What Facial Features Does the Pediatrician Look to Decide That a Newborn Is Feeling Pain?

OBJECTIVE: The study aimed to analyze the gaze fixation of pediatricians during the decision process regarding the presence/absence of pain in pictures of newborn infants. STUDY DESIGN: Experimental study, involving 38 pediatricians (92% females, 34.6 ± 9.0 years, 22 neonatologists) who evaluated 20 pictures (two pictures of each newborn: one at rest and one during a painful procedure), presented in random order for each participant. The Tobii-TX300 equipment tracked eye movements in four areas of interest of each picture (AOI): mouth, eyes, forehead, and nasolabial furrow. Pediatricians evaluated the intensity of pain with a verbal analogue score from 0 to 10 (0 = no pain; 10 = maximum pain). The number of pictures in which pediatricians fixed their gaze, the number of gaze fixations, and the total and average time of gaze fixations were compared among the AOI by analysis of variance (ANOVA). The visual-tracking parameters of the pictures' evaluations were also compared by ANOVA according to the pediatricians' perception of pain presence: moderate/severe (score = 6-10), mild (score = 3-5), and absent (score = 0-2). The association between the total time of gaze fixations in the AOI and pain perception was assessed by logistic regression. RESULTS: In the 20 newborn pictures, the mean number of gaze fixations was greater in the mouth, eyes, and forehead than in the nasolabial furrow. Also, the average total time of gaze fixations was greater in the mouth and forehead than in the nasolabial furrow. Controlling for the time of gaze fixation in the AOI, each additional second in the time of gaze fixation in the mouth (odds ratio [OR]: 1.26; 95% confidence interval [CI]: 1.08-1.46) and forehead (OR: 1.16; 95% CI: 1.02-1.33) was associated with an increase in the chance of moderate/severe pain presence in the neonatal facial picture. CONCLUSION: When challenged to say whether pain is present in pictures of newborn infants' faces, pediatricians fix their gaze preferably in the mouth. The longer duration of gaze fixation in the mouth and forehead is associated with an increase perception that moderate/severe pain is present. KEY POINTS: · Neonatal pain assessment is intrinsically subjective.. · Visual tracking identifies the focus of attention of individuals.. · Adults' gaze in neonates' mouth and forehead is associated with pain perception..

Neonatal procedural pain can be assessed by computer software that has good sensitivity and specificity to detect facial movements.

AIM: The difficulty in assessing pain during the neonatal period is one of the main obstacles for appropriate analgesia in intensive care units. The aim of this study was to develop and validate computer software to monitor neonatal facial movements of pain in real time. METHODS: The software was developed in the Delphi integrated development environment and provides real-time image analysis during monitoring, based on image recognition of pain-related facial actions. To validate the software performance, facial images were obtained during the monitoring of 30 neonates who were subjected to painful procedures related to daily care management. Of the 5644 images identified and analysed by the software, 360 images - 12 per infant - were randomly selected and assessed by six healthcare professionals with experience of recognising neonatal pain. RESULTS: The agreement between the examiners and the software assessment was excellent (κ = 0.975). The software exhibited 85% sensitivity and 100% specificity in detecting neutral facial expressions in the resting state and 100% sensitivity and specificity in detecting pain during painful procedures. CONCLUSION: It is possible to assess neonatal procedural pain using computer software that has good sensitivity and specificity to detect facial movements.

Human vs machine towards neonatal pain assessment: A comprehensive analysis of the facial features extracted by health professionals, parents, and convolutional neural networks.

Neonates are not able to verbally communicate pain, hindering the correct identification of this phenomenon. Several clinical scales have been proposed to assess pain, mainly using the facial features of the neonate, but a better comprehension of these features is yet required, since several related works have shown the subjectivity of these scales. Meanwhile, computational methods have been implemented to automate neonatal pain assessment and, although performing accurately, these methods still lack the interpretability of the corresponding decision-making processes. To address this issue, we propose in this work a facial feature extraction framework to gather information and investigate the human and machine neonatal pain assessments, comparing the visual attention of the facial features perceived by health-professionals and parents of neonates with the most relevant ones extracted by eXplainable Artificial Intelligence (XAI) methods, considering the VGG-Face and N-CNN deep learning architectures. Our experimental results show that the information extracted by the computational methods are clinically relevant to neonatal pain assessment, but yet do not agree with the facial visual attention of health-professionals and parents, suggesting that humans and machines can learn from each other to improve their decision-making processes. We believe that these findings might advance our understanding of how humans and machines code and decode neonatal facial responses to pain, enabling further improvements in clinical scales widely used in practical situations and in face-based automatic pain assessment tools as well.

Pediatricians' focus of sight at pain assessment during a neonatal heel puncture.

OBJECTIVE: To evaluate the focus of pediatricians' gaze during the heel prick of neonates. METHODS: Prospective study in which pediatricians wearing eye tracker glasses evaluated neonatal pain before/after a heel prtick. Pediatricians scored the pain they perceived in the neonate in a verbal analogue numerical scale (0=no pain; 10=maximum pain). The outcomes measured were number and time of visual fixations in upper face, lower face, and hands, in two 10-second periods, before (pre) and after the puncture (post). These outcomes were compared between the periods, and according to pediatricians' pain perception: absent/mild (score: 0-5) and moderate/intense (score: 6-10). RESULTS: 24 pediatricians (31 years old, 92% female) evaluated 24 neonates. The median score attributed to neonatal pain during the heel prick was 7.0 (Interquartile range: 5-8). Compared to pre-, in the post-periods, more pediatricians fixed their gaze on the lower face (63 vs. 92%; p=0.036) and the number of visual fixations was greater on the lower face (2.0 vs. 5.0; p=0.018). There was no difference in the number and time of visual fixations according to the intensity of pain. CONCLUSIONS: At bedside, pediatricians change their focus of attention on the neonatal face after a painful procedure, focusing mainly on the lower part of the face.

Looking at neonatal facial features of pain: do health and non-health professionals differ?

OBJECTIVE: To analyze the regions that trigger the attention of adults' gaze when assessing pain in newborn infants' pictures and to verify if there are differences between health and non-health professionals. METHOD: Experimental study with 84 health professionals and 59 non-health professionals, who evaluated two images of 10 neonates, one at rest and the other during a painful procedure. Each image was shown for 7 seconds on a computer screen, while eye movements were tracked by the Tobii TX300 EyeTracker. After evaluating each image, participants gave a score from 0 (absent pain) to 10 (maximum pain), according to their perception of neonatal pain. For each image, the number and total time of gaze fixations in the forehead, eyes, nasolabial furrow, and mouth were studied. Comparisons between both groups of adults were made by an intraclass correlation coefficient, Student's t-test, and Bland Altman graphic. RESULTS: Health professionals (93% female; 34 ± 9 years old), compared to non-health professionals (64% female; 35 ± 11 years old), gave lower scores for images at rest (0.81 ± 0.50 vs. 1.59 ± 0.76; p = 0.010), with no difference for those obtained during the painful procedure (6.98 ± 1.08 vs. 6.73 ± 0.82). There was a strong or almost perfect correlation for the number of fixations in the mouth, eyes, forehead, and for the total fixation time in the eyes and forehead. CONCLUSIONS: Adults, irrespective of their profession, showed a homogeneous gaze pattern when evaluating pictures of neonates at rest or during a painful procedures.

Identification of pain in neonates: the adults' visual perception of neonatal facial features.

OBJECTIVE: To verify the visual attention of adults when assessing neonatal pain. STUDY DESIGN: 143 adults (59% health professionals) evaluated 20 pictures (2 pictures of 10 neonates' faces: at rest; during a painful procedure). Tobii-TX300 tracked the participants' eyes movement. For each picture, adults scored pain intensity (0 = no pain; 10 = maximum). Latent classes analysis was applied by cognitive diagnosis models-GDINA with two attributes (knowledge of pain presence/absence). Variables associated with belonging to the class of adults that correctly identified pictures of newborns with/without pain were identified by logistic regression. RESULTS: To identify neonatal pain, adults look at the mouth, eyes, and forehead in facial pictures. The latent class analysis identified four classes of adults: those that identify painful/painless neonates (YY-Class; n = 80); only painful neonates (n = 28); only painless neonates (n = 34) and none (n = 1). Being a health professional (OR: 2.29; 95% CI: 1.16-4.51), and each look at the nasolabial furrow (2.07; 1.19-3.62) increased the chance of belonging to the YY-class. CONCLUSIONS: Being a health professional and the visual fixation at the nasolabial furrow helped to identify the presence/absence of neonatal pain.

Pediatricians' focus of sight at pain assessment during a neonatal heel puncture / Foco do olhar do pediatra na avaliação da dor neonatal durante uma punção de calcanhar

ABSTRACT Objective: To evaluate the focus of pediatricians' gaze during the heel prick of neonates. Methods: Prospective study in which pediatricians wearing eye tracker glasses evaluated neonatal pain before/after a heel prtick. Pediatricians scored the pain they perceived in the neonate in a verbal analogue numerical scale (0=no pain; 10=maximum pain). The outcomes measured were number and time of visual fixations in upper face, lower face, and hands, in two 10-second periods, before (pre) and after the puncture (post). These outcomes were compared between the periods, and according to pediatricians' pain perception: absent/mild (score: 0-5) and moderate/intense (score: 6-10). Results: 24 pediatricians (31 years old, 92% female) evaluated 24 neonates. The median score attributed to neonatal pain during the heel prick was 7.0 (Interquartile range: 5-8). Compared to pre-, in the post-periods, more pediatricians fixed their gaze on the lower face (63 vs. 92%; p=0.036) and the number of visual fixations was greater on the lower face (2.0 vs. 5.0; p=0.018). There was no difference in the number and time of visual fixations according to the intensity of pain. Conclusions: At bedside, pediatricians change their focus of attention on the neonatal face after a painful procedure, focusing mainly on the lower part of the face.

RESUMO Objetivo: Avaliar o foco do olhar do pediatra durante a punção do calcanhar de neonatos. Métodos: Estudo prospectivo no qual pediatras, utilizando óculos de rastreamento visual, avaliaram a dor neonatal antes/depois de uma punção de calcanhar. Os pediatras pontuaram a dor de acordo com a sua percepção por meio de uma escala analógica verbal (0=sem dor; 10=dor máxima). Os desfechos analisados foram o número e o tempo das fixações visuais na face superior, face inferior e mãos, em dois períodos de 10 segundos, antes (PRÉ) e depois da punção (PÓS). Os resultados foram comparados entre os períodos e segundo a percepção da dor do pediatra: ausente/leve (escore: 0-5) e moderada/grave (escore: 6-10). Resultados: Vinte e quatro pediatras (31 anos, 92% sexo feminino) avaliaram 24 neonatos. A mediana do escore atribuído à dor do recém-nascido durante a punção do calcanhar foi 7,0 (intervalo interquartil: 5-8). Comparado ao período PRÉ, no período PÓS, o maior número de pediatras fixou o olhar na face inferior (63 vs. 92%; p=0,036) e o número de fixações visuais foi maior na face inferior (2,0 vs. 5,0; p=0,018). Não houve diferença no número e no tempo das fixações visuais de acordo com a intensidade da dor. Conclusões: À beira do leito, os pediatras mudam seu foco de atenção visual na face do recém-nascido após um procedimento doloroso, focando o olhar principalmente na parte inferior da face.

Looking at neonatal facial features of pain: do health and non-health professionals differ?

Abstract Objective: To analyze the regions that trigger the attention of adults' gaze when assessing pain in newborn infants' pictures and to verify if there are differences between health and non-health professionals. Method: Experimental study with 84 health professionals and 59 non-health professionals, who evaluated two images of 10 neonates, one at rest and the other during a painful procedure. Each image was shown for 7 seconds on a computer screen, while eye movements were tracked by the Tobii TX300 EyeTracker. After evaluating each image, participants gave a score from 0 (absent pain) to 10 (maximum pain), according to their perception of neonatal pain. For each image, the number and total time of gaze fixations in the forehead, eyes, nasolabial furrow, and mouth were studied. Comparisons between both groups of adults were made by an intraclass correlation coefficient, Student's t-test, and Bland Altman graphic. Results: Health professionals (93% female; 34 ± 9 years old), compared to non-health professionals (64% female; 35 ± 11 years old), gave lower scores for images at rest (0.81 ± 0.50 vs. 1.59 ± 0.76; p = 0.010), with no difference for those obtained during the painful procedure (6.98 ± 1.08 vs. 6.73 ± 0.82). There was a strong or almost perfect correlation for the number of fixations in the mouth, eyes, forehead, and for the total fixation time in the eyes and forehead. Conclusions: Adults, irrespective of their profession, showed a homogeneous gaze pattern when evaluating pictures of neonates at rest or during a painful procedures.

Inter-observer agreement in the identification of pain faces in full-term and late preterm newborns: cross-sectional study / Concordância interavaliadores na identificação de faces de dor de recém-nascidos a termo e pré-termo tardio: estudo transversal

ABSTRACT BACKGROUND AND OBJECTIVES: Difficulty in neonatal assessment is a challenge for the development of pain prevention and treatment strategies. The objective of this study was to analyze the agreement among health professionals in the identification of facial pain movements in images of neonates submitted or not to a painful procedure and to evaluate the discriminatory capacity of these facial movements regarding the presence of pain. METHODS: Cross-sectional study. Six health professionals trained in neonatal pain assessment evaluated 30 images of newborns undergoing a painful procedure and 30 images of the same newborns at rest, without pain. Each professional evaluated five facial movements that are part of the Neonatal Facial Coding System. Sensitivity, specificity, and positive and negative predictive values were determined. Agreement among professionals was assessed using the kappa coefficient. RESULTS: The six observers correctly assessed 94±9% of the images obtained at rest as absence of pain and 88±28% of the images obtained during the painful procedure as presence of pain. Protruding forehead, narrowed eyelid cleft, deepened nasolabial furrow, and open mouth showed high sensitivity, specificity, and positive and negative predictive values in the diagnosis of pain, with values between 78-90%. The inter-observer agreement for all 60 images showed a kappa coefficient of 0.60 (95%CI 0.55-0.66). CONCLUSION: The evaluation of the forehead, eyelid, nasolabial furrow and mouth of newborns showed high sensitivity and specificity to discriminate the presence and absence of pain in static images. The agreement between the evaluators in identifying facial movements related to the expression of pain in newborns was moderate.

RESUMO JUSTIFICATIVA E OBJETIVOS: A dificuldade na avaliação da dor do recém-nascido é um desafio para o desenvolvimento de estratégias de prevenção e tratamento da dor. O objetivo deste estudo foi analisar a concordância entre profissionais de saúde na identificação de movimentos faciais de dor em imagens de recém-nascidos submetidos ou não a um procedimento doloroso e a capacidade discriminatória quanto à presença de dor desses movimentos faciais. MÉTODOS: Estudo transversal. Seis profissionais de saúde treinados na avaliação da dor neonatal avaliaram 30 imagens de recém-nascidos submetidos a um procedimento doloroso e 30 imagens em repouso dos mesmos recém-nascidos, sem dor. Cada profissional avaliou cinco movimentos faciais que fazem parte do Sistema de Codificação Facial Neonatal. Sensibilidade, especificidade e valores preditivos positivos e negativos foram determinados. A concordância interavaliadores foi avaliada pelo coeficiente kappa. RESULTADOS: Os seis observadores avaliaram corretamente 94±9% das imagens obtidas em repouso como ausência de dor e 88±28% das imagens obtidas durante o procedimento doloroso como presença de dor. Fronte saliente, fenda palpebral estreitada, sulco nasolabial aprofundado e boca aberta mostraram alta sensibilidade, especificidade e valores preditivos positivo e negativo no diagnóstico de dor, com valores entre 78 e 90%. A concordância interavaliadores para todas as 60 imagens mostrou um kappa 0,60 (IC95%0,55-0,66). CONCLUSÃO: A avaliação da fronte, pálpebra, sulco nasolabial e boca de recém-nascidos mostrou alta sensibilidade e especificidade para discriminar a presença e ausência de dor em imagens estáticas. A concordância interavaliadores na identificação de movimentos faciais relacionados à expressão da dor em recém- -nascidos foi moderada.