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Minimizing Lung Damage During
Respiratory Support
Care of the Sick Newborn 2015
Eduardo Bancalari MD
University of Miami
Miller School of Medicine
Jackson Memorial Hospital
University of Miami Jackson Memorial Medical Center
0
20
40
60
80
100
%
23 24 25 26 27 28
Gestational Age (wks)
NICHD NETWORK
Bronchopulmonary Dysplasia (O2 at 36 wks PMA)
Years 2003-2007
What Can Damage The Immature Lung
• Over distension
Excessive VT : PIP – PEEP
Excessive FRC: PEEP, gas trapping
Prolonged inspiratory time
• Low volume, loss of FRC: Insufficient PEEP
• Oxidative damage
• Infection: Pulmonary, systemic
• Increased PBF-PE : PDA, excessive fluid administration
• Inadequate conditioning of the inspired gas:
Temperature, humidity
How Can We Protect The Immature Lung ?
• Accelerate Maturation: Antenatal steroids
• Surfactant Replacement Prophylaxis vs Rescue?
• Gentle Ventilation Appropriate tidal volume / Volume target/ HFV Adequate PEEP Patient Triggered Ventilation
Permissive hypercapnia?
• Avoid High Inspired Oxygen Concentrations
• Avoid Invasive Ventilation: CPAP , N-IPPV
Respiratory support strategies to prevent BPD • Respiratory support during resuscitation : Ventilation,
Oxygen • NCPAP vs intubation after birth • NIPPV vs IPPV in RDS • Synchronized ventilation • Permissive hypercapnia • HFV: HFO, HFJV • Volume targeting • Oxygen targets
2
Does variation in respiratory management in NICUs
explain differences in CLD? Van Marter. Pediatrics 2000, 105,1194-1201
Compared Columbia NY with 2 Boston hospitals.
Infants < 1501g in 1991 - 1993.
Boston Columbia
n=341 n=100
Ventilation 75% 29%
Surfactant 45% 10%
Oxygen at 36 wks 22% 4%
Boston Columbia
n=341 n=100
Ventilation 75% 29%
Surfactant 45% 10%
Do differences in delivery room intubation explain different
rates of BPD between hospitals?
Gagliardi, L et al. Arch Child Fetal Neonatal Ed. 2011;96:F30-F35
IPPV >24h = OR for BPD 2.4
IPPV >7d = OR for BPD 14.9
NCPAP vs. IPPV BPD or Death
Fischer S H, and Buhrer C, Pediatrics Nov 2013
Death/BPD IPPV Surfactant CPAP MV-Surf CPAP MV-Surf CPAP MV-Surf
COIN 25-28 wks
34% 39% 58.7% 100% 38% 77%
SUPPORT 24-28 wks
49% 54% 83.1% 24.8 d
99.7% 27.7d
67% 99%
VON (CPAP) 26-30 wks
31% 37% 52% 96% 46% 99%
VON (ISX) 29% 37% 59% 96% 98% 99%
Early CPAP vs. IPPV in extremely low gestational age newborns
0
10
20
30
40
50
60
70
80
90
100
% In
fan
ts in
resp
irato
ry c
are
gro
up
s
500-599 600-699 700-799 800-899 900-999 1000-1099 1100-1199 1200-1250 <1250
Birth weight (g)
Distribution of infants (%) into respiratory care groups by birth
weights
CPAP-started (% of total) CPAP-success (% of CPAP-started) CPAP-success (% of total)
Adapted from Ammari et al. J Pediatr. 2005; 147(3): 341-347
Is Nasal Ventilation a Better
Alternative?
• Possible mechanisms of action:
– Increase in Vt and Ve
– Upper airway stimulation may reduce apnea
– Higher mean airway pressure: Better lung stability and
gas exchange
– Reduced dead space: Clears exhaled gas from proximal
airway
3
Nasal Ventilation
Physiologic effects
• Decreases apnea
• Improves ventilation- gas exchange
• Increases lung volume- improves
oxygenation
• Decreases respiratory effort
• Decreases chest wall distortion
Non Invasive Respiratory Support - Conclusions
Many very premature infants can be managed with NCPAP or NIPPV from birth
It is difficult to predict which infants will fail and require intubation and mechanical ventilation
Success depends on gestational age, degree of lung disease, respiratory drive, and team’s attitude and skills
Use of NIPPV instead of CPAP may reduce the number of infants that need intubation and shortens the duration of MV
Early NCPAP or NIPPV may delay administration of surfactant in infants with RDS and worsen their evolution
The evidence that non invasive respiratory support improves short or long term outcome in ELBW infants is not very compeling
Depressed - Poor resp effort
ET tube IPPV
Surfactant if RDS
When stable extubate
to NCPAP or N-IMV
Active - Good resp effort
Approach to VLBWI in the DR
Start NCPAP or N-IMV
Deterioration,
Increasing FiO2,
PaCO2, Apnea
ET tube-IPPV-
Surfactant if RDS
When stable extubate
to NCPAP or N-IMV
Stable-Continue
NCPAP
Newer Modalities of Mechanical Ventilation
• Patient Triggered (Synchronized Ventilation) S-IMV Assist control Pressure support Proportional assist ventilation (PAV) NAVA (Neurally adjusted ventilatory assist)
• Volume targeted ventilation
• Experimental:
Closed Loop FiO2 control
Continuous flow or distal tracheal ventilation
Targeted minute ventilation
CONTROLLED IPPV
(Apnea or M. Relaxants)
IMV - SIMV - AC - PSV - PAV
NON INVASIVE SUPPORT
Nasal CPAP - Nasal IPPV
Ve
ntilato
r D
ep
en
de
nc
e
ASSISTED VENTILATION
• Duration of ventilation
Synchronized vs. Conventional
Ventilation
Greenough and Dimitriou
Cochrane Database 2008
4
Firme SRE et al. Pediatr Pulmonol 2005;40(1):9-14
IMV vs. SIMV and Hypoxemia in Preterm Infants 20cmH2O
Paw
0 16 ml
VT
0
0.8 s
SIMV (20 b/m)
SIMV (10 b/m) + PS 20cmH2O
Paw
0 16 ml
VT
0
Time (Days)
0 5 10 15 20 25 30
Ven
tila
tor
Dep
enden
cy (
%)
0
20
40
60
80
100SIMV+PS
SIMV
Time to extubation
On MV at day 28
SIMV 69%
SIMV+PS 47%
Reyes et al. Pediatrics October 2006
Ventilator and Oxygen Dependency
700-1000g BW strata SIMV SIMV+PS
Days on MV (median, 25thand 75th percentile)
25 (8-47)
15 (6-23)
Days on oxygen (median, 25th and 75th percentile)
58 (44-87)
41 (34-51)*
On oxygen at 36w PMA 38
17%
Reyes et al. Pediatrics October 2006
*P 0.034
Pressure Support Ventilation
• Patient maintains spontaneous respiratory effort
• Duration of inspiration and expiration determined by the patient
• Spontaneous breaths can be unloaded as necessary to maintain Vt and Ve
• Volume loss can be prevented by few larger SIMV breaths
• Weaning is accomplished by gradual reduction of the pressure support
Limitations of PTV
• Low Sensitivity of trigger
Lack of trigger
Trigger delay: Mechanical breath extending
into expiration causing active expiration
• Excessive sensitivity to trigger artifacts:
Auto triggering
• Early termination, mechanical inspiration too
short: insufficient tidal volume
• Added dead space:CO2 retention
5
Volume Targeted
Ventilation
No. of studies
No. of Infants
Statistical method Effect size
Duration of IPPV (log data)
5 381 Mean Difference (IV,
Fixed, 95% CI) -0.08 [-0.16, -0.00]
Wheeler K et al. Cochrane Database of Systematic Reviews 2010, Issue 11.
Volume-targeted vs. pressure limited ventilation: Duration of IPPV
VTV versus PLV: Death or BPD (36 weeks)
Significant difference Death or BPD 32% v 43%
RR 0.73 95% CI 0.57 to 0.93, NNT 8
Wheeler K et al Neonatology 2011
VTV versus PLV: Pneumothorax
Significant difference Pneumothorax 4% v 10%
RR 0.46, 95% CI 0.25 - 0.84
Wheeler K et al Neonatology 2011
VTV versus PLV: Grade 3/4 IVH or PVL
Significant difference PVL or grade 3-4 IVH 8% v 16%
RR 0.48, 95% CI 0.28 - 0.84
Wheeler K et al Neonatology 2011
6
Peng WS et al. Arch Dis Child Fetal Neonatal Ed 2013;0:F1–F8. doi:10.1136/archdischild-2013-304613
BPD
Volume-targeted ventilation is more suitable than pressure-limited ventilation for preterm infants: a systematic review and meta-analysis
VG
Volume targeted ventilation
• Rationale: More consistent Vt – avoids excessive volumes
Automatic weaning of pressure
Shorter duration of mechanical ventilation
Reduces duration of hypoxemia episodes
Reduces death or BPD
• Limitations: Leaks around the endotracheal tube
Poor estimation of Vt:
Different inspiratory and expiratory Vt with leaks
Volume loss in the ventilator circuit: Vt delivered by ventilator larger than patient Vt
Cools F, Henderson-Smart DJ. Cochrane Database of Systematic Reviews 2009
OXYGEN DAMAGE
Contrasting light microphotographs of lung parenchyma of rats exposed to room air and O2
Shaffer SG, et al. Pediatr Res. 1987;21:14-20.
Hyperoxia Disrupts Alveolar Development
Room air O2
7
Are New Ventilation Modalities
Associated With Better
Outcome?
TEN YEAR TRENDS IN NEONATAL ASSISTED VENTILATION
Rich W, et al: Journal of Perinatology 2003, 23:660
0
4
8
12
16
20
24
28
32
36
40
44
48
Incid
en
ce (
%)
1994 1995 1996 1997 1998 1999 2000 2001 2002
Year
Unadjusted annual rates for GA <29 weeks (n = 1441)
BPD Severe BPD
Smith et al. J Pediatr. April 2005; 146(4):469-473
“Miami Neonatology 2015” &
Workshop:
“Advances in Neonatal Respiratory Care”
November 11 – November 14, 2015
Fontainebleau, Miami Beach
Speakers Topics
http://www.miamineonatology.com
39th Annual International Conference
• Robert “Bob” Christensen, MD
• Scott C. Denne, MD
• Terrie Eleanor Inder, MD, M.B.CH.B.
• Julie R. Ingelfinger, MD
• Shahab Noori , MD, RDCS
• Saroj Saigal, MD, FRCP
• Pablo Sanchez, MD
• Umberto Simeoni, MD
• Sergio Stagno, MD
• Anton H van Kaam, MD, PhD
• Myra Wyckoff, MD
• Jill L. Maron, MD, MPH
• Thrombocytopenia in the NICU
• Evidence-based NICU transfusion guidelines
• Growing extremely premature infants in the NICU
• Providing enteral nutrition to extremely premature
• Influence of the environment and experience on brain development
• To MRI or not to MRI at term for the preterm infant
• Acute kidney injury (AKI) in the neonatal period
• The neonate with CAKUT
• Diagnosis and Management of Neonatal Hypotension and Shock
• Pathophysiology of P/IVH in the very preterm neonate
• Lifetime perspectives of former very premature infants
• Quality of life of former premature infants
• Antimicrobial Stewardship in NICU
• Early nutrition and the risk for long term disease
• Extreme preterm birth and medical decision making
• Perinatal viral infections, new developments on an old challenge
• High frequency ventilation
• Lung protective ventilation using conventional modes
• 2015 New Neonatal Resuscitation Guidelines
• Use of monitoring and Epinephrine in the DR