Transcript Slide 1
Nasal Cannula Intermittent
Mandatory Ventilation
(NC-IMV)
Introduction
With increased survival of very low birth weight (VLBW)
infants, the number of infants who require prolonged
mechanical ventilation (MV) has increased
The pulmonary management of these infants is directed
at minimizing the need for prolonged MV to reduce
ventilator-induced trauma and oxygen toxicity
Early extubation often presents difficulties because of
upper-airway instability, poor respiratory drive, alveolar
atelectasis, and residual lung damage
Khalaf et al Pediatrics 2001; 108:13-17
Background
Use of Nasal respiratory support (NARES)
is on the rise to decrease post-extubation
failures, bronchopulmonary dysplasia
(BPD), and for the treatment of apnea of
prematurity
CPAP, by various means, commonly is
used to wean premature infants from
mechanical ventilation
NCPAP Failure Rates
NCPAP use is associated with failure rates
of 20 to 80% in preterm infants
Reasons for failure include recurrent
apnea/ bradycardia/desaturations or
respiratory acidosis requiring intubation or
re-intubation
Ramanathan et al J Perinatol October 2010; 30:S67-S72
Background
The addition of a back-up rate by using
NIPPV not only adds intermittent
distending pressure above PEEP but also
increases flow delivery in the upper airway
Friedlich et al J Perinatol 1999; 19:413-418
Barrington et al Pediatrics 2001; 107:638-641
NCPAP vs. NIPPV for NARES
Additionally, NIPPV has been shown to
decrease NCPAP failure rates to 5 -20%
Background
Typical nasal interfaces used:
Short bi-nasal prongs
Inca prongs or Argyle Prongs
Nasopharyngeal prongs
Nasal mask with SiPAP machine
Variable flow devices
Infant Flow Drivers with nasal prongs or nasal mask.
Problems with these nasal interfaces
Cumbersome
Mucosal irritation, bleeding, nasal trauma
Obstruction due to secretions in the nose or nasopharynx
Background
High flow nasal cannula systems are
increasingly adopted because of the ease of use
Vapotherm, Fisher Paykel HFNC
However, these HFNC systems have no ability
to measure or limit the pressure delivered to the
baby
There are no pop-off valves in these systems
Only pop-off is at 20 PSI to protect the device and not
to protect the baby
Can generate significant amount of distending
pressures at the nasal interface
Air leaks have been reported
Indications
To facilitate extubation of mechanically
ventilated neonates
As a primary mode of support for neonates
with respiratory distress
Infants with moderate-to-severe apnea
Materials
We use a time-cycled pressure and flow
limited (TCPFL) intermittent mandatory
ventilation via nasal cannula (NC-IMV)
This system gives us the ability to control
pressure and flow rate with the use of
nasal cannula while safely delivering rate,
PIP, PEEP and limit the flow rate to 6 or 7
LPM
Materials
Nasal cannula-short tubing
Connected to larger adapter
Larger circuit
Same humidity, but heating at 40°C
Materials
NC-IMV Set-Up
Set up: Conventional Ventilator (Viasys)
Mode: Time Cycled Pressure Limited SIMV mode
(TCPL-SIMV)
Flow Rate:
Reason: To allow us to be able to control the flow rate.
6 LPM if using Neonatal size Nasal cannula
7 LPM if using Infant size Nasal cannula
IMV rate: started at a maximum of 40 bpm
PIP: Same as the most recent Conventional Ventilator
PIP (max 30 CmsH2O)
PEEP: 5 cmsH2O
Insp. Time: 0.5 seconds
NC-IMV Set-Up
Select appropriate Nasal cannula according to
patient’s size
Babies <1Kg
Babies 1-2.5Kg
Premie NeoTech RAM Nasal Cannula (2.0mm ID)
Newborn NeoTech RAM Nasal Cannula (2.5mm ID)
Babies >2.5Kg
Infant NeoTech RAM Nasal Cannula (3.0mm ID)
Weaning Protocol
Wean PIP first
Once PIP was around 10, rate was decreased
to 10
If infant remained stable, switched to NCCPAP
If infant was stable for 12-24 hours on NCCPAP, switched to low flow nasal cannula
(<2 LPM)
Results: (n=183)
Birth weight (g)
Gestational Age (weeks)
BW < 1500 g (n) (%)
Age @ NC-IMV start (days)
Duration of NC-IMV (days)
NC-IMV Failures, (%)
Range
385 – 4167
23 – 41
109 (60 %)
1 -124
1 - 49
15 (8 %)
No cases of nasal injury or gastric or ear drum perforation were seen
within the 1,168 days of NC-IMV. One pt with
pneumothorax. Now have treated >300pts for >3,000 days of NC-IMV
Ramanathan R, Andaya S et al, SPR Meetings, Vancouver, May 2010
Previous Studies
All infants tolerated NC-IMV
All infants tolerated feeds during NC-IMV
No cases of nasal injury, or gastric perforation
were seen
NC-IMV failure rate requiring intubation in our
study population was 8%
Conclusion
NC-IMV is feasible and well tolerated.
TCPFL NC-IMV allows clinicians to limit pressures and can be
delivered safely to neonates
Therefore, it appears that NC-IMV may be used in facilitating
extubation of mechanically ventilated neonates, as a primary mode
of support for neonates with respiratory distress, and for the
treatment of apnea of prematurity
While reducing obstacles such as mucosal irritation, bleeding, nasal
trauma, or obstruction due to secretions in the nose or nasopharynx.
A NOVEL MEANS FOR DELIVERING NASAL
INTERMITTENT POSITIVE PRESURE VENTILATION
IN INFANTS VIA THE NASAL CANNULA (NC):
MEASUREMENTS OF DELIVERED PARAMETERS IN A
NASAL AIRWAY/LUNG MODEL
NC-IMV
Nasal Cannula Intermittent Mandatory Ventilation (NCIMV) is a novel means of delivering pressure controlled
NIPPV breaths noninvasively to neonates requiring
respiratory support.
We have previously reported that NC-IMV is feasible and
well tolerated in a large number of neonates.
However, pressures or volume delivered to the patient is
not known.
Ramanathan et al Pediatric Academic Society, May 2010; Abstract 1472.217
Hypothesis
NC-IMV is sufficient to provide measurable
ventilation effects and pressure, using 3
different cannula devices, in a lung model
using a realistic "leaky” neonatal airway
model
Objective
To determine the magnitude of pressure and
volume delivered to an infant nasal airway/lung
model
Using different sized nasal cannula
At different peak inspiratory pressure (PIP)
settings during constant flow, time-cycled,
pressure-limited ventilation.
Methods
We configured a neonatal test lung to
simulate an apneic premature infant
(CL:0.8 mL/cmH20; R:75 cmH20/L/sec).
A realistic infant nasal airway model was
attached to the test lung.
Methods
28
week premature infant airway model that was reconstructed from a head CT scan
and a rapid prototyping device
Methods
Schematic of Experimental set-up
Methods
Set up: Conventional Ventilator (Viasys)
Mode: Time Cycled Pressure Limited SIMV mode
(TCPL-SIMV)
Flow Rate: 7-9 LPM
IMV rate: 40 bpm
PEEP: 5 cmsH2O
Insp. Time: 0.5 seconds
The nasal airway was ventilated at PIP of 10, 15, 20, 25,
and 30 cmH20
Methods
Nasal cannulae used
Neonatal nasal cannula (Fisher Paykel,
Auckland, NZ): ID 1.5 mm
Infant nasal cannula (Fisher Paykel,
Auckland, NZ) : ID 1.8 mm
New prototype nasal cannula (Neotech Ram
Nasal Cannula®) : ID of 3 mm
Results with ID 1.5 mm
Fisher Paykel
Neonatal Nasal
Prongs
Results with ID 1.8 mm
Fisher Paykel
Infant Nasal
Prongs
Results with ID 3 mm
Neotech Ram
Nasal
Cannula®
Results
Under all testing conditions, there was
detectable PLUNG, VLUNG, and PEEP during
NC-IMV.
There was a linear relationship between
PIP applied by the ventilator and
VLUNG/PLUNG up to 30 cmH20.
Results
The Neotech Ram Nasal Cannula®
provided greater PLUNG, VLUNG, and PEEP
than the other infant nasal cannulae during
NC-IMV.
Poiseuille’s Law
πr4ΔP
Q = ________
8μL
Increased ID to 3mm
Increased ID of delivery tubing to 3 or 3.5mm
Shortened length of delivery tubing
Changed shape of prongs
Thank You
NCPAP: Extubation Failures ~20-80%
(8 Studies; 2001-2009)
%
90
80
70
60
50
40
30
Bi-Nasal vs.
80
Single
Prongs
IFD vs.
57
VCPAP
38.5 38.1
46
33
24
IFD vs.
BCPAP
29
NCPAP vs.
Surf+NCPAP*
39
33
26
19.7
20
10
0
Davis-01
Stefanescu03
Finer-04
Booth-06
Morley-08
Gupta-09
Sandri-09
Rojas-09
Ramanathan R. J Perinatol 30:S67-S72; October