The pain experienced by newborns frequently appears during invasive interventions. It has been recently documented that only 1% of infants receive pharmacologic interventions to treat pain during immunisation in clinical practices (
15). Pharmacotherapy is effective in reducing the pain from medical procedures, and promising interventions for immunisation pain include topical local anesthetics (
16,
17).
Physiological symptoms caused by painful stimulators indicate the general stress state of the body. While the most frequently used physiological symptoms, such as heart rate, blood pressure, respiration and oxygen saturation, are used in the evaluation of pain occurring due to acute procedures, hormonal and metabolic variables are used in the assessment of prolonged and chronic pain (
2). Although no statistical difference was observed between the groups in terms of pre-procedural respiration, heart rate, systole, diastole and fever mean scores, a significant difference was found between groups in terms of post-procedure PO
2 and body temperature, which is contrary to the literature (
Table 2). In the study conducted by Ok (
18), the efficacy of EMLA cream in the reduction of pain occurring during intravenous cannulation for premature infants was examined and the highest increase in peak heart rate was seen in newborns in the control group during the procedure. However, the difference between groups was not statistically significant. In other studies, it was stated that respiratory rate, heart rate, blood pressure and oxygen saturation were not significant in pain analysis before and after the procedure (
10,
19).
Routine immunisation is the most common reason for iatrogenic pain in childhood (
20). In the study, it was determined that, according to mean pain scores, the pain of newborns in the control group was severe and the pain of newborns in the intervention and placebo groups was at a medium level (
Table 3). Topical local anaesthetics have been consistently shown to reduce injection pain (by 40%) during the administration of various vaccines, including diphtheria-pertussis-tetanus (
21), diphtheria-pertussis-tetanus and polio (
22), diphtheria-tetanus-acellular pertussis-inactivated poliovirus–
Haemophilus influenzae type b conjugate, hepatitis B27 and measles-mumps-rubella (
23). In the study conducted by Dilil et al. (
17) infants in the lidocaine-prilocaine group cried for a shorter period compared to infants in the control group during vaccination. Taddio et al. (
24) reported a significant increase in the latency of the first cry and a decrease in the duration of the first cry for infants who received lidocaine-prilocaine versus the placebo. In the study conducted by Nahum et al. (
25), the mean PIPP scores were significantly lower in the EMLA group compared with the placebo group during suprapubic aspiration in young ınfants. Similarly, parents reported lower mean pain and crying scores in the lidocaine-prilocaine group in comparison with the placebo group. Instrumental touch was used in this group as all groups of study. However, it was thought not to perceive this shape of the touch by infants because of the effect of the local anesthetic drug.
In the study, it was determined that even though no painful procedure was applied in the placebo group, 25% of the infants felt severe pain (
Table 4). Preterm and term newborns, who have to spend the first week of their lives in NICUs, experience pain and stress due to various reasons. They are exposed to many procedural touches like invasive procedures without analgesia. Much of this touch in the NICU is a procedural touch, and infants born very preterm often miss out on comforting touch stimulation (Smith 2012 (
26)). Morris et al. (2014) (
13) also showed that a large majority of touches were instrumental and pertained to functional mobility. Among these interventions are bloodletting from the heel, venous intervention, arterial catheterisation, lumbar puncture, newborn examination, medical dressing change, gavage tube insertion, IM injection, postural drainage, removing sutures, circumcision, etc. All these painful interventions are also stressful and affect the clinical course of infants. The pain experienced by the infant may affect his/her behaviors, family-infant interaction, and adaptation with the outside world. It may also cause changes in the development of the senses and the brain as well as negatively affect growth. Newborns experience physiological and metabolic problems as well as the above-mentioned behaviors. Among them, the following can be included: excess protein consumption, electrolyte imbalance, sepsis resulting from a weak immune system, metabolic acidosis, pulmonary and cardiac failure and death (
27). Untreated procedural pain in childhood was shown to have significant adverse sequelae, including the development of hypersensitivity to future pain, preprocedural anxiety because of conditioning and needle phobia (
21). From this perspective, it has been shown that health care professionals should use more expressive touch when handling babies.
In supporting the development of infants, reductions in stress symptoms, increases in stability symptoms, regulations in individual care and pain control, care should be provided in NICUs. It is required to evaluate carefully the pain of newborns and to learn treatment interventions. EMLA cream is a useful adjunct to local anesthetic for newborn vaccinations because it effectively reduces the sharp pain induced by needle punctures. In addition, it has been emerged that health care professionals need to do more expressive touch.
5.1. Limitation
Conducting our study in only one city a neonatal intensive care unit is a limitation of this study. Another important limitation is that the study was completed with a low number of preterms.