Resident The Children's Hospital of Philadelphia Philadelphia, Pennsylvania, United States
Background: Non-invasive respiratory support is delivered to preterm infants for prolonged periods of time with nasal continuous positive airway pressure (nCPAP) or high-flow nasal cannula (HFNC). Attempts at oral feeds are often restricted on these supports. However, the safety of oral feeding while on nCPAP or HFNC is not well studied.
Objective: To assess for changes in non-nutritive sucking parameters in relation to changes in the level of non-invasive respiratory support, delivered with either nCPAP or HFNC, in preterm infants.
Design/Methods: This is a prospective, randomized, crossover study of 133 preterm infants (Table). Using an instrumented pacifier, non-nutritive sucking parameters were measured during 4 time intervals: R0, R1, R2, and R3 (Figure 1). Baseline parameters were measured during R0. Sucking patterns were compared to paired baseline values for each change in respiratory support during R1, R2, and R3. Changes in parameters were compared in relation to respiratory support type, GA, CGA, and BW. Statistical analysis was performed using Wilcoxon Ranked-Sum, Signed-Rank, and Kruskal-Wallis tests when appropriate.
Results: At R0, neither the type of respiratory support (HFNC vs. nCPAP) nor the level of respiratory support (2 - 5 L/min or 5 vs.6 cmH20, respectively) significantly affected sucking parameters. At R0, infants with CGA 37 weeks (CGA3) at time of study procedure had increased DP Max and Sucks/S compared to infants with CGA 34-37 weeks (CGA2) and infants with CGA <34 weeks (CGA1) at time of study. For infants with CGA weeks at the time of the study, DP Max decreased and Sucks/S increased from R0 to R3 irrespective of whether respiratory support levels were increased (p = 0.013; p < 0.001) or decreased (p < 0.001; p = 0.025) (Figure 2). There were no significant changes in any of the sucking parameters when compared to either increased or decreased respiratory support levels, respectively (Figure 3). Conclusion(s): Changes in non-invasive respiratory support within study parameters did not affect non-nutritive sucking patterns in preterm infants. The changes to DP Max and Sucks/S related to CGA at the time of study procedure are likely to be related to the duration of procedure, since they are independent of respiratory support level or change. Our results provide useful safety information for future studies investigating oral feeding for preterm infants receiving non-invasive respiratory support.
Table 1: Patient Characteristics.
Figure 1: Study Design and Infant Sucking Parameters.
Figure 2: Change in sucking parameters (DP Max and Sucks / Second) over time by corrected gestation age (CGA). CGA1 represents infants <34 weeks CGA at time of study. CGA 2 represents infants 34-37 weeks CGA at time of study. CGA3 represents infants >37 weeks CGA at time of study. CGA1 and CGA2 demonstrated statistically significant decrease in DP Max (P < 0.05) and increase in Sucks / Second (P < 0.05) between measurement periods R0 and R3.
Figure 3: Effect of change in respiratory support on sucking parameters (DP Max and Sucks / Second). There were no statistically significant changes in either DP Max or Sucks / Second when either increasing or decreasing respiratory support for all infants.
Authors/Institutions: David M. Rub, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States; Sagori Mukhopadhyay, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States; Nicolas A. Bamat, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States; Emily C. Woodford, Pennsylvania Hospital, Philadelphia, Pennsylvania, United States; Eric Eichenwald, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States; Soraya Abbasi, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States