Head-up tilt and hemodynamic changes during orthostatic hypotension in patients with supine hypertension

The pathophysiology of orthostatic hypotension in Parkinson's disease (PD) is incompletely understood. The primary focus has thus far been on failure of the baroreflex, a central mediated vasoconstrictor mechanism. Here, we test the role of two other possible factors: 1) a reduced peripheral vasoconstriction (which may contribute because PD includes a generalized sympathetic denervation); and 2) an inadequate plasma volume (which may explain why plasma volume expansion can manage orthostatic hypotension in PD). We included 11 PD patients with orthostatic hypotension (PD + OH), 14 PD patients without orthostatic hypotension (PD − OH), and 15 age-matched healthy controls. Leg blood flow was examined using duplex ultrasound during 60° head-up tilt. Leg vascular resistance was calculated as the arterial-venous pressure gradient divided by blood flow. In a subset of 9 PD + OH, 9 PD − OH, and 8 controls, plasma volume was determined by indicator dilution method with radiolabeled albumin (125I-HSA). The basal leg vascular resistance was significantly lower in PD + OH (0.7 ± 0.3 mmHg·ml−1·min) compared with PD − OH (1.3 ± 0.6 mmHg·ml−1·min, P < 0.01) and controls (1.3 ± 0.5 mmHg·ml−1·min, P < 0.01). Leg vascular resistance increased significantly during 60° head-up tilt with no significant difference between the groups. Plasma volume was significantly larger in PD + OH (3,869 ± 265 ml) compared with PD − OH (3,123 ± 377 ml, P < 0.01) and controls (3,204 ± 537 ml, P < 0.01). These results indicate that PD + OH have a lower basal leg vascular resistance in combination with a larger plasma volume compared with PD − OH and controls. Despite the increase in leg vascular resistance during 60° head-up tilt, PD + OH are unable to maintain their blood pressure.

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Unobtrusive Detection of Simulated Orthostatic Hypotension and Supine Hypertension Using Ballistocardiogram and Electrocardiogram of Healthy Adults

IEEE Journal of Translational Engineering in Health and Medicine ◽

10.1109/jtehm.2018.2864738 ◽

2018 ◽

Vol 6 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Isaac S. Chang ◽

Narges Armanfard ◽

Abdul Q. Javaid ◽

Jennifer Boger ◽

Alex Mihailidis

Keyword(s):

Orthostatic Hypotension ◽

Healthy Adults ◽

Supine Hypertension

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Orthostatic Hemodynamic Changes in Brain Damage

General Reanimatology ◽

10.15360/1813-9779-2020-2-22-29 ◽

2020 ◽

Vol 16 (2) ◽

pp. 22-29

Author(s):

V. N. Dorogovtsev ◽

I. V. Molchanov ◽

D. S. Yankevich

Keyword(s):

Blood Pressure ◽

Brain Death ◽

Orthostatic Hypotension ◽

Brain Damage ◽

Disorders Of Consciousness ◽

Horizontal Position ◽

Hemodynamic Changes ◽

Short Period ◽

Chronic Disorders ◽

Chronic Disorders Of Consciousness

Aim: to study orthostatic hemodynamic changes in patients with chronic disorders of consciousness after critical brain damage.Materials and methods. We studied 30 patients (10 women and 20 men) with chronic disorders of consciousness after severe brain damage aged 45±7 years, 10 of which were in the vegetative state (VS) and 20 had the minimally conscious state (MCS). The main causes of brain damage were traumatic brain injury (53% of patients) and cerebrovascular accidents (CVA) (23.3%). The rest of the patients had posthypoxic encephalopathy or were after brain tumor removal surgery. Passive orthostatic test (POT) 0° to 60° to 0° was performed using an electrically driven tilt table (Vario Line). Hemodynamic monitoring during the verticalization was done using a non-invasive oscillometric recording of blood pressure on the brachial artery, stroke volume (SV) and cardiac minute output (CMO) were measured by impedance cardiography with the multifunctional «Task Force Monitor 3010i» (CNSystem, Austria). Data were statistically analyzed using the Statistica 10 software package.Results. Orthostatic hemodynamic stability was found in 26 out of 30 patients with chronic disorders of consciousness after critical brain damage. It was manifested by stable systolic blood pressure (SBP) in tilted orthostatic and horizontal position (120.7±2.2 and 121.1±3.6 mmHg, respectively, P>0.05). Orthostatic hypotension was observed in 3 patients and postural tachycardia syndrome (PTS) in one patient. We compared orthostatic hemodynamic changes in the studied cohort versus published data on orthostatic hemodynamic changes uncluding POT revealed in patients with severe brain damage examined before and after brain death.Conclusion. Orthostatic stability of blood circulation can be maintained for a short period of time in patients surviving after critical diffuse brain damage associated with chronic disorders of consciousness. Critical brain damage resulting in brain death associates with a significant reduction of all hemodynamic parameters and severe orthostatic hypotension with restoration of initial blood pressure values when the patient is returned to the horizontal position.

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603 CHALLENGES IN THE MANAGEMENT OF SEVERE ORTHOSTATIC HYPOTENSION ASSOCIATED WITH SUPINE HYPERTENSION IN A PATIENT WITH AUTONOMIC DYSFUNCTION ON BACKGROUND OF NASOPHARYNGEAL CARCINOMA AND TYPE II DIABETES MELLITUS

Age and Ageing ◽

10.1093/ageing/afab119.16 ◽

2021 ◽

Vol 50 (Supplement_2) ◽

pp. ii14-ii18

Author(s):

Q M N Rachel ◽

K Mamun ◽

M H Nguyen

Keyword(s):

Blood Pressure ◽

Nasopharyngeal Carcinoma ◽

Orthostatic Hypotension ◽

Carotid Sinus ◽

Blood Pressure Monitoring ◽

Pharmacological Interventions ◽

Supine Hypertension ◽

Neck Irradiation ◽

Baroreflex Failure

Abstract Introduction Combined chemotherapy and radiotherapy increases long term survival in patients with nasopharyngeal carcinoma. However, radiotherapy of the carotid sinus or brain stem can evolve labile hypertension and orthostatic intolerance from chronic baroreflex failure. Diabetes would also cause this neuropathy. Management of patients with Supine hypertension-Orthostatic hypotension can be very challenging. Methods A case report was done on a 71-year-old man with metastatic nasopharyngeal carcinoma status post radiation therapy who was admitted with severe supine hypertension-orthostatic hypotension. Patient was managed with both non-pharmacological and pharmacological methods, and monitored for postural symptoms, complications of severe supine hypertension—which has been linked to left ventricular hypertrophy and kidney dysfunction, and placed on 24 hour ambulatory blood pressure monitoring to aid in management so as to prevent hypertension induced organ damage. Results This review outlines the pathophysiology of Supine hypertension-Orthostatic hypotension, treatment complications and potential management strategies recommendations for this group of patients. It revealed the benefit of having a 24 hour ambulatory blood pressure monitoring, which provides insight on the timing and magnitude of an individual’s blood pressure fluctuations throughout the day so as to further guide management. Conclusion Chronic baroreflex failure is a late sequela of neck irradiation for naso-pharyngeal carcinoma due to accelerated atherosclerosis in the region of the carotid sinus baroreceptor. Treatment goal is achieved with adequate control of pre-syncopal symptoms and prevention of long term complications. Non-pharmacological interventions remain the first line of therapy, followed by pharmacological interventions as necessary. Nonetheless, management of blood pressure in these elderly patients with baroreflex dysfunction remains challenging and should be individualized. Moving forward, a prospective study on the incidence of late onset, iatrogenic baroreflex failure as a late complication of neck irradiation and its particular relationship to carotid arterial rigidity should be conducted to increase awareness, timely diagnosis and management of the condition among physicians.

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Performance evaluation of a portable bioimpedance cardiac output monitor for measuring hemodynamic changes in athletes during a head-up tilt test

Journal of Applied Physiology ◽

10.1152/japplphysiol.00822.2019 ◽

2020 ◽

Vol 128 (5) ◽

pp. 1146-1152

Author(s):

Cara H. Y. Cheung ◽

May L. Khaw ◽

Victor C. W. Tam ◽

Michael T. C. Ying ◽

Shara W. Y. Lee

Keyword(s):

Impedance Cardiography ◽

Tilt Test ◽

Physiological Changes ◽

Hemodynamic Changes ◽

Volume Measurements ◽

Head Up Tilt ◽

Gravitational Influence ◽

Cardiac Output Monitor ◽

Head Up Tilt Test ◽

Physical Features

The use of impedance cardiography to monitor physiological changes in sports is rarely reported. Using head-up tilt test, we evaluated a portable noninvasive impedance cardiography device (PhysioFlow) by comparing it with a reference Doppler monitor (USCOM). Accuracy in tracking hemodynamic changes deteriorated with higher tilt, implying a gravitational influence on its performance. Stroke volume measurements were overestimated, but the changes were underestimated. Despite its convenient physical features, the suitability of PhysioFlow for sports use is questionable.

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Standing and Supine Blood Pressure Outcomes Associated With Droxidopa and Midodrine in Patients With Neurogenic Orthostatic Hypotension: A Bayesian Meta-analysis and Mixed Treatment Comparison of Randomized Trials

Annals of Pharmacotherapy ◽

10.1177/1060028018786954 ◽

2018 ◽

Vol 52 (12) ◽

pp. 1182-1194 ◽

Cited By ~ 7

Author(s):

Jack J. Chen ◽

Yi Han ◽

Jonathan Tang ◽

Ivan Portillo ◽

Robert A. Hauser ◽

...

Keyword(s):

Blood Pressure ◽

Orthostatic Hypotension ◽

Fixed Effects ◽

Randomized Trials ◽

Meta Analysis ◽

Mixed Treatment Comparison ◽

Neurogenic Orthostatic Hypotension ◽

Supine Hypertension ◽

Treatment Comparison ◽

Mixed Treatment

Background: The comparative effects of droxidopa and midodrine on standing systolic blood pressure (sSBP) and risk of supine hypertension in patients with neurogenic orthostatic hypotension (NOH) are unknown. Objective: To perform a Bayesian mixed-treatment comparison meta-analysis of droxidopa and midodrine in the treatment of NOH. Methods: The PubMed, CENTRAL, and EMBASE databases were searched up to November 16, 2016. Study selection consisted of randomized trials comparing droxidopa or midodrine with placebo and reporting on changes in sSBP and supine hypertension events. Data were pooled to perform a comparison among interventions in a Bayesian fixed-effects model using vague priors and Markov chain Monte Carlo simulation with Gibbs sampling, calculating pooled mean changes in sSBP and risk ratios (RRs) for supine hypertension with associated 95% credible intervals (CrIs). Results: Six studies (4 administering droxidopa and 2 administering midodrine) enrolling a total of 783 patients were included for analysis. The mean change from baseline in sSBP was significantly greater for both drugs when compared with placebo (droxidopa 6.2 mm Hg [95% CrI = 2.4-10] and midodrine 17 mm Hg [95% CrI = 11.4-23]). Comparative analysis revealed a significant credible difference between droxidopa and midodrine. The RR for supine hypertension was significantly greater for midodrine, but not droxidopa, when compared with placebo (droxidopa RR = 1.4 [95% CrI = 0.7-2.7] and midodrine RR = 5.1 [95% CrI = 1.6-24]). Conclusion and Relevance: In patients with NOH, both droxidopa and midodrine significantly increase sSBP, the latter to a greater extent. However, midodrine, but not droxidopa, significantly increases risk of supine hypertension.

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