scholarly journals Instantaneous Response Patterns of Baroreflex Sensitivity, Respiratory Sinus Arrhythmia Sensitivity and Vagal Activity to Cold Face Test and Active Orthostatic Test

2016 ◽  
Author(s):  
Salvador Carrasco-Sosa ◽  
Alejandra Guillen-Mandujano ◽  
Aldo R. Mejia-Rodriguez
Keyword(s):  
Respiratory Sinus Arrhythmia ◽  
Baroreflex Sensitivity ◽  
Vagal Activity ◽  
Response Patterns ◽  
Orthostatic Test ◽  
Sinus Arrhythmia ◽  
Cold Face ◽  
Cold Face Test

The cold face test (diving reflex) in clinical autonomic assessment: methodological considerations and repeatability of responses

1990 ◽  
Vol 78 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Martha E. Heath ◽  
John A. Downey
Keyword(s):  
Blood Flow ◽  
Venous Occlusion ◽  
Valsalva Manoeuvre ◽  
Sinus Arrhythmia ◽  
Diving Reflex ◽  
Cold Stimulus ◽  
Peripheral Vasoconstriction ◽  
Clinical Autonomic ◽  
Cold Face ◽  
Cold Face Test

1. Cold stimulus applied to the face causes bradycardia and peripheral vasoconstriction (i.e. the diving reflex), and has been suggested as a test of the autonomic pathways involved. The purpose of this study was to define standard procedures for conducting the test and analysing the responses to the cold face test, to evaluate variability in responses between subjects and within subjects when the same test is repeated, and to examine its usefulness in clinical autonomic assessment. 2. Sixteen (nine female, seven male) healthy adult (21–35 years old) subjects were used. Cold stimulus was applied with gel-filled compresses. Forehead temperature under the compress as an indication of stimulus magnitude, heap rate, blood flow in the finger, toe and calf by venous occlusion plethysmography, and systolic and diastolic blood pressure were monitored. Three protocols were carried out in which the temperature (0, 5, 10, 15°C), placement (whole face, unilateral, forehead) and duration (20, 40, 60, 120 s) of the cold compress application were varied. 3. The data indicate that 0°C compresses applied bilaterally for 40 s produced the maximum bradycardia and peripheral vasoconstriction. No subject found this test to be obnoxious, but a 120 s application was objectionable to some subjects. This cold face test resulted in 22%, 72%, 59% and 44% reductions in heart rate and blood flow to the finger, toe and calf, respectively. There was significant between-subject variability, but good consistency in responses to tests repeated in the same subject on different days, at different times of day and in different seasons. 4. Two advantages of the cold face test are: (a) it can assess sympathetic-vascular smooth muscle pathways as well as the cardiac-vagal pathway; and (b) because its afferents are independent of the stretch and pressure receptors that are stimulated in other vagal–cardiac tests (Valsalva manoeuvre and respiratory sinus arrhythmia), it can help differentiate between abnormal vagal–cardiac and abnormal transducer–afferent pathway function.

scholarly journals Does respiratory sinus arrhythmia occur in fishes?

2005 ◽  
Vol 1 (4) ◽  
pp. 484-487 ◽  
Author(s):  
Hamish A Campbell ◽  
Edwin W Taylor ◽  
Stuart Egginton
Keyword(s):  
Heart Rate ◽  
Respiratory Sinus Arrhythmia ◽  
Selection Pressure ◽  
Vagal Activity ◽  
Sinus Arrhythmia ◽  
Antarctic Species ◽  
Power Spectral ◽  
Spectral Statistics ◽  
Respiratory Modulation ◽  
Environmental Temperatures

The hypothesis that respiratory modulation of heart rate variability (HRV) or respiratory sinus arrhythmia (RSA) is restricted to mammals was tested on four Antarctic and four sub-Antarctic species of fish, that shared close genotypic or ecotypic similarities but, due to their different environmental temperatures, faced vastly different selection pressures related to oxygen supply. The intrinsic heart rate ( f H ) for all the fish species studied was ∼25% greater than respiration rate ( f V ), but vagal activity successively delayed heart beats, producing a resting f H that was synchronized with f V in a progressive manner. Power spectral statistics showed that these episodes of relative bradycardia occurred in a cyclical manner every 2–4 heart beats in temperate species but at >4 heart beats in Antarctic species, indicating a more relaxed selection pressure for cardio-respiratory coupling. This evidence that vagally mediated control of f H operates around the ventilatory cycle in fish demonstrates that influences similar to those controlling RSA in mammals operate in non-mammalian vertebrates.

Effects of hypercapnia and hypoxemia on respiratory sinus arrhythmia in conscious humans during spontaneous respiration

2007 ◽  
Vol 292 (5) ◽  
pp. H2397-H2407 ◽  
Author(s):  
Y. C. Tzeng ◽  
P. D. Larsen ◽  
D. C. Galletly
Keyword(s):  
Tidal Volume ◽  
Respiratory Sinus Arrhythmia ◽  
Amplitude Ratio ◽  
Low Frequency ◽  
Vagal Tone ◽  
Mean Amplitude ◽  
Spontaneous Respiration ◽  
Vagal Activity ◽  
Sinus Arrhythmia ◽  
Amplitude Increase

Normally, at rest, the amplitude of respiratory sinus arrhythmia (RSA) appears to correlate with cardiac vagal tone. However, recent studies showed that, under stress, RSA dissociates from vagal tone, indicating that separate mechanisms might regulate phasic and tonic vagal activity. This dissociation has been linked to the hypothesis that RSA improves pulmonary gas exchange through preferential distribution of heartbeats in inspiration. We examined the effects of hypercapnia and mild hypoxemia on RSA-vagal dissociation in relation to heartbeat distribution throughout the respiratory cycle in 12 volunteers. We found that hypercapnia, but not hypoxemia, was associated with significant increases in heart rate (HR), tidal volume, and RSA amplitude. The RSA amplitude increase remained statistically significant after adjustment for respiratory rate, tidal volume, and HR. Moreover, the RSA amplitude increase was associated with a paradoxical rise in HR and decrease in low-frequency-to-high-frequency mean amplitude ratio derived from spectral analysis, which is consistent with RSA-vagal dissociation. Although hypercapnia was associated with a significant increase in the percentage of heartbeats during inspiration, this association was largely secondary to increases in the inspiratory period-to-respiratory period ratio, rather than RSA amplitude. Additional model analyses of RSA were consistent with the experimental data. Heartbeat distribution did not change during hypoxemia. These results support the concept of RSA-vagal dissociation during hypercapnia; however, the putative role of RSA in optimizing pulmonary perfusion matching requires further experimental validation.

Respiratory Sinus Arrhythmia in Blood Phobic Subjects

1997 ◽  
Vol 84 (2) ◽  
pp. 505-506 ◽  
Author(s):  
Alessandro Angrilli ◽  
Michela Sarlo ◽  
Daniela Palomba ◽  
Micaela Schincaglia ◽  
Luciano Stegagno
Keyword(s):  
Heart Rate ◽  
Respiratory Sinus Arrhythmia ◽  
Vagal Activity ◽  
Sinus Arrhythmia ◽  
Control Subjects ◽  
Paced Respiration ◽  
Autonomic Index ◽  
Vagal Influence

12 blood-phobic subjects, selected according to the Feat Survey Schedule and the Mutilation Questionnaire, and 50 control subjects performed a paced respiration task during which heart rate and respiration were recorded. Respiratory Sinus Arrhythmia (RSA) was analyzed as an autonomic index of vagal influence on the heart. Analysis showed a larger RSA in the blood-phobic group than the controls and points to a difference in vagal activity at rest between the groups.

Reduced baroreflex sensitivity in elderly humans is not due to efferent autonomic dysfunction

1999 ◽  
Vol 98 (1) ◽  
pp. 103-110 ◽  
Author(s):  
D. O'MAHONY ◽  
C. BENNETT ◽  
A. GREEN ◽  
A. J. SINCLAIR
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Baroreflex Sensitivity ◽  
Reflex Response ◽  
Cognitive Stress ◽  
Age Related ◽  
Cold Face ◽  
Blood Pressure Responses ◽  
Age Range ◽  
Cold Face Test

A progressive decline in baroreflex sensitivity (BRS) is a characteristic feature of human aging, the basis of which is poorly understood. The purpose of the present study was to determine whether alterations in efferent baroreflex function might contribute to the age-related decrease in BRS. We studied 10 healthy young (mean age 30.5 years; age range 22–40 years; six male) and 10 healthy elderly (mean age 70.7 years; age range 67–75 years; five male) volunteers. We tested efferent cardiac vagal function using the bradycardiac response to the cold face test, and efferent sympathetic function using heart rate and blood pressure responses to four stress tests: (i) low-level cognitive stress, (ii) high-level cognitive stress, (iii) hand immersion in ice water (cold pressor test) and (iv) isometric sustained hand-grip. Haemodynamic responses to these stresses are mediated via efferent baroreflex pathways, whereas the afferent components of each reflex response are independent of afferent baroreflex pathways. BRS was measured from simultaneous Finapres-derived continuous blood pressure and digital ECG R–R interval data using the sequence analysis paradigm. As expected, BRS was significantly reduced in the elderly group (7.29±0.74 ms/mmHg; mean±S.E.M.) compared with the young group (13.84±1.13 ms/mmHg; P < 0.001). However, neither the bradycardiac responses to the cold face test nor the efferent sympathetically mediated heart rate/blood pressure responses to the stress test battery were significantly different between the young and elderly groups. We conclude that the age-related decrease in BRS is not attributable to impairments in the efferent sympathetic or parasympathetic system components of the baroreceptor reflex pathway.

Carotid baroreflex responsiveness in high-fit and sedentary young men

1988 ◽  
Vol 65 (5) ◽  
pp. 2190-2194 ◽  
Author(s):  
J. A. Barney ◽  
T. J. Ebert ◽  
L. Groban ◽  
P. A. Farrell ◽  
C. V. Hughes ◽  
...  
Keyword(s):  
Baroreflex Sensitivity ◽  
Cardiac Activity ◽  
Young Men ◽  
The Other ◽  
Vagal Activity ◽  
O2 Consumption ◽  
Sinus Arrhythmia ◽  
Carotid Baroreflex ◽  
History Of ◽  
Sedentary Subjects

The influence of fitness on cardiac vagal activity and baroreflex-mediated control of heart rate has not been clearly established in humans. Therefore, we studied resting cardiac vagal activity by evaluating respiratory sinus arrhythmia (RSA) and examined carotid-cardiac baroreflex responsiveness with a neck collar in 11 high-fit and 9 sedentary [based on maximal O2 consumption (VO2max) and history of physical activity] healthy young men (19-31 yr of age). Resting cardiac vagal activity was determined from the standard deviation of 100 consecutive resting R-R intervals. Baroreflex responsiveness was determined from the R-R interval responses to neck suction and pressure (repeated trials of 5-s stimuli of -20, -40, and 35 mmHg). Both RSA and the bradycardic (R-R interval) responses to neck suction of -40 mmHg were significantly greater (P less than 0.05) in the high-fit individuals (RSA, 116.5 +/- 11.5 ms; neck-suction response, 145.3 +/- 17.0 ms; mean +/- SE) compared with sedentary subjects (RSA, 65.2 +/- 6.6 ms; neck-suction response, 86.9 +/- 12.5 ms). Responses of the high-fit volunteers to the other intensities of neck stimuli (-20 and 35 mmHg) showed a similar trend but were not significantly different from those of the sedentary volunteers. The baroreflex slope derived from these data was significantly greater in the high-fit subjects (4.00 +/- 0.39 ms/mmHg) compared with the sedentary controls (2.53 +/- 0.28 ms/mmHg). These data suggest that resting cardiac vagal activity is greater, carotid-to-cardiac activity is well maintained, and baroreflex sensitivity, i.e., slope, is augmented in high-fit subjects.

Sign in / Sign up

Export Citation Format

Share Document