This document discusses non-invasive ventilation (NIV) for respiratory failure. It describes the types and causes of respiratory failure and lists selection criteria for NIV such as respiratory distress, abnormal blood gases, and respiratory acidosis. The benefits of NIV are reducing mechanical ventilation needs, ICU stay, and mortality. Goals of NIV are to reduce work of breathing, improve blood gases, and avoid intubation. Contraindications include poor mental status and hemodynamic instability. Modalities include high flow nasal cannula, bi-level positive airway pressure, and continuous positive airway pressure. Settings are titrated based on blood gases and comfort. Monitoring includes vital signs and blood gases to assess response.

1. Non Invasive Ventilation
When?
Why?
How?
Dr Jay Bhanushali
MD Pulmonary Medicine PGY 1

2. Respiratory Failure
• Respiratory failure is a syndrome in which the respiratory system fails in one or
both of its gas exchange functions: oxygenation and carbon dioxide elimination
• Failure of Pulmonary Gas Exchange to maintain normal Arterial O2 and CO2 levels
Type 1
Hypoxia Pao2 <60mmhg with Fio2 >60%
Type 2
Hypercarbia PaCO2 >45mmhg pH< 7.3

3. DIAPHRAGM
CHEST WALL
ACC RESPIRATORY MUSCLES
ALVEOLAR VENTILATION
DIFFUSION
PERFUSION

6. Selection Criteria for NIV
Acute Respiratory Failure
• Respiratory Distress
- Moderate to severe dypnea
- Use of accessory muscles
- Abdominal paradox
• Respiratory Rate
- >25/min with hypercapnia
- >30/min with hypoxia not corrected by 02 support
• pH< 7.35 and PaCO2 > 45mmhg Respiratory Acidosis
• PaO2< 60mmhg (spo2 90%) PaO2/FiO2 <200 moderate to severe hypoxia

7. Thoracic Restrictive/Cerebral Hypoventilation Diseases
-Fatigue, morning headache, hypersomnolence,nightmares, enuresis, dyspnea
(signs of CO2 retention)
-ABG PaCO2> 45mmhg
-Nocturnal SpO2 <90% for more than 5minutes sustained or 10%of total monitoring
time
-Symptoms and Signs of Cor Pulmonale seen with advance respiratory illness

8. Chronic Respiratory Failure
COPD
- Dyspnea, Fatigue, Somnolence
- ABG shows pH<7.35 PaCO2 > 55mmhg
- PaCO2 50-54mmHg with Oxygen Saturation <88% despite of O2 support
(Chronic Respiratory Acidosis)
Acute Cardiogenic Pulmonary Oedema
- CPAP is effective and should be considered in patients who fail to improve with medical
management alone

9. Benefits of NIV
• Decrease need of mechanical ventilation in appropriately selected patients
• Superior benefits in patients with Neuro muscular Disease, COPD, Pulmonary
oedema, post op respiratory insufficiency.
• Patient can communicate.
• Reduced length of ICU stay and reduced Mortality rates
• Complications related to Catheters
• Avoid invasive Ventilation related complications such as VAP, Upper Airway
trauma, post intubation tracheal stenosis
• Ceiling treatment in patients where invasive ventilation is not suitable /palliative
support
• Bridge treatment while patient awaiting lung transplant

10. Goals of NIV
• Reduce WOB
• Improve ABG
• Optimize patient comfort
• Avoid intubation
• Long term: Prolong survival, improve sleep, Maximize Quality of life, improve
Functional status

11. Contraindications
• NIV is not an alternative for Invasive Ventilation, decision for invasive ventilation
must not be delayed eg: Severe Asthma
• Poor GCS
• Severe hypoxia
• Facial trauma
• Bowel obstruction, upper GI surgery
• Hemodynamic Instability
• Uncooperative patient
• Cardio Respiratory Arrest

12. Problems with NIV
• Skin damage due to pressure ulcers in prolonged continuous use
• Air leak causing eye irritation.
• Claustrophobia, Aerophagia
• Requires continuous monitoring

13. Available Modalities of NIV
• High Flow Nasal Canula
- Heated humidified oxygen at high concentrations such that it flushes out a significant amount of
non oxygenated air from the upper airway. (Decreases Anatomical Dead Space and improves
alveolar
- Enhanced comfort, increased humidification of secretions to facilitate expectoration, washout of
nasopharyngeal dead space to improve efficiency of ventilation, provision of a small positive
airway pressure effect
- Similar efficacy rates compared to NIV Bi-level in Hypoxaemic non hypercarbic respiratory failure
patients in avoiding Intubation. Significant improvement in 90 day mortality compared to patients
who received other modalities.

14. Bi level PAP
• Positive pressure ventilation via a sealed face mask. It delivers 2 different airway
pressures while inspiration and expiration thus reducing the work of breathing.
• IPAP – EPAP = drive pressure (determinant of ventilation)
• Titrate IPAP upwards for adequate Vt and Minute ventilation
• BiPAP useful in COPD exacerbation, Weaning off Ventilator, Neuromuscular disorders

15. Continuous PAP
• Prevents alveolar collapse during expiration
• Initial setting to start : 5cm H20
• Titrated upwards with increments of 3cm H20 until hypoxia resolves or upto 10-
15cm H20
• CPAP can cause increase in CO2 retention if patient has weak expiratory effort.
• CPAP is useful in OSA and Pulmonary edema.

18. NIV Setting up
• Explaination and Preparation
- Explain the procedure
- Reassure
- Semi recurrent position 30-45 degrees
- propped up
• Mask Application
- Appropriate Size mask : Nasal Bridge to Chin
- Hold the mask over the patient’s face till patient is comfortable before tightening the straps
- Masks may be vented or nonvented; non-vented masks fixed tightly to the patient are utilized with a
device which has an exhalation valve, permitting release of carbon dioxide without (open)
exhalation ports.

19. • Pressurization
- Start with low settings
- IPAP 8cm H2o
- EPAP 4cm H20
- 02 at 2liters per minute
- Increase EPAP and IPAP in same proportion to maintain drive pressure
(minimum difference: 4cm of H20)
- Increase EPAP by 2 cm H20 till patient triggers the ventilator in all his inspiratory efforts
- Now start increasing IPAP further in increments of 2cm of H20 upto Maximum pressure that
can be tolerated by the patient without discomfort or 20mmhg whichever is higher
- Titrate IPAP to reach Goal of RR<25/min , Vt> 6ml/kg
- Check for leaks
- Increase o2 if hypoxia is persistent

20. • NEVER FORCE PATIENT TO USE THE DEVICE AGAINST THEIR WILL

21. Monitoring
• RR will reduce if NIV is effective (RR<25)
• Heart Rate
• Blood Pressure
• Abdominal Paradox
• Improvement of neurological status
• ABG to monitor adequate gas exchange @1hr and 4hr
• Continuous in 1st 24 hours
• Discontinue if no clinical improvement in 30 mins

23. BiPAP algorithm

30. Thank you
• References
-BTS guidelines
-ACS guidelines
-Oxford Handbook of respiratory medicine
-Washington manual of medical therapeutics
-Fishman’s principles of respiratory diseases
-images from internet