Clinical Guidelines (Nursing)

Endotracheal Tube Suction of Ventilated Neonates

  • Introduction

    Endotracheal intubation prevents the cough reflex and interferes with normal muco-ciliary function, therefore increasing airway secretion production and decreasing the ability to clear secretions. Endotracheal tube (ETT) suction is necessary to clear secretions and to maintain airway patency, and to therefore optimise oxygenation and ventilation in a ventilated patient. ETT suction is a common procedure carried out on intubated infants. The goal of ETT suction should be to maximise the amount of secretions removed with minimal adverse effects associated with the procedure. The aim of the guideline is to outline the principles of management for infants requiring ETT suction for clinicians on the Neonatal Unit at the Royal Children's Hospital.

    Definition of Terms

    • Endotracheal Tube (ETT):  An airway catheter inserted into the trachea (windpipe) via the mouth or nose in endotracheal intubation.  On the Neonatal Unit this is usually uncuffed.
    • Endotracheal Intubation:  The placement of a tube into the trachea in order to maintain an open airway in patients who are unable to breathe on their own or maintain their own airway.
    • ETT Suction:  The process of applying a negative pressure to the distal ETT or trachea by introducing a catheter to clear excess, or abnormal, secretions.

    Assessment

    ETT suction should be attended based on a clinical assessment of the infant. It does not need to be attended "routinely" as the inspired gas is warmed and humidified (therefore preventing secretions from drying and occluding the airway).

    Auscultate with stethoscope before and after ETT suction in order to evaluate necessity and effectiveness of the procedure.

    Monitor the infant closely before, during and after the procedure to assess baseline, acute physiological changes and recovery.  Parameters to observe:

    • Oxygen saturation
    • Heart rate
    • Respiratory rate
    • Blood pressure (where possible)
    • TcCO2 (where possible)
    • Respiratory function monitoring (during conventional modes of ventilation), including flow, pressure, tidal volume and minute volume

    Clinical Indications for ETT suction

    • Desaturations
    • Bradycardia
    • Tachycardia
    • Absent chest movement
    • Visible secretions in ETT
    • Increased TcCO2
    • Increased pCO2
    • Irritability
    • Coarse or decreased breath sounds (audible secretions in ETT)
    • Blood pressure fluctuations
    • Recent history of large amounts of thick / tenacious secretions

    Effectiveness of ETT suction should be assessed after the procedure by observing:

    • Improvement in breath sounds
    • Removal of secretions
    • Improved oxygen saturation, transcutaneous CO2, heart rate, blood pressure, respiratory rate
    • Decreased work of breathing, improved chest movement

    Measurement of Length to Suction

    Suction should only be to the tip of the ETT, and should never exceed more than 1cm beyond the tip of the ETT, to prevent mucosal irritation and injury. Measurement of length to suction is to be predetermined at shift commencement.  Length is determined by using the centimetre markings on the ETT; and by adding the length of additional space of the ETT adapter (usually 1-1.5 cm). If patient on HFOV or HFJV, allow for different lengths of adaptors.

    The length for suctioning should be documented on a measuring card that is clearly visible on the cot.

    Management

    Equipment

    • Functioning wall suction unit with suction tubing connected (checked at shift commencement)
    • Neopuff set to ventilator settings (checked at shift commencement)
    • Suction catheter (see table below for appropriate sizes)
    • Non sterile gloves
    • Normal saline ampoule and 2 ml syringe (if normal saline lavage required)

    Procedure

    • Where possible, this procedure requires two clinicians.  If clinician deems it necessary, she/he may undertake the procedure without assistance and in this situation should alert other members of staff in the room that ETT suction is occurring.
    • Explain to parents what is about to occur.
    • To determine suction catheter size:

     

    ETT Size (mm)   Suction Catheter Size
    2.5   5 FG
    3.0 - 3.5  6 - 7 FG
    4.0 - 4.5   8 FG

     

    • Set the suction pressure at 80-100 cmH20.  Suction pressure may be lower for a small or unstable infant, or higher to remove thick or tenacious secretions.  If unsure, discuss with AUM or CNS.
    • Primary clinician washes hands, dons gloves on both hands and attaches appropriate sized suction catheter to suction tubing, ensuring that the suction catheter does not touch anything that could contaminate it e.g. bed linen, the outside of the ETT.
    • Observe pre-suction physiological parameters.
    • Pre-silence ventilator and monitor alarms.
    • When the primary clinician and assistant are ready, assistant disconnects ETT from ventilator tubing at ETT adaptor. For HFOV use the suction port on the suction swivel adaptor. For HFJV use the suction port at the end of the ETT adaptor.
    • Primary clinician passes suction catheter to predetermined length, ensuring catheter is only passed the length of the ETTApplying negative pressure, primary clinician gently rotates suction catheter as it is being withdrawn from the ETT
      • Negative pressure should only be applied when the suction catheter is being withdrawn from the ETT.  If patient on HFJV - suction is to be applied during insertion and withdrawal from ETT)
      • Duration of negative pressure should not exceed 6 seconds to prevent hypoxaemia
      • Repetitive catheter passes are not used unless the volume of secretions rationalises another pass, or the clinician determines another pass is necessary
    • To prevent accidental extubation, assistant gently holds infant's head in steady position and holds ETT steady while primary clinician suctions ETT. 
    • Assistant reconnects ventilator tubing to ETT when ETT suction complete, and continues to provide containment and comfort to the infant. If infant on HFOV, assistant may need to press re-set button on oscillator (if oscillator depressurises and stops during ETT suction) to re-start oscillator.
    • Allow the infant to rest prior to attending oropharyngeal and nasopharyngeal suction.  The primary clinician suctions infant's oropharynx and nasopharynx.  Oropharyngeal and nasopharyngeal suction allows removal of secretions which accumulate in the oropharynx and nasopharynx.  A size 8 or 10 FG tube may be used to suction the oropharynx.
    • Observe infant's post-suction physiological parameters.
    • A small amount of sterile water may be used to clear secretions from suction tubing.
    • Turn off vacuum pressure. Dispose of contaminated catheter and gloves and wash hands.
    • Adjust ventilator settings to pre-suctioning baseline (if settings have been adjusted) when indicated by stabilisation of infant's oxygen saturations and heart rate.
    • Ensure infant is left in a contained and comfortable position.
    • Document effectiveness of and tolerance to suctioning.
    • If the infant requires ETT suction, and a second clinician is unable to assist, the procedure is as above, however the primary clinician will need to detach the ETT from the ventilator with one hand, steady the tube using the same hand and insert the catheter to predetermined length using "clean" hand.  Care is especially required to steady the ETT and infant's head to ensure the infant does not accidentally self-extubate.

    Pre-suction procedures

    The following procedures can be used but should not be performed routinely:

    Complications

    Complications of ETT suction:

    • Hypoxaemia
    • Atelectasis
    • Bradycardia
    • Tachycardia
    • Increased TcCO2
    • Blood pressure fluctuations
    • Decreased tidal volume
    • Airway mucosal trauma
    • ETT dislodgement
    • Pneumothorax
    • Pneumomediastinum
    • Bacteraemia
    • Pneumonia
    • Fluctuations in intracranial pressure and cerebral blood flow velocity

    Complications of oropharyngeal and nasopharyngeal suction:

    • Hypoxia
    • Bradycardia


    Documentation

    Document clearly on the MR100:

    • amount, consistency, colour of secretions
    • whether normal saline lavage, hyper-oxygenation, hyperinflation or hyperventilation were required and rationales
    • infant's tolerance of suction procedure
      • degree of desaturation and amount of time to return to baseline
      • degree of TcCO2 changes and amount of time to return to baseline
      • degree of bradycardia and amount of time to return to baseline
      • any other physiological or behavioural changes


    Family Centred Care

    It is the responsibility of the clinician caring for the infant requiring ETT suction to ensure that the parents understand the rationale for the procedure, as well as potential complications.

    Special Considerations

    • Infection Control: Maintain standard precautions
    • Patient Safety: Where possible, ETT suction is a 2 person procedure.  The primary clinician suctions the ETT maintaining infection control precautions.  The assistant ensures the infant remains safe from accidental extubation, adjusts ventilator settings if necessary, and provides containment and comfort to the infant.

    Evidence Table

    Evidence table for Endotracheal Tube Suction of Ventilated Neonates

    Please remember to read the disclaimer.

    The development of this clinical guideline was coordinated by Sharlene Pattie, Clinical Nurse Educator, McKinnon Nursing Education. Approved by the Clinical Effectiveness Committee. Authorised by Bernadette Twomey, Executive Director Nursing Services. First published May 2009, current as of December 2012.