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Published on: January 29, 2011
A Moving Target: Studying the Effect of Continuous Transcutaneous CO2 Monitoring in ELBW Infants During an Equipoise
Liron Borenstein-Levin1,2, Noa Avishay2, Ori Hochwald1,2
1Department of Neonatology, Rambam Health Care Campus, Haifa 3525408, Israel.
Insights
Continuous non-invasive monitoring of transcutaneous pCO2 (TCpCO2) in extremely low birth weight infants did not significantly reduce rates of intraventricular hemorrhage or periventricular leukomalacia. Challenges in study design impacted definitive conclusions on TCpCO2 benefits.
Area of Science:
- Neonatal Medicine
- Pediatric Critical Care
- Respiratory Physiology
Background:
- Extremely low birth weight (ELBW) infants are at high risk for neurological complications.
- Continuous monitoring of partial pressure of carbon dioxide (pCO2) may help manage these vulnerable infants.
- Transcutaneous pCO2 (TCpCO2) monitoring offers a non-invasive method for assessing pCO2 levels.
Purpose of the Study:
- To evaluate if continuous TCpCO2 monitoring in ELBW infants reduces high-grade intraventricular hemorrhage (IVH) or periventricular leukomalacia (PVL).
- To assess the impact of TCpCO2 monitoring on the combined outcome of IVH/PVL and death.
- To explore the feasibility of a prospective controlled trial in a rapidly evolving field.
Main Methods:
- Prospective, observational, multicenter study design.
- ELBW infants allocated to a study group (TCpCO2 monitored) or control group based on monitor availability.
- Comparison of IVH/PVL rates and combined IVH/PVL and death outcomes between groups.
Main Results:
- 132 ELBW infants participated; 106 in the study group and 26 in the control group.
- No significant difference in IVH/PVL rates between TCpCO2 monitored and control groups (10% vs. 4%, p=0.7).
- No significant difference in the combined outcome of IVH/PVL and death (16% vs. 15%, p=1.0).
Conclusions:
- Conducting controlled trials in rapidly advancing neonatal care presents significant challenges.
- Monitor availability shifts influenced study group sizes and potentially equipoise.
- The small control group limited definitive conclusions, but highlighted the potential of TCpCO2 monitoring.
Abstract:
Objectives: To assess whether continuous non-invasive pCO2 monitoring by transcutaneous pCO2 monitor (TCpCO2) among extremely low birth weight (ELBW) premature infants, during the first week of life, will decrease the rate of high-grade intraventricular hemorrhage (IVH) or periventricular leukomalacia (PVL) or the combined outcome of IVH/PVL and death. Methods: This was a prospective, observational, multicenter study. Due to ethical constraints, allocation was based on TCpCO2 monitor availability. ELBW infants were either monitored by TCpCO2 monitor (Sentec, Therwil, Switzerland) (study group), or recruited to the control group if a TCpCO2 monitor was not available. Results: A total of 132 ELBW infants participated in the study. The size of the study group (106 infants) and the control group (26 infants) differed because monitor availability increased during the study period reflecting change in standard of care. The groups had comparable gestational age and baseline characteristics. No difference was found in the rate of IVH/PVL in the study vs. control groups (10% vs. 4%; p = 0.7, respectively), or in the combined outcome of PVL/IVH and death (16% vs. 15%; p = 1.0, respectively). Conclusions: This study demonstrates the challenges in conducting a prospective controlled trial in a rapidly evolving medical field. While the study began with a clear equipoise, this balance shifted as the care team gained more experience with TCpCO2 monitoring among the study population, despite the absence of new clinical evidence to justify such a shift. Consequently, the small control group limited our ability to draw definitive conclusions regarding the study's objective. However, our findings may increase awareness of continuous non-invasive pCO2 monitoring in extremely premature infants.
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