ROYAL FREE LONDON NHS FOUNDATION TRUSTPAEDIATRIC GUIDELINES

Humidified High Flow Nasal Oxygen Therapy in children

Author(s): Lynn Sinitsky, Paediatrician; Michael Clift, Lead Practice

Educator, Children’s Services

Contact author: Michael Clift, Lead Practice Educator, Children’s Services

Other contributors: Krishnakumar Jada, Paediatrician

Previous authors: n/a

Related guidelines or documents:

Guidelines for the Use of Humidified High Flow Nasal

Oxygen Therapy in Neonates (2015)

Approved by: The Paediatric Guidelines Group on behalf of the Women,

Children and Imaging Services Division

Issue no (Version): December 2016 v3

File name: High flow oxygen therapy for children

Key words: (up to 10) Bronchiolitis, respiratory distress, High flow, oxygen, nasal

cannula, Vapotherm, Optiflow

Supercedes: n/a

Significant change in practice:

Increasing use of High flow oxygen therapy for children as

opposed to continuous positive airway pressure

Implementation plan: Publish on freenet, publicise in quality and safety bulletins,

risk meetings, high dependency skills study days, learning

through multi-disciplinary simulation

Service Line Lead Paediatrics: Rahul ChodhariClinical Director for Paediatrics

Tim Wickham

Divisional Director of Nursing

Mae Buckley

For Review: January 2019

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ContentsContents........................................................................................................................2Introduction....................................................................................................................3Background....................................................................................................................3Clinical management......................................................................................................4Nursing care...................................................................................................................8Equipment......................................................................................................................9References....................................................................................................................17Monitoring compliance................................................................................................18APPENDIX 1: MONITORING TOOL........................................................................19APPENDIX 2: EQUALITY ANALYSIS checklist.....................................................20

EQUALITY STATEMENT

The equality analysis for this guideline is in Appendix 2.

The Royal Free London NHS Foundation Trust is committed to creating a positive culture of respect for all individuals, including job applicants, employees, patients, their families and carers as well as community partners. The intention is, as required by the Equality Act 2010, to identify, remove or minimise discriminatory practice in the nine named protected characteristics of age, disability (including HIV status), gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religion or belief, sex or sexual orientation. It is also intended to use the Human Rights Act 1998 to treat fairly and value equality of opportunity regardless of socio-economic status, domestic circumstances, employment status, political affiliation or trade union membership, and to promote positive practice and value the diversity of all individuals and communities.

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INTRODUCTIONThe aim of this guideline is to describe the indications and procedures for non-invasive respiratory support using humidified high flow nasal oxygen therapy in term infants and children. This guideline will focus on two humidified high flow nasal oxygen therapy systems used in the Trust: Optiflow and Vapotherm.

The use of humidified high flow nasal oxygen therapy in children in the Trust is primarily for use in children with bronchiolitis. This guideline is to be used in conjunction with the bronchiolitis guideline. Humidified high flow nasal oxygen therapy can be used in other conditions such as pneumonia, asthma and sickle cell disease but evidence is limited. Therefore, at present, its use in conditions other than bronchiolitis should be on an individual patient basis and only with consultant approval.

BACKGROUNDConventional treatment for bronchiolitis is supportive and includes fluids, supplemental oxygen and respiratory support. Respiratory support may be non-invasive, either CPAP or humidified high flow nasal oxygen therapy, or invasive, intubation and ventilation. Traditionally non-invasive support was provided as CPAP. Although very effective (only 1 in 5 babies on CPAP deteriorate and require intubation and ventilation1) CPAP may be uncomfortable, especially for older infants, and it is rarely associated with side effects such as pneumothoraces.

Humidified high flow nasal oxygen therapy has become more available over the past decade as an alternative system for non-invasive respiratory support2-7. Humidified high flow nasal oxygen therapy enables delivery of higher inspired gas flows of an air/oxygen blend and provides some level of continuous positive airway pressure to improve ventilation. Retrospective studies2-7 have shown that humidified high flow nasal oxygen therapy is:

feasible; well tolerated; can reduce the work of breathing in infants with bronchiolitis; and associated with reduced intubation and mechanical ventilation rates.

At present, it is unclear whether CPAP or humidified high flow nasal oxygen therapy is better at preventing deterioration and so the need for intubation and mechanical ventilation in babies with severe bronchiolitis. In 2015 a preliminary randomised controlled trial took place in the UK that the Royal Free took part in, comparing the feasibility and effectiveness of CPAP versus high flow nasal oxygen therapy8. The results have not been published yet.

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CLINICAL MANAGEMENTIndications

Respiratory support in patients with moderate/severe respiratory distress from bronchiolitis

Respiratory support in other conditions, e.g. pneumonia, pneumonitis, asthma, tracheo-bronchomalacia, sickle cell disease, neuromuscular disease, on an individual patient basis and only with consultant approval.

Oxygen requirement of >30% or >2L/min via nasal prongs Poor tolerance of CPAP mask Where increased humidity is beneficial to help with clearance of secretions To improve patient comfort while they require respiratory support by enabling

them to eat, drink and talk

Contraindications

Recurrent apnoeas Pneumothorax Upper airway obstruction including croup, epiglottitis, suspected tracheitis Following traumatic injury (Base of skull fracture, Maxillofacial Trauma) Facial and nasal abnormalities, Complete nasal obstruction In the child in whom improvement on nCPAP is unlikely and requires full

mechanical ventilation Caution required in children with suspected abdominal distension Loss of airway protective reflexes Persistent vomiting Excessive or rapidly increasing requirements

These are the same contraindications as for CPAP.

Use with caution where there is:

Reduced level of consciousness Cardiac instability Pneumothorax with drain in situ

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Initiating humidified high flow nasal oxygen therapy

In the Trust there are two humidified high flow nasal oxygen therapy systems in use: Vapotherm Precision Flow

Fisher Paykel Optiflow

Refer to the EQUIPMENT section for instructions on the set-up for each system.

* Ensure Oxygen is prescribed on the Drug chart *

A) Flow rate

The flow rate is determined by the weight of the child and limited by the size of the cannula chosen.

As a guide the maximum flow rate for a patient should be 2L/kg body weight/min, up to a maximal recommended flow rate of 30L/min. as per Table 1 below

In adult patients providing a flow rate of 30L/min ensures that most if not all of the patient’s breath is humidified and oxygenated at a rate that is tolerable.

The maximum recommended flow rate for the appropriate sized nasal cannula is as per Table 1 below and is also written on the manufacturer’s packaging and summarised in Tables 2 and 3 below.

Start at the maximum indicated flow rate. You may need to lower the flow rate initially while patient adjusts to flow rate and

humidity. This should only take a few minutes. With an adequate flow an improvement in respiratory rate, respiratory effort and

heart rate should be seen within 15 minutes hence reason for starting at maximum8.

Table 1 Maximum recommended flow rates

Weight (Kg) Maximum flow rate (L/min)3 64 85 106 127 148 169 1810 20

TABLES 2 AND 3 FOR MANUFACTER SPECIFIC DETAILS OVERLEAF

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Table 2 Maximum recommended flow rates for the appropriate sized nasal cannula with Optiflow

Cannula size Maximum flow rate Appropriate age range

Appropriate weight range

Neonatal OPT 3148L/minuse junior circuit

27 weeks – 6 months 1-8 kg

Infant OPT 31620L/minUse junior circuit Term - 3-5 years 3-15 kg

Paediatric OPT 31825L/minUse junior circuit 1 – 6 years 12-22 kg

Children MR850

Use clinical judgement to decide whether to use Optiflow Junior or the Optiflow Adult system with small/medium adult cannula (based on comfortable cannula fit on child’s face/nares)

30L/minuse adult circuit Over 6 years Over 22 kg

Tracheostomy

Use ‘Adult’ Optiflow system with OPT 570 Tracheostomy connector

All weights

Table 3 Maximum recommended flow rates for the appropriate sized nasal cannula with Vapotherm

Cannula size Maximum flow rate Appropriate age range

Appropriate weight range

Premature (MN 1100A) 1-8 0 – 30 days < 4kgs

Neonatal (MN 1100B) 1-8 0 – 30 days < 4kgs

Infant (MI 1300) 1-8 1 month – 1 year 4 – 10kgs

Intermediate infant (MI 1300B) 1-8 1 month – 1 year 4 – 10kgs

Pediatric small (MPS1500) 1-20 1 – 6 years 10 – 20kgs

Pediatric/Adult Small (MP1500) 5-40 6 – 12 years 20 – 40kgs

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AB) Oxygen

Start at FiO2 30% Aim for oxygen saturations > 92 % If FiO2 ≥ 50% needs urgent medical review

* Ensure Oxygen is prescribed on the Drug chart *

Nursing of patients on humidified high flow nasal oxygen therapy

Nurse in high-dependency isolation. 1:2 Nurse: Patient ratio Continuous heart rate and oxygen saturation monitoring Half hourly recording of systemic observations including PEWS for the first 2

hours Hourly recording of systemic observations after 2 hours if patient is improving Observing and recording work of breathing/use of accessory muscles as part of

observations Blood gas measurement within 1st hour of commencing High flow. Hourly fluid balance monitoring Daily U&E if on IV fluids

Monitoring response to therapy

All patients should be assessed within 20 minutes of starting humidified high flow nasal oxygen therapy to determine response to treatment. With adequate flow rates, an improvement in the patient’s condition should be seen by this time.

If there is an improvement in the patient’s clinical condition within 20 minutes of starting humidified high flow nasal oxygen therapy, treatment should be continued with regular clinical assessments and a blood gas in the first hour..

Urgent medical review is needed if any of the following occurs: Patient not stabilising Sudden deterioration in respiratory status Trend towards deteriorating respiratory status e.g. increasing respiratory

rate Degree of respiratory distress worsens Hypoxaemia (oxygen saturations <92%) persists despite high gas flow

and ≥>=50% FiO2

Management once established on HFOV therapy

All patients should be assessed by a Paediatric Consultant at least once every 24 hours.

If not able to start weaning off HFOV by day 3 of therapy and/or still requiring HFOV after 5 days of therapy:

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R eview underlying cause R eview for potential complications D iscuss with CATS for potential paediatric HDU transfer

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Potential complications

Sudden clinical deterioration requiring immediate assessment for intubation and ventilation

Potential barotrauma leading to surgical emphysema and/or pneumothoraces Aspiration of feed. Gastric distention and diaphragmatic splinting Obstruction or irritation due to improper sizing of nasal cannulae Pressure areas

Treatment success

Success of treatment can be seen by: Reduction in oxygen requirement Reduction in heart rate and respiratory rate Reduction in work of breathing Improvement in respiratory acidosis

Once the patient’s clinical condition has improved as indicated by normal/minimal work of breathing and normal respiratory and cardiovascular parameters, weaning off therapy can begin (see below).

Weaning

The optimum way to wean humidified high flow nasal oxygen therapy remains unclear.

Standard practice is to wean the oxygen requirement first to FiO2 30% and then to wean the flow rate.

The flow rate is weaned by 1-2L/min to a minimum of 1L/kg/min OR 6 L/min if < 6kg in weight according to clinical response.Note: The nasal prongs of the high flow circuits may be slightly bigger than the low flow prongs. At low flow rates, a patient’s work of breathing can increase because of insufficient ambient air being drawn through the cannula. This is the reason for the minimum flow rates above.

At this minimum flow rate, oxygen can then be weaned further until FiO2 is 0.21% before discontinuing therapy completely or the patient can be changed to a standard low flow oxygen device.

Treatment failure

Failure of treatment can be seen by: Apnoea’s Increasing oxygen requirement or FiO2 ≥> 50% Unchanged/ rising heart rate and respiratory rate Failure to improve respiratory acidosis An unchanged or increased work of breathing SpO2 < 92% at FiO2 0.8 and flow rate >8L/min High pCO2 on blood gas at 1 hour post starting therapy - high positive

predicative value for failure.

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If failure:

Check circuit and nasal cannulae position Consultant review (Paediatrician and Anaesthetist) and consider change

to CPAP or need for intubation and ventilation. In the meantime:

o Review diagnosiso Consider chest X-ray

NURSING CARE Nurse in high-dependency isolation. 1:2 Nurse: Patient ratio

Airway

Gentle suction as required to keep nares and mouth clear. Check position of nasal prongs and no pressure areas to nares 2-4 hourly.

(Prongs not occluding >50% of nares)

Check humidifier water level and temperature hourly.

Observations

Continuous heart rate and oxygen saturation monitoring Half hourly respiratory rate including PEWS for the first 2 hours Hourly recording of systemic observations after 2 hours if patient is improving Observing and recording work of breathing/use of accessory muscles as part of

observations

Fluids and nutrition

Hourly fluid balance monitoring All infants on high flow therapy should have a nasogastric tube inserted. Once stable on high flow, the infant should be assessed as to whether they can

feed. Some infants can continue to breast/bottle feed, but most require feeding via a nasogastric tube.

Regularly (2-4 hourly) aspirate the nasogastric tube for air to prevent gastric distention and splinting.

Daily U&E if on IV fluids

Other cares

Oral, nasal and Eeye cares should be performed 2-4 hourly. Check position of nasal prongs and no pressure areas to nares 2-4 hourly.

(Prongs not occluding >50% of nares) Gentle suction as required to keep nares clear.

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Check humidifier water level and temperature hourly.

Equipment

Check humidifier water level and temperature hourly.

EQUIPMENTOptiflow set-up (see written instructions and pictorial guide below)

Equipment:

Airvo 2 Humidifier with integrated flow generator Patient circuit and chamber kit (Optiflow or Optiflow junior) Appropriate nasal cannula, not occluding >50% of the nostril. 1 litre sterile water bag Check bedside and ensure a working suction, correct size bag valve mask

and the correct size high flow oxygen and mask (non-rebreathe) are available

Assembling:

1. Insert humidification chamber2. Attach sterile bag of water3. Connect the blue wide end of the circuit to the top of Airvo 24. Cut out and attach oxygen tubing from the port on the left of the machine

to the wall oxygen. 5. Turn on device, check device is on the correct mode (animated critters

are visible in junior mode) – to change the mode press and hold the play button for 5 seconds

6. Choose from rate as per medical advice (see table for guidance) 7. Adjust oxygen flow to achieve desired FiO2 8. When the tick appears on the screen, fix the interface to the patient and

connect device tubing. 9. Spare wigglepads can be used to secure and readjust the interface rather

than using a whole new one. 10. The temperature is automatically set on 34°C in Junior mode.

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Prongs

There are a range of prongs available for the neonatal and paediatric age range. Prongs should not fit tightly and should not form a seal (see table 1 for more information) and the guide below for application:

o

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Circuit and humidifier

Set-up the circuit and humidifier according to the pictorial guide:

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Optiflow resources

Fisher & Paykel (2016) Airvo 2 User manual [Online] http://www.rch.org.au/uploadedFiles/Main/Content/rchcpg/AIRVO%202%20Humidifier%20user%20manual.pdf [Accessed on 14th July 2016)

Fisher & Paykel (2016) Infant Nasal High Flow: Clinical Paper Summaries {online] https://www.fphcare.co.uk/CMSPages/GetFile.aspx?guid=db85b48c-b23f-4c91-83e6-06c892c5aa3e [Accessed on 14th July 2016)

Fisher & Paykel (2016) Optiflow [Online] https://www.fphcare.co.uk/resources-downloads/alphabetical-listing/o/?page=3 [Accessed on 14th July 2016)

Vapotherm set-up (see written instructions and pictorial guide below)

Equipment

Vapotherm device High or low flow cartridge and circuit (according to age. See CIRCUIT

below) Appropriate nasal cannula, not occluding >50% of the nostril (See Table

2) 1 litre sterile water bag Check bedside and ensure a working suction, correct size bag valve mask

and the correct size high flow oxygen and mask (non-rebreathe) are available

Assembling:

1. Obtain Vapotherm device and correct sized nasal cannula from equipment cupboard.

2. Obtain correct cartridge/disposable package from equipment cupboard. (Low flow cartridge: 1 – 8 lpm; High flow cartridge: 5 – 40 lpm).

3. Insert cartridge into disposable water path by lining up ports and press firmly into place (see guide below)

4. Slide door on the unit forward and, while holding the disposable water path by the handle, insert it with the delivery tube facing downward.

5. Slide then patient circuit down until it stops and close the door6. Plug in power cord in receptacle at bedside and connect air/oxygen source to

blender and rear of unit. 7. Allow the unit to perform its pre-use check 8. Hang closed sterile 1000 ml water bag on pole. Spike the water bag and allow

approximately 200 mls of water to drain into the patient circuit.9. Press the run/standby button to start gas flow, pump and heater.

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10. Adjust flow, FiO2 and temperature to desired settings.11. Allow the set temperature to be achieved before placing the nasal cannula on

the patient

Prongs

There are a wide range of prongs available for the full neonatal and paediatric age range. Prongs should not fit tightly and should not form a seal. (see table 2 and here)

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Circuit

There are low flow and high flow circuits. The choice is dependent on the age of the patient and subsequent prong size used:

Prongs Circuit choicepremature, neonatal, infant & intermediate infant nasal cannula

Low Flow: 1-8 lpm

Pediatric nasal cannula & 8-40 lpm with adult nasal cannula

High Flow: 5-20 lpm

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Vapotherm resources

Vapotherm (2016) Precision Flow® Operating Instruction Manual [Online] http://cdn.vtherm.com/public/246/documents/Current-Version-20141027124246-Documents-246-9906-1.pdf [Accessed on 14th July 2016]

Vapotherm (2016) Precision Flow® Quick reference guide [Online] http://cdn.vtherm.com/public/246/documents/Current-Version-20141027124035-Documents-246-14553-1.pdf [Accessed on 14th July 2016]

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REFERENCES

1. Donlan M, Fontela PS, Puligandla PS. Use of continuous positive airway pressure (CPAP) in acute viral bronchiolitis: a systematic review. Pediatr Pulmonol. 2011 Aug;46(8):736-46

2. Mckiernan C, Chua lC, Visintainer PF, Allen HM. High flow nasal cannulae therapy in infants with bronchiolitis. Journal of Pediatrics 2010; 156(4): 634-638

3. A Schibler, TMT Pham, KR Dunster, K Foster, A Barlow, K Gibbons, JL Hough. Reduced intubation rates for infants after introduction of high-flow nasal prong oxygen delivery. Intensive Care Medicine 2011

4. Wing R, James C, Maranda LS, Armsby CC. Use of high-flow nasal cannula support in the emergency department reduces the need for intubation in pediatric acute respiratory insufficiency. Pediatric Emergency Care 2012; 28(11): 1117-1123

5. Milési C, Baleine J, Matecki S, Durand S, Combes C, Novais ARB, Combonie G. Is treatment with a high flow nasal cannula effective in acute viral bronchiolitis? A physiologic study. Intensive Care Medicine 2013; 39 (6): 1088-1094

6. Beggs S, Wong ZH, Kaul S, Ogden KJ, Walters JA. High-flow nasal cannula therapy for infants with bronchiolitis. Cochrane Database Syst Rev. 2014 Jan 20;1

7. Ramnarayan P et al. A randomised controlled trial of high flow nasal cannula therapy (HFNC) versus continuous positive airway pressure (CPAP) in infants with severe bronchiolitis: a feasibility study. 2016

8. Trang M.T., O’Malley L. Mayfield S., Marton S. and Schibler A. The effect of High Flow Nasal Cannula therapy on the work of breathing in infants with bronchiolitis. Pediatr Pulmonol 2015 Jul 21;50(7):713-20

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MONITORING COMPLIANCEThis guideline will be subject to annual audit and multidisciplinary review as

described in the monitoring table in Appendix 1.

Element to be monitored

Lead Tool Frequency Reporting arrangements

Acting on recommendations and Lead(s)

Clinical management of bronchiolitis

Dr Lynn Sinitsky, Consultant Paediatrician

Notes audit review

Yearly Paediatrics Clinical Audit/Governance meeting

Dr Lynn Sinitsky, Consultant Paediatrician

Case notes review of any patient requiring HFOV therapy for greater than 5 days.

Dr Lynn Sinitsky, Consultant Paediatrician

HDU RECALL tool

Ongoing Paediatrics Clinical Audit/Governance meeting

Dr Lynn Sinitsky, Consultant Paediatrician

Incidents related to bronchiolitis management

Sumayyah Hajjaj, Paediatric Risk Manager; Michael Clift, Lead Practice Educator, Children’s services; Rahul Chodri, Consultant Paediatrician

Datix risk management monitoring

Live via risk reporting

Paediatric risk and review meeting

Acute paediatric matrons; Lead Practice Educator, Children’s services; Rahul Chodri. Service line lead, Paediatrics

Vapotherm and Optiflow equipment training

Michael Clift, Lead Practice Educator, Children’s services

Education and training database

Ongoing Monthly Children’s services clinical practice education meetings

Michael Clift, Lead Practice Educator, Children’s services

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APPENDIX 1: MONITORING TOOL

APPENDIX 2: EQUALITY ANALYSIS CHECKLISTRoyal Free London NHS Foundation Trust Equality Analysis Name of the policy / function / service development being assessedBriefly describe its aims and objectives:Directorate and Lead:

Evidence sources: DH, legislation. JSNA, audits, patient and staff feedback

Is the Trust Equality Statement present?

Protected Characteristic(Equality Act 2010)

Identify negative impacts

What evidence, engagement or audit has been used?

How will you address the issues identified?

Age

Disability

Gender ReassignmentMarriage and Civil PartnershipPregnancy and maternityRace

Religion or BeliefSex

Sexual OrientationCarers

It is important to record the names of everyone who has contributed to the policy, practice, function, business case, project or service change.

Equality Analysis completed by: (please include every person who has read or commented and approval committee(s). Add more lines if necessary)

Role and organisation if appropriate

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