Non-Invasive Ventilation (NIV) is a respiratory support technique that delivers air or oxygen through a mask without the need for intubation. It is commonly used for conditions like chronic obstructive pulmonary disease (COPD), respiratory failure, and sleep apnea. NIV helps reduce work of breathing, improves gas exchange, and prevents complications associated with invasive ventilation, such as infections. There are two main types: continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BiPAP). NIV is preferred in many cases due to its comfort, ease of use, and ability to be administered in hospital and home settings for long-term management.

1. NIV INTERFACES AND
TROUBLESHOOTING
MODERATOR – Dr. SANDEEP MAHAJAN
BY – Dr. KRISHNAGANTHAN G

2. TYPES OF VENTILATORS
BILEVEL OR
PORTABLE VENTILATORS
CRITICAL CARE VENTILATORS

3. Bilevel ventilator Critical care ventilator
Circuit Single limb Dual limb
Type of ventilation Old models –only
Pressure targeted
ventilator
New models- volume
targeted
Volume and pressure
targeted ventilation
Advantage Portable, easy to use
and most home vent.
Predictable FiO2
delivery
Disadvantage Unpredictable FiO2
delivery, risk of
rebreathing due to
single limb, no
waveform display
Lack of leak
compensation, affects
the smooth
functioning
Comparison between different ventilators

4. NIV CIRCUITS

5. Interfaces
 Devices that connect ventilator and tubing to the face
 Types
- Nasal mask
- Nasal pillow
- Oral mask
- Oro – nasal mask/ Face mask
- Full face mask
- Helmet
 Interfaces should be comfortable, offer a good seal, minimizes
leak and limit dead space.

6. TYPES OF MASKS

8. NASAL MASKS
 Covers only nose.
 Advantages
- Easy to fit
- Less feeling of claustrophobia
- Low risk of aspiration
- Patient can cough and clear secretions
- Maintains ability to speak and eat
- Less mechanical dead space
 Disadvantages
- Mouth leaks
- Not possible with nasal obstruction
- Ulceration over nose bridges
- Oral dryness
- Nasal congestion, irritation, dryness

9. NASAL PILLOWS
 Advantages
 Allows
 speaking
 Drinking
 Coughing
 Absence of nasal or facial damages
 Disadvantages
 -Air leaks
 -Nasal irritation
 -Hypersalivation

10. FACE MASKS (ORO-NASAL
MASKS)
 Advantages
 Reduces air leakage through the mouth
 Easier to fit
 Preferred masks in case of mouth breathing
 and acute respiratory failure
 Disadvantages
 Increased risk of vomiting, aspiration
 Increased risk of asphyxia
 Claustrophobia
 Facial skin irritation
 Nasal, face pressure sores
 One cannot eat, speak or expectorate secretions

11. FULL FACE MASK

12. ORAL MASK
 DISADVANTAGES
 Vomiting
 Hypersalivation
 Gastric distension
 Talking and eating difficult
 Pressure loss through the nose
 USED IN NERUOMUSCULAR DISORDERS

13. NIV HELMET

14. ADVANTAGES
 Ability to deliver higher PEEP levels for prolonged durations because
of minimal leak
 No skin lesions or pressure ulcers due to the helmet’s lack of contact
with the face
 Less resistance to flow
 Can be applied regardless of the facial contour, facial trauma or
edentulism
 Allows coughing
 Little cooperation required
 Better comfort
 Less interference with speech and less risk of aerosol dispersion

15. DISADVANTAGES
 CO2 rebreathing
 Can not measure tidal volumes
 Asynchronies – Trigger delay, slow pressurization
 Noise due to air flow
 Edema of the limbs
 Axillary skin damage

16. CHOICE OF MASK
 In ARF, patients often start mouth breathing to bypass the higher
resistance of the nose. This can result in mouth breathing and
compromise the efficacy of ventilation if nasal masks are used.
 All interfaces can be used to provide NIV successfully, but in the acute
setting interfaces covering the mouth and nose are advantageous.
 Try switching to a smaller interface once the patient is more stable.
 There is currently no strong scientific evidence that one type of
mask is necessarily or consistently better than others in terms of
clinical efficiency.

17. SELECTING CORRECT INTERFACE
SIZE
 The nasal mask should fit just above the junction of the nasal
bone and cartilage, directly at the sides of the both nares and
just below the nose above the upper lip.
 The oronasal mask should fit from just above the junction of
the nasal bone and cartilage to just below the lower lip

21. TROUBLESHOOTING DURING
NIV

22. Eye irritation
Nasal dryness/
congestion
Dry mouth
Aerophagia
Air leaks
Pressure sores
Claustrophobia
MASKS RELATED
PROBLEMS

23. REDUCING PRESSURE ULCERS
Recommendations(ISCCM) – Oro-nasal mask is the most preferred interface for NIV for
acute respiratory failure.
-All interface should be made of soft material. Cushioning of skin in contact with the interface
may be done with hydrocolloids, foam pad or transparent dressing.
-All patients on NIV should undergo periodic skin assessment of pressure points, every 4-6
hourly. (UPP)

24. Two finger rule
Skin assessment
Pressure points

25. DRYNESS
 Nasal/oral dryness and nasal congestion usually indicates air leakage
through the mouth, which results in the loss of the nasal mucosal capacity
to heat and to humidify inspired air.
 Increased nasal congestion and nasal resistance reduced tidal volume and
causes patient discomfort
 Solutions – Heated humidification, reducing the leak, using oronasal masks

26. Humidification
Methods
• Heat Moisture
exchanger
(HME) and
heated
humidifiers are
used for providing
humidification in
patients on NIV.
Disadvantages
• Use of HME
increases the
WOB, rebreathing
and PaCO2 levels
• Risks associated
with HME –
frequent blockage
with moist
secretions and
added resistance
to breathing.
**Recommendatio
n
• Humidification is
not routinely
required in
patients on NIV.
However, patients
who complain of
dryness of
respiratory tract,
or thick tenacious
secretions,heated
humidification or
HME may be
considered.

27. AEROPHAGIA
 During NIV, the ventilation volume distributes between lungs and stomach
depending on respiratory system resistance and lower oesophageal
sphincter pressure (20-25 cm H2O).
 Predisposing factors – Large tidal volumes, high pressure setting, high
airway resistance, low respiratory system compliance, short inspiratory
time.
 Gastric distension compresses the lungs, thereby decreasing lung
compliance and requiring higher airway ventilation pressure. The latter is
also associated with increased risk of gastric distension, thus generating a
vicious cycle.

28. CO2 REBREATHING
 Leak port in the mask rather than in the circuit
 Minimum PEEP of 4cm of H2O in single limb circuit with passive
exhalation valve.
 Using active exhalation valve instead of passive exhalation valve
 Increase expiratory time, ensure adequate tidal volumes and
reduce RR
 Maintain high gas flow rates (40-60 L/min) in helmet masks.

30. AIR LEAKS
 INTENTIONAL LEAKS/ CALIBRATED LEAKS

31. UNINTENTIONAL LEAKS

32. INTERVENTIONS TO REDUCE AIR
LEAKS
 Ensure proper interface type, size and securing system
 Hydrogel or foam seal, lip seal or mouth taping
 A chin strap can be used to prevent mouth breathing in patients
using nasal masks
 Decreasing pressure support
 Tube adapters for NG tube
 Leaks are minimal with helmet mask

33. CAUSES OF NIV FAILURE

34. PREDICTORS OF NIV FAILURE
Various studies have shown the following criteria for NIV failure:129,130
 High severity score of illness (APACHE II, SAPS II, SOFA scores)
 Older age
 Failure to improve after 1 hour on NIV
 Multiorgan involvement
 Premorbid status (inability to perform self care)
 Mean pH < 7.25, mean PaCO2 >= 75 mmHg after 2 hours of NIV initiation,
in patients with hypercapnic failure.
 Difficult to identify the etiology of acute respiratory failure
 ARDS / pneumonia as the etiology
 PaO2/ FiO2 < 150 mmHg
 Higher Tidal volume generation.

35. PREDICTORS OF NIV FAILURE HACOR
SCORE

36. INFECTION TRANSMISSION WITH NIV
Apart from personal protective equipment (N95 mask, gown, gloves,
eye protection) and hand hygiene, it is recommended that following
precautions to be taken when using NIV on a patient with infectious
disease:
 Minimize leaks in the circuit.
 Non-vented face mask, or a helmet – with the best fit to the facial
contour.
 Secure the mask, prior to turning on the ventilator. Turn off the
ventilator before removing the mask.
 A viral/bacterial filter (to filter particles 0.3 mm in size) at the outlet of
the ventilator and also at the expiratory side of the circuit.
 Complete decontamination of the ventilator before use in other
patients.

37. WEANING FROM NIV
Clinical criteria to be met by patients before Weaning is attempted.
Measure Character
1. Arterial pH ≥ 7.35
2. SpO2 > 90%
3. Respiratory Rate ≤ 25 / min
4. Heart rate ≤ 120 / min
5. Systolic blood pressure ≥ 90 mmHg
6. Signs of respiratory distress No agitation, diaphoresis,
anxiety

38.  It is recommended that weaning from NIV may be done by a
standardized protocol driven approach.
 Weaning strategies
Varied Strategies for weaning from NIV has been described:
 Stepwise reduction in NIV duration.
 Stepwise reduction in NIV pressure support.
 Immediate withdrawal of NIV after stabilization.

39. STEPWISE REDUCTION IN NIV DURATION
 Progressively reducing the duration of NIV over a period of 3-4 days
 Initially weaning should be carried during daytime, with overnight
ventilation
 The daytime weaning can be divided into periods of 3 hours each and
can be performed as follows –
 Day 1: NIV 3 hours ON, I hour OFF (except during night period)
 Day 2: NIV 3 hours ON, 2 hours OFF (except during night period)
and
 Day 3 NIV can be used during the night period
 NIV may be discontinued on Day 4 unless continuation is clinically

40. STEPWISE REDUCTION IN NIV PRESSURE SUPPORT
 gradual reduction (2-3cms of H20) of IPAP and EPAP over a
period of 6-8hrs and removing NIV once the patient tolerates
IPAP of 6-8cms of H2O and EPAP of 4-5cms of H2O.
IMMEDIATE WITHDRAWAL OF NIV
 This strategy involves immediate cessation of NIV once the
patient stabilizes.
 Though it has potential advantage of shortening the duration of
weaning process, the rates of failure of weaning and reinstitution
of NIV can be higher.

41. DISCHARGE
 For patients needing long term home NIV, an
individualized plan with a plan matrix should be
organized, involving all concerned parties, with clearly
defined roles.
 Education and training of the care giver, round the clock
technical support, are the minimum pre-requisites before
planning to discharge the patient on NIV.