Association Between Optic Nerve Head Blood Flow Measured Using Laser Speckle Flowgraphy and Radial Arterial Pressure During Aortic Arch Surgery.

OBJECTIVE: This study was designed to investigate the association between ocular blood flow measured using laser speckle flowgraphy (LSFG) and radial arterial pressure during aortic arch surgery. DESIGN: A prospective study. SETTING: A single university hospital. PARTICIPANTS: This study included 24 patients undergoing aortic arch surgery with cardiopulmonary bypass (CPB) using antegrade selective cerebral perfusion (SCP). INTERVENTIONS: Measurement of optic nerve head blood flow using LSFG and radial arterial pressure via a catheter in the radial artery METHODS AND MAIN RESULTS: Antegrade SCP was managed with 24℃ and 40-to-60 mmHg at the right radial artery, which usually corresponds to a flow rate of 10 mL/kg/min. Optic nerve head blood flow using LSFG and radial arterial blood pressure were evaluated simultaneously at the right side and recorded at the following 4 points: after the induction of anesthesia (phase 1), after the beginning of CPB (phase 2), after the beginning of antegrade SCP (phase 3), and after cessation of CPB (phase 4). A moderate positive correlation between %change of mean blur rate in the optic nerve head measured using LSFG and %change of radial mean arterial pressure was identified (r = 0.604, p < 0.001). Bland-Altman analysis showed that the bias (mean difference) was -1.2% (95% limits of agreement -47.4% to 45.0%), indicating good agreement between %changes of the values recorded using the 2 measurements. CONCLUSIONS: Intraoperative monitoring of optic nerve head blood flow using LSFG can be used as an additional cerebral perfusion parameter during aortic arch surgery with CPB using antegrade SCP.

Pregnancy in women with corrected aortic coarctation: Uteroplacental Doppler flow and pregnancy outcome.

OBJECTIVE: Women with repaired coarctation of the aorta (rCoA) are at risk of hypertensive disorders and other complications during pregnancy. Hypertensive disorders in pregnant women are associated with inadequate uteroplacental flow, which is related to adverse offspring outcome. The aim of this study was to investigate the relationship of maternal cardiac function, placental function and pregnancy complications in women with rCoA. METHODS: We included 49 pregnant women with rCoA and 69 controls from the prospective ZAHARA-studies (Zwangerschap bij Aangeboren HARtAfwijkingen, pregnancy in congenital heart disease). Clinical evaluation, echocardiography and uteroplacental Doppler flow (UDF) measurements were performed at 20 and 32weeks gestation. Univariable regression analysis was performed. RESULTS: Comparison of rCoA and healthy women. In women with rCoA, tricuspid annular plane systolic excursion (TAPSE) decreased during pregnancy (25.7mm to 22.8mm, P=0.006). UDF indices and pregnancy complication rates were similar in both groups. Offspring of rCoA women had lower birth weight (3233g versus 3578g, P=0.001), which was associated with ß-blocker use during pregnancy (ß=-418.0, P=0.01). Association of cardiac function and UDF. Right ventricular (RV) function before pregnancy (TAPSE) and at 20weeks gestation (TAPSE and RV fractional area change) were associated with impaired UDF indices (umbilical artery pulsatility index at 20weeks ß=-0.02, P=0.01, resistance index at 20 and 32weeks ß=-0.01, P=0.02 and ß=-0.02, P=0.01 and uterine artery pulsatility and resistance index at 20weeks gestation ß=-0.02, P=0.05 and ß=-0.01, P=0.02). CONCLUSIONS: Women with rCoA tolerate pregnancy well. However, RV function is altered and is associated with impaired placentation.

Láser Doppler y su uso en odontología / Laser Doppler and its use in dentistry

El efecto Doppler es la base científica de la flujometría láser Doppler. El efecto fue descrito por primera vez en el año de 1842 por el físico austriaco Christian Doppler en su tratado Über das farbige licht der doppelsterne und einige andere gestirne des himmels (Sobre el color de la luz en estrellas binarias y otros astros). Este principio ha permitido desarrollar técnicas y aparatos que han sido empleados en el ramo médico para medir la perfusión en diversos órganos y tejidos del cuerpo, y que han sido útiles como método diagnóstico. En la odontología, poco a poco comienza a reportarse información acerca del uso del Doppler en las diversas estructuras bucodentales, y ha demostrado ser no invasivo y de gran utilidad diagnóstica. Son pocos los estudios reportados en la rama de la odontología en cuanto a esta nueva tecnología; es importante comenzar líneas de investigación apoyadas en ella para beneficio de los pacientes.

The Doppler eff ect, the scientifi c basis of laser Doppler fl owmetry, wasfi rst described in 1842 by Austrian physicist Christian Doppler in histreatise Über das farbige Licht der doppelsterne und einige andere gestirnedes Himmels (On the Colored Light of the Binary Stars and SomeOther Stars of the Heavens). This principle has led to the developmentof techniques and devices that have been used in the fi eld of medicineto measure perfusion in various organs and tissues, and have provideda useful method of diagnosis. In dentistry, information on the use ofthis method in the various structures of the mouth has slowly begunto be published. As a result, the need for its continued use in the fi eldof oral health has become evident, given that it has proven to be noninvasiveand extremely useful in diagnosis. It is a diagnostic technique that is commonly used in healthcare and has been widely developedin the fi eld of medicine, yet there have been few reported studies of it suse in dentistry, which is an important step towards opening new linesof research based on this new technology for the benefi t of patients.

Terapia hemodinámica guiada por objetivos basada en parámetros de flujo con Doppler esofágico: revisión sistemática, metaanálisis y análisis secuencial de ensayos / Goal directed hemodynamic therapy based in esophageal Doppler flow parameters: a systematic review, meta-analysis and trial sequential analysis

Introducción. Numerosos estudios han comparado la monitorización perioperatoria guiada por Doppler esofágico (ODM) para establecer estrategias de reemplazo de volumen intravascular. El uso del ODM con algoritmos hemodinámicos se denomina terapia hemodinámica guiada por objetivos (THGO). Métodos. Metaanálisis de los efectos del ODM en THGO para cirugía no cardiaca de adultos, las complicaciones postoperatorias y la mortalidad, acorde a PRISMA. Se practicó búsqueda sistemática en Medline, PubMed, EMBASE y la Cochrane Library (última actualización, marzo de 2015). Criterios de inclusión: ensayos clínicos aleatorizados (ECA) que comparan THGO con otra alternativa de manejo de fluidos. Desenlaces primarios: complicaciones generales. Desenlaces secundarios: mortalidad; número de pacientes con complicaciones; complicaciones específicas. Se realizó análisis cuantificable, análisis predefinido de subgrupos y sensibilidad, y análisis secuencial de estudios. Resultados. Se identificaron inicialmente 56 ECA, siendo finalmente admitidos para el estudio 15 (1.368 pacientes). Se observó una reducción significativa global, con THGO, de las complicaciones asociadas comparada con fluidoterapia convencional (RR=0,75; IC95%: 0,63-0,89; p=0,0009), en cirugía colorrectal, urológica y de alto riesgo No se encontraron diferencias en los resultados secundarios, ni en otros subgrupos. El impacto en la prevención de complicaciones en pacientes con ODM es alto, con una reducción del riesgo relativo (RRR) del 50% y un número necesario a tratar (NNT)=6. Conclusiones. La THGO guiada por ODM disminuye las complicaciones postoperatorias, principalmente en pacientes sometidos a cirugía colorrectal y de alto riesgo. No se encontraron diferencias con respecto a la fluidoterapia restrictiva y en pacientes de riesgo intermedio (AU)

Background. Numerous studies have compared perioperative esophageal doppler monitoring (EDM) guided intravascular volume replacement strategies with conventional clinical volume replacement in surgical patients. The use of the EDM within hemodynamic algorithms is called ‘goal directed hemodynamic therapy’ (GDHT). Methods. Meta-analysis of the effects of EDM guided GDHT in adult non-cardiac surgery on postoperative complications and mortality using PRISMA methodology. A systematic search was performed in Medline, PubMed, EMBASE, and the Cochrane Library (last update, March 2015). Inclusion criteria: Randomized clinical trials (RCTs) in which perioperative GDHT was compared to other fluid management. Primary outcomes: Overall complications. Secondary outcomes: Mortality; number of patients with complications; cardiac, renal and infectious complications; incidence of ileus. Studies were subjected to quantifiable analysis, pre-defined subgroup analysis (stratified by surgery, type of comparator and risk); pre-defined sensitivity analysis and trial sequential analysis (TSA). Results. Fifty six RCTs were initially identified, 15 fulfilling the inclusion criteria, including 1,368 patients. A significant reduction was observed in overall complications associated with GDHT compared to other fluid therapy (RR=0.75; 95%CI: 0.63-0.89; P=0.0009) in colorectal, urological and high-risk surgery compared to conventional fluid therapy. No differences were found in secondary outcomes, neither in other subgroups. The impact on preventing the development of complications in patients using EDM is high, causing a relative risk reduction (RRR) of 50% for a number needed to treat (NNT)=6. Conclusions. GDHT guided by EDM decreases postoperative complications, especially in patients undergoing colorectal surgery and high-risk surgery. However, no differences versus restrictive fluid therapy and in intermediate-risk patients were found (AU)

Looking for complementary alternatives to CTCAE for skin toxicity in radiotherapy: quantitative determinations

INTRODUCTION: Radiotherapy (RT) is an essential part of the patient's treatment diagnosed with cancer. Determination of the most common RT secondary effect, the cutaneous toxicity, is usually based on visual rating scales, like Common Terminology Criteria for Adverse Events with an inherent subjectivity. The aim of this work is to perform an objective method to evaluate the radiodermatitis using a non-invasive imaging technique based on laser Doppler flowmetry (LDF). MATERIALS AND METHODS: A prospective study was performed analysing 1,824 measurements. A LDF was used to measure the cutaneous microcirculation in real time. A basal measurement was taken prior to radiotherapy treatment. To be able to observe the microcirculation changes related to the delivered dose, several sets of measurements were taken in the irradiated area along the RT treatment and in the contralateral non-irradiated area. RESULTS: A relative increase in blood flow at all measured points was found in the irradiated area. This relative increase in blood flow increases with the dose administered. In the non-irradiated contralateral area, the relative increase in blood flow is not significant and is independent of the dose administered. After treatment, a decrease in blood flow was detected with a trend towards returning to the baseline measurements. CONCLUSIONS: LDF is an objective technique that assesses early radiodermatitis. This method is useful to develop strategies to prevent onset of radiation dermatitis in patients irradiated, such as the modification and individualization of fractionation parameters of the RT. This allows the reduction of radiation morbidities and maintains patient quality of life (AU)

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Constricción prematura del ductus arterioso: consecuencias del consumo excesivo de té negro y de hierbas / Premature ductus arteriosus constriction: consequences of excess maternal consumption of herbal and black tea

La constricción intrauterina del ductus arterioso es un evento raro, que a menudo resulta en una grave morbilidad fetal/neonatal y en mortalidad. La constricción del ductus fetal surge generalmente asociada a la exposición materna a los antiinflamatorios no esteroideos o a lesiones estructurales cardíacas. El pronóstico depende del grado y el intervalo de la obstrucción del flujo ductal. Para identificar la causa detrás de este diagnóstico se requiere generalmente la realización de una anamnesis detallada. En este artículo presentamos 2 casos de fetos con constricción del ductus arterioso diagnosticados por ecocardiografía rutinaria del tercer trimestre. El consumo excesivo de té negro y de hierbas fue identificado como la causa de la constricción del ductus arterioso. Alrededor de 2 semanas después de interrumpir el consumo de dichas sustancias, la constricción ductal se invirtió y los valores hemodinámicos han vuelto a la normalidad. Las mujeres embarazadas y los médicos deben ser sensibles a los efectos de los consumos en exceso de alimentos con altas concentraciones de polifenoles(AU)

Intrauterine constriction of ductus arteriosus is a rare event which often results in severe fetal/neonatal morbidity and mortality. Fetal ductus constriction is usually associated with maternal exposure to non-steroidal anti-inflammatory drugs or structural cardiac lesions. The prognosis depends on the degree and interval of ductal flow obstruction. Detailed history taking is generally required to identify the cause of this diagnosis. We report two cases of fetuses with ductus arterious constriction diagnosed by routine echocardiography in the third- trimester. The cause of the ductus arterious constriction was identified as excess consumption of black and herbal tea. Around 2 weeks after stopping consumption of these substances, ductal constriction was reversed and hemodynamic values returned to normal. Pregnant women and clinicians should be sensitized to the effects of excess consumptions of foods with high concentrations of polyphenol(AU)

Valoración con termografía infrarrojo, de la capacidad vasodilatadora de las diferentes corrientes analgésicas y factores implicados / Assessment of the vasodilatory capacity of different analgesic currents using infrared thermography

Objetivos. Primero, hacer una valoración cuantitativa, mediante termografía infrarrojo (TIR) del proceso de vasodilatación provocado por las corrientes analgésicas; segundo, valorar las diferencias entre ellas, y tercero, comprobar si la vasodilatación es debida al efecto Joule o existen otros mecanismos. Material y método. Incluidos 12 individuos (6 mujeres y 6 varones); edades comprendidas entre los 23 y 47 años (media 34 años y 4 meses) y estudio de TIR, previo al tratamiento, normal. En todos se hizo una valoración con TIR de su columna vertebral, al inicio, después del tratamiento y a los 30 y 60 minutos de finalizado. Corrientes valoradas: bifásica compensada, interferencial, ultraexcitante y diadinámica. Resultados. Tras finalizar el tratamiento aparecía una zona de hiperemia debajo de los electrodos con gradiente de temperatura de +3,7°C±0,82°C (p<0,001), respecto de la inicial. En las zonas interpolares, hiperemia inapreciable, pero con gradiente térmico de +0,9°C±0,2°C (p<0,05). A los 30 y 60 minutos desaparición de la hiperemia local, extendiéndose por la espalda y con gradiente de temperatura a la hora de +1,3°C±0,03°C (p<0,05). Conclusiones. Las corrientes analgésicas provocan una vasodilatación en las zonas polares (mayor en el cátodo en las corrientes monofásicas), que decrece progresivamente y se extiende por toda la región interpolar. No existen diferencias manifiestas a la hora entre las diferentes corrientes. Pueden existir otros mecanismos vasodilatadores además del efecto Joule (AU)

Objectives. To make a quantitative assessment, using infrared thermography (IRT) of the vasodilation process induced by different analgesic currents, and to assess the differences between them. It will also be determined whether the vasodilation is due to the Joule effect or whether there are other mechanisms. Materials and methods. The study included 12 subjects (6 men and 6 women), with an age range of 23-47 years (mean 34 years and 4 months) and who were assessed by infrared thermography prior to the normal treatment. An assessment with infrared thermography of the spinal column was performed on all of them, at the beginning, after treatment and at 30 and 60minutes after the treatment was finished. The currents assessed were, biphasic, interferential, ultra-excitatory and diadynamic. Results. After finishing the treatment an area of hyperaemia appeared beneath the electrodes using a temperature gradient of 3.7°C±0.82°C (P<0.001) from the baseline. Negligible hyperaemia was observed in the interpolar zones with temperature gradient of 0.9°C±0.2°C (P<0.05). At 30 and 60minutes, the local hyperaemia disappeared, being extended across the back and with a temperature gradient at one hour of 1.3°C±0.03°C (P<0.05). Conclusions. Analgesic currents produce vasodilation in the polar areas (higher in the cathode in single-phase currents) that gradually decreases and extends throughout the interpolar area. There are no significant differences between the currents at one hour. There may be other vasodilatory mechanisms as well as the Joule effect (AU)

V.1. Ultrasound imaging and Doppler flow velocity measurement.

High frequency ultrasound (2 - 8 MHz typically) has established itself as a major medical imaging method associated with a wide range of clinical applications. Advantages include real-time applicability, lower cost compared with other medical imaging technologies, possibility of measuring blood flow velocities and desk-top instrumentation. Disadvantage is associated with lower image quality than is obtained with x-ray or magnetic resonance methods.

Principles and practice of the laser-Doppler perfusion technique.

This paper reviews the development and use of laser-Doppler perfusion monitors and imagers over the past two decades. The enormous interest in microvascular blood perfusion coupled with the 'ease of use' of the technique has led to 1500+ publications citing its use. However, useful results can only be achieved with an understanding of the basic principles of the instrumentation and its application in the various clinical disciplines. The basic theoretical background is explored and definitions of blood perfusion and laser-Doppler perfusion are established. The calibration method is then described together with potential routes to standardisation. A guide to the limitations in application of the technique gives the user a clear indication of what can be achieved in new studies as well as possible inadequacy in some published investigations.

A method of endoscopic investigation of vascular structures directly through flowing blood.

BACKGROUND: Noninvasive cardiovascular diagnosis has improved immensely due to key technological refinements such as digital subtraction angiography, ultrasonography, Doppler flow analysis, and magnetic resonance imaging. Each of these methodologies provides a unique image of the cardiovascular system but will not permit surgical maneuvers or repairs during real time imaging. Our group has developed a new method of endoscopic visualization of the luminal surface of blood vessels directly through flowing blood without interference of the blood or vessel wall. This opens new possibilities in both diagnosis and surgical interventions. METHODS: Transluminal imaging through flowing blood was performed in normal animals using laser frequency light delivered and retrieved via conventional fiberoptic angioscopic instruments. The reflected light energy was reconstructed into a viewable image using a specialized method of optical data processing and filtering systems. Unlike conventional angioscopy, displacement of flowing blood was not needed as the images were obtained with higher frequency laser light. RESULTS: A total of 20 canine experiments were performed between 1996 and 1997 using our endoluminal imaging system. The images obtained revealed details of luminal surfaces, although primitive and low resolution with this first generation of technology. Images of the topography of the femoral, axillary, and subclavian arteries and veins, as well as several intracardiac structures (aorta and aortic valve) were successfully obtained without trauma or physiologic consequence to the animal. CONCLUSIONS: Using conventional fiberoptic angioscopes coupled with laser light of differing wavelengths, it was possible to image the interior of vascular structures through flowing blood. This method visualizes the intraluminal surface in real time and is dependent only on the delivery and capacity of the endoscope. The implications for future cardiovascular diagnosis and corrective surgical procedures are widespread.