Ventilatory Strategies in the Prevention and Management of Bronchopulmonary Dysplasia
Section snippets
Targeting a Higher PaCO2 (Permissive Hypercapnia)
Retrospective studies by Kraybill and coworkers8 and Garland and coworkers9 initially suggested that hypocapnia soon after birth was an independent risk factor for BPD. Subsequently, a prospective randomized trial showed that ventilatory strategies that maintained mild hypercapnia (PaCO2 45-55 mm Hg) were safe and reduced the need for assisted ventilation in the first 96 hours after randomization.10 A larger, multicenter, randomized trial reported that “minimal ventilation” (target PaCO2 > 52
Lower Pressures, Faster Rates, Shorter Inspiratory Times (Ti)
For a given minute ventilation, a faster ventilator rate with a lower tidal volume (TV) is preferred to a slower ventilator rate with a larger TV to reduce volutrauma that is more likely with larger TV. At very rapid ventilator rates, minute ventilation plateaus and later falls21 if the Ti decreases below 3 to 5 time constants and TV delivery is impaired. However, infants with RDS generally have short time constants and thus rapid (>60/min) ventilatory rates are acceptable as both inspiratory
Prophylactic CPAP
Prophylactic CPAP refers to the administration of CPAP soon after birth regardless of the respiratory status of the infant. A recent meta-analysis found no evidence that prophylactic nasal CPAP in infants <32 weeks gestation and/or <1500 g at birth was effective in reduction of BPD, and found there were trends toward an increased incidence of IVH in the infants who received prophylactic CPAP.37 Therefore, prophylactic nasal CPAP is not recommended currently in larger infants. In more immature
Defining What Is Meant by “BPD”
The incidence of BPD has varied from center to center not only due to variations in patient population, disease severity, and characteristics of care, but also because the definition of BPD as “oxygen requirement at 36 corrected weeks’ of age” is often not clear. Physicians may use varying criteria for defining “oxygen requirement.” Walsh and coworkers recently reported on the use of a physiologic definition of BPD in which the definition of BPD was standardized between sites by using a timed
Management of Established BPD
The transition from RDS to BPD is gradual, as the effects of chronic injury and inhibition of alveolar and vascular development overlap with and gradually replace the effects of surfactant deficiency and acute lung injury. As in RDS, the major goal of mechanical ventilation should be to maintain adequate gas exchange while minimizing ventilator-associated lung injury. There are extremely limited data from clinical trials on which to base optimal ventilatory management in established BPD, and
Summary of Overall Strategy to Minimize BPD
Strategies to reduce BPD should involve optimal obstetric care including antenatal steroids, delivery room care to avoid over-aggressive ventilation during resuscitation, and postnatal care with early therapeutic CPAP and avoidance of mechanical ventilation whenever possible. Surfactant may be administered prophylactically in the most immature infants or early in more mature infants with RDS. Larger preterm infants (>1 kg) may be extubated to NCPAP or SNIPPV promptly after surfactant
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Cited by (74)
“Current concepts in assisted mechanical ventilation in the neonate” - Part 2: Understanding various modes of mechanical ventilation and recommendations for individualized disease-based approach in neonates
2020, International Journal of Pediatrics and Adolescent MedicineCitation Excerpt :More controlled studies are warranted before this technique can be applied in routine clinical practice. The most common lung conditions that present with respiratory distress are discussed below with different types of assisted ventilation modes and ventilatory settings [23–28]. Surfactant and respiratory support (if needed) are the main components of treatment for RDS.
Pathophysiology of Ventilator-Dependent Infants
2017, Fetal and Neonatal Physiology, 2-Volume SetFrench Neonatal Society issues recommendations on preventing nasal injuries in preterm newborn infants during non-invasive respiratory support
2023, Acta Paediatrica, International Journal of PaediatricsApplication of neurally adjusted ventilatory assist in the weaning from prolonged mechanical ventilation in pediatrics
2022, Chinese Journal of Applied Clinical PediatricsWide Variation in Unplanned Extubation Rates Related to Differences in Operational Definitions
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