Heart Rate Variability as a Feeding Intervention Outcome Measure in the Preterm Infant

Abstract

Background Feeding interventions for preterm infants aim to reduce the physiologic stress of feeding to promote growth. Heart rate variability (HRV) is a potential non-invasive measure of physiologic stress that may be useful for evaluating efficacy of feeding interventions. Purpose To evaluate whether HRV is a sensitive measure of physiologic stress compared to standard physiologic outcomes in the context of a feeding intervention study. Methods This was secondary analysis of a within-subjects, cross-over design study comparing usual care feeding to a gentle, co-regulated feeding approach (CoReg) in 14 infants born < 35 weeks post-menstrual age. HRV indices were calculated from electrocardiogram data and compared to standard physiologic outcomes, including oxygen saturation (SpO2), respiratory rate (RR), apnea, heart rate (HR), and bradycardia. Data were analyzed using linear mixed modeling. Results Infants fed using the CoReg approach had fewer apneic events and higher RR, suggesting they were able to breathe more during feeding. No statistically significant differences were found in SpO2, HR, bradycardia, or high frequency power (the most commonly-reported measure of HRV). Infants fed using the usual care approach had significantly higher SD12, a measure of HRV indicating randomness in the HR, which is a potential indicator of elevated stress. Implications for Practice SD12 was more sensitive to stress than SpO2, HR, and bradycardia. The utility of HRV as a measure of feeding outcomes in clinical practice needs further exploration. Implications for Research Further exploration of HRV as an intervention outcome measure is needed, particularly evaluating non-linear indices, such as SD12.

Methods for analyzing infant heart rate variability: A preliminary study

“…Table 3 displays HRV indices between ECG and RRi files, which are consistent with other reports of infant HRV in the first month of life (Bartels et al, 2017;Longin et al, 2005;Pados et al, 2017;Patural et al, 2008). However, the current study shows the RMSSD measure to be more sensitive to variations in methodology, namely file type.…”

“…The LF ranges in these studies differ by 0.05 Hz, and the studies use a similar upper limit of 1.5 Hz for HF. Most groups extend the HF band to 1.33 Hz (Pados et al, 2017) or 1.5 Hz (Bartels et al, 2017; Javorka et al, 2017; Kozar et al, 2018) to account for increased infant respiratory rate. The HF upper limit is over three times larger than the HF upper limit seen for adults.…”

Cue-based feeding and short-term health outcomes of premature infants in newborn intensive care units: a non-randomized trial

“…In congruence with these findings, Pados et al using a co-regulatory feeding support approach that focused on reduction of environmental stimuli in the NICU, also found that the number of apnea events decreased during feeding, and the approach supported infants to breathe better during feedings. Unlike this current study, however, oxygen desaturation events failed to differ between the control and intervention groups [27]. On average, preterm infants in the behavioral-cue-based feeding group in this study acquired oral feeding skills 3 days earlier than the control group, and although this difference was not statistically significant, it had clinical and economic significance.…”

Cue-Based Feeding and Short-Term Health Outcomes of Premature Infants in Newborn Intensive Care Units(NICU) : A None-Randomized Trial

“…In congruence with these ndings, Britt et al using a coregulatory feeding support approach that focused on reduction of environmental stimuli in the NICU, also found that the number of apnea events decreased during feeding, and the approach supported infants to breathe better during feedings. Unlike this current study, however, oxygen desaturation events failed to differ between the control and intervention groups [32].On average, preterm infants in the behavioral-cuebased feeding group in this study acquired oral feeding skills three days earlier than the control group, and although this difference was not statistically signi cant, it had clinical and economic signi cance.…”