scholarly journals Haemodynamic effects of hyperventilation on healthy men with different levels of autonomic tone

2020 ◽  
Vol 11 (1) ◽  
pp. 13-21
Author(s):  
V. A. Zavhorodnia ◽  
O. I. Androshchuk ◽  
T. H. Kharchenko ◽  
L. I. Kudii ◽  
S. O. Kovalenko
Keyword(s):  
Recovery Period ◽  
Peripheral Resistance ◽  
Stroke Index ◽  
Autonomic Tone ◽  
Polar Wind ◽  
Cardiorespiratory System ◽  
Phase Duration ◽  
Ejection Speed ◽  
Different Levels ◽  
Ejection Phase

The topicality of the research is stipulated by insufficient study of the correlation between the functional state of the cardiorespiratory system and autonomic tone. The goal of the research was to analyze the changes of central haemodynamics with 10-minute regulated breathing at the rate of 30 cycles per minute and within 40 minutes of recovery after the test in healthy young men with different levels of autonomic tone. Records of the chest rheoplethysmogram were recorded on a rheograph KhAI-medica standard (KhAI-medica, Kharkiv, Ukraine), a capnogram - in a lateral flow on a infrared capnograph (Datex, Finland), and the duration of R-R intervals was determined by a Polar WIND Link in the program of Polar Protrainer 5.0 (Polar Electro OY, Finland). Systolic and diastolic blood pressure were measured by Korotkov’s auscultatory method by mercury tonometer (Riester, Germany). The indicator of the normalized power of the spectrum in the range of 0.15–0.40 Hz was evaluated by 5-minute records; three groups of persons were distinguished according to its distribution at rest by the method of signal deviation, namely, sympathicotonic, normotonic and parasympathicotonic. The initial level of autonomic tone was found to impact the dynamics of СО2 level in alveolar air during hyperventilation and during recovery thereafter. Thus, PetCО2 was higher (41.3 mm Hg) in parasympathicotonic than in sympathicotonic (39.3 mm Hg) and normotonic (39.5 mm Hg) persons. During the test, R-R interval duration decreased being more expressed in normotonic persons. At the same time, the heart index was found to increase in three groups, and general peripheral resistance – to decrease mostly in normo- and parasympathicotonic persons. In addition, the reliable increase of stroke index and heart index was found in these groups. In the recovery period after hyperventilation, the decrease of tension index and ejection speed was found in normo- and, particularly, parasympathicotonic compared with sympathicotonic men and the increase of tension phase and ejection phase duration.

Central hemodynamics during progressive upper- and lower-body exercise and recovery

1984 ◽  
Vol 57 (2) ◽  
pp. 366-370 ◽  
Author(s):  
D. S. Miles ◽  
M. N. Sawka ◽  
D. E. Hanpeter ◽  
J. E. Foster ◽  
B. M. Doerr ◽  
...  
Keyword(s):  
Myocardial Contractility ◽  
Impedance Cardiography ◽  
Recovery Period ◽  
Peripheral Resistance ◽  
Cycle Ergometer ◽  
Lower Body ◽  
Central Hemodynamics ◽  
Rest Periods ◽  
Ergometer Exercise ◽  
Contractility Indices

The purpose of this study was to compare stroke volume (SV) and myocardial contractility responses during and immediately after upper- and lower-body exercise. Nine men (mean 28 yr, 78 kg) completed progressive intensity discontinuous tests on both an arm crank and cycle ergometer. Exercise for each power output (PO) was 7 min with 20-min rest periods interspersed. Impedance cardiography was used to measure cardiac output (Q), SV, and contractility on a beat-by-beat basis during exercise and a 15-s recovery period. Q increased linearly, and total peripheral resistance decreased exponentially with increasing PO levels. During recovery from exercise, the Q and heart rate (HR) values decreased immediately at all PO levels. When the exercise VO2 exceeded 1.0 1 X min-1, SV fell significantly during recovery for both exercise modes. In general, the recovery myocardial contractility indices remained similar to exercise values. It was concluded that immediately after low intensities of exercise, Q decreases because of a fall in HR. After moderate- and high-intensity exercise, Q decreases because of a fall in both HR and SV.

Cardiac Output by the Dye Dilution Technique Under Thiopental Sodium-Oxygen and Ether Anesthesia

1956 ◽  
Vol 186 (1) ◽  
pp. 101-104 ◽  
Author(s):  
Esther M. Greisheimer ◽  
Dorothy W. Ellis ◽  
George Stewart ◽  
Lydia Makarenko ◽  
Nadia Oleksyshyn ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cardiac Output ◽  
Arterial Blood Pressure ◽  
Total Peripheral Resistance ◽  
Peripheral Resistance ◽  
Stroke Index ◽  
Ether Anesthesia ◽  
Dye Dilution ◽  
Arterial Blood ◽  
Thiopental Sodium

One hundred-twenty determinations of cardiac output by the dye dilution technic utilizing the cuvette oximeter were made on 20 dogs. Of these, 60 were done under thiopental sodium-oxygen analgesia and 60 were done after supplementing with ether. Arterial blood pressure was recorded by strain gauge. Electrocardiograms were taken periodically. Concentrations of thiopental and ether in arterial blood were determined. Cardiac output began to increase under thiopental analgesia and continued to increase when ether was administered. Arterial blood pressure and heart rate decreased slightly when ether was administered. Stroke index increased when ether was administered. Total peripheral resistance decreased markedly under thiopental analgesia, and continued to decrease when ether was administered. When compared with an earlier study in which cyclopropane was used as the supplementing agent, it was found that cyclopropane and ether exert opposite effects on cardiac output and peripheral resistance despite the fact that the effect on arterial blood pressure is similar under the two agents. Increase in cardiac output was found to be parallel with decrease in total peripheral resistance in this study. Amount of dye injected did not influence cardiac output. Under the conditions of this study, cardiac output was in no way dependent on the concentration of thiopental in the blood nor on the amount injected. Level of ether in the blood did not show much effect, if any, on cardiac output. It is probable that the changes observed in this study are comparable with those which obtain clinically when thiopental-oxygen analgesia is supplemented with ether. Systolic blood pressure is not an infallible guide to other cardiovascular functions since it may remain fairly steady while cardiac output and peripheral resistance undergo marked changes under anesthesia.

scholarly journals The influence of nicergoline on cerebral, systemic and cardiac hemodynamics in patients who have had an ischemic stroke

2021 ◽  
pp. 17-26
Author(s):  
Viktor Kuznetsov
Keyword(s):  
Ischemic Stroke ◽  
Recovery Period ◽  
Peripheral Resistance ◽  
Cerebral Hemodynamics ◽  
Stroke Patients ◽  
Hemispheric Stroke ◽  
Cardiac Hemodynamics ◽  
Before And After ◽  
Blood Flow Velocities ◽  
The Right

The Aim of study was analysis of the effect of nicergoline on the cerebral, cardiac, systemic hemodynamics of patients after ischemic stroke, taking into account the hemispheric localization of the ischemic focus. Materials and methods. A comprehensive clinical and neurological examination was carried out in 38 elderly patients (mean age 64.3 ± 2.5 years) who had undergone atherothrombotic ischemic stroke in the carotid system (recovery period). There were 20 patients with left hemispheric stroke and 18 with right hemispheric stroke. All patients had arterial hypertension (AH). These were ACE inhibitors (enalapril 10-20 mg 1 tablet 2 times a day) and hydrochlorothiazide at a dose of 12.5 mg. Patients received nicergoline at a dose of 4 mg IV drip for 10 days. A comprehensive examination was carried out before and after treatment with nicergoline. The Results of the study allowed us to conclude that the course of nicergoline intake in patients after ischemic atherothrombotic stroke improves the subjective state and reduces the severity of neurological disorders, cerebral hemodynamics, increases linear systolic blood flow velocities (LBFVsys) and reduces peripheral resistance in individual extra- and intracranial vessels of the carotid and vertebro-basilar basins. In patients with right and left hemispheric localization of stroke under the influence of nicergoline, LBFVsys increases in the right and left ICA, PCA, and VA. In addition, LBFVsys increases in patients with right hemispheric stroke in the right MBA; in patients with left hemisphere - in two MBA and BA. In ischemic stroke patients, nicergoline affects systemic and cardiac hemodynamics: it reduces the systemic and cardiac hemodynamics, decreases the systemic vascular resistance and increases the ejection fraction, changes the structure of the relationship between systemic and cerebral hemodynamics, forming a positive relationship between blood pressure and hemodynamics in the vessels of the vertebro-basilar basin. Thus, the complex positive effect of nicergoline on various levels of cerebral, systemic and cardiac hemodynamics in ischemic stroke patients gives grounds to recommend the inclusion of this drug in the rehabilitation system of this category of patients.

Coronary and total peripheral resistance changes during sleep in a porcine model

1996 ◽  
Vol 270 (2) ◽  
pp. H723-H729 ◽  
Author(s):  
S. M. Zinkovska ◽  
E. K. Rodriguez ◽  
D. A. Kirby
Keyword(s):  
Heart Rate ◽  
Eye Movement ◽  
Rem Sleep ◽  
Total Peripheral Resistance ◽  
Sleep Stage ◽  
Peripheral Resistance ◽  
Nrem Sleep ◽  
Rapid Eye Movement ◽  
Autonomic Tone ◽  
Awake State

Changes in autonomic tone in the vasculature during sleep may have important implications for silent ischemia and sudden cardiac death. Few models exist in which both cardiac output and coronary blood flow are continuously measured during natural sleep and autonomic mechanisms are assessed. Catheters were chronically implanted in the aorta to measure mean arterial pressure (MAP), and flow probes were placed on the ascending aorta and the circumflex coronary artery of 18 pigs. Electrodes determined sleep stage as either non-rapid eye movement (NREM) or rapid eye movement (REM) sleep. The MAP was 73 +/- 3 mmHg in the quiet awake state, did not change in NREM, and decreased to 64 +/- 2 mmHg in REM sleep (P < 0.05). In NREM sleep, heart rate did not change from awake state values of 136 +/- 8 beats/min but increased by 5 beats/min in REM sleep (P < 0.05). Coronary vascular resistance decreased from awake state values of 2.7 +/- 0.2 to 2.2 +/- 0.2 mmHg.ml-1.min in REM (P < 0.05); total peripheral resistance decreased from awake values of 0.061 +/- 0.004 mmHg.ml-1.min to 0.050 +/- 0.003 in REM sleep (P < 0.05). Those changes appear to have been mediated primarily by reduction of alpha-adrenergic activity. Spectral analysis of heart rate suggests that power in the high-frequency range (a presumed indicator of parasympathetic tone) was lower in REM sleep than NREM sleep.

THE INDICATORS OF THE CARDIORESPIRATORY SYSTEM OF RATS UNDER THE ACTION OF ACETYLSALICYLIC ACID IN DIFFERENT CONCENTRATIONS

2020 ◽  
Vol 6(72) (1) ◽  
pp. 150-161
Author(s):  
M. Yu. Ravaeva ◽  
E. N. Chuyan ◽  
I. S. Mironyuk ◽  
I. V. Cheretaev ◽  
A. V. Pivovarchuk ◽  
...  
Keyword(s):  
Blood Flow ◽  
Acetylsalicylic Acid ◽  
Peripheral Resistance ◽  
Control Group ◽  
Cardiorespiratory System ◽  
Doppler Flowmetry ◽  
Scientific Equipment ◽  
Maximum Decrease ◽  
Reported Study ◽  
Almost All

The present study is devoted to revealing the peculiarities of the reaction of tissue microhemodynamics and cardiorespiratory system of animals the action acetylsalicylic acid in different concentrations on in rats. The study was carried out on the basis of the Center for collective use of scientific equipment «Experimental Physiology and Biophysics» of the Department of Human and Animal Physiology and Biophysics of the V. I. Vernadsky Crimean Federal University. The animals were divided into six groups of 10 animals. The first group was biological control; in the animals of this group, the microcirculation parameters were recorded by the laser Doppler flowmetry (LDF) method. The second-sixth group of animals was registered parameters of microcirculation and cardiorespiratory system. The LDF-metry was performed with the help of the laser analyzer of the blood flow «LAZMA-MC». It was researched the action of 5, 10, 40, 80, and 120 mg/kg doses acetylsalicylic acid on cardiorespiratory parameters in rats. It was found that the effect of acetylsalicylic acid in all doses significantly decreased only heart rate. The maximum decrease in this indicator was registered in animals when acetylsalicylic acid was administered at a dose of 120 mg/kg by 24.4 % (p≤0.05) relative to the values in the control group of animals. When acetylsalicylic acid was administered in isolated doses, there was a significant change in the activity of almost all components of microvascular tone regulation. These changes were most pronounced when animals were administered acetylsalicylic acid at a dose of 80 mg/kg. Thus, the action of acetylsalicylic acid it was increased the endothelium-dependent vasodilation, blood flow to the nutritive microvasculars, improvement in venular outflow and decreased in peripheral resistance. The reported study was funded by RFBR, project number 20-33-70142.

Effects of Carnosine on the Toxicity of Doxorubicin in Rabbits and Mice

Pteridines ◽  
2003 ◽  
Vol 14 (3) ◽  
pp. 94-101 ◽  
Author(s):  
Remigiusz Zieba ◽  
Elzbieta Czarnecka ◽  
Małgorzata Wągrowska-Danilewicz ◽  
Malgorzata Dzielska-Olczak ◽  
Julita Graczyk
Keyword(s):  
Mean Arterial Pressure ◽  
Cardiac Index ◽  
Arterial Pressure ◽  
Cardiac Muscle ◽  
Total Peripheral Resistance ◽  
Rabbit Model ◽  
Peripheral Resistance ◽  
Stroke Index ◽  
Haemodynamic Parameters ◽  
Doxorubicin Administration

Abstract The aim of this study was to establish the effect of naturally occurring antioxidant - carnosine - on the doxorubicin induced cardiotoxicity in a rabbit model. For this purpose we evaluated the influence of doxorubicin administration alone and in a combined therapy with carnosine on the haemodynamic parameters and on the degree of cardiac muscle cells alterations in rabbits. The rabbits were divided into four groups. One group of rabbits was injccted with doxorubicin in a dose of 2 mg kg-1 weekly for 7 weeks to induce congestive heart failure. Another group of rabbits received the same doses of doxorubicin simultaneously with carnosine in a dose of 100 mg kg1 p.o. daily for 9 weeks. Administration of carnosine was started 1 week prior to the first dose of doxorubicin and was ended one week after the administration of the last dose of doxorubicin. The control groups of animals received 0.9% NaCl and carnosine alone. The following haemodynamic parameters were estimated: heart rate, mean arterial pressure, cardiac index, stroke index and total peripheral resistance. Registration of the haemodynamic parameters in rabbits was performed by Doppler method. Carnosine normalised the values of mean arterial pressure in rabbits receiving doxorubicin, and increased the values of cardiac index and stroke index. The influence of carnosine on total peripheral resistance was not statistically significant, but there was a decreasing tendency. The degree of cardiac muscle cell alterations was examined by light microscopy using Mean Total Score technique. The histopathological studies revealed smaller damage of cardiac muscle in rabbits which received doxorubicin and carnosine, in comparison to animals receiving doxorubicin alone. Carnosine seems to be car dioprotective during doxorubicin administration

Cardiovascular Functions Under Chloralose-Urethane and 21-Hydroxypregnane-3,20 Dione Sodium Succinate (Viadril)

1957 ◽  
Vol 190 (2) ◽  
pp. 317-319 ◽  
Author(s):  
Esther M. Greisheimer ◽  
Dorothy W. Ellis ◽  
George H. Stewart ◽  
Lydia Makarenko ◽  
M. J. Oppenheimer
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Index ◽  
Sodium Succinate ◽  
Peripheral Resistance ◽  
Mean Blood Pressure ◽  
Stroke Index ◽  
Mean Values ◽  
The Mean ◽  
Cardiovascular Functions

Fifty-five determinations of cardiovascular functions were made on eight dogs under chloralose-urethane anesthesia and forty-one on six dogs under 21-hydroxypregnane-3,20 dione sodium succinate (Viadril). No preanesthetic medication was used. Cardiac output was determined by the dye dilution technique, using the cuvette oximeter. Blood pressure was determined by strain gauge. The mean values found under chloralose-urethane were: cardiac index 4.08, mean blood pressure 146 mm Hg, peripheral resistance 5709 dynes/sec/cm–5, heart rate 149 beats/min. and stroke index 27 cc. The mean values found under 21-hydroxypregnane-3, 20 dione sodium succinate were: cardiac index 5.15, mean blood pressure 104 mm Hg, peripheral resistance 3997 dynes/sec/cm–5, heart rate 172 beats/min. and stroke index 29 cc. When successive determinations were made within a short period of time, the cardiac index and stroke index increased, peripheral resistance decreased and blood pressure and heart rate remained fairly steady.

Effects of gender and hypovolemia on sympathetic neural responses to orthostatic stress

2005 ◽  
Vol 289 (1) ◽  
pp. R109-R116 ◽  
Author(s):  
Qi Fu ◽  
Sarah Witkowski ◽  
Kazunobu Okazaki ◽  
Benjamin D. Levine
Keyword(s):  
Blood Pressure ◽  
Stroke Volume ◽  
Lower Body Negative Pressure ◽  
Muscle Sympathetic Nerve Activity ◽  
Peripheral Resistance ◽  
Orthostatic Stress ◽  
Stroke Index ◽  
Orthostatic Tolerance ◽  
Neural Responses ◽  
Men And Women

We tested the hypothesis that women have blunted sympathetic neural responses to orthostatic stress compared with men, which may be elicited under hypovolemic conditions. Muscle sympathetic nerve activity (MSNA) and hemodynamics were measured in eight healthy young women and seven men in supine position and during 6 min of 60° head-up tilt (HUT) under normovolemic and hypovolemic conditions (randomly), with ∼4-wk interval. Acute hypovolemia was produced by diuretic (furosemide) administration ∼2 h before testing. Orthostatic tolerance was determined by progressive lower body negative pressure to presyncope. We found that furosemide produced an ∼13% reduction in plasma volume, causing a similar increase in supine MSNA in men and women (mean ± SD of 5 ± 7 vs. 6 ± 5 bursts/min; P = 0.895). MSNA increased during HUT and was greater in the hypovolemic than in the normovolemic condition (32 ± 6 bursts/min in normovolemia vs. 44 ± 15 bursts/min in hypovolemia in men, P = 0.055; 35 ± 9 vs. 45 ± 8 bursts/min in women, P < 0.001); these responses were not different between the genders (gender effect: P = 0.832 and 0.814 in normovolemia and hypovolemia, respectively). Total peripheral resistance increased proportionately with increases in MSNA during HUT; these responses were similar between the genders. However, systolic blood pressure was lower, whereas diastolic blood pressure was similar in women compared with men during HUT, which was associated with a smaller stroke volume or stroke index. Orthostatic tolerance was lower in women, especially under hypovolemic conditions. These results indicate that men and women have comparable sympathetic neural responses during orthostatic stress under normovolemic and hypovolemic conditions. The lower orthostatic tolerance in women is predominantly because of a smaller stroke volume, presumably due to less cardiac filling during orthostasis, especially under hypovolemic conditions, which may overwhelm the vasomotor reserve available for vasoconstriction or precipitate neurally mediated sympathetic withdrawal and syncope.

Venom injection by rattlesnakes (Crotalus atrox): peripheral resistance and the pressure-balance hypothesis

2003 ◽  
Vol 81 (2) ◽  
pp. 313-320 ◽  
Author(s):  
Bruce A Young ◽  
Molly Phelan ◽  
Malinda Morain ◽  
Melissa Ommundsen ◽  
Robert Kurt
Keyword(s):  
High Speed ◽  
Peripheral Resistance ◽  
Venom Gland ◽  
Pressure Balance ◽  
Crotalus Atrox ◽  
Digital Videos ◽  
Balance Hypothesis ◽  
External Forces ◽  
The Right ◽  
Different Levels

Differential venom injection by snakes, between two size classes of prey for example, has typically been explained within the rubric of the venom-metering hypothesis, which claims that snakes decide how much venom to inject in a given strike. Recently, an alternative, the pressure-balance hypothesis, was advanced, which attributes differential venom flow to the balance of internal forces acting at the venom gland and venom chambers and external forces acting at the exit orifice of the fang. This study tests these competing hypotheses. High-speed digital videos of predatory and defensive strikes by western diamondback rattlesnakes, Crotalus atrox, revealed considerable variation in the trajectory of the fang relative to the target, which would yield wounds with potentially different levels of peripheral resistance. The importance of peripheral resistance was also suggested by the expulsion of venom from the fang after withdrawal from the target (in 7% of strikes) and by the forceful ejection of fluid from the target around the embedded fang (in 2.8% of strikes). Experimental milking chambers were constructed that exposed the right and left venom-delivery systems to different levels of peripheral resistance; with increased peripheral resistance significantly less venom was injected into the chamber and significantly more venom was released on the chamber's surface.

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