Accurate assessment of pain in neonates in the neonatal intensive care unit (NICU) is vital because of the high prevalence of painful experiences, including both daily procedural pain and postoperative pain, in this population. It has been reported that newborns born between the gestational ages (GY) 25-42 and hospitalized in the NICU undergo an average of 14 painful procedures per day in the first 2 weeks of life. The aim of this study is determinin the effect of different procedures on the pain levels of newborns in the Neonatal Intensive Care Unit (NICU).

Accurate assessment of pain in neonates in the neonatal intensive care unit (NICU) is vital because of the high prevalence of painful experiences, including both daily procedural pain and postoperative pain, in this population. Exposure of these infants to many mandatory invasive procedures and poor pain management during this time may lead to different results in the short and long term. Every painful application in newborns causes behavioral and physiological instability. Repeated exposure to painful stimuli produces long-term changes in stress-sensitive brain systems such as the hypothalamic-adrenal system and the developing brain. Therefore, evaluation and prevention of pain in newborns is essential. In the NICU, many medical interventions are often performed on infants that are repetitive, painful, but diagnostically necessary. All environmental stress factors can cause physiological changes such as increased pulse, blood pressure, respiratory rate and a decrease in oxygen saturation in newborns. Increasing energy expenditure to overcome these changes may affect physiological functioning, slowing recovery and adversely affecting the organization of the central nervous system (CNS). Heel blood (TC), vascular access (DY), naso and orogastric (NG-OG) catheter insertion, arterial blood collection, tracheal intubation (TE), various rectal procedures, removal of adhesive tapes, umbilical catheter (UK) insertion and removal, Various procedures such as aspiration, chest physiotherapy applications, diaper changing, various hand contacts, and general body care may induce pain responses in newborns. While these responses are associated with low cognitive and motor scores in early childhood, they may result in changes in visual-perceptual ability and somatosensory sensitivity later on. There are many studies in the literature to increase and prove the accuracy of pain assessment tools. However, since the pain treatments used in these studies were also varied, the homogeneity of the evaluations was insufficient. Therefore, more systematic evaluation studies should be conducted on how to improve pain management in NICUs. Finding which of the painful stimuli affects infants more will also guide the use of treatment methods. The aim of this study is to investigate the effects of different procedures applied in the NICU on the pain levels of term and preterm infants.

Inclusion Criteria:

• Preterm and term infants admitted to the NICU for the first time for various reasons with a hospital stay ranging from 1 to 8 days
• Preterm and term infants who were cared for in an incubator without any pharmacological or non-pharmacological analgesic therapy, muscle relaxant, and sedation treatment in the last 24 hours before the procedure.

Exclusion Criteria:

• Exposed to painful procedures more than 3 times in the same day
• Infants who diagnosed with osteomyelitis, sepsis, pyejonic arthritis, congenital anomaly (Spina bifida, arthrogryposis multiplex congenita)
• Infants with any known neurological diagnosis (Abnormal MRI finding, hydrocephalus, Chiari malformation, asphyxia, periventricular leukomolacia (PVL), acute bilirubin encephalopathy, hypoxic ischemic encephalopathy (HIE))
• Infants who had any surgery

The study included 196 newborns who were hospitalized in SANKO University Hospital Level 3 NICU and exposed to different painful procedures during routine clinical practices under Neonatologist follow-up.