Heart Rate Variability Enhances the Accuracy of Non-invasive Continuous Blood Pressure Estimation Under Blood Loss

Abstract Background: To propose a new method for real-time monitoring of human blood pressure under blood loss (BPBL), this article combines pulse transit time (PTT) and heart rate variability (HRV) as input parameters in order to establish a model for the estimation of BPBL.Methods: Effective parameters such as PTT, R-R internal (RRI), and HRV were extracted and used to establish the blood pressure (BP) estimation. Three BP estimation models were established: the PTT model, the RRI model, and the HRV model, and they were divided into experimental group and control group. Finally, the effects of different estimation models on the accuracy of BPBL estimation were evaluated based on the experimental results.Results: The Pearson correlation coefficients R were 0.7731, 0.8943 and 0.9169 for the PTT model, the RRI model, and the HRV model, respectively. The root means square error of the estimation set (RMSEP) were 16.83 mmHg, 11.87 mmHg and 10.59 mmHg, respectively.Conclusion: The results suggest that the accuracy of the BPBL estimated by the RRI and HRV models is better than that of the PTT model, which means that both RRI and HRV can enhance the accuracy of BPBL estimation, and HRV seems to be more effective in improving the accuracy of BP prediction compared to RRI. These results provide a new idea for other scholars in the field of BPBL estimation research.

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Differential effects of the blood pressure state on pulse rate variability and heart rate variability in critically ill patients

npj Digital Medicine ◽

10.1038/s41746-021-00447-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Elisa Mejía-Mejía ◽

James M. May ◽

Mohamed Elgendi ◽

Panayiotis A. Kyriacou

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Pulse Rate ◽

Pulse Transit Time ◽

Pulse Rate Variability ◽

Physiological Factors ◽

Ecg Signals ◽

Non Invasive ◽

Electrocardiogram Ecg

AbstractHeart rate variability (HRV) utilizes the electrocardiogram (ECG) and has been widely studied as a non-invasive indicator of cardiac autonomic activity. Pulse rate variability (PRV) utilizes photoplethysmography (PPG) and recently has been used as a surrogate for HRV. Several studies have found that PRV is not entirely valid as an estimation of HRV and that several physiological factors, including the pulse transit time (PTT) and blood pressure (BP) changes, may affect PRV differently than HRV. This study aimed to assess the relationship between PRV and HRV under different BP states: hypotension, normotension, and hypertension. Using the MIMIC III database, 5 min segments of PPG and ECG signals were used to extract PRV and HRV, respectively. Several time-domain, frequency-domain, and nonlinear indices were obtained from these signals. Bland–Altman analysis, correlation analysis, and Friedman rank sum tests were used to compare HRV and PRV in each state, and PRV and HRV indices were compared among BP states using Kruskal–Wallis tests. The findings indicated that there were differences between PRV and HRV, especially in short-term and nonlinear indices, and although PRV and HRV were altered in a similar manner when there was a change in BP, PRV seemed to be more sensitive to these changes.

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Cardiovascular effects of reflexology in healthy individuals: evidence for a specific increase in blood pressure

Alternative Medicine Studies ◽

10.4081/ams.2012.e4 ◽

2012 ◽

Vol 2 (1) ◽

pp. 4 ◽

Cited By ~ 6

Author(s):

Elisabeth Ruiz Padial ◽

Nieves Torres López ◽

Javier Luna Bujaldón ◽

Isabel Espadas Villanueva ◽

Gustavo Reyes del Paso

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Waiting Time ◽

Healing Process ◽

Cardiovascular Effects ◽

Baroreceptor Reflex ◽

Control Group ◽

Time Control ◽

Baroreceptor Reflex Sensitivity

The present study evaluates the cardiovascular effects of reflexology in a healthy sample. Forty-one participants were randomly assigned to one of three experimental groups: reflexology (n=15), non-professional foot massage (n=14), and a waiting time control group (n=12). Dependent variables were systolic, diastolic and mean blood pressure, inter-beat interval, heart rate variability and baroreceptor reflex sensitivity measured pre- and post- interventions. The study was performed during three 40-min sessions separated by weekly intervals. Results show that the three manipulations produce similar increases in inter-beat interval, heart rate variability and baroreceptor reflex sensitivity. Reflexology specifically produces an increase in blood pressure, which increases gradually over the three sessions. The parallel increase in heart rate variability and baroreceptor reflex sensitivity together with the increase in blood pressure suggest that reflexology is associated with a co-activation of both sympathetic and parasympathetic branches of the Autonomic Nervous System. These changes could be helpful in optimizing homeostatic activity, promoting the healing process and increasing the human organism’s capacity to respond adaptively to internal and external challenges. Finally, the observed physiological changes in the waiting-time control group shows the relevance of habituation processes and suggests the need for addition of waiting-time control groups in future studies.

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Spectral Analysis of Heart Rate Variability during Trigger Point Acupuncture

Acupuncture in Medicine ◽

10.1136/acupmed-2013-010440 ◽

2014 ◽

Vol 32 (3) ◽

pp. 273-278 ◽

Cited By ~ 10

Author(s):

Yoji Kitagawa ◽

Kenichi Kimura ◽

Sohei Yoshida

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Spectral Analysis ◽

Tibialis Anterior ◽

Trigger Point ◽

Tibialis Anterior Muscle ◽

Trigger Points ◽

Control Group ◽

The Right

Objectives To clarify changes in the cardiovascular autonomic nervous system function due to trigger point acupuncture, we evaluated differences in responses between acupuncture at trigger points and those at other sites using spectral analysis of heart rate variability. Methods Subjects were 35 healthy men. Before measurements began the subjects were assigned to a trigger point acupuncture or control group based on the presence/absence of referred pain on applying pressure to a taut band within the right tibialis anterior muscle. The measurements were conducted in a room with a temperature of 25°C, with subjects in a long sitting position after 10 min rest. Acupuncture needles were retained for 10 min at two sites on the right tibialis anterior muscle. ECG was performed simultaneously with measurements of blood pressure and the respiratory cycle. Based on the R–R interval on the ECG, frequency analysis was performed, low-frequency (LF) and high-frequency (HF) components were extracted and the ratio of LF to HF components (LF/HF) was evaluated. Results The trigger point acupuncture group showed a transient decrease in heart rate and an increase in the HF component but no significant changes in LF/HF. In the control group, no significant changes were observed in heart rate, the HF component or LF/HF. There were no consistent changes in systolic or diastolic blood pressure in either group. Conclusions These data suggest that acupuncture stimulation of trigger points of the tibialis anterior muscle transiently increases parasympathetic nerve activity.

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Effect of Continuous Infusion of Dexmedetomidine on Blood Loss in Orthognathic Surgery: A Retrospective Study

10.21203/rs.3.rs-131518/v1 ◽

2020 ◽

Author(s):

Chenyu Jin ◽

Hong Jiang ◽

Xiang Lv ◽

Yu Sun

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Blood Loss ◽

Haemoglobin Level ◽

Continuous Infusion ◽

Orthognathic Surgery ◽

Fluid Volume ◽

Control Group ◽

Postoperative Haemoglobin ◽

Decrease Blood Loss

Abstract Background: Patients with maxillofacial deformities require orthognathic surgeries to correct occlusion. The surgical procedure may lead to massive bleeding, which is associated with hematoma, respiratory obstruction, and asphyxia. Dexmedetomidine has been used in controlled hypotension, and may decrease blood loss in orthognathic surgery. We conducted a retrospective cohort study to evaluate the effect of dexmedetomidine on blood loss in orthognathic surgeries.Methods: The primary outcome examined was blood loss, and secondary outcomes were postoperative haemoglobin level, intraoperative heart rate, and blood pressure (T0: preoperative; T1: at incision; T2: 30 minutes after incision; T3: 60 minutes after incision; T4: 120 minutes after incision); dose of fentanyl, remifentanil, urapidil, and esmolol; operation time; incidence of allogeneic blood transfusion; crystalloid fluids volume; and colloidal fluid volume. Results: A total of 1,247 patients were included in the study, and 557 patient pairs were matched via propensity score matching. There were significant decreases in mean blood loss, heart rate at T1–T4, blood pressure at T1, remifentanil and esmolol dosage, and crystalloid fluid volume in the dexmedetomidine group compared with those in the control group. There was also a significant increase in the postoperative haemoglobin level of the dexmedetomidine group. Conclusions: Continuous infusion of dexmedetomidine can decrease blood loss in orthognathic surgery.Trial registration number: ChiCTR1800018794 (retrospectively registered)Name of registry: Chinese Clinical Trial RegistryDate of registration: 2018/10/09URL: www.chictr.org.cn/showproj.aspx?proj=30612

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Autonomic Cardiovascular Dysregulation at Rest and During Stress in Chronically Low Blood Pressure

Journal of Psychophysiology ◽

10.1027/0269-8803/a000204 ◽

2019 ◽

Vol 33 (1) ◽

pp. 39-53 ◽

Cited By ~ 1

Author(s):

Stefan Duschek ◽

Alexandra Hoffmann ◽

Casandra I. Montoro ◽

Gustavo A. Reyes del Paso

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Cardiac Output ◽

Stroke Volume ◽

Total Peripheral Resistance ◽

Baroreflex Sensitivity ◽

Peripheral Resistance ◽

Control Group ◽

Low Blood Pressure

Abstract. Chronic low blood pressure (hypotension) is accompanied by symptoms such as fatigue, reduced drive, faintness, dizziness, cold limbs, and concentration difficulties. The study explored the involvement of aberrances in autonomic cardiovascular control in the origin of this condition. In 40 hypotensive and 40 normotensive subjects, impedance cardiography, electrocardiography, and continuous blood pressure recordings were performed at rest and during stress induced by mental calculation. Parameters of cardiac sympathetic control (i.e., stroke volume, cardiac output, pre-ejection period, total peripheral resistance), parasympathetic control (i.e., heart rate variability), and baroreflex function (i.e., baroreflex sensitivity) were obtained. The hypotensive group exhibited markedly lower stroke volume, heart rate, and cardiac output, as well as higher pre-ejection period and baroreflex sensitivity than the control group. Hypotension was furthermore associated with a smaller blood pressure response during stress. No group differences arose in total peripheral resistance and heart rate variability. While reduced beta-adrenergic myocardial drive seems to constitute the principal feature of the autonomic impairment that characterizes chronic hypotension, baroreflex-related mechanisms may also contribute to this state. Insufficient organ perfusion due to reduced cardiac output and deficient cardiovascular adjustment to situational requirements may be involved in the manifestation of bodily and mental symptoms.

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Integrating Breathing Techniques Into Psychotherapy to Improve HRV: Which Approach Is Best?

Frontiers in Psychology ◽

10.3389/fpsyg.2021.624254 ◽

2021 ◽

Vol 12 ◽

Author(s):

Patrick R. Steffen ◽

Derek Bartlett ◽

Rachel Marie Channell ◽

Katelyn Jackman ◽

Mikel Cressman ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Recovery Period ◽

Low Frequency ◽

Control Group ◽

Critical Writing ◽

Breathing Techniques ◽

Randomized Controlled Experiment ◽

Video Condition

IntroductionApproaches to improve heart rate variability and reduce stress such as breathing retraining are more frequently being integrated into psychotherapy but little research on their effectiveness has been done to date. Specifically, no studies to date have directly compared using a breathing pacer at 6 breaths per minute with compassion focused soothing rhythm breathing.Current StudyIn this randomized controlled experiment, 6 breaths per minute breathing using a pacer was compared with compassion focused soothing rhythm breathing, with a nature video being used as a control group condition.MethodsHeart rate variability (HRV) measures were assessed via electrocardiogram (ECG) and respiration belt, and an automated blood pressure machine was used to measure systolic diastolic blood pressure, and heart rate (HR). A total of 96 participants were randomized into the three conditions. Following a 5-min baseline, participants engaged in either 6 breath per minute breathing, soothing rhythm breathing, or watched a nature video for 10 min. To induce a stressful state, participants then wrote for 5 min about a time they felt intensely self-critical. Participants then wrote for 5 min about a time they felt self-compassionate, and the experiment ended with a 10-min recovery period.ResultsConditions did not significantly differ at baseline. Overall, HRV, as measured by standard deviation of NN intervals (SDNN), low frequency HRV (LF HRV), and LF/HF ratio, increased during the intervention period, decreased during self-critical writing, and then returned to baseline levels during the recovery period. High frequency HRV (HF HRV) was not impacted by any of the interventions. The participants in the 6 breath per minute pacer condition were unable to consistently breathe at that rate and averaged about 12 breaths per minute. Time by Condition analyses revealed that both the 6 breaths per minute pacer and soothing breathing rhythm conditions lead to significantly higher SDNN than the nature video condition during breathing practice but there were no significant differences between conditions in response to the self-critical and self-compassionate writing or recovery periods. The 6 breath per minute pacer condition demonstrated a higher LF HRV and LF/HF ratio than the soothing rhythm breathing condition, and both intervention conditions had a higher LF HRV and LF/HF ratio than the nature video.ConclusionsAlthough the 6 breath per minute pacer condition participants were not able to breath consistently at the low pace, both the participants attempting to breathe at 6 breaths per minute as well as those in the soothing rhythm breathing condition effectively increased HR variability as measured by SDNN, and attempting to breathe at 6 breaths per minute led to the highest LF HRV and LF/HF ratio. Both breathing approaches impacted HRV more than watching a relaxing nature video and can potentially be used as key adjuncts in psychotherapy to aid in regulating physiological functioning, although it appears that consistent breathing practice would be needed.

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Heart rate variability enhances the accuracy of non-invasive continuous blood pressure estimation under blood loss

Review of Scientific Instruments ◽

10.1063/5.0037661 ◽

2021 ◽

Vol 92 (10) ◽

pp. 105106

Author(s):

Guang Zhang ◽

Zongge Wang ◽

Feixiang Hou ◽

Zongming Wan ◽

Feng Chen ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Blood Loss ◽

Non Invasive ◽

Pressure Estimation ◽

Blood Pressure Estimation ◽

Continuous Blood Pressure

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The Effects of the Medical Pause on Physiological Stress Markers among Health Care Providers: A Pilot Randomized Controlled Trial

Western Journal of Nursing Research ◽

10.1177/01939459211027657 ◽

2021 ◽

pp. 019394592110276

Author(s):

Ebru Cayir ◽

Tim Cunningham ◽

Ryne Ackard ◽

Julie Haizlip ◽

Jeongok Logan ◽

...

Keyword(s):

Blood Pressure ◽

Health Care ◽

Heart Rate ◽

Heart Rate Variability ◽

Health Care Providers ◽

Physiological Stress ◽

Intervention Group ◽

Control Group ◽

Care Providers ◽

The Impact

Contemplative practices promote well-being, work engagement and resilience among health care providers. We examined the impact of The Pause, a brief contemplative intervention, on health care providers’ physiological stress response. Participants were randomly assigned to either The Pause or the control group. They participated in a high-fidelity, stressful medical simulation. Following the simulation, intervention group practiced The Pause. Outcome measures were heart rate variability, heart rate, and blood pressure. We adjusted for baseline physiological variables, sociodemographic variables, self-care practices, and perceived stress. Participants in the intervention group had a standard deviation of the normal-to-normal RR intervals (heart rate variability indicator) that was 13.8 (95% CI 4.0, 23.5; p < .01) points higher than those in the control group. There were no significant effects of The Pause on heart rate or blood pressure. The Pause may reduce stress reactivity, increase heart rate variability, and enhance resilience in health care providers.

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Effect of continuous infusion of dexmedetomidine on blood loss in orthognathic surgery: a retrospective study

European Journal of Medical Research ◽

10.1186/s40001-021-00551-5 ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Chenyu Jin ◽

Xiang Lv ◽

Yu Sun ◽

Hong Jiang

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Blood Loss ◽

Haemoglobin Level ◽

Continuous Infusion ◽

Orthognathic Surgery ◽

Operation Time ◽

Control Group ◽

Clinical Trial Registry ◽

Postoperative Haemoglobin

Abstract Background Patients with maxillofacial deformities require orthognathic surgeries to correct occlusion. The surgical procedure may lead to massive bleeding, which is associated with haematoma, respiratory obstruction, and asphyxia. Dexmedetomidine has been used in controlled hypotension and may reduce blood loss in orthognathic surgery. We conducted a retrospective cohort study to evaluate the effect of dexmedetomidine on blood loss in orthognathic surgeries. Methods The primary outcome examined was blood loss, and secondary outcomes were postoperative haemoglobin level; intraoperative heart rate and blood pressure (T1: at incision; T2: 30 min after incision; T3: 60 min after incision; T4: 120 min after incision); dosage of fentanyl, remifentanil, urapidil, and esmolol; operation time; and incidence of allogeneic blood transfusion. Results A total of 1247 patients were included in this study, and 540 patient pairs were matched via propensity score matching. There were significant decreases in mean blood loss, heart rate at T1–T4, blood pressure at T1, and remifentanil and esmolol dosage in the dexmedetomidine group compared with those in the control group. There was also a significant increase in the postoperative haemoglobin level of the dexmedetomidine group. Conclusions Continuous infusion of dexmedetomidine can decrease blood loss in orthognathic surgery. Trial registration: ChiCTR1800018794 (retrospectively registered) Name of registry: Chinese Clinical Trial Registry Date of registration: 2018/10/09 URL: www.chictr.org.cn/showproj.aspx?proj=30612

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Effect of Losartan and Atenolol on heart rate variability in newly diagnosed essential hypertensive patient

Bangabandhu Sheikh Mujib Medical University Journal ◽

10.3329/bsmmuj.v6i2.29135 ◽

2016 ◽

Vol 6 (2) ◽

pp. 161

Author(s):

Shamima Sultana ◽

Shelina Begum ◽

Sultana Ferdousi

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Essential Hypertension ◽

Antihypertensive Drugs ◽

Control Group ◽

Newly Diagnosed ◽

Hypertensive Patients ◽

Group B ◽

Mean Heart Rate

Background: Essential hypertension is associated with altered autonomic function. Essential hypertension is treated with drugs which modify the sympatho-parasympathetic balance. Losartan (angioteosin II receptor blocker) and atenolol (beta blocker) is commonly used antihypertensive drugs.Objective: To evaluate the effect of antihypertensive drugs on heart rate variability (HRV) in patients with essential hypertension.Methods: This prospective observational study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka from July 2012 to June 2013 on 120 newly diagnosed hypertensive patients without any medication (group B, age 30-55 years). They were selected from the Out Patients Department (OPD) of cardiology, BSMMU, Dhaka. Age, sex and BMI matched 60 apparently healthy norrnotensive subjects were also studied as control (group A). Based on treatment, these study subjects were divided into two groups (BI and B2). Group B1a included 60 patients received Josartan 50 mg daily and B2a included 60 patients received atenolol 50mg daily. They were observed once before the treatment (B1a & B2a), after 3 months medication (B1b & B2b) and after 6 months medication (B1c & B2c). For assessing HRV, Mean heart rate, Mean R-R interval, Max/Min R-R interval, SDNN, RMSSD were recorded by a polyrite. Data were compared among before treatment, after 3 months treatment and after 6 months treatment. For statistical analysis ANOVA, independent sample't' test and paired sample 't' test were performed. Results: Mean resting pulse rate, mean heart rate, systolic blood pressure, diastolic blood pressure were significantly higher and mean R-R interval, Max/Min R-R interval, SDNN, RMSSD were significantly lower in newly diagnosed hypertensive patients in comparison with that of healthy normotensive subjects and after treatment. Jn both groups SDNN, RMS SD, mean R-R interval were found significantly higher after 6 months of treatment compared to their values after 3 months treatment. Again these values were found close to the values in normotensive subjects. In addition, mean heart rate was found significantly lower in atenolol treated patients than those of controls. Again in atenolol group these values were found significanLly higher than the corresponding values in losartan treated patients after 6 months treatment. Conclusion: Reduced cardiac vagal tone occurs in newly diagnosed hypertensive patients which is improved by both losartan and atenolol and in particular atenolol was found more effective.

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