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Published on: January 29, 2011
Late permissive hypercapnia and respiratory stability among very preterm infants: a pilot randomised trial
Colm P Travers1, Waldemar A Carlo2, Arie Nakhmani3
1Department of Pediatrics, The University of Alabama at Birmingham, Birmingham, Alabama, USA cptravers@uabmc.edu.
Insights
Targeting higher transcutaneous carbon dioxide in very preterm infants did not improve respiratory stability. Achieving the intended carbon dioxide levels proved challenging, indicating potential limitations in this ventilation support strategy.
Area of Science:
- Neonatal Medicine
- Respiratory Physiology
- Critical Care
Background:
- Very preterm infants on ventilatory support often experience respiratory instability.
- Managing transcutaneous carbon dioxide (TcCO2) levels is crucial for optimizing respiratory support.
- Previous strategies for TcCO2 manipulation require further investigation in this vulnerable population.
Purpose of the Study:
- To determine if targeting higher TcCO2 improves respiratory stability in very preterm infants receiving ventilatory support.
- To evaluate the impact of manipulating TcCO2 on cardiorespiratory events and hypoxaemia.
Main Methods:
- A single-centre pilot randomized clinical trial was conducted.
- Very preterm infants (postnatal day >7) on ventilatory support were randomized.
- Interventions involved targeting 5 mmHg changes in TcCO2 over 96 hours using distinct protocols.
Main Results:
- Twenty-five infants were enrolled; no significant difference in mean TcCO2 between groups.
- No significant differences were observed in episodes of intermittent hypoxaemia or bradycardia.
- Proportions of time with low oxygen saturation, cerebral, or abdominal hypoxaemia did not differ between groups.
Conclusions:
- Targeting 5 mmHg changes in TcCO2 did not enhance respiratory stability in very preterm infants.
- Difficulty in achieving and maintaining the intended TcCO2 separation was noted.
- Further research is needed to refine TcCO2 management strategies in this population.
Objective:
Determine if targeting higher transcutaneous carbon dioxide improves respiratory stability among very preterm infants on ventilatory support.
Design:
Single-centre pilot randomised clinical trial.
Setting:
The University of Alabama at Birmingham.
Patients:
Very preterm infants on ventilatory support after postnatal day 7.
Interventions:
Infants were randomised to two different transcutaneous carbon dioxide levels targeting 5 mm Hg (0.67 kPa) changes with four sessions each lasting 24 hours for 96 hours: baseline-increase-baseline-increase or baseline-decrease-baseline-decrease.
Main Outcome Measures:
We collected cardiorespiratory data evaluating episodes of intermittent hypoxaemia (oxygen saturations (SpO2)<85% for ≥10 s), bradycardia (<100 bpm for ≥10 s), and cerebral and abdominal hypoxaemia on near-infrared spectroscopy.
Results:
We enrolled 25 infants with a gestational age of 24 w 6 d±11 d (mean±SD) and birth weight 645±142 g on postnatal day 14±3. Continuous transcutaneous carbon dioxide values (56.8±6.9 in the higher group vs 54.5±7.8 in the lower group; p=0.36) did not differ significantly between groups during the intervention days. There were no differences in intermittent hypoxaemia (126±64 vs 105±61 per 24 hours; p=0.30) or bradycardia (11±16 vs 15±23 per hour; p=0.89) episodes between groups. The proportion of time with SpO2<85%, SpO2<80%, cerebral hypoxaemia or abdominal hypoxaemia did not differ (all p>0.05). There was moderate negative correlation between mean transcutaneous carbon dioxide and bradycardia episodes (r=-0.56; p<0.001).
Conclusion:
Targeting 5 mm Hg (0.67 kPa) changes in transcutaneous carbon dioxide did not improve respiratory stability among very preterm infants on ventilatory support but the intended carbon dioxide separation was difficult to achieve and maintain.
Trial Registration Number:
NCT03333161.
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