Elimination of ventilator dead space during synchronized ventilation in premature infants☆
Section snippets
Endotracheal tube adapter continuous leakage technique
This technique consists of a 15-mm-long, open-ended tube with a resistance of 680 centimeters of water (cmH2O) per liter per second attached to the side port of the ETT adapter, as shown in Figure 1. Leakage flow determined by the positive end-expiratory pressure (PEEP) during mechanical expiratory time (Te) remains nearly constant. A PEEP of 4 cmH2O creates a leakage flow of approximately 0.35 liters per minute to clear a volume of 1.1 mL in 0.2 seconds. Leakage flow increases during
Results
Ten preterm infants were studied without adverse events. Their birth weight was 835±244 g and gestational age was 26±2 weeks. They were 19±9 days old and weighed 856±206 g at study time. Ventilatory support consisted of a mechanical rate of 21±6 breaths per minute, PIP of 16±1 cm H2O, and PEEP of 4.2±0.4 cm H2O and required an Fio2 of 0.26±0.6 to maintain Spo2 >90%. Ti ranged between 0.35 and 0.4 seconds and ventilator bias flow between 8 and 9 L/min. Eight infants were ventilated through a
Discussion
In this group of infants, sensor dead space increased CO2 rebreathing and resulted in a significantly higher alveolar CO2 and Tcpco2 and led to an increase in spontaneous compensatory respiratory effort during both conventional and synchronized ventilation. These effects were effectively prevented by the ETT adapter continuous leakage technique.
The effectiveness of the ETT adapter continuous leakage was increased by rapid clearance of exhaled CO2 at end-expiration, when concentration is
References (18)
- et al.
Improved oxygenation during synchronized intermittent mandatory ventilation in neonates with respiratory distress syndrome: a randomized, crossover study
J Pediatr
(1995) - et al.
Randomized multicenter trial comparing synchronized and conventional intermittent mandatory ventilation in neonates
J Pediatr
(1996) - et al.
The effect of rebreathing CO2 on ventilation and diaphragmatic electromyography in newborn infants
Respir Physiol
(1985) - et al.
Increased and more consistent tidal volumes during synchronized intermittent mandatory ventilation in newborn infants
Am J Respir Crit Care Med
(1994) - et al.
Influence of different methods of synchronized mechanical ventilation on ventilation, gas exchange, patient effort and blood pressure fluctuations in premature neonates
Pediatr Pulmonol
(1996) - et al.
Anatomic dead space in infants and children
J Appl Physiol
(1996) - et al.
Changes in Tcpco2 regarding pulmonary mechanics due to pneumotachometer dead space in ventilated newborns
J Perinat Med
(1997) - et al.
The effect of instrumental dead space on measurement of breathing pattern and pulmonary mechanics in the newborn
Pediatr Pulmonol
(1993) - et al.
What are the mechanisms producing increased ventilation in dead space studies in neonates?
Pediatr Pulmonol
(1990)
Cited by (37)
Patient-Ventilator Interaction
2018, The Newborn Lung: Neonatology Questions and Controversies, Third EditionNeonatal Respiratory Therapy
2018, Avery's Diseases of the Newborn: Tenth EditionDeterminants of pulmonary dead space in ventilated newborn infants
2017, Early Human DevelopmentCitation Excerpt :Furthermore, we aimed to determine whether VD differed between preterm and term infants or between those who subsequently did or did not develop BPD. Such results would be important as they would inform the determination of the optimal targeted tidal volume, as a higher VD would necessitate a higher delivered tidal volume [9]. A retrospective analysis was undertaken of data collected during a study that assessed readiness for extubation using a spontaneous breathing trial (SBT test).
Neonatal Respiratory Therapy
2017, Avery's Diseases of the Newborn, Tenth EditionSpecial Techniques of Respiratory Support
2017, Assisted Ventilation of the Neonate: An Evidence-Based Approach to Newborn Respiratory Care: Sixth EditionStrategies for Limiting the Duration of Mechanical Ventilation
2012, The Newborn Lung: Neonatology Questions and Controversies Expert Consult
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Supported by the University of Miami Project Newborn.
Presented in part at the 2002 Society for Pediatric Research Meeting, Baltimore, Maryland.