Computational analysis for the diagnosis of organ dysfunction in Sepsis based on microcirculatory hemodynamics

• Grant number: 20/01034-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: May 01, 2020
• End date: August 31, 2022
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Ivan Hong Jun Koh
• Grantee: Carolina Toledo Ferraz
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated research grant: 17/21052-0 - Sepsis: mechanisms, therapeutic targets and epidemiology, AP.TEM

Abstract

The host reaction in Sepsis triggers complex pathophysiology that results in progressive organ dysfunction and is closely related to hemodynamic dysfunction, especially in the microvessel territory that directly interacts with cells of all organs and tissues. (Spronk et al, 2004; Vincent et al, 2005; Ait-Oufella et al, 2015; Ratiani et al, 2015). However, technological limitations to evaluate this territory of microscopic dimensions have restricted the progression in the acquisition of physiological and pathological knowledge of microcirculation to assist in the diagnosis, prognosis, and monitoring of the effectiveness of therapeutic processes. The rationale for therapy guided by macro hemodynamic parameters to date is fundamentally due to the difficulty of monitoring the microcirculatory dysfunction of septic patients, the absence of diagnostic classification of the stages of microcirculatory dysfunction. (Koh et al, 2010). Microcirculation analysis software (Microcirculation Analysis System (MAS), coupled with Sidestream Dark Field Imaging (SDF) in-vivo microcirculation capture is the main instrument today and has been used in the sublingual region of septic patients, mainly in European ICUs, in order to diagnose the stage of microcirculatory dysfunction in the different stages of Sepsis with and without septic shock (De Backer et al, 2002; Spronk et al, 2004). Despite the worldwide attempts, the benefit of its use is questioned by the methodological limitation for the analysis/interpretation of the captured images and also by the uncertainty that the sublingual region microcirculation may reflect the state of microcirculatory dysfunction of commonly compromised abdominal organs in Sepsis. Our previous research has shown that "graph analysis computer software", especially "Scattering Transform" has been able to distinguish the abnormal pattern of microcirculation between early and severe phases of Sepsis, a big step toward diagnostic-based analysis in microcirculatory dysfunction. (Ph.D., Jihan Mohamad Zoghbi, Defense 2016). However, the differentiation of disease progression between the most severe stages of the disease could not yet be discriminated, showing that the continuity of the computational study should concentrate efforts to identify and measure the sequence of changes in Sepsis progression from a stage of severe microcirculatory dysfunction. In addition, the present study intends to add a new diagnostic process of microcirculatory dysfunction by the infrared thermography method. By means of a thermal sensitivity (Flir) camera of high thermal sensitivity, with thermal differentiation up to 0.03°C, it is intended to map the thermal variation of organs and tissues and correlate with the state of micro, regional and macro hemodynamic alterations, in the attempt to verify the congruence and potential of its applicability as a method of rapid and early diagnosis of hemodynamic dysfunctions in Sepsis. (Ammer, 2004). Infrared thermography has been used in the clinic, mainly for diagnostic localization of inflamed tissues and we believe that the progressive reduction of microcirculatory dysfunction in Sepsis may be related to the reduction of tissue/organ-specific temperature, independent of macrocirculation and body temperature. (Allen et al, 2006; Ammer et al, 2009; E. Ring & Ammer, 2012). (AU)