Page 149 - Physiological based CPAP for preterm infants at birth Tessa Martherus
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There were also concerns that during CPAP support, air escapes into the intestinal tract and causes gastro-intestinal distention (“CPAP belly”) or spontaneous intestinal perforations. However, we did not observe this in the animal studies (Chapter 3) nor did we find spontaneous intestinal perforations in our clinical study (Chapter 5).
The feasibility of physiological based CPAP in clinical setting
We tested the feasibility of our current PB-CPAP approach in a small clinical trial (Chapter 5),
wherein we examined protocol adherence and performed post-trial evaluations with neonatologists. Overall, protocol adherence was good, taking into account that a dedicated
researcher was present who focussed on the algorithm. There were a few minor protocol
deviations in both the PB-CPAP and 5-8 cmH2O CPAP group. In the post-trial evaluation
caregivers indicated that they support the concept of PB-CPAP, but few felt comfortable in
performing our current protocol due to its complexity with many predefined actions and
evaluation moments. Caregivers found that following the protocol was hard to combine with
routine care. While more regular use of PB-CPAP will likely increase the dexterity and
confidence among caregivers, the approach requires simplification before the efficacy of P PB-CPAP will be tested in a larger trial. Although it has become clear in this thesis that the
timing of the CPAP level reduction is essential, the most pragmatic option for simplifying the approach would be to use a consistent CPAP level until the infant is stable and breathing. CPAP can then be decreased when the infant is transferred to the NICU.
Limitations
The main limitation of this study was the use of additional interventions that were used
stimulate spontaneous breathing. These include, tactile stimulation, caffeine, FiO2, which
likely influenced the outcome parameters used in this thesis. In animal experiments (Chapter
3, 4) these were needed to continue the experiment, whereas in the clinical trial (Chapter 5) GD these interventions were given as part of the standard DR care. These interventions improve oxygenation and breathing effort (11-14) and by using these interventions, we may have
introduced bias and have sacrificed our capacity to detect differences in oxygenation and spontaneous breathing. Because the physiological increase in lung aeration is not dependent on oxygenation and breathing effort (despite some breathing being essential), we were still able to demonstrate the evident effect of PB-CPAP on lung aeration.
Our preclinical studies (Chapter 3, 4) provided the scientific basis of PB-CPAP and as the approach was feasible in our animal studies, we assumed that this approach would also be feasible to use in the DR. The approach however, appeared too complex for the clinical setting and a more pragmatic protocol is needed (Chapter 5). In the experimental setting, everything was controlled and the focus of the study was centred on determining the effect of CPAP. However, in the DR the study intervention was secondary to the infants well-being and is only a part of the total delivery room care. Although the small number of inclusions limits us to draw hard conclusions, the observed effect looks promising and the study (Chapter 5),
General discussion
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