The Effect of Swaddling in Physiological Changes and Severity of Pain Caused by Blood Sampling in Preterm Infants: Randomized Clinical Trial

Background: Preterm infants admitted to hospitals are often exposed to many painful interventions, including venous blood sampling. Studies have shown that pain affects neural development and affects the subsequent responses to painful stimuli and behavioural responses. Method: The present study is a randomized controlled clinical trial conducted on 34 preterm infants admitted to the Neonatal Intensive Care Unit of the Persian Gulf Hospital in Bushehr. The infants were randomly assigned into control and swaddling groups using block randomized allocation method. Infants of swaddling group were swaddled by bed sheet 10 minutes before blood sampling until two minutes after it. In both groups, heart rate and arterial blood oxygen saturation were measured and recorded at time intervals of 30 seconds before, during, and 30, 60, 90, and 120 second after blood sampling. From the onset of blood sampling until 2 minutes after it, the infants' faces were videotaped and the videos were observed by a researcher who was not aware of the intervention type and the infants' pain measurement tool (pipp) was completed for 30-second time intervals. Results: The results revealed that pain in the swaddling group was significantly reduced compared to that in the control group. In addition, the results revealed that changes in heart rate were less and more stable and returned to the baseline level faster in the swaddling group, while in the control group, the changes were more and did not return to baseline level even after 120 seconds. Conclusion: based on the results of this study, swaddling can reduce the risk of blood sampling in preterm infants and keep their vital signs in a better status. Thus, it is recommended that nurses to use it as an effective intervention in the neonatal intensive care unit during performing painful procedures such as blood sampling.