Ultrassonografia da veia cava inferior na avaliação do volume intravascular e fluido-responsividade em pacientes críticos: uma revisão sistemática / Inferior vena cava ultrasound for assessing volume status and fluid responsiveness in critically ill patients: a systematic review

Fundamento: A avaliação do volume intravascular e da fluido-responsividade é uma condição desafiadora no manejo de pacientes críticos. Os métodos diagnósticos precisam garantir segurança, reprodutibilidade e praticidade no monitoramento hemodinâmico. Objetivo: Descrever a aplicabilidade dos índices ultrassonográficos da veia cava inferior na avaliação do volume intravascular e na predição da fluido-responsividade em pacientes críticos. Método: Trata-se de revisão sistemática realizada por meio das bases de dados PubMed®, Lilacs e SciELO nos 5 anos anteriores. Os descritores utilizados foram "inferior vena cava", "ultrasonography", "fluid-responsiveness" e "volume status". Resultados: Foram selecionados 13 artigos compatíveis com os objetivos deste estudo. O índice de colapsibilidade da veia cava inferior variou de 25% a 50% como ponto de corte para definição de hipovolemia. Além disso, apresentou aplicabilidade na predição da fluido-responsividade em pacientes sob respiração espontânea, com pontos de corte variando de 25% a 57%. Em cenários de ventilação mecânica, o índice de distensibilidade da veia cava inferior mostrou-se mais eficaz, quando comparado às demais medidas, para predição de fluido-responsividade, mas foi encontrada variação de 10,2% a 20,5%. O índice diâmetro da veia cava inferior/diâmetro da artéria aorta foi especialmente útil na população pediátrica para definição do volume intravascular, mas em adultos existiram muitas divergências quanto à sua aplicabilidade. Conclusão: A avaliação do volume intravascular e da fluido-responsividade por meio dos índices ultrassonográficos da veia cava inferior apresenta aplicabilidade e segurança no diagnóstico e no monitoramento da instabilidade hemodinâmica. Entretanto, são necessários estudos de padronização de valores em razão das divergências quanto aos pontos de corte utilizados em cada índice.(AU)

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.

What Factors can Influence Massive Blood Loss in the Surgical Treatment of Neuromuscular Scoliosis? / Quais fatores podem influenciar perdas sanguíneas extensas no tratamento cirúrgico da escoliose neuromuscular?

Abstract Objective The aim of the present study is to identify the incidence, predisposing factors and prognostic impact of blood loss in patients with neuromuscular scoliosis submitted to corrective surgery. Methods Retrospective cohort study, including pediatric patients diagnosed with neuromuscular scoliosis undergoing instrumentation and posterior vertebral fusion in a university hospital. Patient characteristics were collected from the hospital information system. Results A total of 39 patients were included in the study. The intraoperative blood losses were 962 ml, representing a loss of 35.63% of the blood volume. In 20 cases, there was a massive blood loss (> 30%) and only 7 patients did not need a transfusion. The group of patients with massive blood loss had a slightly higher age (13.75 versus 13.53 years old), a lower body mass index (BMI) percentile (25 versus 50), and for each decrease of 0.38 in the BMI, intraoperative blood losses increased 1% (p < 0.05). The value of preoperative albumin had influence on the percentage of blood loss, and for each decrease of 0.4 of albumin, blood loss increased 1% (p < 0.05). Conclusions The factors that most contributed to the differences in blood loss were age, BMI, and preoperative albumin value. There was no significant association between Cobb angle, number of fusion levels and duration of surgery. We can conclude that these patients would benefit from preoperative nutritional control.

Resumo Objetivo O objetivo do presente estudo é identificar a incidência, os fatores predisponentes e o impacto prognóstico da perda de sangue em pacientes com escoliose neuromuscular submetidos a cirurgia corretiva. Métodos Estudo de coorte retrospectiva, incluindo pacientes pediátricos com diagnóstico de escoliose neuromuscular submetidos a instrumentação e fusão vertebral posterior em um hospital universitário. As características dos pacientes foram coletadas no sistema de informações do hospital. Resultados Um total de 39 pacientes foram incluídos no estudo. As perdas sanguíneas intraoperatórias foram de 962 mL, representando uma perda de 35,63% do volume sanguíneo; a perda de sangue foi extensa em 20 casos (> 30%) e apenas 7 pacientes não necessitaram de transfusão. O grupo de pacientes com perda maciça de sangue apresentou idade um pouco maior (13,75 versus 13,53 anos) e menor percentil do índice de massa corporal (IMC) (25 versus 50); para cada diminuição de 0,38 no IMC, as perdas sanguíneas intraoperatórias aumentaram 1% (p < 0,05). A concentração pré-operatória de albumina influenciou o percentual de perda de sangue e, para cada diminuição de 0,4 de albumina, a perda de sangue aumentou 1% (p < 0,05). Conclusões Os fatores que mais contribuíram para as diferenças na perda sanguínea foram idade, IMC e concentração pré-operatória de albumina. Não houve associação significativa entre ângulo de Cobb, número de níveis de fusão e duração da cirurgia. Podemos concluir que esses pacientes se beneficiariam do controle nutricional pré-operatório.

Impacto del volumen de sangre extraído por flebotomía sobre el requerimiento transfusional en prematuros menores de 1500 g. Estudio cuasiexperimental / Impact of the volume of blood collected by phlebotomy on transfusion requirements in preterm infants with birth weight of less than 1500 g. A quasi-experimental study

Introducción. La anemia es una complicación para los recién nacidos de muy bajo peso al nacer, y los exámenes de laboratorio son un factor de riesgo preponderante. Más del 50 % recibe, al menos, una transfusión de glóbulos rojos. Estas se han asociado a mayor riesgo de infecciones, hemorragia intracraneal, enterocolitis necrotizante y displasia broncopulmonar. En 2012, se implementó, en el Hospital Italiano de Buenos Aires, una estrategia de menor volumen de extracción de sangre por flebotomía. El objetivo del presente estudio fue evaluar su asociación con el número detransfusiones.Métodos. Estudio cuasiexperimental del tipo antes/después. Se comparó el número de transfusiones entre dos grupos de prematuros de muy bajo peso con diferente volumen de extracción. Se evaluó la correlación entre el volumen extraído y el número de transfusiones estimando el coeficiente de Spearman. Para ajustar por confundidores, se realizó un modelo de regresión logística.Resultados. Se incluyeron en el estudio 178 pacientes con edad gestacional media de 29,4 semanas (desvío estándar: 2,7) y peso al nacer de 1145 gramos (875-1345). El perfil de la serie roja inicial fue similar entre ambos grupos. El número de transfusiones (p = 0,017) y el volumen transfundido (p = 0,048) disminuyeron significativamente. El coeficiente de correlación resultó de 0,83. En el análisis multivariado, volumen de extracción y peso al nacer se asociaron a un requerimiento mayor de 3 transfusiones.Conclusión. Un menor volumen de extracción de sangre en prematuros de muy bajo peso está asociado de manera independiente a menor requerimiento transfusional.

Introduction. Anemia is a complication in very low birth weight (VLBW) infants, and lab tests are a predominant risk factor. At least one red blood cell transfusion is given in more than 50 % of cases. Transfusions are associated with a higher risk for infections, intracranial hemorrhage, necrotizing enterocolitis, and bronchopulmonary dysplasia. In 2012, Hospital Italiano de Buenos Aires implemented a strategy to collect a lower blood volume by phlebotomy. The objective of this study was to assess its association with the number of transfusions.Methods. Before-and-after, quasi-experimental study. The number of transfusions was compared between two groups of VLBW preterm infants with different blood collection volumes. The correlation between the collection volume and the number of transfusions was assessed estimating Spearman's coefficient. A logistic regression model was used to adjust for confounders.Results. The study included 178 patients with a mean gestational age of 29.4 weeks (standard deviation: 2.7) and a birth weight of 1145 g (875-1345). The baseline red series profile was similar between both groups. The number of transfusions (p = 0.017) and the transfusion volume (p = 0.048) decreased significantly. The correlation coefficient was 0.83. In the multivariate analysis, collection volume and birth weight were associated with a requirement of more than three transfusions.Conclusion. A lower blood collection volume in VLBW preterm infants is independently associated with fewer transfusion requirements.

A Light Adaptive Heart Rate Detection Method Based on Webcam / 中国医疗器械杂志

In order to extract the pulse wave signal of blood volume effectively in the case of uneven light, a light-adaptive heart rate detection method based on webcam was proposed. In this method, adaptive gamma transform is applied to face image sequence to eliminate the influence of illumination. The pulse wave source signal was extracted from the forehead area and the blood volume pulse wave was obtained by wavelet filtering. The heart rate is estimated by Fourier transform analysis. The Bland-Altman analysis indicates that the method used in this paper is in good agreement with the measurement results of the electronic sphygmomanometer, and the adaptive gamma transformation used in this paper eliminates the influence of light interference, and the measurement error of heart rate is significantly reduced, which is completely able to meet the requirements of daily heart rate monitoring.

Conservation of both hematocrit and liver regeneration in hepatectomies: a vascular occlusion approach in rats / Hepatectomia hemoconservadora no rato: preservação do hematócrito e da regeneração hepática

ABSTRACT Background: Hepatectomies promote considerable amount of blood loss and the need to administrate blood products, which are directly linked to higher morbimortality rates. The blood-conserving hepatectomy (BCH) is a modification of the selective vascular occlusion technique. It could be a surgical maneuver in order to avoid or to reduce the blood products utilization in the perioperative period. Aim: To evaluate in rats the BCH effects on the hematocrit (HT) variation, hemoglobin serum concentration (HB), and on liver regeneration. Methods: Twelve Wistar rats were divided into two groups: control (n=6) and intervention (n=6). The ones in the control group had their livers partially removed according to the Higgins and Anderson technique, while the rats in the treatment group were submitted to BCH technique. HT and HB levels were measured at day D0, D1 and D7. The rate between the liver and rat weights was calculated in D0 and D7. Liver regeneration was quantitatively and qualitatively evaluated. Results: The HT and HB levels were lower in the control group as of D1 onwards, reaching an 18% gap at D7 (p=0.01 and p=0.008, respectively); BCH resulted in the preservation of HT and HB levels to the intervention group rats. BCH did not alter liver regeneration in rats. Conclusion: The BCH led to beneficial effects over the postoperative HT and serum HB levels with no setbacks to liver regeneration. These data are the necessary proof of evidence for translational research into the surgical practice.

RESUMO Racional: As hepatectomias compreendem considerável perda sanguínea e utilização de hemoderivados, o que diretamente estão relacionados com maior morbimortalidade. A hepatectomia hemoconservadora (HH) é modificação da técnica de oclusão vascular seletiva em hepatectomia. Ela pode ser alternativa cirúrgica para evitar ou diminuir o uso de hemoderivados no perioperatório. Objetivo: Avaliar os efeitos da HH sobre o volume globular (VG), concentração de hemoglobina (HB) e sobre a regeneração hepática em ratos. Métodos: Dois grupos de ratos Wistar foram constituídos: controle (n=6) e intervenção (n=6). Os do grupo controle foram submetidos à hepatectomia parcial de Higgins e Anderson e os do grupo Intervenção à HH. VG e HB foram medidos nos dias D0, D1 e D7. A relação peso do fígado/peso do rato foi calculada em D0 e D7. A regeneração hepática foi analisada qualitativamente e quantitativamente. Resultados: Houve diminuição dos níveis de VG e HB nos ratos do grupo controle a partir de D1, atingindo decréscimo de 18% em D7 (p=0,01 e p=0,008 respectivamente); a HH permitiu a manutenção dos níveis de VG e HB nos ratos do grupo intervenção. A HH não alterou a regeneração hepática. Conclusão: HH resultou em níveis maiores de VG e HB pós-operatórios sem alterar a regeneração hepática. Pode-se considerar estes dados como a prova necessária para a translação à pesquisa clinicocirúrgica.

Utilidad del protocolo focused assessment with transthoracic echocardiography (FATE) en la evaluación del paciente con shock / The usefulness of the (FATE) protocol focused assessment with transthoracic echocardiography in patients with shock

Determinar la utilidad del protocolo FATE (Focused Assessment with Transthoracic Echocardiography) en la evaluación de los pacientes en shock. ingresados al Servicio de Cuidados Intermedios del Hospital Central Universitario Dr. "Antonio María Pineda", Barquisimeto, Venezuela en el período agosto-octubre 2019, Métodos: se realizó un estudio descriptivo transversal, de 30 pacientes, con promedio de edad de 56,86 ± 15,85 años, Resultados: predominó el grupo de 71-80 años (23,33%), de sexo masculino (63,33%). Según la clasificación del shock por Weil y Shubin el 50% presentó shock distributivo (todos por sepsis), 20% cardiogénico, 16,67% hipovolémico y obstructivo. 13,33% Los principales hallazgos ecocardiográficos fueron presencia de derrame pleural bilateral (33,33%), derrame pleural unilateral (30%) y derrame pericárdico (23,33%). Además, 26,67% presentaron espesor miocárdico patológico, 33,33% dimensiones de VD-VI aumentadas, 46,67% función sistólica ventricular alterada; sumado al hecho que 70% de la contractibilidad y 60% de la visualización pulmonar eran patológicas. El valor cualitativo del protocolo FATE resultó en: 43,33% soportaba la información disponible, 26,67% añadió información decisiva a la terapéutica, 23,33% agregó nueva información y 6,67% información fue pobre por mala ventana. La mortalidad a los 7 días fue de 43,33%, siendo más frecuente en pacientes con shock distributivo (61,54%), seguido de cardiogénico (23,08%) y obstructivo (15,38%), no hubo defunciones por shock hipovolémico. Los valores cualitativos del protocolo FATE en pacientes fallecidos; por shock distributivo 37,5%, soportó la información disponible y agregó nueva información, respectivamente. En cambio en 100% de los fallecidos por shock cardiogénico y obstructivo, el protocolo FATE añadió información decisiva a la terapéutica. Los resultados demuestran la importancia del Protocolo FATE en el manejo de pacientes con shock(AU)

To determine the usefulness of the FATE protocol (Focused Assessment with Transthoracic Echocardiography) in the evaluation of patients in shock admitted to the Intermediate Care Unit of the "University Hospital Antonio Maria Pineda" in Barquisimeto, Venezuela, during the period August-October 2019, Methods: A descriptive cross-sectional study was done, selecting 30 patients, with an average age of 56.86 ± 15.85 years; the most affected group was 71-80 years old (23.33%), with a predominance of the male sex (63.33%) Results: According to the classification of shock by Weil and Shubin, 50% were found to have distributive shock (all due to sepsis), 20% cardiogenic, 16.67% hypovolemic and obstructive 13.33%. The main echocardiographic findings were the presence of bilateral pleural effusion (33.33%), unilateral pleural effusion (30%) and pericardial effusion (23.33%). In addition, 26.67% presented pathological myocardial thickness, 33.33% increased RV-LV dimensions, 46.67% impaired ventricular systolic function; also, 70% of contractibility and 60% of pulmonary visualization were pathological. The qualitative value of the FATE protocol resulted in: 43.33% supported the available information, 26.67% added decisive information to the therapy, 23.33% added new information and 6.67% information was poor due to a bad US window. (Mortality at 7 days was 43.33%, being more frequent in patients with distributive shock (61.54%), followed by cardiogenic (23.08%) and obstructive (15.38%); there were no deaths due to hypovolemic shock. The qualitative values of the FATE protocol in patients with distributive shock who died, was that 37.5% In contrast, in 100% of those who died by cardiogenic and obstructive shock, the FATE protocol added decisive information to the therapy. Conclusion:The results demonstrate the importance of the FATE Protocol in the management of patients with shock(AU)

Effect of the lateral tilt position on femoral vein cross-sectional area in anesthetized adults

BACKGROUND: A lateral tilt position can affect the size of the femoral vein (FV) due to increased venous blood volume in the dependent side of the body. METHODS: Forty-two patients, aged 20–60 years, were enrolled in this study. The crosssectional area (CSA), anteroposterior, and transverse diameters of the FV were measured 1 cm below the left inguinal line using ultrasound. The value of each parameter was recorded in the following four positions: (1) supine, (2) supine + 10° left-lateral tilt (LLT), (3) 10° reverse Trendelenburg (RT), and (4) RT + LLT. RESULTS: CSAs of the left FV in the supine, supine + LLT, RT, RT + LLT positions were 0.93 ± 0.22, 1.11 ± 0.29, 1.17 ± 0.29, and 1.31 ± 0.32 cm2, respectively. Compared to the supine position, there was a significant increase in CSA and anteroposterior diameter according to the three changed positions. The transverse diameter of the left FV was significantly increased in supine + LLT, RT, RT + LLT positions compared to that in the supine position (P = 0.010, P = 0.043, P = 0.001, respectively). There was no significant difference in the transverse diameter of the left FV between the supine + LLT and RT positions (P = 1.000). CONCLUSIONS: Adding LLT to the supine and RT positions increased the CSA of the unilateral FV significantly.

Myocardial Blood Flow Quantified by Low-Dose Dynamic CT Myocardial Perfusion Imaging Is Associated with Peak Troponin Level and Impaired Left Ventricle Function in Patients with ST-Elevated Myocardial Infarction

OBJECTIVE: To investigate the association of myocardial blood flow (MBF) quantified by dynamic computed tomography (CT) myocardial perfusion imaging (MPI) with troponin level and left ventricle (LV) function in patients with ST-segment elevated myocardial infarction (STEMI). MATERIALS AND METHODS: Thirty-five STEMI patients who successfully had undergone reperfusion treatment within 1 week of their infarction were consecutively enrolled. All patients were referred for dynamic CT-MPI. Serial high-sensitivity troponin T (hs-TnT) levels and left ventricular ejection fraction (LVEF) measured by echocardiography were recorded. Twenty-six patients with 427 segments were included for analysis. Various quantitative parameters derived from dynamic CT-MPI were analyzed to determine if there was a correlation between hs-TnT levels and LVEF on admission and again at the 6-month mark. RESULTS: The mean radiation dose for dynamic CT-MPI was 3.2 ± 1.1 mSv. Infarcted territories had significantly lower MBF (30.5 ± 7.4 mL/min/100 mL versus 73.4 ± 8.1 mL/min/100 mL, p < 0.001) and myocardial blood volume (MBV) (2.8 ± 0.9 mL/100 mL versus 4.2 ± 1.1 mL/100 mL, p = 0.044) compared with those of reference territories. MBF showed the best correlation with the level of peak hs-TnT (r = −0.682, p < 0.001), and MBV showed a moderate correlation with the level of peak hs-TnT (r = −0.437, p = 0.026); however, the other parameters did not show any significant correlation with hs-TnT levels. As for the association with LV function, only MBF was significantly correlated with LVEF at the time of admission (r = 0.469, p = 0.016) and at 6 months (r = 0.585, p = 0.001). CONCLUSION: MBF quantified by dynamic CT-MPI is significantly inversely correlated with the level of peak hs-TnT. In addition, patients with lower MBF tended to have impaired LV function at the time of their admission and at 6 months.

Dynamic Contrast-Enhanced Ultrasound of Gastric Cancer: Correlation with Perfusion CT and Histopathology

OBJECTIVE: To assess the relationship between contrast-enhanced ultrasound (CEUS) parameters and perfusion CT (PCT) parameters of gastric cancers and their correlation with histologic features. MATERIALS AND METHODS: This prospective study was approved by our Institutional Review Board. We included 43 patients with pathologically-proven gastric cancers undergoing CEUS using SonoVue® (Bracco) and PCT on the same day. Correlation between the CEUS parameters (peak intensity [PI], area under the curve [AUC], rise time [RT] from 10% to 90% of PI, time to peak [TTPUS], and mean transit time [MTTUS]) and PCT parameters (blood flow, blood volume, TTPCT, MTTCT, and permeability surface product) of gastric cancers were analyzed using Spearman's rank correlation test. In cases of surgical resection, the CEUS and PCT parameters were compared according to histologic features using Mann-Whitney test. RESULTS: CEUS studies were of diagnostic quality in 88.4% (38/43) of patients. Among the CEUS parameters of gastric cancers, RT and TTPUS showed significant positive correlations with TTPCT (rho = 0.327 and 0.374, p = 0.045 and 0.021, respectively); PI and AUC were significantly higher in well-differentiated or moderately-differentiated tumors (n = 4) than poorly-differentiated tumors (n = 18) (p = 0.026 and 0.033, respectively), whereas MTTCT showed significant differences according to histologic types (poorly cohesive carcinoma [PCC] vs. non-PCC), T-staging (≤ T2 vs. ≥ T3), N-staging (N0 vs. N-positive), and epidermal growth factor receptor expression (≤ faint vs. ≥ moderate staining) (p values < 0.05). CONCLUSION: In patients with gastric cancers, CEUS is technically feasible for the quantification of tumor perfusion and may provide correlative and complementary information to that of PCT, which may allow prediction of histologic features.

Prevalence of Decreased Myocardial Blood Flow in Symptomatic Patients with Patent Coronary Stents: Insights from Low-Dose Dynamic CT Myocardial Perfusion Imaging

OBJECTIVE: To study the prevalence and clinical characteristics of decreased myocardial blood flow (MBF) quantified by dynamic computed tomography (CT) myocardial perfusion imaging (MPI) in symptomatic patients without in-stent restenosis. MATERIALS AND METHODS: Thirty-seven (mean age, 71.3 ± 10 years; age range, 48–88 years; 31 males, 6 females) consecutive symptomatic patients with patent coronary stents and without obstructive de novo lesions were prospectively enrolled to undergo dynamic CT-MPI using a third-generation dual-source CT scanner. The shuttle-mode acquisition technique was used to image the complete left ventricle. A bolus of contrast media (50 mL; iopromide, 370 mg iodine/mL) was injected into the antecubital vein at a rate of 6 mL/s, followed by a 40-mL saline flush. The mean MBF value and other quantitative parameters were measured for each segment of both stented-vessel territories and reference territories. The MBFratio was defined as the ratio of the mean MBF value of the whole stent-vessel territory to that of the whole reference territory. An MBFratio of 0.85 was used as the cut-off value to distinguish hypoperfused from non-hypoperfused segments. RESULTS: A total of 629 segments of 37 patients were ultimately included for analysis. The mean effective dose of dynamic CT-MPI was 3.1 ± 1.2 mSv (range, 1.7–6.3 mSv). The mean MBF of stent-vessel territories was decreased in 19 lesions and 81 segments. Compared to stent-vessel territories without hypoperfusion, the mean MBF and myocardial blood volume were markedly lower in hypoperfused stent-vessel territories (77.5 ± 16.6 mL/100 mL/min vs. 140.4 ± 24.1 mL/100 mL/min [p < 0.001] and 6.4 ± 3.7 mL/100 mL vs. 11.5 ± 4 mL/100 mL [p < 0.001, respectively]). Myocardial hypoperfusion in stent-vessel territories was present in 48.6% (18/37) of patients. None of clinical parameters differed statistically significantly between hypoperfusion and non-hypoperfusion subgroups. CONCLUSION: Decreased MBF is commonly present in patients who are symptomatic after percutaneous coronary intervention, despite patent stents and can be detected by dynamic CT-MPI using a low radiation dose.

Accuracy of BacT/Alert Virtuo for Measuring Blood Volume for Blood Culture

No abstract available.

Normal Reference Plots for the Bioelectrical Impedance Vector in Healthy Korean Adults

BACKGROUND: Accurate volume measurement is important in the management of patients with congestive heart failure or renal insufficiency. A bioimpedance analyser can estimate total body water in litres and has been widely used in clinical practice due to its non-invasiveness and ease of results interpretation. To change impedance data to volumetric data, bioimpedance analysers use equations derived from data from healthy subjects, which may not apply to patients with other conditions. Bioelectrical impedance vector analysis (BIVA) was developed to overcome the dependence on those equations by constructing vector plots using raw impedance data. BIVA requires normal reference plots for the proper interpretation of individual vectors. The aim of this study was to construct normal reference vector plots of bioelectrical impedance for Koreans. METHODS: Bioelectrical impedance measurements were collected from apparently healthy subjects screened according to a comprehensive physical examination and medical history performed by trained physicians. Reference vector contours were plotted on the RXc graph using the probability density function of the bivariate normal distribution. We further compared them with those of other ethnic groups. RESULTS: A total of 242 healthy subjects aged 22 to 83 were recruited (137 men and 105 women) between December 2015 and November 2016. The centers of the tolerance ellipses were 306.3 Ω/m and 34.9 Ω/m for men and 425.6 Ω/m and 39.7 Ω/m for women. The ellipses were wider for women than for men. The confidence ellipses for Koreans were located between those for Americans and Spaniards without overlap for both genders. CONCLUSION: This study presented gender-specific normal reference BIVA plots and corresponding tolerance and confidence ellipses on the RXc graph, which is important for the interpretation of BIA-reported volume status in patients with congestive heart failure or renal insufficiency. There were noticeable differences in reference ellipses with regard to gender and ethnic groups.

Increased white matter diffusivity associated with phantom limb pain

BACKGROUND: We utilized diffusion tensor imaging (DTI) to evaluate the cerebral white matter changes that are associated with phantom limb pain in patients with unilateral arm amputation. It was anticipated that this would complement previous research in which we had shown that changes in cerebral blood volume were associated with the cerebral pain network. METHODS: Ten patients with phantom limb pain due to unilateral arm amputation and sixteen healthy age-matched controls were enrolled. The intensity of phantom limb pain was measured by the visual analogue scale (VAS) and depressive mood was assessed by the Hamilton depression rating scale. Diffusion tensor-derived parameters, including fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD), were computed from the DTI. RESULTS: Compared with controls, the cases had alterations in the cerebral white matter as a consequence of phantom limb pain, manifesting a higher AD of white matter in both hemispheres symmetrically after adjusting for individual depressive moods. In addition, there were associations between the RD of white matter and VAS scores primarily in the hemispheres related to the missing hand and in the corpus callosum. CONCLUSIONS: The phantom limb pain after unilateral arm amputation induced plasticity in the white matter. We conclude that loss of white matter integrity, particularly in the hemisphere connected with the missing hand, is significantly correlated with phantom limb pain.

Investigation of the effects of temporomandibular joint arthrocentesis on blood volume of the retinal structures

OBJECTIVE: Arthrocentesis is a minimally invasive surgical procedure that is used to alleviate the symptoms of temporomandibular joint (TMJ) disorders. The aim of this study was to investigate the effect of arthrocentesis on the blood supply to the retinal structures. MATERIALS AND METHODS: Arthrocentesis was performed on 20 patients with TMJ disorders, and choroidal thickness (CT) in patients was measured to evaluate retinal blood circulation. The blood volume of the retinal structures was evaluated ipsilaterally before and after arthrocentesis, and these measurements were then compared with measurements obtained from the contralateral side. RESULTS: Before arthrocentesis, there were no differences in retinal blood volumes between the ipsilateral and contralateral sides (P = 0.96). When ipsilateral CT measurements taken before and after arthrocentesis were compared, retinal blood supply was found to have significantly decreased after arthrocentesis (P = 0.04). When contralateral CT measurements taken before and after arthrocentesis were compared, retinal blood supply was also found to have decreased after arthrocentesis, but not significantly (P = 0.19). CONCLUSION: The solution of local anesthesia with epinephrine applied before the arthrocentesis procedure was found to reduce the blood volume of the retinal structures. To the best of our knowledge, this is the first study that has investigated the blood volume of the retinal structures following arthrocentesis.

Assessment of the prescription of red blood cell concentrates in the pediatric age group / Avaliação da prescrição de concentrados de hemácias na faixa etária pediátrica

Summary Objective: To verify the adequacy of red blood cell (RBC) prescription to pediatric patients in different sectors of a pediatric hospital. Method: A retrospective study was conducted including 837/990 RBC transfusion requisition forms for children and adolescents (0 to 13 years old) filed in between January 2007 and April 2015 by the pediatricians of the emergency room (ER), infirmary ward and intensive care unit (pICU). Transfusion requisition forms belonging to patients with chronic anemia or acute hemorrhage, as well as incompletes requisition forms, were excluded. Results: Trigger, prescribed volume and subtype of RBC concentrates were adequate in 532 (65.3%), 460 (58.8%) and 805 (96.2%) of the transfusions, respectively. When the clinical picture was considered, prescription adequacy was higher compared to the use of the hemoglobin level alone (70.9% vs. 41%). The pICU had the highest correct trigger percentage (343 [71.6%]; p<0.001) while the ER showed more often adequate prescribed volumes (119 [66.1%]; p=0.020). The most common inadequacy regarding volume was that of prescriptions above the recommendation > 15 mL/kg found in 309 cases (36.9%). Thirty-two (32) RBC subtypes were requested and none were consistent with current recommendations. Conclusion: The results obtained in our study showed that RBC transfusion occurred more appropriately when the clinical picture was taken into account at request. There was a tendency to prescribe higher volumes and RBC subtypes without the justification of current protocols. Hemotherapic teachings at undergraduate level and medical residency must be improved.

Resumo Objetivo: Verificar a adequação na prescrição de concentrado de hemácias (CH) por pediatras em diferentes setores de um hospital pediátrico. Método: Realizou-se estudo retrospectivo onde avaliamos 837/990 fichas de requisição de CH para crianças e adolescentes (0 a 13 anos), preenchidas entre janeiro de 2007 e abril de 2015 pelos médicos pediatras do pronto-socorro (PS), da enfermaria e da unidade de terapia intensiva (UTI). Excluíram-se as transfusões realizadas em portadores de anemia crônica, crianças com hemorragia aguda e requisições incompletas. Resultados: Gatilho, volume prescrito e subtipo de concentrado de hemácias foram adequados em 532 (65,3%), 460 (58,8%) e 805 (96,2%) das transfusões, respectivamente. Quando foi considerado o quadro clínico, a adequação foi maior em comparação à prescrição pelo valor isolado da hemoglobina (70,9% vs. 41%). A UTI teve o maior percentual de acerto no gatilho (343 [71,6%]; p<0,001) e o PS, no volume prescrito (119 [66,1%]; p=0,020). A inadequação mais comum, em relação ao volume, foi a prescrição acima da recomendação (> 15 mL/kg, 309 [36,9%]). Foram solicitados 32 subtipos de CH e nenhum estava de acordo com as indicações atuais. Conclusão: Os resultados obtidos mostram que a transfusão de CH aconteceu de forma mais adequada quando a situação clínica era levada em conta na solicitação. Houve uma tendência à prescrição de volumes elevados e de subtipos de hemácias não justificados segundo os protocolos atuais. É necessário melhorar o ensino de hemoterapia na graduação e residência médica.

Cerebral Blood Volume Magnetic Resonance Imaging

Cerebral blood volume (CBV) is a hemodynamic correlate of oxygen metabolism and changes due to neuronal activity. CBV alteration may precede other hemodynamic correlates and provide an early indication of hemodynamic impairment. CBV can be easily quantified using magnetic resonance imaging (MRI); moreover, CBV MRI has a strong point of high resolution compared to other neuroimaging modalities. The early and accurate assessments of cerebral metabolism and the brain map with the high resolution of CBV MRI enable advanced neurorehabilitation examinations in a neuroimaging study.

Hemodynamic analysis of radiation-induced damage in common carotid arteries by using color Doppler ultrasonography

PURPOSE: The aim of this study was to assess vascular changes and blood flow abnormalities in the common carotid arteries of patients with head and neck cancers after external radiotherapy, using color Doppler ultrasonography. METHODS: We studied 24 patients treated with external radiotherapy for various head and neck cancers. In order to study the acute effects of irradiation on common carotid blood flow and arterial diameter changes, color Doppler ultrasonography parameters such as peak systolic velocity, end diastolic velocity, mean velocity, systolic-to-diastolic velocity (S/D) ratio, pulsatility index (PI), resistive index (RI), and instantaneous diameter changes were evaluated before and after external radiotherapy. Additionally, the blood volume flow (VF) values in the peak systolic and end diastolic phases, as well as mean velocity, were evaluated throughout three cardiac cycles using B-mode ultrasonic image processing. RESULTS: The findings showed significant changes in the S/D ratio, PI, and RI of the common carotid arteries before and after external radiotherapy (P < 0.05). Moreover, a significant decrease in artery diameter and blood VF was observed after radiotherapy relative to the pretreatment values. A significant correlation was found between the blood VF values estimated using ultrasonic measurements and mathematical methods throughout three cardiac cycles. CONCLUSION: The hemodynamic parameters of the common carotid arteries changed during radiotherapy. These arterial changes may lead to late adverse effects of radiotherapy, such as ischemic strokes and ischemic attacks.