Effects of negative inclination of the head on intracranial pressure and cardiovascular control in healthy individuals: perspectives for spatial travels

• Grant number: 19/25569-2
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2020
• End date: February 28, 2023
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Thiago Luiz de Russo
• Grantee: Thiago Luiz de Russo
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated researchers: Aparecida Maria Catai ; Emiliano Santarnecchi ; Gustavo Henrique Frigieri Vilela
• Associated scholarship(s): 22/04974-9 - Effects of negative inclination of the head on intracranial pressure and cardiovascular control in healthy individuals: perspectives for spacial travels, BP.TT; 20/13708-5 - Effects of negative inclination of the head on intracranial pressure and cardiovascular control in healthy individuals: perspectives for spacial travels, BP.TT

Abstract

Increased intracranial pressure (ICP) in microgravity environment may reduce brain compliance and impair compensatory brain mechanisms, causing decreased cerebral blood flow (CBF). Thus, brain functions may be affected, making this phenomenon worrisome to astronauts, especially in interplanetary and long-duration missions. The ICP elevation is usually due to fluid displacement from the lower limbs and trunk to the head. Changes in hemodynamic control can also be observed as increased sympathetic autonomic nervous system activity, perpetuating this cycle of elevated ICP and decreased brain functions. The gold standard for measuring ICP is an invasive method, but this method has important disadvantages, and therefore, non-invasive measurement devices have been developed and studied. Objective: to investigate hemodynamic effects in a microgravity model (head-down tilt); characterize the immediate changes in the ICP waveform morphology during and after the test; to relate these changes to the autonomic nervous system behavior through the evaluation of heart rate variability (HRV) and baroreflex sensitivity (BRS). Methodology: a cross-sectional study with 50 healthy and active individuals, determined by biochemical tests, questionnaires, body composition, clinical examination and cardiopulmonary exercise test (CPET). Five meetings will be held: the first to clarify the nature of the project, to complete the sociodemographic questionnaire and the consent term. In the second one, a blood test will be done, and on the third day, the dual-energy X-ray absorptiometry (DXA) and CPET will be done. On the other days, the ICP and ANS function will be evaluated by the HRV and BRS before, during and after the head-down tilt test, which will consist of the subject inclination on the tilt table by -6 ° and -15 °. Statistics: Tests of normality (Kolmogorov-Smirnov) and homogeneity (Levene) will be applied. To verify the relationship between the postures and the ICP and cardiovascular variables, the ANOVA tests of repeated measures or Friedman will be performed, for parametric or non-parametric cases, respectively. For all analyzes, will be considered a significance level of 5% and a confidence interval of 95%. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GARCIA OLIVEIRA, SIMONE; LOURENCO NOGUEIRA, SAMUEL; ALEX MATOS RIBEIRO, JEAN; CARNAZ, LETICIA; REGINA ROCHA URRUCHIA, VITORIA; ALCANTARA, CAROLINA CARMONA; RUSSO, THIAGO L.. oncurrent validity and reliability of an activity monitoring for rehabilitation (AMoR) platform for step counting and sitting/lying time in post-stroke individual. Topics in Stroke Rehabilitation, v. 29, n. 2, FEB 2021. (13/25805-1, 17/13655-6, 19/25569-2)

GARCIA OLIVEIRA, SIMONE; LOURENCO NOGUEIRA, SAMUEL; ALEX MATOS RIBEIRO, JEAN; CARNAZ, LETICIA; REGINA ROCHA URRUCHIA, VITORIA; ALCANTARA, CAROLINA CARMONA; RUSSO, THIAGO L.. Concurrent validity and reliability of an activity monitoring for rehabilitation (AMoR) platform for step counting and sitting/lying time in post-stroke individuals. Topics in Stroke Rehabilitation, v. 29, n. 2, p. 11-pg., 2021-02-21. (19/25569-2, 13/25805-1, 17/13655-6)