Haemodynamic and Neurohumoral Effects of Caffeine in Elderly Patients with Symptomatic Postprandial Hypotension: A Double-Blind, Randomized, Placebo-Controlled Study

1994 ◽  
Vol 87 (2) ◽  
pp. 259-267 ◽  
Author(s):  
Lewis A. Lipsitz ◽  
Rene W. M. M. Jansen ◽  
Carolyn M. Connelly ◽  
Margaret M. Kelley-Gagnon ◽  
Anthony J. Parker
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Elderly Patients ◽  
Blood Volume ◽  
Vascular Resistance ◽  
Controlled Study ◽  
Pathophysiological Mechanism ◽  
Double Blind ◽  
Postprandial Hypotension ◽  
Forearm Vascular Resistance

1. The aim of this study was to determine the effects of caffeine on haemodynamic and neurohumoral responses to meal ingestion in elderly patients with a history of symptomatic postprandial hypotension. 2. Postprandial hypotension is a common disorder of blood pressure regulation in the elderly, associated with falls and syncope. The pathophysiological mechanism is thought to be related to impaired vascular compensation for splanchnic blood pooling after a meal. Since caffeine inhibits vasodilatory adenosine receptors in the splanchnic circulation, we postulated that caffeine would reduce splanchnic blood pooling and prevent the development of postprandial hypotension. 3. We conducted a randomized, double-blind, placebo-controlled, cross-over study in nine elderly patients [age 76 ± 9 (SD) years] with histories of symptomatic postprandial hypotension. Standardized 1674 kJ liquid meals with 250 mg of caffeine or placebo were given on two occasions, at least 1 week apart. Blood pressure, heart rate, forearm vascular resistance (by venous occlusion plethysmography), and plasma caffeine and catecholamine levels were measured. Cardiac and splanchnic blood volume were determined by radionuclide scans. 4. By 30 min after both caffeine and placebo meal studies, supine mean arterial blood pressure fell significantly (P = 0.006) by 31 ± 7 and 19 ± 6 mmHg, respectively (mean ± SEM, between group difference was not significant). Heart rate, cardiac output and splanchnic blood volume increased significantly, but to a similar extent, after caffeine and placebo. Forearm vascular resistance was unchanged after both meals. 5. Oral caffeine given with a meal does not reduce splanchnic blood pooling nor prevent postprandial hypotension in symptomatic elderly patients.

scholarly journals Dexamethasone blunts postspinal hypotension in geriatric patients undergoing orthopedic surgery: a double blind, placebo-controlled study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Tarek M. Ashoor ◽  
Noha S. Hussien ◽  
Sherif G. Anis ◽  
Ibrahim M. Esmat
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Elderly Patients ◽  
Spinal Anesthesia ◽  
Demographic Data ◽  
Volume Overload ◽  
Controlled Study ◽  
Hyperbaric Bupivacaine ◽  
Double Blind ◽  
Link Type

Abstract Background Post-spinal anesthesia (PSA) hypotension in elderly patients is challenging. Correction of PSA hypotension by fluids either colloids or crystalloids or by vasoconstrictors pose the risk of volume overload or compromising cardiac conditions. Dexamethasone is used to treat conditions manifested by decrease of peripheral vascular resistance. The research team was the first to test the hypothesis of its role in preventing or decreasing the incidence of PSA hypotension. Methods One hundred ten patients, aged 60 years or more were recruited to receive a single preoperative dose of dexamethasone 8 mg IVI in 100 ml normal saline (D group) (55 patients) 2 h preoperatively, and 55 patients were given placebo (C group) in a randomized, double-blind trial. Variations in blood pressure and heart rate in addition to the needs of ephedrine and/or atropine following spinal anesthesia (SA) were recorded. SA was achieved using subarachnoid injection of 3 ml hyperbaric bupivacaine 0.5%. Results Demographic data and the quality of sensory and motor block were comparable between groups. At 5th, 10th minutes post SA; systolic, diastolic and mean arterial pressures were statistically significant higher in D group. At 20th minutes post SA; the obtained blood pressure readings and heart rate changes didn’t show any statistically significance between groups. The need for ephedrine and side effects were statistically significant lower in D group than C group. Conclusion Post-spinal anesthesia hypotension, nausea, vomiting and shivering in elderly patients were less common after receiving a single preoperative dose of dexamethasone 8 mg IVI than control. Registration number ClinicalTrials.gov Identifier: NCT 03664037, Registered 17 September 2018 - Retrospectively registered, http://www.ClinicalTrial.gov

scholarly journals Dexamethasone blunts postspinal hypotension in geriatric patients undergoing orthopedic surgery: a double blind, placebo-controlled study

2021 ◽  
Author(s):  
Tarek Ashoor ◽  
Noha S. Hussien ◽  
Sherif G. Anis ◽  
Ibrahim M. Esmat
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Elderly Patients ◽  
Spinal Anesthesia ◽  
Demographic Data ◽  
Volume Overload ◽  
Controlled Study ◽  
Hyperbaric Bupivacaine ◽  
Double Blind

Abstract Background: Post-spinal anesthesia (PSA) hypotension in elderly patients is challenging. Correction of PSA hypotension by fluids either colloids or crystalloids or by vasoconstrictors pose the risk of volume overload or compromising cardiac conditions. Dexamethasone is used to treat conditions manifested by decrease of peripheral vascular resistance. The research team was the first to test the hypothesis of its role in preventing or decreasing the incidence of PSA hypotension.Methods: 110 patients, aged 60 years or more were recruited to receive a single preoperative dose of dexamethasone 8 mg IVI in 100 ml normal saline (D group) (55 patients) 2 hours preoperatively, and 55 patients were given placebo (C group) in a randomized, double-blind trial. Variations in blood pressure and heart rate in addition to the needs of ephedrine and/or atropine following spinal anesthesia (SA) were recorded. SA was achieved using subarachnoid injection of 3 ml hyperbaric bupivacaine 0.5%.Results: Demographic data and the quality of sensory and motor block were comparable between groups. At 5th, 10th minutes post SA; systolic, diastolic and mean arterial pressures were statistically significant higher in D group. At 20th minutes post SA; the obtained blood pressure readings and heart rate changes didn’t show any statistically significance between groups. The need for ephedrine and side effects were statistically significant lower in D group than C group. Conclusion: Post-spinal anesthesia hypotension, nausea, vomiting and shivering in elderly patients were less common after receiving a single preoperative dose of dexamethasone 8 mg IVI than control.

scholarly journals The Prophylactic Antiemetic Efficacy of Prochlorperazine and Ondansetron in Nasal Septal Surgery: A Randomized Double-Blind Comparison

1996 ◽  
Vol 24 (5) ◽  
pp. 538-545 ◽  
Author(s):  
A. A. Van Den Berg
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular Effects ◽  
Controlled Study ◽  
Postoperative Vomiting ◽  
Double Blind ◽  
Septal Surgery ◽  
Postoperative Headache ◽  
Per Se ◽  
Blind Comparison

A prospective, randomized placebo-controlled study was undertaken to compare the effects on heart rate and blood pressure during surgery and on the incidence of nausea, vomiting and headache after surgery of IM prochlorperazine 0.2 mg.kg-1, IV prochlorperazine 0.1 mg.kg-1 and IV ondansetron 0.06 mg.kg-1 given at induction of general anaesthesia to patients undergoing septorhinoplasty. The effects of the test drugs after administration on heart rate and blood pressure were similar, as were the incidences of retching and vomiting in the recovery ward after each test drug. Postoperatively, compared with placebo (7%), nausea per se was most frequent in those given IV prochlorperazine (25%, P<0.01), and less frequent in those given IM prochlorperazine (2%) and IV ondansetron (15%). Vomiting per se was reduced from 24% to 7% (P<0.025) by IV prochlorperazine and to 4% (P<0.0005) by IV ondansetron. The incidence of nausea with vomiting was reduced from 35% to 15% (P<0.025), 16% (P<0.05) and 11% (P<0.005) by IM prochlorperazine, IV prochlorperazine and IV ondansetron respectively. IM prochlorperazine and IV ondansetron increased the frequency (from 35% to 64%, P<0.0005 and to 71%, P<0.0005, respectively) of those experiencing no PONV and delayed the onset of PONV, but only IM prochlorperazine reduced the severity of postoperative vomiting. Headache was frequent in the control (69%), IV prochlorperazine (62%) and IV ondansetron (69%) groups, and least frequent after IM prochlorperazine (53%; P<0.05 versus IV ondansetron). It is concluded that these drugs have no adverse cardiovascular effects within 10 minutes of administration, IM prochlorperazine and IV ondansetron reduce PONV more effectively than IV prochlorperazine and postoperative headache after septorhinoplasty occurs less frequently in those given IM prochlorperazine than in those given IV ondansetron.

Cardiovascular reflex responses in Bangladeshi and European subjects

1991 ◽  
Vol 80 (1) ◽  
pp. 39-45 ◽  
Author(s):  
M. A. Rahman ◽  
I. Farquhar ◽  
T. Bennett
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systolic Blood Pressure ◽  
Vascular Resistance ◽  
Cardiovascular Responses ◽  
Mean Blood Pressure ◽  
Valsalva Manoeuvre ◽  
Deep Breathing ◽  
Reflex Responses ◽  
Forearm Vascular Resistance

1. Cardiovascular responses to three different interventions, namely the Valsalva manoeuvre, deep breathing and a cold stimulus on the face, were studied in two ethnic groups (European and Bangladeshi) that have been shown to differ in the prevalence of hypertensive-vascular disease. The data obtained consisted of systolic blood pressure, diastolic blood pressure, mean blood pressure, heart rate measured by using a beat-by-beat non-invasive blood pressure monitor (the Finapres), forearm blood flow determined by venous occlusion plethysmography, and calculated forearm vascular resistance. 2. The resting haemodynamic status was similar in European and Bangladeshi subjects. However, Bangladeshi subjects showed a greater increase in heart rate, but only after 20 s into the Valsalva manoeuvre, and greater overshoots in mean blood pressure after the manoeuvre than the European subjects. Furthermore, after cold face stimulation the fall in forearm vascular resistance to baseline levels was delayed in Bangladeshi subjects relative to that in the European subjects. 3. There were no inter-group differences in the reflex bradycardia relative to mean blood pressure or in the cardiac baroreflex sensitivity estimated from systolic blood pressure and pulse interval after the Valsalva manoeuvre. In addition, values for the mean difference between maximum and minimum pulse intervals during deep breathing did not differ in Bangladeshi and European subjects. 4. These findings together suggest that, although cardiac vagal reflex responses appear similar in the two groups, sympatho-adrenal influences on the heart and vasculature may be greater in Bangladeshi subjects than in European subjects.

Endogenous substance P modulates human cardiovascular regulation at rest and during orthostatic load

2007 ◽  
Vol 102 (6) ◽  
pp. 2092-2097 ◽  
Author(s):  
Matthew V. Dzurik ◽  
André Diedrich ◽  
Bonnie Black ◽  
Sachin Y. Paranjape ◽  
Satish R. Raj ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Substance P ◽  
Systemic Vascular Resistance ◽  
Vascular Resistance ◽  
Muscle Sympathetic Nerve Activity ◽  
Cardiovascular Regulation ◽  
Postural Adjustment ◽  
Compensatory Mechanisms ◽  
Double Blind

Substance P (SP) is a peptide neurotransmitter identified in many central and peripheral neural pathways. Its precise role in human physiology has been difficult to elucidate. We used the selective neurokinin 1 (NK1) antagonist aprepitant as a pharmacological probe to determine the role of endogenous SP in human cardiovascular regulation. We performed a randomized, double-blind, placebo-controlled, crossover trial in healthy subjects. Blockade of endogenous NK1 receptors reduced resting muscle sympathetic activity 38% ( P = 0.002), reduced systemic vascular resistance by 25% ( P = 0.021), and increased cardiac index by 47% ( P = 0.006). This constellation of changes did not, however, alter either blood pressure or heart rate in the supine position. NK1 antagonism also raised orthostatic heart rate change by 38% ( P = 0.023), although during the incremental postural adjustment on the tilt table neither heart rate nor blood pressure was altered significantly. Despite a mildly attenuated vagal baroreflex with SP blockade, the depressor and pressor responses to nitroprusside and phenylephrine did not differ compared with placebo, suggesting other compensatory mechanisms. NK1 blockade manifests as a decrease in muscle sympathetic nerve activity and systemic vascular resistance. Our study suggests SP exerts a tonic enhancement of sympathetic outflow to some cardiovascular structures via its modulation of the NK1 receptor. Most likely, this ubiquitous neurotransmitter exerts effects at multiple sites that, in the aggregate, are relatively well compensated under many circumstances but may emerge with perturbations. This study is consistent with a role for SP afferents in supporting peripheral vascular resistance.

Haemodynamic effects of physiological concentrations of circulating noradrenaline in man

1988 ◽  
Vol 75 (5) ◽  
pp. 469-475 ◽  
Author(s):  
Peter C. Chang ◽  
Eugene Kriek ◽  
Jacques A. Van Der Krogt ◽  
Gerard-Jan Blauw ◽  
Peter Van Brummelen
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Vascular Resistance ◽  
Forearm Blood Flow ◽  
Haemodynamic Effects ◽  
Plasma Noradrenaline ◽  
Arterial Blood ◽  
Forearm Vascular Resistance ◽  
Venous Plasma

1. To define the role of circulating noradrenaline in cardiovascular regulation, threshold concentrations for haemodynamic effects were determined in arterial and venous plasma of eight healthy volunteers. 2. Five doses of noradrenaline, 0–54 ng min−1 kg−1, were infused intravenously in random order and single-blind for 15 min per dose. Changes in intra-arterial blood pressure, heart rate, forearm blood flow and forearm vascular resistance were determined, and plasma noradrenaline was measured in arterial and venous blood samples. 3. Significant increases in systolic and diastolic blood pressure were found at arterial and venous plasma noradrenaline concentrations (means ±sem) of 3.00 ± 0.23 and 1.35 ±0.12 nmol/l, respectively. A significant decrease in heart rate was found at arterial and venous plasma noradrenaline concentrations of 8.99 ± 0.69 and 3.09 ± 0.60 nmol/l, respectively. The lower doses of noradrenaline tended to increase forearm blood flow and to decrease forearm vascular resistance, whereas the higher doses had no consistent effect on forearm haemodynamics. 4. During the noradrenaline infusions 73 ± 5% of the increase in arterial plasma noradrenaline concentration was extracted in the forearm. 5. The venous plasma noradrenaline threshold concentration was found to be much lower than previously reported. It is concluded that arterial and venous plasma noradrenaline concentrations which are readily encountered in physiological circumstances elicit haemodynamic effects.

Hemodynamic and sympathoadrenal responses to mental stress during nitric oxide synthesis inhibition

2004 ◽  
Vol 287 (5) ◽  
pp. H2309-H2315 ◽  
Author(s):  
Madeleine Lindqvist ◽  
Anders Melcher ◽  
Paul Hjemdahl
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Heart Rate ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Vascular Resistance ◽  
Mental Stress ◽  
Stress Test ◽  
Arterial Plasma ◽  
Forearm Vascular Resistance

Cardiovascular and sympathoadrenal responses to a reproducible mental stress test were investigated in eight healthy young men before and during intravenous infusion of the nitric oxide (NO) synthesis inhibitor N-monomethyl-l-arginine (l-NMMA). Before l-NMMA, stress responses included significant increases in heart rate, mean arterial pressure, and cardiac output (CO) and decreases in systemic and forearm vascular resistance. Arterial plasma norepinephrine (NE) increased. At rest after 30 min of infusion of l-NMMA (0.3 mg·kg−1·min−1 iv), mean arterial pressure increased from 98 ± 4 to 108 ± 3 mmHg ( P < 0.001) because of an increase in systemic vascular resistance from 12.9 ± 0.5 to 18.5 ± 0.9 units ( P < 0.001). CO decreased from 7.7 ± 0.4 to 5.9 ± 0.3 l/min ( P < 0.01). Arterial plasma NE decreased from 2.08 ± 0.16 to 1.47 ± 0.14 nmol/l. Repeated mental stress during continued infusion of l-NMMA (0.15 mg·kg−1·min−1) induced qualitatively similar cardiovascular responses, but there was a marked attenuation of the increase in mean arterial blood pressure, resulting in similar “steady-state” blood pressures during mental stress without and with NO blockade. Increases in heart rate and CO were attenuated, but stress-induced decreases in systemic and forearm vascular resistance were essentially unchanged. Arterial plasma NE increased less than during the first stress test. Thus the increased arterial tone at rest during l-NMMA infusion is compensated for by attenuated increases in blood pressure during mental stress, mainly through a markedly attenuated CO response and suppressed sympathetic nerve activity.

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