Type 2-
 Hypoxemia with hypercapnia
 Due to hypoventilation or decreased area for gas
exchange as in emphysema

3. Manifestation
 Of underlying disease +
 Dyspnea, headache +
 Hypoxemia-
 Cyanosis, confusion, tachypnea, tremor, HT, arrythmia
 Hypercapnia-
 Conjunctival hyperemia, HT, tachycardia, tachypnea,
altered sensorium, papilledema, asterixis
s/s are non-specific, high index of suspicion required

4. Diagnosis
ABG
(arterial blood gases)
Find underlying pathology

5. Treatment
 Rx of underlying disorder
 Respiratory support for adequate gas
exchange-
 Supplemental oxygen- canula/mask
 Non-invasive +ve pressure ventilation- COPD
 Mechanical ventilation- apnea, fatigue, ARDS
 Other supportive care-
 Nutrition- enteral route preferred
 Maintain fluid & electrolyte balance
 Decrease risk of UGI bleed & DVT/PE
 Good nursing care

6. Prognosis in mechanically
ventilated for respiratory failure
62% weaned
43% discharged
30% survive to 1 year

7. ARDS
 Acute respiratory distress syndrome
 A hypoxemic respiratory failure
 Characterised by-
 B/L lung infiltrates
 Normal PCWP (<18 mm Hg) or no e/o LVF
 PaO2/FiO2 <200
 Multiple risk factors-
 Sepsis, aspiration, shock
 Trauma- thoracic or non-thoracic
 Multiple blood transfusions, acute pancreatitis

8. Management
 Symptom- tachypnea, dyspnea
 Dx- ABG- hypoxemia, CxR- B/L infiltrates
 Look for other organ dysfunction
 Rx-
 Treat underlying disorder
 Supportive mechanical ventilation-
minimum PEEP & lowest FiO2 to maintain PaO2 >60 mm Hg
 Maintain zero fluid balance i.e. no weight gain
 Px- 30-40% mortality,
~90% mortality if accompanied by sepsis