Browsing by Author "Meissner, Arturo"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Dexmedetomidine ameliorates gut lactate production and impairment of exogenous lactate clearance in an endotoxic sheep model
    (2015) Hernández P., Glenn; Tapia, Pablo; Bruhn, Alejandro; Soto, Dagoberto; Alegría, Leyla; Jarufe Cassis, Nicolás; Menchaca, Rodrigo; Meissner, Arturo; Vives, María Ignacia; Ospina Tascón, Gustavo A.; Luengo, Cecilia; Bakker, Jan
  • No Thumbnail Available
    Item
    Do Patients Older Than 60 Years With Inflammatory Bowel Disease Have More Vertebral Fractures Than Age-matched Controls? A Study Using Abdominal and Pelvic CT Scans With Sagittal Reformatting as Screening Tool.
    (2020) Besa Vial, Pablo José; Meissner, Arturo; Ledermann, Gerardo; Pérez Valenzuela, Javier; Vergara López, María; Álvarez Lobos, Manuel; Urrutia Escobar, Julio Octavio
    Introduction: Inflammatory bowel disease (IBD) has been associated with metabolic bone disease and increased fractures. This association is directly influenced by the disease and indirectly influenced by treatment. Therefore, patients with IBD could develop an elevated risk of osteoporotic fractures, particularly vertebral compression fractures (VCFs); however, symptomatic VCFs have not been shown to be more common in these patients. Our study evaluated the prevalence of VCF, independent of the presence of spinal symptoms, in IBD patients. Methods: We assessed IBD patients previously enrolled in a prospective cohort. All patients from that cohort who underwent computed tomography (CT) scans for nonspinal conditions were evaluated to detect the presence of VCFs. VCFs were classified using the Genant scheme. We evaluated whether patients with or without VCF differed in demographic data, type of IBD, treatment received and time from diagnosis. We used logistic regression to assess the independent effect of each variable. Results: In total, 6.5% of these patients had at least one VCF. Most fractures were Genant I (77%) and mostly at the thoracolumbar junction (T11 to L2, 65%). Bivariate and logistic regression analyses showed that age was the only variable independently associated with VCF (OR 1.12, 1.05 to 1.19). Conclusion: VCFs are not unusual in OBD patients. Radiologists and clinicians should specifically look for the presence of VCFs in patients with IBD, particularly the elderly, by using abdominal and pelvic CT scans.
  • Thumbnail Image
    Item
    ¿Es el uso de muñequera más efectivo que el uso de banda de antebrazo en la epicondilitis lateral?
    (2017) Meissner, Arturo; Vives, María Ignacia; Román Veas, Javier Andrés
  • Thumbnail Image
    Item
    Evaluación de la microcirculación con sidestream dark field (SDF) Microscan® como método de monitorización en microcirugía en modelo porcino
    (2016) Yáñez, Ricardo; Cifuentes, Ignacio; Rodríguez, José Ramón; Salisbury, Carolina; Dagnino, Bruno; Guerra Sánchez, Claudio Alejandro; Meissner, Arturo; Menchaca, Rodrigo; Hernández P., Glenn
  • Thumbnail Image
    Item
    Impairment of exogenous lactate clearance in experimental hyperdynamic septic shock is not related to total liver hypoperfusion
    (2014) Tapia Ossa, Pablo José; Soto, Dagoberto; Bruhn, Alejandro; Alegría, Leyla; Jarufe Cassis, Nicolás; Kattan Tala, Eduardo José; Regueira Heskia, Tomás; Meissner, Arturo; Menchaca, Rodrigo; Vives, María Ignacia
    Introduction: Although the prognostic value of persistent hyperlactatemia in septic shock is unequivocal, its physiological determinants are controversial. Particularly, the role of impaired hepatic clearance has been underestimated and is only considered relevant in patients with liver ischemia or cirrhosis. Our objectives were to establish whether endotoxemia impairs whole body net lactate clearance, and to explore a potential role for total liver hypoperfusion during the early phase of septic shock.Methods: After anesthesia, 12 sheep were subjected to hemodynamic/perfusion monitoring including hepatic and portal catheterization, and a hepatic ultrasound flow probe. After stabilization (point A), sheep were alternatively assigned to lipopolysaccharide (LPS) (5 mcg/kg bolus followed by 4 mcg/kg/h) or sham for a three-hour study period. After 60 minutes of shock, animals were fluid resuscitated to normalize mean arterial pressure. Repeated series of measurements were performed immediately after fluid resuscitation (point B), and one (point C) and two hours later (point D). Monitoring included systemic and regional hemodynamics, blood gases and lactate measurements, and ex-vivo hepatic mitochondrial respiration at point D. Parallel exogenous lactate and sorbitol clearances were performed at points B and D. Both groups included an intravenous bolus followed by serial blood sampling to draw a curve using the least squares method.Results: Significant hyperlactatemia was already present in LPS as compared to sham animals at point B (4.7 (3.1 to 6.7) versus 1.8 (1.5 to 3.7) mmol/L), increasing to 10.2 (7.8 to 12.3) mmol/L at point D. A significant increase in portal and hepatic lactate levels in LPS animals was also observed. No within-group difference in hepatic DO2, VO2 or O2 extraction, total hepatic blood flow (point D: 915 (773 to 1,046) versus 655 (593 to 1,175) ml/min), mitochondrial respiration, liver enzymes or sorbitol clearance was found. However, there was a highly significant decrease in lactate clearance in LPS animals (point B: 46 (30 to 180) versus 1,212 (743 to 2,116) ml/min, P <0.01; point D: 113 (65 to 322) versus 944 (363 to 1,235) ml/min, P <0.01).Conclusions: Endotoxemia induces an early and severe impairment in lactate clearance that is not related to total liver hypoperfusion.