Análise comparativa entre a dosagem do lactato no líquor e sua detecção atráves da espectroscopia de prótons por ressonância magnética / Comparative analysis between lactate biochemical dosage in cerebrospinal fluid and its detection by proton magnetic resonance spectroscopy

INTRODUÇÃO: A dosagem bioquímica do lactato no líquor (LCR) é um procedimento rotineiro e necessário na investigação diagnóstica e no acompanhamento evolutivo de várias doenças neurológicas, como, por exemplo, as doenças mitocondriais (DM). Pacientes com DM e comprometimento do sistema nervoso central frequentemente apresentam aumento do lactato no LCR. O lactato no LCR também pode ser detectado através da espectroscopia de prótons através da ressonância magnética (ERM), uma técnica não invasiva que pode ser empregada juntamente com as imagens estruturais obtidas através da ressonância magnética (RM). Nosso objetivo neste estudo é avaliar a existência ou não de correlação entre a dosagem bioquímica do lactato no LCR e no sangue e a sua quantificação através da ERM em pacientes em investigação de encefalopatia mitocondrial. Não é de nosso conhecimento a existência de estudos semelhantes in vivo na literatura médica. MÉTODOS: 22 pacientes (idades entre 9 meses e 20 anos) em investigação diagnóstica por suspeita clínica de encefalopatia relacionada a DM participara deste estudo prospectivo realizado entre novembro de 2005 a novembro de 2006. Foram comparados os valores do lactato nas dosagens séricas e liquóricas. Todos os pacientes realizaram RM e ERM e, quando presente, analisou-se o pico do lactato (PL). Os dados da quantificação do lactato obtidos nestas três modalidades foram comparados. RESULTADOS: A análise de correlação demonstrou evidências de associação entre as variáveis PL à ERM e lactato liquórico (p=0,001); não foi evidenciada correlação entre os valores do PL à ERM e as medidas sanguíneas dessa substância (p=0,736) e entre as dosagens bioquímicas liquórica e sanguínea (p=0,937). CONCLUSÕES: Este estudo demonstrou a existência de correlação entre a dosagem bioquímica do lactato no LCR e o PL obtido através de ERM. A ERM do LCR é uma técnica factível e recomendamos que a mesma seja empregada rotineiramente em pacientes com suspeita ou em...

INTRODUCTION: The cerebrospinal fluid (CSF) lactate biochemical dosage is a routine and a requisite procedure to evaluate and to monitor many neurological diseases, such as mitochondrial disease (MD). Patients with MD and central nervous system (CNS) involvement, usually show an increase of CSF lactate. Another choice to study the lactate instead of CSF biochemical dosage is the CSF magnetic resonance proton spectroscopy (SRM), a noninvasive technique, which can be employed as an adjunct tool with structural magnetic resonance imaging (MRI). Our objective is to study the correlation between the CSF and blood lactate dosages and the SRM lactate quantification in patients under investigation for the MD encephalopathy. To our knowledge there is no report of similar studies in vivo in the literature. METHODS: 22 patients (aging 9 months to 20 years old) under investigation for MD encephalopathy were elected for this prospective study between November 2005 and December 2006. The lactate levels were analyzed by biochemical dosages in the CSF and blood serum. Brain MRI was performed for all patients and the lactate peak (LP) obtained from SRM was analyzed. All lactate level data obtained from the three different sources were compared. RESULTS: The statistical analysis demonstrated a correlation between the LP at SRM and the CSF lactate dosage (p=0.0001); no correlation was observed between the LP and the blood lactate (p=0.736) as well the blood lactate and CSF lactate (p=0.937). CONCLUSION: Our study showed correlation between the lactate level in the CSF biochemical dosage and the LP found on SRM. The CSF SRM is tangible technique and we recommend it to be applied in the daily clinical practice to evaluate suspicious and diagnosed CNS compromised ME patients.

Air trapping: The major factor limiting diaphragm mobility in chronic obstructive pulmonary disease patients.

BACKGROUND AND OBJECTIVE: Patients with COPD can have impaired diaphragm mechanics. A new method of assessing the mobility of the diaphragm, using ultrasound, has recently been validated. This study evaluated the relationship between pulmonary function and diaphragm mobility, as well as that between respiratory muscle strength and diaphragm mobility, in COPD patients. METHODS: COPD patients with pulmonary hyperinflation (n = 54) and healthy subjects (n = 20) were studied. Patients were tested for pulmonary function, maximal respiratory pressures and diaphragm mobility using ultrasound to measure the craniocaudal displacement of the left branch of the portal vein. RESULTS: COPD patients had less diaphragm mobility than did healthy individuals (36.5 +/- 10.9 mm vs 46.3 +/- 9.5 mm, P = 0.001). In COPD patients, diaphragm mobility correlated strongly with pulmonary function parameters that quantify air trapping (RV: r = -0.60, P < 0.001; RV/TLC: r = -0.76, P < 0.001), moderately with airway obstruction (FEV(1): r = 0.55, P < 0.001; airway resistance: r = -0.32, P = 0.02) and weakly with pulmonary hyperinflation (TLC: r = -0.28, P = 0.04). No relationship was observed between diaphragm mobility and respiratory muscle strength (maximal inspiratory pressure: r = -0.11, P = 0.43; maximal expiratory pressure: r = 0.03, P = 0.80). CONCLUSION: The results of this study suggest that the reduction in diaphragm mobility in COPD patients is mainly due to air trapping and is not influenced by respiratory muscle strength or pulmonary hyperinflation.

Ultrasound evaluation of diaphragmatic mobility in different postures in healthy subjects.

OBJECTIVE: To assess, using ultrasound, the effects that changes in body position have on diaphragmatic mobility in healthy subjects during spontaneous breathing. METHODS: The study involved seven healthy female volunteers, all of whom were nonsmokers, well nourished, and free of any cardiopulmonary disease. They were submitted to pulmonary function testing and ultrasound evaluation of the mobility of the right diaphragm by the craniocaudal displacement of the left branch of the portal vein using an ultrasound device in mode B. The mobility of the right diaphragm was evaluated in right decubitus and in left decubitus. The order of evaluation was previously determined in a random drawing. RESULTS: The average mobility of the right diaphragm in right decubitus (51.30 +/- 9.69 mm) was significantly higher (p = 0.03) than that observed in left decubitus (45.93 +/- 10.37 mm). CONCLUSION: The results suggest that, during spontaneous ventilation, the dependent portion of the diaphragm presents greater mobility than does the nondependent portion, and that the technique used was sufficiently sensitive to detect variations in diaphragmatic mobility related to changes in posture.

Avaliação ultra-sonográfica da mobilidade do diafragma em diferentes posturas em sujeitos saudáveis / Ultrasound evaluation of diaphragmatic mobility in different postures in healthy subjects

OBJETIVO: Avaliar, por meio de ultra-sonografia, o efeito da mudança de posicionamento corporal na mobilidade diafragmática de sujeitos saudáveis durante a respiração espontânea. MÉTODOS: Foram avaliadas sete mulheres voluntárias, saudáveis, sem histórico clínico de doenças cárdio-respiratórias, não tabagistas e eutróficas. Os sujeitos foram submetidos à prova de função pulmonar e à avaliação ultra-sonográfica da mobilidade do diafragma direito através do deslocamento crânio-caudal do ramo esquerdo da veia porta, utilizando-se um aparelho de ultra-sonografia no modo B. A mobilidade do diafragma direito foi avaliada em decúbito lateral direito e em decúbito lateral esquerdo, e a ordem de avaliação das posturas foi definida aleatoriamente por meio de um sorteio prévio. RESULTADOS: A média da excursão do diafragma direito em decúbito lateral direito (51,30 ± 9,69 mm) foi significativamente maior (p = 0,03) que em decúbito lateral esquerdo (45,93 ± 10,37 mm). CONCLUSÃO: Os resultados sugerem que, durante a ventilação espontânea, a mobilidade da porção dependente do diafragma é maior do que a da não dependente e que a técnica empregada foi sensível para detectar variações da mobilidade do diafragma com as mudanças de posicionamento.

OBJECTIVE: To assess, using ultrasound, the effects that changes in body position have on diaphragmatic mobility in healthy subjects during spontaneous breathing. METHODS: The study involved seven healthy female volunteers, all of whom were nonsmokers, well nourished, and free of any cardiopulmonary disease. They were submitted to pulmonary function testing and ultrasound evaluation of the mobility of the right diaphragm by the craniocaudal displacement of the left branch of the portal vein using an ultrasound device in mode B. The mobility of the right diaphragm was evaluated in right decubitus and in left decubitus. The order of evaluation was previously determined in a random drawing. RESULTS: The average mobility of the right diaphragm in right decubitus (51.30 ± 9.69 mm) was significantly higher (p = 0.03) than that observed in left decubitus (45.93 ± 10.37 mm). CONCLUSION: The results suggest that, during spontaneous ventilation, the dependent portion of the diaphragm presents greater mobility than does the nondependent portion, and that the technique used was sufficiently sensitive to detect variations in diaphragmatic mobility related to changes in posture.

Blood pressure and kidney size in term newborns with intrauterine growth restriction.

CONTEXT AND OBJECTIVE: Low birth weight is associated with higher blood pressure in childhood and adulthood. The aim of this study was to investigate the influence of intrauterine growth restriction (IUGR) on newborn systolic blood pressure (SBP). DESIGN AND SETTING: Prospective comparative study at Neonatal and Intensive in Clinical Pediatrics Division, Maternity Hospital in Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo. METHODS: 35 newborns with IUGR and 35 without IUGR were compared. Healthy term newborns without malformations, with Apgar score at fifth minute > 6 were included. Birth weight, kidney weight/birth weight ratio, kidney weight (ultrasound scan), plasma renin activity (PRA) and SBP evolution were analyzed during the first month of life (on 1st, 3rd, 7th and 30th days). RESULTS: SBP evolution, kidney weight/birth weight ratio and PRA did not differ between the two groups. In newborns with IUGR, SBP presented positive correlations with birth weight (r = 0.387 p = 0.026) and BMI (r = 0.412 p = 0.017) on the 7th day of life. Positive correlations with birth weight (r = 0.440 p = 0.01) and birth length (r = 0.386 p = 0.026) were also seen on the 30th day. There was an inverse correlation on the 7th day between SBP and kidney weight/birth weight ratio (r = -0.420 p = 0.014), but this did not persist to the end of the month. CONCLUSIONS: IUGR seems not to have any influence on SBP, PRA or kidney weight among term newborns during their first month of life.

Blood pressure and kidney size in term newborns with intrauterine growth restriction

CONTEXT AND OBJECTIVE: Low birth weight is associated with higher blood pressure in childhood and adulthood. The aim of this study was to investigate the influence of intrauterine growth restriction (IUGR) on newborn systolic blood pressure (SBP). DESIGN AND SETTING: Prospective comparative study at Neonatal and Intensive in Clinical Pediatrics Division, Maternity Hospital in Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo. METHODS: 35 newborns with IUGR and 35 without IUGR were compared. Healthy term newborns without malformations, with Apgar score at fifth minute > 6 were included. Birth weight, kidney weight/birth weight ratio, kidney weight (ultrasound scan), plasma renin activity (PRA) and SBP evolution were analyzed during the first month of life (on 1st, 3rd, 7th and 30th days). RESULTS: SBP evolution, kidney weight/birth weight ratio and PRA did not differ between the two groups. In newborns with IUGR, SBP presented positive correlations with birth weight (r = 0.387 p = 0.026) and BMI (r = 0.412 p = 0.017) on the 7th day of life. Positive correlations with birth weight (r = 0.440 p = 0.01) and birth length (r = 0.386 p = 0.026) were also seen on the 30th day. There was an inverse correlation on the 7th day between SBP and kidney weight/birth weight ratio (r = -0.420 p = 0.014), but this did not persist to the end of the month. CONCLUSIONS: IUGR seems not to have any influence on SBP, PRA or kidney weight among term newborns during their first month of life.

CONTEXTO E OBJETIVO: O baixo peso ao nascimento está associado à pressão arterial mais elevada na criança e no adulto. O objetivo foi avaliar a influência do retardo do crescimento intra-uterino (RCIU) na pressão arterial sistólica de recém-nascidos (PAS). TIPO DE ESTUDO E LOCAL: Estudo prospectivo, realizado no berçário anexo à maternidade, Instituto da Criança, Hospital das Clínicas da Universidade de São Paulo. MÉTODOS: 35 recém-nascidos (RN) com RCIU e 35 RN sem RCIU foram avaliados em um estudo prospectivo. Os critérios de inclusão foram: recém-nascidos no termo, saudáveis, sem malformações e índice de Apgar de quinto minuto > 6. Parâmetros antropométricos (peso ao nascimento, relação comprimento renal/peso ao nascimento), dimensões renais (pela ultra-sonografia), dosagem da atividade da renina plasmática (ARP) e a evolução da PAS foram analisadas durante o primeiro mês de vida (no 1°, 3°, 7° e 30° dias de vida). RESULTADOS: A evolução da PAS, relação peso renal/peso ao nascimento e ARP não apresentaram diferença entre os dois grupos. Em recém-nascidos com CIUR, a correlação entre PAS e PN (r = 0,387 p = 0,026) e IMC (r = 0,412 p = 0,017) foi positiva no 7° dia de vida. No 30° dia de vida, a correlação com PN (r = 0,440 p = 0,01) e comprimento ao nascimento (r = 0,386 p = 0,026) também foi positiva. Houve correlação negativa entre a PAS do 7° dia e a relação peso do rim/peso ao nascimento (r = - 0,420 p = 0,014), porém, esta correlação não persistiu ao longo do primeiro mês de vida. CONCLUSÕES: RCIU parece não influenciar a PAS, a atividade de renina plasmática ou o peso renal em recém-nascidos no termo durante o primeiro mês de vida.