What Are the Basic Oxygen Delivery Methods?

Patient Presentation
A 6-month-old female came to clinic with mild fever, copious rhinitis and poor fluid intake for 48 hours. Children at her daycare had respiratory syncytial virus and her symptoms were getting worse over the past 8 hours with no fluid intake. The past medical history showed a healthy infant who had received influenza vaccine.

The pertinent physical exam showed a respiratory rate of 62, pulse of 119, temperature of 37.8° and an oxygen saturation of 87%. HEENT showed copious clear rhinorrhea. Lungs had mild wheezing. She had intercostal retractions and nasal flaring, but no abdominal breathing and no trachael tugging. The rest of her examination was normal. The diagnosis of probable respiratory syncytial virus (RSV) and hypoxia was made. She was placed on oxygen at 45% FiO2 with nasal prongs and her saturations increased to 95%. She was admitted to the hospital for oxygen therapy. Over the next 48 hours she was slowly weaned off oxygen and was orally rehydrated. The laboratory evaluation confirmed RSV.

Discussion
Oxygen is the most common element on earth. It makes up 21% of air, 89% of seawater and 46% of the earth’s crust. It is a highly reactive element (including being highly flammable) that must be combined to be stable (O2 molecular form) and non-reactive at ambient temperature and pressure.

A continuous supply of oxygen is necessary for human life and lack of oxygen leads to hypoxic brain damage and other end organ damage such as the liver, kidneys and heart. Thus in hypoxic situations, emergency oxygen use is necessary.

Situations where O2 is necessary in high concentrations includes major trauma, shock, sepsis, cardiac arrest, and poisoning with cyanide or carbon monoxide. Other situations where oxygen is likely needed to keep within the saturation range of 94-98% include asthma, pneumonia, heart failure and pulmonary embolism. Additional situations where a lower saturation range (88-92%) are wanted but oxygen is still necessary include diseases where an element of hypercapnea is normal and include cystic fibrosis, chronic neuromuscular disease, hypoventilation syndromes and morbid obesity, COPD and some congenital heart disease. Oxygen therapy is also used for altitude sickness, decompression sickness, wound therapy and other indications.

The target saturations are based on S-shaped oxygen-hemoglobin saturation curve. Below ~88% saturation the curve’s slope is steep and small changes in the partial pressure of oxygen correspond to inadequate oxygen binding to hemoglobin and thus ineffectively delivery of adequate oxygen to tissues.

Learning Point
Oxygen is relatively inexpensive itself, but the equipment to deliver it and monitor the therapy can be more expensive. Equipment varies by availability, ease of patient use or preference, amount of flow or rate, oxygen concentration and the ability to apply positive pressure.

Basic options for non-invasive oxygen therapy include:

  • Nasal canula or prongs (View Image) – easy to adjust flow and concentration at any time, comfortable for patients to use and relatively inexpensive.
  • Simple facemask (View Image) – similar to nasal canula but other patients find this more comfortable.
  • Venturi mask (View Image) – specifically controls concentration and flow, good for patients who are oxygen-sensitive.
  • Reservoir mask (View Image) – also known as a non-rebreather, for patients who are critically hypoxemic or ill, often used until other oxygen delivery methods can be used.

Basic options for non-invasive ventilation include:

  • CPAP (View Image) – continuous positive airway pressure, has a tight-fitting mask or helmet nasalpharyngeal prongs. The patient usually is spontaneously breathing, but PEEP (positive end expiratory pressure) is increased from normal. NPCPAP is commonly used in ill preterm infants. Nightime CPAP is often used for obstructive sleep apnea.
  • NIPSV – non-invasive pressure support ventilation is sometimes called BIPAP (bilevel positive airway pressure) or Bilevel PS (bilevel pressure support). This uses a ventilator to assist the patient by applying both PEEP at the end of expiration but also additional pressure during inspiration. The patient is not intubated in the traditional sense but the ventilator assists the patient.

Options for ventilators today mainly include positive pressure ventilation, and high frequency oscillatory ventilation.

Among these various basic delivery methods are variations and refinements.

In developed countries these oxygen delivery methods are widely available, but in resource-limited settings across the world where more than 99% of the mortality of children 70 bpm, head nodding, grunting, chest retractions, nasal flaring, lethargy, central cyanosis and inability to eat or drink.

Questions for Further Discussion
1. What are the oxygen delivery methods available locally?
2. How can a respiratory therapist be helpful in the evaluation and treatment of a patient with respiratory distress?
3. What other medication can be delivered along with oxygen therapy?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Oxygen Therapy and Respiratory Syncytial Virus Infections.

To view current news articles on this topic check Google News.

Masip J. Non-invasive ventilation. Heart Fail Rev. 2007 Jun;12(2):119-24.

Rojas MX, Granados Rugeles C, Charry-Anzola LP.Oxygen therapy for lower respiratory tract infections in children between 3 months and 15 years of age. Cochrane Database Syst Rev. 2009 Jan 21;(1):CD005975.

O’Driscoll R. Emergency oxygen use. BMJ 2012;345:e6856.

Encycloaedia Britannica Online, s. v. “oxygen (O),” accessed March 05, 2013, http://www.britannica.com/EBchecked/topic/436806/oxygen.

Ralston ME, Day LT, Slusher TM, Musa NL, Doss HS. Global paediatric advanced life support: improving child survival in limited-resource settings. Lancet. 2013 Jan 19;381(9862):256-65.

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competently performed.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Systems Based Practice
    23. Differing types of medical practice and delivery systems including methods of controlling health care costs and allocating resources are known.
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.

    Author

    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital