PhD student University of Sherbrooke University of Sherbrooke Sherbrooke, Quebec, Canada
Background: One crucial milestone in infants born preterm is the attainment of full oral feeding. Nasal respiratory support (NRS), such as nasal continuous positive airway pressure (nCPAP) and high-flow nasal cannula (HF), is routinely used in convalescing preterm infants. A number of NICU teams fear that nCPAP or HF might disturb the immature protective lower airway reflexes, and result in lung aspiration of milk. We have shown in preterm lambs (Samson N, 2017b) without respiratory impairment that bottle-feeding is safe under nCPAP or HF. These results must be confirmed in the presence of mild to moderate respiratory difficulties, to better mimic clinical conditions where bottle-feeding with nasal respiratory support is considered.
Objective: We aimed at evaluating the safety of bottle feeding in preterm lambs under various NRS conditions with and without respiratory impairment. Our secondary objective was to investigate the effect of NRS on the efficiency of bottle feeding and on sucking-swallowing-breathing coordination.
Design/Methods: 15 lambs born 14 days before full-term (corresponding to ~ 34 weeks gestational age) were surgically instrumented to record sucking, swallowing and respiration, as well as ECG and pulse oximetry. The lambs were bottle-fed during four randomly ordered conditions: nCPAP 6 cmH2O, HF 7 L/min, HFCPAP [HF with a tracheal pressure of 6 cmH2O, to test for the specific effect of positive airway pressure], and no NRS (control). The recordings were performed with and without a 50 % increase in baseline respiratory rate induced by a standardized chest compression (blood pressure cuff). Statistical analyses used a generalized linear mixed model.
Results: Tables 1 and 2 illustrate a few statistically significant differences, with no sign however of impaired safety or efficiency, without or with tachypnea. Similar results are observed for swallowing-breathing coordination. Conclusion(s): None of the 3 tested nasal respiratory support impacted the safety of bottle feeding in preterm lambs, including in the presence of tachypnea. In addition, no clinically-relevant alteration in bottle feeding efficiency or sucking-swallowing-breathing coordination was observed in any condition. Analyses of videofluoroscopy swallow study are ongoing in the same preterm lambs, as well as the effect of sex and maturation.
Financial support: Canadian Institutes of Health Research
Authors/Institutions: Basma Elsedawi, University of Sherbrooke, Sherbrooke, Quebec, Canada; Nathalie Samson, University of Sherbrooke, Sherbrooke, Quebec, Canada; Charlène Nadeau, University of Sherbrooke, Sherbrooke, Quebec, Canada; Charles Alain, University of Sherbrooke, Sherbrooke, Quebec, Canada; Kristien Vanhaverbeke, University of Antwerp, Antwerp, , Belgium; Nam Nguyen, University of Sherbrooke, Sherbrooke, Quebec, Canada; Marie-Ève Poisson, University of Sherbrooke, Sherbrooke, Quebec, Canada; Jean-Paul Praud, University of Sherbrooke, Sherbrooke, Quebec, Canada
