This presentation covers all aspects of NIV in acute settings

2. NIV in Acute Settings
Gamal Rabie Agmy ,MD ,FCCP
Professor of Chest Diseases, Assiut University

5. Rationale for ventilatory assistance
 Respiratoryload
 Respiratorymuscles
capacity
Alveolar hypoventilation
 PaO2 and  PaCO2
Abnormal
ventilatorydrive

6. Mechanical ventilation unloads the
respiratory muscles
Respiratory load Respiratory muscles
Mechanical
ventilation

12. Severe
Mild
To
moderate
Not
established
COPD
exacerbation
Post-extubation
COPD
exacerbation
Hypoxemic
Post-extubation
COPD
Exacerbation
Hypoxemic
Weaning
DNI order
Meaning of
NIV use
ARF
Severity
TO PREVENT
TO AVOID
ETI
ALTERNATIVE
to ETI

13. 300 250 200 150 100 50
Low Tidal Volume Ventilation
Higher PEEP
HFO
Prone Positioning
ECMO
Low – ModeratePEEP
Neuromuscular
Blockade
PaO2/FiO2
Increasing Severity of Lung Injury
Mild ARDS Moderate ARDS Severe ARDS
IncreasingIntensityofIntervention
NIV
ECCO2-R
iNO
The case of ARDS

14. Ventilators for NIV: Not all are
useful in each indication

15. Standard interfaces
Facial masks
advantages:
– sufficient ventilation also
during mouth breathing
– sufficient ventilation in patients
with limited co-operation
disadvantages:
– coughing is difficult
– skin lesions (bridge of the nose)

16. Nasal masks
advantages:
– better comfort
– good seal
– coughing is possible
– communication is possible
disadvantages:
– effective in nose breathing only
– good co-operation is necessary
Standard interfaces

17. Nasal prong/nasal pillow systems
for patients with
claustrophobia
for patients with allergies
against straps
for low to moderate
pressures only
(< 20 cmH2O)
Standard interfaces

18. total-face masks
• Safe interface for acute respiratory
insufficiency with high pressures
• well tolerated by the patients
Standard interfaces

19. helmet
• well tolerated by the patient
• no direct contact to the skin of
the face
• large dead space
• may influence the triggering of
the patient; use with CPAP
• very noisy
Standard interfaces

20. mouthpieces
• simple and cheap
• short-interval alternative
interface for long-term
ventilated patients
Custom-made masks
• for long-term ventilation
• if standard masks are not
tolerated
Standard interfaces

21. Physiologic evaluation of three
different interfaces
cohort: 26 stable patients with hypercapnic COPD or interstitial lung disease.
intervention: three 30 minute tests in two ventilatory modes with
facial mask / nasal mask / nasal prongs
Conclusions: NIPPV was effective with all interfaces.
patients„ tolerance: nasal mask > facial mask or nasal prongs
pCO2 reduction: facial mask or nasal prongs > nasal mask
Navalesi P et al. Crit Care Med 2000;28:2139-2140

23. The respiratory System
Lungs Respiratory Pump
Pulmonary
Failure
• PaO2
• PaCO2 N/
Ventilatory Failure
• PaO2
• PaCO2
Hypoxic
Respiratory Failure
Hypercapnic
Respiratory Failure

24. Lungs
Respiratory
Pump
Pulmonary Failure
• PaO2
• PaCO2 N/
Ventilatory Failure
• PaO2
• PaCO2
Hypoxic
Respiratory Failure
Hypercapnic
Respiratory Failure
The respiratory System

25. CNS
breathing center
1. motor neuron
PNS
2. motor neuron
Motor endplate
neuromuscular junction
Inspiratory
respiratory muscles
Rib cage
Pleural pressure
Alveolar pressure
INSPIRATION
Respiratory
pump

26. CNS
breathing center
1. motor neuron
PNS
2. motor neuron
Motor endplate
neuromuscular junction
Inspiratory
respiratory muscles
Rib cage
Pleural pressure
Alveolar pressure
INSPIRATION
Respiratory drive disturbances
Neuromuscular disorders
ALS, Myasthenia gravis,
Duchenne Muscular Dystrophy,
myopathy
Mechanical disturbances
hyperinflation,
rib cage deformities
Thoracic instability
Reduced compliance
Increased airway resistance

27. Jolley CJ and Moxham J. Eur Respir Rev 2009;
18:112,1-14

28. • Diaphragm flattening
• Diaphragm
prestretching
• Systemic involvement
• Inflammation
• Steroids
• VIDD
• Co-morbidities
• Heart failure
• Pulmonary
hypertension
• Diabetes
• Shortening of
inspiration
• Airway obstruction
• Dynamic hyperinflation
• Intrinsic PEEP
• Thoracic prestretching
• Increased ventilatory
demand
• pulmonary failure
• anemia
• heart failure
COPD
Jolley CJ and Moxham J.
Eur Respir Rev 2009;
18:112,1-14

29. Evans TW. Intensive Care Med 2001; 27:166-178

30. Mechanical ventilation
Noninvasive
“NIV”
invasive

31. NIV
success
within
1-2 hours ?
Improveme
nt
for several
days ?
Weaning
from NIV
Spontaneou
s breathing
NIV Start
NIV in acute hypercapnic failure
- successful intervention

32. Rationale for
Non-invasive Ventilation (NIV)
to improve respiratory function and symptoms
• blood gases
• dyspnea
• respiratory rate
to avoid intubation and related complications
• ventilator-associated pneumonia (VAP)
- i.e. tube associated pneumonia
• local complications related to tube (early & late)
• complications related to catheterization
• tracheostomy and weaning failure
to improve outcome
• to reduce length of ICU and hospital stay
• mortality

33. NIV: Further advantages
Intermittent application
Improved clearance of secretion
Communication
Swallowing
No or mild sedation

34. NIV = MECHANICAL VENTILATION !
RATIONALE :
NIV improves oxygenation
Antonelli et al. NEJM 1998; 339:429-35
NIV increases VT and unloads diaphragm
Brochard et al. Am Rev Respir Dis 1989; 139:513-2

35. NIV decreases nosocomial infections
Girou E, Schortgen F, Delclaux C, et al. JAMA 2000, 284, 2361-7

37. Level Pathophysiology
High
(several RCT)
COPD Exacerbation
Acutecardiogenicfailure
Weaning & Postextubation faulire in COPD
Medium Asthma bronchiale
Cysticfibrosis
Avoiding extubation failure
Do-not-intubateorder
Low ARDS (Acuterespiratorydistress syndrome)
NIV in acute hypercapnic failure
Level of evidence

38. NIV IN ACUTE HYPERCAPNIC FAILURE
CAUSED BY COPD

39. MORTALITY OF PATIENTS WITH COPD
REQUIRING INVASIVE MECHANICAL
VENTILATION FOR ACUTE RESPIRATORY
FAILURE
study year In-hospital Mortality, %
Knaus 1989 42
Stauffer et al 1993 33
Rieves et al 1993 43
Seneff et al 1995 32
Brochard et al 1995 29
Corrado et al 1998 27
Hill et al 1998 49

40. NIV bei AE-COPD
Behandlung von 8 Patienten,
um 1 Leben zu retten
BMJ 2003, 25; 326: 185

41. Lightowler JV. et al. BMJ 2003; 326:185-
• NIV prevents intubation
(NNT = 5)
• NIV reduces mortality
(NNT = 8)
NNT = number needed to treat

42. META-ANALYSIS (N=8)
• NIV resulted in
– decreased mortality (RR 0.41; 95% CI 0.26,
0.64),
– decreased need for ETI (RR 0.42; 95%CI
0.31, 0.59)
• Greater improvements within 1 hour in
– pH (WMD 0.03; 95%CI 0.02, 0.04),
– PaCO2 (WMD -0.40 kPa; 95%CI -0.78, -
0.03),
– RR (WMD –3.08 bpm; 95%CI –4.26, -1.89).
• Complications associated with treatment (RR
0.32; 95%CI 0.18, 0.56) and length of hospital
stay were also reduced with NPPV (WMD –
3.24 days; 95%CI –4.42, -2.06)
Lightowler, Elliott, Wedzicha & Ram BMJ 2003; 326:185

43. Lightowler JV. et al. BMJ 2003; 326:185-
189
Conclusions
NIV should be the first line intervention in addition to
usual medical care to manage respiratory failure
secondary to an acute exacerbation of chronic
obstructive pulmonary disease in all suitable
patients.
NIV should be tried early in the course of respiratory
failure and before severe acidosis,
to reduce mortality, avoid endotracheal intubation,
and decrease treatment failure.
first
line
pH:
7.20–7,35
Improves
outcome
NIV:

44. Confalonieri, et al. AJRCCM 1999; 160: 1585-1591
• 56 Pats with Pneumonia
• 23 COPD - 33 non-COPD
• Prospektive RCT:
- PSV + Standard-treatment
- O2 + Standard-treatment

45. Am J Respir Crit Care Med 1999;160:1585-15
*
PaCO2 [mmHg]
Intubation [%]
ICU – length of stay [d]
2-Mo-moratliy [%]
NIV Standard
73
0
<1
11
68
55
8
63
32
38
3
43
34
47
5
33
NIV Standard
*p < 0.05
COPD (n = 23) Non-COPD (n = 33)
* *
*
* *

46. NIV in weaning: Early extubation
NIV in the weaning of patients with respiratory
failure due to COPD

47. NIV in weaning: Early extubation
24-36 hrs of PSV
50 patients
2 hr T-piece trial
failed
Randomized
NIV to 25 br/min, ABGs
6 by 2-4 cmH20/day
SBT 2 x/day
IPSV to 25 br/min, ABGs
“gradually” 6
CPAP or T piece, 2 x/day
Nava et al. Ann Intern Med 1998;128:721-8
NIV in the weaning of patients with respiratory failure due to
COPD

48. Invasive MV
NIV
Weaning success  with NIV
NIV in the weaning of patients with ARF due to COPD
Nava et al. Ann Intern Med. 1998;128:721-8
NIV in weaning: Early extubation

49. NIV to wean from respirator in stable COPD
Nava et al. Ann Intern Med 1998;128:721-8
Invasive Non-invasive
MV days 17 10*
ICU days 24 15*
60d wean success 68% 88% *
60 d survival 72% 92% *
Pneumonia 25% 0% *
wean failure: death from MV and reintubation in 72h

50. NIV
success
within
1-2 hours ?
Improveme
nt
for several
days ?
Weaning
from NIV
Spontaneou
s breathing
NIV Start
NIV IN ACUTE HYPERCAPNIA
Early Failure
Early NIV-failure
Intubation

51. Ineffective
ventilation
Failing
synchrony
NIV-failure
NIV IN ACUTE HYPERCAPNIA
Failure

52. Moretti M. et al. Thorax 2000;55:819-82
N= 137
Patients with
NIV success*
*NIV > 24 Std.
N= 31
Patients with late
NIV-failure after
primary NIV-success*
23%
Acute exacerbation of COPD
after 48 hours
Mortality IMV 53%, continuing NIV 92%
(NIV group pH 7.1 IMV 7.29)
Late failure predicted by low ADL scores,
pH and co-morbidity at admission

53. Moretti M. et al. Thorax 2000;55:819-8
Late NIV failure:
• lower pH at admission
• higher complication rates
• ICU-Mortality
• 92% when NIV was continued
• 53% when intubation was performe

54. Invasive MV instead of NIV
- in terms of clinical issues
Invasive MV
Lavage
bei Hypersecretion
Unloading
respir. muscles
Improvement of
neurophysiologic
situation
Aim: Extubation after 2-3 day
- with/without consecutive NIV
Massive hypersecretion Massive Load
on respir. muscles
Neurophysiologic
disaster

56. NIV im Koma

59. Thoraco-Restriction & Neuromuscular
disease
Obesity
Palliation
Special indication for NIV in acute hypercapnia
in Non-COPD patients

60. Flandreau G et al. Management and long-term outcome of patients with chronic
neuromuscular disease admitted to the intensive care unit for acute respiratory failure:
a single-center retrospective study. Respir Care 2011; 56: 953 – 960
Special indication for NIV in acute hypercapnia
Neuromuscular disease

61. Intermittent NIV
to recondition
respiratory
muscles
Bronchoscopy
Physiotherapy
NIV & aggressive secretion management

62. DNI: Do not intubate
• Aims
–Reduced Dyspnea
–Improved quality of
life („Comfort“)
–Buy time
INDICATION: NIV IN PALLIATION

63. DYSPNEA INDEX
0
1
2
3
4
5
6
7
8
9
10
ADMISSION NIV 1 hr
*

65. THE RATIONALE

66. LV failure
Pulmonary
edema

Pulmonary
compliance
 Airway
resistance
 Negative
Intrathoracic
Pressure
Swing

Work of
breathing
 CO
 PaO2
Respiratory
muscle
fatigue
 DaO2
+
 PaCO2

67. LV failure
Pulmonary
edema
 Pulmonary
compliance
 Airway
resistance
 Negative
Intrathoracic
Pressure
Swing
 LV
transmural
pressure
 O2
Cost of
breathing
 LV afterload
+

68. Rasen et al: Chest 1985; 87: 158-162
Negative intrathoracic pressure swings during CPE
Pes
(cmH20)
0
-20

69. IntraThoracicPressure
and
LV function
AO
LV
ITP  effort =  ITP = Ptm

 LV afterload
100
-20
Ptm = 100-(-20) = 120

70. CPAP IN CPE
Rasen et al: Chest 1985; 87: 158-162
Pes
(cmH20)
0
-20
Spontaneous breathing CPAP 15 cmH20

71. IntraThoracicPressure
and
LV function
AO
LV
ITP  effort =  ITP =  Ptm

 LV afterload
100
-5
Ptm = 100-(-5) = 105

72. Rationale of positive pressure
ventilation in CPE
Positive Pressure
 ITP  FRC
Pre-load
 Venous return
 LVafterload
 PTM
 PaO2  WOB
 Cardiac performance
 pulmonary congestion

73. Targets of ventilation in
cardiogenic pulmonary oedema
• improvement of oxygenation
• improvement of respiratory acidosis
• reduction of work of breathing
• improvement of cardiac performance
• reduction of patient’s distress

74. NIV and obesity: in the acute
setting

75. OHS: Definition
- Obesity (BMI 30 kg/m2)
- Hypercapnia (PaCO2  45 mmHg)
- Sleep-disordered breathing
Thomas Nast, The Pickwick Papers

76. OHS: Clinical Presentation
 Middle-aged
 2:1 male-to-female
 Extremely obese
 Significant sleep-disordered breathing
(fatigue, hypersomnolence, snoring, AM
headache)

78. Needs confirmation

81. Conclusions
Multiple organ failure and pneumonia were the main factors associated with
NIV failure and death in morbidly obese patients in hypoxic ARF. On the
opposite, NIV was constantly successful and could be safely pushed further in
case of severe hypercapnic acute respiratory decompensation of OHS.

82. Potential goals of noninvasive ventilation (NIV) in severe acute asthma.
Dean R Hess Respir Care 2013;58:950-972
(c) 2012 by Daedalus Enterprises,Inc.

83. Bronchoscope inserted through the swivel adaptor of a face mask for noninvasive ventilation.
Dean R Hess Respir Care 2013;58:950-972
(c) 2012 by Daedalus Enterprises,Inc.

84. Monitoring of NIV in the acute setting

85. AIMS
Goals of monitoring
Types of monitoring
Setting for monitoring
Goals of monitoring
Types of monitoring
Setting for monitoring

86. Why we need Monitoring during MV?
 To Assess the effectiveness of MV in
-Unloading respiratory muscles
-Correcting gas exchange abnormalities
-Improving alveolar ventilation
 To Identify complications during MV
-correlated with MV
-correlated with ARF
 To predict patient’s outcome in terms of
-Survival
-Dependence on MV
-Autonomy in performing ADLs

87. Is Monitoring less important during
NIV? Airways not protected
 Presence of leaks
 Lack of sedation
 Use outside ICU

88. Which goals of Monitoring during NIV?
 To Assess the effectiveness of NIV in
-Unloading respiratory muscles
-Correcting gas exchange abnormalities
-Improving alveolar ventilation
-Patient-ventilatory synchrony
 To Identify complications during NIV
-correlated with NIV
-correlated with ARF
 To predict patient’s outcome in terms of
- NIV failure (i.e. Need of ETI)
-Survival
-Dependence on MV
-Autonomy in performing ADLs
 To Assess the effectiveness of NIV in
-Unloading respiratory muscles
-Correcting gas exchange abnormalities
-Improving alveolar ventilation
-Patient-ventilatory synchrony
 To Identify complications during NIV
-correlated with NIV
-correlated with ARF
 To predict patient’s outcome in terms of
- NIV failure (i.e. Need of ETI)
-Survival
-Dependence on MV
-Autonomy in performing ADLs

89. AIMS
Goals of monitoring
Types of monitoring
Setting for monitoring

90. Availability of
ETI
• in case of NIV
failure
Ventilatory
Monitoring
• Respiratory pattern
• Pt-vent interaction

91. TYPES OF
MONITORING
CLINICAL
MONITORING
PHYSIOLOGI
C
MONITORING
LABORATORY
MONITORING
NIV
MONITORING

92. TYPES OF
MONITORING
CLINICAL
MONITORING
PHYSIOLOGIC
MONITORING
LABORATORY
MONITORING
NIV
MONITORING

93. HOOVER
SIGN
ACCESSORY RESPIRATORY
MUSCLESPARADOXYCAL BREATHING
How is the patient
breathing?

94. Bott J. et al. Lancet 1993; 341:1555-7
Monitoring Dyspnea
NIV
SMT
VAS

95. CarlucciA. et al Am J Respir Crit Care Med
Patient’s Cooperation and
Sensorium
NIV
OUTCOME

96. Hypercapnic
Encephalopathy
Scala R.

97. Levels of Hypercapnic
Encephalopathy and NIV failure
KELLY=1 KELLY=2 KELLY=3 KELLY>3
Scala R. et al, Chest. 2005;128(3):1657-66

98. Agitation and sedation

99. Roche-Campo F et al., Crit Care Med 2010
Delirium

100. TYPES OF
MONITORING
CLINICAL
MONITORING
PHYSIOLOGIC
MONITORING
LABORATOR
Y
MONITORING
NIV
MONITORING

101. TECHNICAL LIMITATIONS
• Poor peripheral perfusion
• Movements artifacts
• Haemoglobinopathies
• Nail polish
• Hyperbilirubinemia (> 15 mg/dL)
Pulse-oximetry
CONTINUOUSMONITORING OF OXYGENATION
DURINGNIV
AND SPONTANEOUS BRETAHING
PHYSIOLOGICAL LIMITATIONS
• Variable PaO2/SpO2 correlation
• Lack of information on PaCO2

102. PLATEAU
REGION
STEEP
REGIO
N

103. ETCO2
Expiratory Capnography
LIMITED APPLICATION in
NIV
-Leaks
-Additional dead space (Interface)
-Variable Circuit
-Variable Expiratory system (single-
limb)

104. 46 pts with ARF under NIV (Range PaCO2: 33-91 mmHg) -TCM4: trunk
PtCO2 sensor
Under-estimation of PaCO2 in pts
with greater hypercapnia (PaCO>60
mmHg)

105. TREND OF TC-PCO2
Kocher S et al, J Clin Monitor Comput 2004
Domingo Ch et al, Arch Bronchoneumol 2006

106. Arterial blood gas-analysis
Gold standard
Oxygenation status (PaO2/FiO2
ratio)
 Ventilatory status (PaCO2)
 Metabolic status (pH/HCO3)
Co-oximetry (COHb)
Weak points:
-Invasive
procedure
-Spot data
Prognostic
value
-Baseline
-After 1-2 hrs
-Late failure

107. Antonelli M. et al. Crit Care Med 2007;35(1):18-25
PaO2/FiO2 during NIV in
ARDS

108. pH at baseline in COPD exacerbations
Nava S. et al., Intensive Care Med 2006; 32(3):361-70.


109. Respiratory Rate and NIV
failure
Confalonieri M et al.

110. How to assess RR on spont
breathing?
Clinical
evaluation
Impedenzometry
Capnography
Pnemotacograph

111. Schettino G. et al., Crit Care Med 2008;36(2):441-7
Reasons for NIV failure
Cardiovascular
monitoring
(ECG, NIBP, PR)

112. Helpful in
Understanding the causes of nocturnal desaturations
Re-Setting the ventilator
Janssens JP et al. Thorax 2011;66(5):438-45
Sleep monitoring

113. TYPES OF
MONITORING
CLINICAL
MONITORING
PHYSIOLOGIC
MONITORING
LABORATORY
MONITORING
NIV
MONITORING

114. X RAY

115. ULTRASONOGRAPHY
CT
SCINTIGRAPHY

116. BIOCHEMISTRY
Pro-BNP
CRP
Procalcitonin
Miocardial markers
Electrolites
………

117. FLUID
BALANCE

118. TYPES OF
MONITORING
CLINICAL
MONITORING
PHYSIOLOGI
C
MONITORING
LABORATOR
Y
MONITORING
NIV
MONITORING

119. Am J Respir Crit Care Med. 2001
Feb;163(2):540-77
Almost all the side effects of NIV are due to
problems with interfaces

120. Types of Leaks
Intentionalleaks

121. Monitor the tightness of the
mask

122. LOOK FOR A BALANCE
BETWEEN
LEAKS AND COMFORT

123. Ventilator monitoring:
numeric data and curves

124. Berg KM et al., Respir Care 2012;57:1548-54
Respiratory pattern and NIV
Failure
INTUBATION
aRSBI= RR/exp- TV during NIV
Exp TV = pt TV
HOW COULD WE MONITOR exp-TV and RR DURING NIV?

125. Monitoring: ready access to ETI and
CPR

126. Non-invasive ventilation
failure in the acute patient

127. What is the NIV failure?
Need for tracheal intubation and death
When does it happen?
 Immediate: < 1 hr
 Early : 1- 48 hrs
 Late: > 48hrs

128. NIV FAILURE (%)
Immediate Early Late
17
68
15

129. How to Reduce Air Leaks During NIV
 Proper interface type and
size
 Proper securing system
 Mask-support ring
 Comfort flaps
 Tube adapter
 Hydrogel or foam seals
 Chin strap
 Lips seal or mouth taping
Nava S et al. Respiratory Care 2009; 54: 71-82
Mask occlusion pressure = Pmask-fit – Paw

131. How to Reduce the Risk of Skin
Damage During NIV
 Proper harness and tightening
 Skin and mask hygiene
ava S et al. Respiratory Care 2009;54:71-82
 Nasal-forehead spacer
• To reduce the pressure on the bridge of the
nose
 Forehead and skin pads
• To obtain the most comfortable position
 Cushioning system between mask prong and
forehead
 Remove patient’s dentures when making
impression for moulded mask
 In home care, replace the mask according
to the patient’s daily use

132. Skin ulcers

133. Risk for skin lesion

134. A possible solution: the total face mask

135. Another solution:
the “Helmet”
Courtesy of Dr. Stefano Nava (Bologna, Italy)

136. • Not always appear
where expected!!!
Pressure ulcer

137. Predictors of failure: NIV for hypercapnic
respiratory failure
 Advanced age
 Higher acuity of illness (APACHE score)
 Uncooperative
 Poor neurological score
 Unable to coordinate breathing with ventilator
 Large air leaks
 Edentulous
 Tachypnoea (>35/min)
 Acidaemia (pH <7.18)
 Failure to improve pH, heart and respiratory rates or
Glasgow Coma Score within the first 2 hours
Soo Hoo et al. Crit Care Med 1994; 22: 1253–61
Ambrosino et al. Thorax 1995; 50: 755–7
Confalonieri et al. Eur Respir J 2005; 25: 348–55

138. Non-COPD conditions:
 Pneumonia (n=37)
 Neuromusculoskeletal disorders (n=11)
 Pulmonary oedema (n=9)
 Bronchiectasis (n=5)
 Sepsis (n=3)
 Asthma (n=3)

139. Outcomes of NIV in non-COPD patients by
specific diagnosis

140. At admission
• 1,033 consecutive patients
•Success rate: 797 (77%)

141. After 2 h of NIV

142. • Eight ICUs
• n=354:
• Success: 246
• Failure: 108
Other predictors of
failure:
 Higher SAPS
 Lower PaO2/FIO2 and
failure to improve
 Low pH
 Older age
 Septic shock, MOF

143. Common reasons for NIV failure
 Environmental/caregiver team
factors
• Lack of skilled, experienced caregiver
team
• Poor patient selection
• Lack of adequate monitoring
Selection guidelines for NIV in the acute setting
 Appropriate diagnosis with potential reversibility (COPD,
congestive heart failure, …..)
 Establish need for ventilatory assistance:
• Moderate to severe respiratory distress
and
• Tachypnoea (>24/min for COPD, >30/min for CHF)
• Accessory muscle use or abdominal paradox motion
• Blood gas derangement: pH <7.35, PaCO2 >45, or
PaO2/FiO2 <300

144. Contraindications of NIV
 Respiratory or cardiac arrest
 Too unstable patient:
• Shock
• Myocardial infarction
requiring intervention
• Uncontrolled ischemia or
arrhythmias
• Uncontrolled upper GI bleed
• Non-evacuated pneumothorax
 Unable to protect airway*
• Excessive secretions
• Poor cough
• Impaired swallowing
*Relative contraindications?
 Aspiration risk*
• Distended bowel; obstruction
or ileus
• Frequent vomiting
 Uncooperative or agitated*
 Unable to fit mask
 Recent upper airway or
oesophageal surgery
 Multiple organ system failure
(>2)

145. Common reasons for NIV failure
 Patient-related factors
• Intolerance
• Mask problems:
• Discomfort
• Poor fit
• Skin ulceration
• Claustrophobia
• Agitation
• Excessive secretions, inability to protect
airway
• Progression of underlying disease

146. Approach to the agitated/intolerant patient
using NIV

147. Common reasons for NIV failure
 Technical factors
• Inadequate equipment
• Failure to ventilate
• Failure to oxygenate
• Patient–ventilatorasynchrony
• Air leaks

148. Successful NIV: Important
factors
 More likely with a good team
• A skilled, experienced staff helps to optimize outcomes
 The underlying disease is an important
determinant
• Selecting appropriate patients and monitoring them
closely
 Severity at presentation
 Change in physiology after a short period of NIV
• If failure to ventilate or oxygenate, rapidly assess for
reversible contributing factors
• Be prepared to intubate without undue delay if rapid
reversal cannot be achieved (particularly in hypoxemic
patients)
 A systematic approach to troubleshooting can help