Non-invasive positive pressure ventilation in the neonate

Peter C. RimensbergerPediatric and Neonatal ICU

University Hospital of GenevaSwitzerland

In the year 2008: BPD incidence = 35% < 29 wks COIN-trial, NEJM 2008

COIN-trial

610 infants, 25-to-28-weeks’ gestation, randomized toCPAP intubation + ventilation

at 5 minutes after birth

Elastic work of breathing

Adult

Infant

Infant(Reduced Compliance)

Volume(%VC)

Volume(%VC)

Volume(%VC)

Pressure

ThoraxLungsChest wallWork = P * V

ACB: Move the chest wall from the resting position

AXC: Overcome resistive forces

Inward distortion of the rib cage on the volume displaced by the diaphragma

Innefficient ventilation and waist of work

Thoraco-abdominal Asynchrony(the noncoincident motion of the rib cage and abdomen during breathing)

If the rib cage is sucked in or retracted as abdominal excursions occur (e.g., in upper airway obstruction),

or the abdomen is retracted as the rib cage expands (e.g., diaphragmatic paralysis)

Prisk GK Pediatric Pulmonology 2002; 34:462–472

25 weeks: Abdominal (red) & Chest Wall (green) Movements Synchronized NIPPV: Better ventilation

NCPAP NIPPV

Courtesy of Simon Bignall

Thoracoabdominal Asynchrony Synchrony

SNIPPV1) To avoid the need for endotracheal intubation in preterm infants with

respiratory failureBarrington KJ Pediatrics 2001; 107: 638–41 (RCT)De Paoli AG Acta Paediatrica 2003; 92: 70–5 (review and meta-analysis)Khalaf MN Pediatrics 2001; 108: 13–7 (RCT)Santin R Perinatol 2004; 24: 487–93 (prospective observational study)Friedlich P Perinat 1999; 19: 413 (RCT)

2) It has been shown to be particularly effective in decreasing reintubation when compared with nasal CPAP as an extubation mode Barrington KJ Pediatrics 2001; 107: 638–41 (RCT)Khalaf MN Pediatrics 2001; 108: 13–7 (RCT)Friedlich P Perinat 1999; 19: 413 (RCT)

3) SNIPPV has been used as an alternative to continued endotracheal mechanical ventilation after surfactant therapy in 28- to 34-week gestation infants with respiratory distress syndrome Santin R Perinatol 2004; 24: 487–93 (prospective observational study)

4) Work of breathing has also been shown to be decreased with the use of SNIPPV compared to nasal CPAP Kiciman NM Pediatr Pulmonol 1998; 25: 175–81

Reintubation after extubation:

A prospective RCT comparing SNIPPV vs NCPAP

(Khalaf MN, et al. Pediatrics 2001;108:13-17)

Criteria for extubation: 1. MAP = 4-6 cm H2O 2. IMV 25/minute 3. PIP 16 cm H2O 4. PEEP 5 cm H2O 5. FiO2 0.35 6. Aminophylline level 8 mg/L 7. Hematocrit 40%

After extubation: 1. SNIPPV: PIP +4, same IMV-PEEP 2. NCPAP: 4- 6 3. FiO2: O2 saturations 90-96%

Criteria for re-intubation: 1. pH < 7.25 2. PaCO2 > 60 mmHg 3. PaO2 < 50 mmHg despite a FiO2 of 0.7 4. A single episode of apnea requiring bag and mask resuscitation 5. Frequent ( 3/hr) apnea/bradycardia spells 6. Multiple ( 3/hr) desaturation episodes despite a FiO2 of 1.0

SNIPPV (n =34)

NCPAP (n =30)

p value

Age at study (d) 4 (1 -83) 2.5 (1 -106) 0.95

Wt. at study (gm) 1110 55 1200 75 0.32

Pre -MAP (cm H2O) 4.9 0.2 5.1 0.2 0.38

Pre -FiO2 0.30 0.02 0.30 0.01 0.84

AR (cm/H2O/L/s) 169 16 205 21 0.18

LC (ml/cmH 2O) 0.74 0.02 0.8 0.1 0.57

Post -pH 7.36 + 0.03 7.34 + 0.02 0.14

Post -CO 2 (mmHg) 37 + 1.0 40 + 2.0 0.06

Apnea (n) 2.24 0.8 2.03 0.7 0.84 Success (n, %) 32 (94) 18 (60) < 0.01

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Reintubation after extubation:

(Khalaf MN, et al. Pediatrics 2001;108:13-17)

A Prospective Observational Pilot Study: SNIPPV as a Primary Mode of Ventilation In Infants > or = 28 Weeks with RDS

(Santin RS, et al. J Perinatol 2004;24:487-93)

SNIPPV (n=24)

CV (n=35) P value

Birth weight (grams) * 1582 ± 77 1511 ± 103 0.92

Gestational age (weeks) * 31.2 ± 0.5 31.0 ± 0.4 0.89

Gender (male, n, %) 15 (63) 22(62) 0.88

Antenatal steroids (n, %) 18 (75) 24 (68) 0.90

Apgar at 5 minutes (median) 8 8 0.87

Age at surfactant instillation (h)* 3.1 ± 1.4 2.7 ± 0.49 0.49

Mean ± SEM

A Prospective Observational Pilot Study: SNIPPV as a Primary Mode of Ventilation In Infants > or = 28 Weeks with RDS

(Santin RS, et al. J Perinatol 2004;24:487-93)

SNIPPV (n=24)

CV (n=35)

p value

OI pre-surfactant instillation (cm H2O) 6.0 ± 1.0 5.5 ± 0.6 0.67

Duration of endotracheal intubation (days) 0.3 ± 0.0 2.40 ± 0.4 0.001

Duration of SNIPPV (days) 2.8 ± 0.4 3.1 ± 0.7 0.68

Duration of CPAP (days) 0.3 ± 0.3 0.2 ± 0.1 0.71

Duration of nasal cannula (days) 3.8 ± 1.5 5.1 ± 1.3 0.3

Duration of supplemental O2 (days) 8.2 ± 3.3 15.0 ± 3.2 0.04

Duration of parenteral nutrition (days) 8.4 ± 0.8 12.1 ± 1.6 0.02

Length of stay (days) 29.1 ± 3.3 37.5 ± 3.0 0.04

Mean ± SEMOI: Oxygenation Index

Kugelmann A J Pediatr 2007;150:521-6

NIMV versus NCPAP for Respiratory Distress Syndrome: A Randomized, Controlled, Prospective Study

Kugelmann A J Pediatr 2007;150:521-6

Infants treated initially with NIPPV needed less ETT ventilation than infants treated with NCPAP.

Infants treated with NIPPV had a decreased incidence of BPD compared with those treated with NCPAP

A RANDOMIZED CONTROLLED TRIAL OF SYNCHRONIZED NASAL INTERMITTENT POSITIVE PRESSURE (SNIPPV) VENTILATION IN RDS

(Bhandari V, et al. J Perinatol 2007;27:697-703)

SURF-N-SAVE STUDY: HYPOTHESIS

Primary mode SNIPPV (defined as its use in the acute phase of

RDS, following the administration of the first dose of surfactant)

initiated shortly after birth would decrease the incidence of BPD

and/or death in smaller premature babies when compared to

conventional endotracheal mode of ventilation.

INCLUSION CRITERIA 1. <32 weeks gestational age.

2. Birth weight 600-1250 grams

3. RDS requiring intubation and surfactant therapy within one hour of birth. The need for intubation /surfactant was based on the following:

a. Fi02 > 0.4 to maintain Sa02 > 90%.

b. Chest radiograph consistent with RDS

EXCLUSION CRITERIA (any one)

1. Nasopharyngeal pathology.a. Choanal atresia.b. Cleft lip or palate.

2. Major congenital anomalies, especially thoracic or cardiac defects.

3. Clinical parameters for exclusion ninety minutes after initial surfactant therapy (approximately 2½ hours after birth).

a. Oxygenation index (OI=[(Fi02)(mean airway pressure)]/Pa02) > 9.

b. No indwelling arterial line.c. More than two isotonic fluid boluses.d. Continuous medication infusion for blood pressure support.e. Fi02 > 0.8.

A RANDOMIZED CONTROLLED TRIAL OF SYNCHRONIZED NASAL INTERMITTENT POSITIVE PRESSURE (SNIPPV) VENTILATION IN RDS

(Bhandari V, et al. J Perinatol 2007;27:697-703)

A RANDOMIZED CONTROLLED TRIAL OF SYNCHRONIZED NASAL INTERMITTENT POSITIVE PRESSURE (SNIPPV) VENTILATION IN RDS

(Bhandari V, et al. J Perinatol 2007;27:697-703)

Longterm Outcome: Mental or Psychomotor Developmental Intex

There were no statistically significant differences in the MDI (mean SD; CV (n=8) versus SNIPPV (n=7); 88.13 10.32 versus 81.43 17.54) or PDI (88.38 11.87 versus 84.29 19.47) scores in the infants, assessed at a median (25th –75th centile) corrected GA of 22 (20.5-24) months.

PrimaryOutcome:

Birth weight (grams)* 858 ± 27 915 ± 41 0.24

Gestational age (weeks)* 27.0 ± 0.4 26.9 ± 0.3 0.93

CV (n=21)

SNIPPV (n=20)

P value

BPD or Deaths (n, %) 11 (52) 4 (20) 0.03

BPD (n, %) 7 (33) 2 (10) 0.04

Deaths (n, %) 4 (19) 2 (10) 0.66

Air leaks (n, %) 1 (5) 1 (5) 1.0

PDA (n, %) 3 (14) 4 (20) 0.70 IVH (n, %) 6 (29) 6 (30) 1.0

PVL (n, %) 1 (5) 2 ( 10) 0.61

In the year 2008: BPD incidence = 35% < 29 wks COIN-trial, NEJM 2008

COIN-trial

610 infants, 25-to-28-weeks’ gestation, randomized toCPAP intubation + ventilation

at 5 minutes after birth

- As extubation mode

- To control apnea, avoiding extubation

- Primary mode (with or without surfactant use): more data needed

Strategizing SNIPPV

IMV

SIMV

Assist/Control

FSVPSV

Synchronization Principles

Graseby CapsuleInfant Flow Advanced

Viasys “ SIPAP”

Flow sensorGinevri “ Giulia”

SLE 5000

Babylog 8000

NAVA-system sensing of diaphragmatic electrical activity

Maquet “Servo-I”

SNIPPV: Trigger systems for synchronization

How to set Ti in a spontaneous breathing patient on a pressure support mode ?

Flow

Pressure

Tinsp.PIP

Pressure Control Pressure Support

Peak Flow

25%

“Flow termination criteria”

0 flow

Ti Te

PEEP

PS above PEEP

0 flow

?

Termination Sensitivity = Cycle-off Criteria

Flow

Peak Flow (100%)

TS 5%

Tinsp. (eff.)

Leak

Time

Set maximal Tinsp.

TS 30%

200 a.u.

10 seconds

Feeding, baby moving28 weeks, 1486g

Sleeping, 30 weeks, 1158 g

Sleeping, 30 weeks, 1205 g

Sleeping, 30 weeks, 1158 g

Baby awake, 28 weeks, 1486g

Sleeping, 30 weeks, 1205 g

Beck et al, PAS 2006

Neural breathing pattern in the preterm (room air, no vent)

1

2

3

Non-invasive neurally adjusted ventilatory assist (NAVA)

in rabbits with acute lung injury

Beck J et al. Intensive Care Med (2008) 34:316–323

Non-invasive neurally adjusted ventilatory assist (NAVA)

in rabbits with acute lung injury

Beck J et al. Intensive Care Med 2008; 34:316–323

baby 440 grams

baby 440 grams

1st experience

baby 440 grams

baby 440 grams

J.Beck ICM 2008

“NAVA can deliver assist in synchrony and proportionally to EAdi after extubation, with a leaky non-invasive interface”

Conclusions

Meta-Analysis: “NIPPV is a useful method of

augmenting the beneficial effects of NCPAP in

preterm infants…..reassuring absence of the

gastrointestinal side-effects that were reported in

previous case series.” (Cochrane Collaboration)

Issues to be solved

Patient selection

Indications

Synchronization during NIPPV