Are You Optimizing Every
Bilevel Breath?
Jim Eddins, RRT
Objectives
• Discuss the basics of non-invasive
ventilation and the benefits of using NIV
• Discuss features that improve bilevel
tolerance
• Determine the most effective bilevel
settings based on disease state
Consider Using NIV When …
Patient is not tolerating
high pressure settings or
is complaining of
inability to exhale,
despite expiratory
pressure relief feature
Respirations are
characterized by CSA,
CSR or CompSA
Use NIV
Obstructive events
persist at 15 cm H2O
Patient has a history of
ventilatory insufficiency
Utilizing Pressures Effectively
Increase IPAP to
achieve:
Increase EPAP to:
Adequate tidal volume
Overcome obstruction in the
upper airways
Respiratory rate (RR)
< 25 bpm
Improve oxygenation
Decrease work of breathing
Reduction in PaCO2
Counterbalance PEEPi
Breath Cycle on Bilevel
Inhalation
Cycle
Trigger
Patient Flow
Exhalation
Delivered
Pressure
IPAP
EPAP
Pressure support (
P)
The Problem with Asynchrony
Asynchrony
Ineffective
Treatment
↑
Discomfort,
↓
Compliance
↑Accessory
Muscle Use
↑ WOB
How Can Inspiratory Time Controls
Help Increase Compliance?
Ti Max
IPAP
Ti Min
Rise
Time
EPAP
Breath cycle
0
Rise Time
Problem: Patient describes “Pressure is too STRONG!”
Solution: Increase rise time
Maximum Inspiratory Time
Problem: Patient requires longer expiratory time (i.e. COPD)
Solution: Best option – Shorten inspiratory time
Additional options – Select higher cycle sensitivity,
Select faster rise time
Minimum Inspiratory Time
Problem: Patient’s inspiratory effort is weak (i.e. restrictive disease)/can’t sustain
adequate inspiration
Solution: Best option – Increase/prolong Ti Min
Second option – Select lower cycle sensitivity
Trigger & Cycle Sensitivities
Adjustable Trigger Sensitivity
Adjustable Cycle Sensitivity
Patient
Flow
Patient
Flow
EPAP
Very High
Quick to trigger
2.4 L/min
High
More sensitive
4 L/min
Med
Default
6 L/min
Low
Less sensitive
10 L/min
Very Low
Slow to trigger
15 L/min
EPAP
Very High
Quick to cycle
50% of peak
High
More sensitive
35%
Med
Default
25%
Low
Less sensitive
15%
Very Low
Slow to cycle
8%
flow
Cycling for COPD Patients
Increased inflammation and mucus
Slower inspiratory flow rates
Delayed cycling to expiration
Less time for exhalation
Increased air trapping (PEEPi)
Increased trigger delay and trigger workload
Increased missed triggers
Increased work of breathing
COPD
Devices (E0470)
• Bilevel S
Diseases
• COPD
• Overlap syndrome
Tools to assist with ventilation and comfort
• TiControl
• Rise time
• Ti Max
• Ti Min
• Trigger sensitivity
• Cycle sensitivity
Synchrony Insight - Ti Min
Premature cycling
creates asynchrony
“However, premature cycling
may also have detrimental
effects on patient-ventilator
synchrony. Premature cycling
is simply when the ventilator
terminates the breath while
the patient requires a long
inspiratory period.”
Occurs in restrictive
patients
• Lungs physically
restricted
• Paralysis or muscles
deteriorated
Gentile, Respiratory Care, 2011
Restrictive Disease
Device (E0471)
• Bilevel ST
Diseases
• ALS
• Muscular dystrophy
Tools to assist with ventilation and comfort
• TiControl
• Rise time
• Ti Max
• Ti Min
• Trigger sensitivity
• Cycle sensitivity
Clinical Parameters
Subjective
•
•
•
•
•
•
Dyspnea
Comfort
Mental status
Ventilatory pattern
Accessory muscle use
Synchrony with VPAP
Objective
•
•
•
•
•
Vitals (RR, HR, BP)
Leak
Tidal volume
Oximetry
ABGs
Conclusion
•There are multiple benefits to using NIV,
particularly in patients with chronic hypoventilation
•There are additional features on some devices
that modify pressure waveforms and work to
improve bilevel tolerance