This document discusses indications for and goals of assisted ventilation as well as ventilator settings and modes. The key points are: 1. Assisted ventilation is indicated for respiratory failure, cardiovascular failure, neuromuscular failure, and airway protection. The goals are to provide optimal gas exchange while reducing work of breathing and risk of injury. 2. Initial ventilator settings depend on the underlying condition but generally involve a balance of pressures, rates, and oxygen levels to target appropriate oxygenation and carbon dioxide removal. 3. Common modes include assist-control, synchronized intermittent mandatory ventilation, and pressure support. Weaning involves gradually reducing support while monitoring blood gases and clinical stability.

1. Assisted Ventilation

2. Indications
Respiratory Failure
Type I Hypoxemic airway – lung
Type II Hypercarbia CNS - Muscles
PaO2 <60mmHg at FiO2 60% or PaCO2>60mmHg
Cardiovascular Failure
Shock states ( central / peripheral )
Neuromuscular Failure
Airway protection

3. CPAP Failure
Pao2<50 while breathing 60-80% o2
Resp Acidosis with PH <7.20 -7.25 or Paco2 >60-
65
Persistent hypoxemia and Met Acidosis with BE >-
8
Marked retractions on cpap
Intractable apnea and bradycardia

4. LUNG MECHANICS

5. Ventilation - Diffusion - Perfusion
Ventilation How gas gets into the alveoli and then out
Diffusion How gas gets across the alveolar walls
Perfusion How blood flows along the alveoli

6. Compliance
Compliance is a measurement related to the elasticity of the
lung.
∆Volume
C = -----------------
∆Pressure
A low compliance inicates a stiff lung so It needs high
pressure and long IT to inflate
 Normal compliance = 3-6 mL/cmH2O.
 Compliance is decreased with surfactant
deficiency (0.5-1 mL/cmH2O),

7. Resistance

8. .
.
The range of values for total airway plus tissue respiratory
resistance for healthy newborns is 20-40 cm H2 O/L/s; in
intubated newborns, this range is 50-150 cm H2 O/L/s.
resistance > 100 mean obstructive disease

9. Ex : RDS
Stiff lung Compliance Decreased Resistance
Normal
Therefore
Improving oxygenation by prolonging inspiratory time
usually causes no harm

10. Ex : MAS
Compliance Normal Resistance Increased
These patients are very liable to air trapping and PAL syndrome it is
important to provide a long expiratory time during ventilation

11. Minute Ventilation
Ti
Te
Vt f
MV
MV = VT * f

12. Goal of Assisted Ventilation
Provide optimal pulmonary gas exchange .
Oxygenation Get oxygen into blood
Ventilation Remove CO2 from blood
while Reducing patient‘s Work of Breathing
Optimizing patient‘s Comfort
Minimizing risk of lung injury /circulatory impact

13. Oxygen therapy
Methods of delivery
Free flow oxygen
Headbox
Nasal canula
CPAP
Mechanical ventilation
Hazards of O2 therapy
Little O2 CNS morbidity
Excess O2 ROP - BPD

14. Modes Of Ventilation

15. AC PCV IMV(VC , PC)
 An inspiratory cycle is initiated either by the
patient's inspiratory effort or, if no patient effort is
detected within a specified time window, by a
timer signal within the ventilator
 Every breath delivered consists of the operator-
specified tidal volume (Full support). Ventilatory
rate is determined either by the patient or by the
operator-specified backup rate, whichever is of
higher frequency

16. AC
Assist-Control Ventilation

18. SIMV (VC ,PC)+PS
 The major difference between SIMV and AC is
that in the former the patient is allowed to
breathe spontaneously, i.e., without ventilator
assist, between delivered ventilator breaths (PC
+PS)
 SIMV allows patients with an intact respiratory
drive to exercise inspiratory muscles between
assisted breaths. This characteristic makes
SIMV a useful mode of ventilation for both
supporting and weaning intubated patients

19. SIMV
Synchronized Intermittent Mandatory Ventilation

20. pressure-support is usually set at 30 to 50 % of the
difference between the PIP and PEEP

21. Pressure support ventilation (SPONT) CPAP
PSV
Fixed amount of pressure augments each
patient’s breath and is delivered by ventilator
while patient determines all other settings
Rate - Ti - Flow

23. Ventilator
MECHANICS

24. Peak Inspiratory Pressure
(PIP) “PC”
Pip 18-25 cmh2o to obtain VT 4-6?ml/kg
Changes determine the pressure gradient
between onset and end of inspiration
Increase PIP leads to:
1 - Increase tidal volume
2 - Increase CO2 elimination lead to
decrease PaCo2
3- Increase Paw improve oxygenation.

25. Peak Inspiratory Pressure
(PIP)
Risks (4+)
1- Increase barotrauma, air leak and
BPD
2- Impairs cardiac function

26. Positive End Expiratory
Pressure (PEEP)
A minimum of 2 -5 cm H2O
Significance:
1. Prevents alveolar collapse at end of
expiration
2. Improves V/Q

27. Positive End Expiratory
Pressure (PEEP)
Risk of excessive increase (2+)
1. Decrease tidal volume and CO2
elimination …… increase PaCO2
2. Impaired venous return and cardiac
output

28. Frequency (Rate)
Synchrony is provoked when ventilator
rate is similar to infant’s own breathing
rate
Starting RR : newborn 40-60/min.
infant &child 20-40/min
adults 8-15/min
High rate : may lead to small increase in
Pa O2

29. Frequency (Rate)
Precaution : Higher frequency leads to
a.shorter TE , reduction of pressure
gradient
and decrease PaCO2

30. I / E Ratio
 Normal ratio is
 1:1.2 or 1:1.5 (newborn)
 1:2 (children)
Ti (inspiratory time) =
0.3-0.5 sec(newborn),0.5-1sec (child)
 Higher ratio leads to increase Paw and
improves oxygenation
 Risk of prolonged inspiration (3+)
1 . Impedes venous return

31. FiO2
Changes alter alveolar O2 tension and
thus oxygenation
Start with 60% then decrease downward

32. Suggested initial settings for someSuggested initial settings for some
diseases:diseases:
Preterm 1.2 kg
RDS
(Restrictive)
3 kg Infant
pneumonia
(Restrictive)
3 kg Infant
MAS
(Obstructive)
Full term
HIE apnea
(normal
lung)
PiP High 18-25 High 18-30 High 25-30 Low 12-20
Peep
High
4-6
High
5
Low
3
Low
below 3
Ti
Long
0.3-0.5
1:1.2
Long
0.3-0.5
1:1.2
Short
0.3
1:3
Short
0.3
1:2-3
Rate
Medium
40-60
Medium
40-60
Rapid
40-60
Slow
30-40
FiO2
Guided by
oximeter
High
start 40-60%
High
start 40-60 %
High
start 40-60 %
Low
below
40%

33. Pressure - Time - Flow Waves
PIP
PEEP
Ti Te
MAP
Rate
TV
MV

34. MAP
 MAP(PAW) = K ( Pip – Peep ) ( Ti/Ti+Te )
+ Peep
N 10-12 cmh2o
MAP > 14 >>air leaks
 PEEP
 PiP (risk of barotrauma )
 Ti (consider I:E ratio for auto PEEP)
 Flow (Increase airway resistance & risk of barotrauma )

35. Subsequent Settings
1 . To increase PaO2
1- Increase FiO 2(risk 0 +)
2 - Increase PEEP ( risk 2 +)
3 - Increase Ti ( risk 3 + )
4 - Increase PIP ( risk 4 + )

36. Subsequent Settings
2 . To decrease PaCO2
1 - Increase rate ( risk 0 )
2 - Increase PIP ( RISK 4 + )

37. Ventilatory management of RD
Aims :
 PaO2 50 - 80 mmHg
 PaCO2 45 - 65 mmHg
 pH 7.25 - 7.45
Precaution
 Start xanthine before extubation
Dexamethsone???

38.  The goal of therapy for patients with
RDS(HMD)
a pH of 7.25-7.4, PaO2 of 50-70 mm Hg,
and PCO2 of 40-65 mm Hg,
oxygen saturations in the 88% to 95%
range,
In the smallest infants (<1,250 g birth
weight), lower oxygen saturation targets
(85%-92%) may be preferable

39.  The goal of therapy for patients with BPD
pH at 7.20-7.40, partial pressure of carbon
dioxide at 45-65 mm Hg, and partial
pressure of oxygen at 50-70 mm Hg , The
optimal range of oxygen saturation in BPD
is controversial, but maintain saturation of
arterial oxygen (SaO2) at 90-95%

40.  The goal of therapy for patients with Persistent
pulmonary hypertension of the newborn
PaO2 at 80-100 mm Hg to minimize hypoxia-
mediated pulmonary vasoconstriction; adjust
ventilatory rates and pressures to maintain an
arterial pH of 7.45-7.55 (sometimes combined
with bicarbonate infusion). Take care to prevent
extremely low PaCO2 (<30 mm Hg), which can
cause cerebral vasoconstriction and subsequent
neurologic injury

41. Drugs ? M V
Anesthesia ( Local ) Lidocaine 0.5% 5mg/kg SC=1ml/kg
EMLA 5% cream for 1 hr
Analgesia Morphine 0.02 mg /kg/hr
Fentanyl 0.2 mic/kg/hr
Sedation Midazolam 0.1mg /kg/dose
phenobarbitone
fentanyl
Muscle relaxation Pancuromium O.1mg /kg/dose
babies who fight the ventilator despite sedation
who require very high setting PIP>30
Antinflamatory Dexamthsone 0.25mg /kg
12 h before extubation 3 doses

42. Criteria for weaning
 If the infant is clinically and metabolically stable as evidenced by
reduction of the work of breathing, increased chest expansion and
aeration by chest auscultation and radiographic evidence of
improved lung volume.
 If the infant has an efficient spontaneous respiratory drive.
 If the infant is able to maintain satisfactory blood gas exchange:
► PaO2 >50 mmHg
► Optimal PaCO2 .a PaCO2 of 50-60 mmHg may be tolerated
(permissible hypercarbia), provided that pH is >7.25
 When an infant has been weaned to a mean airway pressure of 6
cm H2O and a low (40%) FIO2, extubation should be considered.
A RSBI value of </= 8 breaths/ml/kg had a sensitivity of 74% and
specificity of 74%, whereas a CROP value of >/= 0.15
ml/kg/breaths/min had a sensitivity of 83% and specificity of 53% for
extubation success.

43. Weaning(newborn)Weaning(newborn)
1-Decrease FiO2 by 5% increments down to
30%
2-Decrease Pip by 2cm down to 12-18cm H2O.
3-Decrease Peep by 1-2cm down to 2-4cm H2O.
N.B:N.B: Coordinate between PiP & Peep
4-Decrease Rate by increments of 5/min down
to 20
5-Discontinue to nasal canula or Ncpap with
higher FiO2.

44. Sudden deterioration of baby on
MV
 Think DOPE (VTE=VTI 20%)
Dislocation
Obstruction
Pneumothorax
Equipment failure

45. BiLevels

46. What is BiLevel Ventilation?
 Is a spontaneous breathing mode
in which two levels of pressure
and hi/low are set
 Enabled utilizing an active
exhalation valve
 Substantial improvements for
spontaneous breathing
better synchronization, more options
for supporting spontaneous
breathing, and potential for improved
monitoring

47. BiLevel Ventilation
Synchronized TransitionsSpontaneous Breaths
Spontaneous Breaths
PPawaw
cmHcmH2200
6060
-20-20
1 2 3 4 5 6 7

48. PRVC

50. THANK YOU