RESUMEN
We studied functional changes in rat pituitary-thyroid axis after a short-term shift in deuterium body content. Male Wistar rats consumed deuterium-enriched (500,000 ppm) or deuterium-depleted water (10 ppm) for 24 h. Rats of both experimental groups demonstrated elevated concentration of bound with transport proteins thyroxine and reduced level of thyroid-stimulating hormone in serum. No changes in the rate of thyroxine conversion to triiodothyronine were found. Thus, both the increase and reduction of deuterium body content produced similar changes in the function of the pituitary-thyroid axis with primary affection of the thyroid gland, indicative of its higher sensitivity to shift in deuterium levels.
Asunto(s)
Deuterio/farmacología , Transferencias de Fluidos Corporales/efectos de los fármacos , Hipófisis/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Animales , Líquidos Corporales/química , Líquidos Corporales/efectos de los fármacos , Líquidos Corporales/metabolismo , Peso Corporal/efectos de los fármacos , Deuterio/metabolismo , Transferencias de Fluidos Corporales/fisiología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Hipófisis/metabolismo , Ratas , Ratas Wistar , Glándula Tiroides/metabolismo , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Equilibrio Hidroelectrolítico/efectos de los fármacosRESUMEN
BACKGROUND: Large differences in glymphatic system transport-similar in magnitude to those of the sleep/wake cycle-have been observed during anesthesia with dexmedetomidine supplemented with low dose isoflurane (DEXM-I) in comparison to isoflurane (ISO). However, the biophysical and bioenergetic tissue status underlying glymphatic transport differences between anesthetics remains undefined. To further understand biophysical characteristics underlying these differences we investigated volume status across cerebral tissue compartments, water diffusivity, and T2* values in rats anesthetized with DEXM-I in comparison to ISO. METHODS: Using a crossover study design, a group of 12 Sprague Dawley female rats underwent repetitive magnetic resonance imaging (MRI) under ISO and DEXM-I. Physiological parameters were continuously measured. MRI included a proton density weighted (PDW) scan to investigate cerebrospinal fluid (CSF) and parenchymal volumetric changes, a multigradient echo scan (MGE) to calculate T2* maps as a measure of 'bioenergetics', and a diffusion scan to quantify the apparent diffusion coefficient (ADC). RESULTS: The heart rate was lower with DEXM-I in comparison to ISO, but all other physiological variables were similar across scans and groups. The PDW images revealed a 1% parenchymal volume increase with ISO compared to DEXM-I comprising multiple focal tissue areas scattered across the forebrain. In contrast, with DEXM-I the CSF compartment was enlarged by ~ 6% in comparison to ISO at the level of the basal cisterns and peri-arterial conduits which are main CSF influx routes for glymphatic transport. The T2* maps showed brain-wide increases in T2* in ISO compared to DEXM-I rats. Diffusion-weighted images yielded no significant differences in ADCs across the two anesthesia groups. CONCLUSIONS: We demonstrated CSF volume expansion with DEXM-I (in comparison to ISO) and parenchymal (GM) expansion with ISO (in comparison to DEXM-I), which may explain the differences in glymphatic transport. The T2* changes in ISO are suggestive of an increased bioenergetic state associated with excess cellular firing/bursting when compared to DEXM-I.
Asunto(s)
Anestésicos/farmacología , Líquido Cefalorraquídeo/efectos de los fármacos , Dexmedetomidina/farmacología , Transferencias de Fluidos Corporales/efectos de los fármacos , Sistema Glinfático/efectos de los fármacos , Sustancia Gris/efectos de los fármacos , Isoflurano/farmacología , Animales , Líquido Cefalorraquídeo/diagnóstico por imagen , Estudios Cruzados , Femenino , Sistema Glinfático/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Imagen por Resonancia Magnética , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: Ultrafiltration decreases total body water and improves the alveolar to arterial oxygen gradient. The aims of the study were to investigate the efficacy and safety of early ultrafiltration in acute decompensated heart failure (ADHF) patients. METHODS: 100 patients with ADHF within 24 h of admission were randomly assigned into early ultrafiltration (n = 40) or torasemide plus tolvaptan (n = 60) groups. The primary outcomes were weight loss and an increase in urine output on days 4 and 8 of treatment. RESULTS: Patients who received early ultrafiltration for 3 days achieved a greater weight loss (kg) (- 2.94 ± 3.76 vs - 0.64 ± 0.91, P < 0.001) and urine increase (mL) (198.00 ± 170.70 vs 61.77 ± 4.67, P < 0.001) than the torasemide plus tolvaptan group on day 4. From days 4 to 7, patients in the early ultrafiltration group received sequential therapy of torasemide and tolvaptan. Better control of volume was reflected in a greater weight loss (- 3.72 ± 3.81 vs - 1.34 ± 1.32, P < 0.001) and urine increase (373.80 ± 120.90 vs 79.5 ± 52.35, P < 0.001), greater reduction of B-type natriuretic peptide (BNP) (pg/mL) (- 1144 ± 1435 vs - 654.02 ± 889.65, P = 0.037), NYHA (New York Heart Association) functional class (- 1.45 ± 0.50 vs - 1.17 ± 0.62, P = 0.018), jugular venous pulse (JVP) score (points) (- 1.9 ± 1.13 vs - 0.78 ± 0.69, P < 0.001), inferior vena cava (IVC) diameter (mm) (- 15.35 ± 11.03 vs - 4.98 ± 6.00, P < 0.001) and an increase in the dyspnea score (points) (4.08 ± 3.44 vs 2.77 ± 2.03, P = 0.035) in the early ultrafiltration group on day 8. No significant differences were found in the readmission and mortality rates in the 2 patient groups at the 1-month and 3-month follow-ups. Both groups had a similar stable renal profile. CONCLUSION: Early ultrafiltration is superior to diuretics for volume overload treatment initiation of ADHF patients. Trial registration Chinese Clinical Trial Registry, ChiCTR2000030696, Registered 10 March 2020-Retrospectively registered, https://www.chictr.org.cn/showproj.aspx?proj=29099 .
Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas/uso terapéutico , Transferencias de Fluidos Corporales/efectos de los fármacos , Insuficiencia Cardíaca/terapia , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/uso terapéutico , Tolvaptán/uso terapéutico , Torasemida/uso terapéutico , Ultrafiltración , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Antagonistas de los Receptores de Hormonas Antidiuréticas/efectos adversos , China , Femenino , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/efectos adversos , Factores de Tiempo , Tolvaptán/efectos adversos , Torasemida/efectos adversos , Resultado del Tratamiento , Ultrafiltración/efectos adversos , Micción/efectos de los fármacos , Pérdida de Peso/efectos de los fármacosRESUMEN
Hemodynamic instability related to renal replacement therapy (HIRRT) is a frequent complication of all renal replacement therapy (RRT) modalities commonly used in the intensive care unit. HIRRT is associated with increased mortality and may impair kidney recovery. Our current understanding of the physiologic basis for HIRRT comes primarily from studies of end-stage kidney disease patients on maintenance hemodialysis in whom HIRRT is referred to as 'intradialytic hypotension'. Nonetheless, there are many studies that provide additional insights into the underlying mechanisms for HIRRT specifically in critically ill patients. In particular, recent evidence challenges the notion that HIRRT is almost entirely related to excessive ultrafiltration. Although excessive ultrafiltration is a key mechanism, multiple other RRT-related mechanisms may precipitate HIRRT and this could have implications for how HIRRT should be managed (e.g., the appropriate response might not always be to reduce ultrafiltration, particularly in the context of significant fluid overload). This review briefly summarizes the incidence and adverse effects of HIRRT and reviews what is currently known regarding the mechanisms underpinning it. This includes consideration of the evidence that exists for various RRT-related interventions to prevent or limit HIRRT. An enhanced understanding of the mechanisms that underlie HIRRT, beyond just excessive ultrafiltration, may lead to more effective RRT-related interventions to mitigate its occurrence and consequences.
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Hemodinámica/fisiología , Terapia de Reemplazo Renal/efectos adversos , Lesión Renal Aguda/fisiopatología , Lesión Renal Aguda/terapia , Transferencias de Fluidos Corporales/efectos de los fármacos , Transferencias de Fluidos Corporales/fisiología , Hemodinámica/efectos de los fármacos , Humanos , Riñón/anomalías , Riñón/metabolismo , Riñón/fisiopatología , Fallo Renal Crónico/etiología , Fallo Renal Crónico/fisiopatología , Concentración Osmolar , Terapia de Reemplazo Renal/métodosRESUMEN
BACKGROUND: This review considers anew the etiology of the cardio-renal protective effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors by extending the discussion to renal congestion, inherent in diabetic kidney disease (DKD) even at an early stage of nephropathy in which heart failure (HF) or salt and water accumulation is asymptomatic. SUMMARY: The interstitial fluid (IF) space of the kidney space plays a crucial role for tubulointerstitial inflammation, renal hypoxia, and ischemic injury, which often leads to renal progression. In DKD, as a result of hyperglycemic milieu, excessive salt and water can be accumulated in the IF space, creating renal congestion. I hypothesize that SGLT2 inhibitors cause a shift in extracellular water from the IF space to the intravascular space to compensate for the SGLT2 inhibitor-induced hypovolemia. This decrease in IF volume ameliorates the IF space milieu and may reduce inflammation, hypoxia, and ischemic injury. Message: The present review proposes a novel theory; unlike other hypoglycemic agents or diuretics, SGLT2 inhibitor could protect DKD from failing by improving latent renal congestion even without symptomatic HF.
Asunto(s)
Nefropatías Diabéticas/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Animales , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/prevención & control , Transferencias de Fluidos Corporales/efectos de los fármacos , Humanos , Sustancias Protectoras , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacologíaRESUMEN
A 73-year-old man with liver cirrhosis and advanced chronic kidney disease was admitted to our hospital due to bilateral lower leg edema and appetite loss. Furosemide to treat fluid retention markedly decreased extracellular water compared with intracellular water, but the addition of tolvaptan equally decreased both with a greater diuretic response than furosemide alone. Furthermore, tolvaptan administration increased the plasma colloid osmotic pressure, which might facilitate the shift of fluid from the extravascular space to the intravascular space. This is the first case showing different effects on the fluid distribution between furosemide and additional tolvaptan in the same patient.
Asunto(s)
Transferencias de Fluidos Corporales/efectos de los fármacos , Furosemida/farmacología , Cirrosis Hepática/complicaciones , Insuficiencia Renal Crónica/complicaciones , Tolvaptán/farmacología , Anciano , Antagonistas de los Receptores de Hormonas Antidiuréticas/farmacología , Antagonistas de los Receptores de Hormonas Antidiuréticas/uso terapéutico , Benzazepinas/farmacología , Benzazepinas/uso terapéutico , Diuréticos/farmacología , Quimioterapia Combinada , Edema/tratamiento farmacológico , Edema/etiología , Edema/fisiopatología , Furosemida/uso terapéutico , Humanos , Pierna , Masculino , Tolvaptán/uso terapéuticoRESUMEN
AIMS: A population kinetic model was developed for the body fluid shifts occurring when 20% albumin is given by intravenous infusion. The aim was to study whether its efficacy to expand the plasma volume is impaired after major surgery. METHODS: An intravenous infusion of 3 mL/kg 20% albumin over 30 minutes was given to 15 volunteers and to 15 patients on the 1st day after major open abdominal surgery. Blood samples and urine were collected during 5 hours. Mixed-effect modelling software was used to develop a fluid volume kinetic model, using blood haemoglobin and urine excretion the estimate body fluid shifts, to which individual-specific covariates were added in sequence. RESULTS: The rise in plasma albumin expanded the plasma volume in excess of the infused volume by relocating noncirculating fluid (rate constant k21 ), but it also increased losses of fluid from the kinetic system (kb ). The balance between k21 and kb maintained the rise in plasma albumin and plasma volume at a virtual steady-state for almost 2 hours. The rate constant for urinary excretion (k10 ) was slightly reduced by the preceding surgery, by a marked rise in plasma albumin, and by a high preinfusion urinary concentration of creatinine. The arterial pressure, body weight, and plasma concentrations of C-reactive protein and shedding products of the endothelial glycocalyx layer (syndecan-1, heparan sulfate, and hyaluronic acid) did not serve as statistically significant covariates. CONCLUSIONS: There were no clinically relevant differences in the kinetics of 20% albumin between postoperative patients and volunteers.
Asunto(s)
Albúminas/farmacocinética , Transferencias de Fluidos Corporales/efectos de los fármacos , Fluidoterapia , Modelos Biológicos , Sustitutos del Plasma/farmacocinética , Abdomen/cirugía , Adulto , Albúminas/administración & dosificación , Albúminas/efectos adversos , Femenino , Humanos , Infusiones Intravenosas , Masculino , Sustitutos del Plasma/administración & dosificación , Sustitutos del Plasma/efectos adversos , Cuidados Posoperatorios , Suecia , Resultado del Tratamiento , Adulto JovenRESUMEN
AIM: Sodium-glucose cotransporter 2 (SGLT2) inhibitors are an antihyperglycemic drug with diuretic properties. We recently reported that an SGLT2 inhibitor ameliorated extracellular fluid expansion with a transient increase in urinary Na+ excretion. However, the effects of SGLT2 inhibitors on fluid distribution in comparison to conventional diuretics remain unclear. METHODS: Forty chronic kidney disease patients with fluid retention (average estimated glomerular filtration rate 29.2 ± 3.2 mL/min per 1.73 m2 ) were divided into the SGLT2 inhibitor dapagliflozin (DAPA), loop diuretic furosemide (FR) and vasopressin V2 receptor antagonist tolvaptan (TLV). The body fluid volume was measured on days 0 and 7 using a bioimpedance analysis device. RESULTS: In all three groups, body weight was significantly and similarly decreased, and urine volume numerically increased for 7 days. Bioimpedance analysis showed that the changes in intracellular water were similar, but that there were significant changes in the extracellular water (ECW) (DAPA -8.4 ± 1.7, FR -12.5 ± 1.3, TLV -7.4 ± 1.5%, P = 0.048). As a result, the change in the ratio of ECW to total body water in the DAPA group was significantly smaller than that in the FR group, but numerically larger than that in the TLV group (DAPA -1.5 ± 0.5, FR -3.6 ± 0.5, TLV -0.5 ± 0.4%, P < 0.001). CONCLUSION: Sodium-glucose cotransporter 2 inhibitor DAPA predominantly decreased the ECW with a mild increase in urine volume, but the change in the ECW/total body water was smaller than that in patients treated with FR, and larger than that in patients treated with TLV, suggesting that the effects of SGLT2 inhibitors on fluid distribution may differ from those of conventional diuretics.
Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas/uso terapéutico , Compuestos de Bencidrilo/uso terapéutico , Transferencias de Fluidos Corporales/efectos de los fármacos , Furosemida/uso terapéutico , Glucósidos/uso terapéutico , Insuficiencia Renal Crónica/tratamiento farmacológico , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Tolvaptán/uso terapéutico , Equilibrio Hidroelectrolítico/efectos de los fármacos , Desequilibrio Hidroelectrolítico/tratamiento farmacológico , Anciano , Composición Corporal/efectos de los fármacos , Femenino , Humanos , Masculino , Estudios Prospectivos , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Desequilibrio Hidroelectrolítico/diagnóstico , Desequilibrio Hidroelectrolítico/fisiopatologíaRESUMEN
BACKGROUND: In physically less fit patients and patients requiring repeated exams, adequate bowel preparation for colonoscopy remains problematic, particularly because patients need to drink large volumes of unpleasant-tasting fluids. A further concern is potential unwarranted fluid shifts. AIMS: This study aimed to compare the safety and burden of a small-volume sodium picosulphate/magnesium citrate preparation (SPS-MC) with a 2-l ascorbic-acid-enriched polyethylene glycol solution plus bisacodyl pretreatment (PEG-Asc+B). PATIENTS AND METHODS: Patients referred for colonoscopy were randomized to SPS-MC or PEG-Asc+B administered as a split-dose regimen. Patients received advice on the recommended 4-l SPS-MC and 2-l PEG-Asc+B fluid intake. Safety was assessed by blood sampling before and after the preparation and during a 30-day follow-up period. A questionnaire assessed tolerability and perceived burden of the preparation. RESULTS: A total of 341 patients underwent colonoscopy. Blood sampling showed a slight but significant decrease in sodium, chloride and osmolality and increase in magnesium in the SPS-MC group and a decrease in bicarbonate in the PEG-Asc+B group. Hyponatraemia and hypermagnesaemia without clinical signs were observed in 16 (14 SPS-MC) and 13 SPS-MC patients, respectively. Patients reported significantly fewer physical complaints and a significantly higher completion rate with SPS-MC. Patients receiving SPS-MC rated the intake as being easier and better tasting. In the event of a repeat colonoscopy, 59.7% of patients in the PEG-Asc+B and 93.6% of patients in the SPS-MC group would opt for the same preparation again. CONCLUSION: Despite electrolyte shifts, both SPS-MC and PEG-Asc+B appeared clinically safe. From a patient's perspective, a small-volume preparation formula such as SPS-MC is preferred, resulting in fewer physical complaints and greater ease of intake.
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Ácido Ascórbico/administración & dosificación , Bisacodilo/administración & dosificación , Catárticos/administración & dosificación , Citratos/administración & dosificación , Ácido Cítrico/administración & dosificación , Colon/efectos de los fármacos , Colonoscopía , Compuestos Organometálicos/administración & dosificación , Picolinas/administración & dosificación , Polietilenglicoles/administración & dosificación , Irrigación Terapéutica/métodos , Administración Oral , Adulto , Anciano , Ácido Ascórbico/efectos adversos , Biomarcadores/sangre , Bisacodilo/efectos adversos , Catárticos/efectos adversos , Citratos/efectos adversos , Ácido Cítrico/efectos adversos , Colon/patología , Esquema de Medicación , Combinación de Medicamentos , Femenino , Transferencias de Fluidos Corporales/efectos de los fármacos , Humanos , Hiponatremia/sangre , Hiponatremia/inducido químicamente , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Países Bajos , Compuestos Organometálicos/efectos adversos , Satisfacción del Paciente , Soluciones Farmacéuticas , Picolinas/efectos adversos , Polietilenglicoles/efectos adversos , Irrigación Terapéutica/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Equilibrio Hidroelectrolítico/efectos de los fármacosRESUMEN
Wheatley, Courtney M., Sarah E. Baker, Bryan J. Taylor, Manda L. Keller-Ross, Steven C. Chase, Alex R. Carlson, Robert J. Wentz, Eric M. Snyder, and Bruce D. Johnson. Influence of inhaled amiloride on lung fluid clearance in response to normobaric hypoxia in healthy individuals. High Alt Med Biol 18:343-354, 2017. AIM: To investigate the role of epithelial sodium channels (ENaC) on lung fluid clearance in response to normobaric hypoxia, 20 healthy subjects were exposed to 15 hours of hypoxia (fraction of inspired oxygen [FiO2] = 12.5%) on two randomized occasions: (1) inhaled amiloride (A) (1.5 mg/5 mL saline); and (2) inhaled saline placebo (P). Changes in lung fluid were assessed through chest computed tomography (CT) for lung tissue volume (TV), and the diffusion capacity of the lungs for carbon monoxide (DLCO) and nitric oxide (DLNO) for pulmonary capillary blood volume (VC). Extravascular lung water (EVLW) was derived as TV-VC and changes in the CT attenuation distribution histograms were reviewed. RESULTS: Normobaric hypoxia caused (1) a reduction in EVLW (change from baseline for A vs. P, -8.5% ± 3.8% vs. -7.9% ± 5.2%, p < 0.05), (2) an increase in VC (53.6% ± 28.9% vs. 53.9% ± 52.3%, p < 0.05), (3) a small increase in DLCO (9.6% ± 29.3% vs. 9.9% ± 23.9%, p > 0.05), and (4) CT attenuation distribution became more negative, leftward skewed, and kurtotic (p < 0.05). CONCLUSION: Acute normobaric hypoxia caused a reduction in lung fluid that was unaffected by ENaC inhibition through inhaled amiloride. Although possible amiloride-sensitive ENaC may not be necessary to maintain lung fluid balance in response to hypoxia, it is more probable that normobaric hypoxia promotes lung fluid clearance rather than accumulation for the majority of healthy individuals. The observed reduction in interstitial lung fluid means alveolar fluid clearance may not have been challenged.
Asunto(s)
Amilorida/administración & dosificación , Bloqueadores del Canal de Sodio Epitelial/administración & dosificación , Canales Epiteliales de Sodio/fisiología , Agua Pulmonar Extravascular/efectos de los fármacos , Pulmón/efectos de los fármacos , Administración por Inhalación , Adulto , Presión Atmosférica , Volumen Sanguíneo/efectos de los fármacos , Femenino , Transferencias de Fluidos Corporales/efectos de los fármacos , Voluntarios Sanos , Humanos , Hipoxia/fisiopatología , Pulmón/diagnóstico por imagen , Pulmón/fisiología , Masculino , Capacidad de Difusión Pulmonar/efectos de los fármacos , Distribución Aleatoria , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
We conducted a meta-analysis of pharmacogenomic substudies of three randomized trials conducted in patients with decompensated heart failure (HF) that were led by National Heart Lung and Blood Institute (NHLBI)-funded HF Network to test the hypothesis that candidate genes modulate net fluid loss and weight change in patients with decompensated HF treated with a furosemide-based diuretic regimen. Although none of the genetic variants previously shown to modulate the effects of loop diuretics in healthy individuals were associated with net fluid loss after 72 h of treatment, a set of rare variants in the APOL1 gene, which codes for apolipoprotein L1 (P=0.0005 in the random effects model), was associated with this end point. Moreover, a common variant in the multidrug resistance protein-4 coding gene (ABCC4, rs17268282) was associated with weight loss with furosemide use (P=0.0001). Our results suggest that both common and rare genetic variants modulate the response to a furosemide-based diuretic regimen in patients with decompensated HF.
Asunto(s)
Apolipoproteínas/genética , Furosemida/administración & dosificación , Insuficiencia Cardíaca/tratamiento farmacológico , Lipoproteínas HDL/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Variantes Farmacogenómicas , Polimorfismo de Nucleótido Simple , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/administración & dosificación , Administración Intravenosa , Anciano , Anciano de 80 o más Años , Apolipoproteína L1 , Ensayos Clínicos como Asunto , Femenino , Transferencias de Fluidos Corporales/efectos de los fármacos , Genotipo , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Farmacogenética , Fenotipo , Factores de Tiempo , Resultado del Tratamiento , Equilibrio Hidroelectrolítico/efectos de los fármacosRESUMEN
OBJECTIVES: Obstructive sleep apnea (OSA) is highly prevalent in patients with fluid-retaining conditions. Using bioimpedance measurements, previous studies have shown that the greater the amount of fluid redistributed from the legs to the neck overnight, the greater the severity of OSA. Our objective was to investigate factors that predispose the development or worsening of OSA in response to experimental fluid overload. METHODS: Fifteen normotensive and non-obese adult men with and without OSA underwent polysomnography (PSG) during which normal saline was infused intravenously at a minimal rate to keep the vein open (control) or as a bolus of 22 ml/kg body weight (approximately 2 L) in a random order and crossed over after a week. RESULTS AND CONCLUSIONS: Before and after sleep, neck circumference and bioimpedance were measured to calculate neck resistance, reactance, phase angle, and fluid volume. Subjects who experienced more than a twofold increase in apnea-hypopnea index (AHI) or obstructive AHI from control to intervention and had an AHI>10 during intervention were considered susceptible to the development or worsening of OSA. Baseline neck circumference and phase angle before saline infusion were independently associated with increased susceptibility to developing or worsening OSA in response to saline infusion. In non-obese men, a larger neck circumference and bioimpedance phase angle of the neck, which may be associated with larger pharyngeal tissue content, is associated with increased susceptibility for worsening of OSA in response to fluid overloading.
Asunto(s)
Transferencias de Fluidos Corporales/fisiología , Apnea Obstructiva del Sueño/etiología , Adulto , Estudios Cruzados , Transferencias de Fluidos Corporales/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Cuello , Polisomnografía , Apnea Obstructiva del Sueño/fisiopatología , Cloruro de Sodio/farmacologíaRESUMEN
UNLABELLED: The leading role in glaucoma treatment is now played by prostaglandin analogues (PGAs), whose point of application is the uveoscleral outflow of aqueous humor. Quantitative evaluation of the latter is, however, a problem yet unsolved. AIM: To assess the clinical applicability of a new method for quantitative evaluation of the uveoscleral outflow in human eyes, which is meant to help with optimization of glaucoma therapy. MATERIAL AND METHODS: Patients with early (n=33) and advanced (n=30) primary open-angle glaucoma (POAG) were enrolled. Besides the routine ophthalmic examination, all patients had their uveoscleral outflow quantified with our method. Basing on these findings, we have analyzed the effect of different hypotensive eye drops, namely, betaxolol 0.5% (selective beta-1-blocker), brinzolamid 1% (carbonic anhydrase inhibitor), travoprost 0.004% (prostaglandin analogue) and travoprost 0.004%/timolol 0.5% fixed combination (TTFC; prostaglandin analogue plus non-selective beta-blocker). RESULTS: In early POAG, the uveoscleral outflow facility (Cfu) without treatment was 0.06±0.06, after betaxolol 0.5% as well as brinzolamid 1% use - 0.05±0.03, while after travoprost 0.004% and FCTT use - 0.10±0.06 and 0.08±0.05 correspondingly. In advanced POAG, Cfu was 0.04±0.03 without treatment, 0.06±0.04 - after betaxolol 0.5% or brinzolamid 1% use, 0.1±0.05 - after travoprost 0.004% use, and 0.1±0.04 - after FCTT use. CONCLUSION: Quantitative evaluation of the uveoscleral outflow with the new method that has not only been justified, but also clinically tested, provides an opportunity to optimize POAG treatment.
Asunto(s)
Antagonistas Adrenérgicos beta/administración & dosificación , Transferencias de Fluidos Corporales/efectos de los fármacos , Glaucoma de Ángulo Abierto , Prostaglandinas Sintéticas/administración & dosificación , Humor Acuoso/diagnóstico por imagen , Femenino , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Hidrodinámica , Masculino , Persona de Mediana Edad , Soluciones Oftálmicas/administración & dosificación , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Postoperative fluid overload following cardiac surgery is associated with increased morbidity and mortality. Unlike loop diuretics, tolvaptan (TLV) promotes aquaretic effect. Relatively little has been documented regarding the efficacy of TLV after cardiac surgery. The aim of the study was to investigate the effectiveness and safety of tolvaptan for the management of immediately postoperative fluid retention following cardiac surgery. METHODS: Between January to May 2014, patients undergoing cardiac surgery were randomly assigned to control or TLV group immediately after cardiac surgery. In control group, patients received 20mg of furosemide and 25mg of spironolactone as conventional diuretics. In the TLV group, 7.5mg of TLV was administered in combination with conventional diuretics. RESULTS: TLV use was associated with increased urine output from postoperative day 1 to 3.Body weight reduction in the TLV group was significantly greater than the control group from postoperative day 2 to 4, and serum creatinine levels decreased to below preoperative values in the TLV group. CONCLUSIONS: The combination of tolvaptan with conventional diuretics increases urine output without renal dysfunction and can be effective for postoperative fluid management and appropriate body weight reduction.
Asunto(s)
Benzazepinas , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Transferencias de Fluidos Corporales/efectos de los fármacos , Furosemida , Complicaciones Posoperatorias , Espironolactona , Anciano , Antagonistas de los Receptores de Hormonas Antidiuréticas/administración & dosificación , Antagonistas de los Receptores de Hormonas Antidiuréticas/efectos adversos , Benzazepinas/administración & dosificación , Benzazepinas/efectos adversos , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Procedimientos Quirúrgicos Cardíacos/métodos , Diuréticos/administración & dosificación , Diuréticos/efectos adversos , Monitoreo de Drogas , Quimioterapia Combinada/métodos , Femenino , Furosemida/administración & dosificación , Furosemida/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Espironolactona/administración & dosificación , Espironolactona/efectos adversos , Tolvaptán , Resultado del Tratamiento , Urinálisis/métodosRESUMEN
Fluid shift from the legs and into the neck during sleep has been shown to increase tissue pressure around the upper airway and increase sleep apnea severity. Recently, acute fluid overload via saline infusion during sleep was shown to increase sleep apnea severity in an older men (≥ 40 years of age) but not the younger men (<;40 years of age). The purpose of this study was to estimate the changes in the autonomic nervous system response to saline infusion in the younger and older men using well studied time- and frequency domain heart rate variability metrics (HRV). Eighteen healthy men (10 in the younger group and 8 in the older group) slept for up to 3 hours during the day while ≈ 2L of saline was intravenously injected during sleep. An electrocardiogram was collected continuously during the sleep period. Two five minute segments of stage 1 or 2 sleep were selected for analysis of HRV: one before saline infusion and one after completion of saline infusion. Time- and frequency domain metrics of HRV were used to characterize autonomic nervous system response. Results generally showed increased HRV as measured by time-domain statistical measures in the younger men after saline infusion. In the frequency domain, the change in high frequency power from pre- to post-saline infusion was significantly greater in the younger compared to the older men. In addition, there was a borderline significant trend showing an increase in HF power from pre- to post-saline infusion in the younger, but not the older men. These results suggest that only in the younger men and not the older men, parasympathetic nervous activity increased in response to acute fluid overload. This might be one of the mechanisms that increased the severity of OSA in older and not the younger men.
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Transferencias de Fluidos Corporales , Frecuencia Cardíaca , Sueño/fisiología , Cloruro de Sodio , Adulto , Sistema Nervioso Autónomo/fisiología , Electrocardiografía , Transferencias de Fluidos Corporales/efectos de los fármacos , Transferencias de Fluidos Corporales/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Cloruro de Sodio/administración & dosificación , Cloruro de Sodio/farmacología , Adulto JovenRESUMEN
STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is commoner in patients with fluid-retaining states than in those without fluid retention, in men than in women, and worsens with aging. In men, OSA severity is related to the amount of fluid shifting out of the legs overnight, but a cause-effect relationship is not established. Our objective was to test the hypothesis that mimicking fluid overload during sleep would increase severity of OSA more in older (≥ 40 years) than in younger men (< 40 years). DESIGN: Randomized, single-blind, double crossover study. SETTING: Research sleep laboratory. PATIENTS OR PARTICIPANTS: Seven older and 10 younger men with non-severe or no sleep apnea, matched for body mass index. INTERVENTIONS: During the control arm, normal saline was infused to keep the vein open. During intervention, subjects received an intravenous bolus of normal saline (22 mL/kg body weight) after sleep onset while they were wearing compression stockings to prevent fluid accumulation in the legs. MEASUREMENTS AND RESULTS: Compared to younger men, infusion of similar amounts of saline in older men caused a greater increase in neck circumference (P < 0.05) and in the AHI (32.2 ± 22.1 vs. 2.2 ± 7.1, P = 0.002). CONCLUSIONS: Older men are more susceptible to the adverse effects of intravenous fluid loading on obstructive sleep apnea severity than younger men. This may be due to age-related differences in the amount of fluid accumulating in the neck or upper airway collapsibility in response to intravenous fluid loading. These possibilities remain to be tested in future studies.
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Envejecimiento/fisiología , Transferencias de Fluidos Corporales/efectos de los fármacos , Apnea Obstructiva del Sueño/fisiopatología , Sueño/efectos de los fármacos , Cloruro de Sodio/administración & dosificación , Cloruro de Sodio/farmacología , Administración Intravenosa , Adulto , Índice de Masa Corporal , Estudios Cruzados , Transferencias de Fluidos Corporales/fisiología , Humanos , Pierna/fisiología , Masculino , Persona de Mediana Edad , Cuello/anatomía & histología , Polisomnografía , Método Simple Ciego , Sueño/fisiología , Medias de CompresiónRESUMEN
OBJECTIVE: The purpose of this study was to examine the isovolumetric distribution kinetics of crystalloid fluid during cardiopulmonary bypass. METHODS: Ten patients undergoing coronary artery bypass grafting participated in this prospective observational study. The blood hemoglobin and the serum albumin and sodium concentrations were measured repeatedly during the distribution of priming solution (Ringer's acetate 1470 ml and mannitol 15% 200 ml) and initial cardioplegia. The rate of crystalloid fluid distribution was calculated based on 3-min Hb changes. The preoperative blood volume was extrapolated from the marked hemodilution occurring during the onset of cardiopulmonary bypass. Clinicaltrials.gov: NCT01115166. RESULTS: The distribution half-time of Ringer's acetate averaged 8 minutes, corresponding to a transcapillary escape rate of 0.38 ml/kg/min. The intravascular albumin mass increased by 5.4% according to mass balance calculations. The preoperative blood volume, as extrapolated from the drop in hemoglobin concentration by 32% (mean) at the beginning of cardiopulmonary bypass, was 0.6-1.2 L less than that estimated by anthropometric methods (p<0.02). The mass balance of sodium indicated a translocation from the intracellular to the extracellular fluid space in 8 of the 10 patients, with a median volume of 236 ml. CONCLUSIONS: The distribution half-time of Ringer's solution during isovolumetric cardiopulmonary bypass was 8 minutes, which is the same as for crystalloid fluid infusions in healthy subjects. The intravascular albumin mass increased. Most patients were hypovolemic prior to the start of anesthesia. Intracellular edema did not occur.
Asunto(s)
Volumen Sanguíneo/fisiología , Puente Cardiopulmonar , Soluciones Isotónicas/farmacocinética , Anciano , Anciano de 80 o más Años , Volumen Sanguíneo/efectos de los fármacos , Edema Encefálico/etiología , Puente de Arteria Coronaria , Soluciones Cristaloides , Espacio Extracelular/metabolismo , Femenino , Transferencias de Fluidos Corporales/efectos de los fármacos , Transferencias de Fluidos Corporales/fisiología , Hemoglobinas/análisis , Humanos , Masculino , Manitol/farmacología , Persona de Mediana Edad , Estudios Prospectivos , Albúmina Sérica/análisis , Sodio/sangre , Sodio/orina , Equilibrio Hidroelectrolítico/fisiologíaRESUMEN
OBJECTIVE: The purpose of this study was to examine the isovolumetric distribution kinetics of crystalloid fluid during cardiopulmonary bypass. METHODS: Ten patients undergoing coronary artery bypass grafting participated in this prospective observational study. The blood hemoglobin and the serum albumin and sodium concentrations were measured repeatedly during the distribution of priming solution (Ringer's acetate 1470 ml and mannitol 15% 200 ml) and initial cardioplegia. The rate of crystalloid fluid distribution was calculated based on 3-min Hb changes. The preoperative blood volume was extrapolated from the marked hemodilution occurring during the onset of cardiopulmonary bypass. Clinicaltrials.gov: NCT01115166. RESULTS: The distribution half-time of Ringer's acetate averaged 8 minutes, corresponding to a transcapillary escape rate of 0.38 ml/kg/min. The intravascular albumin mass increased by 5.4% according to mass balance calculations. The preoperative blood volume, as extrapolated from the drop in hemoglobin concentration by 32% (mean) at the beginning of cardiopulmonary bypass, was 0.6-1.2 L less than that estimated by anthropometric methods (p<0.02). The mass balance of sodium indicated a translocation from the intracellular to the extracellular fluid space in 8 of the 10 patients, with a median volume of 236 ml. CONCLUSIONS: The distribution half-time of Ringer's solution during isovolumetric cardiopulmonary bypass was 8 minutes, which is the same as for crystalloid fluid infusions in healthy subjects. The intravascular albumin mass increased. Most patients were hypovolemic prior to the start of anesthesia. Intracellular edema did not occur. .