1. The Babylog 8000 plus with Pressure Support and Volume Guarantee
The Key to Breathing Harmony

2. Babylog 8000 plus Comprehensive modes: CPAP, IMV, SIMV, A/C, PSV
A ventilator designed specifically for critically ill newborn infants
Comprehensive modes: CPAP, IMV, SIMV, A/C, PSV
Volutrauma protection strategy: Volume Guarantee option in SIMV, A/C, and PSV modes
Leak- adapted flow synchronization

3. PSV with Differences First the Similarities:
Pressure targeted breath (both spontaneous and set)
Flow terminated at 15% of peak inspiratory flow
Inspiratory time will vary and is patient dependent
Preset Insp. Time still functions as a back-up, breath will not exceed clinician setting

4. PSV with Differences Now the big differences:
A “back-up” rate is set - so yes, in theory a paralyzed patient can be placed on PSV, Babylog style
All breaths, whether patient assisted or not will be pressure targeted and flow terminated
PSV may be combined with the volume guarantee (VG) option – allowing clinicians to set tidal volume

5. Pressure Support Ventilation (PSV) Patient or vent ilator initiated
Set Pinsp
Paw
Peak flow
insp V •
Drop to 15%
of peak flow
Pressure support is a mode used successfully in spontaneously breathing adults and older children. As pressure builds with volume delivery to the lungs, flow tapers off. When flow drops to 15% of peak value, the ventilator ends inspiration. In other words, the ventilator adjusts inspiratory time based on near- zero flow, similar to what we tried to do manually. The ventilator, however, can do it for each breath as it happens.
Patient or vent ilator initiated
inspiration
exp
PSV cycled
expiration

6. Pressure Support Ventilation with leak compensation
Flow termination
automatically compensates
for leak
Onset of
inspiration
expiration
Leak flow
The Babylog pressure support mode compensates for leak flow, keeping the flow criterion to end inspiration intact.

7. Examples courtesy of Prof. JC Rozé, Nantes, France
Patient- Set Inspiratory Time in Neonatal Pressure Support Ventilation (PSV)
Examples courtesy of Prof. JC Rozé, Nantes, France
The average Inspiratory Time of the four patients on PSV above was ~ .25seconds – expect to see shorter I times, and consequently a drop in the MAP

8. Why let the infant end inspiration (set Tinsp ) ?
CBF variability increases IVH risk
Perlman , et al. N Engl J Med 1983
CBF variability and IVH increases with infant- ventilator asynchrony
Perlman , et al. N Engl J Med 1985
Rennie, et al. Arch Dis Child, 1987
So, harmonizing ventilator- infant interaction should reduce IVH.

9. Why give mechanical support for all breaths?
Decreases Work of Breathing
Jarreau, Moriette, Mussat, et al; Am J Resp CCM, Mar 1996
Decreases Oxygen Consumption
Roze, Liet, Gournay, Debillon, Gaultier; Eur Resp J, Nov 1997
Reduced Stress Hormone Levels
Quinn, de Boer, Ansari, Baumer; Arch Dis Child, May 1998
Decreased Effort and Respiratory Rate
Bendel- Stenzel, Bing, Meyers, Connett, Mammel; Ped Res, May 1998
Less Variation in Vt After Surfactant
Mrozek, Bendel- Stenzel, Meyers, Bing,, Mammel; Ped Res, May 1998

10. Problems with a Preset Ti: Patient Asynchrony
The infant attempts to breathe during a set ventilator inspiratory cycle, resulting in lower lung pressure and excessive volume.

11. Volume Guarantee: How does it work?
The VG option allows for delivery of a set volume during mandatory pressure breaths in A/C, SIMV, and PSV
Similar to Autoflow on the Dura, the PIP will adjust automatically up to a set maximum, compensating for changes in resistance and/or compliance, to ensure the set tidal volume is delivered
The inspiratory Pressure knob now functions as the maximum pressure allowed, NOT the set PIP. PIP is not set, and will vary.

12. Problems with Volume Guarantee
Similar to autoflow, high respiratory demand from the patient will result in a lower PIP delivered to the airway, i.e. less support for the patient.
PATIENTS MUST BE CLOSELY MONITORED FOR SIGNS OF INCREASED WOB WHEN UTILIZING THE VOLUME GUARENTEE MODE!

13. Postulated mechanism of action:
Why volume - oriented ventilation ( VOV ) in infants?
VOV vs SIMV: Equivalent ventilation
at lower MAP
Herrera, at al. Ped Res 1999
VOV reduces IVH, acute lung injury
Rosen WC, et al. Ped Pulm 1993
Sinha SK, et al. Arch Dis Child Fetal Neo Ed 1997
Postulated mechanism of action:
Consistent Vt
Stable PaCO2
Stable CBF
Less IVH

14. Why volume - oriented ventilation ( VOV ) in infants?
Pressure ventilation may cause hypoventilation or overdistention when CL changes
Davis, et al. N Engl J Med 1988
Gibson, et al. Eur J Pediatr 1994
Bjorklund, et al. Am J Respir Crit Care Med 1996
Dimitriou, et al. J Perinat Med 1997
Lung overdistention creates acute / chronic lung injury
Herandez, et al. J Appl Physiol 1989
Bjorkland, et al. Ped Res 1997
Variable PaCO2 in pressure ventilation increases IVH
Stewart, et al. Pediatrics 1981

15. Pressure Support Mode with Volume Guarantee : Concept of “Autoweaning”
PIP
C lung Vt
Extubate!
Time
So far I’ve talked about ventilatory support of infants when they are acutely ill with respiratory distress. What about weaning from the ventilator?
Unlike adults, I think that preterm infants don’t become ventilator- dependent as long as our ventilator management can keep up with the infants’ improving lung function. I think using the pressure support mode with VG can make this easy for us.
As lung function improves over time, the ventilator will reduce inflation pressure to maintain the set tidal volume. The infant will control rate and inspiration time throughout. We’ll have a backup rate set in case of central apnea episodes. There comes a point where the pressure won’t change much; as it is primarily overcoming ETT resistance. Then the infant should be extubated. If apnea remains a problem, at least we are delivering the least mechanical force for adequate ventilation. This is theoretical; we need clinical trials to prove it.

16. Tidal volume delivery in mechanically ventilated preterm infants
Appropriate tidal volume for mechanical ventilation of preterm infants with surfactant deficiency is
4 - 6 mL/ kg body weight.

17. A Happy Child
PSV+VG

18. Two Extra Pictures - The Neonatal flow sensor
Hot wire anemometer
Sensitive to 0.17 mL
lpm range
Weighs 10 grams
0.5 mL added deadspace
Inexpensive
6 month use

19. Flow Sensor Measurement Principle
Hot wire anemometer:
Two tiny platinum wires are heated to 400°C
One wire is shaded to determine direction of gas flow
Wire cooling is proportional to gas flow
Flow is integrated with time for volume measurement