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BACKGROUND: Robotic surgery is a valid option for minimally invasive surgery in most surgical specialties. However, the need to master laparoscopy is questionable before starting specific training in robotic surgery. We compared the development of basic robotic surgery skills between individuals randomized to train in conventional, laparoscopic, or robotic skills. METHODS: We conducted a single-centered, single-blinded randomized trial. Medical students were randomly assigned to 20 h of conventional, laparoscopic, or robotic surgical training. Students with previous surgical experience were excluded. Participants were evaluated pre- and post-training on the dV-Trainer robotic surgical simulator with the following exercises: Camera Targeting 1, Peg Board 1, Ring and Rail 1, and Ring and Rail 2. RESULTS: Sixty-six students were randomly assigned to each training group. Eight individuals did not complete the study (2 in the conventional group, 3 in the laparoscopic group, and 3 in the robotic group). All groups demonstrated significant improvement in the composite score and in each task following the training period (p < 0.001). No differences were seen between the conventional and laparoscopic groups in the composite score or individual tasks. The robotic group showed greater improvement in number of errors, economy of motion, workspace utilization, and time for completion compared to the other groups. The laparoscopic group showed improved camera manipulation skills compared to the conventional group, while the conventional group showed improved errors and economy of motion compared to the laparoscopic group. CONCLUSION: There was no difference in the acquisition of basic robotic surgical skills between individuals trained in basic conventional or laparoscopic surgical skills. We believe surgeons mastery in laparoscopy is not needed before initiating robotic surgical training. However, basic principles of laparoscopy remain applicable to robotic surgery. Future studies should compare transferability of conventional and laparoscopic training to robotic skills in the operating room.
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Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Entrenamiento Simulado , Competencia Clínica , Simulación por Computador , Humanos , Laparoscopía/educación , Procedimientos Quirúrgicos Robotizados/educación , Robótica/educaciónRESUMEN
Ex vivo heart perfusion has been shown to be an effective means of facilitating the resuscitation and assessment of donor hearts for cardiac transplantation. Over the last ten years however, only a few ex vivo perfusion systems have been developed for this application. While results have been promising, a system capable of facilitating multiple perfusion strategies on the same platform has not yet been realized. In this paper, the design, development and testing of a novel and modular ex vivo perfusion system is described. The system is capable of operating in three unique primary modes: the traditional Langendorff Mode, Pump-Supported Working-Mode, and Passive Afterload Working-Mode. In each mode, physiological hemodynamic parameters can be produced by managing perfusion settings. To evaluate heart viability, six experiments were conducted using porcine hearts and measuring several parameters including: pH, aortic pressure, lactate metabolism, coronary vascular resistance (CVR), and myocardial oxygen consumption. Pressure-volume relationship measurements were used to assess left ventricular contractility in each Working Mode. Hemodynamic and metabolic conditions remained stable and consistent across 4 h of ex vivo heart perfusion on the ex vivo perfusion system, validating the system as a viable platform for future development of novel preservation and assessment strategies.
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Diseño de Equipo , Corazón/fisiología , Perfusión/métodos , Animales , Trasplante de Corazón/métodos , Hemodinámica , Concentración de Iones de Hidrógeno , Ácido Láctico/metabolismo , Consumo de Oxígeno , PorcinosRESUMEN
BACKGROUND: Ghrelin, a novel growth hormone-releasing peptide, has both anti-inflammatory and anti-apoptotic effects on human endothelial cells. We evaluated the protective effects of ghrelin against ischemia-reperfusion injury (IRI) in a murine heterotopic cervical heart transplantation model. METHODS: Donor hearts from C57BL/6J wild-type mice, which were kept in cold saline for 60 minutes, were heterotopically transplanted into C57BL/6J wild-type recipients. A day prior to heterotopic cervical heart transplantation, donor animals received either ghrelin (300 nmol/kg) or saline (0.3 mL) intraperitoneally. Upon reperfusion and postoperative day 1, ghrelin or saline was administered to the recipients. Donor hearts were procured on day 2. RESULTS: Ghrelin injection did not result in any adverse effects in donors or recipients. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive cells were significantly decreased in the ghrelin group (0.38% ± 0.21% vs 5.74% ± 3.68%; P < .001). Both cleaved caspase-3 activity and Bcl-2/Bax ratio from the ghrelin group were significantly reduced compared to those in the control. Furthermore, the phosphorylated Akt/Akt ratio was higher in the ghrelin group (0.44 ± 0.21 vs 0.14 ± 0.03; P = .043). Nuclear factor-kappa B p65 nuclear translocation was reduced in the ghrelin hearts compared to the controls (3.17% ± 1.84% vs 19.28% ± 13.14%; P = .009). Vascular cell adhesion molecule-1, intracellular adhesion molecule-1, nuclear factor-kappa B, and tumor necrosis factor alpha levels were also significantly reduced in the ghrelin-treated group. No significant difference was observed in 8-isoprostane production between groups. CONCLUSION: Ghrelin inhibits the inflammatory response and apoptosis during transplant-related IRI. This study demonstrates the protective effects of ghrelin against IRI.
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Ghrelina , Trasplante de Corazón , Daño por Reperfusión , Animales , Humanos , Ratones , Apoptosis , Células Endoteliales , Ghrelina/farmacología , Ratones Endogámicos C57BL , FN-kappa B , Proteínas Proto-Oncogénicas c-akt , Daño por Reperfusión/patologíaRESUMEN
Ex situ heart perfusion (ESHP) was developed to preserve and evaluate donated hearts in a perfused beating state. However, myocardial function declines during ESHP, which limits the duration of perfusion and the potential to expand the donor pool. In this research, we combine a novel, minimally-invasive sampling approach with comparative global metabolite profiling to evaluate changes in the metabolomic patterns associated with declines in myocardial function during ESHP. Biocompatible solid-phase microextraction (SPME) microprobes serving as chemical biopsy were used to sample heart tissue and perfusate in a translational porcine ESHP model and a small cohort of clinical cases. In addition, six core-needle biopsies of the left ventricular wall were collected to compare the performance of our SPME sampling method against that of traditional tissue-collection. Our state-of-the-art metabolomics platform allowed us to identify a large number of significantly altered metabolites and lipid species that presented comparable profile of alterations to conventional biopsies. However, significant discrepancies in the pool of identified analytes using two sampling methods (SPME vs. biopsy) were also identified concerning mainly compounds susceptible to dynamic biotransformation and most likely being a result of low-invasive nature of SPME. Overall, our results revealed striking metabolic alterations during prolonged 8h-ESHP associated with uncontrolled inflammation not counterbalanced by resolution, endothelial injury, accelerated mitochondrial oxidative stress, the disruption of mitochondrial bioenergetics, and the accumulation of harmful lipid species. In conclusion, the combination of perfusion parameters and metabolomics can uncover various mechanisms of organ injury and recovery, which can help differentiate between donor hearts that are transplantable from those that should be discarded.
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Trasplante de Corazón , Animales , Trasplante de Corazón/métodos , Humanos , Lípidos , Miocardio/patología , Perfusión/métodos , Porcinos , Donantes de TejidosRESUMEN
Ex situ heart perfusion (ESHP) has been developed to decrease cold ischemia time and allow metabolic assessment of donor hearts prior to transplantation. Current clinical ESHP systems preserve the heart in an unloaded condition and only evaluate the cardiac metabolic profile. In this pilot study we performed echocardiographic functional assessment using two alternative systems for left ventricular (LV) loading: pump supported afterload working mode (SAM) and passive afterload working modes (PAM). Six hearts were procured from male Yorkshire pigs. During cold ischemia, hearts were mounted on our custom made ESHP circuit and a 3D-printed enclosure for the performance of echocardiography with a standard TEE probe. Following perfusion with Langherdorf mode of the unloaded heart, the system was switched into different working modes to allow LV loading and functional assessment: pump supported (SAM) and passive (PAM). Echocardiographic assessment of left ventricular function in the donor hearts was performed in vivo and at 1 h of ESHP with SAM, after 4.5 h with PAM and after 5.5 h with SAM. We obtained good quality epicardial echocardiographic images at all time points allowing a comprehensive LV systolic assessment. All indices showed a decrease in LV systolic function throughout the trial with the biggest drop after heart harvesting. We demonstrated the feasibility of echocardiographic functional assessment during ESHP and two different working modes. The expected LV systolic dysfunction consisted of a reduction in EF, FAC, FS, and strain throughout the experiment with the most significant decrease after harvesting.
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PURPOSE: To evaluate the influence of ocular axial length on circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness in healthy eyes after correcting for ocular magnification effect. METHODS: In this cross-sectional study, we evaluated 120 eyes from 60 volunteer participants (myopes, emmetropes, and hyperopes). The thickness of the circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer were measured using the spectral optical coherence tomography (OCT)-Cirrus HD-OCT and correlated with ocular axial length. Adjustment for ocular magnification was performed by applying Littmann's formula. RESULTS: Before the adjustment for ocular magnification, age-adjusted mixed models analysis demonstrated a significant negative correlation between axial length and average circumpapillary retinal nerve fiber layer thickness (r=-0.43, p<0.001), inferior circumpapillary retinal nerve fiber layer thickness (r=-0.46, p<0.001), superior circumpapillary retinal nerve fiber layer thickness (r=-0.31, p<0.05), nasal circumpapillary retinal nerve fiber layer thickness (r=-0.35, p<0.001), and average ganglion cell-inner plexiform layer thickness (r=-0.35, p<0.05). However, after correcting for magnification effect, the results were considerably different, revealing only a positive correlation between axial length and temporal retinal nerve fiber layer thickness (r=0.42, p<0.001). Additionally, we demonstrated a positive correlation between axial length and average ganglion cell-inner plexiform layer thickness (r=0.48, p<0.001). All other correlations were not found to be statistically significant. CONCLUSIONS: Before adjustment for ocular magnification, axial length was negatively correlated with circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness measured by Cirrus-OCT. We attributed this effect to ocular magnification associated with greater axial lengths, which was corrected with the Littman's formula. Further studies are required to investigate the impact of ocular magnification correction on the diagnostic accuracy of Cirrus-OCT.
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Tomografía de Coherencia Óptica , Estudios Transversales , Glaucoma , Humanos , Fibras Nerviosas , Células Ganglionares de la RetinaRESUMEN
BACKGROUND: The interactive relationship between left ventricular (LV) ejection fraction (LVEF) and LV size in predicting perioperative outcomes after cardiac surgery has not been clarified. METHODS: This study reviewed all patients who underwent cardiac surgery between 2010 and 2016 with either preserved LVEF (>60%; n = 5685) or severely reduced LVEF (<20%; n = 143). LV size was categorized by using either LV end-diastolic or end-systolic diameter or a qualitative assessment, as follows: normal, smaller than 4 cm; mildly enlarged, 4.1 to 5.4 cm moderately enlarged, 5.5 to 6.5 cm; and severely enlarged, larger than 6.5 cm. Using propensity-score analysis, we matched patients with LVEF less than 20% (n = 143) in a 3:1 ratio with patients with LVEF greater than 60% (n = 429). RESULTS: There were significant differences in mortality, major morbidity, and operative mortality and prolonged length of stay between patients with LVEF less than 20% and LVEF greater than 60%. In patients with LVEF less than 20%, there were no significant differences in outcomes between those with an LV size of 5.4 cm or smaller and an LV size of 5.5 cm or larger. In patients undergoing isolated coronary artery bypass grafting (CABG), LV size predicted mortality, major morbidity, and operative mortality (odds ratio, 5.5 [95% confidence interval, 2.0 to 15.7]; P < .001) and prolonged length of stay (odds ratio, 3.4 [95% confidence interval, 1.2 to 10.3]; P = .026), respectively. CONCLUSIONS: LVEF is more important than LV size in predicting outcomes after cardiac surgery. However, in patients undergoing isolated CABG, LV size has an interactive effect with LVEF and can potentially aid the decision-making process. Risk adjustment models using only LVEF may be inaccurate, particularly with respect to isolated CABG procedures.
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Puente de Arteria Coronaria/efectos adversos , Enfermedad de la Arteria Coronaria/cirugía , Ventrículos Cardíacos/diagnóstico por imagen , Complicaciones Posoperatorias , Volumen Sistólico/fisiología , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda/fisiología , Anciano , Diástole , Ecocardiografía , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Periodo Posoperatorio , Puntaje de Propensión , Estudios Retrospectivos , Factores de Riesgo , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/etiologíaRESUMEN
OBJECTIVES: There is an increasing proportion of patients with a previous sternotomy (PS) or durable left ventricular assist device (LVAD) undergoing heart transplantation (HT). We hypothesized that patients with LVAD support at the time of HT have a lower risk than patients with PS and may have a comparable risk to patients with a virgin chest (VC). METHODS: This is a single-centre retrospective cohort study of all adults who underwent primary single-organ HT between 2002 and 2017. Multivariable Cox regression analyses were performed to compare 30-day and 1-year mortality between transplanted patients with a VC (VC-HT), a PS (PS-HT) or an LVAD explant (LVAD-HT). RESULTS: Three hundred seventy-nine patients were analysed (VC-HT: 196, PS-HT: 94, LVAD-HT: 89). A larger proportion of patients in the LVAD-HT group were males (83%), had blood group O (52%), non-ischaemic aetiology (70%) and sensitization (67%). The PS-HT group had a higher frequency of patients with congenital heart disease (30%) and PSs compared to LVAD-HT patients (P < 0.001). PS-HT and LVAD-HT patients required a longer bypass time (P < 0.001) and showed a greater estimated blood loss (P < 0.001). Postoperatively, LVAD-HT required haemodialysis more frequently than the VC-HT group (P = 0.031). Multivariable analyses found that PS-HT patients had increased 30-day mortality compared to VC-HT [hazard ratio (HR) 2.63, 95% confidence interval (CI) 1.15-6.01; P = 0.022] while LVAD-HT did not (HR 2.17, 95% CI 0.96-4.93; P = 0.064). At 1-year, neither PS-HT nor LVAD-HT groups were significantly associated with increased mortality compared to VC-HT. CONCLUSIONS: Transplants in recipients with PS-HT demonstrated increased early mortality compared to VC-HT patients. Although LVAD explant is often technically challenging, this population demonstrated similar mortality compared to those VC-HT patients. The chronic and perioperative support provided by the LVAD may play a favourable role in early patient outcomes compared to other redo sternotomy patients.
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Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/mortalidad , Corazón Auxiliar/efectos adversos , Esternotomía/efectos adversos , Adulto , Femenino , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Reoperación/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: Ex situ heart perfusion (ESHP) limits ischemic periods and enables continuous monitoring of donated hearts; however, a validated assessment method to predict cardiac performance has yet to be established. We compare biventricular contractile and metabolic parameters measured during ESHP to determine the best evaluation strategy to estimate cardiac function following transplantation. METHODS: Donor pigs were assigned to undergo beating-heart donation (n = 9) or donation after circulatory death (n = 8) induced by hypoxia. Hearts were preserved for 4 hours with ESHP while invasive and noninvasive (NI) biventricular contractile, and metabolic assessments were performed. Following transplantation, hearts were evaluated at 3 hours of reperfusion. Spearman correlation was used to determine the relationship between ESHP parameters and posttransplant function. RESULTS: We performed 17 transplants; 14 successfully weaned from bypass (beating-heart donation versus donation after circulatory death; P = 0.580). Left ventricular invasive preload recruitable stroke work (PRSW) (r = 0.770; P = 0.009), NI PRSW (r = 0.730; P = 0.001), and NI maximum elastance (r = 0.706; P = 0.002) strongly correlated with cardiac index (CI) following transplantation. Right ventricular NI PRSW moderately correlated to CI following transplantation (r = 0.688; P = 0.003). Lactate levels were weakly correlated with CI following transplantation (r = -0.495; P = 0.043). None of the echocardiography measurements correlated with cardiac function following transplantation. CONCLUSIONS: Left ventricular functional parameters, especially ventricular work and reserve, provided the best estimation of myocardial performance following transplantation. Furthermore, simple NI estimates of ventricular function proved useful in this setting. Right ventricular and metabolic measurements were limited in their ability to correlate with myocardial recovery. This emphasizes the need for an ESHP platform capable of assessing myocardial contractility and suggests that metabolic parameters alone do not provide a reliable evaluation.
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Trasplante de Corazón/métodos , Preservación de Órganos/métodos , Perfusión , Donantes de Tejidos , Función Ventricular Izquierda/fisiología , Animales , Ecocardiografía , Masculino , Contracción Miocárdica , Miocardio/metabolismo , PorcinosRESUMEN
PURPOSE: Windkessel impedance analysis has proven to be an effective technique for instituting artificial afterload on ex situ hearts. Traditional fixed parameter afterload modules, however, are unable to handle the changing contractile conditions associated with prolonged ex situ heart perfusion. In this paper, an adjustable afterload module is described comprising of three fully adjustable sub-components: a systemic resistor, a proximal resistor and a compliance chamber. METHODS: Using a centrifugal pump, the systemic resistor and compliance chamber were subjected to testing across their operating ranges, whereby the predictability of resistance and compliance values was evaluated. The components were then assembled, and the full module tested on three separate porcine hearts perfused for 6 h with success defined by the ability to maintain physiological systolic and diastolic aortic pressures across flow rate variability. RESULTS: For both the systemic resistor and compliance chamber, experimental measurements agreed with their theoretical equivalents, with coefficients of determination of 0.99 and 0.97 for the systemic resistor and compliance chamber, respectively. During ex situ perfusion, overall 95% confidence intervals demonstrate that physiological systolic (95-96.21 mmHg) and diastolic (26.8-28.8 mmHg) pressures were successfully maintained, despite large variability in aortic flow. Left ventricular contractile parameters, were found to be in line with those in previous studies, suggesting the afterload module has no detrimental impact on functional preservation. CONCLUSIONS: We conclude that due to the demonstrable control of our afterload module, we can maintain physiological aortic pressures in a passive afterload working mode across prolonged perfusion periods, enabling effective perfusion regardless of contractile performance.
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Aorta/fisiopatología , Presión Arterial , Modelos Cardiovasculares , Contracción Miocárdica , Perfusión , Función Ventricular Izquierda , Animales , Adaptabilidad , Módulo de Elasticidad , Preparación de Corazón Aislado , Masculino , Modelos Animales , Sus scrofa , Factores de TiempoRESUMEN
Cardiac transplantation demand is on the rise; nevertheless, organ availability is limited due to a paucity of suitable donors. Organ donation after circulatory death (DCD) is a solution to address this limited availability, but due to a period of prolonged warm ischemia and the risk of tissue injury, its routine use in cardiac transplantation is seldom seen. In this manuscript we provide a detailed protocol closely mimicking current clinical practices in the context of DCD with continuous monitoring of heart function, allowing for the evaluation of novel cardioprotective strategies and interventions to decrease ischemia-reperfusion injury. In this model, the DCD protocol is initiated in anesthetized Lewis rats by stopping ventilation to induce circulatory death. When systolic blood pressure drops below 30 mmHg, the warm ischemic time is initiated. After a pre-set warm ischemic period, hearts are flushed with a normothermic cardioplegic solution, procured, and mounted onto a Langendorff ex vivo heart perfusion system. Following 10 min of initial reperfusion and stabilization, cardiac reconditioning is continuously evaluated for 60 min using intraventricular pressure monitoring. A heart injury is assessed by measuring cardiac troponin T and the infarct size is quantified by histological staining. The warm ischemic time can be modulated and tailored to develop the desired amount of structural and functional damage. This simple protocol allows for the evaluation of different cardioprotective conditioning strategies introduced at the moment of cardioplegia, initial reperfusion and/or during ex vivo perfusion. Findings obtained from this protocol can be reproduced in large models, facilitating clinical translation.
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Trasplante de Corazón/métodos , Obtención de Tejidos y Órganos , Animales , Paro Cardíaco Inducido , Modelos Animales , Perfusión/métodos , Ratas , Ratas Endogámicas Lew , Daño por Reperfusión/prevención & control , Isquemia TibiaRESUMEN
OBJECTIVE: To evaluate and compare the eruption rates of lower second premolars (LPm2) at different developmental stages using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Retrospectively, 31 individuals (9.77 ± 1.25 years) had their LPm2 scored according to the Demirjian method, and afterwards they were split into three groups according to developmental stage, as follows: D = complete-formed crowns; E = root length less than crown height; and F = root length greater than or equal to crown height. Linear distances from the LPm2 crown tip to the anatomical reference line (ARL) and to the occlusal plane line (OPL) were measured in paired CBCT scans (T1, T2), taken with an average interval of 8.6 months between them. Eruption rates (mm/y) were calculated and then compared between groups. RESULTS: Eruption rates were greater for LPm2 at stage F than at stages D or E (P < .01) regardless of whether they were measured from the ARL (D = 2.84 mm/y; E = 2.55 mm/y; F = 5.38 mm/y) or from the OPL (D = 1.82 mm/y; E = 2.02 mm/y; F = 5.26 mm/y). Eruption rates evaluated from the ARL and the OPL had no statistically significant differences (P = .052), and a positive correlation (r = .79, P < .001) between them was observed. CONCLUSIONS: LPm2 at Demirjian stage F showed greater eruption rates than at stages D or E, regardless of whether rates were measured from the ARL or the OPL. Faster eruption is expected for LPm2 at stage F. Evaluation of the LPm2's developmental stage using CBCT can aid in clinical decision making regarding the correct timing for intervention.
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Diente Premolar/diagnóstico por imagen , Diente Premolar/crecimiento & desarrollo , Tomografía Computarizada de Haz Cónico , Erupción Dental , Niño , Femenino , Humanos , Masculino , Mandíbula , Estudios Retrospectivos , Corona del Diente/diagnóstico por imagen , Corona del Diente/crecimiento & desarrolloRESUMEN
BACKGROUND: Laparoscopic surgery is a reality in almost all surgical centers. Although with initial greater technical difficulty for surgeons, the rapid return to activities, less postoperative pain and higher quality aesthetic stimulates surgeons to evolve technically in this area. However, unlike open surgery where learning opportunities are more accessible, the laparoscopic training represents a challenge in surgeon formation. AIM: To present a low cost model for laparoscopic training box. METHODS: This model is based in easily accessible materials; the equipment can be easily found based on chrome mini jet and passes rubber thread and a webcam attached to an aluminum handle. RESULTS: It can be finalized in two days costing R$ 280,00 (US$ 90). CONCLUSION: It is possible to stimulate a larger number of surgeons to have self training in laparoscopy at low cost seeking to improve their surgical skills outside the operating room.
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Educación Médica/métodos , Laparoscopía/economía , Laparoscopía/educación , Entrenamiento Simulado , Costos y Análisis de CostoRESUMEN
ABSTRACT Purpose: To evaluate the influence of ocular axial length on circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness in healthy eyes after correcting for ocular magnification effect. Methods: In this cross-sectional study, we evaluated 120 eyes from 60 volunteer participants (myopes, emmetropes, and hyperopes). The thickness of the circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer were measured using the spectral optical coherence tomography (OCT)-Cirrus HD-OCT and correlated with ocular axial length. Adjustment for ocular magnification was performed by applying Littmann's formula. Results: Before the adjustment for ocular magnification, age-adjusted mixed models analysis demonstrated a significant negative correlation between axial length and average circumpapillary retinal nerve fiber layer thickness (r=-0.43, p<0.001), inferior circumpapillary retinal nerve fiber layer thickness (r=-0.46, p<0.001), superior circumpapillary retinal nerve fiber layer thickness (r=-0.31, p<0.05), nasal circumpapillary retinal nerve fiber layer thickness (r=-0.35, p<0.001), and average ganglion cell-inner plexiform layer thickness (r=-0.35, p<0.05). However, after correcting for magnification effect, the results were considerably different, revealing only a positive correlation between axial length and temporal retinal nerve fiber layer thickness (r=0.42, p<0.001). Additionally, we demonstrated a positive correlation between axial length and average ganglion cell-inner plexiform layer thickness (r=0.48, p<0.001). All other correlations were not found to be statistically significant. Conclusions: Before adjustment for ocular magnification, axial length was negatively correlated with circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness measured by Cirrus-OCT. We attributed this effect to ocular magnification associated with greater axial lengths, which was corrected with the Littman's formula. Further studies are required to investigate the impact of ocular magnification correction on the diagnostic accuracy of Cirrus-OCT.
RESUMO Objetivo: Avaliar a influência do comprimento axial ocular na espessura da camada de fibras nervosas da retina peripapilar e na espessura da camada de células ganglionares-plexiforme interna em olhos saudáveis após correção para efeito de magnificação ocular. Métodos: Neste estudo transversal, avaliamos 120 olhos de 60 participantes voluntários (míopes, emétropes e hipermétropes). A espessura da camada de fibras nervosas da retina peripapilar e da camada de células ganglionares-plexiforme interna foram medidas usando a tomografia de coerência óptica espectral (OCT)-Cirrus HD-OCT e correlacionada com o comprimento axial ocular. O ajuste para a magnificação ocular foi realizado aplicando a fórmula de Littmann. Resultados: Antes do ajuste para magnificação ocular, a análise de modelos mistos ajustada por idade demonstrou uma correlação negativa significante entre o comprimento axial e a espessura média da camada de fibras nervosas da retina peripapilar (r=-0,43; p<0,001), espessura da camada de fibras nervosas da retina peripapilar inferior (r=-0,46; p <0,001), espessura da camada de fibras nervosas da retina peripapilar superior (r=-0,31; p<0,05), espessura da camada de fibras nervosas da retina peripapilar nasal (r=-0,35; p<0,001) e espessura média das células ganglionares-plexiforme interna (r=-0,35; p<0,05). No entanto, após a correção do efeito de magnificação, os resultados foram consideravelmente diferentes, revelando apenas uma correlação positiva entre o comprimento axial e a espessura temporal da camada de fibras nervosas da retina(r=0,42; p<0,001). Além disso, demonstramos uma correlação positiva entre o comprimento axial e a espessura média das células ganglionares-plexiforme interna (r=0,48; p<0,001). Todas as outras correlações não foram consideradas estatisticamente significativas. Conclusão: Antes do ajuste para o efeito de magnificação ocular, o comprimento axial estava negativamente correlacionado com a espessura da camada de fibras nervosas da retina peripapilar e das células ganglionares-plexiforme interna medido pelo Cirrus-OCT. Atribuimos esse efeito à magnificação ocular associada a comprimentos axiais maiores, o que foi corrigido com a fórmula de Littman. Mais estudos são necessários para investigaro impactoda correçãoda magnificação ocular na acurácia diagnóstica do Cirrus-OCT.
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Humanos , Tomografía de Coherencia Óptica , Células Ganglionares de la Retina , Glaucoma , Estudios Transversales , Fibras NerviosasRESUMEN
PURPOSE: The aim of this study was to evaluate echocardiography-based indices of myocardial function and markers of vascular inflammation and endothelial dysfunction in the early phases of severe sepsis. MATERIAL AND METHODS: Forty-five adult patients (67% women; age 51 ± 18 years; Acute Physiology and Chronic Health Disease Classification System II score, 23 ± 7) admitted to the intensive care unit up to 24 hours after fulfilling criteria for severe sepsis or septic shock were studied. Clinical, laboratorial (endothelin 1 [ET1], vascular cellular adhesion molecule 1), and echocardiographic data were collected within the first 24 hours and again 72 hours and 7 days after admission. RESULTS: Intrahospital mortality was 33% (15 deaths). Left ventricular (LV) dysfunction (LV ejection fraction <55%) was identified in 15 (33%) patients, whereas right ventricular (RV) dysfunction (RV tissue Doppler peak systolic velocity [RV-Sm] <12 cm/s) was present in 14 (30%) patients. LogET1 was increased in patients with LV dysfunction (2.3 ± 0.6 vs 1.8 ± 0.4 pg/mL; P = .01) and RV dysfunction (2.5 ± 0.5 vs 1.8 ± 0.4 pg/mL; P < .001) and had negative correlations with LV ejection fraction (r = -0.50; P = .002) and RV-Sm (r = -0.67; P < .001). Left ventricular end-diastolic diameter, RV-Sm, and diastolic dysfunction were able to discriminate survivors from nonsurvivors, and the combination of these parameters identified groups of very low and high risk. CONCLUSION: Both LV and RV systolic dysfunctions are prevalent in severe sepsis, being directly associated with markers of endothelial dysfunction. Left ventricular nondilation, RV dysfunction, and diastolic dysfunction seem related to poor prognosis in this scenario.
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Cardiomiopatía Dilatada/etiología , Endotelio Vascular/fisiopatología , Sepsis/complicaciones , Sepsis/mortalidad , Disfunción Ventricular/etiología , Biomarcadores/sangre , Brasil/epidemiología , Cardiomiopatía Dilatada/diagnóstico por imagen , Ecocardiografía , Endotelina-1/sangre , Femenino , Humanos , Molécula 1 de Adhesión Intercelular/sangre , Masculino , Persona de Mediana Edad , Pronóstico , Sepsis/diagnóstico , Choque Séptico/complicaciones , Choque Séptico/diagnóstico , Choque Séptico/mortalidad , Tasa de Supervivencia , Disfunción Ventricular/diagnóstico por imagenRESUMEN
Background: Laparoscopic surgery is a reality in almost all surgical centers. Although with initial greater technical difficulty for surgeons, the rapid return to activities, less postoperative pain and higher quality aesthetic stimulates surgeons to evolve technically in this area. However, unlike open surgery where learning opportunities are more accessible, the laparoscopic training represents a challenge in surgeon formation.Aim:To present a low cost model for laparoscopic training box. Methods: This model is based in easily accessible materials; the equipment can be easily found based on chrome mini jet and passes rubber thread and a webcam attached to an aluminum handle. Results: It can be finalized in two days costing R$ 280,00 (US$ 90). Conclusion: It is possible to stimulate a larger number of surgeons to have self training in laparoscopy at low cost seeking to improve their surgical skills outside the operating room.
Racional:A cirurgia laparoscópica já é realidade em praticamente todos os centros cirúrgicos. Muito embora haja maior dificuldade técnica, o rápido retorno às atividades, menor dor pós-operatória e maior qualidade estética estimulam os cirurgiões a evoluírem tecnicamente nesta área. Porém, ao contrário das operações abertas onde as oportunidades de aprendizagem são mais acessíveis, o treinamento laparoscópico acaba sendo desafio ao longo da formação de um cirurgião.Objetivo:Apresentar um modelo de caixa de treinamento laparoscópico de baixo custo. Métodos:Foram utilizados materiais de fácil acesso, mini jato cromado, passa fios de borracha e uma webcam acoplada a um cabo de alumínio.Resultados:A white box foi produzida em dois dias com custo de R$ 280,00. Conclusão:É possível estimular o treinamento de maior número de cirurgiões na formação laparoscópica a baixo custo e buscar aperfeiçoamento de suas habilidades cirúrgicas fora do centro cirúrgico.