[Comparative analysis of bleed volume with visual technique]. / Análisis comparativo de volumen de sangrado mediante técnica visual.

Background: Blood loss estimation in a surgery is made by anesthesiologists by means of visual technique, which is not reliable because it can change depending on the judgement of every person, or his/her work experience, which is why it is considered something subjective. Therefore, the results obtained could lead to make mistakes with the exact amount of bleeding, mismanaging unnecessary hemoderived transfusions or administering unnecessary drugs. Objective: To compare the blood volume and its visual calculation between Anesthesiology residents and anesthesiologists. Material and methods: Prolective cross-sectional study which included 85 Anesthesiology residents and anesthesiologists. Diverse scenarios of bleeding were set, divided into gauze pads, compresses and jars, and each participant was asked to answer the poll. Results: There is no significant difference in the estimate of bleeding between the estimation made by residents and anesthesiologists. Conclusions: The grade of studies or experience is not significant for the exact estimation of bleeding with visual technique.

Introducción: la estimación de sangrado en las cirugías se realiza por medio de la técnica de cálculo visual, que es llevada a cabo por parte del servicio de anestesiología. Se trata de una técnica poco confiable, que puede variar dependiendo del juicio de cada persona y de su experiencia laboral, por lo que es considerada algo subjetivo. Por lo tanto, los datos arrojados hacen que se cometan errores en la cantidad exacta del sangrado y llevan a transfusiones de paquetes globulares o a la administración probablemente innecesaria de medicamentos. Objetivo: comparar la cantidad de un volumen de sangrado determinado y su cálculo visual realizada por residentes de Anestesiología y anestesiólogos. Material y métodos: estudio transversal prolectivo en el cual se incluyeron 85 médicos residentes de Anestesiología y anestesiólogos. Se dispusieron diversos escenarios con sangrado, los cuales se dividieron en gasas, compresas y frascos, y se le pidió a cada médico que contestara la encuesta correspondiente según su criterio. Resultados: de acuerdo con los resultados, no hay diferencia significativa en la estimación realizada del sangrado entre residentes y anestesiólogos para las muestras estudiadas. Conclusiones: el grado de estudios o experiencia no es significativo para la exacta estimación de sangrado con técnica visual.

Relative cerebral blood volume as response predictor in the treatment of recurrent glioblastoma with anti-angiogenic therapy.

BACKGROUND: Glioblastoma is one of the most common brain tumors in adult populations, usually carrying a poor prognosis. While several studies have researched the impact of anti-angiogenic therapies, especially anti-VEFG treatments in glioblastoma, few have attempted to assess its progress using imaging studies. PURPOSE: We attempted to analyze whether relative cerebral blood volume (rCBV) from dynamic susceptibility-weighted contrast-enhanced MRI (DSC-MRI) could predict response in patients with glioblastoma undergoing Bevacizumab (BVZ) treatment. METHODS: We performed a retrospective study evaluating patients with recurrent glioblastoma receiving anti-angiogenic therapy with BVZ between 2012 and 2017 in our institution. Patients were scheduled for routine MRIs at baseline and first-month follow-up visits. Studies were processed for DSC-MRI, cT1, and FLAIR images, from which relative cerebral blood volume measurements were obtained. We assessed patient response using the Response Assessment in Neuro-Oncology (RANO) working group criteria and overall survival. RESULTS: 40 patients were included in the study and were classified as Bevacizumab responders and non-responders. The average rCBV before treatment was 4.5 for both groups, and average rCBV was 2.5 for responders and 5.4 for non-responders. ROC curve set a cutoff point of 3.7 for rCBV predictive of response to BVZ. Cox Multivariate analysis only showed rCBV as a predictive factor of OS. CONCLUSION: A statistically significant difference was found in rCBV between patients who responded and those who did not respond to BVZ treatment. rCBV may be a low-cost and effective marker to assess response to Bevacizumab treatment in GBM.

Short exposure to high salt in drinking solution leads to a cardiovascular phenotype of hypertension without changes in the blood volume of rats.

NEW FINDINGS: What is the central question of this study? Is the cardiovascular phenotype of high blood pressure observed in rats salt loaded with 2% NaCl in drinking solution a blood volume-dependent hypertension? What is the main finding and its importance? Animals exposed to 2% NaCl drinking solution develop hypertension, with dominance of sympathetic outflow and high [Na+ ] in the cerebrospinal fluid, but without changes in the blood volume. The phenotype of salt-dependent hypertension might be related to accumulation of [Na+ ] in the cerebrospinal fluid, which makes it an interesting animal model in which to study the neuronal pathways involved in control of the circulation in osmotic challenge conditions. ABSTRACT: Evidence suggests that hypertension induced by high salt intake is correlated with an autonomic imbalance that favours sympathetic hyperactivity and an increase in vascular resistance, indicating a neurogenic component to this pathology. Although there are several animal models in which to study salt-induced hypertension with prolonged exposure to a high-sodium diet, here we sought to investigate whether the increase in arterial blood pressure of rats subjected to a short exposure to high salt, with 2% NaCl drinking solution instead of water, relies on changes in the circulating blood volume. Male Wistar rats were divided randomly into three groups: euhydrated (EU, n = 10), salt loaded (SL, n = 13) and water deprived (WD, n = 6). The SL rats exhibited a significant increase in mean arterial blood pressure, with a large low-frequency component of systolic arterial blood pressure variability, when compared with the EU group. Circulating blood volume did not differ between SL and EU rats, but it was lower in WD rats. Compared with EU rats, the [Na+ ] in cerebrospinal fluid was higher in SL rats and similar in magnitude to the WD rats. Plasma [Na+ ] did not differ between SL and EU rats, but it was higher in WD rats. Collectively, our data suggest that the hypertension induced by a short exposure to high salt intake closely resembles a neurogenic mechanism, but not a blood volume-dependent mechanism, with cumulative [Na+ ] in the cerebrospinal fluid that could be associated with changes in the neurochemistry of autonomic nuclei, which are highly susceptible to osmotic stress related to high salt consumption.

Quantitative analysis of pulmonary perfusion with dual-energy CT angiography: comparison of two quantification methods in patients with pulmonary embolism.

The study aimed to evaluate a quantification method of pulmonary perfusion with Dual-Energy CT Angiography (DE-CTA) normalized by lung density in the prediction of outcome in acute pulmonary embolism (PE). In this prospective study with CTA scans acquired with different breathing protocols, two perfusion parameters were calculated: %PBV (relative value of PBV, expressed per unit volume) and PBVm (PBV normalized by lung density, expressed per unit mass). DE-CTA parameters were correlated with simplified pulmonary embolism severity index (sPESI) and with outcome groups, alone and in combinationwith tomographic right-to-left ventricular ratios (RV/LV). PBVm showed significant correlation with sPESI. PBVm presented higher accuracy than %PBV In the prediction of ICU admission or death in patients with PE, with the best performance when combined with RV/LV volumetric ratio.

Effect of hypobaric hypoxia on hematological parameters related to oxygen transport, blood volume and oxygen consumption in adolescent endurance-training athletes.

Objective: To analyze the effect of altitude on hematological and cardiorespiratory variables in adolescent athletes participating in aerobic disciplines. Methods: 21 females and 89 males participated in the study. All were adolescent elite athletes engaged in endurance sports (skating, running and cycling) belonging to two groups: permanent residents in either low altitude (LA, 966 m) or moderate altitude (MA, 2640 m). Hematocrit (Hct), hemoglobin concentration ([Hb]), total hemoglobin mass (Hbt), blood, plasma and erythrocyte volumes (BV, PV and EV), VO2peak and other cardiorespiratory parameters were evaluated. Results: Sex differences were evident both in LA and HA skating practitioners, the males having higher significant values than the females in oxygen transport-related hematological parameters and VO2peak. The effect of altitude residence was also observed in Hct, [Hb], Hbt and EV with increased (14%-18%) values in the hematological parameters and higher EV (5%-24%). These results matched the significantly higher values of VO2peak measured in MA residents. However, BV and PV did not show differences between LA and MA residents in any case. Sports discipline influenced neither the hematological variables nor most of the cardiorespiratory parameters. Conclusions: LA and MA adolescent skaters showed sex differences in hematological variables. Endurance-trained male adolescent residents at MA had an increased erythropoietic response and a higher VO2peak compared to their counterparts residing and training at LA. These responses are similar in the three aerobic sports studied, indicating that the variables described are highly sensitive to hypoxia irrespective of the sports discipline.

Sex Modulates Cardiovascular Effects of Icodextrin-Based Peritoneal Dialysis Solutions.

Background/Aims: Some previous observations have noted that after six months of peritoneal dialysis (PD) treatment with icodextrin solutions, blood pressure (BP) and NT-proBNP tend to return to baseline values. This may be due to accumulation of icodextrin products that exert a colloid osmotic effect, which drives water into the bloodstream, causing the rise in blood pressure. Since icodextrin is metabolized by α-Amylase and its gene copies are lower in females than in males, we hypothesized icodextrin metabolites reach higher concentrations in females and that cardiovascular effects of icodextrin are influenced by sex. Methods: Secondary analysis of a RCT comparing factors influencing fluid balance control in diabetic PD patients with high or high average peritoneal transport receiving icodextrin (n = 30) or glucose (n = 29) PD solutions. Serum icodextrin metabolites, osmolality, body composition and Inferior Vena Cava (IVC) diameter were measured at baseline, and at 6 and 12 months of follow-up. Results: After six months of treatment, icodextrin metabolites showed higher levels in females than in males, particularly G5-7 and >G7, serum osmolality was lower in females. In spite of reduction in total and extracellular body water, ultrafiltration (UF) was lower and IVC diameter and BP increased in females, suggesting increment of blood volume. Conclusion: Females undergoing PD present with higher levels of icodextrin metabolites in serum that may exert an increased colloid-osmotic pressure followed by less UF volumes and increment in blood volume and blood pressure. Whether this could be due to the lesser number of α-Amylase gene copies described in diabetic females deserves further investigation.

Lobar pulmonary perfusion quantification with dual-energy CT angiography: Interlobar variability and relationship with regional clot burden in pulmonary embolism.

Purpose: Semi-automated lobar segmentation tools enable an anatomical assessment of regional pulmonary perfusion with Dual-Energy CTA (DE-CTA). We aimed to quantify lobar pulmonary perfusion with DE-CTA, analyze the perfusion distribution among the pulmonary lobes in subjects without cardiopulmonary diseases and assess the correlation between lobar perfusion and regional endoluminal clots in patients with acute pulmonary embolism (PE). Methods: We evaluated 151 consecutive subjects with suspected PE and without cardiopulmonary comorbidities. DE-CTA derived perfused blood volume (PBV) of each pulmonary lobe was measured applying a semi-automated lobar segmentation technique. In patients with PE, blood clot location was assessed, and CT-based vascular obstruction index of each lobe (CTOIlobe) was calculated and classified into three groups: CTOIlobe= 0, low CTOIlobe (1-50%) and high CTOIlobe (>50%). Results: Among patients without PE (103/151, 68.2%), median lobar PBV was 13.7% (IQR 10.2-18.0%); the right middle lobe presented lower PBV when compared to all the other lobes (p < .001). In patients with PE (48/151, 31.8%), lobar PBV was 12.6% (IQR 9.6-15.7%), 13.7% (IQR 10.1-16.7%) and 6.5% (IQR 5.1-10.2%) in the lobes with CTOIlobe= 0, low CTOIlobe and high CTOIlobe scores, respectively, with a significantly decreased PBV in the lobes with high CTOIlobe score (p < .001). ROC analysis of lobar PBV for prediction of high CTOIlobe score revealed AUC of 0.847 (95%CI 0.785-0.908). Conclusion: Pulmonary perfusion was heterogeneously distributed along the pulmonary lobes in patients without cardiopulmonary diseases. In patients with PE, the lobes with high vascular obstruction score (CTOIlobe> 50%) presented a decreased lobar perfusion.

Turmeric root extract supplementation improves pre-frontal cortex oxygenation and blood volume in older males and females: a randomised cross-over, placebo-controlled study.

Ageing is associated with endothelial dysfunction and reduced cerebral blood flow and oxygenation. The present study aimed to investigate whether turmeric supplementation could improve cerebral oxygenation and blood volume during brain activation via dynamic handgrip exercise in older males and females. Twelve older males and females were studied using a double-blind, placebo-controlled, cross-over design. Participants ingested turmeric root extract or placebo. Heart rate and blood pressure were measured before and 2 hours after supplementation. Afterward, the exercise protocol was started, and cerebral oxygenation and blood volume were evaluated. During exercise, changes in cerebral oxygenation were higher after turmeric extract supplementation, as was blood volume compared to placebo. Changes in heart rate, systolic blood pressure, and diastolic blood pressure were not significant. The current findings indicate the potential for curcumin as an intervention for improving cerebral oxygenation and blood volume changes in older males and females. Clinical trial registry: NCT04119752.

Quantification of testosterone-dependent erythropoiesis during male puberty.

NEW FINDINGS: What is the central question of this study? To what extent does testosterone influence haemoglobin formation during male puberty? What is the main finding and its importance? In boys, testosterone might be responsible for about 65% of the increase in haemoglobin mass during puberty. The underlying mechanisms are assumed to be twofold: (i) indirectly, mediated by the increase in lean body mass, and (ii) directly by immediate testosterone effects on erythropoiesis. Thereby, an increase in testosterone of 1 ng/ml is associated with an increase in haemoglobin mass of ∼65 g. These processes are likely to determine endurance performance in adulthood. ABSTRACT: The amount of haemoglobin during puberty is related to endurance performance in adulthood. During male puberty, testosterone stimulates erythropoiesis and could therefore be used as a marker for later endurance performance. This cross-sectional study aimed to determine the relationship between serum testosterone concentration and haemoglobin mass (Hbmass) in both male and female children and adolescents and to evaluate the possible influences of altitude and training. Three-hundred and thirteen differentially trained boys and girls aged from 9 to 18 years and living at altitudes of 1000 and 2600 m above sea level entered the study. The stage of sexual maturation was determined according to the classification of Tanner. Testosterone was measured by ELISA. Hbmass was determined by CO-rebreathing. Haemoglobin concentration did not change during maturation in girls and was 11% higher during puberty in boys, while Hbmass was elevated by 33% in Tanner stage V compared to stage II in girls (498 ± 77 vs. 373 ± 88 g) and by 95% in boys (832 ± 143 vs. 428 ± 95 g). This difference can most likely be attributed to indirect testosterone influences through an increase in lean body mass (LBM) and to direct testosterone effects on erythropoiesis, which increase the Hbmass by ∼65 g per 1 ng/ml. Altitude and training statuses were not associated with testosterone, but with an increase in Hbmass (altitude by 1.1 g/kg LBM, training by 0.8 g/kg LBM). Changes in Hbmass are closely related to testosterone levels during male puberty. Further studies will show whether testosterone and Hbmass during childhood and adolescence can be used as diagnostic tools for endurance talents.

Low-Intensity Intradialytic Exercise Attenuates the Relative Blood Volume Drop Due to Intravascular Volume Loss during Hemodiafiltration.

INTRODUCTION: Patients in hemodiafiltration (HDF) eliminate volume overload by ultrafiltration. Vascular volume loss is among the main mechanisms contributing to adverse events such as intradialytic hypotension. Here, we hypothesize that the intradialytic exercise (IDEX) is an intervention that could improve the acute response of physiological mechanisms involved during vascular volume loss. To test this hypothesis, we evaluated the hemodynamic response to mild aerobic exercise during HDF. METHODS: Nineteen end-stage renal disease (ESRD) patients (11 women: 40 ± 10.8 years old, and 8 men: 42 ± 21 years old) receiving HDF thrice a week, with 6 months of previous physical conditioning, participated in this study. Three HDF sessions were scheduled for each patient: 1 resting in supine position, 1 resting in sitting position, and 1 doing aerobic exercise. The first 2 sessions were taken as control. The ultrafiltration rate was set to 800 mL/h in each session. The hemodynamic response was monitored through the relative blood volume (RBV), and cardiovascular variables measured noninvasively by photoplethysmography. Adequacy variables such as Kt/V and percentage reduction of urate, urea, creatinine (Cr), and phosphate were also monitored. FINDINGS: The decrease rate of the RBV was smaller in the session with IDEX compared to the sessions with no exercise. No differences were found neither in the cardiovascular variables nor in the adequacy variables among the 3 sessions. There were no hypotension events during the session with exercise, and 8 events during the sessions without exercise (p = 0.002). DISCUSSION: Mild exercise during HDF decreased the RBV drop and was associated with less hypotension events. The lack of differences in the hemodynamic variables suggests an adequate acute response of cardiovascular compensation variables to intradialytic hypovolemia.

Prehospital Damage Control: The Management of Volume, Temperature… and Bleeding! / Control de Daños Prehospitalario: ¡Para Los Cristaloides, Para La Hipotermia Y…! ¡Para El Sangrado!

Abstract Damage control resuscitation should be initiated as soon as possible after a trauma event to avoid metabolic decompensation and high mortality rates. The aim of this article is to assess the position of the Trauma and Emergency Surgery Group (CTE) from Cali, Colombia regarding prehospital care, and to present our experience in the implementation of the "Stop the Bleed" initiative within Latin America. Prehospital care is phase 0 of damage control resuscitation. Prehospital damage control must follow the guidelines proposed by the "Stop the Bleed" initiative. We identified that prehospital personnel have a better perception of hemostatic techniques such as tourniquet use than the hospital providers. The use of tourniquets is recommended as a measure to control bleeding. Fluid management should be initiated using low volume crystalloids, ideally 250 cc boluses, maintaining the principle of permissive hypotension with a systolic blood pressure range between 80- and 90-mm Hg. Hypothermia must be management using warmed blankets or the administration of intravenous fluids warmed prior to infusion. However, these prehospital measures should not delay the transfer time of a patient from the scene to the hospital. To conclude, prehospital damage control measures are the first steps in the control of bleeding and the initiation of hemostatic resuscitation in the traumatically injured patient. Early interventions without increasing the transfer time to a hospital are the keys to increase survival rate of severe trauma patients.

Resumen La resucitación en el control de daños debe iniciarse lo más rápido posible después de presentado el evento traumático para evitar descompensación metabólica y aumento de la mortalidad. El objetivo de este artículo es sustentar nuestro enfoque respecto a la atención prehospitalaria y presentar nuestra experiencia en la implementación de la iniciativa "Stop the Bleed" en Latinoamérica. La atención prehospitalaria es la fase Cero de la resucitación del control de daños. Por medio de la implementación de la iniciativa "Stop the Bleed" se identificó que el personal prehospitalario tiene una mejor percepción sobre el uso de técnicas hemostáticas como el torniquete que el personal hospitalario. Se recomienda el uso de torniquetes como medida de control de sangrado en extremidades. El manejo de líquidos debe realizarse usando cristaloides a bajos volúmenes, con bolos de 250 mL para cumplir el principio de la hipotensión permisiva con un rango entre 80 y 90 mm Hg de presión arterial sistólica. Se deben realizar medidas para evitar la hipotermia como el uso de sábanas térmicas o paso de líquidos calientes. Estas medidas no deben retrasar en ningún momento el tiempo de traslado para recibir la atención hospitalaria. En conclusión, la atención prehospitalaria es el paso inicial para garantizar las primeras medidas de control de sangrado y de resucitación hemostática de los pacientes. Realizar intervenciones tempranas sin acortar el tiempo de traslado a la atención hospitalaria son las claves para aumentar la tasa de supervivencia.

Quantitative Imaging Parameters of Contrast-Enhanced Micro-Computed Tomography Correlate with Angiogenesis and Necrosis in a Subcutaneous C6 Glioma Model.

The aim of this work was to systematically obtain quantitative imaging parameters with static and dynamic contrast-enhanced (CE) X-ray imaging techniques and to evaluate their correlation with histological biomarkers of angiogenesis in a subcutaneous C6 glioma model. Enhancement (E), iodine concentration (CI), and relative blood volume (rBV) were quantified from single- and dual-energy (SE and DE, respectively) micro-computed tomography (micro-CT) images, while rBV and volume transfer constant (Ktrans) were quantified from dynamic contrast-enhanced (DCE) planar images. CI and rBV allowed a better discernment of tumor regions from muscle than E in SE and DE images, while no significant differences were found for rBV and Ktrans in DCE images. An agreement was found in rBV for muscle quantified with the different imaging protocols, and in CI and E quantified with SE and DE protocols. Significant strong correlations (Pearson r > 0.7, p < 0.05) were found between a set of imaging parameters in SE images and histological biomarkers: E and CI in tumor periphery were associated with microvessel density (MVD) and necrosis, E and CI in the complete tumor with MVD, and rBV in the tumor periphery with MVD. In conclusion, quantitative imaging parameters obtained in SE micro-CT images could be used to characterize angiogenesis and necrosis in the subcutaneous C6 glioma model.

Prehospital Damage Control: The Management of Volume, Temperature and Bleeding!

Damage control resuscitation should be initiated as soon as possible after a trauma event to avoid metabolic decompensation and high mortality rates. The aim of this article is to assess the position of the Trauma and Emergency Surgery Group (CTE) from Cali, Colombia regarding prehospital care, and to present our experience in the implementation of the "Stop the Bleed" initiative within Latin America. Prehospital care is phase 0 of damage control resuscitation. Prehospital damage control must follow the guidelines proposed by the "Stop the Bleed" initiative. We identified that prehospital personnel have a better perception of hemostatic techniques such as tourniquet use than the hospital providers. The use of tourniquets is recommended as a measure to control bleeding. Fluid management should be initiated using low volume crystalloids, ideally 250 cc boluses, maintaining the principle of permissive hypotension with a systolic blood pressure range between 80- and 90-mm Hg. Hypothermia must be management using warmed blankets or the administration of intravenous fluids warmed prior to infusion. However, these prehospital measures should not delay the transfer time of a patient from the scene to the hospital. To conclude, prehospital damage control measures are the first steps in the control of bleeding and the initiation of hemostatic resuscitation in the traumatically injured patient. Early interventions without increasing the transfer time to a hospital are the keys to increase survival rate of severe trauma patients.

La resucitación en el control de daños debe iniciarse lo más rápido posible después de presentado el evento traumático para evitar descompensación metabólica y aumento de la mortalidad. El objetivo de este artículo es sustentar nuestro enfoque respecto a la atención prehospitalaria y presentar nuestra experiencia en la implementación de la iniciativa "Stop the Bleed" en Latinoamérica. La atención prehospitalaria es la fase Cero de la resucitación del control de daños. Por medio de la implementación de la iniciativa "Stop the Bleed" se identificó que el personal prehospitalario tiene una mejor percepción sobre el uso de técnicas hemostáticas como el torniquete que el personal hospitalario. Se recomienda el uso de torniquetes como medida de control de sangrado en extremidades. El manejo de líquidos debe realizarse usando cristaloides a bajos volúmenes, con bolos de 250 mL para cumplir el principio de la hipotensión permisiva con un rango entre 80 y 90 mm Hg de presión arterial sistólica. Se deben realizar medidas para evitar la hipotermia como el uso de sábanas térmicas o paso de líquidos calientes. Estas medidas no deben retrasar en ningún momento el tiempo de traslado para recibir la atención hospitalaria. En conclusión, la atención prehospitalaria es el paso inicial para garantizar las primeras medidas de control de sangrado y de resucitación hemostática de los pacientes. Realizar intervenciones tempranas sin acortar el tiempo de traslado a la atención hospitalaria son las claves para aumentar la tasa de supervivencia.

Hypotonic enteral electrolyte solutions administered by nasoesophageal tube in continuous flow in dogs dehydrated by water restriction: Part 1 / Soluções eletrolíticas enterais hipotônicas administradas por sonda nasoesofágica em fluxo contínuo em cães desidratados por restrição hídrica: Parte 1

The present study assessed and compared the effects of hypotonic enteral electrolyte solutions administered by nasoesophageal tube in continuous flow in dogs submitted to water restriction on packed cell volume; total serum protein and serum osmolarity concentrations; blood volume; plasma glucose and lactate levels; blood gas analysis, anion gap, and strong ion difference. Six adult dogs were used (four males and two females). All animals were submitted to both proposed treatments in a crossover design 6×2. The treatments were as follows: ESmalt consisting of 5g sodium chloride, 1g potassium chloride, 1g calcium acetate, 0.2g magnesium pidolate, and 9.6g maltodextrin that were diluted in 1.000mL water (measured osmotic concentration of 215mOsm L−1) and ESdext consisting of 5g sodium chloride, 1g potassium chloride, 1g calcium acetate, 0.2g magnesium pidolate, and 9.6g dextrose that were diluted in 1.000mL water (measured osmotic concentration of 243mOsm L−1). All solutions were administered at 15ml kg−1 h−1 for 4 hours. Both solutions increased the plasma volume in dehydrated dogs without causing adverse effects. However, ESmalt was more effective in promoting the increase in blood volume.(AU)

O presente estudo avaliou e comparou os efeitos de soluções eletrolíticas enterais hipotônicas, administradas por sonda nasoesofágica em fluxo contínuo em cães submetidos a restrição hídrica, sobre o hematócrito, proteínas totais séricas, osmolaridade sérica, volemia, glicose e lactato plasmáticos, hemogasometria, ânion gap e DIF. Foram utilizados seis cães adultos (quatro machos e duas fêmeas). Todos os animais foram submetidos aos dois tratamentos propostos, em um delineamento crossover 6×2. Os tratamentos foram os seguintes: SEmalt - 5g de cloreto de sódio, 1g de cloreto de potássio, 1g de acetato de cálcio, 0,2g de pidolato de magnésio e 9,6g de maltodextrina, diluídos em 1.000mL de água (osmolaridade mensurada: 215mOsm L -1 ); SEdext - 5g de cloreto de sódio, 1g de cloreto de potássio, 1g de acetato de cálcio, 0,2g de pidolato de magnésio e 9,6g de dextrose, diluídos em 1.000mL de água (osmolaridade mensurada: 243mOsm L -1 ). Todas as soluções foram administradas no volume de 15mL kg -1 hora -1 , durante quatro horas, em fluxo contínuo. Ambas as soluções aumentaram o volume plasmático em cães desidratados, sem gerar o aparecimento de efeitos adversos. Porém, a SEmalt foi mais eficaz em promover a expansão da volemia.

Hypotonic enteral electrolyte solutions administered by nasoesophageal tube in continuous flow in dogs dehydrated by water restriction: Part 1 / Soluções eletrolíticas enterais hipotônicas administradas por sonda nasoesofágica em fluxo contínuo em cães desidratados por restrição hídrica: Parte 1

The present study assessed and compared the effects of hypotonic enteral electrolyte solutions administered by nasoesophageal tube in continuous flow in dogs submitted to water restriction on packed cell volume; total serum protein and serum osmolarity concentrations; blood volume; plasma glucose and lactate levels; blood gas analysis, anion gap, and strong ion difference. Six adult dogs were used (four males and two females). All animals were submitted to both proposed treatments in a crossover design 6×2. The treatments were as follows: ESmalt consisting of 5g sodium chloride, 1g potassium chloride, 1g calcium acetate, 0.2g magnesium pidolate, and 9.6g maltodextrin that were diluted in 1.000mL water (measured osmotic concentration of 215mOsm L−1) and ESdext consisting of 5g sodium chloride, 1g potassium chloride, 1g calcium acetate, 0.2g magnesium pidolate, and 9.6g dextrose that were diluted in 1.000mL water (measured osmotic concentration of 243mOsm L−1). All solutions were administered at 15ml kg−1 h−1 for 4 hours. Both solutions increased the plasma volume in dehydrated dogs without causing adverse effects. However, ESmalt was more effective in promoting the increase in blood volume.(AU)

O presente estudo avaliou e comparou os efeitos de soluções eletrolíticas enterais hipotônicas, administradas por sonda nasoesofágica em fluxo contínuo em cães submetidos a restrição hídrica, sobre o hematócrito, proteínas totais séricas, osmolaridade sérica, volemia, glicose e lactato plasmáticos, hemogasometria, ânion gap e DIF. Foram utilizados seis cães adultos (quatro machos e duas fêmeas). Todos os animais foram submetidos aos dois tratamentos propostos, em um delineamento crossover 6×2. Os tratamentos foram os seguintes: SEmalt - 5g de cloreto de sódio, 1g de cloreto de potássio, 1g de acetato de cálcio, 0,2g de pidolato de magnésio e 9,6g de maltodextrina, diluídos em 1.000mL de água (osmolaridade mensurada: 215mOsm L -1 ); SEdext - 5g de cloreto de sódio, 1g de cloreto de potássio, 1g de acetato de cálcio, 0,2g de pidolato de magnésio e 9,6g de dextrose, diluídos em 1.000mL de água (osmolaridade mensurada: 243mOsm L -1 ). Todas as soluções foram administradas no volume de 15mL kg -1 hora -1 , durante quatro horas, em fluxo contínuo. Ambas as soluções aumentaram o volume plasmático em cães desidratados, sem gerar o aparecimento de efeitos adversos. Porém, a SEmalt foi mais eficaz em promover a expansão da volemia.

Evaluation of the use of tranexamic acid in total knee arthroplasty / Avaliação do uso do ácido tranexâmico em artroplastia total do joelho

ABSTRACT Objective: Evaluate the efficacy of tranexamic acid in reducing bleeding in patients undergoing total knee arthroplasty. Methods: 101 patients were randomized into two groups: the tranexamic acid group (n = 51) and the placebo group (n = 50). Patients were compared regarding the following parameters: reduction of hemoglobin, total estimated blood loss, drain output, and postoperative blood transfusion rate. Results: Comparing the groups, there were statistically significant differences (p < 0.05) in the following parameters: reduction of hemoglobin, decreased hematocrit, estimated blood loss, and drain output. All values were lower in the tranexamic acid group. Only placebo group patients required blood transfusion. Conclusion: The use of intravenous tranexamic acid is effective to reduce bleeding in patients undergoing total knee arthroplasty.

RESUMO Objetivo: Avaliar a eficácia do ácido tranexâmico na redução do sangramento em pacientes submetidos a artroplastia total de joelho. Métodos: Foram randomizados 101 pacientes em dois grupos: grupo ácido tranexâmico (n = 51) e grupo placebo (n = 50). Os pacientes foram comparados nos quesitos redução da hemoglobina, perda sanguínea total estimada, débito do dreno e taxa de hemotransfusão pós-operatória. Resultados: Na comparação entre os grupos, observou-se diferença estatística (p < 0,05) nos seguintes parâmetros: redução da hemoglobina, redução do hematócrito, perda sanguínea estimada e débito do dreno. Todos os valores foram menores no grupo do ácido tranexâmico. Somente pacientes do grupo placebo necessitaram de hemotransfusão. Conclusão: O uso de ácido tranexâmico intravenoso é eficaz para reduzir o sangramento dos pacientes submetidos a artroplastia total de joelho.

Evaluation of the use of tranexamic acid in total knee arthroplasty.

OBJECTIVE: Evaluate the efficacy of tranexamic acid in reducing bleeding in patients undergoing total knee arthroplasty. METHODS: 101 patients were randomized into two groups: the tranexamic acid group (n = 51) and the placebo group (n = 50). Patients were compared regarding the following parameters: reduction of hemoglobin, total estimated blood loss, drain output, and postoperative blood transfusion rate. RESULTS: Comparing the groups, there were statistically significant differences (p < 0.05) in the following parameters: reduction of hemoglobin, decreased hematocrit, estimated blood loss, and drain output. All values were lower in the tranexamic acid group. Only placebo group patients required blood transfusion. CONCLUSION: The use of intravenous tranexamic acid is effective to reduce bleeding in patients undergoing total knee arthroplasty.

OBJETIVO: Avaliar a eficácia do ácido tranexâmico na redução do sangramento em pacientes submetidos a artroplastia total de joelho. MÉTODOS: Foram randomizados 101 pacientes em dois grupos: grupo ácido tranexâmico (n = 51) e grupo placebo (n = 50). Os pacientes foram comparados nos quesitos redução da hemoglobina, perda sanguínea total estimada, débito do dreno e taxa de hemotransfusão pós-operatória. RESULTADOS: Na comparação entre os grupos, observou-se diferença estatística (p < 0,05) nos seguintes parâmetros: redução da hemoglobina, redução do hematócrito, perda sanguínea estimada e débito do dreno. Todos os valores foram menores no grupo do ácido tranexâmico. Somente pacientes do grupo placebo necessitaram de hemotransfusão. CONCLUSÃO: O uso de ácido tranexâmico intravenoso é eficaz para reduzir o sangramento dos pacientes submetidos a artroplastia total de joelho.

Evaluation of end-tidal carbon dioxide gradient as a predictor of volume responsiveness in spontaneously breathing healthy adults.

BACKGROUND: Methods to guide fluid therapy in spontaneously breathing patients are scarce. No studies have reported the accuracy of end-tidal CO2 (ET-CO2) to predict volume responsiveness in these patients. We sought to evaluate the ET-CO2 gradient (ΔET-CO2) after a passive leg rise (PLR) maneuver to predict volume responsiveness in spontaneously breathing healthy adults. METHODS: We conducted a prospective study in healthy adult human volunteers. A PLR maneuver was performed and cardiac output (CO) was measured by transthoracic echocardiography. ET-CO2 was measured with non-invasive capnographs. Volume responsiveness was defined as an increase in cardiac output (CO) > 12% at 90 s after PLR. RESULTS: Of the 50 volunteers, 32% were classified as volume responders. In this group, the left ventricle outflow tract velocity time integral (VTILVOT) increased from 17.9 ± 3.0 to 20.4 ± 3.4 (p = 0.0004), CO increased from 4.4 ± 1.5 to 5.5 ± 1.6 (p = 0.0), and ET-CO2 rose from 32 ± 4.84 to 33 ± 5.07 (p = 0.135). Within the entire population, PLR-induced percentage ∆CO was not correlated with percentage ∆ET-CO2 (R2 = 0.13; p = 0.36). The area under the receiver operating curve for the ability of ET-CO2 to discriminate responders from non-responders was of 0.67 ± 0.09 (95% CI 0.498-0.853). A ΔET-CO2 ≥ 2 mmHg had a sensitivity of 50%, specificity of 97.06%, positive likelihood ratio of 17.00, negative likelihood ratio of 0.51, positive predictive value of 88.9%, and negative predictive value of 80.5% for the prediction of fluid responsiveness. CONCLUSIONS: ΔET-CO2 after a PLR has limited utility to discriminate responders from non-responders among healthy spontaneously breathing adults.

Hemodinámica funcional: ¿Qué significa "ser respondedor"? / Functional hemodynamics: "Be responsive, what does this mean"?

The conventional analysis and approach to the physiology of the fluid responsiveness has traditionally been focused mainly on the physiology of heart-lung interactions, and on reviews of the technical, methodological, and epidemiological aspects of the dynamic parameters, which are translated into simple algorithms to assess fluid responsiveness and to guide fluid therapy.However, fundamental features of the dynamics of the peripheral circulation, heart-vasculature interaction, and blood volume distribution, are overlooked and sometimes not accounted for, motivating misconceptions about the cardiovascular system's response to fluid administration and fluid management, such as equating fluid loading with cardiac preload, a predictable interpretation whenever Starling's ventricular function curve is analyzed in isolation. This paper reexamines fluid responsiveness' rationale offering a broadened perspective on the circulatory phenomena involved in the physiological interaction between BV, cardiac preload and output, and stroke volume variation. Finally, implications relevant in physiological and clinical terms are discussed.

El análisis convencional y abordaje actual de la fisiología de la "respuesta a fluidos" (RF) ha estado focalizada principalmente sobre la fisiología de la interacción cardiopulmonar, y sobre aspectos técnicos, metodológicos y, epidemiológicos de los parámetros dinámicos, los cuales son traducidos en algoritmos simplificados para evaluar la RF y guiar la fluidoterapia. Sin embargo, aspectos fundamentales de la dinámica de la circulación periférica, el acoplamiento entre el corazón y la vasculatura, y la distribución del volumen sanguíneo son frecuentemente omitidos, motivando mal interpretaciones sobre la respuesta del sistema cardiovascular a la administración de fluidos, tal como equiparar la carga de fluidos con la precarga ventricular, una consecuencia predecible al interpretar la curva de función ventricular (Starling) de forma aislada. Así, esta revisión reexamina la rationale de la RF, ofreciendo una perspectiva ampliada sobre aquellos fenómenos circulatorios implicados en la interacción entre el volumen sanguíneo, la precarga ventricular, el gasto cardíaco y la variación del volumen sistólico. Finalmente, se analizarán las implicancias prácticas y conceptuales.

Delayed Cord Clamping in Newborns Born at Term at Risk for Resuscitation: A Feasibility Randomized Clinical Trial.

Infants may benefit if resuscitation could be provided with an intact umbilical cord. Infants identified at risk for resuscitation were randomized to 1- or 5-minute cord clamping. The 5-minute group had greater cerebral oxygenation and blood pressure. Studies are needed to determine whether this translates into improved outcomes. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02827409.