Search results for "HEART RATE"

Resting sympatho-vagal balance is related to 10 km running performance in master endurance athletes

2018

Relationships between heart rate recovery after exercise (HRR, baseline heart rate variability measures (HRV), and time to perform a 10Km running trial (t10Km) were evaluated in "master" athletes of endurance to assess whether the measured indexes may be useful for monitoring the training status of the athletes. Ten “master” athletes of endurance, aged 40-60 years, were recruited. After baseline measures of HRV, the athletes performed a graded maximal test on treadmill and HRR was measured at 1 and 2 minutes from recovery. Subsequently they performed a 10Km running trial and t10Km was related to HRV and HRR indexes. The time to perform a 10Km running trial was significantly correlated with …

Heart rate variability as predictor of mortality in sepsis: A systematic review.

2018

Background Autonomic dysregulation is one of the recognized pathophysiological mechanisms in sepsis, generating the hypothesis that heart rate variability (HRV) can be used to predict mortality in sepsis. Methods This was a systematic review of studies evaluating HRV as a predictor of death in patients with sepsis. The search was performed by independent researchers in PubMed, LILACS and Cochrane, including papers in English, Portuguese or Spanish, indexed until August 20th, 2017 with at least 10 patients. Study quality was assessed by Newcastle-Ottawa Scale. To analyze the results, we divided the articles between those who measured HRV for short-term recordings ( 1 hour), and those who did…

Heart Rate Variability and Other Autonomic Markers in Children and Adolescents

2019

Cardiac Autonomic Activity during Sleep under the Influence of Radiofrequency Electromagnetic Fields. Autonome Herzaktivitat im Schlaf unter dem Einf…

2005

Question of the study We investigated the influence of radiofrequency electromagnetic fields emitted by digital mobile telephones on heart rate variability (HRV) during sleep in healthy young men.

Information-Theoretic Analysis of Cardiorespiratory Interactions during Apneic Events in Sleep

2020

In this work, measures of information dynamics are used to describe the dynamics of heart rate and cardiorespiratory interaction associated to sleep breathing disorders. In a large group of patients reporting repeated episodes of hypopneas, apneas (central, obstructive, mixed) and respiratory effort related arousals (RERA), we computed information storage of heart period variability and information transfer from heart period to airflow amplitude before, during and after each event. We find a general tendency to decrease of the information storage, suggesting higher complexity of the cardiac dynamics. The information transfer decreased during apneic events, and increased during milder disord…

Cardiac pacemaker function of HCN4 channels in mice is confined to embryonic development and requires cyclic AMP.

2008

Important targets for cAMP signalling in the heart are hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels that underlie the depolarizing 'pacemaker' current, I(f). We studied the role of I(f) in mice, in which binding of cAMP to HCN4 channels was abolished by a single amino-acid exchange (R669Q). Homozygous HCN4(R669Q/R669Q) mice die during embryonic development. Prior to E12, homozygous and heterozygous embryos display reduced heart rates and show no or attenuated responses to catecholaminergic stimulation. Adult heterozygous mice display normal heart rates at rest and during exercise. However, following beta-adrenergic stimulation, hearts exhibit pauses and sino-atrial…

The Effects of Epinine on Arterial Blood Pressure and Regional Vascular Resistances in Anesthetized Rats

1998

1. We carried out experiments in anesthetized rats to study the hemodynamic effects of intravenous injections of epinine. 2. Epinine (1-320 micrograms/kg) produced a biphasic effect on mean arterial blood pressure (n = 30). At doses lower than 40 micrograms/kg, arterial blood pressure decreased (by as much as 21.5 +/- 3.4%), though at higher doses it increased dose dependently (by as much as 73.2 +/- 14.5%). Epinine also produced bradicardia in a dose-dependent manner (by as much as 26.4 +/- 4.9%). Sulpiride (100 micrograms/kg) suppressed the hypotensive effect of epinine but did not change the hypertensive effect. In the presence of prazosin (1,000 micrograms/kg), arterial blood pressure r…

Analytical parameters and vital signs in patients subjected to dental extraction.

2017

BACKGROUND: Dental consultation may provoke stress to the patient, especially when a dental surgery is going to be performed, stressful situations can cause a reaction in the sympathetic nervous system that could lead to cardiovascular alterations. Blood pressure and cardiac frequency are used often as an indirect measurement and this parameters combined can serve as good indicators of stress. Objective: Analyze the changes in vital signs and analytical parameters induced by a dental extraction. MATERIAL AND METHODS: 24 healthy patients who required a simple dental extraction underwent to a blood test and motorization of their pre- and post-extraction vital signs before, at 2 and 48 hours a…

Intravenous propofol allows fast intubation in neonates and young infants undergoing major surgery

2019

Aim of the study: In selected surgical neonates and infants, the rapidity of induction and intubation may represent an important factor for their safety. Propofol is an anesthetic characterized by a rapid onset and fast recovery time that may reduce time of anesthetic induction and improve post-anesthetic outcome. The aim of this study was to evaluate the safety and efficacy of anesthesia induction in full-term neonates and young infants after propofol bolus administration.Methods: A retrospective case-control study including infants below 6 months of age, undergoing general anesthesia between 2011 and 2013, was carried out. Patients that received intravenous propofol bolus to induce anesth…

Do Obese Children Achieve Maximal Heart Rate during Treadmill Running?

2019

Objective: Maximal heart rate (HR) is commonly defined as the highest HR obtained during a progressive exercise test to exhaustion. Maximal HR is considered one of the criteria to assess maximum exertion in exercise tests, and is broadly used when prescribing exercise intensity. The aim of the present study was to compare peak HR measurements during maximal treadmill running and active play in obese children and adolescents. Design: Comparison of peak heart rate during active play vs. maximal treadmill running in 39 (7&ndash