Sodium restriction in patients with chronic heart failure and reduced ejection fraction: A randomized controlled trial.

BACKGROUND: Sodium restriction is recommended for patients with heart failure (HF) despite the lack of solid clinical evidence from randomized controlled trials. Whether or not sodium restrictions provide beneficial cardiac effects is not known. METHODS: The present study is a randomized, double-blind, controlled trial of stable HF patients with ejection fraction ≤ 40%. Patients were allocated to sodium restriction (2 g of sodium/day) vs. control (3 g of sodium/day). The primary outcome was change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 20 weeks. Secondary outcomes included quality of life and adverse safety events (HF readmission, blood pressure or electrolyte abnormalities). RESULTS: Seventy patients were enrolled. Median baseline sodium consumption was 3268 (2225-4537) mg/day. Adherence to the intervention based on 24-hour urinary sodium was 32%. NT-proBNP and quality of life did not significantly change between groups (p > 0.05 for both). Adverse safety events were not significantly different between the arms (p > 0.6 for all). In the per protocol analysis, patients who achieved a sodium intake < 2500 mg/day at the intervention conclusion showed improvements in NT-proBNP levels (between-group difference: -55%, 95% confidence interval -27 to -73%; p = 0.002) and quality of life (between-group difference: -11 ± 5 points; p = 0.04). Blood pressure decreased in patients with lower sodium intake (between-group difference: -9 ± 5 mmHg; p = 0.05) without significant differences in symptomatic hypotension or other safety events (p > 0.3 for all). CONCLUSIONS: Adherence assessed by 24-hour natriuresis and by the nutritionist was poor. The group allocated to sodium restriction did not show improvement in NT-proBNP. However, patients who achieved a sodium intake < 2500 mg/day appeared to have improvements in NT-proBNP and quality of life without any adverse safety signals. CLINICALTRIALS: gov Identifier: NCT03351283.

Variability of arterial and peripheral venous blood gases parameters in subjects with stable obstructive pulmonary disease / Variabilidad de los parámetros de la gasometría arterial y venosa periférica en sujetos con enfermedad pulmonar obstructiva crónica en condición estable

Background: Peripheral venous blood gases may be useful in subjects with exacerbation of chronic obstructive pulmonary disease to evaluate their gas exchange. Objective: To describe the variability of parameters of arterial and peripheral venous blood gases in subjects with stable obstructive pulmonary disease. Methods: Cross-sectional design, consecutive subjects were studied in a blinded manner, while arterial and peripheral venous blood was obtained for analysis. Variability was established with Bland-Altman statistical method and its magnitude with the intraclass correlation coefficient (95 % confidence interval). Results: Three hundred blood samples from 150 patients were studied, 89 (59.3%) women, age 66 ± 10 years old, body mass index 28.44 ± 4.81 Kg/m2. Mean difference (bias) [intraclass correlation coeficient] pH 0.012 (-0.009, 0.032) [0.927], Carbon dioxide pressure -6.5 (-14.1, 1.1) [ 0.643], serum bicarbonate -1.3 (-3.3, 0.7) [0.929], base excess -1 (-4, 2.1) [0.904], hemoglobin -0.1 (-1.9, 1.8) [0.947]. Conclusions: The variability of pH, serum bicarbonate, and hemoglobin are similar in both blood samples. These arterial or peripheral venous blood gas parameters could be used interchangeably.

Introducción: la gasometría venosa periférica puede ser de utilidad en sujetos con exacerbación de la enfermedad pulmonar obstructiva crónica para evaluar su intercambio gaseoso. Objetivo: describir la variabilidad de los parámetros de la gasometría arterial y venosa periférica en sujetos con enfermedad pulmonar obstructiva crónica en condición estable. Métodos: diseño transversal, se estudiaron sujetos consecutivos de forma cegada, al mismo tiempo se obtuvo sangre arterial y venosa periférica para su análisis. La variabilidad se determinó con el método estadístico de Bland-Altman y su magnitud con el coeficiente de correlación intraclase (intervalo de confianza al 95%). Resultados: se estudiaron 300 muestras sanguíneas de 150 pacientes, 89 mujeres (59.3%), edad del grupo 66 ± 10 años, el índice de masa corporal 28.44 ± 4.81 Kg/m2. La diferencia media (sesgo) [coeficiente de correlación intraclase] para el pH: 0.012 (-0.009, 0.032) [0.927], presión de bióxido de carbono: -6.5 (-14.1, 1.1) [ 0.643], bicarbonato sérico: -1.3 (-3.3, 0.7) [0.929], y exceso de base: -1 (-4, 2.1) [0.904], hemoglobina: -0.1 (-1.9, 1.8) [0.947]. Conclusiones: la variabilidad del pH, el bicarbonato sérico y la hemoglobina son similares en ambas muestras sanguíneas. Estos parámetros de la gasometría arterial o venosa periférica podrían ser utilizados en forma intercambiable.