RESUMEN
El objetivo de esta investigación fue estudiar la variación de la Posición Natural de Cabeza (PNC) entre personas con dentición mixta segunda fase y dentición permanente, mediante fotogrametría facial. Para esto se realizó un estudio comparativo observacional analítico. La muestra estuvo conformada por 80 voluntarios divididos en dos grupos de 40 participantes cada uno. Se utilizó fotografías faciales de perfil estandarizadas en PNC. Mediante el software Photoshop® se trazó el plano Intertrágico-Exocanto (t-ex) y se midió el ángulo formado respecto a la horizontal verdadera para determinar la inclinación de la PNC. El valor de este ángulo se obtuvo mediante el software UTHSCSA ImageTool 3.0®. Los datos fueron tabulados en una planilla Excel (Microsoft® Excel® 2016) y analizados estadísticamente en el programa Stata 14 S/E®. Se observaron diferencias estadísticas en la inclinación de la PNC entre los grupos, con valores promedio 26.17° y 33.44° para dentición mixta segunda fase y permanente respectivamente, con una diferencia promedio de 7.27°. Se concluyó que la PNC de personas con dentición permanente presenta una rotación antihoraria respecto a personas con dentición mixta segunda fase.
This research aimed at studying the variation of the Natural Head Position (NHP) between people with second transitional mixed dentition and permanent dentition, using facial photogrammetry. For this, an analytical observational comparative study was performed. The sample consisted of 80 volunteers divided into two groups of 40 participants each. Using standardized profile facial photographs in NHP and Photoshop® software, the intertragic-exocanthion plane (t- ex) was traced. The angle formed to the true horizontal was measured to determine the inclination of the NHP using the UTHSCSA ImageTool 3.0® software. The data were tabulated in an Excel Spreadsheet (Microsoft® Excel® 2016) and analyzed with Stata 14 S/E® software. Statistical differences in the inclination of the NHP between groups were observed, with average values of 26.17° for second transitional mixed dentition and 33.44° for permanent dentition, with an average difference of 7.27°. It was concluded that the NHP of people with permanent dentition shows an anti-clockwise rotation in relation to people with second transitional mixed dentition.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Programas Informáticos , Fotogrametría , Inclinación de Cabeza , Dentición , Estudio ComparativoRESUMEN
Objetivo: estudiar y comparar la inclinación de la cabeza entre niños con dentición primaria completa y dentición mixta primera fase. Materiales y métodos: el estudio incluyó a 80 voluntarios entre 4 y 9 años, a quienes se les tomó una fotografía facial de perfil derecho estandarizada, en Posición Natural de Cabeza. Éstas fueron analizadas mediante software de edición de imágenes para determinar la inclinación de la cabeza de cada voluntario. Para ello, se definió un plano (plano t-ex) formado por el punto Intertrágico (t) y Exocanto (ex) y se comparó respecto a la horizontal verdadera. Los datos obtenidos fueron tabulados, clasificados en dos grupos según el tipo de dentición y analizados estadísticamente. Resultados: el promedio de inclinación del plano t-ex fue de 22,7º en el grupo de niños con dentición primaria completa y de 25,8º en el grupo de niños con dentición mixta primera fase. La diferencia entre ambos grupos fue de 3,1º, con significancia estadística (p = 0,006). Conclusión: la inclinación de la cabeza de los niños con dentición mixta primera fase es mayor en sentido antihorario, respecto a la de los niños con dentición primaria completa.
Objective: to study and compare head tilt among children with complete primary dentition and first transitional period of the mixed dentition stage. Materials and methods: the study included 80 volunteers between 4 and 9 years of age, who were taken a standardized right profile facial photograph in a Natural Head Position. These photographs were analyzed using image editing software to determine the head tilt of each volunteer. For this, a plane (plane t-ex) formed by the Intertragic point (t) and Exocanth (ex) was defined and compared with respect to the true horizontal. The data obtained were tabulated, classified into two groups according to the type of dentition and statistically analyzed. Results: the average t-ex plane inclination was 22.7º in the group of children with complete primary dentition and 25.8º in the group of children with first transitional period of the mixed dentition stage. The difference between both groups was 3.1º, with statistical significance (p = 0.006). Conclusion: the head tilt of children with first transitional period of the mixed dentition stage is greater in an anti-clockwise direction, compared to that of children with complete primary dentition.
Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Inclinación de Cabeza , Dentición , Dentición MixtaRESUMEN
To determine the effect of Trendelenburg position on the diameter or cross-section area of the internal jugular vein (IJV) a systematic review and metanalysis was performed. Studies that evaluated the cross-sectional area (CSA) and anteroposterior (AP) diameter of the right internal jugular vein (RIJV) with ultrasonography in supine and any degree of head-down tilt (Trendelenburg position) were analyzed. A total of 22 articles (613 study subjects) were included. A >5° Trendelenburg position statistically increases RIJV CSA and AP diameter. Further inclination from 10° does not statistically benefit IJV size. This position should be recommended for CVC placement, when patient conditions allow it, and US-guided cannulation is not available.
Asunto(s)
Cateterismo Venoso Central , Inclinación de Cabeza , Venas Yugulares , Humanos , Venas Yugulares/diagnóstico por imagen , Posicionamiento del Paciente , UltrasonografíaRESUMEN
Most guidelines fail to specify patient positioning during central venous catheterization. The objective was to determine the effects of head-down tilt (Trendelenburg position) and head rotation on the internal jugular vein (IJV). A prospective, observational, longitudinal, and descriptive study using healthy adult volunteers, of both sexes, was performed. The change in position and cross-sectional areas (CSA) of the right IJV and common carotid artery (CA) were measured by ultrasonography during Trendelenburg position (TP) (0°, 5°, 10°, and 15°) and contralateral head-rotation (HR) (0°, 45°, and 90°) for a total of 12 positions. The neutral supine position was first, randomizing the other 11 positions, with 5-min rest intervals in between. Vital signs and symptoms were recorded. A total of 54 volunteers were recruited between the ages of 21 and 32, of which 30 were men. Any degree of TP or HR significantly increased the CSA. The largest area obtained was 1.78 cm2 with a TP15HR90 which did not have a statistical difference with TP10HR45 1.59 cm2 . A HR90 tended to displace the IJV medially, overlaying the CA. Any degree of TP or HR will significantly increase CSA or the right IJV. A 5° to 10° TP is recommended when the patient's condition allows it, with a 45° HR, without significantly displacing the IJV anterior to the CCA.
Asunto(s)
Cateterismo Venoso Central , Venas Yugulares , Adulto , Cateterismo Venoso Central/efectos adversos , Femenino , Inclinación de Cabeza , Humanos , Venas Yugulares/diagnóstico por imagen , Masculino , Estudios Prospectivos , Posición Supina , Ultrasonografía , Adulto JovenRESUMEN
PURPOSE: To compare hemodynamic effects of two different modes of ventilation (volume-controlled and pressure-controlled volume guaranteed) in patients undergoing laparoscopic gynecology surgeries with exaggerated Trendelenburg position. METHODS: Thirty patients undergoing laparoscopic gynecology operations were ventilated using either volume-controlled (Group VC) or pressure-controlled volume guaranteed mode (Group PCVG) (n = 15 for both groups). Hemodynamic variables were measured using Pressure Recording Analytical Method by radial artery cannulation in addition to peak and mean airway pressures and expired tidal volume. RESULTS: The only remarkable finding was a more stable cardiac index in Group PCVG, where other hemodynamic parameters were similar. Expired tidal volume increased in Group VC while peak airway pressure was lower in Group PCVG. CONCLUSION: PCV-VG causes less hemodynamic perturbations as measured by Pressure Recording Analytical Method (PRAM) and allows better intraoperative hemodynamic control in exaggerated Trendelenburg position in laparoscopic surgery.
Asunto(s)
Laparoscopía , Mecánica Respiratoria , Inclinación de Cabeza , Hemodinámica , Humanos , Laparoscopía/métodos , Respiración Artificial/métodosRESUMEN
Both robotic surgery and head-down tilt increase intracranial pressure by impairing venous blood outflow. Prostatectomy is commonly performed in elderly patients, who are more likely to develop postoperative cognitive disorders. Therefore, increased intracranial pressure could play an essential role in cognitive decline after surgery. We describe a case of a 69-year-old male who underwent a robotic prostatectomy. Noninvasive Brain4careTM intraoperative monitoring showed normal intracranial compliance during anesthesia induction, but it rapidly decreased after head-down tilt despite normal vital signs, low lung pressure, and adequate anesthesia depth. We conclude that there is a need for intraoperative intracranial compliance monitoring since there are major changes in cerebral compliance during surgery, which could potentially allow early identification and treatment of impaired cerebral complacency.
Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Anciano , Inclinación de Cabeza , Humanos , Presión Intracraneal , Masculino , ProstatectomíaRESUMEN
Delirium is the most common postsurgical neurological complication and has a variable incidence rate. Laparoscopic surgery, when associated with the Trendelenburg position, can cause innumerable physiological changes and increase the risk of neurocognitive changes. The association of general anesthesia with a spinal block allows the use of lower doses of anesthetic agents for anesthesia maintenance and facilitates better control over postoperative pain. Our primary outcome was to assess whether a spinal block influences the incidence of delirium in oncologic patients following laparoscopic surgery in the Trendelenburg position. Our secondary outcome was to analyze whether there were other associated factors. A total of 150 oncologic patients who underwent elective laparoscopic surgeries in the Trendelenburg position were included in this randomized controlled trial. The patients were randomized into 2 groups: the general anesthesia group and the general anesthesia plus spinal block group. Patients were immediately evaluated during the postoperative period and monitored until they were discharged, to rule out the presence of delirium. Delirium occurred in 29 patients in total (22.3%) (general anesthesia group: 30.8%; general anesthesia plus spinal block: 13.8% p = 0.035). Patients who received general anesthesia had a higher risk of delirium than patients who received general anesthesia associated with a spinal block (odds ratio = 3.4; 95% confidence interval: 1.2-9.6; p = 0.020). Spinal block was associated with reduced delirium incidence in oncologic patients who underwent elective laparoscopic surgeries in the Trendelenburg position.
Asunto(s)
Delirio/etiología , Laparoscopía/efectos adversos , Neoplasias/cirugía , Anciano , Anestesia General/efectos adversos , Área Bajo la Curva , Delirio/diagnóstico , Femenino , Inclinación de Cabeza , Hemodinámica , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias/patología , Oportunidad Relativa , Periodo Posoperatorio , Curva ROCRESUMEN
Videolaparoscopic procedures have gained prominence due to their low invasiveness, causing less surgical trauma and better post-surgical recovery. However, the increase in intra-abdominal pressure due to the institution of pneumoperitoneum can alter the patient's homeostasis. Therefore, volume-controlled ventilation, associated with positive end-expiratory pressure (PEEP), improves arterial oxygenation and prevents pulmonary collapse, but it can lead to important hemodynamic changes. The aim of this study was to evaluate, comparatively, the effects of positive end expiratorypressure (PEEP) on hemodynamic variables of pigs submitted to volume-controlled ventilation, during pneumoperitoneum and maintained in head-down tilt and determine which PEEP value promotes greater stability on hemodynamic variables. Twenty-four pigs were used, between 55 and 65-day-old, weighing between 15 and 25 kg, randomly divided into 3 distinct groups differentiated by positive end-expiratory pressure: PEEP 0 (volume-controlled ventilation and PEEP of 0 cmH2O), PEEP 5 (volume-controlled ventilation and PEEP of 5 cmH2O) and PEEP 10 (volume-controlled ventilation and PEEP of 10 cmH2O). Volume-controlled ventilation was adjusted to 8 mL/kg of tidal volume and a respiratory rate of 25 movements per min. Anesthesia was maintained with continuous infusion of propofol (0.2 mg/kg/min) and midazolam (1 mg/kg/h). Pneumoperitoneum was performed with carbon dioxide (CO2), keeping the intraabdominal pressure at 15 mmHg and the animals were positioned on a 30° head-down tilt. The evaluations of hemodynamic variables started 30 min after induction of anesthesia (M0), followed by measurements at 15-min intervals (from M15 to M90), completing a total of 7 evaluations. The variables of interest were collected over 90 min and submitted to analysis of variance followed by Tukey's post-hoc test, with P < 0.05. The PEEP 10 group had higher values of CVP and mCPP, while the PEEP 5 group, mPAP and PVR were higher. The PEEP 0 group, on the other hand, had higher means of CI. Regarding the moments, there were differences in HR, SAP, DAP, MAP, CO, IC and TPR. According to the literature, important hemodynamic effects due to pneumoperitoneum are reported, which can be caused by the pressure used in abdominal insufflation, CO2 accumulation, duration of the surgical procedure, hydration status and patient positioning. Mechanical ventilation associated with PEEP can also cause an increase in intrathoracic pressure and, therefore, reduce cardiac output. Cardiovascular changes are proportional to the PEEP used. Central venous pressure (PVC) measure the patient's preload, and intrathoracic pressure can interfere with this parameter. The peak pressure values in the PEEP 10 group were higher than the other groups, demonstrating that the increase in intrathoracic pressure results in higher PVC values. Regarding PAPm and PCPm, these variables can be influenced according to the PEEP values and the patient's position. In relation to CI, the increase in PEEP may reflect on intrathoracic pressure, resulting in greater compression of the heart, with a consequent reduction in cardiac output and cardiac index. Therefore, it is concluded that the PEEP effects of 0 cmH2O and 5 cmH2O on hemodynamics are discrete, under the proposed conditions.(AU)
Asunto(s)
Animales , Neumoperitoneo , Respiración Artificial , Volumen de Ventilación Pulmonar , Laparoscopía/veterinaria , Inclinación de Cabeza/efectos adversos , PorcinosRESUMEN
Abstract Background: The present study investigated the association between Postoperative Cognitive Dysfunction (POCD) and increased serum S100B level after Robotic-Assisted Laparoscopic Radical Prostatectomy (RALRP). Methods: The study included 82 consecutive patients who underwent RALRP. Serum S100B levels were determined preoperatively, after anesthesia induction, and at 30 minutes and 24 hours postoperatively. Cognitive function was assessed using neuropsychological testing preoperatively, and at 7 days and 3 months postoperatively. Results: Twenty four patients (29%) exhibited POCD 7 days after surgery, and 9 (11%) at 3 months after surgery. Serum S100B levels were significantly increased at postoperative 30 minutes and 24 hours in patients displaying POCD at postoperative 7 days (p = 0.0001 for both) and 3 months (p = 0.001 for both) compared to patients without POCD. Duration of anesthesia was also significantly longer in patients with POCD at 7 days and 3 months after surgery compared with patients without POCD (p = 0.012, p = 0.001, respectively), as was duration of Trendelenburg (p = 0.025, p = 0.002, respectively). Composite Z score in tests performed on day 7 were significantly correlated with duration of Trendelenburg and duration of anesthesia (p = 0.0001 for both). Conclusions: S100B increases after RALRP and this increase is associated with POCD development. Duration of Trendelenburg position and anesthesia contribute to the development of POCD. Trial Registry Number: Clinicaltrials.gov (N° NCT03018522).
Resumo Introdução: O presente estudo investigou a associação entre Disfunção Cognitiva Pós-Operatória (DCPO) e aumento do nível sérico de S100B após Prostatectomia Radical Laparoscópica Assistida por Robô (PRLAR). Métodos: O estudo incluiu 82 pacientes consecutivos submetidos à PRLAR. Os níveis séricos de S100B foram determinados: no pré-operatório, após indução anestésica, e aos 30 minutos e 24 horas do pós-operatório. A função cognitiva foi avaliada com testes neuropsicológicos no pré-operatório, no 7° dia pós-operatório (7 DPO) e aos 3 meses após a cirurgia (3 MPO). Resultados: Observamos 24 pacientes (29%) com DCPO no 7 DPO e 9 pacientes com DCPO (11%) após 3 meses da cirurgia. Quando comparados com os pacientes sem DCPO, os níveis séricos de S100B estavam significantemente aumentados aos 30 minutos e às 24 horas do pós-operatório nos pacientes que apresentaram DCPO no 7 DPO (p= 0,0001 para os dois momentos) e 3 meses após a cirurgia (p= 0,001 para os dois momentos) A duração anestésica também foi significantemente maior em pacientes com DCPO no 7 DPO e 3 MPO em comparação com pacientes sem DCPO (p= 0,012, p= 0,001, respectivamente), assim como a duração da posição de Trendelenburg (p= 0,025, p= 0,002, respectivamente). O escore Z composto nos testes realizados no 7 DPO foi significantemente correlacionado com a duração da posição de Trendelenburg e a duração da anestesia (p= 0,0001 para ambos). Conclusão: S100B aumenta após PRLAR e o aumento está associado ao desenvolvimento de DCPO. A duração anestésica e o tempo decorrido em posição de Trendelenburg contribuem para o desenvolvimento de DCPO. Número de registro do estudo: Clinicaltrials.gov (n° NCT03018522)
Asunto(s)
Humanos , Masculino , Anciano , Complicaciones Posoperatorias/sangre , Prostatectomía/efectos adversos , Disfunción Cognitiva/sangre , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Procedimientos Quirúrgicos Robotizados/efectos adversos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Prostatectomía/métodos , Factores de Tiempo , Biomarcadores/sangre , Estudios de Casos y Controles , Estudios Prospectivos , Sensibilidad y Especificidad , Inclinación de Cabeza/efectos adversos , Área Bajo la Curva , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Tempo Operativo , Procedimientos Quirúrgicos Robotizados/métodos , Anestesia General/efectos adversos , Anestesia General/estadística & datos numéricos , Persona de Mediana Edad , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: The present study investigated the association between Postoperative Cognitive Dysfunction (POCD) and increased serum S100B level after Robotic-Assisted Laparoscopic Radical Prostatectomy (RALRP). METHODS: The study included 82 consecutive patients who underwent RALRP. Serum S100B levels were determined preoperatively, after anesthesia induction, and at 30 minutes and 24 hours postoperatively. Cognitive function was assessed using neuropsychological testing preoperatively and at 7 days and 3 months postoperatively. RESULTS: Twenty-four patients (29%) exhibited POCD 7 days after surgery, and 9 (11%) at 3 months after surgery. Serum S100B levels were significantly increased at postoperative 30minutes and 24 hours in patients displaying POCD at postoperative 7 days (p = 0.0001 for both) and 3 months (p = 0.001 for both) compared to patients without POCD. Duration of anesthesia was also significantly longer in patients with POCD at 7 days and 3 months after surgery compared with patients without POCD (p = 0.012, p = 0.001, respectively), as was duration of Trendelenburg (p = 0.025, p = 0.002, respectively). Composite Z score in tests performed on day 7 were significantly correlated with duration of Trendelenburg and duration of anesthesia (p = 0.0001 for both). CONCLUSIONS: S100B increases after RALRP and this increase is associated with POCD development. Duration of Trendelenburg position and anesthesia contribute to the development of POCD. TRIAL REGISTRY NUMBER: Clinicaltrials.gov (N° NCT03018522).
Asunto(s)
Disfunción Cognitiva/sangre , Complicaciones Posoperatorias/sangre , Prostatectomía/efectos adversos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Anciano , Anestesia General/efectos adversos , Anestesia General/estadística & datos numéricos , Área Bajo la Curva , Biomarcadores/sangre , Estudios de Casos y Controles , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Inclinación de Cabeza/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tempo Operativo , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Prostatectomía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
CONTEXTO CLÍNICO: La enfermedad por el Coronavirus 2019 (COVID19, por su sigla en inglés Coronavirus Disease 2019) es una enfermedad respiratoria de humanos producida por un nuevo coronavirus identificado con la sigla SARS-CoV-2. TECNOLOGÍA: La ventilación en decúbito prono o ventilación en prono se refiere a la ventilación mecánica brindada a los pacientes que se encuentran en posición prono ("boca abajo"). El posicionamiento de estos pacientes en prono requiere de la coordinación de entre 5 y 6 integrantes de los cuales uno debe ser un terapista respiratorio (kinesiólogo respiratorio) el cual debe asegurar la estabilidad de tubo endotraqueal y un medico clínico experimentado que pueda re intubar al paciente de ser necesario. Si bien esta técnica no requiere de monitoreo adicional, se debe evaluar con mayor frecuencia el manejo de las secreciones y la necesidad de aspiraciones endotraqueal ya que puede aumenta la cantidad de secreciones. OBJETIVO: El objetivo del presente informe es evaluar la evidencia disponible acerca de la eficacia y seguridad de la ventilación en decúbito prono en el tratamiento de la infección por COVID-19. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas, en buscadores genéricos de internet, y financiadores de salud. Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias (ETS), evaluaciones económicas y guías de práctica clínica (GPC) y recomendaciones de diferentes sistemas de salud. CONCLUSIONES: Evidencia de muy baja calidad proveniente de series de casos y un estudio observacional no permite determinar al eficacia y seguridad del posicionamiento en prono en pacientes con COVID-19 y insuficiencia respiratoria aguda con o sin ventilación mecánica invasiva. Podría mejorar la oxigenación, pero es menos claro su efecto en mortalidad, tiempo de ventilación mecánica, tiempo de internación o en la tasa de pacientes intubados en el caso de pacientes sin ventilación mecánica. No hay información sobre posibles efectos adversos como obstrucción del tubo endotraqueal y úlceras por presión. Instituciones como el Ministerio de Salud de Argentina, la Organización Mundial de la Salud, o Institutos Nacionales de Salud de Estados Unidos, entre otras, recomiendan considerar el posicionamiento prono en pacientes con síndrome de distrés respiratorio agudo, moderado o severo por COVID-19 en ventilación mecánica. En el caso de posicionamiento en prono en pacientes sin ventilación mecánica invasiva, instituciones como Institutos Nacionales de Salud de Estados Unidos, la Sociedad Argentina de Terapia Intensiva y otras instituciones nacionales e internacionales, no mencionan su uso en pacientes con COVID-19. La Organización Mundial de la Salud considera su uso solo en protocolos de investigación para establecer su seguridad y eficacia e Institutos Nacionales de Salud de Estados Unidos considera esta intervención para mejorar la oxigenación en pacientes con hipoxemia refractaria, con el objetivo de retrasar el inicio de la ventilación mecánica invasiva, o cuando la misma está contraindicada. Al momento de realizar este documento es muy alta la incertidumbre asociada a la eficacia y seguridad del posicionamiento en prono para el tratamiento de la infección por COVID-19, debido a que la evidencia disponible es de muy baja calidad, y esto impide arribar a conclusiones firmes. Es importante tener en cuenta que se encuentran en curso más de 50 estudios por lo que puede ser que la incertidumbre actualmente existente se reduzca en el corto a mediano plazo.
Asunto(s)
Humanos , Respiración Artificial/métodos , Infecciones por Coronavirus/terapia , Inclinación de Cabeza , Evaluación en Salud , Análisis Costo-BeneficioRESUMEN
Introdução: O delirium no pós-operatório é a complicação neurológica pós-cirúrgica mais comum. A cirurgia laparoscópica, quando associada à posição de Trendelenburg (PT), traz inúmeras alterações na fisiologia e pode aumentar o risco para o aparecimento de alterações neurocognitivas. A associação de anestesia geral com bloqueio subaracnóideo permite utilizar uma dose menor de agentes anestésicos para a manutenção da anestesia e proporciona melhor controle da dor pós-operatória. Objetivos: Avaliar se o bloqueio subaracnóideo pode influenciar na incidência de delirium no pós-operatório em pacientes oncológicos após cirurgia laparoscópica em PT. Analisar outros fatores associados. Métodos: Estudo prospectivo randomizado e controlado, realizado com pacientes oncológicos submetidos a cirurgias eletivas laparoscópicas em PT. Alocamos 150 pacientes em 2 grupos: G1 - anestesia geral; G2 - anestesia geral associada ao bloqueio subaracnóideo com 15 mg de bupivacaína. Ambos os grupos receberam 50 mcg de morfina intratecal. Os pacientes foram avaliados no pós-operatório imediato até a alta hospitalar para descartar delirium no pós-operatório. Resultados: Foram avaliados 130 pacientes e a incidência de delirium no pós-operatório foi 29 (22,3%), G1 (30,8%) e G2 (13,8%). Os pacientes que receberam apenas anestesia geral apresentaram maior risco de delirium no pós-operatório do que os pacientes que receberam anestesia geral associada ao bloqueio subaracnóideo (OR 3,4 IC 1,2-9,6 p = 0,020). Os pacientes com maior risco foram aqueles com ausência de ensino superior (OR 6,2 IC 1,8-21,5 p = 0,003), idade> 65 anos (OR 3,3 IC 1,2-9,2 p = 0,017) e maior pressão de pneumoperitônio (OR 1,7 IC 1,1-2,5 p = 0,008). Conclusões: O bloqueio subaracnóideo foi associado à redução da incidência de delirium no pós-operatório em pacientes oncológicos submetidos a cirurgias eletivas laparoscópicas em PT. Ausência de ensino superior, idade avançada e maior pressão de pneumoperitônio foram outros fatores de risco identificados e associados a um aumento na incidência de delirium no pós-operatório
Background: Postoperative delirium is the most common post-surgical neurological complication. Laparoscopic surgery, when associated with Trendelenburg position, brings innumerable changes in physiology and could increase the risk for the appearance of neurocognitive changes. The association of general anesthesia with spinal anesthesia allows to use a lower dose of anesthetic agents for the maintenance of anesthesia and provides a better control of postoperative pain. Objectives: The primary outcome was to evaluate if spinal block could influence in the incidence of postoperative delirium in oncologic patients after laparoscopic surgery in Trendelenburg position. The secondary outcome was to analyze if there were factors associated. Methods: A randomized controlled trial was realized with oncologic patients underwent to elective laparoscopic surgeries in Trendelenburg position. We allocated 150 patients in 2 groups. G1 - general anesthesia; G2 - general anesthesia associated with a spinal anesthesia with 15 mg of bupivacaine. Both groups received 50 mcg of spinal morphine. Patients were evaluated in immediate postoperative until discharge from hospital to rule out neurocognitive disorders. Results: We evaluated 130 patients and the incidence of postoperative delirium was 29 (22,3%), G1 (30,8%) and G2 (13,8%). Patients who received only general anesthesia had higher risk for postoperative delirium than patients who received general anesthesia associated with spinal block (OR 3,4 CI 1,2-9,6 p=0,020). Patients at a higher risk were those with absence higher education (OR 6,2 CI 1,8-21,5 p=0,003), age > 65 years (OR 3,3 CI 1,2-9,2 p=0,017) and higher pneumoperitoneum pressure (OR 1,7 CI 1,1-2,5 p=0,008). Conclusions: Spinal block was associated with a reduced incidence of postoperative delirium with oncologic patients underwent to elective laparoscopic surgeries in Trendelenburg position. Low educational level, advanced age and higher pneumoperitoneum pressure were other risk factors identified and associated with an increase in the incidence of postoperative delirium
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Espacio Subaracnoideo , Estudios Retrospectivos , Laparoscopía , Inclinación de Cabeza , Delirio , NeoplasiasRESUMEN
BACKGROUND AND OBJECTIVES: The aim of this study was to investigate the efficacy of the pressure-controlled, volume-guaranteed (PCV-VG) and volume-controlled ventilation (VCV) modes for maintaining adequate airway pressures, lung compliance and oxygenation in obese patients undergoing laparoscopic hysterectomy in the Trendelenburg position. METHODS: Patients (104) who underwent laparoscopic gynecologic surgery with a body mass index between 30 and 40kg.m-2 were randomized to receive either VCV or PCV-VG ventilation. The tidal volume was set at 8mL.kg-1, with an inspired oxygen concentration of 0.4 with a Positive End-Expiratory Pressure (PEEP) of 5mmHg. The peak inspiratory pressure, mean inspiratory pressure, plateau pressure, driving pressure, dynamic compliance, respiratory rate, exhaled tidal volume, etCO2, arterial blood gas analysis, heart rate and mean arterial pressure at 5minutes after induction of anesthesia in the and at 5, 30 and 60minutes, respectively, after pneumoperitoneum in the Trendelenburg position were recorded. RESULTS: The PCV-VG group had significantly decreased peak inspiratory pressure, mean inspiratory pressur, plateau pressure, driving pressure and increased dynamic compliance compared to the VCV group. Mean PaO2 levels were significantly higher in the PCV-VG group than in the VCV group at every time point after pneumoperitoneum in the Trendelenburg position. CONCLUSIONS: The PCV-VG mode of ventilation limited the peak inspiratory pressure, decreased the driving pressure and increased the dynamic compliance compared to VCV in obese patients undergoing laparoscopic hysterectomy. PCV-VG may be a preferable modality to prevent barotrauma during laparoscopic surgeries in obese patients.
Asunto(s)
Procedimientos Quirúrgicos Ginecológicos/métodos , Inclinación de Cabeza , Laparoscopía/métodos , Obesidad/complicaciones , Adulto , Femenino , Humanos , Rendimiento Pulmonar/fisiología , Persona de Mediana Edad , Oxígeno/metabolismo , Respiración con Presión Positiva , Estudios Prospectivos , Respiración Artificial/métodos , Volumen de Ventilación Pulmonar/fisiologíaRESUMEN
Abstract Background and objectives: The aim of this study was to investigate the efficacy of the pressure-controlled, volume-guaranteed (PCV-VG) and volume-controlled ventilation (VCV) modes for maintaining adequate airway pressures, lung compliance and oxygenation in obese patients undergoing laparoscopic hysterectomy in the Trendelenburg position. Methods: Patients (104) who underwent laparoscopic gynecologic surgery with a body mass index between 30 and 40 kg.m-2 were randomized to receive either VCV or PCV-VG ventilation. The tidal volume was set at 8 mL.kg-1, with an inspired oxygen concentration of 0.4 with a Positive End-Expiratory Pressure (PEEP) of 5 mmHg. The peak inspiratory pressure, mean inspiratory pressure, plateau pressure, driving pressure, dynamic compliance, respiratory rate, exhaled tidal volume, etCO2, arterial blood gas analysis, heart rate and mean arterial pressure at 5 minutes after induction of anesthesia in the and at 5, 30 and 60 minutes, respectively, after pneumoperitoneum in the Trendelenburg position were recorded. Results: The PCV-VG group had significantly decreased peak inspiratory pressure, mean inspiratory pressur, plateau pressure, driving pressure and increased dynamic compliance compared to the VCV group. Mean PaO2 levels were significantly higher in the PCV-VG group than in the VCV group at every time point after pneumoperitoneum in the Trendelenburg position. Conclusions: The PCV-VG mode of ventilation limited the peak inspiratory pressure, decreased the driving pressure and increased the dynamic compliance compared to VCV in obese patients undergoing laparoscopic hysterectomy. PCV-VG may be a preferable modality to prevent barotrauma during laparoscopic surgeries in obese patients.
Resumo Justificativa e objetivos: O objetivo deste estudo foi investigar a eficácia dos modos de ventilação garantida por volume controlado por pressão (PCV-VG) e ventilação controlada por volume (VCV) para manter pressões adequadas nas vias aéreas, complacência pulmonar e oxigenação em pacientes obesos submetidos à histerectomia laparoscópica na posição de Trendelenburg. Métodos: Cento e quatro pacientes submetidos à cirurgia ginecológica laparoscópica, com índice de massa corporal entre 30 e 40 kg.m-2, foram randomizados para receber ventilação com VCV ou PCV-VG. O volume corrente foi fixado em 8 mL.kg-1, com uma concentração inspirada de oxigênio de 0,4 e pressão positiva expiratória final (PEEP) de 5 mmHg. Registramos os seguintes parâmetros: pressão de pico inspiratório, pressão inspiratória média, pressão de platô, driving pressure, complacência dinâmica, frequência respiratória, volume corrente expirado, etCO2, gasometria arterial, frequência cardíaca e pressão arterial média aos 5, 30 e 60 minutos, respectivamente, após o pneumoperitônio na posição de Trendelenburg. Resultados: O grupo PCV-VG apresentou uma redução significativa da pressão de pico inspiratório, pressão inspiratória média, pressão de platô, driving pressure e aumento da complacência dinâmica comparado ao grupo VCV. Os níveis médios de PaO2 foram significativamente maiores no grupo PCV-VG do que no grupo VCV em todos os momentos após o pneumoperitônio na posição de Trendelenburg. Conclusões: O modo de ventilação PCV-VG limitou a pressão de pico inspiratório, diminuiu a driving pressure e aumentou a complacência dinâmica, comparado ao VCV em pacientes obesas submetidas à histerectomia laparoscópica. O PCV-VG pode ser uma modalidade preferida para prevenir o barotrauma durante cirurgias laparoscópicas em pacientes obesos.
Asunto(s)
Humanos , Femenino , Adulto , Procedimientos Quirúrgicos Ginecológicos/métodos , Laparoscopía/métodos , Inclinación de Cabeza , Obesidad/complicaciones , Oxígeno/metabolismo , Respiración Artificial/métodos , Volumen de Ventilación Pulmonar/fisiología , Rendimiento Pulmonar/fisiología , Estudios Prospectivos , Respiración con Presión Positiva , Persona de Mediana EdadRESUMEN
BACKGROUND: The Trendelenburg position (TP) has been empirically used to increase preload and thus cardiac output (CO). Transthoracic echocardiogram (TTE) is a noninvasive technique that estimates CO. We aimed to describe if the TP can improve CO. MATERIALS AND METHODS: We conducted a descriptive study in healthy subjects (ASA I), with TTE measurements of CO and the End-Diastolic Volume of the Left Ventricle (EDVLV) in supine and after 5 minutes in TP. RESULTS: There showed no significant changes in blood pressure, heart rate and pulse oximetry in 0° and after 5 minutes in 45°. The mean CO without inclination was 4.2 l/min ± 0.6, tat is the same results after 5 minutes in PT (p > 0.6). The EDVLV was 95 ± 12 ml at 0° and 101 ± 15 ml after 5 minutes in PT (p > 0.8). CONCLUSION: Trendelenburg position doesn't improve CO or preload in healthy subjects.
INTRODUCCIÓN: Empíricamente se ha utilizado la posición de Trendelenburg (PT) para aumentar la precarga y posteriormente el gasto cardiaco (GC). La ecografía transtorácica (ETT) es una técnica no invasiva que puede estimar el GC. Realizamos un estudio descriptivo para evaluar si la PT afecta el CG. MATERIALES Y MÉTODOS: Examinamos pacientes ASA I, se hicieron mediciones del GC y del volumen de fin de diástole (VDFVI) en posición supina y luego de cinco minutos en PT. RESULTADOS: No se observaron cambios significativos en la presión arterial, frecuencia cardíaca y saturometría en los voluntarios a 0º y a 45º. El GC sin inclinación fue en promedio 4,2 l/min ± 0,6, el mismo resultado tras cinco minutos en PT, sin ser estadísticamente significativo (p > 0,6). El VDFVI a 0º fue en promedio 95 ± 12 ml y tras cinco minutos en PT 101 ± 15 ml, que tampoco alcanzó diferencia estadísticamente significativa (p > 0,8). CONCLUSIÓN: La posición de Trendelenburg no varía el gasto cardiaco ni la precarga en voluntarios sanos.
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Humanos , Masculino , Femenino , Adulto , Adulto Joven , Ecocardiografía/métodos , Gasto Cardíaco/fisiología , Inclinación de Cabeza , Volumen Sistólico/fisiología , Posicionamiento del Paciente , Presión Arterial/fisiología , Saturación de Oxígeno/fisiología , Frecuencia Cardíaca/fisiologíaRESUMEN
Introducción: Cada día resulta mayor la proporción de ancianos que asiste a los quirófanos. El manejo de estos pacientes ha ido evolucionando aparejadamente a las técnicas mínimamente invasivas, encaminadas a evitar la hospitalización, las complejas pruebas complementarias y los costosos tratamientos. Objetivo: Determinar los factores que repercuten en la hemodinamia del paciente geriátrico durante la colecistectomía laparoscópica. Material y Métodos: Se realizó un estudio prospectivo, longitudinal y analítico de 132 pacientes mayores de 60 años intervenidos por colecistectomía laparoscópica electiva, en el Hospital clínico-quirúrgico Julio Trigo López durante el período comprendido desde enero de 2014 hasta junio de 2016. Resultados: Predominó el grupo correspondiente a los 60 - 69 años de edad, el sexo femenino y el estado físico ASA II. El 75 por ciento de los pacientes no sufrió cambios hemodinámicos. Se presentó un 25 por ciento de variabilidades hemodinámicas predominantes en el grupo de 70-79 años de edad. La diferencia en la variabilidad hemodinámica entre los grupos etarios resultó altamente significativa. La hipertensión arterial (51,5 por ciento) y la taquicardia (27,3 por ciento) fueron las variaciones más frecuentes. Los factores determinantes en los cambios fueron dependientes del proceder quirúrgico: mayor presión intrabdominal posneumoperitoneo (22 por ciento) y Trendelenburg superior a 10 grados (93,9 por ciento). Conclusiones: Los factores determinantes en la hemodinamia fueron dependientes del acto quirúrgico. Se presentaron variaciones significativas entre los diferentes grupos etarios, sugiriendo cierta influencia del factor edad, pero la mayor longevidad no constituyó un aspecto decisivo. La colecistectomía laparoscópica es una valiosa alternativa terapéutica para los pacientes ancianos(AU)
Introduction: The number of elderly patients undergoing surgery is greater every day. The management of these patients has been evolving together with minimal invasive techniques, aimed at avoiding hospitalization, complex complementary tests, and expensive treatments. Objective: To determine the factors that have an effect on the hemodynamics of the geriatric patient during laparoscopic cholecystectomy. Material and Methods: A prospective, longitudinal, and analytic study was conducted in 132 patients older than 60 years of age who underwent elective laparoscopic cholecystectomy at the Julio Trigo López Clinical and Surgical Hospital during the period between January 2014 to June 2016. Results: Subjects aged 60 to 69 years, the female sex, and the physical state ASA II predominated in the study. 75% of these patients did not suffer hemodynamic changes. 25 percent of predominant hemodynamic variabilities were present especially in the group aged 70 to 79 years. The difference in hemodynamic variability between the age groups was highly significant. Arterial hypertension (51,5 percent and tachycardia (27,3 percent) were the most frequent variations. The determining factors in the changes were dependent on the surgical procedure: higher intra-abdominal pressure after pneumoperitoneum (22 percent) and Trendelenburg higher than 10 degrees (93.9 percent). Conclusions: The determining factors in hemodynamics were dependent on the surgical act. There were significant variations among the different age groups, suggesting a certain influence of the age factor, but the greatest longevity didn't constitute a decisive aspect. Laparoscopic cholecystectomy is a valuable therapeutic alternative for elderly patients(AU)
Asunto(s)
Humanos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Colecistectomía Laparoscópica/métodos , Inclinación de Cabeza/fisiología , Hemodinámica/fisiología , Estudios Prospectivos , Estudios LongitudinalesRESUMEN
Objetivou-se avaliar os efeitos do pneumoperitônio e da posição de Trendelenburg sobre o fluxo de saída do ventrículo esquerdo em gatos anestesiados. Quatorze gatos foram alocados aleatoriamente em dois grupos, ambos submetidos ao pneumoperitônio com 10mmHg de dióxido de carbono (CO2). No grupo controle (GC n=7), os animais foram submetidos apenas ao pneumoperitônio e, no grupo Trendelenburg (GTREN n=7), os animais foram colocados em cefalodeclive 20° após o pneumoperitônio. A indução anestésica foi realizada com isoflurano, utilizando-se caixa de indução. Posteriormente, os animais foram mantidos sob anestesia inalatória com o mesmo fármaco. Foram avaliados a velocidade do fluxo de saída do ventrículo esquerdo (VFSVE), os gradientes máximo (GmáxSVE) e médio (GmédSVE) de pressão e a integral velocidade-tempo (IVT). Os parâmetros foram mensurados nos momentos T0 (basal), antes da insuflação; T5 (cinco), T15 (quinze) e T30 (trinta) minutos após a insuflação. Os resultados mostraram um aumento da VFSVE no GC, em T15 e T30 (P=0,024), e um aumento do GmáxSVE no GC, em T30 (P=0,045). As variáveis não se alteraram significativamente em nenhum momento no GTREN. Dessa forma, conclui-se que a posição de Trendelenburg favoreceu o sistema cardiovascular, preservando os índices de fluxo sanguíneo na saída do ventrículo esquerdo.(AU)
The aim of this study was to evaluate the effects of pneumoperitoneum and Trendelenburg position on the left ventricular outflow in anesthetized cats. Fourteen cats were randomly divided into two groups, both submitted to pneumoperitoneum of 10 mmHg with carbon dioxide (CO2), and in the control group (GC n = 7) the animals were subjected only to pneumoperitoneum and the Trendelenburg group (n = 7 GTREN) the animals were placed in cefalodeclive 20° after pneumoperitoneum. Anesthesia of the animals was performed with isoflurane using induction box, keeping the animals under inhalation anesthesia with the same drug. We evaluated the speed of the left ventricular outflow (VFSVE), the maximum pressure gradient (GmáxSVE), mean pressure gradient (GmédSVE) and velocity-time integrals (IVT). The parameters were measured in time, T0 (baseline), before the insufflation; T5 (five); T15 (fifteen) and T30 (thirty) minutes after inflation. The results showed an increase in VFSVE in GC, T15 and T30 (p = 0,024) and an increase in GmáxSVE in GC in T30 (p = 0,045). The variables did not change significantly at any time in GTREN. Thus, it is concluded that the Trendelenburg position favored the cardiovascular system, preserving blood flow rates in the left ventricular outflow.(AU)
Asunto(s)
Animales , Gatos , Inclinación de Cabeza , Neumoperitoneo/veterinaria , Ventrículos Cardíacos , Dióxido de Carbono/fisiología , Isoflurano/uso terapéutico , Anestesia Local/veterinaria , Ultrasonografía Doppler de Pulso/veterinariaRESUMEN
Objetivou-se avaliar os efeitos do pneumoperitônio e da posição de Trendelenburg sobre o fluxo de saída do ventrículo esquerdo em gatos anestesiados. Quatorze gatos foram alocados aleatoriamente em dois grupos, ambos submetidos ao pneumoperitônio com 10mmHg de dióxido de carbono (CO2). No grupo controle (GC n=7), os animais foram submetidos apenas ao pneumoperitônio e, no grupo Trendelenburg (GTREN n=7), os animais foram colocados em cefalodeclive 20° após o pneumoperitônio. A indução anestésica foi realizada com isoflurano, utilizando-se caixa de indução. Posteriormente, os animais foram mantidos sob anestesia inalatória com o mesmo fármaco. Foram avaliados a velocidade do fluxo de saída do ventrículo esquerdo (VFSVE), os gradientes máximo (GmáxSVE) e médio (GmédSVE) de pressão e a integral velocidade-tempo (IVT). Os parâmetros foram mensurados nos momentos T0 (basal), antes da insuflação; T5 (cinco), T15 (quinze) e T30 (trinta) minutos após a insuflação. Os resultados mostraram um aumento da VFSVE no GC, em T15 e T30 (P=0,024), e um aumento do GmáxSVE no GC, em T30 (P=0,045). As variáveis não se alteraram significativamente em nenhum momento no GTREN. Dessa forma, conclui-se que a posição de Trendelenburg favoreceu o sistema cardiovascular, preservando os índices de fluxo sanguíneo na saída do ventrículo esquerdo.(AU)
The aim of this study was to evaluate the effects of pneumoperitoneum and Trendelenburg position on the left ventricular outflow in anesthetized cats. Fourteen cats were randomly divided into two groups, both submitted to pneumoperitoneum of 10 mmHg with carbon dioxide (CO2), and in the control group (GC n = 7) the animals were subjected only to pneumoperitoneum and the Trendelenburg group (n = 7 GTREN) the animals were placed in cefalodeclive 20° after pneumoperitoneum. Anesthesia of the animals was performed with isoflurane using induction box, keeping the animals under inhalation anesthesia with the same drug. We evaluated the speed of the left ventricular outflow (VFSVE), the maximum pressure gradient (GmáxSVE), mean pressure gradient (GmédSVE) and velocity-time integrals (IVT). The parameters were measured in time, T0 (baseline), before the insufflation; T5 (five); T15 (fifteen) and T30 (thirty) minutes after inflation. The results showed an increase in VFSVE in GC, T15 and T30 (p = 0,024) and an increase in GmáxSVE in GC in T30 (p = 0,045). The variables did not change significantly at any time in GTREN. Thus, it is concluded that the Trendelenburg position favored the cardiovascular system, preserving blood flow rates in the left ventricular outflow.(AU)
Asunto(s)
Animales , Gatos , Dióxido de Carbono/fisiología , Inclinación de Cabeza , Ventrículos Cardíacos , Isoflurano/uso terapéutico , Neumoperitoneo/veterinaria , Anestesia Local/veterinaria , Ultrasonografía Doppler de Pulso/veterinariaRESUMEN
OBJECTIVE: To assess the cardiopulmonary effects caused by reverse Trendelenburg position (RTP) at 5° and 10° in sevoflurane-anesthetized yearling steers. STUDY DESIGN: Prospective, experimental study. ANIMALS: Eight Holstein steers aged (mean ± standard deviation) 12 ± 2 months and weighing 145 ± 26 kg. METHODS: In the first phase of the study, the individual minimum alveolar concentration (MAC) of sevoflurane was determined using electrical stimulation. In the second phase, the effects of RTP were assessed. The animals were anesthetized on three separate events separated by ≥7 days in an incomplete crossover design: control treatment using a table without tilt (RTP0); treatment with the table at 5° RTP (RTP5) and table tilted 10° RTP (RTP10). Subjects were physically restrained in dorsal recumbency on the table, which was already tilted according to each treatment. Anesthesia was induced with sevoflurane at 8% in 5 L minute-1 oxygen via face mask followed by maintenance with sevoflurane at 1.3 MAC and spontaneous breathing. Cardiopulmonary variables were obtained immediately after instrumentation (T0) and then after 30, 60, 120 and 180 minutes (T30, T60, T120 and T180, respectively). RESULTS: The mean sevoflurane MAC for the eight steers was 2.12 ± 0.31%. Cardiac output was lower at all time points and the systemic vascular resistance index was higher at T120 and T180 in RTP10 compared with RTP0. Oxygen consumption was lower at T0 and at T180 in RTP10 compared with RTP0 and at all time points except T30 compared with RTP5. Oxygen extraction was lower at T0 in RTP10 compared with RTP0 and RTP5, and at T60 and T180 compared with RTP5. CONCLUSIONS AND CLINICAL RELEVANCE: RTP 5° and 10° did not improve ventilatory and oxygenation variables in sevoflurane-anesthetized steers when compared with no tilt, however the cardiovascular variables were adversely affected in RTP10.
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Anestesia por Inhalación/veterinaria , Anestésicos por Inhalación , Inclinación de Cabeza/fisiología , Corazón/fisiología , Éteres Metílicos , Fenómenos Fisiológicos Respiratorios , Anestesia por Inhalación/métodos , Anestésicos por Inhalación/análisis , Animales , Análisis de los Gases de la Sangre/veterinaria , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Bovinos , Estudios Cruzados , Corazón/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Masculino , Éteres Metílicos/análisis , Alveolos Pulmonares/química , Fenómenos Fisiológicos Respiratorios/efectos de los fármacos , Sevoflurano , Volumen de Ventilación Pulmonar/efectos de los fármacos , Volumen de Ventilación Pulmonar/fisiologíaRESUMEN
Background: Zinc and copper have many physiologic functions and little or no functional storage capability, so persistent losses of either element present health concerns, especially during extended-duration space missions.Objectives: We evaluated the effects of short-term bed rest (BR), a spaceflight analog, on copper and zinc metabolism to better understand the role of these nutrients in human adaptation to (simulated) spaceflight. We also investigated the effect of artificial gravity on copper and zinc homeostasis.Methods: Zinc and copper balances were studied in 15 men [mean ± SD age: 29 ± 3 y; body mass index (in kg/m2): 26.4 ± 2.2] before, during, and after 21 d of head-down tilt BR, during which 8 of the participants were subjected to artificial gravity (AG) by centrifugation for 1 h/d. Control subjects were transferred onto the centrifuge but were not exposed to centrifugation. The study was conducted in a metabolic ward; all urine and feces were collected. Data were analyzed by 2-factor repeated-measures ANOVA.Results: Urinary zinc excretion values for control and AG groups were 33% and 14%, respectively, higher during BR than before BR, and fecal zinc excretion values for control and AG groups were 36% and 19%, respectively, higher during BR, resulting in 67% and 82% lower net zinc balances for controls and AG, respectively (both P < 0.01), despite lower nutrient intake during BR. Fecal copper values for control and AG groups were 40% and 33%, respectively, higher during BR than before BR (P < 0.01 for both). Urinary copper did not change during BR, but a 19% increase was observed after BR compared with before BR in the AG group (P < 0.05).Conclusions: The increased fecal excretion of copper and zinc by men during BR suggests that their absorption of these minerals from the diet was reduced, secondary to the release of minerals from bone and muscle. These findings highlight the importance of determining dietary requirements for astronauts on space missions and ensuring provision and intake of all nutrients.