Patients with complex regional pain syndrome type 1: fractal dynamics of heart rate variability and baroreflex evaluations.

Objective: Patients with complex regional pain syndrome type 1 might have disturbed autonomic function and increased heart rate fractal dynamics with a resultant impaired baroreflex sensitivity (BRS). We hypothesized that these parameters of impaired cardiovascular regulation might improve with a reduction of pain intensity.

Methods: Ten patients and 10 healthy volunteers entered the study.

Fractal cardiovascular dynamics and baroreflex sensitivity after stellate ganglion block.

Background: It has been shown that stellate ganglion block can attenuate baroreflex sensitivity. Our primary purpose in this study was to determine whether fractal dynamics (dynamic change of self-similar fluctuation patterns) of not only heart rate but also systolic blood pressure variability are involved in attenuation of baroreflex sensitivity after stellate ganglion block.

Methods: Sixteen young, healthy volunteers entered the study.

In rabbits, landiolol, a new ultra-short-acting beta-blocker, exerts a more potent negative chronotropic effect and less effect on blood pressure than esmolol.

Purpose: To compare the cardiovascular and sympathetic effects of a new ultra-short-acting, highly cardioselective beta- blocker, landiolol, with esmolol, using an in vivo rabbit model.

Methods: Different bolus doses of landiolol (0.3, 1.

Surgical stress attenuates reflex heart rate response to hypotension.

Purpose: The baroreflex-mediated increase in heart rate (HR) in response to acute reduction of systolic blood pressure (SBP) was studied in order to assess whether the changes in arterial baroreflex sensitivity depend on the intensity of surgical stress, and location of visceral and somatic stimulation during surgery.

Methods: Patients were divided into visceral stimulation groups [upper (n = 30) and lower (n = 30) abdominal surgery] and somatic stimulation groups [upper (n = 25) and lower (n = 25) limbs, and chest wall (n = 25) surgery]. Acute hypotension as a baroreflex depressor test was induced by prostaglandin E1 (PGE1) 10 min before surgical incision (control) and during surgical manipulation under isoflurane-N2O anaesthesia or isoflurane-N2O-fentanyl anaesthesia.

Adenosine triphosphate attenuates renal sympathetic nerve activity through left ventricular chemosensitive receptors.

We previously reported that ATP, but not adenosine, administered i.v. attenuates the baroreflex-mediated increase in sympathetic nerve activity in response to arterial hypotension by a vagal afferent mechanism.