Oxygen therapy in pediatrics

O2 therapy in pediatric COVID-19 patients

1. Oxygen therapy in management of COVID-19 pediatric patients Noha El-Anwar ICU consultant – 57357CCHE Lecturer of pediatrics – Cairo university

2. INDICATIONS • THE OXYGEN DELIVERY SYSTEM METHODS OF OXYGEN DELIVERY ADJUNCTS TO OXYGEN DELIVERY OXYGEN DOSAGE EVALUATION OF RESPONSE TO OXYGEN THERAPY COMPLICATIONS ASSOCIATED WITH OXYGEN THERAPY

3. Indications The main indication is arterial hypoxemia . Severe acute anemia Shock states Acute brain insults (convulsions, coma, increased intracranial pressure)

4. The oxygen delivery system: a) Oxygen source b) Oxygen flow meter c) Oxygen humidifier d) Oxygen delivery equipment e) Oxygen analyzer

5. Methods of Oxygen delivery Oxygen delivery system can be divided into: Positive ventilation (passive) VS negative ventilation (active) Low flow systems (variable performance) VS High flow systems (fixed performance)

6. The method used depends on: 1- patient age 2- patient comfort 3- desired oxygen concentration 4- need to measure the inspired oxygen concentration

7. Low flow systems

8. 1- Nasal Cannula Consist of 2 short soft plastic prongs which are inserted in to the ant. Nares and O2 is delivered into the nasopharynx . Up to 4 L/min of O2 can be used Does not provide humidified oxygen. Indications : low to mod. O2 required, mild or no distress, long term O2 therapy requirement. Contra indication: Poor resp. effort, Apnea, severe hypoxia , mouth breathing. Advantage : Simplicity of use, Patient acceptance, Ability to eat and talk Disadvantage : does not deliver high O2 conc.

9. 2- Reservoir systems

10. 2A-Simple Oxygen mask Minimum oxygen flow of 6L/min should be used Deliver 35% to 60% oxygen with flow rate of 6 to 10 L/ min Indications : Medium flow O2 desired, mild to mod. RD Contra indication: Poor resp. effort, Severe hypoxia, Apnea Advantage : less expensive Disadvantage : does not deliver high conc. O2 , Interferes with eating and talking.

11. 2B- Partial re-breathing mask Simple face mask + reservoir bag Oxygen flow of 10 to 12 L/min is generally required Reliable to provide oxygen concentration of 50% to 60 % Indications : relatively high O2 requirement . Contra indication: Poor resp. effort, Severe hypoxia, Apnea Advantage : inspired gas not mixed with room air Disadvantage : more O2 flow does not increase O2 conc., Interferes with eating and talking.

12. 2C- Non re-breathing mask Face mask + reservoir bag + A valve incorporated into the exhalation port (A valve placed between reservoir bag and mask) Oxygen flow into the mask is adjusted to prevent collapse of bag Inspired concentration of oxygen of 95% can be achieved by 10 to 12L/min of oxygen Well sealed face mask is used Indications : delivery of high conc. Of O2 Contra indication: Poor resp. effort, Apnea Advantage : high conc. O2 without intubation Disadvantage : expensive , Interferes with eating and talking.

13. 3 - Face tent Also known as face shield High flow soft plastic bucket Well tolerated by children then face mask Up to 40% of oxygen can be delivered with 10 to 15 L/min of oxygen flow Access for suctioning is achieved without interrupting the oxygen flow.

14. 4 - Oxygen tent Clear plastic shell that encloses the child’s upper body Provide more then 50% of O2 Not reliable Limits access to patient Cannot be used in emergency situation

15. 5 - Nasal catheter Flexible , lubricated oxygen catheter with multiple holes in distal 2 cm Advanced posteriorly into the pharynx through nostril No advantage over nasal cannula Hemorrhage and gastric distension can occur

16. High flow systems

17. 1- Venturi - type mask Reliable Provide controlled low to moderate (25% to 60 %) of inspired oxygen concentration Indications : desire to deliver exact amount of O2 Contra indication: Poor resp. effort, Severe hypoxia , Apnea Advantage : fine control of FIO2 at a constant flow Disadvantage : expensive, can not deliver high O2 conc . Interferes with eating and talking

18. 2- Oxygen hood Clear plastic shell with covers the patient’s head Well tolerated by infants Allows access to chest, trunk and extremities Permits control of inspired oxygen concentration , temp . and humidity Flow of oxygen- 10-15 L/min 80 to 90 % of oxygen conc. can be achieved Can be used in neonates and infants only.

19. 3- High Flow Nasal Cannula (HFNC)

20. Significant improvement in measures of RD along with improved gas exchange High flow nasal O2 creates positive pressure in nasopharynx . It could act like PEEP to prevent collapse of alveoli at the end of expiration It avoids intubation and mechanical ventilation

21. 4- Bag Valve Mask Ventilation Two hands must be used : One hand- head tilt- chin lift maneuver Other hand- compress ventilation bag •A neutral sniffing position is maintained. • Hyperextension of head is avoided to maintain the optimum position for airway patency. • Distention of stomach frequently occurs. It should be avoided to prevent aspiration.

22. 5- Tracheostomy Collar/ Mask Inserted directed into trachea Is indicated for chronic O2 therapy need O2 flow rate 8 to 10L Provides accurate FIO2 Provides good humidity. Comfortable ,more efficient

23. 6- T-Piece The T-piece is a T-shaped adapter used to provide oxygen to either an endotracheal or Tracheostomy tube. The flow rate should be at least 10 L/min with humidification. Flow can also be provided by a ventilator. Used to provide a high-enough flow rate to ensure that there is a minimal amount of entrained room air.

24. Oropharyngeal Airway Indicated in in unconscious pt. if procedure to open airway fail to provide and maintain a clear , unobstructed airway. Size : corner of mouth to angle of jaw. Insertion… Adjuncts to Oxygen Delivery

25. Oxygen Dosage In emergency situations ( eg . acute cyanosis, shock states), 100% oxygen should be immediately given by a tight non rebreathing face mask or by assisted ventilation with the bag and mask attached to 100% oxygen . In less urgent situations ( eg . RD, arterial hypoxemia), treatment usually starts with an oxygen concentration between 40-60%.

26. Oxygen should be given continuously . Interrupted oxygen therapy is physiologically harmful especially to sick infants and children. Dosage of oxygen can be changed (increased or decreased) according to the response . Changes in dosage are usually made by increaments or decrements of 10% per time. Oxygen therapy should be used for the least possible time . Starting from few hours to several days or several weeks. Oxygen should be withdrawn gradually . With concentrations above 40% decrements by 10% per time are appropriate. With concentrations below 40% decrements should be by 5% per time

27. Evaluation of response to oxygen therapy Response to oxygen therapy can be evaluated clinically and laboratory Measurements of the arterial oxygen saturation (SaO2) and arterial oxygen pressure (PaO2) are the most reliable parameters for evaluation

28. Good response : SaO2 >90% …. Pulse oximeter ,, PaO2 >90mmHg ….. ABG Poor response : Presistant low SaO2 <85% in spite of 60-70% oxygen Presistant arterial hypoxemia <60 mmHg in spite of 60-70% oxygen In this situations of simple oxygen failure, oxygen should be given through positive pressure support (CPAP or MV)

29. Complications associated with oxygen therapy 1- Lung toxicity: Related to both concentration (dosage) and duration of therapy PIO2 and not FIO2 is the main responsible factor for toxicity E xposure to 100% oxygen is toxic to the lungs in 4 hours, while 70% oxygen is toxic in 4 days, 40% oxygen is safe for one month. It is manifested by cessation of mucociliary activity, destruction of oxygen sensitive type I pnematocytes with decreased surfactant production and atelectasia . Hyperplasia o type II pnematocytes and interstitial fibrosis eventually occur.

30. 2- Oxygen dependency and weaning difficults with prolonged oxygen therapy. 3- Retinal toxicity to premature infants.

31. 4- Other Complications : • Drying of mucous membranes. • Skin breakdown • Suppression of ventilation will lead to increased CO2 and narcosis • Potential of contamination and infection to patients. • Absorption atelectasis • Fire Hazard

32. References Pediatric Advance Life Support Paramedic : Airway Management 2011 Pediatric Critical Care Medicine: Basic Science And Clinical Evidence edited by Derek S . Wheeler , Hector R. Wong, Thomas P. Shanley Pediatric critical care, principles of emergency medicine . Edited by Mohammed El- Naggar , 2009.