Pain evaluation in newborns using the Neonatal Facial Activity Coding scale during blood gases analysis *

BACKGROUND AND OBJECTIVES: This study aimed at evaluating pain of newborns submitted to blood gases analysis by means of the Neonatal Facial Activity Coding scale, as well as at comparing newborns’ physiological parameters before and during arterial puncture. METHODS: This was an exploratory, descriptive and cross-sectional study with 26 newborns submitted to blood gases analysis and admitted to a Neonatal Intensive Care Unit. Data were collected in April and May 2010, by means of an identification form and physiological changes presented by newborns before and during the procedure. RESULTS: There have been newborn facial manifestations of pain (100%), heart rate changes (50%) and decreased oxygen saturation (34.7%). CONCLUSION: When physiological parameters were compared before and during arterial puncture, there have been pain facial manifestations in all newborns as well as physiological changes such as decreased oxygen saturation levels and increased heart rate, according to the Neonatal Facial Activity Coding scale, showing that, although unable to verbalize, newborns are able to show changes expressing the pain felt at arterial puncture. The application of this scale was especially important for favoring sensitization and a holistic nursing care for painful newborns.


INTRODUCTION
Child birth is an important event, with major repercussions in the family environment.Experts 1,2 say that parents, especially mothers, suffer the burden of separation when unable to be close to their healthy baby, due to prematurity, hemodynamic instability or malformations, which are factors which may lead to newborn (NB) admission to the Neonatal Intensive Care Unit (NICU) 1,2 .When admitted to the NICU, NB are constantly handled.It is estimated that they receive approximately 134 painful procedures during their first two weeks of life, or up to 14 painful procedures per day 3 .
ORIGINAL ARTICLE DOI 10.5935/1806-0013.20150035Pain evaluation in newborns using the Neonatal Facial Activity Coding scale during blood gases analysis Rev Dor.São Paulo, 2015 jul-sep; 16(3):176-80 Among several painful procedures performed during NB stay in the NICU there are tracheal intubation, airway aspiration, orogastric probe, removal of adhesives, chest drainage, achievement of central lines, lumbar puncture, venous and arterial punctures 4 .Blood gases analysis is a painful procedure, characterized as an invasive, critical and routine exam in neonatal units, performed in NB with respiratory disorders.Such exam provides values to analyze blood gases and body acid-base balance and is performed via arterial puncture 5 .
For a long time, NB pain was not considered reason for concern by clinical professionals and researchers, because it was believed that they were unable to feel pain.Currently, however, researchers have documented that NB have all functional and neurochemical components needed for pain reception and transmission 6 .
For such, scales were developed to allow NB measurement and identification of pain as the fifth vital sign.Among different pain scales, most widely studied are Neonatal Facial Activity Coding Scale (NFCS), Pain Evaluation Scale (NIPS) and Premature Infant Pain Profile (PIPP) 7 .
Pain evaluation should provide accurate data to determine actions to be taken to prevent, relieve or abolish pain and, at the same time, to evaluate the efficacy of such actions 8 .In light of this set of ideas, there are questions such: which are NB responses to blood gases analysis, by means of the NFCS scale?Are there changes in NB oxygen saturation levels (SatO 2 ) and heart rate (HR) during blood gases analysis?
The study is justified because the proposal is to identify facial manifestations and physiological changes during blood gases analysis, using a scale as measurement tool to characterize NB pain, thus proposing to be a facilitator tool for NICU nurses, to recognize NB pain manifestations during blood gases analysis.In addition to favoring qualification and sensitization of professionals so that they are qualified to evaluate and handle pain of NB admitted to the NICU.The objectives were to evaluate responses of newborns submitted to blood gases analysis by means of the NFCS scale, as well as to compare NB physiological parameters before and during arterial puncture.

METHODS
This was an exploratory, descriptive and cross-sectional study carried out in the NICU of a teaching hospital of the State public network, reference in highly complex obstetric and neonatal assistance.Participated in the study 26 NB admitted to the NICU, who met inclusion criteria of the study: having up to 28 days of life; being admitted to the NICU, being monitored with pulse oximetry and with indication for blood gases analysis.Data were collected in April and May 2010, by means of the NFCS scale and with the help of NB identification form, as well as the presence of sedation, oxygen therapy support, number of arterial puncture attempts and SatO 2 and HR responses before and during procedure.
NFCS scale evaluates the presence or absence of pain as from eight facial movements: brow bulge, stretched mouth (horizontal/vertical), eyelids squeezed shut, taut tongue, deepening of naso-labial fold, tongue protrusion, open lips and chin quiver 9 .Data were analyzed and interpreted as from relevant literature on the subject using descriptive statistics and were organized in tables.Ethical-legal aspects of Resolution 466/2012 10 of the Department of Health were complied with and the study was approved by the Institution's Ethics Committee under protocol 390/2010.

RESULTS
Categorical variables of newborns participating in the study were exposed for analysis of results, which are: days of life, gender, weight at birth, gestational age and Apgar score.
Table 1 shows distribution of NB participating in the study according to socio-demographic variables.With regard to gender there is equality being 50% females and 50% males.
As to days of life there has been predominance (80.8%) of one to seven days; and 92.3% were preterm neonates, that is, with gestational age between 20 and 37 weeks, which has contributed to high neonatal mortality indices.With regard to the number of puncture attempts, it has varied from one to four, being that in 19 NB there has been success in the first attempt.However, it should be emphasized that in seven it was necessary 2 to 4 attempts to be successful, especially due to NB general clinical status, as well as to nurse's technical skills, thus the importance of nurses reflecting about the practice of humanistic care and prevention of pain when assisting NB at risk.

DISCUSSION
For data analysis and discussion, references were used which characterized the importance of such data to sensitize health professionals acting in NICU when performing painful procedures in NB.With regard to gender, there has been equal number of females and males.However, a study 11 has shown a birth differential according to gender, with always a higher number of male births, regardless of the level of development of the studied area.A different study 12 states that male gender was considered a risk factor for death, due to less maturity of organs and higher incidence of RDS, considered the major reason for NB admission to NICU; while there are higher survival rates among female NB.Considering gestational age, there have been 92.3% of NB classified as preterm, or those with gestational age below 37 weeks.
As to weight, this is recognized as one of the best indicators of neonatal morbidity and mortality risk, since it is pertinent to say that 20 million low weight NB are born in the world every year, many as consequence of premature delivery, contributing to the high neonatal mortality rate still existing in several regions, especially in developing countries.Recent data refer that in Brazil, childhood mortality rate has considerably decreased in the last decades; however indices are still high: approximately 23.6 deaths per thousand births, especially due to prematurity and low weight at birth 13 .When assessing Apgar scores in the fifth minute of life, it is observed that all NB had Apgar scores between 5 and 10, classifying them as mild suffocation (5 to 7) or no suffocation (8 to 10), suggesting a positive prognosis with minor respiratory effort in the first minutes of life.The Apgar score provides accurate evaluation for the use of fast neonatal resuscitation procedures, still in the birthing room, because it has five parameters related to perinatal hypoxia such as: HR, breathing, muscle tone, reflex irritability and skin color, in a scale of zero to 10 and if score is below seven fetal hypoxia is diagnosed 14 .As to respiratory support, it was observed that 88.5% NB were under IMV, which could be associated to clinical instability and prematurity, thus justifying the need for respiratory support, which is vital to improve respiratory function and gases exchanges, especially for preterm NB.IMV is considered an invasive procedure predisposing NB to risks of iatrogenesis, bronchopulmonary dysplasia, infections and longer NICU stay.These circumstances may favor the possibilities of consequences arising from NB physiological conditions themselves or caused by therapy, environment and other factors, such as witnessing painful procedures such as blood gases analysis 2,15 .Pain as a subjective sign, added to the difficulty in verbalizing it, conditions health professionals, especially NICU nurses, to be alert to behavioral and physiological changes following painful episodes.So, blood gases analysis is em-phasized as a painful procedure deserving further sensitization of health professionals to NB responses and then to use pain evaluation tools, such as facial mimic scale (NFCS) and intervene to relieve NB pain 6 .So, it is important that NICU nurses provide holistic and humanized care to NB at risk during blood gases analysis procedures, that is, the assistance should not be exclusively directed to operational technical approaches, but also to a technology associated to reassurance 16 .With regard to NFCS scores, most NB (96.1%) had enough manifestations to characterize pain during blood gases analysis.However, it is important to emphasize that two were sedated, with only one showing pain characteristics according to NFCS.
A study 7 has shown that there are no absolute indications for sedation and analgesia in the neonatal period, however stresses that it might be adequate for pain relief, especially for NB with potentially painful diseases and/or submitted to invasive procedures, surgical or not, such as chest drainage, elective tracheal intubation, patients with necrotizing enterocolitis and especially patients under IMV needing daily blood gases analysis.
Several physiological indicators may be used to evaluate, quantify and qualify pain.These variables include: heart and respiratory rates, blood pressure, SatO 2 , hand sweating, and vagal tone among others.However, such physiological indicators are not specifically related to pain 17 .It was observed that 50% of newborns had HR changes during blood gases analysis and 34.7% have changed SatO 2 .Such findings are in line with authors 18 who state that tachycardia is among most common human body responses to acute pain.However, investigators 17 refer that no significant changes in HR and SatO 2 were observed before and after painful procedures, which indicates that HR and SatO 2 alone to evaluate pain were not valid to identify NB submitted to a painful procedure.
During the exam, it was observed that 73% of NB undergoing blood gases analysis were successfully punctured in the first attempt; however seven of them needed two to four attempts, thus showing the importance of nurses technical skills, in addition to scientific knowledge related to NB anatomic and physiological conditions, such as sensibility and interaction with them, thus being able to notice facial and physiological manifestations during painful procedures.Other strategies may be used, such as placing the NB close to the mother to decrease pain, in addition to non-pharmacological interventions 18 .
As implication for assisting NB at risk admitted to neonatal unit, we believe it is of paramount importance the use of strategies to minimize NB pain during blood gases analysis.So, we suggest the use of behavioral scales to evaluate NB pain, such as NFCS.This scale allows professionals, when carrying out a painful procedure, to be sensitive to the onset of physiological or behavioral manifestations so as to minimize pain discomfort and complications from such manifes-tations.As limitation of our study, we stress the difficulty to generalize that the NFCS scale is adequate to evaluate NB pain during blood gases analysis, since such scale was used in association with physiological variables for such evaluation.

CONCLUSION
When NB physiological parameters were compared before and during arterial puncture, there have been face manifestations of pain in all NB, in addition to physiological changes such as decreased SatO 2 levels and increased HR, according to NFCS scale, showing that although unable to verbalize they are able to show changes to express pain felt during arterial puncture.

Table 2 .
Distribution of newborns according to face manifestations of pain by means of the Neonatal Facial Activity Coding scale.Fortaleza-CE, Apr-May/2010

Table 2
against the traditional idea that NB are unable to feel pain.Table3shows physiological changes during blood gases analysis where it is observed that there have been changes in HR and SatO 2 .
NB had not such manifestations since he was under sedation, however different from the other NB who, in spite of being sedated, has shown some pain manifestations.It should be emphasized that most NB had manifestations according to NFCS scale, showing that although being unable to verbalize, they are able to show behavioral and physiological changes to express pain felt during arterial puncture, thus going

Table 3 .
Distribution of newborns with regard to heart rate and oxygen saturation before blood gases analysis procedure.