To facilitate synchronised non-invasive ventilation, prevent de-recruitment and avoid increased work of breathing and apnoea.
Set up Place Edi catheter and record Edi peak and Edi min.
Initial settings based on indications
Escalation mode from CPAP
Backup mode to treat apnoea
PC above PEEP
Back up rate
(All settings to be tailored according to individual patient requirements)
Usually NAVA level that generates PIP of 16-18 cmH20 provides adequate support
Usually NAVA level that generates PIP of 16-18 cmH20 provides adequate support
For nasal CPAP therapy, choose NIV-NAVA mode and set NAVA to zero. Do not choose nCPAP mode.
Monitoring and optimisation of NIV-NAVA
Ensure Edi catheter is well positioned (refer to picture 7). Nasally inserted Edi catheter is more secure and easier to look after in comparison to oral Edi catheter. Nasal Edi catheter can be used with prongs and mask.
Edi catheter malposition:
P wave on all lines and increasing P wave progressing from 1st to 4th lead- Push in catheter
No P wave and dampened QRS on all 4 leads-Pull out catheter
Larger P and QRS on 1st and 4th waveforms-Catheter curled in-Reinsert
No signal- No respiratory drive
Review regularly and look at the efficiency of seal with the baby’s nose. Note the NAVA level and PIP and Edi’s generated, infant’s breathing effort, spontaneous respiratory rate, percentage back-up assist and any gaseous distention of abdomen.
Regularly review Edi peak (normal 5-15 µV), Edi min (normal <3µV) and percentage backup assist to avoid under or over- support.
If Edi peak is >20 µV consistently- Ensure common causes are addressed e.g. secretions blocking nose or prongs wrongly positioned. Otherwise indicates increase work of breathing. Please increase NAVA level in increments of 0.2 until Edi is persistently below 15 µV and baby is comfortable.
If Edi peak is <5 µV consistently- indicates work of breathing is low. Please decrease NAVA level by 0.1 to 0.2 after discussion with medical staff.
If desaturations & periods of apnoea are worsening do a blood gas and review apnoea time. This may need to be decreased. Please consider change in baby’s condition like RDS worsening, sepsis, IVH, Pneumothorax, abdomen distention, etc.
If Edi peak & Fio2 is increasing and work of breathing worsening- It indicates under-support, increase NAVA level. Other changes could be: Increasing PEEP if Edi min is high and increasing Fio2 or reassessing the infants need for invasive respiratory support
If Edi peak and Edi min are low, Fio2 is decreasing and work of breathing is improving- decrease NAVA level. Other proposed changes can be reducing PEEP (if Edi min is low)
If there is abdominal distention or feed intolerance place another gastric tube into the stomach to vent air out. Use the Edi catheter for feeding and keep the spare gastric tube open.
Weaning from NIV-NAVA
Infant can be transferred to bubble CPAP or High Flow Therapy once the NAVA level is <0.5 and Fio2 <0.30 with Edi peak< 15 µV and Edi min <3 µV.
Review frequency of backup ventilation (Back up PC %) on the trends page and time spent in back up/min. If back-up is frequent consider increasing apnoea time and reducing back up PC rate &/or pressure control to encourage an increase in spontaneous respiratory drive.
There is no recommended weaning of NAVA level and it is based on individual experience. Once infant’s respiratory distress improves, weaning of NAVA level can be quicker. Usually NAVA level is weaned by 0.1-0.2 at a time. If baby does not tolerate weaning return to previous settings.
Troubleshooting on NIV-NAVA
Edi Catheter won’t aspirate
Aspirating Edi catheter may collapse the lumen. They are however designed to be aspirated so gentle adjustment should allow aspiration in case of aspirate measurement.
Edi catheter blocked
As the Edi catheter is incorporated with an electrical probe, the lumen is smaller than a usual nasogastric tube. Therefore it can get blocked by thick viscous medications or thickened feeds. In this case it may be necessary to pass a second nasogastric or orogastric tube.
Excessive leak/Low PEEP disconnection alarm
Means the leak is >15L/min. Review circuit for disconnections, interface and connections to interface. (Most common cause being mouth open, inappropriate interface seal and secretions)
Volume delivery restricted
It means that upper high pressure alarm limit is set low. The pressure is limited to 5cmH2O below the set upper pressure limit, which restricts the volume delivery. Check the ventilator alarm pressure setting. Might need to increase the alarm limits.
No patient effort
Ensure Edi is correctly positioned, if so then patient may be apnoeic in which case back up rate will begin. Consider reducing apnoea time if patient is not adequately supported in back up mode. Both oversedation and overventilation can lead to this alarm. Reduce sedation or backup rate
Suitability of mode of ventilation
Changing NAVA level (increase)
Insufficient Back Up Ventilation seen in extreme prems: may see reduced Edi activity-> can reduce Apnoea time down as low as 1 sec in 0.2 sec increments to give more Backup PC & Resp. Rate
Air in stomach (Aspirate Edi Catheter/OG tube & check positions are correct)
Difference between Conventional and NAVA ventilation
Neural diaphragm (Edi) Trigger
Peak pressure or tidal volume
Peak pressure limit
Initiation of breath
Initiation of breath
Size of breath
Termination of breath
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Section 11 - Care of Muscle Relaxed Infant
The purpose of this section is to outline the management of the Infant who is Muscle Relaxed.
Muscle relaxation eliminates spontaneous respiratory effort therefore the infant must have artificial respiratory support prior to administration of medication. The drugs used for prolonged muscle relaxation are the non-depolarising agents such as Vecuronium bromide or Pancuronium bromide.
This group of drugs block the binding of acetylcholine at the nicotinic receptors preventing an influx of sodium into muscle cells hence depolarisation is prevented, calcium ions are not released and muscle contraction does not occur.
Alcohol Based Hand Rub (ABHR)
Neopuff and Laerdal bag with appropriate sized mask
Notify RMO if signs of spontaneous muscle activity are noted
Ensure pain relief and muscle relaxation is adequate prior to performing care and or procedures
Cluster all cares
Provide rest periods
Ensure correct body alignment
Support all limbs
Nesting to increase infant security
Pressure area care attended regularly
Pressure area care – risks involved in the use of neuromuscular blockade include: skin breakdown, peripheral oedema and muscle atrophy
Use soft bedding such as a sheepskin or gel mattress to facilitate comfort and minimal handling
Implement side to side positioning if not contraindicated
Regular skin inspection
Joint mobility – prolonged neuromuscular relaxation may cause joint contractures, muscle weakness and atrophy:
Implement gentle extension and flexion of the joints if not contraindicated
Maintain joints in the position of function
Oral care – muscle relaxation results in an absent swallow reflex and accumulation of secretions. A side effect of muscle relaxants can be increased production of saliva
Suction should be performed as necessary
Moisten lips and tongue with water or EBM using swab sticks
Lanolin to lips if not under radiant heater
Eye care – neuromuscular blockers eliminate the blink reflex leading to corneal drying with potential for abrasion, ulceration, scaring and infection
Keep eye closed at all times
Avoid pressure on the lower eye when head is turned to the side
Inspection of eyes for signs of infection
Cleanse eyes with cotton swabs and normal saline
Bilateral instillation of artificial tears/ophthalmic lubricant every four hours
Ear protection – neuromuscular blockers produce muscular relaxation of all skeletal muscles including the tensor tynpani and the stapedius. Loud sounds may damage the hearing receptors
Application of earmuffs to one or both ears depending on infant’s position
Reduction of noise in infant’s immediate environment
Urine retention – accumulation of urine can occur, leading to bladder distension and decreased urine output
Urinary catheterisation as per Neonatologist recommendations
The following are recommended
Transcutaneous monitor or
The neuromuscular blocking agent has been administered correctly and safely.
The desired level of muscle relaxation has been achieved
No adverse effects have been reported
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Section 12 - Nitric Oxide (NO) Administration
The purpose of this section is to outline the care of an Infant while receiving inhaled Nitric Oxide (NO).
Inhaled nitric oxide is a selective pulmonary vasodilator used to treat persistent hypertension of the newborn (PPHN).
Persistent pulmonary hypertension of the newborn is a cardiopulmonary disorder characterized by systemic arterial hypoxemia secondary to elevated pulmonary vascular resistance with resultant shunting of pulmonary blood flow to the systemic circulation:
Diversion of blood through fetal shunts (R→L shunts)
Systemic arterial hypoxemia and hypercapnia
Prior to commencing Nitric Oxide preductal oxygen saturations should be targeted >90% and PaO2 between 50-80 mmHg
Alcohol based hand rub (ABHR)
Nitric (NO) delivery line
NO sampling line
Connector for sampling port
Scavenger and tubing Identification bands
Procedures Assemble nitric oxide delivery system and scavenging system (optional)
Check that monthly high and low calibrations have been performed by equipment technician – recorded in book on side of Inovent® machine
If the monthly calibration has not been performed within the last 4 weeks arrange for this to be done by the equipment technician or biomedical engineer
Purge Inovent® system as per this SOP, Section 12 -Nitric Oxide Setup
Connect emergency resuscitation equipment i.e. Neopuff to nitric oxide/oxygen outlet on Inovent®
If the baby requires resuscitation it must be done with the Neopuff and NO with a set flow of 15 litres per minute (this administers 10ppm).
Perform cranial ultrasound if possible prior to commencement of NO therapy in infants <32 weeks gestation to exclude IVH
NO therapy maybe contraindicated in the presence of haemorrhagic brain injury
Perform cardiac echocardiogram if possible, prior to commencement of nitric oxide therapy to confirm the presence of pulmonary hypertension and exclude duct dependent lesions
Nitric oxide should not be administered to neonates with congenital heart disease who depend on a right-to-left shunt or have severe left heart failure
Commence nitric oxide therapy when echo evidence of PPHN and FiO2 >0.4 or oxygenation index exceeds 25 (OI=mean airway pressure x FiO2 x 10/PaO2).
Seek advice from a second consultant neonatologist before commencing nitric oxide therapy on infants < 32 weeks gestation since nitric oxide therapy is less effective in this group and may increase the incidence of severe intracranial haemorrhage.
Commence nitric oxide therapy at 20ppm (Inspired Oxygen (FiO2) 100%)or as directed by consultant
Obtain an arterial blood gas sample 30 minutes after initiation of therapy
If oxygenation improved, continue nitric oxide at 20ppm and wean oxygen slowly as tolerated as per consultants orders which must be written in notes
Once oxygen below 40% NO may be weaned as clinically indicated
Minimise disconnection times to maintain continuity of nitric oxide delivery and maintain therapeutic vasodilatory effects, as nitric oxide has a rapid half life
Use a closed suction system for endotracheal suction in order to minimize disconnection time
Monitor methaemoglobin levels 12 hourly and platelet levels and coagulation profile 24-48 hourly
Nitric oxide concentration should be reduced or discontinued if methaemoglobin levels exceed 5-7 percent
Perform daily low calibration of nitric oxide unit as per instructions in Inovent® manual
Record both NO and NO2 levels on observation chart
NO2 levels above 3 are considered toxic to the neonate and may require nitric oxide therapy to be weaned or discontinued.
Calibration has been performed prior to commencement of NO
Cranial ultrasound and echogram has been performed if required
Arterial Blood Gases have been analysed 30 minutes after commencement or according to clinical direction
Resuscitation has been performed using NO and Neopuff
Weaning from NO has occurred according to clinical condition