Non-invasive ventilation (NIV) delivers ventilatory support through a mask without using an invasive tracheal tube. The document discusses the history and development of NIV, benefits in pediatric patients, indications, contraindications, modes, and key points for successful use of NIV. It provides details on using NIV to treat acute hypoxemic and chronic hypercapnic respiratory failures in children. Close monitoring and criteria for escalating to invasive ventilation if NIV fails are also reviewed.
3. What is NIV
• Non-invasive ventilation (NIV) refers to the provision of
ventilatory support through the patient's upper airway
using a mask or similar device.
• This technique is distinguished from those which bypass
the upper airway with a tracheal tube, laryngeal mask, or
tracheostomy.
Thorax 2002;57:192-211 doi:10.1136/thorax.57.3.192
BTS guideline
Non-invasive ventilation in acute respiratory failure
4/27/2017 3
4. History
• Reports dating from the mid 1700s document a bellows-
type device being the most commonly used form of
respiratory assistance.
• Negative-pressure tank-type ventilators came into use in
the next century, with a prototype developed by Dalziel in
1832.
• Ventilators with the general principle of enclosing the
thorax, creating negative pressure to passively expand
the chest wall and lungs. This led to the Drinker-Shaw
iron lung in 1928, which was the first widely used
negative-pressure ventilator.
4/27/2017 4
5. • In 1931, Emerson modified these large devices, and the
Emerson tank ventilator became the standard for ventilatory
support
• 1950s – replaced by positive pressure ventilation.
• 1980s - s, increasing experience with positive-pressure
ventilation delivered through a mask in patients with obstructive
sleep apnea led to this type of ventilatory support, initially in
patients with neuromuscular respiratory failure.
• Success led to its adoption in other conditions, and noninvasive
ventilation became especially promising in the treatment of
patients with decompensated chronic obstructive pulmonary
disease
• Over time expanded to other conditions as well.
4/27/2017 5
8. • Non-invasive ventilation (NIV) is a relatively new
ventilatory mode that has been increasingly used in the
acute setting over the past 15 years, demonstrating
beneficial effects in the adult and pediatric population with
different types of respiratory failure. NIV recruits the
lung, increasing functional residual capacity, improves
respiratory dynamics, reduces respiratory work, and
optimizes gas exchange
4/27/2017 8
9. • Basic physiology differences also mean that the
complications derived from invasive mechanical
ventilation are more frequent and more severe in children
than adults.
• The difference in compliance leaves the neonate and
infants at risk of barotrauma secondary to positive
pressure invasive ventilation, since the thoracic wall
cannot contain or control a pulmonary over-inflation
4/27/2017 9
10. • Children’s lungs are much more prone to barotrauma, volutrauma,
biotrauma and atelectrauma than those of adults. The child’s lungs
also require earlier ventilatory support to avoid the pulmonary
collapse that threatens as soon as the child goes into
hypoventilation.
• Children’s respiratory muscles are less resistant to muscular
fatigue because they have a larger proportion of Type IIA glycolytic
fast muscle fibers, which are quite prone to fatigue and a low
proportion of type I slow oxidative fibers, which are more resistant to
muscle fatigue
•
4/27/2017 10
11. • In light of all the above, it could be said that non-invasive
mechanical ventilation seems to have been especially
developed for children, or perhaps, that the child’s lung
has been especially designed for non-invasive
mechanical ventilation
4/27/2017 11
13. NIV BENEFITS IN PEDIATRIC
PATIENTS:
• 1. By improving respiratory mechanics and assisting in
work of breathing, allows the respiratory muscles to rest.
• 2. By decreasing work of breathing, decreases total
oxygen consumption.
• 3. Decreases hypercapnia and increases the Vt through
the IPAP.
• 4. Increases functional residual capacity (FRC) and end-
expiratory lung volume (EELV) through both EPAP and
CPAP.
• 5. Prevents atelectasis formation by increasing the
difference between FRC and closure volume.
• 6. Helps maintain upper airway permeability.
4/27/2017 13
14. • 7.Decreases the symptoms of respiratory insufficiency, by
normalizing respiratory frequency and decreasing
dyspnea.
• 8. Improve the patient’s comfort (subjective sensation of
respiratory insufficiency)
• 9. The patient can stay awake and sedation is not
necessary.
• 10. Avoids the complications associated with
endotracheal intubation and endotracheal tubes.
4/27/2017 14
17. KEYPOINTS FOR USE OF NIV IN PEDIATRIC PATIENTS
1. Ventilators:
• Minimum peak inspiratory flow of at least 100 liters/min
(better if > 150 liters/min).
• Pressure modes (support and control).
• Good synchronization with patient breathing: high
inspiratory and expiratory trigger sensitivity.
• FiO2 programmer
2. Interfaces:
• High adaptability: Appropriate pediatric sizes.
• Choose the correct interface according to the type of
respiratory pathology to be treated.
• 3. Good Staff Training:
4/27/2017 17
18. 4. NIV Patient selection:
• First step indication: Chronic hypercapnic insufficiency.
• Second step indication: Acute hypercapnic failure.
• Third step indication: Acute hypoxemic failure.
5. Choose the correct moment for using NIV:
• After correct indication the rule is “the sooner the better”.
6. Always humidify and heat the gas flow:
7. Choose the correct environment:
• Intensive care unit for: Hypoxemic respiratory failure and
severe hypercapnic respiratory failure.
• Medical ward: Chronic hypercapnic failure and acute mild-
moderate hypercapnic respiratory failure.
4/27/2017 18
21. ETIOLOGIES FOR NIV-TREATABLE CHRONIC
HYPERCAPNIC RESPIRATORY INSUFFICIENCIES:
1.Central Nervous System Diseases:
Arnold-Chiari malformation
2. Neuromuscular Diseases:
a. Spinal Amyotrophia
b. Myopathies (congenital, mitochondrial, metabolic,
inflammatory)
c. Muscular Dystrophy (Duchenne’s Disease, etc.)
d. Guillain-Barré syndrome.
3. Upper airway Alterations:
a. Pierre-Robin Syndrome
4/27/2017 21
22. 4. Pulmonary Diseases:
a. Bronchopulmonary Dysplasia
b. Cystic Fibrosis
c. Pulmonary fibrosing diseases
d. Bronchiectasis
5. Respiratory Sleep Alterations:
a. Obesity-Hypoventilation syndrome
4/27/2017 22
23. Absolute contraindications
• Cardiac arrest
• Respiratory arrest
Relative contraindications
• Discomforts from the mask that cannot be relieved with
adjustments
• Large volume secretions
• Recurrent vomiting
• Impaired mental status (except due to hypercapnia)
• Recent upper airway or upper GI surgery
• Facial trauma , burns
• Hemodynamic instability
4/27/2017 23
24. Modes
A.CPAP
B.HHHFNC
C.Conventional ventilators
D.NIV ventilators
• Bi-level pressure preset ventilators:
• Ventilators with a BIPAP (Bi-level positive airway
pressure) have revolutionized NIV. It is still the most
frequently used NIV modality in most patients and in most
situations
• Parameters set are IPAP, EPAP
4/27/2017 24
27. HHHFNC
Mechanisms of actions of HFNC are:
• Washout of nasopharyngeal dead space resulting in
increased fraction of oxygen and carbon dioxide in the
alveoli
• Reduction of inspiratory resistance and work of breathing
by providing adequate flow
• Improvement of airway conductance and pulmonary
compliance by reducing the effect of cold air;
• Reduction of the cost of gas conditions by providing air
with 100 % relative humidity
• Providing an end-distending pressure to the lungs
4/27/2017 27
30. SET UP (NEJM june 2015, BTS 2008)
1. Explain to the patient, if time permits take an ABG
2. Select the mode.
3. Patients with hypercapneic respiratory failure, BIPAP is
better than CPAP.
4. If BIPAP is used, set initial settings as IPAP 10. EPAP
5cm of H2O. Initial settings of IPAP 10cms H2O titrated
rapidly in 2-5 cms increments at a rate of approximately
each 10 minutes with a usual pressure target of 20cms
H2O or until a therapeutic response is achieved or
patient tolerability has been reached.
• .
4/27/2017 30
31. 5. Strap the mask to the patient. Optimally tight. 2 fingers should
pass between strap and head.
6. Should fit around nose and mouth, not extend beyond chin.
7.Non-invasive ventilation can be used with a naso-gastric tube in
place, in which case this should be a fine bore tube to minimise mask
leakage. It is not necessary to place a naso-gastric tube simply
because a patient is to receive NIV.
8. Initial Fio2 to adjust SPO2 > 90%.
9. Do ABG after 30 min and adjust the ventilator settings. If
hypercapnea is present increase TV by increasing difference
between IPAP& EPAP.
10. If persistent hypoxemia, increase FiO2 or EPAP(but
proportionately increase IPAP to maintain PS)
4/27/2017 31
32. NIV in NIV ventilator
• NIV –PC/PS
• Pressure control or Pressure support
• Avoid too much leakage
• Trigger sensitivity may be problem
4/27/2017 32
33. Interface
Oronasal Mask.
Most frequently used to
provide noninvasive
airway access. It has a
silicone cushion that
forms a seal around the
nose and mouth.
May abrade the nasal
bridge.
Risk of aspiration in
emesis
4/27/2017 33
34. • Total-face mask
encompasses the
entire face, including
the eyes
• It does not abrade the
nose, but some
patients may find it
claustrophobic
4/27/2017 34
35. • The nasal mask and
nasal pillows cause
less claustrophobia,
but the mouth must
remain closed to
prevent air leakage
• Advantage- can speak,
eat, less risk of
aspiration in vomiting
4/27/2017 35
37. Recommendations from Pediatric acute lung injury
consensus conference June 2015
1. Consider early in disease in children at risk for PARDS
to improve gas exchange, decrease work of breathing, and
potentially avoid complications of invasive ventilation
2. Children with immunodeficiency who are at greater risk
of complications from invasive mechanical ventilation, may
benefit more from earlier NPPV in order to avoid invasive
mechanical ventilation. Weak agreement (80% agreement)
4/27/2017 37
38. 3. NPPV is not recommended for children with severe
disease. Strong agreement
4. Recommend the use of an oronasal or full facial mask to
provide the most efficient patient-ventilator synchronization
for children with PARDS. Weak agreement (84%
agreement)
5. We recommend that children using NPPV should be
closely monitored for potential problems, such as skin
breakdown,gastric distention, barotrauma, and
conjunctivitis.Strong agreement
6. Heated humidification is strongly recommended for
NPPV in children. Strong agreement
4/27/2017 38
39. 7.We recommend that intubation should be considered in
patients receiving NPPV who do not show clinical improvement
or have signs and symptoms of worsening disease, including
increased respiratory rate, increased work of breathing,
worsening gas exchange, or an altered level of consciousness.
strong agreement
8. To allow the most efficient patient-ventilator synchronization
and tolerance, sedation should be used only with caution in
children receiving NPPV for PARDS. Weak agreement (88%
agreement)
4/27/2017 39
40. STATUS ASTHMATICUS
• Reversible, diffuse lower-airway obstruction, caused by airway
inflammation and edema, bronchial smooth-muscle spasm, and
mucus plugging.
•This causes airflow limitation and premature airway closure,
which results in increased work of breathing due to:
(1) Active expiration by continuous activation of inspiratory
muscles in an attempt to empty the lungs, and
(2) High airway resistance and hyperinflation, which
overstretches the lungs and chest wall making it more difficult to
stretch them further to inspire adequately. Hyperinflation is
dynamic, and it brings progressive time constant increase which
leads to gas trapping, increasing PEEP(auto PEEP)
4/27/2017 40
41. • EPAP may offset intrinsic PEEP and may relieve the
uploading of respiratory muscles while maintaining
patency of smaller airways and recruits collapsed alveoli.
This diminishes respiratory workload and improves
ventilation–perfusion mismatch.
• IPAP may help inspiratory muscles to counteract airflow
limitation and chest wall overstretching and may improve
tidal volumes.
4/27/2017 41
42. Bronchiolitis
•Increase in use of non-invasive ventilation for infants with
severe bronchiolitis is associated with decline in intubation
rates over a decade (PCCM 2015)
•Humidifed oxygen and Hydration are the cornerstone in
severe bronchiolitis
•Bubble CPAP/HHHFNC/NIV
4/27/2017 42
43. Niv in Cardiogenic pulmonary edema
• Provides PEEP
• Prevents alveolar collapse and provides optimal lung
recruitment helps the lung to get its functional residual
capacity
• Invasive ventilator has sometimes deleterious effects on
heart dynamics
4/27/2017 43
44. MONITORING
• Monitoring should include a mixture of physiological
measures and clinical assessment parameters (A)
- Monitoring should include continuous pulse oximetry and
ECG monitoring for the first 12 hours and RR, PR, BP and
assessments of consciousness regularly [B]
- Arterial blood gases should be taken as a minimum at 1, 4
and 12 hours after the initiation of NIV [A]
4/27/2017 44
45. • These should be used to assist in both formulating a
management plan and, within the first 4 hours of NIV, the
decision as to the appropriateness of escalating to
intubation [A]
• Compliance with NIV, patient-ventilator synchrony and
mask comfort are key factors in determining outcome and
should be checked regularly [C]
4/27/2017 45
46. ESCALATION
• A management plan in the event of NIV failure should be
made at the outset [C]
• A decision to proceed to invasive mechanical ventilation
should normally be taken within 4 hours of initiation of NIV
[A]
• Intubation where appropriate is the management of
choice in late (>48hrs) NIV failures [B]
4/27/2017 46
47. Treatment Duration
• Patients who benefit from NIV during the first hours of
treatment should receive NIV for as long as possible during the
first 24 hours [A]
• Treatment should last until the acute cause has resolved,
commonly 2-3 days [C]
• In patients in whom NIV is successful
(pH ≥7.35 achieved, resolution of underlying cause and
symptoms, respiratory rate normalized) it is appropriate to start a
weaning plan [C]
4/27/2017 47
48. Weaning
• Treatment reduction should affect day time ventilation
periods first [C].
• After withdrawal of ventilatory support in the day a further
night of NIV is recommended [C]
• The weaning strategy should be documented in the
nursing and medical records [C]
4/27/2017 48
51. TAKE HOME MESSAGE
• What is NIV and why it is used
• To be familiar with CPAP, HHHFNC, NIV
• Indications and contraindications of NIV
• Modes of providing NIV in our setup
4/27/2017 51
