Nadja C. Pereira

Posição prona e diminuição da assincronia toracoabdominal em recém-nascidos prematuros

OBJECTIVE: To assess the effect of prone and supine positions on breathing pattern variables, thoracoabdominal motion and peripheral oxygen saturation of hemoglobin of premature newborn infants recovering from respiratory distress syndrome, while breathing spontaneously and in rapid eye movement sleep. METHODS: This was a quasi-experimental study. Twelve preterms weighing > 1,000 g at enrollment were studied in both positions, in random order. Respiratory inductive plethysmography was used to analyze breathing pattern (tidal volume, respiratory rate, minute ventilation, mean inspiratory flow) and thoracoabdominal motion (labored breathing index, phase relation in inspiration, phase relation in expiration, phase relation in total breath and phase angle). Pulse oximetry was used to evaluate peripheral oxygen saturation. Students t test for paired samples or the Wilcoxon test were used for statistical analysis. Significance was set at p < 0.05. RESULTS: A total of 9,167 respiratory cycles were analyzed. The prone position was associated with significant reductions in labored breathing index (-0.84±0.69; p = 0.001; 95%CI -1.29 to -0.40), phase relation in inspiration (-27.36±17.55; p = 0.000; 95%CI -38.51 to -16.20), phase relation in expiration (-32.36±16.20; p = 0.000; 95%CI -42.65 to -22.06) and phase relation in total breath (-30.20±14.76; p = 0.000; 95%CI -39.59 to -20.82). There were no significant differences between the two positions in any of the other variables analyzed. CONCLUSION: The prone position resulted in a significant reduction in thoracoabdominal asynchrony, without affecting breathing pattern or peripheral oxygen saturation.

Prone position and reduced thoracoabdominal asynchrony in preterm newborns

OBJECTIVE To assess the effect of prone and supine positions on breathing pattern variables, thoracoabdominal motion and peripheral oxygen saturation of hemoglobin of premature newborn infants recovering from respiratory distress syndrome, while breathing spontaneously and in rapid eye movement sleep. METHODS This was a quasi-experimental study. Twelve preterms weighing > 1,000 g at enrollment were studied in both positions, in random order. Respiratory inductive plethysmography was used to analyze breathing pattern (tidal volume, respiratory rate, minute ventilation, mean inspiratory flow) and thoracoabdominal motion (labored breathing index, phase relation in inspiration, phase relation in expiration, phase relation in total breath and phase angle). Pulse oximetry was used to evaluate peripheral oxygen saturation. Students t test for paired samples or the Wilcoxon test were used for statistical analysis. Significance was set at p < 0.05. RESULTS A total of 9,167 respiratory cycles were analyzed. The prone position was associated with significant reductions in labored breathing index (-0.84+/-0.69; p = 0.001; 95%CI -1.29 to -0.40), phase relation in inspiration (-27.36+/-17.55; p = 0.000; 95%CI -38.51 to -16.20), phase relation in expiration (-32.36+/-16.20; p = 0.000; 95%CI -42.65 to -22.06) and phase relation in total breath (-30.20+/-14.76; p = 0.000; 95%CI -39.59 to -20.82). There were no significant differences between the two positions in any of the other variables analyzed. CONCLUSION The prone position resulted in a significant reduction in thoracoabdominal asynchrony, without affecting breathing pattern or peripheral oxygen saturation.

Maximum respiratory pressure measuring system: calibration and evaluation of uncertainty

The objective of this paper is to present a methodology for the evaluation of uncertainties in the measurements results obtained during the calibration of a digital manovacuometer prototype (DM) with a load cell sensor pressure device incorporated. Calibration curves were obtained for both pressure sensors of the DM using linear regression by weighted least squares method (WLS). Two models were built to evaluate uncertainty. One takes into account the information listed in the sensor datasheet, resulting in the maximum permissible measurement error of the manovacuometer, and the other on the WLS implemented during calibration. Considering a range of ten calibration points, it was found that calibration procedure designed using WLS modeling indicates that the range of measurement uncertainty extends from 0.2 up to 0.5 kPa. This is inside the manufacter range that extends from 1.5 up 3.5 kPa, showing adequacy for use.

Teste de esforço cardiopulmonar com protocolo de rampa em adultos com insuficiência cardíaca

INTRODUCAO E OBJETIVO: O teste de esforco com protocolo de rampa e descrito como o que mais se adequa a condicao fisica de individuos com insuficiencia cardiaca (IC). Porem, nao ha padronizacao descrita sobre incrementos de velocidade e inclinacao. Este estudo teve como objetivo descrever resultados encontrados a partir da aplicacao de um teste de esforco com protocolo de rampa adaptado para individuos com IC, classes II e III da New York Heart Association (NYHA). METODOS: 41 individuos com media de idade de 46,37 ± 8,98 anos e fracao de ejecao de 31,51 ± 9,45% fizeram o teste de esforco com analise de gases expirados em esteira, com protocolo de rampa desenvolvido a partir de criterios definidos pelo estudo de Barbosa e Silva e Sobral. Analise estatistica: Foi realizada analise descritiva com distribuicao de frequencia e o tempo de teste foi apresentado como media ± desvio padrao. Foi realizado o modelo de regressao linear incluindo classe da NYHA, idade e fracao de ejecao como variaveis explicativas para tempo de teste. Foi considerado significativo p < 0,05. RESULTADOS: O tempo medio do teste foi 8,89 ± 3,57 minutos e o R alcancado foi 1,12 ± 0,11. Sessenta e um porcento da amostra apresentou duracao do teste entre seis e 12 minutos, considerando intervalo de media ± 1 desvio padrao, e 73,2% da amostra apresentou duracao entre seis e 15 minutos. CONCLUSAO: Os achados deste estudo demonstraram que a maioria dos individuos com IC finalizou o teste com o protocolo de rampa adaptado dentro da duracao considerada adequada pela literatura.