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

  • What Causes Digital Clubbing?

    Patient Presentation
    A 4-year-old female came to the emergency room with fever and mild respiratory distress and cough. She had recently immigrated from Mexico. The past medical history was negative for surgeries and hospitalizations, and her immunizations were not current. The review of systems revealed that she had a poor appetite, poor growth, no sweats or actual weight loss. there was no hematemesis The social history showed that the family had been in several transitory housing situations over the past several months, where various residents had been ill with gastrointestinal illnesses and coughs.

    The pertinent physical exam showed a tired-appearing female. She had a temperature of 38.2°, respiratory rate of 40, pulse of 118, and saturation of 87% on room air. Her weight was 50% for a 3.5 year old, and her height was 10% for age. HEENT showed copious rhinitis. Lungs had wheezing and crackles bilaterally. She had multiple lymph nodes in the anterior and cervical chains (all were <1.0 cm). No supraclavicular nodes. She also had several bilateral groin nodes (also all < 1.0 cm). Her hands showed bilateral clubbing of the digits. Her toes did not have clubbing. The work-up included a chest radiograph that was suggestive of tuberculosis. The diagnosis of suspected tuberculosis was made and she was admitted. Pulmonary tuberculosis was confirmed by a positive PPD and QFT gold test and the patient was started on medications. A respiratory viral panel also confirmed concomitant respiratory syncytial virus. Public health was contacted and they investigated the family and other potential contacts. Prior to discharge, the family was assisted in finding primary care home where followup and preventive care (including immunizations) would be given. At follow-up at 1 month, the patient was taking her medication and was improving.

    Case Image
    Figure 103 – PA and lateral radiographs of the chest (from another patient) demonstrate prominent bilateral hilar lymphadenopathy, which is suggestive of a diagnosis of tuberculosis. The lungs are otherwise clear.

    Discussion
    Clubbing is a uniform swelling of the terminal digital phalynx with loss of the normal angle between the nail and nail bed (i.e. Lovibond angle). the earliest sign is periungual erythema, then filling in of the angle between the proximal nailbed and the soft tissue of the finger just beneath the cuticle. This usually has a normal angle of around 160 °. The angle then begins to straighten out (i.e. 180°) and the nail base has a floating or springy sensation when palpated. With late clubbing there is visible swelling and the angle exceeds 180° and tissues are shiny and tense. With severe clubbing there is swelling of the terminal part of the digit causing it to appear like a drumstick. Rounding and beaking of the distal nail bed in the absense of other signs of clubbing is familial and not indicative of disease. Clubbing is usually painless and patients and family members may not notice. Clubbing usually occurs bilaterally but can occur unilaterally.

    The exact pathophysiological mechanism for each cause of clubbing is unknown but an increase in vascular endothelial growth factor appears to be an important common pathway. Vascular endothelial growth factor causes vascular hyperplasia, edema, and fibroblast or osteoblast proliferation in the distal nails.

    For images of clubbing see To Learn More below in the image search.

    Learning Point
    Digital clubbing is not a common general pediatric problem, but certainly not uncommon in particular patient populations such as patients with congenital heart disease, cystic fibrosis and other chronic lung or gastrointestinal diseases.

    The differential diagnosis of clubbing includes:

    • Cardiac
      • Congenital heart disease with cyanosis
      • Infective endocarditis
      • AV malformations
    • Endocrine
      • Acromegaly
      • Hyperthryoidism
      • Hyperparthryoidism
    • Gastrointestinal
      • Achalasia
      • Celiac disease
      • Cirrhosis
      • Crohn’s disease
      • Tropical sprue
      • Ulcerative colitis
    • Infectious disease
      • Tuberculosis
    • Pulmonary
      • Cystic fibrosis
      • Interstitial lung disease – particularly bronchiectesis, but this is a large differential diagnosis itself.
      • Abscess and empyema
      • Lung cancer – primary and metastatic
      • Sarcoidosis
    • Other
      • Hypertrophic osteopathy – primary and secondary
      • Malignancy
      • Palmoplantar keratoderma
      • Pregnancy
      • Pseudoclubbing

    Questions for Further Discussion
    1. What is the current treatment for pulmonary tuberculosis in the United States?
    2. What initial laboratory evaluation would you do for clubbing?

    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, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

    Information prescriptions for patients can be found at MedlinePlus for this topic: Finger Injuries and Disorders

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

    To view images related to this topic check Google Images.

    Bates B. A Guide to Physical Examination. Third edition. J.B. Lippincott Co. Philadelphia 1983;53.

    Avery ME, First LR. Pediatric Medicine. 2nd Edit. Williams and Wilkins 1989;259,486.

    Rudolph CD, et.al. Rudolph’s Pediatrics. 21st edit. McGraw-Hill, New York, NY. 2003:1754.

    Rajagopalan M, Schwartz RA. Evaluation of Clubbing. ePocrates Online.
    Available from the Internet at https://online.epocrates.com/u/2912623/Evaluation+of+clubbing/Differential/Etiology (rev. 1/25/13, cited 3/4/13).

    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.
    8. Health care services aimed at preventing health problems or maintaining health are provided.

  • 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.

  • Practice Based Learning and Improvement
    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.

  • Systems Based Practice
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.
    25. Quality patient care and assisting patients in dealing with system complexities is advocated.
    26. Partnering with health care managers and health care providers to assess, coordinate, and improve health care and how these activities can affect system performance are known.

    Author

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

  • How Do Airway Malacias Present?

    Patient Presentation
    While working on the general pediatric inpatient service, a pediatrician had 4 patients with similar stories.
    All were under 1 year of age and were admitted for respiratory distress, cough and dehydration due to respiratory syncytial virus.
    Each had a prolonged illness or needed readmission because each also had an underlying airway malacia that had been diagnosed by bronchoscopy – laryngomalacia, tracheomalacia, tracheobronchomalacia and bronchomalacia.
    The patient with laryngomalacia also had inspiratory stridor during this admission. Those with lower airway malacias originally were diagnosed after having a chronic cough, poor weight gain, and/or had additional underlying disease problems (i.e. genetic syndrome).
    The residents all had noted that the farther down in the airway the malacia was, the more ill the patient was clinically and/or had other underlying disease problems.
    This offered a good chance to review how airway malacias can present.

    Discussion
    Stridor is a variably pitched sound caused by increased turbulence and airflow through a narrowed part of the large airway. Usually due to narrowing of the larynx or extrathoracic trachea, stridor is usually inspiratory.
    Biphasic stridor usually is due to a fixed airway obstruction at the level of the glottis or subglottis but may also extend to the mid-thoracic trachea.

    Stridor is different than stertor which is a heavy-snoring, inspiratory sound occurring in coma or deep sleep, sometimes due to obstruction of the larynx or upper airways. Causes of stertor include choanal stenosis, enlarged tonsils and/or adenoids, and redundant upper airway tissues above the larynx.

    Causes of upper airway obstruction that can cause stridor include:

    • Acute laryngotracheobronchitis (i.e. croup)
    • Epiglottitis
    • Hereditary angioneurotic edema
    • Intubation, post-endotracheal
    • Laryngomalacia
    • Laryngeal cleft
    • Laryngeal cysts
    • Micrognathia or retrognathia
    • Mucus retention cysts
    • Subglottic stenosis
    • Thyroglossal duct remnant
    • Vocal cord paralysis – forceps delivery, Chiari malformation

    Learning Point
    Malacia means a softening of the tissues and is named by its location.

    Laryngomalacia usually presents with noisy breathing and inspiratory stridor. There can be collapse of the arytenoids, epiglottis, and aryepiglottic folds.
    Symptoms usually present around 10 days, worsen for the next several months, and then resolve by 2 years of age.
    It is considered a developmental process and is usually benign.
    Laryngomalacia can be associated with other airway malacias. In one study, concomitant tracheomalacia (29%) bronchomalacia (10%) and tracheobronchomalacia (7%) were identified.

    Recurrent wheeze, chronic cough and recurrent respiratory tract illnesses were common problems seen in patients with both laryngomalacia and another airway malacias.

    Tracheomalacia is a localized or generalized “…weakness of the trachea which causes luminal obstruction at times of increased intrathoracic pressure, such as expiration or coughing.” Tracheobronchomalacia involves both the trachea and bronchi, and bronchomalacia involves the bronchus.
    Patients with all 3 intrinsic airway malacia types may have minor respiratory infections but they can also cause apnea, cyanosis and life-threatening airway obstruction. Chronic coughing and wheezing are common presentations. Most have increased illness severity during acute illnesses and take longer to resolve.
    The airway malacias may be part of other congenital anomalies (including cardiac anomalies) and therefore be more difficult to treat. Treatment can include surgical (e.g. aortopexy, tracheopexy, external or internal airway stenting), and mechanical (positive airway pressure). These airway malacias often do not resolve and therefore may require treatment.

    Questions for Further Discussion
    1. What are indications for bronchoscopy?
    2. What different delivery methods are there for oxygen therapy?

    Related Cases

    To Learn More
    To view pediatric review articles on these topics from the past year check
    PubMed – Laryngomalacia,
    PubMed – Tracheomalacia, and
    PubMed – Bronchomalacia.

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

    Information prescriptions for patients can be found at MedlinePlus for these topics: Breathing Problems and Tracheal Disorders.

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

    To view images related to this topic check Google Images.

    Eber E. Evaluation of the upper airway. Paediatr Respir Rev. 2004 Mar;5(1):9-16.

    Vijayasekaran D, Gowrishankar NC, Kalpana S, Vivekanandan VE, Balakrishnan MS, Suresh S. Lower airway anomalies in infants with laryngomalacia. Indian J Pediatr. 2010 Apr;77(4):403-6.

    Masters IB, Zimmerman PV, Pandeya N, Petsky HL, Wilson SB, Chang AB. Quantified tracheobronchomalacia disorders and their clinical profiles in children. Chest. 2008 Feb;133(2):461-7.

    Calkoen EE, Gabra HO, Roebuck DJ, Kiely E, Elliott MJ. Aortopexy as treatment for tracheo-bronchomalacia in children: an 18-year single-center experience. Pediatr Crit Care Med. 2011 Sep;12(5):545-51.

    Goyal V, Masters IB, Chang AB. Interventions for primary (intrinsic) tracheomalacia in children. Cochrane Database Syst Rev. 2012 Oct 17;10:CD005304.

    Midyat L, Cakır E, Kut A. Upper airway abnormalities detected in children using flexible bronchoscopy. Int J Pediatr Otorhinolaryngol. 2012 Apr;76(4):560-3.

    ACGME Competencies Highlighted by Case

  • Patient Care
    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.

  • Practice Based Learning and Improvement
    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.
    16. Learning of students and other health care professionals is facilitated.

    Author

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

  • How Common Is Bullous Myringitis?

    Patient Presentation
    A 2-year-old female came to clinic after 16 hours of severe right ear pain. She had fever to 38.5° and was being given ibuprofen. Previously she had rhinorrhea for 3 days but no cough. The past medical history showed an episode of otitis media 7 months previously. The review of systems was otherwise negative. The pertinent physical exam showed a cranky female with normal vital signs and growth parameters in the 90-95% for age. HEENT revealed moderate rhinorrhea, normal pharynx and eyes. Her left tympanic membrane was erythematous with mild bulging, distorted landmarks and immobility. Her right tympanic membrane was very erythematous with an orange hue, and was dramatically bulging with 3 blisters on the lower 1/2 of the membrane. The rest of her examination was negative. The diagnosis of bullous myringitis was made and amoxicillin-clavalaunic acid was given. The parents were told to use acetaminophen or ibuprofen for pain relief and told that because the blisters were relatively friable there was a chance that one could break and the child would have otorrhea. The patient was to follow-up in about 4 weeks to recheck the ear.

    Discussion
    Bullous myringitis (BM) is felt to be a variation of acute otitis media (AOM) with more severe symptoms. Bullae (blisters or “balloons”) on the tympanic membrane occur between the outer epithelial layer and middle fibrous layers of the tympanic membrane. The exact reason for this is unknown but felt to be probably due to a strong inflammatory reaction in the middle ear begun by viral or bacterial pathogens. The pain is felt to be due to irritation of the highly innervated outer epithelial layer. The most common pathogens are the same as AOM but Streptococcus pneumoniae is detected more often. The bullae can occur on the tympanic membrane but also extend to the proximal aspect of the external ear canal (in about 10% of BM cases). Bullae that only involve the external canal are due to otitis externa and should be distinguished from BM. Symptoms that are present more often in patients with BM than AOM include severe earache and fever, but also ear rubbing, poor sleep, more crying and decreased appetite.

    While most cases are due to infectious diseases, one case in the literature reported BM due to organic solvent (paint thinner) entering the nasal cavity and into the middle ear with what appeared to be direct cellular damage to the structures.

    The American Academy of Pediatrics recently updated their clinical practice guidelines for the treatment of acute otitis media in children. See To Learn More below.

    Learning Point
    Overall, BM is felt to occur in < 10% of patients with AOM. One prospective longitudinal cohort study found of 2028 children followed from 2-24 months, they had 1876 visits for AOM (1876/2028 = 92.5%) in 2683 ears. Eighty-six visits were for BM (86/1876 = 4.6%) in 92 ears. Bullae spread from the tympanic membrane to the external canal in 9 ears (9/92 = 9.8%).

    Questions for Further Discussion
    1. What is the difference between pneumatic otoscopy and tympanometry? How do they help to determine if AOM is present?
    2. What other treatment(s) besides antibiotics can be offered for BM?

    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, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

    Information prescriptions for patients can be found at MedlinePlus for this topic: Ear Infections

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

    To view images related to this topic check Google Images.

    McCormick DP, Saeed KA, Pittman C, Baldwin CD, Friedman N, Teichgraeber DC, Chonmaitree T. Bullous myringitis: a case-control study. Pediatrics. 2003 Oct;112(4):982-6.

    Minoda R, Miwa T, Sanuki T, Yumoto E. An unusual cause of bullous myringitis with acute otitis media. Otolaryngol Head Neck Surg. 2011 Nov;145(5):874-5.

    Kotikoski MJ, Palmu AA, Puhakka HJ. The symptoms and clinical course of acute bullous myringitis in children less than two years of age. Int J Pediatr Otorhinolaryngol. 2003 Feb;67(2):165-72.

    Liberthal AS, Carroll AE, Chonmaitree T et al. The Diagnosis and Management of Acute Otitis Media. Pediatrics. 2013. Available from the Internet at: http://pediatrics.aappublications.org/content/early/2013/02/20/peds.2012-3488.abstract (rev. 2/25/13, cited 2/25/13).

    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.
    5. Patients and their families are counseled and educated.
    8. Health care services aimed at preventing health problems or maintaining health are provided.

  • 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.

    Author

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