Browsing by Author "Ulloa Morrison, Rodrigo"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Dynamic changes of hepatic vein Doppler velocities predict preload responsiveness in mechanically ventilated critically ill patients
    (2024) Bruna, Mario; Alfaro, Sebastián; Muñoz Ferrada, Felipe Ignacio; Cisternas, Liliana; González, Cecilia; Conlledo, Rodrigo; Ulloa Morrison, Rodrigo; Huilcaman, Marcos; Retamal, Jaime; Castro López, Ricardo; Rola, Philippe; Wong, Adrian; Argaiz, Eduardo R.; Contreras, Roberto; Hernández P., Glenn; Kattan Tala, Eduardo José
    Background: Assessment of dynamic parameters to guide fluid administration is one of the mainstays of current resuscitation strategies. Each test has its own limitations, but passive leg raising (PLR) has emerged as one of the most versatile preload responsiveness tests. However, it requires real-time cardiac output (CO) measurement either through advanced monitoring devices, which are not routinely available, or echocardiography, which is not always feasible. Analysis of the hepatic vein Doppler waveform change, a simpler ultrasound-based assessment, during a dynamic test such as PLR could be useful in predicting preload responsiveness. The objective of this study was to assess the diagnostic accuracy of hepatic vein Doppler S and D-wave velocities during PLR as a predictor of preload responsiveness. Methods: Prospective observational study conducted in two medical–surgical ICUs in Chile. Patients in circulatory failure and connected to controlled mechanical ventilation were included from August to December 2023. A baseline ultrasound assessment of cardiac function was performed. Then, simultaneously, ultrasound measurements of hepatic vein Doppler S and D waves and cardiac output by continuous pulse contour analysis device were performed during a PLR maneuver. Results: Thirty-seven patients were analyzed. 63% of the patients were preload responsive defined by a 10% increase in CO after passive leg raising. A 20% increase in the maximum S wave velocity after PLR showed the best diagnostic accuracy with a sensitivity of 69.6% (49.1–84.4) and specificity of 92.8 (68.5–99.6) to detect preload responsiveness, with an area under curve of receiving operator characteristic (AUC–ROC) of 0.82 ± 0.07 (p = 0.001 vs. AUC–ROC of 0.5). D-wave velocities showed worse diagnostic accuracy. Conclusions: Hepatic vein Doppler assessment emerges as a novel complementary technique with adequate predictive capacity to identify preload responsiveness in patients in mechanical ventilation and circulatory failure. This technique could become valuable in scenarios of basic hemodynamic monitoring and when echocardiography is not feasible. Future studies should confirm these results.
  • Thumbnail Image
    Item
    Effect of decreasing respiratory rate on the mechanical power of ventilation and lung injury biomarkers: a randomized cross-over clinical study in COVID-19 ARDS patients
    (Springer Nature, 2025) Damiani Rebolledo, L. Felipe; Basoalto Escobar, Roque Ignacio; Oviedo Álvarez, Vanessa Andrea; Alegría Vargas, Leyla; Soto Muñoz, Dagoberto Igor; Bachmann Barrón, María Consuelo; Jalil Contreras, Yorschua Frederick; Santis Fuentes, César Antonio; Carpio Cordero, David Bernardo; Ulloa Morrison, Rodrigo; Valenzuela Espinoza, Emilio Daniel; Vera Alarcón, María Magdalena; Schultz, Marcus J.; Retamal Montes, Jaime; Bruhn, Alejandro; Bugedo Tarraza, Guillermo
    Background The respiratory rate (RR) is a key determinant of the mechanical power of ventilation (MP). The effect of reducing the RR on MP and its potential to mitigate ventilator-induced lung injury remains unclear. Objectives To compare invasive ventilation using a lower versus a higher RR with respect to MP and plasma biomarkers of lung injury in COVID-19 ARDS patients. Methods In a randomized cross-over clinical study in COVID-19 ARDS patients, we compared ventilation using a lower versus a higher RR in time blocks of 12 h. Patients were ventilated with tidal volumes of 6 ml/kg predicted body weight, and positive-end-expiratory pressure and fraction of inspired oxygen according to an ARDS network table. Respiratory mechanics and hemodynamics were assessed at the end of each period, and blood samples were drawn for measurements of inflammatory cytokines, epithelial and endothelial lung injury markers. In a subgroup of patients, we performed echocardiography and esophageal pressure measurements. Results We enrolled a total of 32 patients (26 males [81%], aged 52 [44–64] years). The median respiratory rate during ventilation with a lower and a higher RR was 20 [16–22] vs. 30 [26–32] breaths/min (p < 0.001), associated with a lower median minute ventilation (7.3 [6.5–8.5] vs. 11.6 [10–13] L/min [p < 0.001]) and a lower median MP (15 [11–18] vs. 25 [21–32] J/min [p < 0.001]). No differences were observed in any inflammatory (IL-6, IL-8, and TNF-R1), epithelial (s-RAGE and SP-D), endothelial (Angiopoietin-2), or pro-fibrotic activity (TGF-ß) marker between high or low RR. Cardiac function by echocardiography, and respiratory mechanics using esophageal pressure measurements were also not different. Conclusions Reducing the respiratory rate decreases mechanical power in COVID-19 ARDS patients but does not reduce plasma lung injury biomarkers levels in this cross-over study. Study registration This study is registered at clinicaltrials.gov (study identifier NCT04641897)
  • No Thumbnail Available
    Item
    Long-term mortality of coronavirus disease 2019 critically ill patients that required percutaneous tracheostomy in Chile: A multicenter cohort study
    (Wolters Kluwer Health, Inc., 2024) Ulloa Morrison, Rodrigo; Escalona, José; Navarrete, Pablo; Espinoza, Javiera; Bravo Morales, Sebastián Ignacio; Pastore Thomson, Antonia; Reyes, Sebastián; Bozinovic, Milan; Abbott, Francisco; Pairumani, Ronald; Noguera, Roselyn; Vera Alarcón, María Magdalena; González, Felipe; Valle, Felipe; Bakker, Jan; Bugedo Tarraza, Guillermo; Kattan Tala, Eduardo José
    Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leads to mechanical ventilation (MV) in approximately 20% of hospitalized patients. Tracheostomy expedites weaning of respiratory support. Moreover, there is a paucity of data regarding long-term outcomes of tracheostomized coronavirus disease 2019 (COVID-19) patients. The objective of this study was to describe 1-year mortality in a cohort of COVID-19 critically ill patients who required percutaneous tracheostomy in Chile and to assess the impact of age on outcomes. Methods: A multicenter prospective observational study was conducted in 4 hospitals in Chile between March 2020 and July 2021. Patients with confirmed SARS-CoV-2 infection connected to MV and required percutaneous tracheostomy were included. Baseline data, relevant perioperative and long-term outcomes, such as 1-year mortality, MV duration, intensive care unit (ICU), and hospital length of stay were registered. Patients were dichotomized according to age group (< and ≥ 70 years). Univariate and multivariate logistic regressions were performed to identify predictors of 1-year mortality. Results: Of 1319 COVID-19 ventilated critically ill patients, 23% (304) required a percutaneous tracheostomy. One-year mortality of the study group was 25% (20.2%-30.3%). ICU and hospital length of stay (LOS) were of 37 (27-49) and 52 (40-72) days. One-year mortality was higher in patients ≥ 70 years (36.9% vs. 21.2%, P = 0.012). Multivariate analysis confirmed age and baseline sequential organ failure assessment (SOFA) score as independent predictors, while time from intubation to tracheostomy was not. Conclusion: In COVID-19 critically ill patients who required percutaneous tracheostomy in Chile, the 1-year mortality rate was 25%, with a relevant impact of age on outcomes. An appropriate patient selection likely accounted for the low mortality rate. Future studies should confirm these results.