Ventilator Strategy To Prevent Chronic Lung disease

Ventilation Strategies toPrevent Chronic Lung disease

R. Adhi Teguh Perma Iskandar

Neonatal Division of Ciptomangunkusumo Hospital

AIMs

1. Ventilation strategies from delivery room to NICU to avoid CLD.

2. Optimal gas exchange, patient comfort, ventilator adjustment, weaning

3. Monitoring during mechanical ventilation

4. Manage troubleshooting

Introduction

Chronic lung disease is often used interchangeably with Bronchopulmonary Dysplasia

With the increasing of extreme preterm infants (< 28 weeks) survival the incidence of CLD increases as well

Incidence of CLD in preterm < 28 weeks in Asia is 25-56%

Infants with CLD will have prolonged hospital stays, high healthcare costs, and long term pulmonary and neurologic morbidity

We need ventilation strategies for high risk babies in order to reduce the long term morbidity of CLD

Siffel at al. J Matern Fetal Neonatal Med. 2019; 9:1-11

Hilgendorf. Am J Respir Cell Mol Biol 2014 ; 50(2): 233–245

Chronic Lung Disease

Chronic lung disease in preterm • Alveolar development arrest • Injury and Inflammations of the lung • Parenchymal and airway remodeling • Vascular growth arrest • Changed lung compliance, airway

resistence and V/Q missmatch

http://www.embryology.ch/dutch/rrespiratory/phasen07.htm

Chronic Lung Disease

Clin Perinatol 37 (2010) 273–293J Pediatr. 2018 June ; 197: 300–308

Risk Factors for CLD

Prenatal

• Maternal preeclampsia

• Lack of antenatal steroid

• Chorioamnionitis

• Fetal growth restriction

• Extremely Preterminfants (< 28 weeks)

Postnatal

• Surfactant deficiency

• Patent ductus arteriosus

• Early /late onset sepsis

• Ventilated babies

Predictor of BPD, Clin Perinatol.2012;39(3):585-61

Strategies to avoid CLD

• Antenatal steroid

• Use Non of invasive ventilation

• Caffeine

• Postnatal Steroid

• Surfactant replacement

• Inhaled Nitric oxide

• Vitamin A

• Appropriate PDA management

• Fluid restriction

• Good nutrition to promote growth

• Lung protective strategies

Semin Perinatol 2016; 40(6): 348-355

Avoiding lung injury in delivery room (1)

Support effective

ventilation

Effective IPPV for

apneic or irregular breathing

Early CPAP for regular breathing

infants

Use of targeted SpO2 to

guide FiO2

Sustained inflation

(Preterm ?)

Respiratoryfunction

monitoring(in research)

Avoiding lung injury in delivery room (2)Warm and humidified gas and early surfactant

A recent meta analysis of early (within 2 hours) versus delayed surfactant treatment concluded that risks of

mortality (RR 0.84; 95% CI 0.74–0.95), air leak (RR 0.61; 95% CI 0.48–0.78), chronic lung disease (RR 0.69; 95% CI 0.55– 0.86), and chronic lung disease or death (RR 0.83; 95% CI 0.75–0.91)

There were no differences in other complications of prematurity.

Soll R, Cochrane systematic review 2012

Avoiding lung injury during transport

Use of transport ventilator especially for ELBW/extreme preterm

• Maintain stable pressure

• Avoid over or low tidal volume

• Provide warm and humidified gas

• Give appropriate FiO2

• Show real time lung dynamic

• Adjustment pressure or tidal volume

• HFO transport if indicated

Avoiding lung injury in NICU in ventilated babies

• Optimize lung function/ gas exchange

– Open the lung

– Keep the lung open

– Optimize tidal volume

• Optimize patient comfort and minimize work of breathing during ventilation

– Synchronization

– Pain management

– Manage troubleshooting

• Reduce lung injury

– Ventilator adjustment according to lung condition

– Ventilator adjustment according to blood gas analysis (Permissive hypercapnia)

– Use more lung friendly ventilation (HFOV)

– Reduce the duration of ventilation (early weaning and extubation)

Ventilation Lung Injury (VILI)

VILI

Volutrauma

Atelectrauma

BiotraumaBarotrauma

Oxygen Toxicity

High Tidal Volume

Recurren alveolar collapse

High FiO2

High Positive Pressure

Inflammatory Cytokine Normal Lung

Lung injury

Clin Chest Med. 2016 December ; 37(4): 633–646.

Invasive Ventilation in NICU

Conventional Ventilator

FiO2(Oxygenation)

Mean airway Pressure

(Oxygenation)

Peak inspiratory

Pressure (PIP)

Positive end expiratory Pressure

Inspiration and expiration time

Minute Ventilation

(Removal CO2)

Delta Pressure (PIP – PEEP))

Frequency (rate/minute)

Invasive ventilation in NICUThe Effect of PEEP to open the alveolus

PIP 12 cmH20PEEP 2 cmH20

PIP 12 cmH20PEEP 6 cmH20

Optimal PEEP

Normal lung : PEEP of 3 cm H2O is adequate and PEEP of 6 cm H2O may result in overexpansion

Poorly compliant lungs PEEP levels of 8 to 10 cm achieve adequate alveolar recruitment

PEEP > 5 cm H2O due to underlying lung disease and the ETT bypassing the larynx.

Journal of Perinatology (2009) 29, 262–275Cochrane Database of Systematic Reviews 2019

How do we know over PEEP/overdistension?

• Chest rise

• Tachycardia

• Hypotension

• Anuria

Physical exam

• C20/C < 0.8

• Scalar flow graphics air trapping

Ventilator

• Blood gas analysis pCO2 rise

• Chest X Ray > 9 ribs

• Echo distended IVC

laboratory

Open lung strategies with conventional ventilator?

Step wise increase Mean Airway Pressure

Mean Airway Pressure = [PIP X Insp Time] + [PEEP X Eksp Time] Insp Time + Eskp Time

CDP= FRC

CT 1 CT 2

CT 3

Paw = CDPContinuous

Distending

Pressure =Mean

airway Pressure

Maneuver of Lung

Recruitment

Lung Recruitment Maneuver

• Using PTV+VTV or AC+VG mode

• Setting : Vte= 5 mL/kg

• Rate 50-60x/minute

• I:E = 1: 2

• Pmax = 5 + Pworking pressure (cmH2O)

• PEEP = 5 cmH20 increase PEEP 0,2-0,5 cmH20 every 5 minutes

• Lower FiO2 if SpO2 > 95%

Castoldi. Am J Perinatol. 28:521-528 2011

Castoldi. Am J Perinatol. 28:521-528 2011

0

10

20

30

40

50

60

70

80

90

100

75

80

85

90

95

100

5 5.56.5 7.0 7,5

8.07,5

7.06,5 5,0

4,55.0

SpO2FiO2

Boy; GA 26 mg; BW 750 g

%%

PEEP

SpO2FiO2

Time

Optimize tidal volumeWhat mode should we choose?

• Can detect breathing effort even small

• Every breath should be supported• Synchronized patient breathing

with ventilator• Enough inspiration time to let

alveoli open• Keep every breath within safe

tidal volume (4-6 mL/kg)

PTV + VTV

Flow trigger

Volume targeted

Time cyclesinchronized

Pressure regulated

Patient Triggered Ventilation + Volume Targeted Ventilation

Goldsmith JP, Karotkin EH. Introduction to assisted ventilation. In: Assisted ventilation in neonate. 5th ed. New York: Elsevier; 2011. p. 1–2.

Pinsp

P

PEEP

V

VT=10.6 ml VT=10 ml

VTset=6.5 ml

VT=8.9 ml VT=6.5 ml

Tekanan maks.

Vte set = 10,5 ml

P max 25 cmH20

Pmean

PEEP = 5 cmH20

Vt insp

VT = 6,5 ml VT = 8.5 ml VT = 10 ml VT = 10.2 ml

Tidal Volume for initial setting

Usia Gestasi Patologi Batasan Volume Tidal Tipikal (ml/kg)

Bayi Prematur Sindrom Gawat Napas (RDS) 4 – 5

Bayi Amat Sangat Prematur Sindrom Gawat Napas (RDS) 4 - 6

Bayi Prematur Tua Ketergantungan Ventilator 5 - 8

Bayi Cukup Bulan

Sindrom Aspirasi Mekonium 5 - 6

Hernia diafragma kongenital dengan tersangka hipoplasia paru

3.5 – 4.5 (disesuai dengan toleransi CO₂ < 80 mmHg)

Paru-paru normal, misal ensefalopati hipoksik iskemik (EHI)

~ 4

The Royal Woman’s Hospital. Policy, Guideline and Procedure Manual. 2017.

PTV + VTV versus SIMV + VTV

Parameter PTV + VTV SIMV+VTV significan

Heart Rate (beat/minute) 148±5 161±7 P<0,0001

Respiratory rate (breath/minute) 55,1±6 65±8 P<0,0001

Oxygen saturation (%) 95±2 91±3 P<0,0001

PIP (cmH20) 15±4,1 17±2.9 P<0,001 *

MAP (cmH20) 8,6±1,8 9,3±1,6 P<0,04*

Vte (mL) 5,2±0,5 3,2±1,8 P<0,0001#

Mve (mL) 328±5 319±74 NS&

*PTV vs Mandatory SIMV. #PTV vs Spontan SIMV & PTV VS all SIMV

22 infant26-33 weekersCross over designRDS babiesAC VG versus SIMV VGRR =30x/mnt, Vt =5 mL/KgBB

Keszler M, Abubakar K. J Perinato. 2005;25:638-42

Comfort during mechanical ventilation

Courtesy : Lily Rundjan, Novardian and Dian Anggur

Pain will increase oxygen demand, hyperventilation, provoked unsynchronized breathing

Patient comfort during mechanical ventilation will reduce lung injury and conserve energy for lung repair

Midline and prone position is recommended during neonatal ventilation

Sucrose, acetaminophen and morphine is used according to neonatal pain score

Minimal handling by delaying unnecessary procedure will make babies more comfortable

Asynchronized Breath Synchronized Breath

Vt

sec

Vt

sec

Higher Peak inspiratory pressure Variable tidal volume Higher oxygen requirement Higher use of sedation or opiate Higher episode of overventilation

Not easy to achieve Need continuous adjustment of

rise time, trigger and cycle thresholds

Needs sedation or muscle relaxant Sensor depended

Synchronization : Neuraly Adjusted Ventilatory Assist

Uses the Electrical Activity of the diaphragm (EDI) as a signal to trigger the mechanical ventilator breaths

NAVA improves patient-ventilator synchrony during invasive ventilation

Lower airway pressures and oxygen requirements are achieved with NAVA

Eur J Pediatr 2016 Sep;175(9):1175-1183

Trigger 0,2

L/mnt

0,5 det

0,36 det

1,0 det

Flow InspirasiL/mnt

10

2

Flow ekspirasiL/mnt

8

20%Flow cycle

Flow Max

Ventilator graphic and waveforms will tell us about lung dynamic

We should do periodical adjustment (Ins/Expiration time rise time trigger, PIP/Pmax, PEEP, tidal volume) in order to avoid lung injury

Ventilation adjustment (1)

Ventilation adjustment (2)

Ventilator parameters are adjusted according to blood gas analysis (pH, pCO2,pO2).

Ideal BGA : accurate, small blood volume, accurate, non/minimally invasive (heal prick) , bed side

Beware: abnormal blood gas result not always due to lung deterioration inadequate arterialization, dilution by heparin, over crying may need to repeat the blood gas

Hand held blood gas analyzer

Blood gas analysis for ventilation adjustment (3)

For very unstable babies, we need to do BGA more often risk of anemia, arterial line complication, risk of infection

Transcutaneous blood gas monitoring (TCM) non invasive, continuous blood gas monitoring, trend analysis / real time, reduced risk of anemia

The difference between TCM and blood gas analysis is around 5-6 mmHg

Acidosis respiratory with increasing pCO2-ptCO2 gap hemodynamic problem

Mucopadhay et al. Respir Care. 2016;61:96-7

The Royal Woman’s Hospital. Policy, Guideline and Procedure Manual. 2017.

Allowing pCO2 <60 mmHg as

long as pH > 7.25

Reducing increments of

Vte

Avoid Volutrauma

Trouble shooting for worsening situation (desaturation, chest retraction etc)

• Dislodgment • Obstruction : mucous, blood, clot• Pneumothorax : air leak syndrome, • Equipment error : need recalibration, out of gas, rain circuit, inappropriate

humidification, sensor • DiStended abdomen • Pain : crying, splinting, fighting• Leak : ETT’s Diameter • Oxygen delivery problem : Anemia, hypoperfusion, hypotension

• Shunting : pulmonary hypertension, PDA• Asincronization : inappropriate trigger and time cycle

High Frequency Oscillating Ventilation

High Frequency Ventilaton

FiO2 (Oxygenation)

Mean airway Pressure

(oxygenation)

Pmean

Minute Volume HFO

(ventilation)

Inspiration and expiration time

Amplitude Frequency

Van Kaam , BINS 2019

Difference of Conventional Ventilator VS HFOParameter Ventilator

konvensionalHFOV

Rate (frek napas/menit) 0-150 180-900

Volume tidal (mL/kg) 4-20 0,1-3

Tekanan alveol (cmH2O) 0->50 0,1-5

Volume paru pada akhirekspirasi

Rendah Normal

Flow Rendah Tinggi

Primary HFOV for Recruitablelung disesase

Set mean airway pressure (MAP) at 6-8 cmH2O and adjust FiO2 to give an SpO2 90-95% (A)

Increase MAP by 1-2 cmH2O every 2-3 min. Reduce FiO2 stepwise by 0.05-0.10 to maintain SpO2 90-95%

Stop increasing MAP when FiO2 is smaller than 0.3 or when FiO2 is not able to be decreased with an

increase in MAP (B)

Decrease MAP by 1-2 cmH2O everey 2-3 min until SpO2 falls (C)

Recruit the lung again by returning to the known CDP (step 3) for 2-3 min then decrease MAP to 2

cmH2O above the closing pressure (CDPC) from step 4 (D&E)

5-10 min after surfactant, reduce MAP by 1-2 cmH2O every 5 min until SpO2 falls.

Set MAP at 2 cmH2O above post-surfactantclosing pressure (CDPC) identified in step 6.

Increase MAP by 1-2 cmH2O every 5 minuntil SpO2 returns to previous value at end

of step 5.

Pre-surfactant opening continious distandingpressure (CDPO)

Pre-surfactant closing pressure (CDPC)

Pre-surfactant optimal pressure (CDPOPT)

Obtain chest X-ray & give surfactant

Post-surfactant closing pressure (CDPC)

Post-surfactant opening pressure(CDPO)

Post-surfactant optimal continiousdistending pressure (CDPOPT)

1

2

3

4

5

6

7

8

Pillow J, HFO Ventilation 2016

HFOV VS Mechanical Ventilator

Primary Mode

BW < 1500 gram, GA< 32 weeks; Severe RDS

Randomized : 184 HFOV vs 182 SIMV + PS

18 month follow up

SIMV (n=179) HFOV(n=177) p

BPD at 36 weeks 28/166 13/173 0.04

Death 13/179 4/177 0.01

CP 14/143 5/145 0.03

MDI< 70% 45/143 29/145 0.03

Visual impairment 4/143 2/145 0.45

Hearing loss 4/143 3/145 0;72

Sun at al, Resiratory Care, Feb 2014 Vol 59 No 2

Combination HFOV + Continuous Mandatory Ventilation (CMV) ??

Basically it is HFO mode, but periodically ventilator will give CMV (sigh effect)

Lei at al : HFOV plus CMV can improve lung oxygenation and clinical outcome, and reduce the incidence rate of pneumothorax without increasing the risk of intracranial haemorrhagecompared to CMV alone

CMV should be 1-2 times/minute

Lei at al. Journal of clinical medicine in practice.2002;02:178-9

Combinations HFOV and Volume Target Ventilation

HFOV+ VTV or HFOV + VG

Set a TVhf (1.5-2 mL/kg) and Amp Max

Ventilator adjusts amplitude to target and stabilize TVhf

Aim to avoid swings in TVhf more stable PaCO2

Paw

Time

Pressure

Amp

l

Vthf

time

Volume

HFO+VTV : initial setting and adjustment

HFOVPaw = 2 cmH20 +Pmean CMVIT: 33%Frequency 10-12 HzAmplitude 1.5-2 Paw

Observe Vthf dan Working Amp which give PaCO2 35-45 mmHg

HFO+VTVSet VtHFOAmplitude max = 5 + Working Amp

High PCO2

Chest wiggle, DOPES

Vthf target is reached

Working Amp = Amp Max

Increase Amp Max Increase freq

Increased Vthf 0,1-0,2 mL/kg

Reduced MAP if overdistended

Yes No

NoYes

Management Hypercarbia during HFO+ VTV

Management Hypocarbia During HFO+VTV

• Reduce Vthf by 0,1-0,2 cmH2O

• Pay attention to put Vthf always within the range for frequency selected

• If Vthf is in the lower limit of selected frequency increase frequency than reduce Vthfaccordingly

Frequency Lower limit(mL/Kg)

Upper limit(mL/Kg)

5 2,8 3.6

7.5 2,3 2.7

10 2,0 2.5

12.5 1,8 2.3

15 1,6 2.0

HFOV + VTV

Neonatology 2015;108:277–282

Make sure that we have achieved

Improvement of underlying

disease

Adequate spontaneous

breathing

No anemia

Acceptable blood gas result and

pH

Low pain score wean morphin

minimal at 5-10 mcg/kg/min

Better chest X Ray

Weaning

Ventilatory setting at which extubation should be considerd

Conventional Ventilator (PTV)MAP < 7 cmH2O and FiO2 < 30% ,

MAP < 7 cmH2O and FiO2 < 30% ,Conventional Ventilator (PTV+ VTV)BW < 1000 g; MAP < 7 cmH2O and FiO2 < 30% ,

BW > 1000 g; MAP < 8 cmH2O and FiO2 < 30% ,

High Frequency Oscillating VentilatorBW<1000; MAP< 8 cmH20 and FiO2 < 30%BW>1000; MAP< 9 cmH20 and FiO2 < 30%

Prediction of Successful Extubation

Spontaneous Breathing Test3 minutes ET CPAP with PEEP 5-6 cmH20No Persistent bradycardia > 15 secondsNo SpO2 below 85% despite a 15% increase in FIO2

Kamlin O. Arc Dis Child Foet Neo Ed.2008;93:305-6

Extubation

• Spontaneous breathing with lowest effort

• Reduce sedation

• Methylxanthines (caffeine)

• Blood gas should be within acceptable limits.

• Withhold feeding an hour prior to extubation

• Non invasive (CPAP/NIPPV) with comparable MAP is immediately applied prior to extubation

• Prone position

• Abdominal decompression by OGT

Conclusion

1. Lung protective strategies is one way to reduce the incidence of CLD

2. Lung protective strategies should be applied from delivery room to NICU.

3. Optimal gas exchange, patient comfort and means to reduce lung injury should be our aims when we put a baby on ventilator.

Thank You