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Published on: October 11, 2011
Late Permissive Hypercapnia for Mechanically Ventilated Preterm Infants: A Randomized Trial
Colm P Travers1, Samuel J Gentle1, Vivek V Shukla1
1Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Insights
Targeting higher levels of permissive hypercapnia (pH-controlled) in preterm infants after 7-14 days of mechanical ventilation increased ventilator-free days. This approach may offer lung protection compared to lower permissive hypercapnia levels.
Area of Science:
- Neonatalogy
- Pediatric critical care
- Respiratory physiology
Background:
- Permissive hypercapnia is used in mechanical ventilation for preterm infants with respiratory distress syndrome.
- Optimal target levels for permissive hypercapnia beyond the initial postnatal period are not well-established.
- This study investigated higher vs. lower pH-controlled permissive hypercapnia targets.
Purpose of the Study:
- To determine if targeting higher levels of pH-controlled permissive hypercapnia beyond postnatal day 7-14 reduces mechanical ventilation duration in preterm infants.
- To assess the impact of higher permissive hypercapnia levels on ventilator-free days and bronchopulmonary dysplasia.
- To evaluate the potential lung-protective effects of higher permissive hypercapnia targets.
Main Methods:
- Single-center randomized clinical trial (NCT02799875) with 130 preterm infants (22-36 weeks' gestation).
- Infants received either higher (PaCO2 60-75 mmHg, pH ≥ 7.20) or lower (PaCO2 40-55 mmHg, pH ≥ 7.25) pH-controlled permissive hypercapnia for 28 days.
- Primary outcome: days alive and ventilator-free within 28 days post-randomization.
Main Results:
- Infants in the higher permissive hypercapnia group had significantly more alive ventilator-free days (11 ± 10 vs. 6 ± 8; P = 0.009).
- No significant difference in grade 2-3 bronchopulmonary dysplasia or death before discharge between groups (44% vs. 59%; aOR 0.54).
- Grade 2-3 bronchopulmonary dysplasia among survivors at 36 weeks' postmenstrual age did not differ significantly between groups (35% vs. 50%; aOR 0.56).
Conclusions:
- Targeting higher levels of permissive hypercapnia from postnatal day 7-14 increased ventilator-free days in preterm infants.
- This strategy may offer lung protection compared to lower permissive hypercapnia levels.
- Further research is needed to fully elucidate the long-term effects and optimal management strategies.
Objective:
To determine if targeting higher levels of pH-controlled permissive hypercapnia beyond postnatal day 7-14 reduces mechanical ventilation duration in preterm infants.
Methods:
Single-center randomized clinical trial with a 1:1 parallel allocation including infants from 22-36 weeks' gestation mechanically ventilated for respiratory distress syndrome on postnatal day 7-14. We targeted higher levels of pH-controlled permissive hypercapnia (60-75 mmHg and pH ≥ 7.20) or lower levels of pH-controlled permissive hypercapnia (40-55 mmHg and pH ≥ 7.25) for 28 days after randomization. The primary outcome was the number of days alive and ventilator-free in the 28 days after randomization.
Results:
We enrolled 130 infants with a gestational age (mean ± SD) of 24 weeks and 5 days ± 2 weeks and 0 days and birth weight of 657 ± 198 grams from December 2015 to May 2021. Infants randomized to higher levels of pH-controlled permissive hypercapnia had more alive ventilator-free days than infants randomized to lower levels of pH-controlled permissive hypercapnia (11 ± 10 vs. 6 ± 8; p = 0.009). Grade 2-3 bronchopulmonary dysplasia or death before discharge was not significantly lower in the higher carbon dioxide (PCO2) group (30/62 (44%) vs. 45/68 (59%); adjusted odds ratio (aOR) 0.54, 95% confidence intervals (CI) 0.27-1.08; p = 0.08). Grade 2-3 bronchopulmonary dysplasia among survivors at 36 weeks' postmenstrual age did not differ significantly (higher PCO2 19/53 (35%) vs. lower PCO2 28/53 (50%); aOR 0.56, 95% CI 0.27-1.13; p = 0.12).
Conclusions:
Targeting higher levels of permissive hypercapnia from postnatal day 7-14 increased the number of days alive and ventilator-free and may be lung protective compared with targeting lower levels.
Trial Registration:
Clinicaltrials.gov (identifier number NCT02799875). The first infant was enrolled in December 2015 and the trial was not registered until June 2016. The authors confirm that there were no changes made to the Institutional Review Board (IRB) approved trial protocol (dated 10/20/2015) or any amendments made after recruitment started, between the date of first enrollment and the date of clinicaltrials.gov registration, or between study commencement and completion. Furthermore, the authors confirm that the data were not unblinded until after the last infant had been enrolled (March 2021) and discharged from the hospital (August 2021). Study Details | Late Permissive Hypercapnia for Intubated and Ventilated Preterm Infants | ClinicalTrials.gov.
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