There are over 1200 articles of published literature on the three VS Diagnostics tests.
Below please find a selection of representative articles with regards to Pain Management Studies:
As excerpted from: Autonomic function and arterial elasticity testing: A brief summary of the evidence for the use of heart rate variability, sudomotor function and pulse wave velocity tests in clinical practice.
Briefly: As Koenig outlined in his 2013 review paper on the topic, “The systems controlling cardiovascular function are closely coupled to systems modulating the perception of pain (Randich and Maixner, 1984) and extensive interactions between the neural structures involved in pain sensation and autonomic control can be observed (Benarroch, 2001; Benarroch, 2006).” Koenig further stated in his 2016 review that, “The functional interaction of these systems is an important component involved in the endogenous modulation of pain, and there is strong evidence that the functionality of these networks is altered in patients with chronic pain” (Koenig J et al, 2016). Indeed, a recent study using simultaneous HRV and fMRI showed that bodily pain does in fact induce pain- processing brainstem nuclei to function in concert with autonomic nuclei in the production of the observed cardio-vagal pain response (Sclocco R, 2016).
Does heart rate variability predict hypotension and bradycardia after induction of general anaesthesia in high risk cardiovascular patients?
R. Hanss, J. Renner, C. Ilies, L. Moikow, O. Buell, M. Steinfath, J. Scholz and B. Bein
Briefly: This study investigated whether heart rate variability predicts haemodynamic events in high risk patients, defined as Revised Cardiac Risk Index score = 3, scheduled for general anaesthesia. Fifty patients underwent baseline measurement of heart rate variability and were then assigned according to haemodynamic events (hypotension or bradycardia) after standardised induction of anaesthesia into ‘stable’ (n = 39) and ‘unstable’ patients (n = 11). Unstable patients had significantly lower baseline total power. Total power < 500 ms2.Hz) was associated with high sensitivity and specificity for the prediction of hypotension or bradycardia. Prospectively, 29 patients with total power < 500 ms2.Hz) were compared with 21 patients with total power >500 ms2.Hz). Differences were found in the lowest mean arterial pressure and heart rate after induction of anaesthesia. We conclude that the pre-operative total power of heart rate variability in high risk patients may indicate the occurrence of haemodynamic events with high sensitivity and specificity. Heart rate variability may be a suitable tool to identify patients at high risk of a haemodynamic event and may be used to indicate need for intensive monitoring and, perhaps, prophylactic treatment.
Risk Factors for Cardiovascular Complications Following Total Joint Replacement Surgery
Frederick C. Basilico, MD, Gerard Sweeney, MD, Elena Losina, PhD, James Gaydos, MS, PT, Debra Skoniecki, MS, ANP, Elizabeth A. Wright, PhD, and Jeffrey N. Katz, MD, MSc
Briefly: This case–control study identified 2 new risk factors for cardiac complications following TJR: bilateral and revision surgery. The study also confirmed previously documented risk factors, including older age at surgery and a history of arrhythmia and of other cardiac problems. These findings should help clinicians anticipate and prevent cardiac complications following TJR surgery.
Chronic pain, pain and heart rate variability in cross-sectional occupational sample
Julian Koenig, Adrian Loerbroks, Marc N. Jarczok, Joachim E. Fischer, Julian F. Thayer
Briefly: The vagus nerve influences the modulation of pain. Chronic pain is associated with disturbance of the descendent inhibitory pathway (DIP). Heart rate variability (HRV) is a proxy measure for vagal activity and may reflect dysfunction of the DIP. We aimed to investigate the association of HRV and pain in individuals with and without chronic pain.
Our results suggest that the DIP indexed by vagal activity operationalized as RMSSD is disturbed in persons with chronic pain. Furthermore, the correlations between RMSSD and pain are different between those without and those with chronic pain. The findings are discussed, emphasizing changes in brain activity and the comorbid dysregulation of emotion in patients with chronic pain, to provide implications for the treatment of chronic pain.
Interactions between the cardiovascular and pain regulatory systems: an updated review of mechanisms and possible alterations in chronic pain
Briefly: Endogenous pain regulatory system dysfunction appears to play a role in the maintenance of chronic pain. An important component of the pain regulatory process is the functional interaction between the cardiovascular and pain regulatory systems, which results in an association between elevated resting blood pressure (BP) and diminished acute pain sensitivity. This BP/pain sensitivity relationship is proposed to reflect a homeostatic feedback loop helping restore arousal levels in the presence of painful stimuli. Evidence is emerging that this normally adaptive BP/pain sensitivity relationship is significantly altered in chronic pain conditions, affecting responsiveness to both acute and chronic pain stimuli. Several mechanisms that may underlie this adaptive relationship in healthy individuals are overviewed, including endogenous opioid, noradrenergic, and baroreceptor-related mechanisms. Theoretical models are presented regarding how chronic pain-related alterations in the mechanisms above and increased pain facilatory system activity (central sensitization) may contribute to altered BP/pain sensitivity interactions in chronic pain. Clinical implications are discussed.
Heart rate variability: a diagnostic and prognostic tool in anesthesia and intensive care.
Mazzeo AT, La Monaca E, Di Leo R, Vita G, Santamaria LB.
Briefly: The autonomic nervous system (ANS) plays an important role in the human response to various internal and external stimuli, which can modify homeostasis, and exerts a tight control on essential functions such as circulation, respiration, thermoregulation and hormonal secretion. ANS dysfunction may complicate the perioperative course in the surgical patient undergoing anesthesia, increasing morbidity and mortality, and, therefore, it should be considered as an additional risk factor during pre-operative evaluation.
Increase in heart attack risk after joint surgery low but persistent
Briefly: There’s an old saying in the news business: If it bleeds it leads. So when a recent study in the Archives of Internal Medicine announced that the risk of having a heart attack is up to 31 times higher immediately following joint replacement surgery, it was a headline opportunity health reporters found hard to resist.
Those relative risk numbers (they compare heart attack rates between people who had joint-replacement surgery and those who didn’t) could be terrifying for someone who needs to have a knee or hip replaced. The absolute risk numbers offer some reassurance. In the six weeks following surgery, one in 200 people in the study who got a new hip and one in 500 who had a knee replaced suffered a heart attack.