Oxygen

History

  • Use of Supplemental Oxygen was First Reported in 1890

Indications

Extension of Apnea Time During Endotracheal Intubation

  • Clinical Efficacy
    • Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) Increases Apnea Time During Endotracheal Intubation (Anaesthesia, 2015) [MEDLINE]: high-flow nasal supplemental oxygen (during pre-oxygenation and continuing as post-oxygenation during intravenous induction of anaesthesia and neuromuscular blockade until airway was secured) increases the apnea time during endotracheal intubation
      • Proposed Mechanism: combines the benefits of classical apneic oxygenation with continuous positive airway pressure and gaseous exchange through flow-dependent deadspace flushing
    • Trial of High-Flow Nasal Cannula During Endotracheal Intubation (Crit Care Med, 2015) [MEDLINE]: high-flow nasal cannula oxygen significantly improved preoxygenation and reduced the prevalence of severe hypoxemia compared with non-rebreathing bag reservoir facemask

High Altitude (see High Altitude, [[High Altitude]])

General Comments

  • Requirement for Supplemental Oxygen at Altitude Can Be Determined Using Both Hypoxia Altitude Simulation Test (HAST) and 6-Minute Walk Test (6MWT)

Hypoxia Altitude Simulation Test (HAST) (see Hypoxia Altitude Simulation Test, [[Hypoxia Altitude Simulation Test]])

  • HAST Interpretation
    • pO2 >55 mm Hg During HAST: no supplemental oxygen is required
    • pO2 50-55 mm Hg During HAST: considered borderline -> measurement with activity can then be obtained
    • pO2 <50 m Hg During HAST: testing with supplemental oxygen (usually 2L/min) is performed

6-Minute Walk Test (6MWT) (see 6-Minute Walk Test, [[6-Minute Walk Test]])

Clinical Data
  • Comparative Study of 6MWT and Hypoxia Altitude Simulation Test (HAST) in Patients with Either Interstitial Lung Disease or COPD (Aviat Space Environ Med, 2007) [MEDLINE]
    • Oxygen Desaturation Induced by the 6MWT Correlated with that After HAST (r = 0.52)
  • Study of Algorithm Using Resting/6WMT SpO2 and HAST in COPD Patients (Thorax, 2012) [MEDLINE]
    • Baseline SpO2 <92%: supplemental oxygen is required for air travel
    • Baseline SpO2 92-95%
      • 6MWT SpO2 <84%: supplemental oxygen is required for air travel
      • 6MWT SpO2 ≥84%:
        • HAST SpO2 ≤85%: supplemental oxygen is required for air travel
        • HAST SpO2 >85%: no supplemental oxygen is required for air travel
    • Baseline SpO2 >95%
      • 6MWT SpO2 <84%
        • HAST SpO2 ≤85%: supplemental oxygen is required for air travel
        • HAST SpO2 >85%: no supplemental oxygen is required for air travel
      • 6MWT SpO2 ≥84%: no supplemental oxygen is required for air travel

Hypoxemia (see Hypoxemia, [[Hypoxemia]])

  • xxxx

Pulmonary Hypertension (see Pulmonary Hypertension, [[Pulmonary Hypertension]])

  • xxxx

Respiratory Failure (see Respiratory Failure, [[Respiratory Failure]])

  • Acute Hypoxemic Respiratory Failure
  • Chronic Hypoxemic Respiratory Failure
  • Chronic Hypoxemic-Hypercapnic Respiratory Failure

Supportive Therapy During General Anesthesia

  • xxx

Pharmacology

  • Oxygen

Administration

Nasal Cannula (NC)

  • xxx

High-Flow Nasal Cannula (HFNC)

General Comments

  • Rationale: high-flow nasal cannula appears to decrease dead space [MEDLINE]
  • Contraindications
    • Hypercapnic Respiratory Failure
    • Mid-Maxillary Facial Trauma
    • Suspected Pneumothorax

Clinical Efficacy

  • French FLORALI Study Comparing High-Flow Nasal Cannula Oxygen with Standard Oxygen and Non-Invasive Ventilation in Hypoxemic, Non-Hypercapnic Respiratory Failure (NEJM, 2015) [MEDLINE]
    • No Difference in Intubation Rates
    • High-Flow Oxygen Group: improved 90-day mortality and ventilator-free days
    • Criticism of Study: the noninvasive ventilation group was unconventionally ventilated with 9 ml/kg PBW, possibly increasing lung injury in this group
  • Spanish Trial of High-Flow Nasal Cannula vs Conventional Oxygen Therapy in Extubated Patients at Low Risk of Reintubation (JAMA, 2016) [MEDLINE]: multicenter randomized trial in Spain
    • In Extubated Patients at Low Risk of Reintubation, High-Flow Nasal Cannula Decreased the Risk of Reintubation within 72 hrs, as Compared to Conventional Oxygen Therapy

Ventimask

  • xxx

Non-Rebreather Mask

  • xxx

Mechanical Ventilation (see Mechanical Ventilation-General, [[Mechanical Ventilation-General]])

  • xxx

Adverse Effects

Pulmonary Adverse Effects

Oxygen Toxicity

  • Physiology
    • Mechanisms by Which High Oxygen Concentrations Exacerbate or Contribute to Development of Lung Injury
      • Formation of short-lived free oxidant radicals -> damage to DNS, lipid membranes, and intracellular enzymes
      • Direct injury to endothelial cells and type I epithelial cells -> alveolar capillary leak
    • Volunteer Studies: breathing 100% oxygen for 6-48 hrs variably induced a tracheobronchitis, substernal burning, chest tightness, dry cough
      • PFT’s: decreased VC and DLCO
    • Tolerance of Hyperoxia: appears to be related to ability to generate antioxidants
      • Some evidence that this ability is genetically determined
    • Phases of Oxygen Toxicity (phases overlap)
      • Acute/Exudative Phase: usually begins within 48-72 hrs (depending on inspired oxygen fraction) -> reversibles
        • Perivascular, interstitial, and alveolar edema -> atelectasis and alveolar hemorrhage
      • Subacute/Proliferative Phase: usually begins after 4th-7th day -> irreversible
        • Rebsorption of exudates
        • Hyperplasia of type II pneumocytes
        • Deposition of collagen and elastin in interstitium and hyaline membrane deposition
  • Clinical
  • Treatment
    • Preventive Measures: maintain pO2 <80 mmHg and FIO2 <40-50%

Worsening of Hypercapnia in Hypercapnic COPD Patients (see Chronic Obstructive Pulmonary Disease, [[Chronic Obstructive Pulmonary Disease]])

  • Physiology
    • Excess Oxygen May Blunt the Hypoxic Ventilatory Drive
    • Excess Oyxgen May Increase Physiologic Dead Space: due to oxygen-induced bronchodilation in poorly-perfused areas of the lung

Other Adverse Effects

  • xxx

References

  • The continuous inhalation of oxygen in cases of pneumonia otherwise fatal, and in other diseases. Boston Med J 1890;123:481-5
  • High-flow oxygen administration by nasal cannula for adult and perinatal patients. Respir Care 2013;58:98-122
  • Nasal high-flow versus Venturi mask oxygen therapy after extubation: effects on oxygenation, comfort, and clinical outcome. Am J Respir Crit Care Med 2014;190:282-8
  • Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE): a physiological method of increasing apnoea time in patients with difficult airways. Anaesthesia 2015;70:323-9 [MEDLINE]
  • FLORALI Study. High-flow oxygen through nasal cannula in acute hypoxemic respiratory failure. N Engl J Med 2015. DOI: 10.1056/NEJMoa1503326 [MEDLINE]
  • Saving lives with high-flow nasal oxygen. N Engl J Med. 2015 Jun 4;372(23):2225-6. doi: 10.1056/NEJMe1504852. Epub 2015 May 17 [MEDLINE]
  • High-flow nasal cannula oxygen therapy in adults. J Intensive Care. 2015 Mar 31;3(1):15. doi: 10.1186/s40560-015-0084-5. eCollection 2015 [MEDLINE]
  • Nasal high-flow versus Venturi mask oxygen therapy after extubation. Effects on oxygenation, comfort, and clinical outcome. Am J Respir Crit Care Med. 2014;190:282–288 [MEDLINE]
  • Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE): a physiological method of increasing apnoea time in patients with difficult airways. Anaesthesia 2015;70:323-9 [MEDLINE]
  • Use of high-flow nasal cannula oxygen therapy to prevent desaturation during tracheal intubation of intensive care patients with mild-to-moderate hypoxemia. Crit Care Med. 2015;43:574–583 [MEDLINE]
  • Heated humidified high-flow nasal oxygen in adults: mechanisms of action and clinical implications. Chest. 2015;148(1):253–261 [MEDLINE]
  • Use of high-flow nasal cannula oxygen therapy in subjects with ARDS: a 1-year observational study. Respir Care. 2015;60:162–169 [MEDLINE]
  • Effect of Postextubation High-Flow Nasal Cannula vs Conventional Oxygen Therapy on Reintubation in Low-Risk Patients: A Randomized Clinical Trial. JAMA. 2016;315(13):1354 [MEDLINE]

High Altitude (see High Altitude, [[High Altitude]])

  • Aerospace Medical Association. Medical guidelines for airline travel, 2nd ed. Aviat Space Environ Med 2003; 74:A1–A19 [MEDLINE]
  • Walking capacity and fitness to fly in patients with chronic respiratory disease. Aviat Space Environ Med 2007;78:789–792 [MEDLINE]
  • Hypoxia altitude simulation test. Chest. 2008 Apr;133(4):1002-5. doi: 10.1378/chest.07-1354 [MEDLINE]
  • The hypoxia altitude simulation test: an increasingly performed test for the evaluation of patients prior to air travel. Chest. 2008 Apr;133(4):839-42. doi: 10.1378/chest.08-0335 [MEDLINE]
  • Flying with respiratory disease. Respiration. 2010;80(2):161-70. doi: 10.1159/000313425. Epub 2010 Apr 16 [MEDLINE]
  • Air travel and chronic obstructive pulmonary disease: a new algorithm for pre-flight evaluation. Thorax. 2012 Nov;67(11):964-9. doi: 10.1136/thoraxjnl-2012-201855. Epub 2012 Jul 5 [MEDLINE]