Tear film osmolarity variation between weeks in healthy and dry eye disease subjects / Variação semanal da osmolaridade do filme lacrimal em indivíduos saudáveis e com síndrome do olho seco

ABSTRACT Purpose: The possible variability in diagnostic test results is a statistical feature of dry eye disease patients. The clinician should consider tear film variations over time since the timing of tear film measurements is important for proper diagnosis. The purpose of the present study was to analyze the inter-week variation of osmolarity measurement in healthy and dry eye disease participants. Methods: Based on the Dry Eye Workshop II (DEWS-II) diagnostic methodology report criteria, a battery of tests (Ocular Surface Disease Index [OSDI] questionnaire, breakup time, and corneal staining) was administered to rule out the presence of dry eye disease. A total of 40 qualified volunteers were recruited into two groups: with only 20 healthy and 20 dry eye disease participants. The inter-week variation of osmolarity in the two groups was measured using a TearLab osmometer in two sessions one-week apart. The differences between the results were calculated. Results: There were no significant differences in osmolarity between the two sessions for either the healthy (paired t-test; p=0.085) or dry eye disease (paired t-test; p=0.093) participants. Moreover, there was no significant correlation between the means and differences in either session on healthy (Pearson correlation: r=0.020; p=0.935) or dry eye disease (Pearson correlation: r=-0.022; p=0.928) participants. In session 1, there was a significant difference in osmolarity values between groups (unpaired t-test; p=0.001), but no difference was found in session 2 (unpaired t-test; p=0.292). Conclusions: The present study discovered no inter-week variation in the tear film osmolarity of healthy and dry eye disease participants classified based on the DEWS-II criteria.

RESUMO Objetivo: A possível variabilidade nos resultados de testes diagnósticos é uma característica estatística dos pacientes com síndrome do olho seco. O médico deve considerar as variações do filme lacrimal ao longo do tempo, pois o momento em que o filme lacrimal é medido pode ser crítico para o diagnóstico adequado. O objetivo deste estudo foi analisar a variação semanal da osmolaridade do filme lacrimal em participantes saudáveis e em outros com síndrome do olho seco. Métodos: Com base nos critérios da metodologia de diagnóstico do relatório da Dry Eye Workshop II (DEWSII), foi aplicada uma bateria de testes (questionário do índice de doença da superfície ocular [OSDI], tempo de ruptura do filme lacrimal e coloração da córnea) para descartar a presença de síndrome do olho seco. Um total de 40 voluntários qualificados foi recrutado e distribuído em dois grupos de 20 participantes saudáveis e 20 participantes com síndrome do olho seco. A variação da osmolaridade entre semanas foi medida com um osmômetro TearLab em duas sessões com uma semana de intervalo nos dois grupos. As diferenças entre os resultados foram então calculadas. Resultados: Não foram encontradas diferenças significativas na osmolaridade entre as medidas obtidas nas duas sessões, nem no grupo de participantes saudáveis (teste de t pareado; p=0,085), nem no de participantes com síndrome do olho seco (teste de t pareado; p=0,093). Não foi detectada nenhuma correlação significativa entre as médias e diferenças entre as duas sessões entre participantes saudáveis (correlação de Pearson: r=0,020, p=0,935) e aqueles com síndrome do olho seco (correlação Pearson: r=-0,022, p=0,928). Foi encontrada uma diferença significativa nos valores de osmolaridade entre os dois grupos na primeira sessão (teste de t não pareado; p=0,001), mas nenhuma diferença foi encontrada na segunda sessão (teste de t não pareado; p=0,292). Conclusões: O presente estudo não encontrou variação entre semanas consecutivas na osmolaridade do filme lacrimal em participantes saudáveis e com síndrome do olho seco, classificados com base nos critérios do DEWSII.

Hipertensão ocular recorrente durante hemodiálise em paciente portador de glaucoma / Recurrent intraocular hypertension during hemodialysis in glaucoma patient

RESUMO A hipertensão ocular aguda durante a hemodiálise constitui evento raro e pode ser causa relevante de interrupção do tratamento dialítico devido à dor. Relata-se o caso de um paciente de 70 anos de idade, do sexo masculino, que apresentou quadros recorrentes de intensa dor ocular unilateral durante sessões dialíticas devido ao aumento de pressão intraocular. O paciente era portador de grave diminuição da acuidade visual no olho direito devido a glaucoma neovascular, controlado com medicação hipotensora tópica. Uma hora após o início da sessão dialítica, apresentou dor excruciante no olho direito, sendo necessário interromper o tratamento por diversas vezes. A dor somente era amenizada com uso de opioides por via endovenosa ou após cerca de 6 horas do procedimento. Injeção intraocular de drogas antiangiogênicas e acetazolamida por via oral, assim como tratamentos tradicionais para quadros agudos de hipertensão intraocular, como uso de hipotensor tópico e medicamentos hiperosmolares, foram insuficientes para o controle da dor. O problema se resolveu com ciclofotocoagulação transescleral realizada com laser diodo, com redução da pressão intraocular basal e controle da dor, o que permitiu a realização de sessões completas de hemodiálise. A base fisiopatológica desse evento incomum e suas opções terapêuticas são discutidas aqui.

ABSTRACT Acute ocular hypertension during hemodialysis is a rare event and may lead to interruption of dialytic therapy due to pain. A case of a 70-year-old male patient is reported, who presented recurrent intense unilateral ocular pain episodes during dialysis sessions for increased intraocular pressure. The patient presented with severely decreased visual acuity in the right eye due to neovascular glaucoma, which was controlled with topical hypotensive medication. One hour after initiating dialysis, he presented an excruciating pain on the right eye, which required interruption of treatment several times. Pain relief was possible only with intravenous opioids, or approximately 6 hours after dialysis. Intraocular injection of antiangiogenic drugs and per oris acetazolamide, as well as other traditional treatments for acute episodes of intraocular hypertension, such as topical antihypertensive agents and hyperosmotic medications, were not sufficient to control pain. The problem was solved with transscleral diode laser cyclophotocoagulation, which reduced baseline intraocular pressure and controlled pain, enabling complete hemodialysis sessions. The pathophysiological aspects and therapeutic options of this unusual condition are discussed.

Effects of the ice popsicle on vasopressin, osmolality, thirst intensity, and thirst discomfort / Efectos del picolé de hielo sobre vasopresina, osmolaridad, intensidad y malestar de la sed / Efeitos do picolé de gelo sobre vasopressina, osmolaridade, intensidade e desconforto da sede

ABSTRACT Objective: To analyze the effects of the ice popsicle on vasopressin, osmolality, thirst intensity, and thirst discomfort. Method: This is a quasi-experimental, pre- and post-test study conducted in a laboratory. The sample consisted of nine healthy male volunteers, who received 2% hypertonic saline solution. Results: Popsicle intake did not result in a statistically significant reduction in vasopressin levels (F=0.876 and p=0.428). However, there was a reduction in the hormonal physiological profile of vasopressin from 7.1 pg/ml to 5.8 pg/ml after the first two interventions. Osmolality concentration changed from 270.65 to 286.51 mOsm/kg, with no statistical difference (F=2.207; p=0.09). Ice popsicles significantly reduced thirst intensity (F=10.00; p=0.001) and thirst discomfort (F=10.528; p <0.001). Conclusion: There was a reduction in thirst intensity and discomfort after the use of the 20 ml ice popsicle. There was no statistical difference for vasopressin and osmolality. However, there was a reduction in the hormonal physiological profile of vasopressin during 30 minutes of intervention.

RESUMEN Objetivo: Evaluar los efectos del picolé de hielo sobre el perfil hormonal de la vasopresina, la osmolaridad, y la intensidad y el malestar de la sed. Método: Estudio casi-experimental pre- y pos-test, realizado en laboratorio. Nueve varones voluntarios sanos recibieron solución salina endovenosa al 2% y un picolé de hielo de 20 ml cada 15 minutos. Resultados: Ingerir el picolé no derivó en una caída estadísticamente significativa del nivel de vasopresina (F=0,876 y p=0,428). Entretanto, se registró una reducción en el perfil hormonal de la vasopresina de 7,1 pg/ml a 5,8 pg/ml después de las dos intervenciones. La osmolaridad plasmática se modificó de 270,65 a 286,51 mOsm/kg sin diferencia estadística (F=2,207; p=0,09). Se registraron reducciones en la intensidad (F=10,00 y p= 0,001) y en el malestar de la sed (F= 10,528; p<0,001). Conclusión: Se registraron reducciones en la intensidad y el malestar de la sed después de la intervención. No hubo diferencia estadística para la vasopresina y la osmolaridad. De esta manera, se observa la reducción en el perfil fisiológico de la vasopresina durante los 30 minutos de la intervención.

RESUMO Objetivo: Avaliar efeitos do picolé de gelo sobre perfil hormonal de vasopressina, osmolaridade, intensidade e desconforto da sede. Método: Quase-experimental, pré e pós-teste, realizado em laboratório. Nove voluntários saudáveis receberam solução salina endovenosa 2% e um picolé de gelo 20 ml a cada 15 minutos. As variáveis foram coletadas em cinco momentos. Resultados: Ingestão do picolé não resultou queda estatisticamente significativa da vasopressina (F = 0,876 e p = 0,428). Houve redução no perfil hormonal da vasopressina de 7,1 pg/ml para 5,8 pg/ml após duas intervenções. Osmolaridade plasmática alterou de 270,65 para 286,51 mOsm/kg, sem diferença estatística (F=2,207; p= 0,09). Houve redução da intensidade (F=10,00 e p= 0,001) e desconforto da sede (F=10,528; p < 0,001). Conclusão: Houve redução na intensidade e desconforto da sede. Não houve diferença estatística para vasopressina e osmolaridade. Observou-se redução no perfil fisiológico da vasopressina durante 30 minutos de intervenção.

Inter-eye osmolarity differences in patients with symptomatic and non-symptomatic dry eyes / Diferenças de osmolaridade entre olhos de pacientes com olhos secos sintomáticos e não sintomáticos

ABSTRACT Purpose: To analyze whether inter-eye osmo larity differences were related to dry eye symptomatology. Methods: A total of 135 participants were randomly recruited from those who visited in the Optometry Clinic of the Optometry Faculty (Universidade de Santiago de Compostela). In a single scheduled session after the recruitment, Ocular Surface Disease Index was filled out following the standard instructions and TearLab measurements were made in both the participants' eyes (10-15 min lapse). Osmolarity values were compared between the right and left eyes and the absolute inter-ocular difference (-OD-OS-) correlated with the Ocular Surface Disease Index score for the whole sample. Based on the Ocular Surface Disease Index score, the sample was divided into four symptomatic subgroups, and differences in the -OD-OS- values were calculated. Results: The whole sample showed a statistically significant inter-eye osmolarity difference (p=0.025; -OD-OS- = 9.2 ± 9.3 mOsm/l) and the correlation between Ocular Surface Disease Index and -OD-OS- (r=0.369; p<0.001). A statistically significant difference was found in the -OD-OS- value between symptomatic subgroups (Kruskal-Wallis, p=0.003). Mann-Whitney U test showed a significant difference between asymptomatic vs. moderate (p=0.006) vs. severe symp tomatic patients (p=0.001) and between mild vs. severe symptomatic patients (p=0.045), whereas no difference on -OD-OS- was found between participants with contiguous symptomatic subgroups (all p³0.174). Conclusion: Tear film inter-eye osmolarity differences are significantly higher in severe dry eye disease symptoms.

RESUMO Objetivo: Analisar se as diferenças entre osmolaridade entre os olhos foram relacionadas à sintomatologia do olho seco. Métodos: Um total de 135 participantes foram recrutados aleatoriamente entre os indivíduos da Clínica de Optometria da Faculdade de Optometria (Universidade de Santiago de Compostela). Em uma única sessão agendada após o recrutamento, o Índice de Doenças da Superfície Ocular foi preenchido seguindo as instruções padrão e as mensurações do TearLab foram feitas em ambos os olhos dos participantes (lapso de 10 a 15 min). Os valores de osmolaridade foram com parados entre os olhos direito e o esquerdo e a diferença absoluta ocular (-OD-OS-) correlacionada com a pontuação do Índice de Doença da Superfície Ocular para toda a amostra. Com base na pontuação do Índice de Doença da Superfície Ocular, a amostra foi dividida em quatro subgrupos sintomáticos, e as diferenças nos -OD-OS- os valores foram calcula dos. Resultados: A amostra total mostrou uma diferença de osmolarida de entre os olhos estatisticamente significativa (p=0,025; -OD-OS- = 9,2 ± 9,3 mOsm/l) e a correlação entre o Índice de Doença da Superfície Ocular e -OD-OS- (r=0,369; p<0,001). Diferença estatisticamente significativa foi encontrada no valor -OD-OS- entre os subgrupos sintomáticos (Kruskal-Wallis, p=0,003). O teste U de Mann-Whitney mostrou uma diferença significativa entre pacientes assintomáticos versus moderados (p=0,006) versus sintomáticos graves (p=0,001) e entre pacientes sinto máticos leves e graves (p=0,045), enquanto que nenhuma di ferença de -OD-OS- foi encontrada entre os participantes de subgrupos sintomáticos contíguos (todos p³0,174). Conclusão: As diferenças entre osmolaridade inter-ocular do filme lacrimal são significativamente maiores nos sintomas graves da doença do olho seco.

A simple predictive factor for mortality in fontan surgery: serum hypo-osmolality

Abstract Objective: Close follow-up is important after the Fontan procedure, which is a palliative surgical method for a single ventricle. In this period, serum osmolality is an important parameter with the advantages of easy to obtain and poor outcome prediction. Methods: Patients who had undergone Fontan operation between May 2011 and February 2017 were retrospectively evaluated. Patients were divided into three groups based on their serum osmolality values: hypoosmolar (Group 1), isosmolar (Group 2), and hyperosmolar (Group 3). Demographics, clinical information and postoperative data of the groups were compared. Results: Forty-three patients had undergone extracardiac Fontan operation in the study period. There were 8, 19 and 16 patients in Groups 1, 2 and 3, respectively. Among the three groups, postoperative intubation and length of hospital stay, prolonged pleural effusion, need for inotropic support and mortality were statistically significantly higher in Group 1. Conclusion: After the Fontan procedure, one of the determinants of cardiac output might be affected by serum osmolality. Decreased serum osmolality might be associated with poor prognosis after Fontan procedure. Serum osmolality monitoring may be beneficial to improve postoperative outcomes in these patients.

Ocular surface evaluation in pediatric Hashimoto's thyroiditis without thyroid-associated ophthalmopathy / Avaliação da superfície ocular na tireoidite de Hashimoto pediátrica sem oftalmopatia associada à tireoide

ABSTRACT Purpose: We aimed to assess ocular surface characteristics in children with Hashimoto's thyroiditis without thyroid-associated ophthalmopathy and compare the results with those of healthy children. Methods: Twenty-two children with Hashimoto's thyroiditis (Group 1) and 20 healthy children without any ocular and/or systemic disorder (Group 2) were enrolled in the study. Ocular Surface Disease Index questionnaire, tear film osmolarity measurement (TearLab Osmolarity System, San Diego, CA, USA), Schirmer and tear film breakup time tests, meibography, and conjunctival brush cytology were performed and compared the results between the groups. Results: The study group included 19 girls and 3 boys in Group 1 and 12 girls and 8 boys in Group 2 (p=0.081). Thyroid-associated ophthalmopathy was not identified in any of the patients. Mean tear film osmolarity was 310.23 ± 11.98 mOsm/l in Group 1 and 313.60 ± 15.03 mOsm/l in Group 2 (p=0.424). Mean Schirmer test score was lower in Group 1 (14.91 ± 6.27) compared with Group 2 (23.60 ± 5.63) (p=0.001). Mean tear film breakup time was lower in Group 1 (11.78 ± 4.07) compared with Group 2 (15.1 ± 1.6) (p=0.013). Moreover, mean meibomian gland area loss was 25.01% ± 10.04% in Group 1 and 16.54% ± 6.02% in Group 2 (p=0.002). Conjunctival cytologic analysis in Group 1 revealed grade 0 changes in 6 patients (27.3%), grade 1 changes in 14 patients (63.6%), and grade 2 changes in 2 patients (9.1%), whereas 18 patients (90%) had grade 0 changes and 2 patients (10%) had grade 1 changes (p=0.001) in Group 2. Conclusions: The study demonstrates several ocular surface changes in children with Hashimoto's thyroiditis. These findings may indicate a tendency for dry eye in pediatric Hashimoto's thyroiditis patients without clinical evidence of thyroid-associated ophthalmopathy.

RESUMO Objetivo: Avaliar as características da superfície ocular em crianças com tireoidite de Hashimoto sem oftalmopatia associada à tireoide e comparar os resultados com aqueles de crianças saudáveis. Métodos: Vinte e duas crianças com tireoidite de Hashimoto (Grupo 1) e 20 crianças saudáveis sem qualquer distúrbio ocular e/ou sistêmico (Grupo 2) participaram do estudo. Utilizou-se o questionário Índice da Doença da Superfície Ocular, medida de osmolaridade do filme lacrimal (Tearlab Osmolarity System, San Diego, CA, EUA), teste de Schirmer e tempo de ruptura do filme lacrimal, meibografia e citologia do raspado conjuntival e comparação dos resultados entre os grupos. Resultados: O grupo de estudo incluiu 19 meninas e 3 meninos no Grupo 1 e 12 meninas e 8 meninos no Grupo 2 (p=0,081). A oftalmopatia associada à tireoide não foi identificada em nenhum dos pacientes. A média da osmolari­dade do filme lacrimal foi 310,23 ± 11,98 mOsm/l no Grupo 1 e 313,60 ± 15,03 mOsm/l no Grupo 2 (p=0,424). A média do escore do teste de Schirmer foi menor no Grupo 1 (14,91 ± 6,27) do que no Grupo 2 (23,60 ± 5,63) (p=0,001). A média do tempo de ruptura do filme lacrimal foi menor no Grupo 1 (11,78 ± 4,07) em comparação com o Grupo 2 (15,1 ± 1,6) (p=0,013). Além disso, a média da perda de área da glândula meibomiana foi 25,01% ± 10,04% no Grupo 1 e 16,54% ± 6,02% no Grupo 2 (p=0,002). A análise da citologia conjuntival no Grupo 1 revelou alterações de grau 0 em 6 pacientes (27,3%), alterações de grau 1 em 14 pacientes (63,6%) e alterações de grau 2 em 2 pacientes (9,1%), enquanto 18 pacientes (90%) com alteração de grau 0 e 2 pacientes (10%) com alteração de grau 1 (p=0,001) no Grupo 2. Conclusões: O estudo demonstra várias alterações da superfície ocular em crianças com tireoidite de Hashimoto. Esses achados podem indicar uma tendência para olho seco em pacientes pediátricos com tireoidite de Hashimoto, sem evidências clínicas de oftalmopatia associada à tireoide.

Osmolality analysis of human milk and an infant formula with modified viscosity for use in infants with dysphagia / Análise da osmolalidade do leite humano e da fórmula infantil com a viscosidade modificada para uso em lactentes com disfagia

ABSTRACT Purpose: to evaluate the effects of a thickening agent on the osmolality of human milk and on an infant formula, with respect to concentration and time. Methods: six trials were performed to evaluate the osmolality of a natural and thickened infant formula, raw human milk, and pasteurized human milk. Rice cereal was used as a thickening agent (at concentrations of 2%, 3%, 5%, and 7%). Osmolality was measured using the Advanced Micro Osmometer Model 3300 after sample preparation periods of 0-60 minutes. Statistical evaluations were performed using ANOVA. Results: pasteurized human milk exhibited time- and concentration-dependent variation in osmolality. The osmolality of raw human milk differed among time points and between the samples with 5% and 7%, when compared to the non-thickened milk. The infant formula did not show differences in osmolality with respect to time. At time zero, there were differences in osmolality between the infant formula samples with 2%, 3%, and 5% thickener. At other time points, there were differences in osmolality between the sample with a 5% thickener and the non-thickened formula. Conclusion: the osmolality of diets varied over time and according to the concentration of thickener in human milk and the infant formula. However, the observed variation remained within the recommended parameters, indicating that rice cereal is a safe thickener for the feeding of infants presented with mild or moderate oropharyngeal dysphagia.

RESUMO Objetivo: avaliar o efeito do agente espessante na osmolalidade do leite humano e da fórmula infantil em relação às concentrações e ao efeito do tempo. Métodos: foram realizados 6 ensaios para avaliar a osmolalidade, ao natural e com espessamento, da fórmula infantil, leite humano ordenhado cru e pasteurizado. O cereal de arroz foi usado como agente espessante (nas concentrações de 2%, 3%, 5% e 7%). A osmolalidade foi aferida pelo The Advanced TM Micro Osmometer Model 3300 após a preparação das amostras por um período de 0-60 minutos. As diferenças significantes foram avaliadas por meio de Anova. Resultados: observou-se variação da osmolalidade no leite humano pasteurizado nos tempos observados e nas concentrações. O leite humano cru apresentou variação nos tempos e nas concentrações 5 e 7%, quando comparado ao leite não espessado. A fórmula infantil não mostrou diferenças na osmolalidade com relação ao tempo. No tempo zero, apresentou variações entre as concentrações de 2, 3 e 5%. Nos demais tempos, houve diferença na osmolalidade entre as amostras com concentração de 5% e a fórmula não espessada. Conclusão: a osmolalidade das dietas analisadas variou conforme o tempo e as concentrações para o leite humano e a formula infantil. No entanto, estas variações se mantiveram dentro dos parâmetros preconizados, indicando que o cereal de arroz é um espessante seguro para a alimentação de lactentes com disfagia orofaríngea leve ou moderada.

Serum markers and development of delayed neuropsychological sequelae after acute carbon monoxide poisoning: anion gap, lactate, osmolarity, S100B protein, and interleukin-6

OBJECTIVE: Reliable biomarkers of delayed neuropsychological sequelae (DNS) after acute carbon monoxide (CO) poisoning are lacking. This study investigated the associations between potential serum markers and the development of DNS after acute CO poisoning. METHODS: Retrospective chart reviews were conducted for patients diagnosed with acute CO poisoning during a 28-month period. The patients were divided into two groups according to the presence or absence of having developed DNS. Multivariate analysis was performed to identify predictors of DNS after CO poisoning. RESULTS: Of a total of 102 patients, 10 (9.8%) developed DNS. The levels of serum osmolarity, S100B protein, and serum lactate, as well as serum anion gap, were statistically significant in univariate analysis. Multiple logistic regression analysis showed that anion gap (adjusted odds ratio [AOR], 1.36; 95% confidence interval [CI], 1.11 to 1.88), serum lactate level (AOR, 1.74; 95% CI, 1.26 to 2.75), and serum S100B protein level ([AOR, 7.02×10⁵; 95% CI, 4.56×10² to 9.00×10¹⁰] in model 1, [AOR, 3.69×10⁵; 95% CI, 2.49×10² to 2.71×10¹¹] in model 2) were independently associated with DNS development. CONCLUSION: Based on our preliminary results, serum lactate level, serum anion gap, and serum S100B protein level in the emergency department could be informative predictors of DNS development in patients with acute CO poisoning. These markers might have the potential to improve early recognition of DNS in patients with acute CO poisoning.

The measurement of serum osmolality and its application to clinical practice and laboratory: literature review / A medida da osmolalidade sérica e sua aplicação na prática clínica e laboratorial: revisão da literatura

ABSTRACT Introduction: Serum osmolality is an essential laboratory parameter to understand several clinical disorders such as electrolyte disturbances, exogenous intoxication and hydration status. Objective: This study aims to update knowledge about the osmolality examination through research papers published to date. Materials and methods: The survey was conducted on PubMed database. It highlights main concepts, both historical and physiological aspects, and the clinical applications of the serum osmolality test. In addition, an extensive survey of formulas for the serum osmolality calculation was conducted. Discussion: The measurement of serum osmolality is relevant in changes in intracellular and extracellular balance, as a trusted and valuable indicator of solute concentration in the blood. The mathematical equations for serum osmolality calculation acquire relevance in health services where serum is not available, and situations in which calculation of the osmolal gap is necessary, but the variability of the formulas is a significant bias. Conclusion: The measurement of serum osmolality is useful in cases of dehydration, sodium and potassium disorders, glucose alteration, exogenous poisoning, adrenal insufficiency, neurological injury, physical exercise and others.

RESUMO Introdução: A osmolalidade sérica constitui um parâmetro laboratorial importante para compreensão de diversas desordens clínicas, como os distúrbios eletrolíticos, as intoxicações exógenas e o status de hidratação. Objetivo: Este trabalho visa atualizar os conhecimentos acerca do exame de osmolalidade por meio da pesquisa de artigos científicos publicados até a presente data. Materiais e métodos: A pesquisa foi realizada no banco de dados do PubMed. Este artigo de atualização aborda os principais conceitos, aspectos históricos, aspectos fisiológicos e aplicações clínicas do exame de osmolalidade sérica. Foi também realizado um levantamento das diferentes fórmulas propostas para o cálculo da osmolalidade sérica. Discussão: A medida da osmolalidade sérica é pertinente nas alterações do equilíbrio intra e extracelular, sendo um bom indicador para avaliar as concentrações de solutos no sangue. As fórmulas matemáticas para o cálculo da osmolalidade sérica são úteis quando a medida laboratorial não está disponível, bem como nas situações em que o cálculo do gap osmolal se faz necessário, mas a variabilidade das fórmulas é um viés significativo. Conclusão: A medida da osmolalidade sérica é útil na avaliação de diversas condições clínicas, como na desidratação, nos distúrbios dos íons sódio e potássio, nas disglicemias, nas intoxicações exógenas, na insuficiência adrenal, nas lesões neurológicas, nos exercícios físicos, entre outras.

Osmolality and pH in handmade enteral diets used in domiciliary enteral nutritional therapy

Patients who need prolonged domiciliary enteral nutritional therapy may benefit from handmade diets. However, the preparation of such diets might cause insecurity with regard to their nutritional composition and physical-chemical properties. Current study analyzes the osmolality and Hydrogen-Ion concentration (pH) on handmade enteral diets. To this purpose, six formulas and two juices, prescribed on discharge from hospital, were analyzed physically and chemically. Osmolality and pH were respectively determined by cryoscopy and potentiometry. Most formulations were classified as isosmolar (with less than 400 mOsm/kg solvent), and only one was classified as slightly hyperosmolar, with rates ranging from 356.7 to 403.5 mOsm/kg solvent. On average, the standard formula presented higher osmolality than similar ones prepared for hyperglycemia. Among the juices, only one registered hyperosmolar concentration of 595.54 mOsm/kg solvent. All formulas presented pH rates classified as low acidity, ranging between 6.1 and 6.6, while the two juices had the lowest results, 4.73 and 4.66 each. The blend of ingredients used in handmade formulas and juices studied presented acceptable osmolality and pH rates for a safe administration and absence of gastrointestinal complications. Data showed here are consistent with an appropriate and healthy diet and contributed towards success in domiciliary enteral nutritional therapy.

Tear osmolarity and tear function assessment in patients with polycystic ovary syndrome / Avaliação da osmolaridade lacrimal e da função lacrimal em pacientes com síndrome dos ovários policísticos

ABSTRACT Purpose: Polycystic ovary syndrome (PCOS) is an endocrine disease characterized by chronic anovulation and hyperandrogenism. Hormonal changes can affect tear function. This study evaluates tear function and impact of hyperandrogenism on it in PCOS patients. Methods: Fifty patients with PCOS and thirty control volunteers were examined for tear break-up time, Schirmer-I and tear osmolarity. Also, serum levels of total testosterone, FSH, LH and AMH were determined in venous blood samples in the early follicular phase. PCOS patients were divided into two groups by plasma total testosterone level: Group A with normal (≤0.513 ng/ml;n=27), Group B with higher hormone level (>0.513 ng/ml;n=23). Healthy control group indicated as Group C (n=30). Results: LH, total testosterone levels were higher in the PCOS group than in the control group (p=0.012; p=0.025). Mean values of tear break-up time and Schirmer-I were different between groups and especially Group A and C were near to each other differing from B (p>0.05). Tear osmolarity results were higher in Group B, compared to A and C (p=0.049; p=0.033). No significant difference detected in tear osmolarity value means of Group A and C (p=0.107). AMH levels were higher in Group B, compared to A and C (p=0.002; p=0.001). AMH levels in Group A were higher than that of C (p=0.002). Positive correlation between levels of total testosterone and AMH was detected in all PCOS patients (n=50;Pearson's r=0.579; p<0.001). Conclusion: Tear function can be affected in PCOS patients with hyperandrogenism. Tear osmolarity is the most sensitive and objective assessment method for ocular surface changes in PCOS.

RESUMO Objetivo: A síndrome do ovário policístico (SOP) é uma doença endócrina caracterizada por anovulação crônica e hiperandrogenismo. As alterações hormonais podem afetar a função cardíaca. Este estudo avalia a função lacrimal e o impacto do hiperandrogenismo sobre ela em pacientes com SOP. Métodos: Cinquenta pacientes com SOP e trinta voluntárias de controle foram examinadas para tempo de ruptura lacrimal, Schirmer-I e osmolaridade lacrimal. Além disso, os níveis séricos de testosterona total, FSH, LH e HAM foram determinados em amostras de sangue venoso na fase folicular precoce.As pacientes com SOP foram divididas em dois grupos por nível de testosterona plasmática total: Grupo A com nível normal (≤0.513 ng/ml; n = 27), Grupo B com nível superior de hormônio (> 0,513 ng/ml; n = 23). Grupo de controle saudável indicado como Grupo C (n = 30). Resultados: Os níveis de LH e testosterona total foram maiores no grupo com SOP do que no grupo controle (p = 0,012; p = 0,025). Os valores médios de tempo de ruptura lacrimal e Schirmer-I foram diferentes entre os grupos, e especialmente os Grupos A e C estavam próximos um do outro, diferente do B (p > 0,05). Os resultados de osmolaridade lacrimal foram maiores no Grupo B, em comparação com A e C (p = 0,049; p = 0,033). Não houve diferença significativa detectada em valor médio de osmolaridade lacrimal nos Grupos A e C (p = 0,107). Os níveis de HAM foram maiores no Grupo B, em comparação com A e C (p = 0,002; p = 0,001). Os níveis de AMH no Grupo A foram superiores aos de C (p = 0,002). Uma correlação positiva entre os níveis de testosterona total e AMH foi detectada em todas as pacientes com SOP (n = 50; Pearson's r = 0,579; p < 0,001). Conclusão: a função lacrimal pode ser afetada em pacientes com SOP com hiperandrogenismo. A osmolaridade lacrimal é o método de avaliação mais sensível e objetivo para alterações da superfície ocular em SOP.

A Case of Methanol Poisoning Treated with Continuous Renal Replacement Therapy: The Serial Measurements of Serum Methanol Concentrations in Methanol Poisoning

Methanol poisoning is a medical emergency that requires rapid elimination of the toxin and its metabolites for recovery. The danger of methanol results from the accumulation of its toxic metabolite formic acid. This accumulation may result in the development of metabolic acidosis, visual impairment, and damage to the basal ganglia. Extracorporeal treatment is recommended in severe cases of methanol poisoning with coma, seizure, new vision deficits, metabolic acidosis, high serum anion gap, elevated methanol concentrations or impaired kidney function. Although the serum methanol concentration is helpful in determining the use of extracorporeal treatment, methanol assays are not standard laboratory tests in Korea. Herein, we report a case of methanol poisoning in which the patient's clinical improvement was confirmed using serum and urine methanol levels.

Ajustes Cardiovasculares Induzidos pela Desidratação Crônica nas Fases Iniciais do Período Pós-Natal em Ratos Acordados / Cardiovascular Adjustments Induced by Chronic Dehydration in the Early Stages of PostNatal in Awake Rats

Alterações da osmolaridade do compartimento extracelular podem alterar o volume, o metabolismo e a função celular. Em virtude disso,varias complicações podem ser observadas, dentre elas a hipertensão arterial. Assim, a regulação precisa do volume e da osmolaridade docompartimento extracelular é fundamental para a manutenção das funções normais do organismo e da sobrevivência. O objetivo desse estudofoi avaliar os parâmetros hemodinâmicos através de desidratação induzida por furosemide em ratos jovens não anestesiados. Foram utilizados,ratos Wistar com cinco dias de idade, divididos em dois grupos experimentais, um controle (n=10) e um submetido ao tratamento comFurosemide (10mg/kg de massa corpórea, n=12), administrado três vezes por semana, durante dois meses. Após o tratamento, os animaisforam anestesiados para cateterização com cânulas inseridas na artéria e veia femorais, através de um corte inguinal de um dos lados. Ascânulas foram transpassadas subcutaneamente através do dorso do animal e foram exteriorizadas. Os experimentos foram realizados apósuma recuperação de 48h do procedimento cirúrgico, utilizando um amplificador e um software. Os resultados obtidos demonstraram que nãohouve diferenças nos testes induzidos de ingestão de água durante os 120 minutos analisados, quando comparados o grupo controle e o grupofurosemide, respectivamente. Na análise da pressão arterial méia e frequência cardíaca, não foi observada modificação dos níveis basais. Essepadrão de resposta também foi obtido quando analisado a PAS e PAD. Com esses resultados, concluímos que a depleção do compartimentoextracelular induzido pela administração de furosemide em ratos jovens não é fator determinante para alteração dos parâmetros hemodinâmicosna fase adulta.

Changes in osmolarity of the extracellular compartment may change the volume, metabolism and cellular function. As a result, manycomplications can be observed, among them hypertension. Thus, precise regulation of the volume and osmolality of the extracellularcompartment is critical to maintaining normal body functions and survival. Previous results demonstrated that despite anesthetized ratssubmitted to chronic diuretic treatment showed no change in sensitivity to sodium and water, an increased arterial pressure was observed. Thepresent study aims to assess hemodynamic parameters through furosemide-induced dehydration in anaesthetized young rats. Five days oldWistar rats divided into two groups, a control (n = 10) and a group subjected to subcutaneous treatment with the diuretic Furosemide (10mg/kg of body weight, n = 12) were used. After treatment, the animals were anesthetized for the implantation of the polyethylene tubes, which wereinserted into the artery (for records cardiovascular variables) and femoral vein through a cut inguinal one side (left / right). The cannulaswere transfixed subcutaneously through the back of the animal and were exteriorized. Data were recorded after a 48h recovery of the surgicalprocedure, using an amplifier and software. No differences in induced intake test of water within 120 minutes were observed. With respect tomean arterial pressure and heart rate, no modification on baseline levels were observed (PAM: 99.4 ± 1.9 mmHg, control vs 102.7 ± 1 mmHg,furosemide; FC: 362.5 ± 5.2 bpm, control vs 364.9 ± 7 bpm, furosemide). This response pattern was also obtained for SBP (124.3 ± 6 mmHg,control vs 130 ± 1.6 mmHg, furosemide) and DBP (82.2 ± 1.9 mmHg, control vs 82.1 ± 1 mmHg, furosemide). We concluded that depletionof the extracellular compartment induced by furosemide administration in young rats is not a determining factor to change the hemodynamicparameters in adulthood.

Lacrimal osmolarity and ocular surface in experimental model of dry eye caused by toxicity / Osmolaridade lacrimal e superfície ocular em modelo de olho seco por toxicidade

Purpose: Describe an animal model of dry induced by topical instillation of BAK and evaluate ocular surface biomarkers and histological findings. Methods: Male Wistar rats were used.Topical instillation of 0.2% BAK eyedrops twice a day during 7 days, in the right eye of each animal, while the other eye was taken as control. After 7 days treatment, we performed evaluation of tear film osmolarity, the red phenol thread and ocular surface staining with fluorescein and lissamine green. Afterwards, the animals were sacrificed for tissue extraction and histological evaluation under optical microscopy and H&E staining. Results: Compared with untreated controls, the BAK-group presented tear secretion significantly decreased, increased ocular surface staining by fluorescein and lissamine green and tear film hyperosmolarity (p <0,05). Histological evaluation revealed epithelial thinning and estromal oedema. Conclusions: A toxicity animal model of dry eye induced by topical instillation of benzalkonium chloride, which presents corneal and ocular surface alterations, decreased tear film volume and tear hyperosmolarity as seen in dry eye condition.

Objetivo: Descrever um modelo animal de olho seco induzido pela aplicação tópica de cloreto de benzalcônio (BAC) e avaliar marcadores de integridade da superfície ocular e os achados histológicos. Métodos: Foram utilizados ratos wistar machos adultos. Foi realizada a administração tópica de colírio de BAC 0,2% no olho direito de cada animal duas vezes por dia, durante 7 dias, sendo o olho contralateral tido como controle. Após o tratamento foi realizada a avaliação da osmolaridade do filme lacrimal, o teste de fenol vermelho e a coloração com fluoresceína e lisamina verde. Os animais foram sacrificados e os tecidos extraídos para o estudo histológico da córnea, por microscopia óptica, corada com hematoxilina eosina (H&E). Resultados: Comparados com os controles não tratados o grupo BAC apresentou diminuição significativa na secreção lacrimal, defeitos na integridade epitelial da superfície ocular marcada por corantes vitais, fluoresceína e lisamina verde além do aumento da osmolaridade do filme lacrimal (p < 0,05). À avaliação histológica observou-se diminuição da espessura do epitélio e edema estromal induzidos pela aplicação de BAC. Conclusão: O modelo animal de olho seco por toxicidade induzido pela aplicação tópica de cloreto de benzalcônio apresentou alterações estruturais da córnea e da superfície ocular, diminuição do volume lacrimal e hiperosmolaridade da lágrima características dessa condição.

Diagnostic value of tear hyperosmolarity in dry eye / 中华实验眼科杂志

Background Tear hyperosmosis is considered to be one of the core mechanisms of dry eye.The measurement of tear osmolarity is important in the clinical diagnosis of dry eye.However,relevant study is lack in Chinese population.Objective The aim was to investigate the relation of tear osmolarity and pathogenesis of dry eye and evaluate the diagnosis value of tear hyperosmosis in dry eye.Methods Sixty-one consecutive dry eye patients were enrolled in Affiliated Eye Hospital of Wenzhou Medical University from May to August in 2011,including 30 mild and moderate dry eyes and 31 severe dry eyes,and 30 normal volunteers with matched age and gender were collected simultaneously under the informed consent.The visual acuity,Ocular Surface Disease Index (OSDI) questionnaire,osmotic pressure of tear,tear film breakup time (TFBUT),corneal fluorescein staining,conjunctival lissamine green staining,Shirmer Ⅰ test (S Ⅰ t) without anesthesia and meibomian function were examined in turn in the subjects,and lateral eyes with higher tear osmotic pressure were analyzed.The differences in above indexes among the different groups were statistically compared,and the correlations between the osmotic pressure of tear and clinical parameters were assessed.Results The osmotic pressure of tear was (326.46 ±22.66) mOsm/L in the dry eye group,which was significantly higher than (296.60± 10.81) mOsm/L in the normal control group (P＜0.05),and the OSDI scores,TFBUT,corneal fluorescine scores,conjunctival staining scores and S Ⅰ t values in the dry eye group were remarkably elevated in comparison with the normal control group (all at P＜0.05).The osmotic pressure of tear was (341.90 ± 21.15) mOsm/L in the severe dry eye group,which was significantly higher than (310.50±8.99) mOsm/L in the mild and moderate group (P＜0.017).The area under the curve for tear osmolarity in the dry eye group was 0.916,and cutoff value of sensitivity and specificity in dry eye diagnosis was 308 mOsm/L,with the sensitivity value 0.79 and specificity 1.00.The significant correlations were found between the osmotic pressure of tear and OSDI scores,corneal fluorescine scores,conjunctival staining scores and S Ⅰ t outcomes (r=0.338,0.407,0.246,-0.461,all at P＜0.05).However,the osmotic pressure of tear was not correlated with TFBUT (r=-0.113,P＞0.05).Conclusions Tears osmotic pressure might be a useful indicator for the diagnosis of dry eye and assessment of severity.A combined application of tear osmolarity measurement with other relevant indexes can improve the diagnostic value.

Oral hydration in children with cerebral palsy

AIM: To investigate whether oral motor performance is determinant for the hydration status and the effect of a supplemental oral fluid supply on salivary osmolality. METHODS: The sample consisted of 99 children with cerebral palsy aged 6 to 13 years old. In this study, children participated in 2-day evaluations: 1st day - baseline: saliva collection, caries experience and oral motor performance evaluations; and 2nd day: saliva collection after supplemental fluid supply. Prior to each evaluation, the participants were trained for saliva collection. Unstimulated whole saliva was collected using cotton roll at baseline, with the amount of fluid usually offered by caregivers, and 48 h after baseline, with as much as twice the normal daily fluid intake previously offered. Salivary osmolality was measured using a freezing point depression osmometer. Caries experience index for decayed, missed and filled teeth (DMFT) was evaluated. According to the Oral Motor Assessment Scale, the children were classified into subfunctional or functional groups. Chi-square, Student's t test and Pearson's correlation coefficient were used. RESULTS: The subfunctional group presented a higher percentage of quadriplegic children (p<0.001), with significantly higher values for caries experience (p<0.001) and salivary osmolality (p<0.001), which did not diminish when supplemental fluid supply was offered, compared with the functional group (p=0.001). CONCLUSIONS: The effectiveness of oral motor performance plays an important role in the hydration status of children with cerebral palsy and those with worse oral motor performance may be at higher risk of oral diseases...

Inflammatory Cytokine and Osmolarity Changes in the Tears of Dry Eye Patients Treated with Topical 1% Methylprednisolone

PURPOSE: To evaluate changes in clinical outcomes, inflammatory cytokine levels, and tear osmolarity in the tears of patients with moderate to severe dry eye syndrome before and after the application of topical 1% methylprednisolone. MATERIALS AND METHODS: Thirty-two patients with moderate to severe dry eye unresponsive to previous aqueous enhancement therapy were enrolled. Five patients were lost to follow up, and twenty-seven patients were eligible for analysis. Patients were instructed to apply topical 1% methylprednisolone four times per day, as well as to continue applying their current therapy of preservative-free 0.1% sodium hyaluronate four times per day. Corneal and conjunctival staining scores, tear film breakup time (TFBUT), Schirmer test, and tear osmolarity were assessed at baseline, 4 weeks, and 8 weeks. Tear samples were collected at every visit for cytokine analysis. RESULTS: Corneal and conjunctival staining scores and TFBUT showed significant improvement at 4 (p<0.001, <0.001, <0.001 respectively) and 8 (p<0.001, <0.001, <0.001 respectively) weeks. Tear osmolarity decreased significantly at 8 weeks (p=0.008). Interleukin (IL)-1beta, IL-8, and monocyte chemoattractant protein-1 were significantly decreased at 8 weeks compared with those at baseline (p=0.041, 0.001, 0.008 respectively). CONCLUSION: Short-term treatment with topical 1% methylprednisolone not only improved clinical outcomes, but also decreased tear osmolarity and cytokine levels. By measuring the changes in cytokine levels and tear osmolarity, we could objectively evaluate the anti-inflammatory effects of topical methylprednisolone applied in the treatment of patients with moderate to severe dry eye syndrome.

Experiência de cárie e osmolaridade salivar em crianças com paralisia cerebral / Caries experience and salivary osmolality in cerebral palsy children

Introdução: Estudos têm demonstrado que quanto maior a severidade do dano neurológico em crianças com paralisia cerebral (PC), maior é o risco de doenças orais. Objetivo: Correlacionar a experiência de cárie com a osmolaridade salivar em crianças com PC. Material e Método: Participaram do estudo 99 crianças (9,2±2,3 anos) com PC, em tratamento reabilitacional. A saliva de repouso foi coletada no período matutino, utilizando rolos absorventes (Salivette®) por cinco minutos. A osmolaridade salivar foi medida por depressão do ponto de congelamento em osmômetro. As avaliações incluíram a experiência de cárie pelo índice de dentes cariados, perdidos e obturados (CPOD), e o motor oral durante o processo de alimentação da criança. Foram utilizados os testes Qui-quadrado, t de Student, Correlação de Spearman e razão de chances (OR), com nível de significância de 5%. Resultado: O grupo 1 (G1) foi composto por 41 crianças livres de cárie e o grupo 2 (G2), por 58 crianças com cárie (CPOD=3,5±2,7). Os grupos foram homogêneos para gênero (p=0,884) e idade (p=0,174). Entretanto, diferiram significantemente com relação à motricidade oral, apresentando G2 maiores porcentagens de crianças com motor oral subfuncional (p<0,001) e tetraparéticos (p=0,001). O G2 apresentou valores significantemente maiores (p<0,001) para osmolaridade (99,6±36,7mOsml) quando comparado ao G1 (76,7±15,9mOsml). Observou-se uma correlação significante entre osmolaridade e experiência de cárie (p<0,001). Apresentar osmolaridade superior a 76,7 (OR=5,18; 1,85 a 14,83) foi determinante individual de maior probabilidade de apresentar risco de cárie (CPOD>0). Conclusão: Maiores valores de osmolaridade salivar aumentam o risco de cárie em crianças com PC.

Introduction: Studies have shown that the greater the severity of neurological damage in children with cerebral palsy (CP), the greater risk of oral diseases. Objective: To correlate the caries experience with salivary osmolality in children with CP. Material and Method: 99 CP children (9.2±2.3 years) in rehabilitation treatment participated of this study. Unstimulated whole saliva was collected in the morning using cotton roll (Salivette®) for 5 minutes. The salivar osmolality was measured using a freezing point depression osmometer. Caries experience index for decayed, missing and filled teeth (DMFT) and oral motor were assessed during the feeding process. It was used the chi-square test, t Student test, Spearman correlation and odds ratio (OR) with a significance level of 5%. Result: Group 1 (G1) consisted of 41 caries-free children, and group 2 (G2) of 58 children with caries (DMFT=3.5±2.7). The groups were homogeneous for gender (p=0.884) and age (p=0.174). However, they differed significantly with respect to the oral motor, with G2 showing higher percentages of children with sub-functional (p<0.001) and tetraparetic (p=0.001) oral motor. Group 2 showed significantly higher values (p<0.001) for salivar osmolarity (99.6±36.7 mOsml) compared to G1 (76.7±15.9 mOsml). There was a significant correlation between osmolality and caries experience (p<0.001). Presenting osmolality greater than 76.7 (OR=5.18, 1.85 to 14.83) was a individual determinant of higher probability for caries risk (DMFT>0). Conclusion: Higher values of salivary osmolality increase the risk of caries in CP children.

Enfoque práctico para el diagnóstico y tratamiento de los estados poliúricos en pacientes con injuria cerebral aguda / Diagnosis and therapy of polyuric states in patients with acute cerebral injury

In patients with acute cerebral injury, polyuric states can potentially trigger, maintain and aggravate the primary neurological damage, due to hypovolemia, arterial hypotension and alterations of osmolarity. The true incidence of the condition in this population is unknown. A widely validated definition of polyuric state is lacking and its etiology is multifactorial. There are two principal classes of polyuria: a) aqueous polyuria with diabetes insipidus as the main cause; and b) osmotic polyuria in which sodium, glucose or ureaplay the main role. Polyuric states are in close association with disorders of water and sodium metabolism and with alterations in acid-base balance. A detailed analysis of the history, clinical picture and simple laboratory determinations in blood and urine, are required for an adequate assessment of these polyuric states. The problem must be faced with pathophysiological reasoning and a systematic and sequential approach, because each disorder needs a specific therapy.

Two Cases of Ethylene Glycol Poisoning

Ethylene glycol poisoning is treated mainly by alcohol dehydrogenase inhibition therapy and hemodialysis. Early recognition and initiation of treatment is important because toxic metabolites increase over time by hepatic metabolism; however, there is no confirmative diagnostic tool in our clinical setting. Therefore, diagnosis is dependent on history, high anion gap acidosis, high osmolal gap, etc.. Diagnosis and treatment are delayed in cases where history taking is not possible, such as a mental changed patient. Authors report on two cases of ethylene glycol poisoning by contrasting clinical outcomes, demonstrating the importance of early diagnosis and treatment for achievement of a good outcome.