Ask an answerable question (PICO)：
The neonatal intensive care unit can provide high quality of care for premature infants, but it’s different from the uterine environment definitely. Those surviving preterm infants face complications due to their immature physiological systems and sequelae after necessary medical treatment. Based on the ideal of neonatal individualized development care and assessment program, whether the premature infants can effectively stabilize the vital signs when they’re under necessary medical treatment with non-invasive methods imitating intrauterine environment, the author explores the related question that explored maternal voice on slowed heart rate in premature infants undergoing heel lance procedure.
The Method and Analysis of Literature Review：
After first identifying the question, the framework of PICO is established, the research population (P) is premature infants, intervention measure (I) is maternal voices, comparison measures (C) are routine care, and the outcome(O) is heart rate. Literature search used Cochrane, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed and other databases for relevant articles that were published before December 2020, search strategy Boolean logic "OR" and " "AND" permutation and combination, supplemented by manual retrieval of references and related documents for each article, finally obtained 78 documents from the initial search in the database. After review, 2 of them were finally included in the analysis.
Critical Appraisal：
The Tools for Assessing Quality and Risk of Bias was used to appraise the quality of the reviewed studies for assessing article research bias, and the validity, reliability and applicability of each article individually.
Clinical Application of Evidence：
An experimental study design was conducted in the neonatal intensive care unit and observation infant ward of a medical center in the northern Taiwan after the approval of the research ethics committee. A total of 64 cases were admitted. The experimental group explored maternal voice 3 minutes before heel lance procedure and continued for 13 minutes until the end of the blood collection. The heart rate of premature infants was recorded 3 minutes before the heel lance procedure, at the time of the heel lance procedure, and 1, 10 minutes after blood collection.
Evaluation of Effectiveness：
The generalized estimating equation analysis results of the between-group effects of the adopted intervention on heart rate between the two groups, he infants in the experimental group had significantly lower heart rates than those in the control group at 1 minute after the procedure, and β value was negative. This means that during the heel puncture process of premature infants, the experimental group with a mother's voice can stabilize the heart rate faster than the control group without the mother's voice 1 minute after heel puncture procedure, reaching a statistical difference.
Conclusions and Recommendations：
According to statistics, 1 minute after heel puncture procedure, the mother's voice can effectively stabilize the heart rate of premature infants. Therefore, exploring mother's voice is such a multiple care model, which is a non-invasive and non-pharmatical measure. In the early stage of premature infants, it provides abundant sensory stimulation, and can effectively stabilize the changes in vital signs caused by necessary medical treatment, and maintain the integration of the growth and development of premature infants in the neonatal intensive care unit to facilitate their stable growth.
