Defective Reflex Control of Heart Rate in Dialysis Patients: Evidence for an Afferent Autonomic Lesion

1982 ◽  
Vol 63 (3) ◽  
pp. 285-292 ◽  
Author(s):  
C. Zoccali ◽  
M. Ciccarelli ◽  
Q. Maggiore

1. To localize the site of autonomic abnormality in patients undergoing haemodialysis, tests of overall autonomic function based on either changes in blood pressure (posture, sustained handgrip) or heart rate (Valsalva manoeuvre, 30:15 ratio, deep breathing test) were used. Integrity of the sympathetic efferent arc was examined by using the cold pressor test and the parasympathetic efferent arc by the atropine test. Eighteen patients and 12 control subjects were studied. 2. Changes in blood pressure on standing, sustained handgrip and in the cold pressor test were the same in the two groups. 3. In contrast, 11 patients had abnormal results in at least two of the three heart-rate-based tests. 4. Three of the 11 dialysis patients with evidence of autonomic involvement showed abnormal responses to atropine, indicating an efferent parasympathetic lesion, whereas the majority had a normal response to the atropine test, suggesting an afferent lesion only. 5. Evidence of autonomic involvement was not associated with hypertension nor confined to patients with dialysis hypotension.

1985 ◽  
Vol 69 (5) ◽  
pp. 533-540 ◽  
Author(s):  
Gianfranco Parati ◽  
Guido Pomidossi ◽  
Agustin Ramirez ◽  
Bruno Cesana ◽  
Giuseppe Mancia

1. In man evaluation of neural cardiovascular regulation makes use of a variety of tests which address the excitatory and reflex inhibitory neural influences that control circulation. Because interpretation of these tests is largely based on the magnitude of the elicited haemodynamic responses, their reproducibility in any given subject is critical. 2. In 39 subjects with continuous blood pressure (intra-arterial catheter) and heart rate monitoring we measured (i) the blood pressure and heart rate rises during hand-grip and cold-pressor test, (ii) the heart rate changes occurring during baroreceptor stimulation and deactivation by injection of phenylephrine and trinitroglycerine, and (iii) the heart rate and blood pressure changes occurring with alteration in carotid baroreceptor activity by a neck chamber. Each test was carefully standardized and performed at 30 min intervals for a total of six times in each subject. 3. The results showed that the responses to any test were clearly different from one another and that this occurred in all subjects studied. For the group as a whole the average response variability (coefficient of variation) ranged from 10.2% for the blood pressure response to carotid baroreceptor stimulation to 44.2% for the heart rate response to cold-pressor test. The variability of the responses was not related to basal blood pressure or heart rate, nor to the temporal sequence of the test performance. 4. Thus tests employed for studying neural cardiovascular control in man produce responses whose reproducibility is limited. This phenomenon may make it more difficult to define the response magnitude typical of each subject, as well as its comparison in different conditions and diseases.


1993 ◽  
Vol 3 (5) ◽  
pp. 303-310 ◽  
Author(s):  
Frank Weise ◽  
Dominique Laude ◽  
Arlette Girard ◽  
Philippe Zitoun ◽  
Jean-Philippe Siché ◽  
...  

10.4085/16-20 ◽  
2020 ◽  
Author(s):  
Lentini Matylda ◽  
Scalia Joseph ◽  
Berger Lebel Frédérike ◽  
Touma Fadi ◽  
Jhajj Aneet ◽  
...  

Abstract Context: Athletes are often exposed to pain due to injury and competition. There is preliminary evidence that cardiovascular measures could be an objective measure of pain, but the cardiovascular response can be influenced by psychological factors such as catastrophizing. Objectives: The purpose of our study was to use a painful cold pressor test to measure the relationship between catastrophizing, pain, and cardiovascular variables in athletes. Design: Pre-post test. Setting: We completed all measures in a laboratory setting. Participants: Thirty-six male rugby athletes participated in the study. Main outcome measures: We measured catastrophizing with the Pain Catastrophizing Scale and pain with a Numeric Pain Rating Scale. Cardiovascular measures included heart rate, systolic, and diastolic blood pressure, and heart rate variability. Results: During the cold pressor test, participants experienced a significant increase in pain (0 to 4.1±2.2), systolic blood pressure (126.7±16.5mm Hg to 149.7±23.4mm Hg), diastolic blood pressure (76.9±8.3mm Hg to 91.9±11.5mm Hg) and heart rate variability (from 0.0164ms±0.0121 to 0.0400ms±0.0323) (all p<.001). In addition, there was a significant decrease in heart rate after the cold pressor test (p=0.04). There was a significant correlation between athlete's pain catastrophizing to both pain intensity and change in heart rate during the cold pressor test (p=.017 and p=.003 respectively). A significant linear regression indicated pain and catastrophizing explained 29% of the variance of the change in heart rate (p=.003). Conclusion: Athletes who have catastrophizing thoughts are more likely to experience higher levels of pain and a greater cardiovascular response during a painful stimulus. The change in cardiovascular variables may be a good alternative for an objective measure of pain in athletes in the future.


2015 ◽  
Vol 1 (7) ◽  
pp. 293
Author(s):  
Mohit Malge ◽  
K. Ranjith Babu

Introduction: Smoking is one of the most ancient and widespread mans activities. The present study was chosen to determine sympathetic and parasympathetic activity in cigarette smokers and compare it with healthy age matched controls in order to find out what influence does smoking have on baroreceptor sympathetic and parasympathetic control mechanisms and to find out for any co-relation between duration of cigarette smoking and autonomic dysfunction.Materials & Methods: Fifty cigarette smokers and fifty normal, healthy, nonsmokers were selected as age matched controls to study autonomic functions. Sympathetic functions were carried out by Cold Pressor Response test and Hand Grip test. Parasympathetic functions were tested by Determination of Heart Rate with change in posture and Sinus Arrhythmia.Results: Smokers revealed more pronounced rise both in systolic as well as diastolic blood pressure as compared to normal healthy controls during cold pressor test. Smokers revealed more pronounced rise in both SBP and DBP as compared to nonsmokers during hand grip test. There was increased heart rate in initial 10 seconds when there is postural change i.e. lying down to standing in both the groups. There was an increase in heart rate during inspiration and decrease during expiration (sinus arrhythmia) both in smokers and healthy controls.Conclusion: Cigarette smoking affects cardiovascular functions as indicated by rise in blood pressure in smokers than nonsmokers reflects the sensitivity of sympathetic activity to nicotine due to smoking. Thus the study concludes that smoking possibly has an effect on neurocardiovascular regulation system altering the sensitivity of ANS activity in habitual smokers.Keywords: Autonomic Function Tests, Smokers, Non-smokers, Cold Pressor Test, Hand Grip Test, Heart Rate.


1985 ◽  
Vol 68 (1) ◽  
pp. 49-56 ◽  
Author(s):  
B. C. Campbell ◽  
Alessandra Sturani ◽  
J. L. Reid

1. Captopril (50 mg orally) produced a significant fall in systolic and diastolic blood pressure in six normotensive sodium replete subjects, without a rise in heart rate. 2. On captopril, there was no change in the expected normal increase in heart rate on standing. Supine plasma noradrenaline was not reduced by captopril and normal postural increases were maintained. 3. Atropine (0.04 mg/kg i.v.) reduced the difference in blood pressure change between captopril and placebo. 4. Facial immersion in water produced a bradycardia. This change was abolished by atropine and attenuated both by captopril and edrophonium (10 mg i.V.), a cholinesterase inhibitor. 5. Lying down after 6 min standing produced an immediate transient tachycardia, which was abolished by atropine and attenuated by captopril. 6. Blood pressure and heart rate rose after a cold pressor test on both captopril and placebo. 7. The tachycardia during the Valsalva manoeuvre was inhibited by edrophonium and to a lesser extent by captopril. The effects of captopril and edrophonium were additive. 8. Parasympathetic activity of captopril may contribute to its haemodynamic profile.


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