scholarly journals Quantification of the Feedback Regulation by Digital Signal Analysis Methods: Application to Blood Pressure Control Efficacy

2019 ◽  
Vol 10 (1) ◽  
pp. 209 ◽  
Author(s):  
Nikita S. Pyko ◽  
Svetlana A. Pyko ◽  
Oleg A. Markelov ◽  
Oleg V. Mamontov ◽  
Mikhail I. Bogachev
Keyword(s):  
Blood Pressure ◽  
Stress Test ◽  
Digital Signal ◽  
External Input ◽  
The Body ◽  
Differential Diagnostics ◽  
Pulse Interval ◽  
Control Mechanisms ◽  
Pressure Changes ◽  
Feedback Responses

Six different metrics of mutual coupling of simultaneously registered signals representing blood pressure and pulse interval dynamics have been considered. Stress test responses represented by the reaction of the recorded signals to the external input by tilting the body into the upright position have been studied. Additionally, to the conventional metrics like the joint signal coherence Coher and the sensitivity of the pulse intervals response to the blood pressure changes baroreflex sensitivity (BRS), also alternative indicators like the synchronization coefficient Sync and the time delay stability estimate TDS representing the temporal fractions of the analyzed signal records exhibiting rather synchronous dynamics have been determined. In contrast to BRS, that characterizes the intensity of the pulse intervals response to the blood pressure changes during observed feedback responses, both Sync and TDS likely indicate how often such responses are being activated in the first place. The results indicate that in most cases BRS is typically reciprocal to both Sync and TDS suggesting that low intensity of the feedback responses characterized by low BRS is rather compensated by their more frequent activation indicated by higher Sync and TDS. The proposed additional indicators could be complementary for the differential diagnostics of blood pressure regulation efficacy and also lead to a deeper insight into the involved concomitant factors this way also aiming at the improvement of the mathematical models representing the underlying feedback control mechanisms.

Changes in Blood Pressure, Heart Rate and Breathing Rate During Moderate Swimming Activity in Rainbow Trout

1967 ◽  
Vol 46 (2) ◽  
pp. 307-315 ◽  
Author(s):  
E. DON STEVENS ◽  
D. J. RANDALL
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Rainbow Trout ◽  
Venous Blood ◽  
The Body ◽  
Swimming Activity ◽  
Breathing Rate ◽  
Blood Pressures ◽  
Ventral Aorta ◽  
Pressure Changes

1. Changes in blood pressure in the dorsal aorta, ventral aorta and subintestinal vein, as well as changes in heart rate and breathing rate during moderate swimming activity in the rainbow trout are reported. 2. Blood pressures both afferent and efferent to the gills increased during swimming and then returned to normal levels within 30 min. after exercise. 3. Venous blood pressure was characterized by periodic increases during swimming. The pressure changes were not in phase with the body movements. 4. Although total venous return to the heart increased during swimming, a decreased blood flow was recorded in the subintestinal vein. 5. Heart rate and breathing rate increased during swimming and then decreased when swimming ceased. 6. Some possible mechanisms regulating heart and breathing rates are discussed.

Heart rate and blood pressure changes during sleep-waking cycles and cataplexy in narcoleptic dogs

1989 ◽  
Vol 256 (1) ◽  
pp. H111-H119 ◽  
Author(s):  
J. M. Siegel ◽  
K. S. Tomaszewski ◽  
H. Fahringer ◽  
G. Cave ◽  
T. Kilduff ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Rem Sleep ◽  
Muscle Tone ◽  
Canine Model ◽  
Control Mechanisms ◽  
Athletic Activity ◽  
Onset Period ◽  
Pressure Changes ◽  
Cardiovascular Variables

Cataplexy is the abrupt loss of muscle tone experienced by narcoleptics. It is usually precipitated by strong emotions or athletic activity. It has been hypothesized that cardiovascular variables have a role in the triggering of cataplexy. In the present study, we have utilized the narcoleptic canine model to directly investigate changes in heart rate and blood pressure in relation to cataplectic episodes. We found that heart rate increased 18% on average in the 20 s preceding cataplexy onset and then fell during cataplexy. Thus, from a cardiovascular standpoint, cataplexy can be subdivided into two very different periods, the cataplexy onset period with very high and declining heart rate, and the period greater than or equal to 10 s after onset, with greatly reduced heart rate. Heart rate at cataplexy onset was significantly higher than heart rate in rapid-eye-movement (REM) sleep, non-REM sleep, and quiet waking. Blood pressure did not markedly change before the onset of spontaneous cataplexies but decreased significantly during cataplexy. Although blood pressure increases did not precede spontaneous cataplexies, sudden increases in blood pressure, induced pharmacologically or by obstruction of the descending aorta, triggered cataplexy in the most severely affected subjects. A hypothesized role for cataplexy as a homeostatic reflex, triggered by interactions between blood flow, central chemoreceptors, and atonia control mechanisms in the medial medulla, is discussed.

Short-term and long-term blood pressure and heart rate variability in the mouse

2000 ◽  
Vol 278 (1) ◽  
pp. R215-R225 ◽  
Author(s):  
Ben J. A. Janssen ◽  
Peter J. A. Leenders ◽  
Jos F. M. Smits
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Heart Rate ◽  
Pressure Fluctuations ◽  
Sympathetic Nerves ◽  
Pulse Interval ◽  
Control Mechanisms ◽  
Short Term ◽  
Endogenous Nitric Oxide ◽  
Short Term Variability

Knowledge on murine blood pressure and heart rate control mechanisms is limited. With the use of a tethering system, mean arterial pressure (MAP) and pulse interval (PI) were continuously recorded for periods up to 3 wk in Swiss mice. The day-to-day variation of MAP and PI was stable from 5 days after surgery. Within each mouse ( n = 9), MAP and PI varied by 21 ± 6 mmHg and 17 ± 4 ms around their respective 24-h averages (97 ± 3 mmHg and 89 ± 3 ms). Over 24-h periods, MAP and PI were bimodally distributed and clustered around two preferential states. Short-term variability of MAP and PI was compared between the resting (control) and active states using spectral analysis. In resting conditions, variability of MAP was mainly confined to frequencies <1 Hz, whereas variability of PI was predominantly linked to the respiration cycle (3–6 Hz). In the active state, MAP power increased in the 0.08- to 3-Hz range, whereas PI power fell in the 0.08- to 0.4-Hz range. In both conditions, coherence between MAP and PI was high at 0.4 Hz with MAP leading the PI fluctuations by 0.3–0.4 s, suggesting that reflex coupling between MAP and PI occurred at the same frequency range as in rats. Short-term variability of MAP and PI was studied after intravenous injection of autonomic blockers. Compared with the resting control state, MAP fell and PI increased after ganglionic blockade with hexamethonium. Comparable responses of MAP were obtained with the α-blocker prazosin, whereas the β-blocker metoprolol increased PI similarly. Muscarinic blockade with atropine did not significantly alter steady-state levels of MAP and PI. Both hexamethonium and prazosin decreased MAP variability in the 0.08- to 1-Hz range. In contrast, after hexamethonium and metoprolol, PI variability increased in the 0.4- to 3-Hz range. Atropine had no effect on MAP fluctuations but decreased those of PI in the 0.08- to 1-Hz range. These data indicate that, in mice, blood pressure and its variability are predominantly under sympathetic control, whereas both vagal and sympathetic nerves control PI variability. Blockade of endogenous nitric oxide formation by N G-nitro-l-arginine methyl ester increased MAP variability specifically in the 0.08- to 0.4-Hz range, suggesting a role of nitric oxide in buffering blood pressure fluctuations.

scholarly journals Psychosocial Distress and Blood Pressure among Young Adults: Role of Cortisol as Mediator

2018 ◽  
Vol 17 (1) ◽  
Author(s):  
Wan Fatein Wan Omar ◽  
Ramli Musa ◽  
Jamalludin A. Rahman ◽  
Azarisman Shah Mohd Shah ◽  
Norlelawati A. Talib ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Young Adults ◽  
Risk Factor ◽  
Stress Test ◽  
Fasting Blood Glucose ◽  
Serum Cortisol ◽  
Psychosocial Distress ◽  
The Body ◽  
Mediating Role

Introduction: Hypertension is the most prevalent risk factor of cardiovascular diseases in Malaysia. 17.3% of hypertension cases in Malaysia is attributed to adults aged 18 to 39 years. Psychosocial distress is a possible risk factor for elevated blood pressure in young adults, and cortisol could be the mediating factor. The aim of this study is to evaluate the mediating role of cortisol in hypertension and psychosocial distress in young adults. Materials and Methods: A comparative crosssectional study was conducted in 240 young adults aged 45 years or less. The body mass index, waist circumference and blood pressure parameters were recorded. Serum cortisol, creatinine, fasting blood glucose and lipid profile were measured following acute mental stress test. Psychosocial distress was assessed using the DASS-21 questionnaire. Results: Mean (standard deviation) values for SBP, DBP and MAP were 126.0 (16.3), 84.1 (12.2) and 98.1 (13.1) mmHg respectively. Anxiety was significantly associated with systolic blood pressure (β = 0.644), diastolic blood pressure (β = 0.454) and mean arterial pressure (β = 0.516) after adjusting to sex, age and cortisol. However, it was not mediated by cortisol. Depression and stress were not found to have any effect on blood pressure of the young adults studied. Conclusion: The data suggest that there is no elevated risk for psychosocial distress and hypertension that cortisol poses in young adults.

Critical closing pressure explains cerebral hemodynamics during the Valsalva maneuver

1999 ◽  
Vol 86 (2) ◽  
pp. 675-680 ◽  
Author(s):  
Suzanne L. Dawson ◽  
Ronney B. Panerai ◽  
John F. Potter
Keyword(s):  
Blood Pressure ◽  
Valsalva Maneuver ◽  
Intrathoracic Pressure ◽  
Pulse Interval ◽  
Cerebrovascular Resistance ◽  
Arterial Blood ◽  
Critical Closing Pressure ◽  
Pressure Changes ◽  
Closing Pressure ◽  
Phase Iv

The Valsalva maneuver (VM), a voluntary increase in intrathoracic pressure of ∼40 mmHg, has been used to examine cerebral autoregulation (CA). During phase IV of the VM there are pronounced changes in mean arterial blood pressure (MABP), pulse interval, and cerebral blood flow (CBF), but the changes in CBF are of a much greater magnitude than those seen in MABP, a finding to date attributed to either a delay in activation of the CA mechanism or the inability of this mechanism to cope with the size and speed of the blood pressure changes involved. These changes in CBF also precede those in MABP, a pattern of events not explained by the physiological process of CA. Measurements of CBF velocity (transcranial Doppler) and MABP (Finapres) were performed in 53 healthy volunteers (aged 31–80 yr). By calculating beat-to-beat values of critical closing pressure (CCP) during the VM, we have found that this parameter suddenly drops at the start of phase IV, providing a coherent explanation for the large increase in CBF. If CCP is included in the estimation of cerebrovascular resistance, a temporal pattern more consistent with an autoregulatory response to the MABP overshoot is also found. CCP is intricately involved in the control of CBF during the VM and should be considered in the assessment of CA.

scholarly journals Psychosocial Distress and Blood Pressure among Young Adults: Role of Cortisol as Mediator

2020 ◽  
Vol 18 (2) ◽  
Author(s):  
Wan Fatein Nabeila W.O. ◽  
Azarisman S.M.S ◽  
Jamalludin A.R. ◽  
Norlelawati A.T. ◽  
Ramli M. ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Young Adults ◽  
Risk Factor ◽  
Stress Test ◽  
Fasting Blood Glucose ◽  
Serum Cortisol ◽  
Psychosocial Distress ◽  
The Body ◽  
Cross Sectional

Introduction: Hypertension is the most prevalent risk factor of cardiovascular diseases in Malaysia. 17.3% of hypertension cases in Malaysia is attributed to adults aged 18 to 39 years. Psychosocial distress is a possible risk factor for elevated blood pressure in young adults, and cortisol could be the mediating factor. The aim of this study is to evaluate the mediating role of cortisol in hypertension and psychosocial distress in young adults. Methods and materials: A comparative cross-sectional study was conducted in 240 young adults aged 18 to 45 years. The body mass index, waist circumference and blood pressure parameters were recorded. Serum cortisol, creatinine, fasting blood glucose and lipid profile were measured following acute mental stress test. Psychosocial distress was assessed using the DASS-21 questionnaire. Results: Mean (standard deviation) values for SBP, DBP, MAP were 126.0(16.3), 84.1(12.2) and 98.1(13.1) mmHg respectively. Anxiety was significantly associated with systolic blood pressure (β=0.644), diastolic blood pressure (β=0.454) and mean arterial pressure (β=0.516) after adjusting for sex, age and cortisol. However, it was not mediated by cortisol. Depression and stress were not found to have any effect on blood pressure of the young adults studied. Conclusion: The data suggest that there is no elevated risk for psychosocial distress and hypertension that cortisol poses in young adults.

Burnout of the Mind – Burnout of the Body?

2018 ◽  
Vol 32 (1) ◽  
pp. 30-42 ◽  
Author(s):  
Claudia Traunmüller ◽  
Kerstin Gaisbachgrabner ◽  
Helmut Karl Lackner ◽  
Andreas R. Schwerdtfeger
Keyword(s):  
Blood Pressure ◽  
Allostatic Load ◽  
Maslach Burnout Inventory ◽  
The Body ◽  
Lower Percentage ◽  
Control Group ◽  
Urinary Catecholamines ◽  
Morning Cortisol ◽  
The Mind ◽  
Cortisol Increase

Abstract. In the present paper we investigate whether patients with a clinical diagnosis of burnout show physiological signs of burden across multiple physiological systems referred to as allostatic load (AL). Measures of the sympathetic-adrenergic-medullary (SAM) axis and the hypothalamic-pituitary-adrenal (HPA) axis were assessed. We examined patients who had been diagnosed with burnout by their physicians (n = 32) and were also identified as burnout patients based on their score in the Maslach Burnout Inventory-General Survey (MBI-GS) and compared them with a nonclinical control group (n = 19) with regard to indicators of allostatic load (i.e., ambulatory ECG, nocturnal urinary catecholamines, salivary morning cortisol secretion, blood pressure, and waist-to-hip ratio [WHR]). Contrary to expectations, a higher AL index suggesting elevated load in several of the parameters of the HPA and SAM axes was found in the control group but not in the burnout group. The control group showed higher norepinephrine values, higher blood pressure, higher WHR, higher sympathovagal balance, and lower percentage of cortisol increase within the first hour after awakening as compared to the patient group. Burnout was not associated with AL. Results seem to indicate a discrepancy between self-reported burnout symptoms and psychobiological load.

Paradoxical Hypotension during Dobutamine Infusion for Myocardial Perfusion Scintigraphy

1998 ◽  
Vol 37 (08) ◽  
pp. 268-271
Author(s):  
B. Caner ◽  
E. Atalar ◽  
A. Karanfil ◽  
L. Tokgözoğlu ◽  
E. L. Ergün
Keyword(s):  
Blood Pressure ◽  
Myocardial Perfusion ◽  
Systolic Blood Pressure ◽  
Myocardial Perfusion Scintigraphy ◽  
Stress Test ◽  
Dobutamine Infusion ◽  
Perfusion Scintigraphy ◽  
Tilt Table ◽  
Study Results ◽  
Group A

Summary Aim: Dobutamine as a predominant beta-1 agonist increases heart rate and myocardial contractility and at sufficient high doses, it also increases systolic blood pressure. This study was undertaken to describe instances of paradoxical hypotension during dobutamine infusion for TI-201 myocardial perfusion SPECT study and the relationship between scintigraphic findings and hypotension occurred during dobutamine infusion. Methods: In 201 consecutive patients unable to perform adequate exercise, dobutamine TI-201 myocardial SPECT was performed. Dobutamine was infused starting from 10 μg/kg/min increasing to 40 μg/kg/min. Paradoxical hypotension was defined as a decrease in systolic blood pressure ≥ 20 mmHg compared with baseline study. Results: Paradoxical hypotension was observed in 40 patients (Group A) out of 201 (19.9%) while no significant change in systolic blood pressure was detected in the remaining 161 patients (Group B). Mean maximum fall in systolic blood pressure was 39 ± 18 mmHg (range: 20-90). In 33 of 40 patients (83%) with paradoxical hypotension, scintigraphy was normal compared to 131 (81%) of the remaining 161 patients. In patients of Group A, angiography, echocardiography and tilt table tests were performed in 13, 11 and 6 patients respectively. Nine of 13 angiographic evaluations (69%), 10 of 11 echocardiographic evaluations (91%), all of the tilt table tests were normal. Additionally, all of the patients of Group A were clinically followed up at least 6 months after the myocardial perfusion scintigraphy. None of the patients had a cardiac event except one patient during the follow-up period. Conclusion: Paradoxical hypotension during dobutamine infusion for myocardial scintigraphy is not an uncommon finding and up to 19.9% patients may develop such hypotension. To maximize test safety, precautions should be taken during dobutamine myocardial stress test, since remarkable decrease in systolic blood pressure may occur. Unlike hypotension occurring with exercise test, hypotension response to dobutamine is not always a marker for coronary artery disease.

Heart Rate Signal Decomposition

2000 ◽  
Vol 39 (02) ◽  
pp. 200-203
Author(s):  
H. Mizuta ◽  
K. Yana
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Pressure Change ◽  
Normal Subjects ◽  
Signal Decomposition ◽  
Large Individual ◽  
Heart Rate Fluctuations ◽  
Type Pattern ◽  
Signal Cancellation ◽  
Pressure Changes

Abstract:This paper proposes a method for decomposing heart rate fluctuations into background, respiratory and blood pressure oriented fluctuations. A signal cancellation scheme using the adaptive RLS algorithm has been introduced for canceling respiration and blood pressure oriented changes in the heart rate fluctuations. The computer simulation confirmed the validity of the proposed method. Then, heart rate fluctuations, instantaneous lung volume and blood pressure changes are simultaneously recorded from eight normal subjects aged 20-24 years. It was shown that after signal decomposition, the power spectrum of the heart rate showed a consistent monotonic 1/fa type pattern. The proposed method enables a clear interpretation of heart rate spectrum removing uncertain large individual variations due to the respiration and blood pressure change.

HIPEREMESIS GRAVIDARUM PADA IBU HAMIL DI KLINIK BIDAN SUPRIYATI SRIBIT BERBAH SLEMAN

2019 ◽  
Vol 14 (1) ◽  
pp. 51
Author(s):  
Pramukti Dian Setianingrum ◽  
Farah Irmania Tsani
Keyword(s):  
Blood Pressure ◽  
Pregnant Women ◽  
Hyperemesis Gravidarum ◽  
Unwanted Pregnancy ◽  
The Body ◽  
Nausea And Vomiting ◽  
Daily Activities ◽  
World Health ◽  
The World

Backgroud: The World Health Organization (WHO) explained that the number of Hyperemesis Gravidarum cases reached 12.5% of the total number of pregnancies in the world and the results of the Demographic Survey conducted in 2007, stated that 26% of women with live births experienced complications. The results of the observations conducted at the Midwife Supriyati Clinic found that pregnant women with hyperemesis gravidarum, with a comparison of 10 pregnant women who examined their contents there were about 4 pregnant women who complained of excessive nausea and vomiting. Objective: to determine the hyperemesis Gravidarum of pregnant mother in clinic. Methods: This study used Qualitative research methods by using a case study approach (Case Study.) Result: The description of excessive nausea of vomiting in women with Hipermemsis Gravidarum is continuous nausea and vomiting more than 10 times in one day, no appetite or vomiting when fed, the body feels weak, blood pressure decreases until the body weight decreases and interferes with daily activities days The factors that influence the occurrence of Hyperemesis Gravidarum are Hormonal, Diet, Unwanted Pregnancy, and psychology, primigravida does not affect the occurrence of Hyperemesis Gravidarum. Conclusion: Mothers who experience Hyperemesis Gravidarum feel nausea vomiting continuously more than 10 times in one day, no appetite or vomiting when fed, the body feels weak, blood pressure decreases until the weight decreases and interferes with daily activities, it is because there are several factors, namely, hormonal actors, diet, unwanted pregnancy, and psychology.

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