Examinando por Autor "Santamarina, M."

Mostrando 1 - 3 de 3
  • Miniatura
    Ítem
    Sildenafil for treating patients with COVID-19 and perfusion mismatch: a pilot randomized trial
    (BioMed Central Ltd, 2022-01) Santamarina, M.; Beddings, I.; Lomakin, F.; Boisier Riscal, D.; Gutiérrez Claveria, M.; Vidal Marambio, J.; Retamal Báez, N.; Pavez Novoa, C.; Reyes Allende, C.; Ferreira Perey, P.; Gutiérrez Torres, M.; Villalobos Mazza, C.; Vergara Sagredo, C.; Ahumada Bermejo, S.; Labarca Mellado, E.; Barthel Munchmeyer, E.; Marchant Ramos, S.; Volpacchio, M.; Vega, J.
    Background: SARS-CoV-2 seems to affect the regulation of pulmonary perfusion. Hypoperfusion in areas of well-aerated lung parenchyma results in a ventilation–perfusion mismatch that can be characterized using subtraction computed tomography angiography (sCTA). This study aims to evaluate the efficacy of oral sildenafil in treating COVID-19 inpatients showing perfusion abnormalities in sCTA. Methods: Triple-blinded, randomized, placebo-controlled trial was conducted in Chile in a tertiary-care hospital able to provide on-site sCTA scans and ventilatory support when needed between August 2020 and March 2021. In total, 82 eligible adults were admitted to the ED with RT-PCR-confirmed or highly probable SARS-COV-2 infection and sCTA performed within 24 h of admission showing perfusion abnormalities in areas of well-aerated lung parenchyma; 42 were excluded and 40 participants were enrolled and randomized (1:1 ratio) once hospitalized. The active intervention group received sildenafil (25 mg orally three times a day for seven days), and the control group received identical placebo capsules in the same way. Primary outcomes were differences in oxygenation parameters measured daily during follow-up (PaO2/FiO2 ratio and A-a gradient). Secondary outcomes included admission to the ICU, requirement of non-invasive ventilation, invasive mechanical ventilation (IMV), and mortality rates. Analysis was performed on an intention-to-treat basis. Results: Totally, 40 participants were enrolled (20 in the placebo group and 20 in the sildenafil group); 33 [82.5%] were male; and median age was 57 [IQR 41–68] years. No significant differences in mean PaO2/FiO2 ratios and A-a gradients were found between groups (repeated-measures ANOVA p = 0.67 and p = 0.69). IMV was required in 4 patients who received placebo and none in the sildenafil arm (logrank p = 0.04). Patients in the sildenafil arm showed a significantly shorter median length of hospital stay than the placebo group (9 IQR 7–12 days vs. 12 IQR 9–21 days, p = 0.04). Conclusions: No statistically significant differences were found in the oxygenation parameters. Sildenafil treatment could have a potential therapeutic role regarding the need for IMV in COVID-19 patients with specific perfusion patterns in sCTA. A large-scale study is needed to confirm these results.
  • Miniatura
    Ítem
    Superior vena cava syndrome due to a leiomyosarcoma of the anterior mediastinum: a case report and literature overview
    (Elsevier Ltd, 2014) Labarca, E.; Zapico, A.; Ríos, B.; Martinez, F.; Santamarina, M.
    INTRODUCTION: Leiomyosarcomas are an infrequent cause of malignant superior vena cava syndrome (VCS). PRESENTATION OF CASE: A 51-year old male patient was admitted for a three-day history of dyspnoea, dysphagia and erythema of the head and neck. Computed tomography and magnetic resonance imaging showed a lesion arising on the anterior mediastinum, which was in close proximity with a thrombus in the superior vena cava. Surgical excision was performed, including open resection of the primary tumour and an atrio-innominate vein bypass with 8-mm polytetrafluoroethylene (PTFE). Histology confirmed a leiomyosarcoma and postoperative radiotherapy sessions were performed. Due to evidence of enlarge ment of the thrombus, a second intervention was undertaken. In this procedure, a remainder of the primary tumour was resected and the superior vena cava reconstructed with an autologous pericardium patch. The patient recovered satisfactorily and was discharged on the seventh postoperative day, with no evidence for relapse after 10 months of follow-up. DISCUSSION: Leiomyosarcomas comprise less than 2% of the tumours of the mediastinum and are a rare cause of paraneoplastic VCS. Male patients in their sixties are most commonly affected. Relapses seem to be common, and thus a careful follow-up is often recommended. CONCLUSION: In spite of the limited data on the management of thoracic leiomyosarcomas, surgery is currently considered the mainstay of treatment. © 2014 The Authors. Published by Elsevier Ltd. on behalf of Surgical Associates Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).
  • Miniatura
    Ítem
    Tríada de Carney. Una rara asociación de tumores infrecuentes. Caso clínico
    (Sociedad Médica de Santiago, 2017-04) Vega, J.; Navarro Subiabre, J.; Lovera Riquelme, C.; Opazo, H.; Santamarina, M.
    Carney described a disorder characterized by the presence of several uncommon tumors which were pulmonary chondromas, gastric sarcomas and extra-adrenal paragangliomas. We report a 14 year-old girl in whom multiple gastric tumors were discovered during a study of an iron deficiency anemia and was subjected to a partial gastrectomy. At 25 years of age, she developed several pulmonary chondromas and at 33 years, a mediastinal tumor with features of an extra-adrenal paraganglioma was found. At 35 years of age, a total gastrectomy was performed to remove a gastrointestinal stromal tumor with excision of peritoneal and lymph node metastasis. One year later, the patient died due to liver failure secondary to liver metastases.