BACKGROUND AND OBJECTIVE: Noise is the most common environmental stressor source for premature infants admitted to the neonatal intensive care unit. Venous sampling is one of the most painful-causing actions in newborns. The aim of this study was to determine the effect of voice loss using ear protector on pain caused by intravenous sampling and heart rate of premature infants.
METHODS: This randomized clinical trial study was performed on 112 premature infants aged between 36 and 28 weeks who were randomly divided into two groups of intervention (56 subjects) and control (n=56). The ear protector was used for the intervention group when the baby was subjected to intravenous sampling. Neonatal pain was measured by PIPP instrument (premature infant pain measuring instrument) in five steps (2 minutes before the needle penetration), (moment of needle penetration), (pump time), (moment of needle withdrawal) and (5 minutes after needle withdrawal). Heart rate was measured with a pulse oximeter (8 times every 30 minutes during 4 hours after using the ear protector) and compared. (IRCT: 2015210828925N1).
FINDINGS: The mean changes in PIPP score were in the intervention and control groups (1.6±5.6 and 4.6±1.6), second (12.1±3.3, and 12.6±2.8), third (13.5±2.7 and 13.4±2.9), fourth (6.4±2.6 and 8.5±2.8), and fifth (5.1±4.2) and 1.6±6.2) respectively. Scores in all states except for the second and third stages were statistically significant in both groups (p<0.05). In addition, the mean of heart rate in the fifth stage in the intervention group (145.8 ± 16.6) was significantly higher than the control group (138.1±21.1) (p=0.03).
CONCLUSION: The results of the study showed that the ear protector used for premature infants is effective in reducing pain during venipuncture.