Oxygen Rx

1
Oxygen Rx

• The art of passing gas to save a life

2
Goals or Clinical Outcomes

• Reduce or correct hypoxemia
• Reduce myocardial work (WOH)
• Reduce work of breathing (WOB)

3
Indications for O2 Rx

• PaO2 lt 60 torr
• SaO2 lt 90 with normal Hb level
• Evidence of tissue hypoxia
• Central cyanosis
• Peripheral cyanosis
• Oxygen desaturation with mild to moderate exercise

4
Indications for O2 Rx

• Any acute or chronic disease, disorder, or acute
  complications that result in hypoxemia
• MI
• CHF
• Acute or chronic pulmonary disorder
• Cor pulmonale

5
Hazards/Complications

• Respiratory depression
• Oxygen induced hypoventilation aka hypoxic drive
• Atelectasis from nitrogen washout
• Oxygen toxicity
• Exudative phase (24-72 hours)
• Proliferative phase (gt 72 hours)

6
Hazards/Complications

• Exudative phase
• Damage to type I alveolar cells or pneumocytes,
  which are flattened cells that form the alveoli
• Damage to type II alveolar cells or pneumocytes,
  which produce, secrete, and store surfactant
• Hemorrhage, edema, hyaline membrane formation

7
Hazards/Complications

• Retinopathy of prematurity
• Decreased mucociliary transport

8
S/S of Acute Hypoxemia

• Tachycardia-first sign
• Tachypnea
• Hyperpnea
• Dyspnea-patients point of view of SOB
• Altered sensorium
• Headache
• Dusky, pallor, cyanosis

9
Hypoxias

• Hypoxic hypoxia
• Decreased oxygen in the blood
• ? oxygen in the inspired gas, e.g., high altitude
• Alveolar hypoventilation
• V/Q mismatch
• Anatomic and capillary shunting

10
Anemic (Hemic) Hypoxia

• Reduced carrying capacity
• Decreased Hb and Hct, e.g., blood loss
• Carbon monoxide poisoning
• Methhemoglobinemia
• Ferric (Fe2) instead of ferrous (Fe3)
• Sickle cell anemia
• Altered RBC shape to counter malaria

11
Stagnant (Circulatory) Hypoxia

• Reduced perfusion
• Cardiac arrest
• Shock
• Embolus
• Left heart failure

12
Histotoxic Hypoxia

• Impaired oxidative enzyme mechanism
• At the cellular or tissue level
• RBC cannot use oxygen
• Cyanide poisoning

13
High Flow System 1

• A system that provides consistent, precise, and
  measurable oxygen that meets or exceeds the
  patients inspiratory flow and the concentration
  is not altered inspite of the patients changing
  breathing pattern

14
High Flow System 2

• A system that delivers a consistent oxygen
  concentration regardless of the patients
  breathing pattern, provided the total flow of the
  system at a given FiO2 meets or exceeds the
  patients inspiratory flow.