International conference «Actual approaches to the extremely preterm babies» (Kyiv, Ukraine, March 5-6, 2013)

1. Nonivasive Respiratory Support - NIV
High Frequency Ventilation - HFV
Iwona Maroszyńska
Department of Neonatal Intensive Care and Congenital Malformations
Memorial Institute of Polish Mother‟s Health Center
Київ 2013

2. Lung protective strategy
Nonivasive Respiratory Support
High Frequency Ventilation HFV

3. • High chest compliance • Newborn‟s chest
– Bone underdevelopment – More cylindrical
– Intercostal muscles – Shorter intercostal muscles
– Sleep REM – Diaphragm horizontal position
• Muscles tone
• Ineffective respiratory effort
• Low lung compliance
– Surfactant insufficiency
– Fewer terminal airspaces
– More stroma
VT ↓; f↑; grunting

4. • Elastic recoil (compliance/elastance)
– The tendency of stretched object to return to their original shape
• Inspiratory muscles relaxation during exhalation
• Chest wall
• Diaphragm recoil
• Lungs
– Surfactant, bone development
• Viscous resistance
– Fewer terminal airspaces
– More stroma

5. lung-chest wall system = pressure-volume characteristic (lung + chest wall)
FRC - outward recoil force of the chest wall = inward elastic forces of the lung
(resting state of the respiratory system)

6. • Closing volume
– < FRC
– = RV
• Neonate
– Closing volume ↑ FRC
Crit Care Med 2005 Vol. 33, No. 3 (Suppl.)

7. Pulmonary vascular resistance

8. Pulmonary vascular resistance
Pa Palv Pv
*** * **
Pa Palv Pv
*** ** *
Pa Palv Pv
III ** *** *
I
II
Modified from West JB: Respiratory Physiology:
The Essentials, 2nd ed. Baltimore, Williams & Wilkins, 1979, p. 39
.

9. Pulmonary vascular resistance
LV preload ↓
shunt I Pa Palv Pv
** *** *
PTV
FRC
Hakim TS, Michel RP, Chang HK (1982) Effect of lung inflation on pulmonary vascular
resistance by arterial and venous occlusion. J Appl Physiol 53(5):1110–1115

10. - Good conditions for the contact of blood and endothelial cells
- High blood flow
- Well developed microcirculation
- Low perfusion pressure
- Highly represented macrophage system
- Direct contact with the external environment - colonization

11. Disadvantages of Ventilation via ETT
• Cardiovascular and cerebrovascular instability during ventilation
• Complication of ETT
– Subglotic stenosis
– Tracheal lesions
• Acute and chronic lung damage
– Volutrauma
– Barotrauma
– Shear
• Infection
• If you do not ventilate en infant, it‟s hard to cause BPD

12. Compensatory mechanisms
• f↑ VT ↓
• Grunting
• Mechanical Ventilation
– Open lung strategy
• CPAP
– Lung protective strategy
• Low VT
• PEEP
• PIP < 25 – 30
• Synchronized

14. Noninvasive ventilation
High frequency ventilation
• Open Lung Strategy
– Alveolar collapse
– Alveolar overdistention
• Benefits from open lung strategy
– Decreased intrapulmonary shunt
– Improved oxygenation
– Reduced PVR
• Optimal recruitment
– Reduced intrapulmonary shunt < 10%
– Adequate oxygenation without supplemental oxygen
• Practical optimal recruitment
– FiO2 ≤ 0,3

15. Lung Recruitment Maneuver
24
B
20 FiO2 0,3 C
16
12 D
A FiO2 0,3
8 FiO2 0,6
A
4 FiO2 0,8
0

16. Target fraction of FiO2
• Retrospective study
– To retrospectively evaluate if HVS is associated with better oucome
– FiO2 ≤ 0,25
– FiO2 > 0,25
• No - 28 vs 23
• GA < 26,1 vs 25,9 hbd
• Birth weight 603 vs 703
J Matern Fetal Neonatal Med. 2011 in press
Tana M et all
Unexpected effect of recruitment procedure on lung volume measured by respiratory inductive plethysmography (RIP)
during high frequency oscillatory ventilation (HFOV) in preterm neonates with respiratory distress syndrome
(RDS).

17. Target fraction of FiO2
• Results
– MAP – 12,8 vs 11,2
– FiO2 - 0,25 vs > 0,25
– Extubation – 3,5d vs 9 d (p=0,005)
– Oxygen - 488 d vs 1109 d (p=0,02)
– Mechanical ventilation 187 vs 525 (p=0,03)
– Surfactant > 1 dose 1 vs 6 (p=0,04)
– BPD - NS
J Matern Fetal Neonatal Med. 2011
Tana M et all
Unexpected effect of recruitment procedure on lung volume measured by respiratory inductive
plethysmography (RIP) during high frequency oscillatory ventilation (HFOV) in preterm neonates with
respiratory distress syndrome (RDS).

18. What is the HFV ?
• HFV
– Complex process of mixing gases
– Normal human lung > 170/min
• Small tidal volume
– VT < anatomic dead space 1-3ml/kg
• Very rapid ventilator rates
– > 4 x physiological respiratory rate
– 2 - 20 Hz = 120 – 1200 breaths/min.
• MAP
– HFV > CMV

19. Back to the physiology…
• Alveolar ventilation
– VA = VT – VD
• HFV
– VT ≤ VD → VT – VD ≤ 0
– VA ≤ 0

20. HFV vs CMV
• VT
– Const. f ≤ 25 -30/min. > 30/min. VT ↓
• Valv = (VT – VD) x f
– F > 75/min. ↓ → VA = VT2f
– f > 75/min. - VT determined by Ti
Using conventional infant ventilators at unconventional rates
Pediatrics. 1984 Oct;74(4):487-92.
• Flow
Boros SJ, Bing DR, Mammel MC, Hagen E, Gordon M
• VT
• Amplitude ↑
• PIP – PEEP
• f↑ → VT↓
• MAP
• PIP ; PEEP

22. Why HFV?
• VT < VD 1-3ml/kg
• Possibility of independent management of the oxygenation and
ventilation
• Preservation of normal lung architecture even when using high MAP
• Optimal lung inflation
– The lung volume at which the recruitable lung is open but not
overinflated

24. PIP – 25 cmH2O
PEEP – 5 cmH2O
I : E – 1 : 2 > 75/min 1 :1
F = 10 L/min
Boros SJ, Bing DR, Mammel MC, et al: Pediatrics 74:487, 1984
PIP – 25 cmH2O
PEEP – 5 cmH2O
I:E–1:2
Mammel MC, Bing DR: Clin Chest Med 17:603, 1996

25. Consepts of gas transport….
• Convection ventilation or bulk flow
• Taylor dispersion and molecular diffusion
– A high velocity of gas travels down the center of a tube, leaving
the molecules on the periphery unmoved
– High flow facilitates diffusion
• Pendelluft effect
– Regional differences in time constants for inflation and deflation
cause gas to recirculate among lung
– Open lung allows to gas recirculate between alveoli
• Cardiogenic mixing

27. Crit Care Med 2005 Vol. 33, No. 3 (Suppl.)

28. Is the HFV more effective than CMV?

29. Study Year Study disign Results
60 – 150 breaths/min
Observational: Sjostrand V 2000 adults and children HFPPV adequate
1977
Acta Anesthesiol Scand and 32 neonates with respiratory support
RDS
24 neonates with RDS
Observational: Bland RD
1980 60 – 110 breaths/min, Improved outcome
Crit Care Med
volume preset vent.
673/346 preterms BPD ND, IVH↑, PVL↑,
HiFi study 1989
750-2000g Air leak↑
M-RCT (OCTAVE) 346 neonates
Oxford Region Controlled Trial of Artificial
1991 HFPPV vs CMV HFPPV ↓ air leak
Ventilation study group
Arch Dis Child
60 vs 20 - 40
CMV trend ↓ BPD w
Pardou A 22 neonates, HFFI 28 dobie i 36 tyg.
1993
Int Care Med rescue therapy 63% vs 80%; 25% vs
40%
284 neonates
Thome U (RCT) 1999 24-29hbd < 1000g Infant Star ↑ air leak
HFV Inf Star

30. BPD
28 days; 36 weeks PMA
Study group/
Trial 28 – 30 d 36 PMA HLVS Surfaktant
HFV
RCT CO 83 ≤ 1750
Clark RH HFOF SM/CV – 27
1992 HFOV SM – 30 P=0,008 P=0,013
RMCT (Provo)
125 < 35 weeks
Gerstmann 100%
(1500;30,9) P < 0,05 P < 0,05 36 PMA
DR redosing
HFOF SM – 64
1996
RMCT 499
100% (4)
Courtney < 1200g P = 0,046 all
redosing
2002 HFOV SM - 244

32. • N=273
• GA – 24 -29
• Birth weight < 1000g
• Randomization
– 142 min - 145 min
• HFOV
– Reduction of surfactant doses - 30% vs 64%
– Higher incidence IVH 24% vs 14%
Moriette G et al. Pediatrics 2001,107:363-72.
Prospective randomized multicenter comparison of high-frequency oscillatory ventilation and conventional
ventilation in preterm infants of less than 30 weeks with respiratory distress syndrome

33. Meata-
Trials 28 – 30 d 36 PMA HLVS Surfaktant
analysis
Cools F RR – 0,5 RR – 0,44
16 trials ND
1999 CI: 0,32, 0,78 CI: 0,16, 0,73
Hendreson-
or death 28-30 days
Smart DJ Trend toward
6 trials trend toward RR – 0,5 Similar to
2000 decreasing
Rand. – 12h decreasing CI: 0,36, 0,76 HLVS
Cochrane: in HFV
in HFV Death or BPD
CD000104
Hendreson-
Smart DJ NNT 17
Results the Results
2003 10 trials Or death
same the same
Cochrane: NNT - 20
CD000104
Hendreson-
Smart DJ 15 trials
ND borderline 36 PMA
2007 3585 ND
significance
Cochrane: neonates
CD000104

34. 3652 neonates
Mortality at 28 -30 days
BPD – 36 PMA

35. • HVLS in HFV - ND
• HFOV
• Not used LPS in CV
• Randomization 2 – 6 hours
• I:E–1:2
• Air leaks – more frequently in HFOV

37. • Secondary end points
– Gross pulmonary air leaks
• pneumothorax, pneumomediastinum, pneumopericardium
– Any pulmonary air leaks ↑*
• Gross pulmonary air leaks + PIE
– PDA – surgical ligation ↓
– ROP > 2 ↓*
– Final extubation HFOV < CV

38. • Ventilator type ND
– Sensormedics vs others vs „flow interrupter”
– HVLS
• Trials with HLVS
– Lower target of FiO2
• Time of randomization
– Death or BPD or neurological event
•1 – 4 h vs after 4h: HFOV (p=0,01)

39. No of trials – 15
• Outcome measures
– Death
– BPD at 36 weeks PMA
• Other variables
– Type of ventilator
• 11 – HFOV
– 7 – Sensormedics
• 2 – HFJV
• 2 - HFFI
– Ventilation strategies applied in the HFV and CV treatment groups
– Time on mechanical ventilation before randomization

40. HVLS i LPS

41. Neurological outcome
IVH, PVL
Study group/ IVH
Trial PVL
HFV Grades: 3,4
RMCT
HiFi No – 673/327 26 vs 18 12 vs 7
1989 750g – 2000g P = 0,02 P = 0,05
ND (HiFi)
RR 1.31, Fixed:
Cools F 95% CI: 1.04, 1.66
16 trials Random: RR 1.34, ND
1999
(95%
CI: 1.05, 1.70

42. Longterm neurological outcome
Study group/ No Pulmonary Neurodevelopmental
Trial
HFV followed up function outocome
386 (77%) 16 – 24 m.
RMCT 673/327
ND Bayley score > 83
HiFi 750 – 2000g 432 (82%)
(No 223-43%) no major defect
1989 Surv. - 524
CV ↓ (54% vs 65%)
1 year
RMCT
92/46 BPD in chest x Developmenta delay –
Ogawa 91 (100%)
750 - 2000 –ray 9% in both groups
1993
2% vs 4% ND
RMCT
125 < 35
(Provo)
Available 79
Gerstmann 69 (87%) ND ND
(1500;30,9)
DR
HFOF SM – 64
1996
MRCT 428 – 73%
797/400 22-28 month
UKOS 373 – In 9% sever
Surv. 592 40%
Marlow N „window” 38% other disabilities
23 – 28 PMA ND
2006 (211vs217)

43. HFOV – indications
• Air leak syndromes
– Pulmonary interstitial emphysema ( PIE)
– bronchopleural or tracheoesophageal fistula
• Until at least 24 hours after the air leak resolved

44. HFOV - indications
• Severe uniform lung disease
– Respiratory distress syndrome
– Pneumonia
– ARDS

45. HFOV - indications
• Severe nonuniform disease such
– MAS - meconium aspiration syndrome
– Others aspiration syndromes
• Complication – air - trapping

46. HFOV - indications
• Parenchymal lung disease and require inhaled nitric
oxide therapy
Kinsela JP wsp – Randomised, multicenter trial of iNO and HFOV in severe PPHN. J Pediatr 1997;131: 55-62
• Pulmonary hypoplasia
– CDH
– Oligohydramnios sequence
• Severe chest wall restriction or upward pressure on the
diaphragm
– Gastroschisis
– Omphalocoele
– NEC

47. HFOV - indications
• Severe respiratory failure meeting the criteria for ECMO

48. HFOV strategy
Optimal
lung volume strategy
MAP
MAP 2-3 cmH2O in 1-2 cmH2O steps
Frequency - 10 Hz
above the CMV until
oxygenation improves
Aim: to maximise recruitment of alveoli

49. HFOV strategy
Low
volume strategy
Adjust amplitude
MAP equal to the to get an adequate Frequency - 10 Hz
CMV
chest wall vibration.
Aim: to minimise lung trauma

50. HFOV strategy
• Obtain an early blood gas and adjust settings as appropriate
• Obtain chest radiograph to assess inflation
– Initial at 1-2 hrs
• baseline lung volume on HFOV (aim for 8 ribs).
– A follow-up in 4-6 hours
• to assess the expansion
– Repeat chest radiography with acute changes in patient condition
• Reduce MAP
– chest radiograph shows evidence of over-inflation (> 9 ribs)

51. Poor Over Under Over
Oxygenation Oxygenation Ventilation Ventilation
Increase FiO2 Decrease FiO2 Increase Amplitude Decrease Amplitude
Decrease Frequency Increase Frequency
Decrease MAP
Increase MAP (1-2Hz) (1-2Hz)
(1-2cmH2O)
if Amplitude Maximal if Amplitude Minimal

52. Weaning
• Reduce FiO2 to < 40% before weaning MAP (except overinflation)
• Reduce MAP in 1-2cm H2O increments to 8-10 cm H2O
• Air leak syndromes (low volume strategy)
– Reducing MAP takes priority over weaning the FiO2
• Wean the amplitude
• Do not wean the frequency
• Discontinue weaning when MAP 8-10 cm H2O and Amplitude 20-25
• Infant is stable, oxygenating well and blood gases are satisfactory
– extubation to CPAP or switched to conventional ventilation

53. Suctioning
• Indications
– diminished chest wall movement (chest wobble)
– elevated CO2 and/or worsening oxygenation
– visible/audible secretions in the airway
• Avoid in the first 24 hours of HFOV, unless clinically
indicated.
• In-line suctioning must be used
• Press the STOP button briefly while quickly inserting and
withdrawing suction catheter (PEEP is maintained)

54. 2006 OPEN FORUM Abstracts
OPEN VERSUS CLOSED SUCTION DELIVERY DURING HIGH FREQUENCY
OSCILLATORY VENTILATION (HFOV)
Dennis Gaudet, RRT; Matthew P. Branconnier, RRT, EMT; Dean R. Hess, PhD,
RRT, FAARC. Massachusetts General Hospital and Harvard Medical School,
Boston MA.

55. Summary.…
• HFV is an effective treatment modality in a variety of clinical
situations
• The most important contribution of HFOV is that it helped clinicians
overcome the fear of using adequate distending airway pressure
• The most important is to achieve optimal lung volume, I:E – 1:2
• When used in appropriately selected patients with the optimal
volume recruitment strategy and careful attention to avoide
hypocapnia, HFOV is capable of reducing the incidence of CLD
• Recent meta-analyses have suggested that surfactant, antenatal
steroids, and improvements in conventional mechanical ventilation
with the use of lung-protective strategies have eliminated any
advantages of HFV as a primary mode of ventilation

56. Nasal Ventilation: How does it work?
• Increase in FRC
– Alveolar recruitment due to higher MAP
– Decrease in intrapulmonary shunt
– Protection of surfactant
– Increases alveolar surface area for gas exchange
• Improves oxygenation
• Increase in VT and minute volume

57. NIV - History
• August Ritter von Reus 1914
– Bubble CPAP
• 1940s
– High altitude flying
• 1967
– PEEP was added to MV
• 1960s
– Neonates PEEP=0

58. NIV - History
• Harrison (1968)
– Grunting was producing positive end expiratory pressure (PEEP)
• Gregory (1971)
– Clinical use of CPAP in premature neonates with hyaline membrane
disease (RDS)
• Avery (1987)
– The lowest incidence of BPD, at Columbia where they used much more
CPAP
• Nasal Continuous positive airway pressure (NCPAP)
– By far the most commonly used form of NIV in neonates today

59. When is NIV used ?
After birth
After extubation
To treat apnea

60. Nasal CPAP Delivering Devices
• Components
– Circuit for continuous or variable flow of inspired gases
• Continuous flow – gas flow generated and directed against the
resistance of the expiratory limb
– Nasal interface
• single or bi-nasal prongs (Argyle & Hudson), mask, NP tube
– Device to generate positive airway pressure

61. Know Your CPAP
• Continuous flow: flow constant irrespective of phase of
respiration
– Ventilator generated CPAP (conventional CPAP)
– Bubble: CPAP varied by immersion of expiratory tubing
• Flow varies with immersion depth and affects CPAP
• Variable flow: CPAP varied by varying the flow rate
– Infant flow, Arabella, Aladdin
– Bi-level (“SiPAP”)
Courtnay SE et al; Pediatr Pulmonol; 36; 2003
Lipsten F et al; J Perinatol; 2005
Boumecid H et al; Arch Dis Chid Fetal Neonatal; 2007

62. Conventional Ventilator CPAP vs. Infant Flow CPAP
for Extubation (n=162)
Extubation Failure Rate:
Conv. CPAP= 38.1%
IF-CPAP= 38.5%
Infant Flow CPAP is as effective as conventional CPAP
Stefanescu BM et al. (Winston-Salem, NC) Pediatrics 2003

63. Infant Flow Driver CPAP
Pressure is generated by Varying the Flow Rate
• Reduced work of breathing
• Maintains uniform pressure
Fluidic Flip or Coanda Effect

65. CPAP Interfaces
Argyle Prongs Hudson Prongs Nasopharyngeal
Catheter
Nasal mask
Nasal Cannula
Inca Prongs
R ~ F L / r4

66. Bi-Nasal vs Single Prong CPAP in ELBWI
Bi-Nasal Prongs Single Prong
p
(n=41) (n=46)
BW, g mean (SD) 790 (140) 816 (125) NS
GA 26 (1.9) 26 (1.9) NS
Age at extubation, days,
3 (1-9) 3 (1-6) NS
Median, IQ range
Extubation Failures 24 % 57 % 0.005
In < 800 g 24 % 88 % <0.001
Reintubation in < 800 g 18 % 63 % 0.023
Bi-Nasal Prongs are more effective than Single Prong
Davis P et al. (Melbourne) Arch Dis Child 2001

67. Single-prong vs double-prong NCPAP ventilation: effect on
extubation failure
De Paoli A: Cochrane Database Rev; 2008; CD002977

68. NCPAP at birth
• Intubation in the delivery room was reduced from 84% to 40%
» Linder W et al.; Pediatrics; 1999;
• Intubation in the delivery room was reduced from 89% to 33%
» Aly H et al.; Pediatrics; 2004;
• Lack of RCT
– „…the dramatic effect of CPAP (was) observed after a brief period of treatment in
all patients.”
» Novogroder et al.; J Pediatrics: 1973
• „…Although one or two such (RCT) studies of CPAP would be
welcome, many more „would be foolish.”

69. Davis PG: 2003;
Cochrane Database Rev
CD000143

70. NCPAP - 8 Studies; 2001-2009
Extubation failures - 20-80%
90
Bi-Nasal vs. 80
80 Single Prongs
70
NCPAP vs.
60 57 Surf +
IFD vs.
V-CPAP 46 NCPAP*
50 IFD vs.
38,5 38,1 B-CPAP 39
40 33 33
29
30 24 26
19,7
20
10
0
Davis-01 Stefanescu- Finer-04 Booth-06 Morley-08 Gupta-09 Sandri-09 Rojas-09
03
Ramanathan R. J Perinatol 2010; 30: S67-72

71. What to do when NCPAP fails?
when should the neonate be intubated ?
• NCPAP – Faillure rate -20 -80%
• Definition of CPAP faillure
– FiO2 > 0,6 → 0,75
– FiO2 > 0,35 – 0,4
– COIN trial
• FiO2 > 0,6; pH < 7,25; PaCO2 > 60mm
• Apneic episodes > 6/6hour requiring stimulation or >1 requiring PPV

72. NIPPV
• Added positive pressure inflation to a background of
NCPAP
• How NIPPV improve clinical outcomes
– PIP results in only a slight increase in VT when delivered during
spontaneous breathing
– Occasionally lead to chest inflation when delivered during apneic
period
» Owen LS et al.; Arcg Dis Child Fetal Neonatal Ed; 2011

73. sNIPPV in Preterm Infants with RDS
sNIPPV -242; nCPAP - 227;
NCPAP sNIPPV
P
(n=227) (n=242)
Birth Weight, g 964  183 863  198 < 0.001
Gestational Age, wks 27.9  2.4 26.4  1.7 < 0.001
Antenatal Steroids, % 92 94 0.274
Surfactant Rx, % 68 85 < 0.001
BPD, Total population 25 % 35 % 0.028
BPD in 500-750 g 67 % 43 % 0.031
BPD in 751-1000 g 23 % 35 % 0.097
BPD in 1001-1250 g 14 % 21 % 0.277
sNIPPV when compared to NCPAP was associated with decreased
BPD, BPD/Death, NDI, and NDI/Death
Bhandari V et al. Pediatrics 2009

74. NCPAP vs. NIPPV: 9 RCT; 1999 - 2011
Extubation Failures
60
Extubation Failures 5-25%
49
50
44
42 41
40 39
40 37
34
30 25 25
18,9
20 17
15 15
10
10 5 6 6
0
Friedlich-99 Barrinton-01 Khalaf-01 Kugelman-07 Moretti-08 Ramanathan- Kishore 09 Lista-10 Meneses-11
(Ramanathan) 09
* P <0.05 Modified from Ramanathan R. J Perinatol 2010

75. NCPAP vs. NIPPV: 8 RCT; 1999 – 2011
BPD
60 56
53
50 44
39
40 35 33
30 2526,5
22 21
20 17
10
10 6 7,7
2 2,7
0
Barrinton-01 Khalaf-01 Kugelman-07 Bhandari-07 Moretti-08 Ramanathan-09 Kishore-09 Meneses-11

76. •NIPPV
• Lower risk of respiratory faillure
• Apnea
• Respiratory acidosis
• Increased oxygen requirements
To prevent reintubation
Davis PG; Cachrane Database Rev. 2001; CD003212

77. S-NIPPV and NS-NIPPV
• NCPAP vs S-NIPPV vs NS-NIPPV (20-40/min)
– VT, minute ventilation, gas exchange – ND
– S-NIPPV
• Less inspiratory effort
• Better infant – ventilator interaction
– NS-NIPPV – no advantage over NCPAP
» Chang HY et al; Pediatr Res; 2011

78. Neurally Adjusted Ventilatory Assist (NAVA)
• Electrical activity of the diaphragm (Edi) is used for
controlling ventilation in Neurally Adjusted Ventilatory
Assist
• NAVA ventilation mode may be used both as invasive
and non-invasive ventilation
• Timing and amount of delivered pressure is controlled by
patient
• One condition must be met – spontaneous breathing

79. • Edi catheter (6 Fr) is introduced through nostril and
placed according to the formula
• Edi catheter positioning was adjusted by means of ECG
display
• After appropriate placement sufficient Edi signal could be
detected

80. From NAVA to NIV - NAVA

81. NAVA
NAVA level - set on ha base of
Peak Inspiratory Pressure
applied in the previous ventilation mode

82. NIV - NAVA

83. HFNC – high flow nasal cannulae
• Flow rates exceeding 1L/min
– Initial support for early respiratory distress
– Postextubation support
– Step-down therapy from NCPAP
• HFNC interfaces
– Vapotherm
– Optiflow (pressure- relief valve in circuit)
• Open systems with leak at the nose and mouth
• Heated and humidified gas, blending and oxygen and air

84. HFNC – high flow nasal cannulae
• Pressure generated – unpredictable
– 0,3 cm outer diameter, flow rate 2L/min
• Mean esophageal pressure – 9,8 cm H2O
» Locke RG; pediatrics, 1993
– Recent studies
• Pressure ≤ NCPAP
» Kubica ZJ et al; Pediatrics 2008
» Spence KL et al.; J Perinatol; 2008
» Wilkinson DJ et al.; J Perinatol: 2008

85. How to use NIV ?

86. How much supporting pressure should be used
•NIPPV
•PIP as on MV or slighty
above
•Respiratory rate – 20-40
Davis PG: 2003; Cochrane Database Rev; CD000143

87. Suggested Weaning Guidelines During Nasal Ventilation
• Wean every 6–12 h
• Wean PIP first
• When PIP is at 10, then wean rate
• When rate is at 10, wean to NCPAP
• When patient is stable
– NCPAP of ± 5 cm H2O for 6–12 h
• wean to heated nasal cannula with flow rates of < 2 LPM.

88. Contraindication to NIV
• Progressive respiratory faillure or with poor respiratory drive
– High oxygen requirement
– PCO2 > 60mmHg
– pH < 7,25
– Apnea, bradycardia, desaturation do not responded to NCPAP
• Congenital malformations
– Choanal atresia
– Cleft plate
– Congenital diaphragmatic hernia
– Tracheoesophageal fistula
– Gastroschisis
• Severe cardiovascular instability

89. NIPPV - Complications
• Malpositioned nasal cannulae
– Variable flow CPAP system
– Airway obstruction by secretion
• Inadvertent PEEP – air leaks
– High ventilatory rate
– Too short expiratory time
– Minimal or no lung disease (high compliance)
• Carbon dioxide retention
– Alveolar overdistantion
• Increase work of breathing, PVR↑, CO↓
• Decrease urine output
– Too short expiratory time

90. NIPPV - Complications
• Decreased gastrointestinal blood flow - „CPAP belly”
– Abdominal distention
• Placement of orogastric tube
– NEC – not confirmed
– Gastric perforation - not confirmed
• Skin trauma Fischer C et al (Switzerland). Arch Dis Child 95: F447-F451; 2010

91. Summary
• NCPAP reduces respiratory instability and the need for
extra support after intubation
• NCAP reduces the rate of apnea
• NIPPV may augment the benefits of NCPAP
• Binasal prongs are better than single nasal prongs
• Used NCPAP after delivery may prevent or at least
diminish respiratory distress

92. • It does not matter what ventilator we choose but …
• How to provide respiratory support

93. • The art of medicine is to achieve optimal lung volume in
neonates with respiratory disorders
• CPAP is one method many clinicians believe best
achieves optimal lung inflation with resultant good
oxygenation and ventilation without the use of an
endotracheal tube

94. ECMO – instead of ventilators?
• Low volume of circuit
• Possibility to provide without hyalinization and trough
thin cannulas
• Even then Optimal Lung Volume in neonates with
surfactant insufficiency will be necessary

95. Thank you…

96. „Bubble” CPAP vs CPAP with Mechanical Ventilator
(12 PT infants; <1500g)
Mean (+/- SD) Pressure (cmH 2O)
Ventilator: open symbols
12 Bubble: solid symbols
10
8 8
(set NCPAP)
6
4 4
2 No Leak
4 6 8 10 12
Bias Flow (Liters/min)
Kahn et al, Pediatrics, 2007