Browsing by Author "Ulloa, Rodrigo"

Now showing 1 - 5 of 5
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    Coexistence of a fuid responsive state and venous congestion signals in critically ill patients: a multicenter observational proof-of-concept study
    (2024) Muñoz, Felipe; Born, Pablo; Bruna, Mario; Ulloa, Rodrigo; Gonzalez Almonacid, Cecilia Ignacia; Philp Sandoval, Valerie Rose; Mondaca Pavie, Roberto Francisco     ; Blanco Guerrero, Juan Pablo; Valenzuela Espinoza, Emilio Daniel; Retamal Montes, Jaime; Miralles, Francisco; Wendel-Garcia, Pedro D.; Ospina-Tascón, Gustavo A.; Castro Lopez, Ricardo Adolfo; Rola, Philippe; Bakker, Jan; Hernández P., Glenn; Kattan Tala, Eduardo José
    Background: Current recommendations support guiding fluid resuscitation through the assessment of fluid responsiveness. Recently, the concept of fluid tolerance and the prevention of venous congestion (VC) have emerged as relevant aspects to be considered to avoid potentially deleterious side effects of fluid resuscitation. However, there is paucity of data on the relationship of fluid responsiveness and VC. This study aims to compare the prevalence of venous congestion in fluid responsive and fluid unresponsive critically ill patients after intensive care (ICU) admission. Methods: Multicenter, prospective cross-sectional observational study conducted in three medical–surgical ICUs in Chile. Consecutive mechanically ventilated patients that required vasopressors and admitted < 24 h to ICU were included between November 2022 and June 2023. Patients were assessed simultaneously for fluid responsiveness and VC at a single timepoint. Fluid responsiveness status, VC signals such as central venous pressure, estimation of left ventricular filling pressures, lung, and abdominal ultrasound congestion indexes and relevant clinical data were collected. Results: Ninety patients were included. Median age was 63 [45–71] years old, and median SOFA score was 9 [7–11]. Thirty-eight percent of the patients were fluid responsive (FR+), while 62% were fluid unresponsive (FR−). The most prevalent diagnosis was sepsis (41%) followed by respiratory failure (22%). The prevalence of at least one VC signal was not significantly different between FR+ and FR− groups (53% vs. 57%, p = 0.69), as well as the proportion of patients with 2 or 3 VC signals (15% vs. 21%, p = 0.4). We found no association between fluid balance, CRT status, or diagnostic group and the presence of VC signals. Conclusions: Venous congestion signals were prevalent in both fluid responsive and unresponsive critically ill patients. The presence of venous congestion was not associated with fluid balance or diagnostic group. Further studies should assess the clinical relevance of these results and their potential impact on resuscitation and monitoring practices.
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    Creencias y conocimiento matemático escolar al comienzo de la formación inicial docente en estudiantes de Pedagogía General Básica
    (2019) Martínez Videla, Maria Victoria; Rojas Sateler, Francisco; Ulloa, Rodrigo; Chandía, Eugenio; Ortíz, Andres; Perdomo Díaz, Josefa
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    Exploring the relationship between capillary refill time, skin blood flow and microcirculatory reactivity during early resuscitation of patients with septic shock: a pilot study
    (2023) Contreras, Roberto; Hernandez, Glenn; Daniel Valenzuela, Emilio; Gonzalez, Cecilia; Ulloa, Rodrigo; Soto, Dagoberto; Castro, Ricardo; Guzman, Camila; Oviedo, Vanessa; Alegria, Leyla; Vidal, Diego; Morales, Sebastian; Adolfo Ospina-Tascon, Gustavo; Bakker, Jan; Kattan, Eduardo
    Capillary refill time (CRT), a costless and widely available tool, has emerged as a promising target to guide septic shock resuscitation. However, it has yet to gain universal acceptance due to its potential inter-observer variability. Standardization of CRT assessment may minimize this problem, but few studies have compared this approach with techniques that directly assess skin blood flow (SBF). Our objective was to determine if an abnormal CRT is associated with impaired SBF and microvascular reactivity in early septic shock patients. Twelve septic shock patients were subjected to multimodal perfusion and hemodynamic monitoring for 24 h. Three time-points (0, 1, and 24 h) were registered for each patient. SBF was measured by laser doppler. We performed a baseline SBF measurement and two microvascular reactivity tests: one with a thermal challenge at 44 & DEG;C and other with a vascular occlusion test. Ten healthy volunteers were evaluated to obtain reference values. The patients (median age 70 years) exhibited a 28-day mortality of 50%. Baseline CRT was 3.3 [2.7-7.3] seconds. In pooled data analysis, abnormal CRT presented a significantly lower SBF when compared to normal CRT [44 (13.3-80.3) vs 193.2 (99.4-285) APU, p = 0.0001]. CRT was strongly associated with SBF (R-2 0.76, p < 0.0001). An abnormal CRT also was associated with impaired thermal challenge and vascular occlusion tests. Abnormal CRT values observed during early septic shock resuscitation are associated with impaired skin blood flow, and abnormal skin microvascular reactivity. Future studies should confirm these results.
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    Optimization Under Uncertainty in Sustainable Agriculture and Agrifood Industry
    (Springer Cham, 2024) Garafulic, Max; Mac Cawley, Alejandro F.; Péra, Thiago Guilherme; João, Abner Matheus; Caixeta Filho, José Vicente; Hampel, David; Tláskal, Martin; Janová, Jitka; Pires Ribeiro, João; Cruz, Lourenço; Barbosa Póvoa, Ana; Peinado Guerrero, Miguel; Ahumada, Omar; Ulloa, Rodrigo; Hernández Cruz, Xaimarie; Neal, Grace; Jayani, Abhay; Villalobos, J. Rene; Oliveira, Anderson; Firmino, Fabricio; Vieira Cruz, Pedro; Oliveira Sampaio, Jonice de; Serra da Cruz, Sérgio Manuel; Albornoz, Víctor M.; Zamora, Gabriel E.; Soto Silva, Wladimir E.; González Araya, Marcela C.; PlàAragonés, Lluís M.; Albornoz, Víctor M.; Mac Cawley, Alejandro; Plà-Aragonés, Lluis M.
    This book explores optimization under uncertainty and related applications in agriculture, sustainable supply chains and the agrifood industry. Rapid changes in the primary sector are leading to more and more industrialized structures, which require optimization methods in order to cope with today’s challenges. Addressing uncertainty in the agrifood industry may lead to more robust supply chain designs or to diversified risk. Sustainability requires interaction with the environmental or social sciences. This book bridges the gap between optimization theory, uncertainty, sustainability and primary-sector applications (mainly in the agriculture and food industry, but also fisheries, forestry and natural resources in general). Although it has been a major challenge for the operations research community, this urgently needed interdisciplinary collaboration is not adequately covered in most current curricula in applied mathematics, economics or (agronomic/industrial/forest) engineering. This book highlights research that can help fill this gap. The individual chapters cover applications of stochastic integer linear programming and multicriteria decision methods in agriculture. The topics addressed include uncertainty in areas such as the sugar cane industry, pig farming, and cold storage for perishable products. Large-scale sustainable food production is a growing concern; this book offers solutions to help meet global demand in agriculture by using and improving the methods of optimization theory and operations research.