Este trabalho discute as vicissitudes da constituição do sujeito do desejo na clínica do bebê pré-termo, constituição agenciada pela articulação das funções materna e paterna que atualizam para um sujeito a estrutura da linguagem, isto é, que articulam o desejo à dimensão da falta. Na clínica do bebê pré-termo o investimento desejante que sustenta a aposta simbólica que preside a inscrição do infans no dizer e no desejo do Outro é posto à prova, pois os pais, primeiros representantes do Outro (simbólico) para o recém-nascido, são confrontados de maneira intempestiva com a dualidade da vida e da morte. A escuta dos pais durante a hospitalização de seus bebês numa unidade de tratamento intensivo neonatal revela que a construção do laço primordial entre pais e filhos sofre o impacto do discurso técnico-científico, pois o lugar e o saber dos pais são inicialmente deslocados pelo saber médico e sancionados como insuficientes para cuidar da criança. Os fragmentos das falas dos pais apresentados neste trabalho são analisados à luz dos ensinamentos da psicanálise. Essa análise mostra que a escuta dos pais humaniza esse nascimento, pois implica-os numa elaboração psíquica que atenua a angústia e o sentimento de desamparo que acompanha esses nascimentos, visto que o bebê pré-termo produz uma inquietante estranheza em seus pais. O apoio psíquico fornecido a eles favorece a retificação do olhar fundador em relação ao bebê, minimizando o impacto das separações precoces que ameaçam a construção dos laços de amor e de desejo entre pais e filhos, a qual sabemos ser uma prerrogativa da saúde psíquica. / This work discusses the vicissitudes of the constitution of the subject of the desire in the clinic of preterm babies, a constitution that is promoted by the articulation of the motherly and fatherly functions that update to a subject the structure of language, that is, that articulates the desire with the dimension of lack. In the preterm baby clinic, the desiring investment that sustains the symbolic anticipation that presides the inscription of the infans in the discourse and in the desire of the Other is challenged, since parents, the first representatives of the (symbolic) Other for the newborn, are confronted in an untimely way with the duality of life and death. The hearing of the parents during the hospitalization of their babies in an neonatal intensive-care unit reveals that the construction of the primordial bond between parents and children suffers the impact of the techno-scientific discourse, since the place and the knowledge of parents are initially displaced by the medical knowledge and sanctioned as being insufficient to take care of the child. The fragments of the testimonials of the parents presented in this work are analyzed at the light of the teachings of psychoanalysis. This analysis shows that the hearing of the parents humanizes this birth, because it involves them in a psychical elaboration that attenuates the anguish and the feeling of helplessness that follows these births, considering that the premature baby produces a disturbing strangeness in its parents. The psychic support offered to them favors the rectification of the founding gaze in relation to the baby, thus minimizing the impact of the precocious separations that threaten the construction of the bonds of love and desire between parents and children that we know as being a prerogative of the psychic health.

Objetivos: Verificar os efeitos do acompanhamento fonoaudiológico no desenvolvimento das habilidades de alimentação do bebê no primeiro ano de vida. Métodos: Estudo de coorte prospectivo realizado entre abril de 2010 a maio de 2011, com binômios mãe/bebê inicialmente em uma maternidade na zona sul do município de São Paulo e acompanhados durante 12 meses. O grupo estudo foi constituído de RNs com 24 a 48 horas de vida, filhos de mães primigestas e maiores de 18 anos de idade, com escore 11 de acordo com o Escala de Avaliação Motora-Oral em Berçário, submetidos a acompanhamento fonoaudiológico. O grupo controle foi obtido de bebês nascidos na mesma maternidade, com APGAR 9 e > 2.500g., de mães com mesmas características, contatadas aos 12 meses. Resultados: A prevalência de desmame foi semelhante em ambos os grupos, entretanto o aleitamento materno apresentou Md de 7m e 5m nos grupos estudo e controle respectivamente (p=0,04). A introdução da consistência alimentar sólida foi em média 7,8m e 9,6m (p<0,01). Os copos de transição foram utilizados por 92,9% e 70,2% (p=0,01) e canudos por 59,5% e 27,7% (p=0,003). A prevalência do uso de chupeta foi 54,0% e 27,7% (p=0,01) aos 12 meses. Conclusões: O grupo acompanhado mostrou melhora no desempenho do aleitamento materno aos 2 meses. Comparado ao grupo controle, apresentou desmame mais tardio; redução do tempo de introdução da consistência sólida, mais utilização dos utensílios e menor prevalência do uso de chupeta aos 12m / Objectives: Investigate the effects of speech therapy in the development of feeding skills of the baby in the first year of life Methods: A prospective cohort study between April 2010 and May 2011 whit mother / baby binomial in a maternity hospital in the southern area of São Paulo and followed during 12 months. The study group consisted of newborns with 24 to 48 hours of life, children of primigravid mothers older than 18 years of age, wich had a score 11 according to the Oral-Motor in Nursery Assessment Scale undergoing speech therapy. The control group was obtained from babies born at the same hospital, with Apgar 9 and > 2,500 g, from mothers with similar characteristics who were contacted at 12 months. Results: The prevalence of weaning was similar in both groups, however breastfeeding presented Md of 7m and 5m in the study and control groups respectively (p = 0.04). The introduction of solid consistency food was at 7.8 m and 9.6 m (p <0.01). The glass transition were used by 92.9% and 70.2% (p = 0.01) and straws by 59.5% and 27.7% (p = 0.003). The prevalence of pacifier use was 54.0% and 27.7% (p = 0.01) at 12 months. Conclusions: The study group, compared to the control, presented: improvement in the performance of breastfeeding at 2 months, later weaning, reducing time for introduction of solid consistency food, wider use of utensils and lower prevalence of pacifier use at 12m

Leveduras da mucosa oral, de cateter e de sangue de neonatos internados na UTIN (Unidade de Terapia Intensiva Neonatal) por período de 9 meses, foram avaliadas quanto ao perfil molecular pela técnica de PFGE. Dos 125 neonatos internados, 23 (18,4%) apresentaram leveduras na mucosa oral, sangue e cateter. Destes pacientes, obtivemos 54 amostras de leveduras, sendo 36 (66,7%) isoladas da colonização oral; 12 (22,2%) de sangue, seis (11,1%) de cateter. C. albicans foi a mais freqüente dentre as amostras isoladas da mucosa oral e sepse. C. parapsilosis foi a mais isolada dentre as amostras de cateter. Todas as amostras foram consideradas sensíveis aos antifúngicos. Estas amostras apresentaram atividade de pelo menos uma exoenzima. Dentre os 12 casos de sepse, 83,4% (10/12) foram causadas por espécies de Candida, sendo que, destas 10 candidemias, 60% (6/10) estiveram associadas com colonização oral prévia pela mesma espécie e perfil genotípico. A mortalidade devido a infecção sistêmica (septicemia) por leveduras,no período do estudo, foi de 91.6% . / Yeasts isolated from the oral mucosa, catheter and blood of neonates in na NICU (neonatal intensive care unit) over a period of 9 months, were were evaluated in regard to the molecular profile by PFGE technique. Of the 125 neonates studied, 23 (18.4%) presented yeast in their oral mucosa, blood, or catheter. From these 23 neonates, 54 samples of yeast were obtained; 36 (63.7%) from oral colonization, 12 (22.2%) from the blood, and 6 (11.1%) from the catheter. The most frequently encountered species among the samples isolated from the oral mucosa and blood was C. albicans; while C. parapsilosis was the species found most frequently among the samples obtained from catheters. All the samples were considered susceptible to antifungal agents tested. The samples presented activity of at least one exoenzyme. Among the 12 cases of sepsis, 10 (83.4%) were caused by species of Candida, and of these 10 cases, 6 (60%) were associated with previous oral colonization by the same species and genotypic profile. The mortality rate due to septicemia by yeasts was 91.6%.

La population néonatale est la population pédiatrique la plus vulnérable car immature et celle ayant probablement les besoins en médicaments les plus importants, compte tenu de la spécificité des pathologies néonatales. Pour autant, un grand nombre de médicaments sont prescrits en dehors des conditions de leur AMM, ne permettant pas leur utilisation optimale. Cela est lié notamment aux difficultés de la recherche clinique chez le nouveau-né. L’objectif de cette thèse est d’analyser les différentes étapes de l’évaluation des médicaments chez le nouveau-né et de discuter les méthodes permettant de les optimiser, en centrant la réflexion sur la classe des médicaments anti-infectieux. En effet, ces médicaments sont parmi les plus prescrits hors AMM chez le nouveau-né, prématuré et à terme, bien qu’ils soient commercialisés depuis de nombreuses années. Nos travaux ont porté sur les différentes étapes de leur évaluation, illustrées chacune par un exemple. 1) Analyse des spécificités de la population néonatale et des pratiques d’utilisation des médicaments, illustrées par l’enquête Européenne sur l’utilisation de la ciprofloxacine et du fluconazole dans les unités de soins intensifs néonatales. Cette enquête a mis en évidence la grande variabilité des pratiques entre les pays mais aussi entre les centres d’un même pays, 2) Recueil et analyse des données disponibles, illustrés par la revue exhaustive de la littérature sur l’utilisation de la ciprofloxacine pour le traitement d’infections néonatales à germes Gram négatif, 3) Détermination de la posologie adéquate. L’implémentation d’outils de modélisation et de simulation de données est particulièrement préconisée chez le nouveau-né. La validation de ces modèles est importante, illustrée ici par une étude d’évaluation externe des modèles pharmacocinétiques de population de la vancomycine chez le nouveau-né. 4) Conception et réalisation des essais cliniques illustrées par l’exemple du développement clinique de la ciprofloxacine en néonatologie. La revue de la littérature sur les essais contrôlés randomisés évaluant les antibiotiques chez le nouveau-né a montré que la qualité des résultats de ces essais était globalement faible. L’analyse des obstacles à leur réalisation a permis de discuter les alternatives méthodologiques afin de contourner les difficultés pratiques, cliniques et éthiques sous-jacentes. / Neonates represent the most vulnerable paediatric population and probably the one with the greatest needs in medicines with regard to the specificities of neonatal diseases. Nevertheless, the off-label prescribing of drugs with no marketing authorisation, consequentlywithout information for their proper use, is widespread in neonatology. This situation is related to the difficulties of clinical research encountered in this population. The objective of this thesis is to analyse the different steps of drug development in neonates and to discuss the possible methods to optimize drug evaluation. To illustrate this development, we expose examples from the evaluation of anti-infective agents in neonatology. These drugs are very often concerned by a use outside their product licence in term and preterm neonates, despite the fact that they have been marketed for many years. This thesis includes studies concerning the different steps of their development illustrated by examples. 1) Evaluation of the specificities of the neonatal population and of drug prescribing. This was demonstrated by the results of a European survey on the use of ciprofloxacin and fluconazole in neonatal intensive care units. The surveys’ results underline the considerable variability in drug prescribing observed between different countries but also between units in the same country. 2) Analysis of available data, illustrated by the systematic review of the literature on ciprofloxacin use for the treatment of Gram negative neonatal infections, 3) Definition of optimal dosing. Use of modelling and data simulation approaches should be particularly favoured in neonatal drug research. Correct validation of models should be performed as illustrated by the external validation of vancomycin population pharmacokinetic models. 4) Design and implementation of clinical trials. This step has been illustrated by the clinical development of ciprofloxacin in neonatology. The review of all randomised controlled trials evaluating the therapeutic and prophylactic use of antibiotics in neonates showed that these trials are poorly designed, conducted and reported. Different methods of evaluation should be considered and further developed to circumvent the difficulties in drug evaluation and ensure the efficient and safe use of antibiotics.

Maternal and newborn health is one of the main indicators of a good health system. The study wished to develop a strategy to improve the referral system for maternal and newborn care. To identify issues for improvement, the researcher explored the appropriateness of referrals, referral pathways and challenges, and provider costs for maternal and newborn care at health centres and hospitals levels. The researcher selected a sequential explanatory mixed method research design. Two primary hospitals and six health centres were purposively selected for participation. The first phase collected quantitative data by reviewing the health facilities’ medical records for services provided and health service costing, respectively. Data collection covered one Ethiopian fiscal year (8 July 2017 to 7 July 2018). Based on the existing human resource arrangement and care needs, the health service costing found that a single midwife at health centre level spent half of the expected time for delivery care. The cost estimates of various types of care delivery care indicated that delivery care at health centre and hospital levels cost $27.5 to $30.2, and $34.7 to $37.8, respectively. The primary hospitals incurred four times the cost for newborn intensive care units and Caesarean sections compared to normal delivery care. In the second phase, the researcher collected qualitative data from 26 purposively selected key informants in interviews. The findings indicated that the selected hospitals and health centres had a referral system, but several factors impeded its effective implementation. Knowledge of referral pathways determined the referral practices at the lower level of the system. The number of inappropriate referrals to primary hospitals indicated a need to mobilize and educate the community on the services available and protocols of care. In general, most referrals could have been managed at health centre level. Emergency medical transportation is a critical component of the referral system; delays in transportation determine the outcome of care at hospital level. Ambulance management was generally poor, lacked a tracking system, and was negatively affected by confusion and lack of coordination between facilities. The available ambulances were not well equipped or well-staffed for emergency management. Moreover, there were frequent breakdowns due to limited budget for maintenance and running costs. The quality of maternal care depends on the quality of the labour monitoring. However, partograph utilization was not consistently practised. Admitted cases were not properly monitored because of the high caseload and limited supervision support. In many cases, healthcare professionals tended to “treat charts” rather than promote evidencebased practice while providing care. The quality of practice was challenged by insecurity in the working environment but strengthened by good teamwork and available consultation support. The implementation of the existing referral system depended on the people involved; the use of performance indicators; follow up by management, and an accountability framework. The findings of the two phases of the study and review of other countries’ experiences on the identified problems, led to the development of draft strategy and then a consultation with relevant experts produced the final strategy. The strategy includes interventions to improve the practices at the sending and receiving facilities as well as suggestions to improve the communication, transportation and overall governance system. Then, taking into consideration all the phases of the study, the researcher makes recommendations for practice and further research. / Health Studies / D. Litt. et Phil. (Healht Studies)

This review will focus on a systems medicine approach to neonatal abstinence syndrome (NAS). Systems medicine utilizes information gained from the application of “omics” technology and bioinformatics (1). The omic approaches we will emphasize include genomics, epigenomics, proteomics, and metabolomics. The goals of systems medicine are to provide clinically relevant and objective insights into disease diagnosis, prognosis, and stratification as well as pharmacological strategies and evidence-based individualized clinical guidance. Despite the increasing incidence of NAS and its societal and economic costs, there has been only a very modest emphasis on utilizing a systems medicine approach, and this has been primarily in the areas of genomics and epigenomics. As detailed below, proteomics and metabolomics hold great promise in advancing our knowledge of NAS and its treatment. Metabolomics, in particular, can provide a quantitative assessment of the exposome, which is a comprehensive picture of both internal and external environmental factors affecting health.

Introduction. L’exposition à la douleur répétée pendant la période néonatale a des effets nocifs sur le développement neurologique des nouveau-nés prématurés et peut contribuer à une douleur prolongée. Une taxonomie précise de la douleur néonatale est absente due à l’existence d’une terminologie ambigüe qui persiste en néonatologie. Par conséquent, l’évaluation et la gestion de ce type de douleur dans le milieu clinique sont sous-optimales. Objectif. Établir la portée, l'étendue et la nature des écrits scientifiques liées à la douleur prolongée des nouveau-nés prématurés hospitalisés dans l’unité de soins intensifs néonatals (USIN), par le biais d’une revue de la portée. Méthodologie. La revue de la portée suit les lignes directrices du Joanna Briggs Institute (JBI). Une stratégie de recherche a été effectuée dans les bases de données CINAHL, PubMed, Medline, Web of Science, Google Scholar, GeryLit.org et Grey Source Index. Résultats. La revue de la portée a identifié 78 articles pertinents qui abordaient des définitions (n=25), des indicateurs (n=37), des contextes de soins (n=47), des outils d’évaluation (n=49), des conséquences (n=29) et des interventions (n=21) pour soulager la douleur prolongée néonatale. La revue soutien que les contextes de soins des nouveau-nés prématurés devraient toujours être considérés indépendamment de la présence ou non d’indicateurs de la douleur prolongée afin de guider l’évaluation et le soulagement de la douleur prolongée. Conclusion. Ce mémoire a recensé les éléments essentiels de la douleur prolongée et a permis d’émettre des recommandations pour la pratique, la formation, la gestion et le recherche infirmière, guidé par le cadre théorique de Huth et Moore (1998). / Introduction. Exposure to repetitive pain during the neonatal period has been shown to have important long-term effects on the neurodevelopment of the premature neonate and can contribute to experienced prolonged pain. Since a uniform taxonomy of neonatal prolonged pain is still lacking to this day in neonatology, prolonged pain management remains suboptimal in neonatal intensive care units (NICU). Aim. This master’s thesis aims to determine the scope, extent, and nature of the available literature on prolonged pain in premature neonates hospitalized in the NICU by way of a scoping review. Methodology. An electronic search was conducted in the databases of CINAHL, PubMed, Medline, Web of Science, GeryLit.org and Grey Source Index. This scoping review follows the JBI guidelines for scoping reviews. Results. A total of 78 articles were included in the scoping review which identified key elements of neonatal prolonged pain such as definitions (n=25), indicators (n=37), contexts (n=47), pain scales (n=49), consequences (n=29) and possible interventions (n=21) for prolonged pain management. The contexts of care were identified as being more indicative of prolonged pain and should guide pain evaluation and management. Conclusion. This master’s thesis contributes to the foundation of growing knowledge in neonatal prolonged pain and sheds light on the ambiguity that currently exists on this topic in the scientific literature and informs nursing prolonged pain management in NICU with the ultimate goal of improving developmental outcomes of premature neonates.

Preterm birth (< 37 weeks gestation) is a major health burden for affected children. Although the risk of health problems increases as the gestational age decreases, research in the last decades has revealed that even late preterm infants born at 34-36 weeks gestational age have higher mortality and morbidity than term infants. Because late preterm infants constitute three fourths of preterm infants, they are important from both public health and health policy perspectives. This doctoral thesis sought to answer important knowledge gaps in health service utilization of late preterm infants via three studies. Study A, a systematic review and meta-analysis comparing health service utilizations of late preterm infants with those of term infants, found that late preterm infants had increased hospitalization compared with term infants that persisted from the neonatal period through adolescence. Study B is a cohort study evaluating the re-admissions and emergency department visits by late preterm and term singletons and twins for the first 5 years after birth. Study B demonstrated that late preterm infants had higher re-admission rates than term infants although differences in twins were less pronounced than in singletons. Study C is a population-based cohort study with cost analyses assessing the health care costs and resource utilization related to three different discharge timings of late preterm and term singletons: early (< 48 hours), late (48-71 hours), and very-late (72-95 hours) discharge after birth. Study C found that early discharge was not associated with the reduction of health care cost in late preterm infants, and instead was associated with an increase in the cost in term infants over the first year after birth. These findings are useful for parents, care providers, health policy makers, and guideline developers to provide optimal care for late preterm infants. / Thesis / Doctor of Philosophy (PhD)

Le niveau d’hémoglobine (Hb) d’un nouveau-né diminue dans les premiers mois de vie. Cette anémie dite physiologique est plus sévère chez les nourrissons admis aux soins intensifs néonataux (SIN), et ceux-ci nécessitent souvent une transfusion sanguine. En néonatalogie, les indications de transfuser sont controversées et les pratiques transfusionnelles sont très variables. Pour mieux comprendre ces pratiques, nous avons mené l’étude prospective «Epidemiology and determinants of red blood cells transfusion in a neonatal intensive care unit: a cohort study». 13.4% des patients consécutifs admis aux SIN pendant l’étude ont reçu au moins une transfusion sanguine. Les prématurés nés à moins de 28 semaines d’âge gestationnel ont reçu la majorité des transfusions (62.2%) mais les nourrissons à terme admis aux SIN sont aussi fréquemment transfusés (4.9% des transfusions). Les principales justifications évoquées par les cliniciens prescrivant des transfusions sont un niveau bas d’Hb, la maladie de base et le désir d’améliorer l’oxygénation des organes. Notre étude a confirmé une grande variabilité du seuil d’Hb justifiant une transfusion, s’étendant de 62 à 137 g/L. Le syndrome de défaillance multiviscérale (SDMV), défini par l’observation simultanée d’au moins deux dysfonctions d’organes, est un facteur important de mortalité-morbidité chez les enfants traités en soins intensifs pédiatriques. L’association entre SDMV et transfusions est bien décrite dans cette population. Deux listes de critères diagnostiques du SDMV pédiatrique sont utilisées dans la littérature médicale : celles de Proulx et de Goldstein. Nous avons entrepris l’étude de cohorte prospective «Multiple organ dysfunction syndrome in critically ill children : clinical value of two lists of diagnostic criteria» dans le but de valider et de comparer leur valeur diagnostique respective. Nos résultats ont démontré que l’épidémiologie du SDMV varie selon la définition utilisée : l’incidence était de 21.4% vs. 37.3% selon les critères de Proulx et de Goldstein respectivement. Les deux listes de critères diagnostiques ont une bonne reproductibilité inter- et intra-observateur; celle de Proulx est cependant associée à une plus haute mortalité à 90 jours (17.8% vs. 11.5%, p = 0.038). Le SDMV a été décrit chez les nouveau-nés en SIN en utilisant le NEOMOD, un score adapté à cette population. Avec une meilleure caractérisation, le SDMV deviendrait un critère de jugement intéressant pour les essais cliniques randomisés en médecine transfusionnelle en néonatologie. / In the first few months of life, the level of hemoglobin (Hb) in the newborn normally decreases. This physiological anemia is more severe in neonates admitted to a neonatal intensive care unit (NICU), who frequently require a red blood cells (RBC) transfusion. In neonatal medicine, the indications for transfusion are controversial and practices are highly variable. To better understand those practices, we conducted the prospective study: «Epidemiology and determinants of red blood cells transfusion in a neonatal intensive care unit: a cohort study». Among the patients consecutively admitted to NICU during the study period, 13.4% received at least one RBC transfusion. Although premature babies born at less than 28 weeks gestation received the majority of transfusions (62.2%), term neonates admitted to NICU were also frequently transfused (4.9% of transfusions). The main justifications for giving a RBC transfusion were: low Hb level, underlying illness and to improve oxygen delivery. We also observed a wide range of Hb thresholds that triggered a decision to transfuse (from 62 to 137 g/L). The multiple organ dysfunction syndrome (MODS), which is defined as the simultaneous dysfunction of at least two organs or systems, is highly associated with mortality and morbidity in critically ill children. The association between MODS and transfusions is also well described in this population. Two sets of criteria of pediatric MODS are currently used in the medical literature: one by Proulx, and another by Goldstein. We did the prospective cohort study «Multiple organ dysfunction syndrome in critically ill children : clinical value of two lists of diagnostic criteria» to validate and compare the diagnostic value of those two definitions of MODS. We observed that the epidemiology of MODS varies according to which list of criteria is used: the incidence was 21.4% vs. 37.3% with Proulx and Goldstein criteria, respectively. Both sets of criteria have a good inter- and intra-rater reproducibility. The diagnostic of MODS according to Proulx criteria is associated with higher 90-days mortality (17.8% vs. 11.5%, p = 0.038). MODS is also described in neonates, using a score adapted to this population, the NEOMOD. Neonatal MODS represents an interesting outcome measure in clinical trials in neonatal transfusion medicine. However, prior to that, it needs to be better characterized.

Le potentiel acoustique évoqué (PAE) est influencé par l’âge dans de nombreuses espèces. Chez l’homme, l’augmentation de la fréquence de stimulation améliore la détection des anomalies du tronc cérébral. Son utilisation chez le poulain demeure anecdotique. Les buts de cette étude étaient: 1) de déterminer les valeurs de référence du PAE pour 3 différents protocoles de stimulation (11.33 Hz/70 dBNHL; 11.33 Hz/90 dBNHL; 90 Hz/70 dBNHL); 2) d’évaluer les effets de l’âge et de la fréquence de répétition de la stimulation acoustique sur les tracés du PAE chez le poulain de moins de 6 mois; 3) de comparer les données obtenues chez les poulains normaux à celles recueillies chez des poulains présentant des troubles neurologiques. Trente-neuf poulains normaux et 16 poulains avec des déficits neurologiques ont été inclus dans l’étude. Aucun effet de l’âge n’a été mis en évidence (p> 0,005). Aucune différence significative n’a été mise en évidence lorsque les latences absolues et relatives des poulains neurologiques ont été comparées à celles des poulains normaux (p>0,005). L’augmentation de la fréquence de stimulation acoustique n’a pas amélioré la détection d’anomalies sur les tracés de PAE chez les poulains neurologiques. Bien que toutes leurs valeurs de latences absolues et relatives soient demeurées à l’intérieur des valeurs de référence, 78,6% des poulains avec un déficit neurologique présentaient une asymétrie entre les tracés des deux oreilles. Cela démontre une différence de conduction de l’influx nerveux entre le côté droit et le côté gauche du tronc cérébral chez ces sujets. En conclusion, nous présentons ici les valeurs de référence du PAE chez le poulain de moins de 6 mois pour 3 protocoles de stimulation différents. D’autres études seraient nécessaire afin de déterminer si l’utilisation d’une fréquence de stimulation acoustique plus élevée est utile dans la détection d’anomalies du PAE chez les poulains souffrant de troubles neurologiques. La majorité des poulains avec des déficits neurologiques ont présenté des anomalies du PAE ce qui valide son utilisation pour le diagnostic de troubles neurologiques chez le poulain de moins de 6 mois. / Age and rate of acoustic stimulation are reported to affect peak latencies in brainstem auditory evoked responses (BAER) in different species. In foals, its use remains quite anecdotic but, as in humans and dogs, could be useful in the early diagnosis of central nervous system (CNS) disorders. The goals of this study were to 1) establish the reference values for BAER in foals using 3 different stimulation protocols (11.33 Hz/70 dBNHL; 11.33 Hz/90 dBNHL; 90 Hz/70 dBNHL), 2) evaluate the effects of age and rate of stimulation on BAER traces in foals up to 6 months old, and 3) compare these data with BAER obtained from foals with CNS disorders. Thirty-nine neurologically normal foals and 16 foals with neurological deficits were included in this study. No effects of age were observed in normal foals (p> 0.005). No significant differences were observed for latencies and interpeak latencies (IPL) when neurological foals were compared to normal foals (p> 0.05). Increasing the stimulation rate did not improve detection of CNS disorders. All neurologically abnormal foals had latencies and IPL within reference values. However, 78.6% of them had an asymmetry in their traces, reflecting a difference in conduction time between the left and right size of the brainstem. In conclusion, we provide reference values of BAER for foals up to 6 months using 3 different protocols. Further investigations are needed to conclude on the use of an increased rate of acoustic stimulation in foals. Most importantly, most foals with neurological deficits had also an abnormal BAER. This proves BAER is useful is the early diagnosis of neurological disorders in foals