Introduction

Continuous Positive Airway Pressure (CPAP) is a means of providing respiratory support to neonates with either upper airway obstruction or respiratory failure. Respiratory failure constitutes either failure of ventilation or failure of lung function.

CPAP delivers distending airway pressures and oxygen concentrations via the ventilator without the hazards associated with full endotracheal intubation and mechanical ventilation. The delivery of constant positive pressure to the airway of a spontaneously breathing neonate maintains adequate functional residual capacity within the alveoli to prevent atelectasis and improves oxygen and carbon dioxide exchange within the pulmonary circulation.

 Aim

This guideline is intended to assist in the management of neonates requiring CPAP on the Newborn Intensive Care Unit (Butterfly Ward) at the Royal Children’s Hospital.

This guideline does not include management of a nasopharyngeal tube (NPT) for infants with Pierre Robin Sequence, when the NPT is used to relieve upper airway obstruction. Refer to the separate guideline titled “ Nasopharyngeal Tube Modified for Pierre Robin Sequence ”.

Definition of Terms

• Single nasal prong (SNP): An endotracheal tube that has been cut and shortened at the connector end and inserted via the nostril into the nasopharynx.
• Bi-nasal prong: Specially designed nasal prongs which end at the nasal level.

Indications

• Increased work of breathing – tachypnoea, nasal flaring, grunting, retractions, cyanosis, increasing oxygen requirements
• Oxygen requirement greater than or equal to 30% when on high flow nasal cannula
• Respiratory acidosis on blood gas
• The following conditions when associated with the above signs may be responsive to CPAP
  • Respiratory Distress Syndrome (RDS)
  • Pulmonary oedema
  • Atelectasis
  • Recent extubation
  • Transient Tachypnoea of the newborn (TTN)
  • Tracheomalacia or similar disorder of the lower airway
  • Apnoea of prematurity
    

Contraindications

• Upper airway abnormalities that make CPAP ineffective or dangerous, e.g. choanal atresia, cleft palate, unrepaired trachea-oesophageal fistula
• Congenital Diaphragmatic Hernia pre surgical repair

Complications

Complications related to equipment

• Obstruction of prong due to kinking of prong and/or delivery circuit
• Inefficient delivery due to malposition of bi-nasal prongs/mask
• Skin irritation from securing tapes to the face (SNP)
• Pressure necrosis around nostrils and distortion of the nasal septum due to incorrect strapping and positioning
• Pressure necrosis around head/ears and head molding due to failure to release hat and strapping regularly (bi-nasal prongs)
• High air leak around prongs due to mouth being open (SNP and bi-nasal prongs) or air escaping from other nostril (SNP)

Complications related to infant's clinical condition

• Obstruction of SNP or bi-nasal prongs from secretions
• Pneumothorax
• Pneumomediastinum
• Pulmonary interstitial emphysema
• Decreased cardiac output (due to decreased venous return) with excessive CPAP levels
• Gastric distension and feed intolerance
• Increased work of breathing related to increased airway resistance (related to diameter of SNP or bi-nasal prong)
• Inadequate ventilation
• Medical review is required if the nurse is concerned about any of these potential complications

Management

A medical order is required to initiate CPAP, to alter the level of CPAP delivered, and to discontinue CPAP. These should be documented by the medical officer or neonatal nurse practitioner.
CPAP commencement and ongoing care is the responsibility of the infant's nurse, with the assistance of a second nurse.

Initial CPAP settings 

This should be undertaken in discussion with the NICU consultant or fellow. The usual range of settings are 5-8cmHO, however in some clinical conditions (e.g. bronchiolitis, severe chronic lung disease and tracheal issues) higher CPAP up to 12-14cmHO may be ordered by the NICU consultant. An increase in CPAP may be required from the initial setting if work of breathing, respiratory rate, oxygen requirement, and underlying lung pathology deteriorate.

Delivered CPAP

Commonly the measured CPAP pressure will be lower than the set pressure because of CPAP attenuation within the interface and leak. In general, both should be documented in the EMR Flowsheets and the delivered pressure should not be targeted beyond the usual care of the patient (e.g. repositioning the patient or interface, and being aware of leak through the patient’s mouth). If the clinical situation determines that a specific delivered CPAP pressure should be targeted, the medical officer should document this in the CPAP order along with the range for the maximum and minimum CPAP pressures that are acceptable.

Weaning CPAP settings

CPAP is usually weaned in increments of 1cmH₂O every 12-24 hours.  The timing and rate of weaning will be decided by either the NICU consultant or fellow, in discussion with the infant’s nurse.  The factors to consider when deciding to wean the CPAP include work of breathing, respiratory rate, oxygen requirement, and underlying lung pathology.

Ceasing CPAP

When the infant has demonstrated a stable respiratory pattern on CPAP of 5cmH₂O in <30% oxygen for 12-24 hours, the CPAP may be removed. In some circumstances it may be appropriate to cease CPAP at a higher CPAP level (e.g. in older, larger infants). This decision should be discussed with the NICU medical team before the CPAP is removed from the infant. At times, the NICU medical staff, in discussion with the nurse, may decide to electively change the infant from CPAP to high or low flow nasal cannula oxygen, if deemed appropriate (this requires a medical order).

Determining the CPAP interface to be used

CPAP devices used on Butterfly Ward are:

• Single Nasal Prong
• FlexiTrunk^TM bi-nasal prong/mask system

CPAP is not delivered via full endotracheal tube for neonates on the Butterfly Ward.

The decision of whether to use a SNP or FlexiTrunk^TM is a combined medical and nursing decision. If there are specific clinical indications for a particular interface, medical staff should document this on the CPAP order.

Preferred interfaces

Clinical Situation	Preferred Interface	Rationale
Premature lung disease	FlexiTrunkTM, alternate between nasal prongs and mask Consider HFNC if appropriate	Avoids nasal trauma Reduces attenuation of pressure
CPAP greater than 8cmH2O is required, e.g. post extubation in an infant with congenital diaphragmatic hernia or meconium aspiration syndrome	SNP	Better tolerated Better continuity of CPAP
Bronchiolitis (older infants)	SNP	Better tolerated Better continuity of CPAP
Oesophageal surgery/injury	Avoid CPAP (particularly higher settings) if possible. Consider HFNC. If used SNP may be better tolerated in older infants.	CPAP may increase risk of oesophageal leak particularly if tissues friable
If cycling from CPAP is likely	FlexiTrunkTM	Avoids nasal trauma

 

Single Nasal Prong (SNP)

Important Note: In neonates with upper airway obstruction e.g. neonate with Pierre Robin Sequence (PRS), insertion length differs in that the tube bypasses the obstruction. Consult medical staff for clarification if required. A SNP inserted too deeply will cause the infant to gag or will produce bradycardic episodes from vagal stimulation. 

For further information refer to  Nasopharyngeal Tube (NPT) Modified for PRS RCH nursing guideline. 

Equipment

• Resuscitation equipment, correctly set-up and working
  • Neopuff^TM
  • Suction and appropriate sized catheters
• SLE ventilator functioning correctly with flow sensor removed from the circuit
• Humidifier chamber with temperature control set at “invasive setting”
• Scissors
• Endotracheal tube of appropriate size (below is a guide), pre-cut length to ensure external space of 4-5cm once SNP is inserted (i.e. from nare to manifold)

SNP Size and length guide

Weight of Neonate	ETT Size	Length Inserted (Tied at)
<750g	2.5mm	3cm
750g-2000g	3mm	3-4cm
2000g-3500g	3.5mm	4cm
>3500g	4mm	5cm

• Cotton tie
• Leukoplast^TM tape: 2 pieces each cut into "trouser legs"
• Lubricating gel or use infant's saliva as lubrication 
• Comfeel^TM protectant wafer: 2 pieces each cut to fit under tapes on infant's cheeks
• Face washer: moist and dry
  

Application

• Prepare endotracheal tube, cut to length and cotton ties tied at the correct length
• Place Comfeel^TM on neonate’s cheeks 
• Lubricate SNP with infant’s saliva or lubricating gel
• Suction nasopharyngeal and oropharyngeal passages to clear secretions
• Gently insert SNP and secure with strapping (as per securing an endotracheal tube)
• Connect to ventilator
• Wrap piece of red tape around circuit manifold (where ventilator tubing connects to SNP) to identify the ETT as cut and shortened to become a SNP

Ongoing care and considerations

• Respiratory assessment – 
  • Blood gases as required (determined by clinical condition and previous blood gases)
  • Respiratory rate
  • Heart rate
    
  • Chest rise and fall
    
  • Work of breathing 
    
  • Oxygen requirements
    
  • Pulse oximetry
    
  • Capillary refill time
    
• Maintain neutral thermal environment
  
• Ensure cardio-respiratory and pulse oximetry monitoring, correct alarm settings, and documentation
  
• Ensure hand hygiene at all times 
  
• Ensure patency of SNP: suction as necessary
  
• Consider elective tube changes if secretions are thick or copious, if the SNP strapping becomes loose and the SNP is no longer secure or becomes mobile
  
• Consider aspirating stomach prior to SNP change
  
• Do not put a saline lavage into a SNP as this will result in aspiration of fluid which cannot be removed from the lungs by suctioning the SNP
  
• Enteral feeds can be administered via naso/oro-gastric tube, however due to the increased risk of abdominal distension, ensure increased venting/aspiration of naso/oro-gastric or other gastrostomy tubes, including when on continuous feeds
  
• Change circuit weekly 
  
• For neonates being transported to Medical Imaging, use the portable ventilator with the non-disposable circuit
  
• Adequate attention to pressure area care: especially to nostrils and nasal septum:
  
  • Avoid nasal trauma/erosion by ensuring SNP is always secure and strapping is not loose
    
  • Position SNP in a downward arch to avoid pressure on the nares, ensure CPAP circuit tubing appropriately supported/secure; use of circuit holders/devices to prevent tension on SNP
    
  • Consider using alternate nostrils when changing SNP to avoid pressure area development
    

FlexiTrunk™ (Midline) Bi nasal Prong/Mask

Equipment

• Resuscitation equipment, correctly set-up and working
  • Neopuff^TM
  • Suction and appropriate sized catheters
    
• SLE ventilator functioning correctly with flow sensor removed from the circuit 
• Humidifier chamber with temperature control set at “invasive setting”
• FlexiTrunk^TM equipment, i.e. appropriate sized
  • Nasal tubing (“Trunk”)
    
  • Nasal prong
    
  • Nasal mask 
    
  • Bonnet or head gear
    
• Do not discard any connections as these will be required to connect to transport ventilator
• Do not discard any foam blocks as different foam block heights will be required depending upon whether prongs or mask are used

Application

Refer to  FlexiTrunk^TM – Infant Interface Set-up Guide (video and written instructions are available on this page)

Ongoing Care and Considerations

• Respiratory assessment 
  • Blood gases as required (determined by clinical condition and previous blood gases)
    
  • Respiratory rate
    
  • Heart rate
    
  • Chest rise and fall
    
  • Work of breathing 
    
  • Oxygen requirements
    
  • Pulse oximetry
  • Capillary refill time
    
• Maintain neutral thermal environment
• Ensure cardio-respiratory and pulse oximetry monitoring, correct alarm settings, and documentation
• Ensure hand hygiene at all times 
• Ensure optimum prone positioning only when on full cardiorespiratory monitoring – SIDS guidelines should be reviewed with family when prone positioning is used
• Enteral feeds can be administered via naso/oro-gastric tube, however due to the increased risk of abdominal distension, ensure increased venting/aspiration of naso/oro-gastric or other gastrostomy tubes, including when on continuous feeds
• Change circuit and CPAP cap weekly
• Where there is a scalp intravenous line or amplitude-integrated EEG monitor in-situ, use the head gear instead of the bonnet, or SNP may be more appropriate
• For neonates being transported to Medical Imaging, use the transport ventilator with the disposable lightweight circuits

Adequate attention to pressure area care: refer to  FlexiTrunk^TM – Infant Interface Set-up Guide (video and written instructions are available on this page)

• Summary of main points
  • Ensure correct selection of the size of the hat/prongs. Prongs should fill the nares and not stretch the skin. They should be positioned at least 2mm from the septum to avoid pressure necrosis. Hourly checks of septum integrity is necessary.
  • Alternating (“cycling”) between bi-nasal prongs and mask may help maintain septal integrity. Each neonate should be assessed individually and consider alternating between prongs and mask 4-6 hourly.
  • Correct mask placement is essential. The mask should sit comfortably around the neonate’s nose, it must not occlude the nostrils or touch the septum and should not be over the lip or the eyes.
  • Ensure ventilator tubing is well supported to prevent drag on the nasal interface.

Links

RCH Nursing Guidelines

• Nasopharyngeal Tube Modified for Pierre Robin Sequence
• Continuous Positive Airway Pressure (CPAP) and Non Invasive Ventilation (NIV)
• High flow nasal prongs in NICU
• Pressure Injury Prevention and Management

Manuals

• FlexiTrunk^TM – Infant Interface Set-up Guide (video and written instructions are available on this page)
• MR850 Respiratory Humidifier user instructions

Disclaimer

Please remember to read the disclaimer. 

 

The revision of this nursing guideline was coordinated by Sharlene Pattie, Clinical Nurse Educator, Butterfly Ward, and approved by the Nursing Clinical Effectiveness Committee. Updated October 2023.