Cardiovascular and Autonomic Reflexes in Haemodialysis Patients

1981 ◽  
Vol 60 (2) ◽  
pp. 165-170 ◽  
Author(s):  
R. B. Naik ◽  
C. J. Mathias ◽  
C. A. Wilson ◽  
J. L. Reid ◽  
D. J. Warren
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Plasma Noradrenaline ◽  
Valsalva Manoeuvre ◽  
Induced Hypotension ◽  
Autonomic Nervous ◽  
Control Subjects ◽  
Head Up Tilt ◽  
And Control ◽  
Noradrenaline Levels

1. Blood pressure and heart rate responses to head-up tilt, standing, the Valsalva manoeuvre, sustained handgrip and cutaneous cold were measured in 27 haemodialysis patients (10 of whom had episodes of haemodialysis-induced hypotension) and 15 control subjects to assess autonomic nervous function. Plasma nor-adrenaline levels were measured at rest and during head-up tilt. 2. Mean resting supine blood pressure, heart rate and plasma noradrenaline levels were higher in haemodialysis patients than in the control subjects. There was no fall in blood pressure during head-up tilt or standing. The ratio of the R-R intervals of the thirtieth and the fifteenth heart beat after standing (30: 15) was lower in the patients; this may be related to their higher resting heart rate. Head-up tilt raised plasma noradrenaline levels in both groups. Heart rate responses to the Valsalva manoeuvre were similar in the patients and control subjects. 3. Systolic blood pressure and heart rate responses to sustained handgrip were similar in both groups. Diastolic and mean blood pressure changes, however, were lower in the patients. The blood pressure and heart rate responses to cutaneous cold were similar in the patients and control subjects. 4. We conclude that generalized autonomic nervous dysfunction does not appear to cause haemodialysis-induced hypotension in patients with chronic renal failure on maintenance haemodialysis.

Relation of Plasma Noradrenaline to Blood Pressure, Age, Sex and Sodium Balance in Patients with Stable Essential Hypertension and in Normotensive Subjects

1978 ◽  
Vol 55 (s4) ◽  
pp. 81s-83s ◽  
Author(s):  
H. M. Brecht ◽  
W. Schoeppe
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Essential Hypertension ◽  
Diastolic Blood Pressure ◽  
Plasma Noradrenaline ◽  
Sodium Balance ◽  
Creatinine Ratio ◽  
Control Subjects ◽  
Normotensive Subjects ◽  
Normotensive Control

1. Plasma noradrenaline was measured in 125 patients with stable essential hypertension (WHO I—II) and in 107 normotensive control subjects lying and standing. 2. In normotensive subjects and in patients with essential hypertension no sex-related differences of plasma noradrenaline were found between age-matched groups. 3. Plasma noradrenaline was not related to sodium balance indexed by urinary sodium/creatinine ratio. 4. In patients with essential hypertension plasma noradrenaline increases with age. 5. Mean plasma noradrenaline concentrations are significantly higher in patients with essential hypertension compared with age-matched normotensive subjects both lying and standing. 6. In patients with essential hypertension diastolic blood pressure and heart rate correlated significantly with supine plasma noradrenaline concentrations.

Plasma Noradrenaline as a Measure of Baroreflex Sensitivity in Hypertensive Man

1981 ◽  
Vol 61 (s7) ◽  
pp. 165s-168s ◽  
Author(s):  
A. M. M. Shepherd ◽  
M.-S. Lin ◽  
T. K. Keeton ◽  
J. L. McNay
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Baroreflex Sensitivity ◽  
Clinical Investigation ◽  
Plasma Noradrenaline ◽  
Chronotropic Response ◽  
Plasma Noradrenaline Concentration ◽  
Noradrenaline Concentration ◽  
Lower Blood ◽  
Noradrenaline Levels

1. Changes in plasma noradrenaline levels and heart rate were used as measures of baroreflex sensitivity in six hypertensive subjects given serial incremental doses of sodium nitroprusside (intravenously) to lower blood pressure. 2. The rises in both heart rate and plasma noradrenaline concentration were linearly related to the decrement in blood pressure and inversely related to the severity of the hypertension. 3. A positive correlation between rise in heart rate and rise in plasma noradrenaline was found for each subject. With increasing severity of hypertension, a greater increase in heart rate occurred for each increment in plasma noradrenaline concentration. 4. Baroreflex sensitivity can be assessed by relating changes in heart rate to change in arterial pressure; however, this method does not distinguish the relative contributions of the vagal and sympathetic components of the autonomic neural response or variations in the chronotropic response to sympathetic stimulation. 5. Changes in plasma noradrenaline levels in response to graded reductions in blood pressure may be a more appropriate measure of baroreflex sensitivity than the methods currently used in clinical investigation.

Afferent baroreflex dysfunction and age-related orthostatic hypotension

1991 ◽  
Vol 81 (s25) ◽  
pp. 531-538 ◽  
Author(s):  
A. L. Tonkin ◽  
L. M. H. Wing ◽  
M. J. Morris ◽  
V. Kapoor
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cold Stress ◽  
Orthostatic Hypotension ◽  
Autonomic Neuropathy ◽  
Isometric Exercise ◽  
Control Subjects ◽  
Age Related ◽  
Head Up Tilt ◽  
Elderly Control

1. To test the hypothesis that in apparently healthy elderly subjects with orthostatic hypotension there is afferent baroreflex dysfunction, cardiovascular and neurohumoral responses were measured after separate stimuli which activated baroreceptor (head-up tilt) and non-baroreceptor (cold stress, isometric exercise) afferent pathways. 2. In 15 healthy elderly control subjects blood pressure did not change with 60° head-up tilting and there was a moderate increase in heart rate, whereas in 13 subjects with age-related orthostatic hypotension head-up tilting was associated with a marked fall in blood pressure but a similar heart rate response to that in the elderly control group. In contrast, both groups of subjects had similar blood pressure and heart rate responses to cold stress and sustained isometric exercise. 3. Nine subjects with autonomic neuropathy also showed a marked hypotensive response to head-up tilt, but produced no pressor response to cold stress or isometric exercise. 4. The plasma concentrations of noradrenaline, adrenaline and neuropeptide-Y-like immunoreactivity rose and that of atrial natriuretic peptide fell after head-up tilt in the study population as a whole. There were no significant differences between groups despite the much greater blood pressure drops in the subjects with autonomic neuropathy and in those with age-associated orthostatic hypotension. 5. The aorto-iliac pulse wave velocity index was significantly higher in subjects with age-associated orthostatic hypotension compared with that in control subjects. 6. The pattern of responses to the separate stresses observed in the group with age-associated orthostatic hypotension is characteristic and different from that in the elderly control subjects and the subjects with autonomic neuropathy. It suggests that age-associated orthostatic hypotension is related predominantly to dysfunction in the afferent limb of the baroreflex arc, possibly partially caused by a splinting of arterial baroreceptors by non-compliant arterial walls.

Endogenous Opioids Modulate Central Nervous System Blood Pressure Control in Man

1982 ◽  
Vol 63 (s8) ◽  
pp. 331s-333s ◽  
Author(s):  
P. C. Rubin ◽  
Kathleen McLean ◽  
J. L. Reid
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Pressure Control ◽  
Normal Subjects ◽  
Pressure Control ◽  
Endogenous Opioids ◽  
Plasma Noradrenaline ◽  
Head Up Tilt ◽  
Blind Manner

1. Two studies were performed to elucidate the role of opioids in blood pressure control in man. 2. Study 1: nine normal subjects, 18–32 years, received in a randomized single blind manner, volume matched infusions of a Met-enkephalin analogue (DAMME) 0.5 mg, naloxone 0.2 mg/kg or saline. Blood pressure, heart rate and plasma noradrenaline were determined supine and after a 5 min, 70° head-up tilt at 0, 3/4, 2, 3, 4, 5 and 6 h. 3. Study 2: seven subjects, after baseline recordings of blood pressure and heart rate received six incremental infusions of sodium nitroprusside, 1.5–7.5 μg min−1 kg−1. They then received DAMME or naloxone and the nitroprusside infusions were repeated between 3 and 4 h. There was a significant linear relationship between fall in mean arterial pressure and rise in heart rate in each case and the slope was used as an index of baroreflex sensitivity. 4. Neither naloxone nor DAMME influenced supine blood pressure or heart rate. Blood pressure after head-up tilt was significantly (analysis of variance) decreased by DAMME for up to 5 h but not by naloxone, the effect being most marked at 3 h: systolic (mean ± sd), placebo 110 ± 6, naloxone 106 ± 10, DAMME 96 ± 16 (P< 0.02); diastolic (mean ± sd), placebo 78 ± 7, naloxone 79 ± 5, DAMME 67 ± 8 (P < 0.01). The increases in heart rate and plasma noradrenaline on tilting after DAMME were not significantly different from values with placebo or naloxone. The 3 h values for heart rate were: placebo 87 ± 16, naloxone 88 ± 19, DAMME 89 ± 23 (P > 0.1); for plasma noradrenaline (nmol/l): placebo 6.0 ± 2.2, naloxone 5.8 ± 1.9, DAMME 6.0 ± 1.9 (P > 0.1). 5. Naloxone significantly increased the slope (beats per min/mmHg) of the regression relationship from a mean of 1.8 ± 0.07 to 3.0 ± 1.3 (P < 0.05), and DAMME reduced the slope from 2.7 ± 1.7 to 1.2 ± 0.5 (P < 0.05). 6. We conclude that endogenous opioids modulate baroreflex function in man.

Short-term variability of blood pressure and heart rate in Guillain-Barreá syndrome without respiratory failure

1999 ◽  
Vol 96 (6) ◽  
pp. 613-621 ◽  
Author(s):  
Djillali ANNANE ◽  
Véronique BAUDRIE ◽  
Anne-Sophie BLANC ◽  
Dominique LAUDE ◽  
Jean-Claude RAPHAËL ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Respiratory Failure ◽  
Plasma Noradrenaline ◽  
Heart Period ◽  
Short Term ◽  
Heart Period Variability ◽  
Period Variability ◽  
Head Up Tilt ◽  
Short Term Variability

The effect of Guillain-Barré syndrome (GBS) on the short-term variability of blood pressure and heart rate was evaluated in six patients presenting with a moderate form of the syndrome, i.e. unable to stand up unaided and without respiratory failure, at the height of the disease and during recovery. The patients were compared with six age-matched healthy volunteers. During the acute phase of the syndrome, GBS patients exhibited a significant heart rate elevation (+26 beats/min compared with healthy subjects), but the acceleratory response to atropine, or to 60 ° head-up tilt, was maintained. Resting plasma noradrenaline levels were high in acute GBS, but the secretory response to tilt was preserved. Desensitization to noradrenaline was observed in acute GBS with a reduced pressor action of this α-adrenoceptor agonist. Blood pressure levels were normal and head-up tilt did not induce orthostatic hypotension in this moderate form of GBS. Power spectral analysis demonstrated marked alterations in cardiovascular variability. The overall heart period variability was markedly reduced with the reduction predominantly in the high-frequency (respiratory) range (-73%). The low-frequency component of heart period variability was also reduced (-54%). This cardiovascular profile of moderate GBS at the height of the disease could result from a demyelination of the reflex loop controlling respiratory oscillations in heart rate and from a desensitization of the arterial tree to an elevated plasma noradrenaline. Sympathetic nervous activation may contribute to the high resting heart rate in acute GBS.

Short- and long-term reproducibility of autonomic measures in supine and standing positions

2004 ◽  
Vol 106 (1) ◽  
pp. 61-66 ◽  
Author(s):  
M. A. KOWALEWSKI ◽  
M. URBAN
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Response ◽  
Blood Pressure Response ◽  
Body Position ◽  
Valsalva Manoeuvre ◽  
Deep Breathing ◽  
Autonomic Nervous ◽  
Short And Long Term

Autonomic nervous tests and heart rate variability (HRV) have been used to assess cardiac autonomic function and to evaluate long-term prognosis. The aim of this study was to evaluate the short- and long-term reproducibility of HRV parameters and autonomic nervous tests according to body position (supine or standing). The study group consisted of 26 healthy subjects. Autonomic nervous tests and HRV were performed twice during the day and the results were averaged. The protocol was then repeated 3 days after each examination and also after 6 and 24 months. Autonomic nervous tests included deep breathing, Valsalva manoeuvre and isometric muscle exercise (handgrip), as well as blood pressure and heart rate in response to standing. ECG recordings were taken for 10 min during spontaneous breathing for HRV analysis. We found that the reproducibility of some parameters of the autonomic nervous test were independent of body position [E/I ratio (heart rate response to deep breathing)], whereas other parameters were dependent on body position (Valsalva manoeuvre and blood pressure response to sustained handgrip). In addition, within-day measurements of those parameters varied from non-reproducible (Valsalva ratio, handgrip and blood pressure response to standing) to moderately reproducible [E/I ratio and 30/15 ratio (heart rate response to standing)]. Among the HRV parameters, we found that total power (TP), low (LF)- and high (HF)-frequency were reproducible not only for measurements made within the same day, but also during short- and long-term observations, and only the LF/HF ratio was dependent on body position. We conclude that only a few autonomic nervous tests are reproducible in the short- and long-term. Because HRV parameters obtained during spontaneous respiration showed high reproducibility for measurements made within the same day as well as in the short- and long-term, they should be used instead of autonomic nervous tests when long-term observations are carried out in a healthy population.

Changes in plasma free 3,4-dihydroxyphenylethylene glycol and noradrenaline levels after acute alcohol administration

1985 ◽  
Vol 69 (4) ◽  
pp. 423-428 ◽  
Author(s):  
L. G. Howes ◽  
J. L. Reid
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Major Effect ◽  
Plasma Noradrenaline ◽  
Normal Male ◽  
Alcohol Administration ◽  
Reflex Tachycardia ◽  
Transient Rise ◽  
Blood Pressures ◽  
Noradrenaline Levels

1. The effects of alcohol (0.9 g/kg) compared with placebo (400 ml of orange juice) on plasma noradrenaline and 3,4-dihydroxyphenylethylene glycol levels, and on erect and supine blood pressures and heart rates, were studied in eight normal male volunteers. 2. Alcohol caused a rise in noradrenaline levels that commenced approximately 30 min after drinking and lasted about 4h. In contrast, 3,4-dihydroxyphenylethylene glycol levels fell immediately after alcohol administration and remained low for at least 6h. Acute alcohol administration alters noradrenaline catabolism, and may have a dual effect of increasing noradrenaline release and decreasing noradrenaline clearance. 3. Alcohol caused a transient rise in erect and supine blood pressures that preceded the rise in plasma noradrenaline. Thereafter erect blood pressures fell compared with control. This fall was associated with a progressive rise in both supine and erect rates, and reached a maximum several hours after the maximum levels of blood alcohol. 4. The major effect of acute alcohol administration is to lower blood pressure and induce a reflex tachycardia. Changes in noradrenaline and 3,4-dihydroxyphenylethylene glycol levels did not readily explain changes in blood pressure or heart rate, suggesting that alcohol induced changes in noradrenaline metabolism occur largely independent of changes in blood pressure and heart rate.

Compression Stocking Length Effects on Arterial Blood Pressure and Heart Rate Following Head-Up Tilt in Healthy Volunteers

2014 ◽  
Vol 63 (6) ◽  
pp. 435-438 ◽  
Author(s):  
Kunihiko Tanaka ◽  
Shiori Tokumiya ◽  
Yumiko Ishihara ◽  
Yumiko Kohira ◽  
Tetsuro Katafuchi
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Healthy Volunteers ◽  
Arterial Blood Pressure ◽  
Compression Stocking ◽  
Arterial Blood ◽  
Head Up Tilt ◽  
Length Effects
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