Materials and methods
heel bleeding, ’ venous blood, Pain, pain, congenital problems, ’s head circumference
BLOOD, DISEASE, HEART
The present clinical trial study was conducted in 2021 on 148 premature Infants admitted to the Neonatal Intensive Care Units (NICU) of Rouhani and Children’s Hospitals in Babol with the permission of the Ethics Committee of Babol University of Medical Sciences (code IR.MUBABOL.HRI.REC.1398.188) and informed consent. Sampling in the first stage was done as convenience. Then, the infants were assigned to four groups of 37: control, eye shield, ear muffs, and eye shield plus ear muffs based on the random allocation method. With applying the inclusion and exclusion criteria, infants were assigned into groups using the permuted block randomization method. The randomization unit included infants, and the block size was 4. To conceal random allocation, a list generated by a statistician was used. The assigned group of each subject had a specific code that was a combination of numbers and letters with no special order. This list was not provided to the principal of the study (researcher) and the person responsible for the allocation [In this study, inclusion criteria include: premature infants with a gestational age of 28 to 37 weeks, Apgar above 7 in 5 min, no painful procedure at least 6 h before blood sampling, Sampling should be done when the baby is awake and active and in between feedings. Also, the exclusion criteria include premature infants with congenital problems, not using narcotic and antidepressants for the mother during pregnancy and not using analgesic in infants, 12 h before blood sampling. This study was registered in Iran’s clinical trial site with number IRCT20200913048704N1.The sample size were based on the previous study [
Selection of the study participantsInfants’ venous blood sampling were performed following the NICU doctors’ order according to the clinical goals. In each study group, using an eye shield and ear muffs started 15 min before blood collection and continued until 15 min after blood collection in order to investigate its effect on the intensity of blood collection pain [The data collection tool included demographic profile questionnaire and NIPS pain measurement scale. Demographic characteristics included: gestational age, gender, weight, height, infant’s head circumference, hospitalization date, disease diagnosis, and mother’s type of delivery. The researcher completed the first part of the questionnaire before sampling. In this study, pain response was recorded by the researcher’s assistant based on the NIPS scale and the infant’s behavioral and physiological changes (respiratory pattern) by videotaping the infant 15 min before, during, and 15 min after blood sampling. During the video recording, the camera was focused on the infant. In addition, the interpretation of the video was performed by the researcher and her assistant. Blood sampling was performed by a nursing expert in each hospital who had at least one year of experience in the NICU, with a single entry of the needle gauge24-26. In order to simultaneously observe the infant’s face, the video recording was performed by the researcher’s assistant. Heart rate (HR) and its changes (VHR) (measured within 30 s) 15 min before, during, and 15 min after blood sampling, as well as oxygen saturation, were checked using a cardiorespiratory monitoring device.This study evaluated pain in infants using the Neonatal Infant Pain Scale (NIPS). This tool has six items, 5 of which are behavioral (facial movements, crying, movements of hands, legs, and state of consciousness), and one is physiological (breathing pattern). The total score obtained in this tool is between 0 and 7. This tool is used for both groups of full-term and premature infants and is generally used to evaluate pain caused by heel bleeding and venous or arterial puncture and pain after surgery [In this scale, six items are examined:1- Facial expression (zero for a relaxed state and one for a tense and frowning state). 2- Infant crying (zero for no crying, 1 for whining, and 2 for intense crying). 3- Breathing pattern (zero for relaxed state and one for breathing change). 4- Movement of the hands (zero for relaxed state and one for folding or opening). 5- Movement of the legs (zero for relaxed or lying down and one for folding or unfolding). 6- State of consciousness (zero for sleep or wakefulness and one for screaming and shouting). In general, a score of 0–3 indicates no pain, a score of 4–5 indicates moderate pain, and a score of 6–7 indicates severe pain [After collecting the data, it was entered into SPSS software version 23. Chi-Square was used to measure qualitative variables and t-test was used to measure quantitative variables. Using repeated measurement test and analysis of variance (ANOVA), the difference in pain score, HR and VHR and behavioral changes at different times were investigated.