Efeito crônico do pré-condicionamento isquêmico na função vascular: revisão sistemática

Introdução: O pré-condicionamento isquêmico (PCI) tem demostrado efeito protetor aos tecidos contra danos isquêmicos subsequentes, já que aparenta estar relacionado aos mecanismos vasodilatadores vasculares. Sabe-se que uma sessão aguda de PCI traz efeitos vasodilatadores endotélio dependente. Objetivo: Revisar sistematicamente o efeito crônico da realização do PCI sobre a função vascular. Métodos: Foi realizada pesquisa bibliográfica nas bases de dados eletrônicas Medline, Cochrane, Embase, Lilacs, SciElo, Web of Science e Scopus, sendo considerados ensaios clínicos controlados publicados até fevereiro de 2022. As buscas foram realizadas utilizando os descritores: Ischemic preconditioning; Preconditioning, Ischemic; Ischemic Pre-Conditioning; Ischemic Pre Conditioning; Pre-Conditioning, Ischemic; regional blood flow; Vascular Endothelium; Vasodilatation; Endothelium, vascular. Os artigos incluídos após análise de elegibilidade tiveram sua qualidade metodológica avaliada por meio da escala de classificação Downs and Black. Resultados: Foram encontrados 622 artigos dos quais apenas 11 preencheram os critérios de elegibilidade. Os 11 artigos possuíam uma população heterogênea composta por jovens saudáveis, pessoas com diagnóstico de diabetes Mellitus, doença arterial coronariana, hipertensão arterial sistêmica e acidente vascular encefálico, além de tabagistas. Foi demonstrado melhora da função vascular após a aplicação do protocolo de PCI de forma crônica. Adicionalmente, cinco desses artigos demostraram a melhora da função vascular por via dependente do endotélio, três por via endotélio independente e outros três estudos melhora tanto de forma dependente quanto independente. Conclusão: O PCI aplicado de forma crônica parece melhorar a função vascular, tanto por via endotélio dependente como independente

Respostas hemodinâmicas durante exercício muscular inspiratório em jovens saudáveis

The literature on hemodynamic responses during inspiratory muscle exercise (IME) lacks a consensus. To evaluate and compare hemodynamic responses during an IME session with and without resistive load, 15 sedentary men were subjected to two randomized IME sessions: one with 40% of maximal inspiratory pressure (IME 40%) and another without a resistive load (Sham), both of which were performed for two minutes over eight sets with oneminute intervals. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), total peripheral resistance (TPR), stroke volume (SV), cardiac output (CO), and heart rate (HR) were measured by infrared digital photoplethysmography during five basal minutes and during the IME sessions. One-way ANOVA analysis of variance and the Student’s t test for paired data were used to analyze hemodynamic response and delta values between sessions, respectively. Effect size was evaluated by Cohen’s D. A 5% significance level was adopted. SBP responses (sham: ∆−1±2 vs. 40%: ∆−4±2mmHg, p=0.27), DBP (sham: ∆2±1 vs. 40%: ∆1±2mmHg, p=0.60) and MBP (sham: ∆2±1 vs. 40%: ∆0±2mmHg, p=0.28) were similar between sessions. HR increases were higher in the 40% IME session than in the sham session (sham: ∆9±2 vs. 40%: ∆3±2bpm, p=0.001). SV only decreased during the sham session but responses were similar between sessions (sham: ∆−2±2 vs. IME 40%: ∆−6±2ml, p=0.13). Both sessions did not change SBP, DBP, MBP, CO, and TPR, but we observed a greater increase in HR in the IME 40% session. Only the Sham session decreased SV.A literatura carece de um consenso sobre respostas hemodinâmicas durante o exercício muscular  inspiratório (EMI). Este estudo buscou avaliar e comparar as respostas hemodinâmicas durante uma sessão de EMI com e sem carga resistiva. Para tanto, 15 homens sedentários foram submetidos a duas sessõesrandomizadas de EMI: 40% da pressão inspiratória máxima (EMI 40%) e sem carga resistiva (sham), realizadas por dois minutos em oito séries e com intervalos de um minuto. A pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), pressão arterial média (PAM), resistência periférica total (RPT), volume sistólico (VS), débito cardíaco (DC) e frequência cardíaca (FC) foram medidos por fotopletismografia  infravermelha digital por cinco minutos basais e durante as sessões de EMI. Anova de um fator e o teste t de Student para dados pareados foram usados para analisar a resposta hemodinâmica e os valores delta entre as sessões, respectivamente. O tamanho do efeito foi avaliado pelo d de Cohen. Adotou-se nível de significância de 5%. As respostas de PAS (sham: ∆−1±2 vs. 40%: ∆−4±2mmHg, p=0,27), PAD (sham: ∆2±1 vs. 40%: ∆1±2mmHg, p=0,60) e PAM (sham: ∆2±1 vs. 40%:∆0±2mmHg, p=0,28) foram semelhantes entre as sessões. Os aumentos da FC foram maiores na sessão de EMI 40% do que nas sessões sham (sham: ∆9±2 vs. 40%: ∆3±2bpm, p=0,001). O VS diminuiu exclusivamente durante a sessão sham mas a resposta foi semelhante entre as sessões (sham: ∆−2±2 vs. EMI 40%: ∆−6±2ml, p=0,13). Ambas as sessões não causaram alteração nas variáveis PAS, PAD, PAM, DC e RPT, mas notamos um aumento maior da FC na sessão EMI 40%. Apenas a sessão sham reduziu o VS.No hay consenso en la literatura sobre las respuestas hemodinámicas durante el ejercicio muscular inspiratorio (EMI).El objetivo de este estudio fue evaluar y comparar las respuestas hemodinámicas durante una sesión de EMI con y sin carga resistiva. Para ello, quince hombres sedentarios recibieron dos sesiones aleatorias de EMI: el 40% de la presión inspiratoria máxima (EMI40%) y sin carga resistiva (sham), realizadas durante dos minutos, ocho sesiones y a intervalos de un minuto. La presión arterialsistólica (PAS), la presión arterial diastólica (PAD), la presión arterial media (PAM), la resistencia periférica total (RPT), el volumensistólico (VS), el gasto cardíaco (GC) y la frecuencia cardíaca (FC) se midieron mediante fotopletismografía infrarroja digital durantecinco minutos al inicio y durante las sesiones de EMI. Se utilizaron ANOVA unidireccional y la prueba t de Student a datos emparejadospara analizar la respuesta hemodinámica y los valores delta entre las sesiones. El tamaño del efecto se evaluó por el d de Cohen. Elnivel de significancia adoptado fue de 5%. Las respuestas de PAS (sham: Δ−1±2 vs. 40%: ∆−4±2mmHg, p=0,27), PAD (sham: ∆2±1 vs.40%: ∆1±2mmHg, p=0,60) y PAM (sham: ∆2±1 vs. 40%: ∆0±2mmHg,p=0,28) fueron similares entre las sesiones. El incremento de la FC fue mayor en la sesión de EMI 40% comparada con la sesión sham (sham: Δ9±2 vs. 40%: ∆3±2bpm, p=0,001). El VS tuvo una disminución exclusiva durante la sesión sham, pero la respuestafue similar entre las sesiones (sham: Δ−2±2 vs. EMI 40%: ∆−6±2ml, p=0,13). Ambas sesiones no tuvieron cambios en las variables PAS, PAD, PAM, DC y RPT, pero se observó un mayor incremento de la FC en la sesión EMI 40%. Solamente en la sesión sham hubo una reducción del V

Hemodynamic responses during inspiratory muscle exercise in healthy young adults

ABSTRACT The literature on hemodynamic responses during inspiratory muscle exercise (IME) lacks a consensus. To evaluate and compare hemodynamic responses during an IME session with and without resistive load, 15 sedentary men were subjected to two randomized IME sessions: one with 40% of maximal inspiratory pressure (IME 40%) and another without a resistive load (Sham), both of which were performed for two minutes over eight sessions with one-minute intervals. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), total peripheral resistance (TPR), stroke volume (SV), cardiac output (CO), and heart rate (HR) were measured by infrared digital photoplethysmography during five basal minutes and during the IME sessions. One-way analysis of variance and the Student’s t test for paired data were used to analyze hemodynamic response and delta values between sessions. Effect size was evaluated by Cohen’s D. A 5% significance level was adopted. SBP responses (sham: ∆−1±2 vs. 40%: ∆−4±2mmHg, p=0.27), DBP (sham: ∆2±1 vs. 40%: ∆1±2mmHg, p=0.60) and MBP (sham: ∆2±1 vs. 40%: ∆0±2mmHg, p=0.28) were similar between sessions. HR increases were higher in the 40% IME session than in the sham session (sham: ∆9±2 vs. 40%: ∆3±2bpm, p=0.001). SV only decreased during the sham session but responses were similar between sessions (sham: ∆−2±2 vs. IME 40%: ∆−6±2ml, p=0.13). Both sessions did not change SBP, DBP, MBP, CO, and TPR, but we observed a greater increase in HR in the IME 40% session. Only the Sham session decreased SV

Influência da hereditariedade para hipertensão arterial na hipotensão pós-exercício

Verificar o comportamento cardiovascular de homens normotensos com histórico familiar positivo para hipertensão arterial proveniente da mãe e de homens normotensos com histórico familiar proveniente do pai após uma sessão de exercício aeróbio. Foram selecionados 35 homens adultos divididos nos grupos: HF+mãe (somente mãe com hipertensão arterial, n=14) e HF+pai (somente pai com hipertensão arterial, n=21). Os participantes foram submetidos ao exercício aeróbio, em cicloergômetro (Kikos®), por 50 minutos, em intensidade de 50 a 70% da frequência cardíaca de reserva (sessão exercício) e a uma sessão controle. As variáveis pressão arterial média (FinometerPro®) e fluxo sanguíneo do antebraço (Pletismografia de Oclusão Venosa-Hokanson®) foram registradas continuamente durante 10 minutos pré e 30 minutos pós cada sessão. A resistência vascular do antebraço foi calculada pela divisão da pressão arterial média pelo fluxo sanguíneo do antebraço. Foi considerado p≤0,05 como diferença significativa. No grupo HF+mãe a pressão arterial média e a resistência vascular do antebraço não modificaram significativamente no momento pós em relação ao momento pré-exercício. Diferentemente, no grupo HF+pai a pressão arterial média e resistência vascular do antebraço reduziram significativamente na recuperação do exercício. Na sessão controle essas variáveis aumentaram significativamente no pós em relação ao pré, em ambos os grupos. O exercício físico não provocou modificações no sistema cardiovascular de homens normotensos, com histórico familiar positivo para hipertensão proveniente da mãe. Enquanto aqueles com histórico familiar positivo para hipertensão proveniente do pai apresentaram hipotensão pós-exercício, comportamento parcialmente justificado pela diminuição da resistência vascular do antebraço.To verify the cardiovascular response of normotensive men with positive family history of arterial hypertension from the mother and of normotensive men with positive family history of arterial hypertension from the father after an aerobic exercise session. Were selected 35 adult men divided into groups: HF+mother (only mother with arterial hypertension, n = 14) and HF+father (only father with arterial hypertension, n = 21). The participants underwent aerobic exercise, on a cycle ergometer (Kikos®), for 50 minutes, at intensity of 50 to 70% of the reserve heart rate (exercise session) and a control session. The variables mean arterial pressure (FinometerPro®) and forearm blood flow (Venous Occlusion Plethysmography-Hokanson®) were continuously recorded for 10 minutes before and 30 minutes after each session. The forearm vascular resistance was calculated by dividing the mean arterial pressure by the forearm blood flow. Was considered significant p≤0.05. In the HF+mother group, mean arterial pressure and forearm vascular resistance did not change significantly in the post-moment compared to the pre-exercise moment. In contrast, in the HF+father group, mean arterial pressure and forearm vascular resistance significantly reduced in recovery from exercise. In the control session, these variables increased significantly in the post compared to the pre, in both groups. Physical exercise did not cause changes in the cardiovascular system of normotensive men, with a positive family history of hypertension from the mother. While those with a positive family history of hypertension from their father presented post-exercise hypotension, behavior partially justified by the decrease in vascular resistance in the forearm

Diagnostic methods to assess inspiratory and expiratory muscle strength

Impairment of (inspiratory and expiratory) respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not widely known and available. There are various methods of assessing respiratory muscle strength during the inspiratory and expiratory phases. These methods are divided into two categories: volitional tests (which require patient understanding and cooperation); and non-volitional tests. Volitional tests, such as those that measure maximal inspiratory and expiratory pressures, are the most commonly used because they are readily available. Non-volitional tests depend on magnetic stimulation of the phrenic nerve accompanied by the measurement of inspiratory mouth pressure, inspiratory esophageal pressure, or inspiratory transdiaphragmatic pressure. Another method that has come to be widely used is ultrasound imaging of the diaphragm. We believe that pulmonologists involved in the care of patients with respiratory diseases should be familiar with the tests used in order to assess respiratory muscle function.Therefore, the aim of the present article is to describe the advantages, disadvantages, procedures, and clinical applicability of the main tests used in the assessment of respiratory muscle strength

Diagnostic methods to assess inspiratory and expiratory muscle strength

Impairment of (inspiratory and expiratory) respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not widely known and available. There are various methods of assessing respiratory muscle strength during the inspiratory and expiratory phases. These methods are divided into two categories: volitional tests (which require patient understanding and cooperation); and non-volitional tests. Volitional tests, such as those that measure maximal inspiratory and expiratory pressures, are the most commonly used because they are readily available. Non-volitional tests depend on magnetic stimulation of the phrenic nerve accompanied by the measurement of inspiratory mouth pressure, inspiratory esophageal pressure, or inspiratory transdiaphragmatic pressure. Another method that has come to be widely used is ultrasound imaging of the diaphragm. We believe that pulmonologists involved in the care of patients with respiratory diseases should be familiar with the tests used in order to assess respiratory muscle function.Therefore, the aim of the present article is to describe the advantages, disadvantages, procedures, and clinical applicability of the main tests used in the assessment of respiratory muscle strength