Heart rate changes as an autonomic component of the pain response

Abstract

Autonomic variables have been recommended as measures of the affective-motivational component of the pain response in objective algesimetry. In the present study components of heart rate responses to painful heat stimuli and their relation to stimulus and sensation variables were analyzed. Twelve healthy subjects served. Sixty phasic stimuli of varying temperatures above and below pain threshold were delivered through a Marstock thermode in 1 session. Heart rate, respiration, and subjective stimulus ratings were recorded simultaneously. Phasic heat stimulation above and below pain threshold induced a tonic increase of the heart rate lasting up to more than 20 sec. High intensity stimulation generated steeper rises and greater mean increase than low intensity stimulation. In general, heart rate responses were more closely related to subjective sensation than to stimulus intensity. However, differential temporal analysis demonstrates that, until about 3 sec after stimulation, the autonomic response is determined solely by stimulus temperature, whereas, after approximately 6 sec, it is related only to subjective judgement. Accordingly, the heart rate responses reflect both a brief nocifensive reflex induced by the sensory component and, subsequently, a longer-lasting response which seems to be related to affective and/or cognitive evaluation. This separation of different stages of pain-processing by an autonomic indicator may be useful in clinical algesimetry.

Vital Signs Are Not Associated with Self-Reported Acute Pain Intensity in the Emergency Department

“…22,27,30,31 Furthermore, the retrospective study design could not control for vital signs prior to the pain stimuli and for other factors that could influence changes in vital signs.…”

“…[22][23][24][25][26][27][28][29][30] Pain intensity is subjective, and with conflicting results, researchers have tried to identify unbiased parameters (including vital signs) to validate pain intensity. HR (or HR variability), more than blood pressure, has been associated with pain intensity, [22][23][24]27,[31][32][33][34] but mostly in males. 29,30 Some studies do not support this association.…”

“…28,33,35,39 Most studies have failed to show an association between pain and respiratory rate. 22,24,26,28,31,33,37,39 Transcutaneous oxygen, skin conductance, and the analgesia/nociception index (calculated from HR variability) have been assessed in patients experiencing pain with inconsistent conclusions. 23,27,31,32,34,38,[40][41][42] Patients with severe pain who show no hypertension or tachycardia to substantiate their pain intensity might not receive the aggressive pain treatment they warrant.…”

Influence of Cancer Severity and Functional Status of Cancer on Cardiac Parasympathetic Indicators

“…In this study, we observed FPS score increased while vagal function reduced. Pain normally accompanies disease and the intensity of pain coincides with the disease progression and rise in sympathetic activity and a decrease in vagal activity is typically associated with pain [32,33]. Thus, negative correlation observed between r-MSSD with FPS score suggests that in cancer patient, decrease in vagal function is linked to the intensity of pain endured by the patients due to increased tumor burden.…”

Controle da dor por bloqueio peridural e incidência de disritmias cardíacas no pós-operatório de procedimentos cirúrgicos torácicos e abdominais altos: estudo comparativo

“…The continuous observation of ECG for 24 hours showed that 55% of patients of Group B and 10% of Group A had ventricular dysrhythmias. Dysrhythmias are common complications in immediate postoperative period 17,18 , even more common after thorax surgeries. A study registered dysrhythmias in the postoperative period of 20% of 185 patients undergoing thoracotomies 19 .…”