Effects of Combined Use of Mother's Breast Milk, Heartbeat Sounds, and Non-Nutritive Sucking on Preterm Infants' Behavioral Stress During Venipuncture: A Randomized Controlled Trial

Abstract

Purpose: Even routine procedures can cause pain and stress, and can be harmful to the fast-growing brain of preterm infants. Mitigating pain and stress with sucrose and analgesics has side effects; thus, an alternate choice is the use of natural breast milk and infants' sensory capabilities. Therefore, this study examined the effects of different integrations of sensory experiences-mother's breast milk odor and taste (BM-OT), heartbeat sounds (HBs), and non-nutritive sucking (NNS)-on preterm infant's behavioral stress during venipuncture.

Design: This study was a prospective, randomized controlled trial.

Methods: Infants born preterm (<37 weeks' gestational age) were enrolled in the study through convenience sampling, and randomly assigned to the following conditions: (condition 1) routine care (n = 36); (condition 2) BM-OT (n = 33); (condition 3) BM-OT + HBs (n = 33); or (condition 4) BM-OT + HBs + NNS (n = 36). Crying duration from puncture to recovery period was recorded using a voice recorder. Facial actions and body movements were measured using an infant behavioral coding scheme and transformed into frequencies during seven stages: baseline (stage 0), disinfecting (stage 1), venipuncture (stage 2), and the recovery period for 10 minutes (stages 3-6).

Findings: Data were analyzed for 138 preterm infants. The corresponding median times to stop crying for conditions 1, 2, 3, and 4 were 137, 79, 81, and 39 s, respectively; the instantaneous occurrence rates of stopping crying for conditions 2, 3, and 4 were 1.469, 1.574, and 2.996 times greater than for condition 1, respectively. Infants receiving conditions 3 and 4 had significantly fewer occurrences of facial actions (stage 6 and stages 4-6, respectively) and body movements (stages 3-6 for both); however, there were no significant reductions in stress behaviors for condition 2 (BM-OT).

Conclusions: The combination of BM-OT, HBs, and NNS could be provided to preterm infants as interventions to prevent and reduce behavioral stress, and facilitate pain recovery during venipuncture procedures.

Clinical relevance: Clinicians should be educated about how to recognize preterm infants' behavioral stress, and to incorporate different sensory combinations of respective mothers' BM, HBs, and NNS into painful procedures to help preterm infants recover from distress.

Keywords: Management of procedural pain; preterm infants; sensory intervention; stress; venipuncture.