1. Lower airway disease in children and neonates
1) Typical features of neonatal and pediatric lung disease
2) Pediatric mechanical ventilation: Anything special to know?
Conventional vs high frequency ventilation

2. Acute respiratory failure in childhoood
pump failure
neuromuscular diseases
central nervous system disease
lung failure
primary lung disease (inflammatory)
of various etiology
IRDS (infant) / ARDS (adult = acute)
elevated PaCO2
minimal intrapulmonary shunting
easily managed with
conventional ventilation settings
diffuse atelectasis, permeability oedema
low lung compliance, and
intrapulmonary shunting (hypoxemia)

3. Typical features of neonatal and pediatric lung disease:
Infant respiratory distress syndrome
Acute hypoxic respiratory failure (incl. ARDS)
Bronchiolitis (RSV-Bronchopneumonia)

4. Clinical characteristics of infant RDS
Polypnea resp. freq. > 60 / Min
Intercostal Retractions use of accessory muscles
Grunting glottis closure at end-expiration
Cyanosis intra pulmonary shunting

5. HMD
wet lung
congenital pneumonia
meconial aspiration

6. Neonate at near-term or term
Preterm infant
LUNG IMMATURITY
Surfactant deficit
ASPHYXIE, SHOCK, ACIDOSIS
Neonate at near-term or term

8. Normal lung aereation, thin septa
Generalized atelectasis, leukocyte infiltration,
thick septa,
hyaline membranes

9. Medical developments in the treatment of infant RDS
Mortality
In the year 2000:
Incidence of BPD = 26% < 1500g
Lee, Canadian Network, Pediatrics 2000 O2
Mechanical
Ventilation
Antenatal steroids
CPAP
Exogeneous
Surfactant

10. Treatment-Concept No 1: Lung-Maturation

11. (surfactant depleted lung)
D V
Reduced pulmonary compliance:
D P
Normal lung
ALI
RDS at birth
(surfactant depleted lung)
Volume (l)
severe
(A)RDS
Airway pressure (cmH2O) 11 9

12. Concept No 2: Open the lung and keep it open
T --> Surfactant

13. Surfactant as a recruitment agent
pre
post
Volume
Pressure
PEEP
PIP
PEEP
PIP
Kelly E Pediatr Pulmonol 1993;15:225-30

14. Bronchopulmonary dysplasia
Mortality
Bronchopulmonary dysplasia
Soll RF (Cochrane Database) 2002

15. MRI signal intensity from non-dependent to dependent regions
The water burden of the lung makes the lung of the preterm infant,
despite surfactant treatment,vulnerable to VILI
4-day-old, 26-week gestation infant
2-day-old, 38-week gestation infant
Adams EW AJRCCM 2002; 166:397–402

16. Concept No 2: Open the lung and keep it open
T --> Surfactant
P --> positive
airway
pressures:
- CPAP
- CMV / HFO

17. VILI prevention: Avoidance of shear, overdistension,
cyclic stress and high intrathoracic pressures
High PEEP
Pressure
limitation +

18. Acute respiratory failure in childhoood
Preterm infant
Hyaline membrane disease
= infant RDS
Lung immaturity
Congenital pneumonia
acquired lung diseases:
nosocomial pneumonia
bronchiolitis
sepsis
Newborn (at term)
Congenital pneumonia
Meconium aspiration
Malformations:
Lung hypoplasia, CDH
acquired lung diseases:
nosocomial pneumonia
bronchiolitis
sepsis

19. Acute respiratory failure in childhoood
Infant (1- 12 months)
sepsis-syndrome
infectious pneumonia
(RSV-bronchiolitis)
non infectious pneumonia
- inhalational injury
circulatory arrest
Preschool age
sepsis-syndrome
infectious pneumonia
(RSV-bronchiolitis)
non infectious pneumonia
- foreign body aspiration
- inhalational injury
- drowning
trauma
circulatory arrest

20. Common pathogens for respiratory infections:
Neonatal period: group B beta-hemolytic streptococci (GBS)
gram negative enteric bacilli (E.coli)
Infants and viral (especially RSV)
small children:
bacterial: Streptococcus pneumoniae
mixed infections (e.g., viral-bacterial) can occur in 16-34% of patients

21. Acute viral bronchiolitis
Respiratory syncytial virus (RSV) in > 80 % of all cases
Parainfluenza I et III, Adenovirus, Rhinovirus
Transmission: surface, droplets
Variations: seasonal and biannual (?)
Primo-infection during the first year of life: 70%
At the age of 2 years: 100%.

22. Acute Bronchiolitis: Epidemiology
Classical resp. tract infection of the infant (up to 2 years)
Hospitalisation required in:
1-3% normal infants
10-25% infants prematurely born
Prematurity = single most important risk factor for
both hypoxemia and respiratory failure in RSV bronchiolitis
15-25% infants with cardiac malformations
15-45 % infnats with bronchopulmonary dysplasia
Prevention: Passiv Immunization
Maternal antibodies
Monoclonal antibodies: Palivizumab (Synagis) 15mg/Kg im q 1 month

23. Cellular
(lymphocytic)
infiltration
+ edema
Normal
bronchioli

24. Bronchiolitis: Physiopathology~ 4
Edema + infiltration increased resistance mucus +/- cellular debris
1/R
Insp. resist. < exp. resist.
Insp. retractions
Polypnea
Exp. wheezing
Hyperinflation
The child will try to maintain
normal minute ventilation
Respiratory fatigue
Insuffisance respiratoire
Hypercapny
(= first warning sign)
Hypoxemia occurs later
(= vital warning sign)
PaO2 mmHg
PaCO2 mmHg 80 40 50 60
F resp
80 F resp

25. Typical hyperinflation in bronchiolitis

26. Hyperinflation and atelectasis in bronchiolitis

27. Acute Bronchiolitis: Treatment
Humidification O2
Surveillance and respiratory monitoring
Bronchodilators b-mimetics +/-
ipratropium bromide
inhaled adrenaline
Antiviral therapy Ribavarin
- acute effect ?,
- longterm benefit Chest 2002; 122:935-9
Antiinflammatory tx: Steroides
- acute phase: shortens length of hospital stay but not duration of ICU-stay or mechanical ventilation Thorax 1997; 52:634-7
- not effective on long term outcome Pediatr Pulmonol 2000; 30:92-96
CPAP, non-invasive ventilation, intubation + ev. HFO

28. 1) Typical features of neonatal and pediatric lung disease
2) Pediatric mechanical ventilation: Anything special to know?
Conventional vs high frequency ventilation

29. From the newborn to the adult: Physiology
Chest wall compliance
FRC
Elastic Recoil
Rib cage distortion
Pleural pressure distortion

31. From the newborn to the adult: Crs
chest wall
chest wall
Newborn
Adult
lung
lung
Agostini J Appl Physiol 1959; 14:

32. From the newborn to the adult: FRC
chest wall
chest wall
Newborn
Adult
lung
lung
Agostini J Appl Physiol 1959; 14:

33. An intubated neonate or infant is always ventilated with PEEP
To maintain a reasonable EELV the neonate closes his glottis at the end of expiration (to avoid lung unit closure)
Therefore:
An intubated neonate or infant
is always ventilated with PEEP

34. From the newborn to the adult: Paw effect
chest wall
chest wall
Newborn
EELV
above FRC
Adult
EELV
above FRC
lung
lung
Agostini J Appl Physiol 1959; 14:

35. normal
lung compliance
decreased
lung compliance

36. How much pressure in small children?

37. Ventilator induced lung injury
Adults and children: Acute respiratory distress syndrome (ARDS)
Ventilator induced lung injury
Mechanical
ventilation
Oxygenation
Lung volumes
Pulm. compliance
Mortality: %
CLD: %
Newborn: Infant respiratory distress syndrome (iRDS)

38. (surfactant depleted lung)
Allowable Vt and disease severity
Normal lung
ALI
(surfactant depleted lung)
Volume (l)
severe
(A)RDS
To place tidal breathing within this safe window during conventional ventilation can become difficult or almost impossible in the severly diseased lung which shows poor compliance with a flattened pressure-volume curve. In the lung with mild lung injury or only slightly decreased compliance such as in hyaline membrane disease at birth it will be relatively easy because larger tidal volumes (5 to maximally 7 ml/kg ) can be allowed.
Airway pressure (cmH2O)

39. 1) Typical features of neonatal and pediatric lung disease
2) Pediatric mechanical ventilation: Anything special to know?
Conventional vs high frequency ventilation

40. Rationale for HFOV-based lung protective strategies
CMV
HFOV
CMV
HFOV
HFOV uses very small VTs.
This allows the use of higher EELVs to achieve greater levels of lung recruitment while avoiding injury from excessive EILV.
2. Respiratory rates with HFOV are much higher than with CV.
This allows the maintenance of normal or near-normal PaCO2 levels, even with very small Vts.

41. The concept of volume recruitment during HFO
Suzuki H Acta Pediatr Japan 1992; 34:

42. Elective HFOV vs CMV in preterm infants: Outcome 28 days
All trials
Favors HFO
Favors CMV
With volume recruitment

43. First Intention HFO with early lung volume recruitment
Retrospective study with historical cohort in preterm infants with RDS,
mean GA = 27.7 (± 1.9), < 32 w / mean BW = 970 (± 250), < 1200 g
Survival and CLD Morbidity
all patients
HFO (n=32)
CMV (n=39)
p - value
survivors to 30 days
HFO (n=27)
CMV (n=35)
Ventilation (days)
5 (3-6)
14 (6-23) *
Oxygen dependency (FiO2 > 0.21) (days)
12 (4-17)
51 (20-60)
< *
Oxygen at 28 d, no (%)
6 (22)
22 (63)
0.002 #
survivors to 36 weeks PCA
CMV (n=34)
CLD; Oxygen > 36 weeks PCA, no (%)
0 (0)
12 (35)
Values are given as the median (95% CI) or the number (percentage) of patients; * Mantel-Cox log-rank; # Fisher's exact #
Rimensberger PC et al. Pediatrics 2000; 105:

44. MOAT II: Overall Survival
HFOV CV N
P/F (37) 111 (42)
30d p=0.057
90d p=0.078
HFOV CV
Derdak S Am J Respir Crit Care Med 2002; 166:801–808

45. MOAT II: Survival - PIP  38 cmH20 (post-hoc)
30d p=0.019
90d p=0.026
HFOV CV
European
HFV-Meeting
2001

46. Conclusions Although there exist some special respiratory pathologies
in early childhood, treatment concepts are not to much
different from the one in adult patients.
However, it is important to recognize early signs of
respiratory distress in infants and small children, because
this patients are at high risk for a sudden cardiac arrest.