The efficacy of esmolol, remifentanil and nitroglycerin in controlled hypotension for functional endoscopic sinus surgery / Eficácia do esmolol, remifentanil e nitroglicerina na hipotensão controlada para cirurgia sinusal endoscópica funcional

Abstract Introduction Controlled hypotension is a reversible procedure in which the patient's baseline mean arterial blood pressure is reduced by 30% and sustained at 60-70 mmHg during the procedure. It decreases blood loss and provides clear surgical field during the procedures. Objectives The purpose of this study was to compare the efficacy of controlled hypotension agents esmolol, remifentanil, and nitroglycerin in functional endoscopic sinus surgery, in terms of hemodynamic changes and impact on the surgical efficiency. Methods The research was carried out as a cohort study. Patients who underwent functional endoscopic sinus surgery were randomized into 3 groups. Controlled hypotension was achieved with remifentanil (Group R), esmolol (Group E) and nitroglycerin (Group N). The efficacy of the drugs was tested by comparing the length of time with the targeted mean arterial pressure, the amount of anesthetics used, surgical field bleeding score and surgeon's satisfaction. Results Between May to December 2015, 60 patients were included and randomized equally into 3 different study groups. The median of the length of time with the targeted mean arterial pressure was shorter in the Group R when compared with Group E (p = 0.01) and Group N (p = 0.14). The amount of volatile anesthetics used was 25.0 mL (15-51), 43.0 mL (21-105) and 40.0 mL (26-97) in Groups R, E and N, respectively (p < 0.001). While there was more bleeding with nitroglycerin, surgical field bleeding scores were lower in Group R when compared with esmolol (p = 0.001) and nitroglycerin (p < 0.001). The analysis of surgeon's satisfaction scores concluded that surgeons were more satisfied with the group R (100%), when compared with group E (60%) and group N (30%) (p < 0.001). Conclusion Less volatile agent, short time to achieve controlled hypotension, stable blood pressure, lower surgical field bleeding scores and larger length of time with the targeted mean arterial pressure were found as the advantages of Remifentanil. Less costly, efficiency of achieving the targeted median arterial pressure and less postoperative complications were the advantages of nitroglycerin. In functional endoscopic sinus surgery procedures, appropriate controlled hypotensive agents should be selected according to the patients' characteristics and advantages/disadvantages of the drugs.

Resumo Introdução Hipotensão controlada é um procedimento reversível no qual a pressão arterial média basal do paciente é reduzida em 30% e mantida em 60-70 mmHg durante o procedimento. Isso diminui a perda de sangue e propicia um campo cirúrgico limpo durante os procedimentos. Objetivo Comparar agentes usados para hipotensão controlada: esmolol, remifentanil e nitroglicerina em cirurgia sinusal endoscópica funcional, em termos de alterações hemodinâmicas e impactos na eficácia cirúrgica. Método O estudo foi feito como de coorte. Pacientes submetidos à cirurgia sinusal endoscópica funcional foram randomizados em 3 grupos. A hipotensão controlada foi feita com remifentanil (Grupo R), esmolol (Grupo E) e nitroglicerina (Grupo R). A eficácia dos medicamentos foi testada com a comparação do período de tempo com a pressão arterial média desejada, a quantidade de anestésicos usados, o escore de sangramento no campo cirúrgico e a satisfação do cirurgião. Resultados Entre maio e dezembro de 2015, 60 pacientes foram incluídos e randomizados igualmente nos três grupos de estudo. A mediana do período com a pressão arterial desejada foi menor no Grupo R quando comparado ao Grupo E (p = 0,01) e Grupo N (p = 0,14). A quantidade de anestésicos voláteis usados foi de 25,0 mL (15 ± 51), 43,0 mL (21 ± 105) e 40,0 mL (26 ± 97) nos Grupos R, E e N, respectivamente (p < 0,001). Houve mais sangramento com nitroglicerina e escores de sangramento no campo cirúrgico foram menores no Grupo R quando comparados com esmolol (p = 0,001) e nitroglicerina (p < 0,001). A análise dos escores da satisfação do cirurgião concluiu que os cirurgiões estavam mais satisfeitos com o grupo R (100%) quando comparados ao grupo E (60%) e o grupo N (30%) (p < 0,001). Conclusão Agente menos volátil, pouco tempo para obter a hipotensão controlada, pressão arterial estável, menor escore de sangramento no campo cirúrgico e período de pressão arterial desejada curto foram considerados como vantagens do remifentanil. Menor custo, eficácia de obtenção da pressão arterial média desejada e menos complicações pós-operatórias foram as vantagens da nitroglicerina. Nos procedimentos de cirurgia sinusal endoscópica funcional, os agentes apropriados para obtenção de hipotensão controlada devem ser selecionados de acordo com as características dos pacientes e as vantagens/desvantagens dos fármacos.

Damage control resuscitation: REBOA as the new fourth pillar / Resucitación en control de daños: REBOA, el cuarto pilar

Abstract Damage Control Resuscitation (DCR) seeks to combat metabolic decompensation of the severely injured trauma patient by battling on three major fronts: Permissive Hypotension, Hemostatic Resuscitation, and Damage Control Surgery (DCS). The aim of this article is to perform a review of the history of DCR/DCS and to propose a new paradigm that has emerged from the recent advancements in endovascular technology: The Resuscitative Balloon Occlusion of the Aorta (REBOA). Thanks to the advances in technology, a bridge has been created between Pre-hospital Management and the Control of Bleeding described in Stage I of DCS which is the inclusion and placement of a REBOA. We have been able to show that REBOA is not only a tool that aids in the control of hemorrhage, it is also a vital tool in the hemodynamic resuscitation of a severely injured blunt and/or penetrating trauma patient. That is why we propose a new paradigm "The Fourth Pillar": Permissive Hypotension, Hemostatic Resuscitation, Damage Control Surgery and REBOA.

Resumen La resucitación en control de daños busca combatir la descompensación metabólica del paciente severamente traumatizado mediante tres ejes: la hipotensión permisiva, la resucitación hemostática y la cirugía de control de daños. El objetivo de este artículo es hacer una revisión de la historia de la resucitación en control de daños y la cirugía de control de daños proponiendo un nuevo paradigma basado en los recientes avances de la tecnología endovascular. Un puente ha sido creado entre el manejo prehospitalario y el control del sangrado, descrito antes de la etapa I de la cirugía de control de daños, que es la inclusión y colocación de un REBOA. Esta es una herramienta adicional en el control de la hemorragia y de soporte en la resucitación hemodinámica de los pacientes con trauma severo de tipo cerrado y/o penetrante. Por lo que se propone un nuevo paradigma "El cuarto pilar": Hipotensión permisiva, resucitación hemostática, cirugía de control de daños y REBOA.

Hipotensión controlada en cirugía espinal / Controlled Hypotension in Spinal Surgery

RESUMEN Introducción: La hipotensión controlada implica a cualquier técnica que, utilizada de forma única o combinada, disminuya intencionalmente los valores de tensión arterial durante el período intraoperatorio, con la finalidad de reducir el sangramiento y mejorar la visibilidad del campo quirúrgico. Objetivo: Describir los fundamentos fisiológicos, definiciones, técnicas y complicaciones de la hipotensión controlada aplicada en la cirugía espinal. Métodos: Se realizó una revisión de la literatura, en bases de datos científicas como Cochrane Database of Systematic Reviews, Pubmed/Medline, EMBASE, SCOPUS, Web of Science, Ebsco Host, ScienceDirect, OVID y el buscador académico Google Scholar, en el mes de junio del 2020. Conclusiones: La hipotensión controlada aplicada en la cirugía espinal presenta limitados beneficios quirúrgicos. Sin embargo, no existe un consenso preciso sobre los umbrales hemodinámicos y límites de tiempo requeridos para su utilización, y se asocia a un elevado riesgo de potenciales complicaciones como el delirium, disfunción cognitiva posoperatoria, accidente cerebrovascular isquémico, pérdida visual posoperatoria, lesión renal aguda, lesión miocárdica, déficit neurológico posoperatorio tardío y dolor neuropático crónico; por lo cual no se recomienda su empleo rutinario durante el período intraoperatorio(AU)

ABSTRACT Introduction: Controlled hypotension implies any technique that, used alone or in combination, intentionally lowers blood pressure values during the intraoperative period, in order to reduce bleeding and improve the visibility of the surgical field. Objective: To describe the physiological foundations, definitions, techniques and complications of controlled hypotension in spinal surgery. Methods: A literature review was carried out in scientific databases such as Cochrane Database of Systematic Reviews, Pubmed/Medline, EMBASE, SCOPUS, Web of Science, Ebsco Host, ScienceDirect, OVID and the academic search engine Google Scholar, in June 2020. Conclusion: Controlled hypotension in spinal surgery has limited surgical benefits. However, there is no precise consensus on the hemodynamic thresholds and time limits required for its use, and it is associated with a high risk of potential complications as delirium, postoperative cognitive dysfunction, ischemic stroke, postoperative visual loss, acute kidney injury, myocardial injury, late postoperative neurological deficit and chronic neuropathic pain; therefore, its routine use during the intraoperative period is not recommended(AU)

Comparison of dexmedetomidine versus propofol-based anaesthesia for controlled hypotension in functional endoscopic sinus surgery

Background: Increased intraoperative bleeding during functional endoscopic sinus surgery (FESS) affects operative field visibility, which increases both duration of surgery and frequency of complications. Controlled hypotension is an anaesthetic technique in which there is deliberate reduction of systemic blood pressure during anaesthesia. The aim of the study was to compare the efficacy of dexmedetomidine against propofol infusion when used for controlled hypotension during FESS. Methods: A randomised, prospective, and single-blinded study was carried out, which included 80 patients of either sex of ASA grade І & ІІ who underwent elective FESS. Patients were randomly assigned to two groups: Group A (dexmedetomidine), Group B (propofol). Intraoperative mean arterial pressure (MAP), heart rate (HR), surgical grade of bleeding (based on the Fromme­ Boezzart scale), and amount of bleeding were recorded. Results: Groups were well matched for their demographic data. There was a statistically significant difference (p < 0.05) between Group A and Group B in heart rate, mean arterial pressure (MAP) and mean total blood loss, with Group A being effectively in controlled on all three parameters during FESS. However, there was no significant difference (p > 0.05) in terms of surgical grade of bleeding between Group A and Group B. Conclusions: Both dexmedetomidine and propofol infusion are efficacious to facilitate controlled hypotension and haemodynamic stability intraoperatively

Damage control resuscitation in children

Damage control resuscitation is a relatively new resuscitative strategy for patients with severe traumatic hemorrhage. This strategy consists of permissive hypotension and early balanced transfusion, and transfers the patients to subsequent surgery. There is growing evidence on harms of excessive fluids. Since 2013, survival benefit of massive transfusion protocol has been proven in adults. Despite insufficient evidence, pediatric massive transfusion protocols are widely used in North American trauma centers. This review focuses on the concept of damage control resuscitation, and summarizes the relevant pediatric evidence.

Efficacy of minimal invasive cardiac output and ScVO₂ monitoring during controlled hypotension for double-jaw surgery

BACKGROUND: Controlled hypotension (CH) provides a better surgical environment and reduces operative time. However, there are some risks related to organ hypoperfusion. The EV1000/FloTrac system can provide continuous cardiac output monitoring without the insertion of pulmonary arterial catheter. The present study investigated the efficacy of this device in double jaw surgery under CH.METHODS: We retrospectively reviewed the medical records of patients who underwent double jaw surgery between 2010 and 2015. Patients were administered conventional general anesthesia with desflurane; CH was performed with remifentanil infusion and monitored with an invasive radial arterial pressure monitor or the EV1000/FloTrac system. We allocated the patients into two groups, namely an A-line group and an EV1000 group, according to the monitoring methods used, and the study variables were compared.RESULTS: Eighty-five patients were reviewed. The A-line group reported a higher number of failed CH (P = 0.005). A significant correlation was found between preoperative hemoglobin and intraoperative packed red blood cell transfusion (r = 0.525; P < 0.001). In the EV1000 group, the mean arterial pressure (MAP) was significantly lower 2 h after CH (P = 0.014), and the cardiac index significantly decreased 1 h after CH (P = 0.001) and 2 h after CH (P = 0.007). Moreover, venous oxygen saturation (ScVO2) decreased significantly at both 1 h (P = 0.002) and 2 h after CH (P = 0.029); however, these values were within normal limits.CONCLUSION: The EV1000 group reported a lower failure rate of CH than the A-line group. However, EV1000/FloTrac monitoring did not present with any specific advantage over the conventional arterial line monitoring when CH was performed with the same protocol and same mean blood pressure. Preoperative anemia treatment will be helpful to decrease intraoperative transfusion. Furthermore, ScVO2 monitoring did not present with sufficient benefits over the risk and cost.

Effect of controlled hypotension on predicting transfusion response and threshold of stroke variability in hypertensive patients undergoing robotic hepatobiliary surgery / 中南大学学报(医学版)

To investigate the effect of controlled hypotension by urapidil on the predictive accuracy and diagnostic threshold of stroke volume variation (SVV) in hypertensive and non-hypertensive patients undergoing robotic hepatobiliary surgery.
 Methods: Eighty patients undergoing robotic hepatobiliary surgery under general anesthesia were divided into a hypertension group (n=25) and a non-hypertension group (n=38) according to whether or not essential hypertension was present (excluding some cases that didn't meet requirements). The pump speed was at 6.0-7.0 µg/(kg﹒min), and the range of hypotension was between 10%≤Δ systolic blood pressure (SAP)≤20%. Volume loading test was performed after artificial pneumoperitoneum was established in reverse-Trendelenburg position. Hemodynamic indexes including heart rate (HR), SAP, cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke volume index (SVI) and SVV were recorded before and after infusion. Then the receiver operating characteristic (ROC) curves of SVV was drawn to determine the accuracy and diagnosis of SVV in predicting volume status in hypertensive and non-hypertensive patients after anti-Trendelenburg posture and pneumoperitoneum.
 Results: In the patients with controlled hypotension by urapidil, the area under the ROC curve of SVV in the hypertension group was 0.974, the diagnostic threshold was 13.5%, the ROC curve of SVV in the non-hypertension group was 0.832, and the diagnostic threshold was 15.5%.
 Conclusion: SVV can accurately predict the volume status in the hypertension group and the non-hypertension group after controlled hypotension in the anti-Trendelenburg position and fixed pneumoperitoneal pressure, and the SVV diagnostic threshold in the non-hypertensive group is higher than that in the hypertensive group.

Abordagem PK-PD do propofol na revascularização do miocárdio para estudo da influência da circulação extracorpórea na ligação às proteínas plasmáticas e no efeito hipnótico / PK-PD Model to investigate the free propofol plasma levels versus the hypnotic drug effect in patients undergoing coronary artery bypass grafting concerning the influence of CPB-hypothermia on drug plasma binding

Durante a cirurgia de revascularização do miocárdio com circulação extracorpórea e hipotermia (CEC-H) ocorre alteração na efetividade do propofol e na sua farmacocinética realizada a partir das concentrações plasmáticas do propofol total no decurso do tempo. A ligação do propofol à proteína plasmática parece estar alterada em consequência de diversos fatores incluindo a hemodiluição e a heparinização que ocorre no início da circulação extracorpórea, uma vez que se reportou anteriormente que a concentração plasmática do propofol livre aumentou durante a realização da circulação extracorpórea normotérmica. Por outro lado, a infusão alvo controlada é recomendada para manter a concentração plasmática do propofol equivalente ao alvo de 2 µg/mL durante a intervenção cirúrgica com CEC-H. Se alterações significativas na hipnose do propofol ocorrem nesses pacientes, então o efeito aumentado desse agente hipnótico poderia estar relacionado à redução na extensão da ligação do fármaco as proteínas plasmáticas; entretanto, o assunto ainda permanece em discussão e necessita de investigações adicionais. Assim, o objetivo do estudo foi investigar as concentrações plasmáticas de propofol livre em pacientes durante a revascularização do miocárdio com e sem o procedimento de CEC-H através da abordagem PK-PD. Dezenove pacientes foram alocados e estratificados para realização de cirurgia de revascularização do miocárdio com circulação extracorpórea (CEC-H, n=10) ou sem circulação extracorpórea (NCEC, n=9). Os pacientes foram anestesiados com sufentanil e propofol alvo de 2 µg/mL. Realizou-se coleta seriada de sangue para estudo farmacocinético e o efeito foi monitorado através do índice bispectral (BIS) para medida da profundidade da hipnose no período desde a indução da anestesia até 12 horas após o término da infusão de propofol, em intervalos de tempo pré-determinados no protocolo de estudo. As concentrações plasmáticas foram determinadas através de método bioanalítico pela técnica de cromatografia líquida de alta eficiência. A farmacocinética foi investigada a partir da aplicação do modelo aberto de dois compartimentos, PK Solutions v. 2. A análise PK-PD foi realizada no Graph Pad Prisma v.5.0 após a escolha do modelo do efeito máximo (EMAX sigmóide, slope variável). Os dados foram analisados utilizando o Prisma v. 5.0, p<0,05, significância estatística. As concentrações plasmáticas de propofol total foram comparáveis nos dois grupos (CEC-H e NCEC); entretanto o grupo CEC-H evidenciou aumento na concentração do propofol livre de 2 a 5 vezes em função da redução na ligação do fármaco às proteínas plasmáticas. A farmacocinética do propofol livre mostrou diferença significativa entre os grupos no processo de distribuição pelo prolongamento da meia vida e aumento do volume aparente, e no processo de eliminação em função do aumento na depuração plasmática e redução na meia vida biológica no grupo CEC-H. A escolha do modelo EMAX sigmóide, slope variável foi adequada uma vez que se evidenciou alta correlação entre os valores do índice bispectral e as concentrações plasmáticas do propofol livre (r2>0.90, P<0.001) para os pacientes investigados

During coronary artery bypass grafting (CABG) surgery with cardiopulmonary bypass (CPB) profound changes occur on propofol effect and on kinetic disposition related to total drug plasma measurements in these patients. It was reported that drug plasma binding could be altered as a consequence of hemodilution and heparinization before starts CPB since free propofol plasma levels was increased by twice under normothermic procedure. In addition, the target controlled infusion (TCI) is recommended to maintain propofol plasma concentration (2 µg/mL) during CABG CPB-H intervention. However, whether significant changes that occur in propofol hypnosis in these patients could be related to the reduction on the extension of drug plasma binding remain unclear and under discussion until now. Then, the objective of this study was to investigate propofol free plasma levels in patients undergoing CABG with and without CPB by a pharmacokinetics-pharmacodynamics (PK-PD) approach. Nineteen patients were scheduled for on-pump coronary artery bypass grafting (CABG-CPB, n=10) or off-pump coronary artery bypass grafting (OPCABG, n=9) were anesthetized with sufentanil and propofol TCI (2 µg/mL). Blood samples were collected for drug plasma measurements and BIS were applied to access the depth of hypnosis from the induction of anesthesia up to 12 hours after the end of propofol infusion, at predetermined intervals. Plasma drug concentrations were measured using high-performance liquid chromatography, followed by a propofol pharmacokinetic analysis based on two compartment open model, PK Solutions v.2; PK-PD analysis was performed by applying EMAX model, sigmoid shape-variable slope and data were analyzed using Prisma v. 5.0, considering p<0.05 as significant difference between groups. The total propofol plasma concentrations were comparable in both groups during CABG; however it was shown in CPB-group significant increases in propofol free plasma concentration by twice to fivefold occur as a consequence of drug plasma protein binding reduced in these patients. Pharmacokinetics of free propofol in CPB-H group compared to OPCAB group based on two compartment open model was significantly different by the prolongation of distribution half-life, increases on plasma clearance, and biological half-life shortened. In addition, the kinetic disposition of propofol changes in a different manner considering free drug levels in the CPB-H group against OPCAB group as follows: prolongation of distribution half-life and increases on volume of distribution, remaining unchanged biological half-life in spite of plasma clearance increased. BIS values showed a strong correlation with free drug levels (r2>0.90, P<0.001) in CPB-H group and also in OPCAB group by the chosen EMAX model sigmoid shape-variable slope analyzed by GraphPad Prisma v.5.0

Comparison between magnesium sulfate and dexmedetomidine in controlled hypotension during functional endoscopic sinus surgery / Comparação entre dexmedetomidina e sulfato de magnésio em hipotensão controlada durante cirurgia funcional endoscópica dos seios paranasais / Comparación entre el sulfato de magnesio y la dexmedetomidina en hipotensión controlada durante cirugía funcional endoscópica de los senos paranasales

BACKGROUND AND OBJECTIVES: It is crucial to decrease bleeding during functional endoscopic sinus surgery. Our primary goal was to investigate the effects of magnesium sulfate and dexmedetomidine used for controlled hypotension on the visibility of the surgical site. METHODS: 60 patients aged between 18 and 65 years were enrolled. In the magnesium sulfate group (Group M), patients were administered 40 mg/kg magnesium sulfate in 100 mL saline solution over 10 min as the intravenous loading dose 10 min before induction, with a subsequent 10-15 µg/kg/h infusion during surgery. In the dexmedetomidine group (Group D), patients were administered 1 µg/kg dexmedetomidine in 100 mL saline solution as the loading dose 10 min before surgery and 0.5-1 µg/kg/h dexmedetomidine during surgery. Deliberate hypotension was defined as a mean arterial pressure of 60-70 mmHg. RESULTS: Bleeding score was significantly decreased in Group D (p = 0.002). Mean arterial pressure values were significantly decreased in Group D compared to that in Group M, except for the initial stage, after induction and 5 min after intubation (p < 0.05). The number of patients who required nitroglycerine was significantly lower in Group D (p = 0.01) and surgeon satisfaction was significantly increased in the same group (p = 0.001). Aldrete recovery score ≥9 duration was significantly shorter in Group D (p = 0.001). There was no difference between the two groups in terms of recovery room verbal numerical rating scale. CONCLUSIONS: Dexmedetomidine can provide more effective controlled hypotension and thus contribute to improved visibility of the surgical site. .

JUSTIFICATIVA E OBJETIVOS: Diminuir o sangramento durante a cirurgia funcional endoscópica dos seios paranasais é essencial. Nosso objetivo primário foi investigar os efeitos de dexmedetomidina e sulfato de magnésio, usados para o controle da hipotensão, sobre a visibilidade do sítio cirúrgico. MÉTODOS: Foram incluídos no estudo 60 pacientes entre 18 e 65 anos. No grupo sulfato de magnésio (Grupo M), receberam 40 mg de sulfato de magnésio em 100 mL kg-1 de solução salina durante 10 minutos como dose de carga intravenosa 10 minutos antes da indução e infusão subsequente de 10-15 µg kg-1 h-1 durante a cirurgia. No grupo dexmedetomidina (Grupo D), receberam 1 µg kg-1 de dexmedetomidina em 100 mL de solução salina durante 10 minutos como dose de carga 10 minutos antes da cirurgia e 0,5-1 µg kg-1 h-1 de dexmedetomidina durante a cirurgia. Hipotensão controlada foi definida como pressão arterial média de 60-70 mmHg. RESULTADOS: O volume de sangramento diminuiu significativamente no grupo D (p = 0,002). Os valores da pressão arterial média foram significativamente menores no Grupo D, em comparação com o Grupo M, exceto no estágio inicial, pós-indução e cinco minutos pós-intubação (p < 0,05). No Grupo D, o número de pacientes que necessitou de nitroglicerina foi significativamente menor (p = 0,01) e o grau de satisfação do cirurgião foi significativamente maior (p = 0,001). O tempo de recuperação para atingir o escore de Aldrete ≥ 9 foi significativamente menor no grupo D (p = 0,001). Não houve diferença entre os dois grupos em relação aos escores da escala numérica de classificação verbal na sala de recuperação. CONCLUSÕES: Dexmedetomidina pode proporcionar um controle mais eficaz da hipotensão e contribuir, assim, para uma melhor visibilidade do sítio cirúrgico. .

JUSTIFICACIÓN Y OBJETIVOS: Disminuir el sangrado durante la cirugía funcional endoscópica de los senos paranasales es esencial. Nuestro objetivo primario fue investigar los efectos de la dexmedetomidina y del sulfato de magnesio, usados para el control de la hipotensión, sobre la visibilidad del campo quirúrgico. MÉTODOS: Fueron incluidos en el estudio 60 pacientes entre 18 y 65 años. En el grupo sulfato de magnesio (grupo M), recibieron 40 mg de sulfato de magnesio en 100 mL/kg-1 de solución salina durante 10 min como dosis de carga intravenosa 10 min antes de la inducción e infusión subsecuente de 10-15 µg/kg-1/h-1 durante la cirugía. En el grupo dexmedetomidina (grupo D), recibieron 1 µg/kg-1 de dexmedetomidina en 100 mL de solución salina durante 10 min como dosis de carga 10 min antes de la cirugía y 0,5-1 µg/kg-1/h-1 de dexmedetomidina durante la cirugía. La hipotensión controlada se definió como presión arterial media de 60-70 mmHg. RESULTADOS: El volumen de sangrado disminuyó significativamente en el grupo D (p = 0,002). Los valores de la presión arterial media fueron significativamente menores en el grupo D en comparación con el grupo M, excepto en el estadio inicial, postinducción y 5 min postintubación (p < 0,05). En el grupo D, el número de pacientes que necesitó nitroglicerina fue significativamente menor (p = 0,01) y el grado de satisfacción del cirujano fue significativamente mayor (p = 0,001). El tiempo de recuperación para alcanzar la puntuación de Aldrete ≥ 9 fue significativamente menor en el grupo D (p = 0,001). No hubo diferencia entre los 2 grupos con relación a las puntuaciones de la escala numérica de clasificación verbal en la sala de recuperación. CONCLUSIONES: La dexmedetomidina puede proporcionar un control más eficaz de la hipotensión y contribuir así a una mejor visibilidad del campo quirúrgico. .

Protection of Electro-acupuncture for Gastric Mucosa of Patients Undergoing Endoscopic Sinus Surgery / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To evaluate the effect of electro-acupuncture (EA) on gastric mucosal oxygenation and systemic inflammatory response in patients undergoing endoscopic sinus surgery with controlled hypotension (CH), and to explore its protective effect on gastric mucosa.</p><p><b>METHODS</b>Fifty-four patients, 18-65 years old, grade I-II of American Society of Anesthesiology (ASA), who were scheduled for endoscopic sinus surgery were randomly assigned to two groups, group A (general anesthesia group) and group B (general anesthesia combined EA anesthesia group), 27 in each group. Conrolled hypotension was executed during operation, and mean arterial pressure (MAP) was maintained at 55-65 mmHg. After tracheal intubation gastric tesiometer catheter was indwelled through nasal cavity or oral cavity. After successful indwelling, it was connected with gastric mucosa monitoring mode of multifunctional parameters monitor. Patients' MAP and heart rate (HR), pHi, partial pressure of carbon dioxide (PgCO2), arterial partial pressure of carbon dioxide (Pg-aCO2) and endtidal pressure of carbon dioxide (Pg-etCO2) were measured and recorded at T, (immediately before induced hypotension), T, (20 min following induced hypotension to target MAP), T2 (40 min following induced hypotension to target MAP), T3 (20 min after ending induced hypotension), and T4(40 min after ending induced hypotension). Blood samples were intravenously collected, TNF-alpha, IL-1, and IL-6 were detected by ELISA 24 h before operation, during operation (T3), and 24 h after operation.</p><p><b>RESULTS</b>After hypotension was induced, Pg-CO2, Pg-aCO2 and Pg-etCO2 increased significantly (P < 0.01, P < 0.05), while pHi decreased significantly (P < 0.01) in both groups at T1-T4 than those at T0. During T1-T4, PgCO2, Pg-aCO2, and Pg-etCO2 were higher (P < 0.01, P < 0.05), while pHi was lower in group A than in group B (P < 0.01). Furthermore, TNF-alpha, IL-1, and IL-6 increased significantly in both groups during operation and 24 h after operation, when compared with those 24 h before operation (P < 0.01, P < 0.05). TNF-alpha and IL-1 in group A were higher than those in group B (P < 0.05) during operation and 24 h after operation, but with no significant difference in the plasma concentration of IL-6 (P > 0.05).</p><p><b>CONCLUSION</b>EA exerted obvious protective effect of gastric mucosal injury in endoscopic sinus surgery with controlled hypotension, which might be achieved by increasing gastric mucosal blood flow, maintaining oxygen supply and demand, inhibiting inflammatory response, and alleviating injury of gastric mucosal barrier.</p>

Gastric dynamics analysis of TEAS combined SNP induced general anesthesia when controlled hypotension dropped to 60% of the MAP baseline / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of gastric dynamics by transcutaneous electrical acupoint stimulation (TEAS) combined general anesthesia when controlled hypotension dropped to 60% of the mean arterial prenssure (MAP) baseline, and to provide experimental evidence for organ protection in clinical controlled hypotension.</p><p><b>METHODS</b>Eighteen male beagles were randomly divided into three groups, the general anesthesia group (blank), the general anesthesia induced controlled hypotension group (control), and the general anesthesia combined TEAS induced controlled hypotension group (experiment), 6 in each group. Controlled hypotension was performed in the latter two groups with isoflurane inhalation and intravenous injection of sodium nitroprusside (SNP). The mean arterial pressure (MAP) was lowered to 60% of the MAP baseline and kept for 60 min. Controlled hypotension was not performed in Beagles of the control group. For Beagles in the experiment group, TEAS [2/100 Hz, (4 ± 1) mA] was applied to bilateral Hegu (LI4), Quchi (LI11), Zusanli (ST36), and Sanyinjiao (SP6) from stable physiological conditions to the end of maintaining stages. Changes of EGG frequencies and EGG amplitudes were monitored. Serum levels of gastrin (GAS) and motilin (MTL) were also detected at corresponding time points during and after experiment.</p><p><b>RESULTS</b>As for the pressure control effect of TEAS combined general anesthesia in the controlled hypotension, during the process of controlled hypotension (T1-T4), MAP levels of two controlled pressure groups remained relatively stable, and were kept at 60% of the MAP baseline. When the blood pressure dropped to the target low MAP and maintained at 60 min (T1-T4), EGG amplitudes of Beagles in all the three groups showed decreasing tendency. But it was more obviously lower than its basic level in the control group (P <0.05), while it was not obviously decreased in the experiment group (P < 0.05). EGG frequencies of Beagles in all the three groups showed no obvious change during this stage. By the end of the MAP rising stage (T8), the EGG amplitude of the experimental group was significantly higher than that of the control group and the blank group (P < 0.05), while it didn' t show any obvious increase in the control group. During this period, EGG frequencies of the two controlled hypotension groups decreased more than those of the blank group. Two h after rising blood pressure (at T9), EGG amplitudes and frequencies in the two controlled hypotension groups basically restored to their respective baselines and levels of the blank group at T9. At 2 h (T9) after controlled hypotension, serum levels of GAS and MTL were lower than those of basic levels in the two controlled hypotension groups (P <0.05). However, serum levels of GAS and MTL had an increasing trend in the two controlled hypotension groups at 24-72 h (T10-T12). Besides, the increasing speed and amplitude was better in experiment group than in the control group at T10-T12. However, there was no statistical difference between the two groups (P > 0.05). At 72 h (T12) serum levels of GAS and MTL had basically restored to their basic levels in the two controlled hypotension groups and that of the blank control group.</p><p><b>CONCLUSION</b>EGG amplitudes could be effectively improved in TEAS combined general anesthesia for controlled hypotension at 60% of the MAP baseline, the recovery of the serum GAS level accelerated, gastric power improved and stomach protected.</p>

Changes of endoplasmic reticulum stress- and apoptosis-related factors in rat cerebral cortex following controlled hypotension / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes of endoplasmic reticulum stress (ERS)- and apoptosis-related factors in rat cerebral cortex following controlled hypotension.</p><p><b>METHODS</b>Twenty-four healthy male SD rats were randomly divided into 4 equal groups, including a sham hypotension group (group A) and 3 hypotension groups with the mean arterial pressure maintained for 60 min at 70 mmHg (group B), 50 mmHg (group) and 30 mmHg (group D) with sodium nitroprusside and esmolol. All the rats received an equal volume of fluid infusion. Twelve hours after controlled hypotension, the rats were sacrificed to examine the protein expressions of Bax, Bcl-2, glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP) and caspase-12 in the cortex with Western blotting. GRP78 mRNA expression was measured by RT-PCR, and the cell apoptosis was evaluated by TUNEL staining.</p><p><b>RESULTS</b>Compared with those in group A, GRP78 mRNA and protein expressions of GRP78, CHOP, caspase-12 related with ERS increased significantly in groups C and D (P<0.05), especially in group D (P<0.05), but not in group B (P>0.05). Apoptotic cells and Bax expression increased and Bcl-2 expression decreased significantly in groups C and D (P<0.05), but not in group B (P>0.05); such changes were more prominent in group D than in group C (P<0.05).</p><p><b>CONCLUSION</b>Mild controlled hypotension (70 mmHg) does not induce neuronal injury in rat cerebral cortex, but severe hypertension (lower than 50 mmHg) can cause neuronal ERS and apoptosis.</p>

Hipertermia por intermação em cão: relato de caso / Hyperthermia due to heat stroke in dogs: case report

O objetivo deste trabalho é relatar um caso de hipertermia por intermação em um cão da raça São Bernardo, destacando os procedimentos emergenciais realizados para o controle desta enfermidade.

Efeitos do óxido nitroso em hipotensão controlada durante anestesia com baixo fluxo / The effects of nitrous oxide on controlled hypotension during low flow anesthesia / Efectos del óxido nitroso en la hipotensión controlada durante la anestesia con bajo flujo

JUSTIFICATIVA E OBJETIVOS: Investigamos o efeito do óxido nitroso (N2O) em hipotensão controlada durante anestesia com baixo fluxo (isoflurano-dexmedetomidina) em termos de hemodinâmica, consumo de anestésico e custos. MÉTODOS: Quarenta pacientes foram randomicamente alocados em dois grupos. Infusão de dexmedetomidina (0,1 µg.kg-1.min-1) foi mantida por 10 minutos. Subsequentemente, essa infusão foi mantida até os últimos 30 minutos de operação a uma dose de 0,7 µg.kg-1.hora-1. Tiopental (4-6 mg.kg-1) e brometo de vecurônio (0,08 0,12 mg.kg-1) foram administrados na indução de ambos os grupos. Isoflurano (2%) foi administrado para manutenção da anestesia. O Grupo N recebeu uma mistura de 50% de O2-N2O e o Grupo A recebeu uma mistura de 50% de O2-ar como gás de transporte. Anestesia com baixo fluxo (1 L.min-1) foi iniciada após um período de 10 minutos de alto fluxo inicial (4,4 L.min-1). Os valores de pressão arterial, frequência cardíaca, saturação periférica de O2, isoflurano inspiratório e expiratório, O2 inspiratório e expiratório, N2O inspiratório e expiratório, CO2 inspiratório, concentração de CO2 após expiração e concentração alveolar mínima foram registrados. Além disso, as taxas de consumo total de fentanil, dexmedetomidina e isoflurano, bem como de hemorragia, foram determinadas. RESULTADOS: A frequência cardíaca diminuiu em ambos os grupos após a carga de dexmedetomidina. Após a intubação, os valores do Grupo A foram maiores nos minutos um, três, cinco, 10 e 15. Após a intubação, os valores de hipotensão desejados foram alcançados em 5 minutos no Grupo N e em 20 minutos no grupo A. Os valores da CAM foram mais altos no Grupo N nos minutos um, três, cinco, 10 e 15 (p < 0,05). Os valores da FiO2 foram mais altos entre 5 e 60 minutos no Grupo A, enquanto foram mais altos no Grupo N aos 90 minutos (p < 0,05). Os valores de Fi Iso (isoflurano inspiratório) foram menores no Grupo N nos minutos 15 e 30 (p < 0,05). CONCLUSÃO: O uso de dexmedetomidina em vez de óxido nitroso em anestesia com isoflurano pela técnica de baixo fluxo atingiu os níveis desejados de pressão arterial média (PAM), profundidade suficiente da anestesia, estabilidade hemodinâmica e parâmetros de inspiração seguros. A infusão de dexmedetomidina com oxigênio-ar medicinal como gás de transporte é uma técnica anestésica opcional.

BACKGROUND AND OBJECTIVES: We investigated the effect of Nitrous Oxide (N2O) on controlled hypotension in low-flow isoflurane-dexmedetomidine anesthesia in terms of hemodynamics, anesthetic consumption, and costs. METHODS: We allocated forty patients randomly into two equal groups. We then maintained dexmedetomidine infusion (0.1 µg.kg-1.min-1) for 10 minutes. Next, we continued it until the last 30 minutes of the operation at a dose of 0.7 µg.kg-1.hour-1. We administered thiopental (4-6 mg. kg-1) and 0.08-0.12 mg.kg-1 vecuronium bromide at induction for both groups. We used isoflurane (2%) for anesthesia maintenance. Group N received a 50% O2-N2O mixture and Group A received 50% O2-air mixture as carrier gas. We started low-flow anesthesia (1 L.min-1) after a 10-minute period of initial high flow (4.4 L.min-1). We recorded values for blood pressure, heart rate, peripheral O2 saturation, inspiratory isoflurane, expiratory isoflurane, inspiratory O2, expiratory O2, inspiratory N2O, expiratory N2O, inspiratory CO2, CO2 concentration after expiration, Minimum Alveolar Concentration. In addition, we determined the total consumption rate of fentanyl, dexmedetomidine and isoflurane as well as bleeding. RESULTS: In each group the heart rate decreased after dexmedetomidine loading. After intubation, values were higher for Group A at one, three, five, 10, and 15 minutes. After intubation, the patients reached desired hypotension values at minute five for Group N and at minute 20 for group A. MAC values were higher for Group N at minute one, three, five, 10, and 15 (p < 0.05). FiO2 values were high between minute five and 60 for Group A, while at minute 90 Group N values were higher (p < 0.05). Fi Iso (inspiratuvar isofluran) values were lower in Group N at minute 15 and 30 (p < 0.05). CONCLUSION: By using dexmedetomidine instead of nitrous oxide in low flow isoflurane anesthesia, we attained desired MAP levels, sufficient anesthesia depth, hemodynamic stability and safe inspiration parameters. Dexmedetomidine infusion with medical air-oxygen as a carrier gas represents an alternative anesthetic technique.

JUSTIFICATIVA Y OBJETIVOS: Investigamos el efecto del óxido nitroso (N2O) en hipotensión controlada durante anestesia con bajo flujo (isoflurano-dexmedetomidina) en términos de hemodinámica, consumo de anestésico y costes. MÉTODOS: Cuarenta pacientes fueron aleatoriamente divididos en dos grupos iguales. La infusión de dexmedetomidina (0,1 µg.kg-1.min-1) se mantuvo entonces por 10 minutos. En secuencia, esa infusión se mantuvo hasta los últimos 30 minutos de operación en una dosis de 0,7 µg.kg-1.hour-1. El tiopental (4-6 mg.kg-1) y el bromuro de vecuronio (0,08 0,12 mg.kg-1) fueron administrados en la inducción de ambos grupos. El Isofluorano (2%) fue administrado para el mantenimiento de la anestesia. El Grupo N recibió una mezcla de un 50% de O2-N2O y el Grupo A recibió una mezcla de un 50% de O2-ar como gas de transporte. La anestesia con bajo flujo (1 L.min-1) fue iniciada después de un período de 10 minutos de alto flujo inicial (4,4 L.min-1). Se registraron los valores de la presión arterial, frecuencia cardíaca, saturación periférica de O2, isoflurano inspiratorio, isoflurano espiratorio, O2 inspiratorio, O2 espiratorio, N2O inspiratorio, N2O espiratorio, CO2 inspiratorio, concentración de CO2 después de la espiración y concentración alveolar mínima. Además, de determinaron las tasas de consumo total de fentanil, dexmedetomidina e isoflurano, como también la de hemorragia. RESULTADOS: La frecuencia cardíaca disminuyó en ambos grupos después de la carga de dexmedetomidina. Después de la intubación, los valores del Grupo A fueron mayores en los minutos 1, 3, 5, 10 y 15. Después de la intubación, los valores de hipotensión deseados se alcanzaron en 5 minutos en el Grupo N y en 20 minutos en el grupo A. Los valores de la CAM fueron más altos en el Grupo N en los minutos 1, 3, 5, 10 y 15 (p < 0,05). Los valores de la FiO2 fueron más altos entre 5 y 60 minutos en el Grupo A, mientras que fueron más altos en el Grupo N a los 90 minutos (p < 0,05). Los valores de Fi Iso (isoflurano espiratorio) fueron menores en el Grupo N en los minutos 15 y 30 (p < 0,05). CONCLUSIONES: El uso de la dexmedetomidina en vez del óxido nitroso en la anestesia con el isoflurano por la técnica de bajo flujo, alcanzó los niveles deseados de presión arterial promedio (PAP), profundidad suficiente de la anestesia, estabilidad hemodinámica y parámetros de inspiración seguros. La infusión de dexmedetomidina con oxígeno / aire medicinal como gas de transporte es una técnica anestésica opcional.

Etilefrina para la corrección de la hipotensión arterial materna durante cesáreas bajo bloque subaracnoideo y riesgo de hipoglucemia neonatal, Hospital Guillermo Almenara, Enero a Marzo del 2013 / Etilefrine for correction of maternal hypotension during caesarean section with subarachnoid block and risk of neonatal hypoglycemia, Hospital Guillermo Almenara, January to March 2013

Introducción: El presente estudio analizó casos de gestantes sometidas a bloqueo subaracnoideo (BSA) para cesárea y que necesitaron el uso de etilefrina para la corrección de la hipotensión arterial materna. Métodos: Se incluyeron a las gestantes sometidas a cesárea bajo BSA en el periodo enero a marzo del 2013, en el Hospital Almenara de Lima Perú, se excluyeron a los neonatos inmaduros, con RCIU, hijos de madres diabéticas, con enfermedad hemolítica RH, con asfixia, sepsis, policitemia y/o hipotermia neonatal, y se compararon las glicemias de la primera y segunda hora de vida de los neonatos, agrupados según el factor de exposición (administración de etilefrina a sus madres durante la cesárea), mediante la prueba estadística del t de student y en tablas de contingencia se calculó el riesgo relativo para la exposición. Resultados: La edad promedio para ambos grupos de pacientes es 30 años, la talla promedio del grupo expuesto es 1.55m y del grupo no expuesto es 1.57m, la mediana para el peso del grupo expuesto es 69 Kg y del grupo no expuesto es 72 Kg, la mediana para la edad gestacional del grupo expuesto es 38 semanas y del grupo no expuesto es 39 semanas. El promedio del peso de los neonatos del grupo expuesto es 3318 g y del grupo no expuesto es 3444 g. El promedio de la glicemia en la primera hora de vida de los neonatos del grupo expuesto es 57 mg/dl y del grupo no expuesto es 56 mg/dl; el promedio de la glicemia en la segunda hora de vida de los neonatos del grupo expuesto es 63 mg/dl y del grupo no expuesto es 65 mg/dl. La prueba de t de student para el promedio de las glicemias a la primera y segunda hora de vida de los neonatos, no mostró diferencias significativas entre ambos grupos, pero en las tablas de contingencia se calculó un riesgo relativo para el factor de exposición de 2.68 (IC 95 por ciento 0.68 a 10.47), es decir la exposición es un factor de riesgo pero sin asociación causal. Conclusiones: Existe mayor riesgo de hipoglicemia neonatal...

Background: The present study analyzed cases of pregnant women undergoing subarachnoid block (BSA) for cesarean section and requiring the use of ethylephrine to correct maternal hypotension. Methods: We included pregnant women undergoing cesarean section under BSA in the period January to March 2013, at the Hospital Almenara in Lima Peru, were excluded immature newborns with IUGR, newborns of diabetic mothers with RH hemolytic disease, with asphyxia, sepsis, polycythemia and/or neonatal hypothermia and compared the glucose levels of the first and second hour of life for newborns, grouped according to the exposure factor (ethylephrine administration to their mothers during caesarean section), using the statistical test Student's t contingency tables and calculated the relative risk for exposure. Results: The average age for both groups of patients is 30 years, the average size of the exposed group is 1.55m the unexposed group is 1.57m, the median weight is 69 kg exposed group and the unexposed group is 72 kg, the median gestational age of 38 weeks is exposed group and the unexposed group is 39 weeks. The average weight of the newborns in the exposed group is 3318 g and the unexposed group is 3444 g. The mean blood glucose in the first hour of life of newborns exposed group is 57 mg/dI and the unexposed group is 56 mg/dI, the mean blood glucose during the second hour of life of newborns in the exposed group is 63 mg/dI. and the unexposed group is 65 mg/dI. The Student t test for average blood glucose for the first and second hour of life of newborns showed no significant differences between both groups, but in the contingency tables was calculated relative risk for the exposure factor of 2.68 (95 per cent Cl 0.68 to 10.47), the exposure is a risk factor but no causal association. Conclusions: There is increased risk of neonatal hypoglycemia associated with the use of ethylephrine to correct maternal hypotension during caesarean section under BSA.

The effect of dexmedetomidine on post-operative blood pressure after controlled hypotension in endoscopic sinus surgery / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To observe the variance of blood pressure (BP) after controlled hypotension in endoscopic sinus surgery with dexmedetomidine.@*METHOD@#Sixty patients undergoing elective endoscopic sinus surgery were randomly assigned to receive dexmedetomidine (Group D) or physiological saline (Group S). For the two groups, after the same induction of anesthesia procedure, Group D were injected with dexmedetomidine with 0.8 microg/kg of priming dose in 10 min and 0.5 microg/(kg x h) of maintenance dose i. v. drip for 30 min. The Group S were injected with physiological saline in the dose the same as Group D. The measurement of the mean aortic pressure(MAP), heart rate (HR) and the colouration of the Nasal packing material and exudation were taken at the end of the surgery (T1), at the time of extubation (T2), 10 min after extubation (T3), 30 min after extubation (T4), 2 h after extubation (T5), and 4 h after extubation (T6).@*RESULT@#The MAP and HR of Group S at the points T2-T6 were significantly higher compared with those at the point T1 (P 0.05). The MAP and HR of Group S at each time point were higher compared with Group D (P < 0.05). The number of cases with postoperative nasal exudate in Group S was significantly more than in Group D (27:18) (P < 0.05).@*CONCLUSION@#The perioperative dexmedetomidine medication can significantly reduce fluctuations in BP in endoscopic sinus surgery, so that to stable hemodynamics and reduce nasal bleeding.

Inflammatory-modulating mechanism of transcutaneous electrical acupoint stimulation combined with general anesthesia or controlled hypotension on postoperative hippocampal neuroprotection / 中国针灸

<p><b>OBJECTIVE</b>To observe the effects of transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia or controlled hypotension on hippocampal neuronal damage and the inflammatory response in peripheral circulation and central nervous system (CNS) after surgery, and to investigate its brain protection mechanism.</p><p><b>METHODS</b>Eighteen healthy male beagles aged 6 - 8 months were randomly divided into a general anesthesia group (group G), a controlled hypotension group (group C) and a compound anesthesia acupuncture group (group A), 6 cases in each group. Dogs in group G was anesthetized by isoflurane inhalation, and group C was combined with intravenous infusion of sodium nitroprusside based on isoflurane inhalation to induce hypotension, and followed surgery after achieving the target blood pressure, and group A was combined with TEAS at "Quchi" (LI 11), "Hegu" (LI 4) "Zu sanli" (ST 36) and "Sanyinjiao" (SP 6) based on controlled hypotension, and then brain tissue was taken out on the 72 h after mean arterial pressure (MAP) was returned to baseline levels. The concentration of IL-1beta,TNF-alpha in serum at different time points were detected by ELISA. The expression of IL-1beta, TNF-alpha, Bcl-2, Bax and cleaved caspase-3 were measured by immunohistochemistry, and the apoptosis of hippocampus were detected by TUNEL.</p><p><b>RESULTS</b>(1) At different time points, the concentration of TNFalpha showed the trend of increase first and then decrease, while IL-1beta concentration represented a trend of decrease first and then increase in both group C and group A, but there were no significant differences in cytokine expression between the two groups (all P > 0.05). (2) The ratio of positive cells of IL-1beta, TNF-alpha and caspase-3 in CA1 and CA3 of hippocampus in both group C and A were higher than those in group G (all P < 0.01), and cytokines expression in group A were lower than those in group C (all P < 0.01), and caspase-3 in CA1 in group A was lower than that in group C (P < 0.01). The ratio of Bcl-2/Bax in both group C and A were lower than that in group G (all P < 0.01), and that in group A was higher than that in group C (P < 0.01 in CA1, P < 0.05 in CA3). (3) The apoptosis index (AI) of hippocampal neurons in both group C and A was significantly higher than that in group G (P < 0.01), while AI in CA1 in group A was lower than that in group C (P < 0.01).</p><p><b>CONCLUSION</b>The TEAS can regulate the expression of inflammatory factor in hippocampus in animals undergoing general anesthesia or con trolled hypotension surgery, further improving Bcl-2/Bax ratio, inhibiting the expression of caspase-3 and reducing neuron apoptosis in hippocampus so as to play a neuroprotection.</p>

[Comparison of blood loss in femoral shaft surgeries between tranexamic acid and controlled hypotension]

Blood loss reducing approaches improve surgery outcomes through producing an appropriate operation field and reducing transfusion need. In this study two blood loss reducing techniques were compared. In a randomized clinical trial study 60 patients candidate for elective femoral shaft operation were devided in two groups. The first group went under induced hypotensionand the second group received tranexamic acid. Anesthesia technique and surgeon were the same in both groups. Bleeding amountwas measured based on site operation site and reservoir observing, pads counting. Traputic interventions such as crystalloids or colloids and blood transfusion were done as needed. Results were evaluated by Mann-witney U test. Dry field and surgeons satisfaction was good in 23 patinets of the hypotention group [76%] and was moderate in the rest of the group. In the tranexamic group the results were good in 21 patients [70%]. There was no significant difference in reducing blood loss between the groups. Both of the studied techniques can reduce bleeding and improve operation field and surgeon satisfaction, meanwhile there was no significant difference in two approaches