A5075436418- Anesthesia and Sedative Agents
- Cardiac, Anesthesia and Surgical Outcomes
- Heart Rate Variability and Autonomic Control
- Intensive Care Unit Cognitive Disorders
- Respiratory Support and Mechanisms
- Hemodynamic Monitoring and Therapy
- Neuroscience of respiration and sleep
- Anesthesia and Neurotoxicity Research
- Neuroscience and Neuropharmacology Research
- Cardiac Arrest and Resuscitation
- Cardiovascular Syncope and Autonomic Disorders
- Anesthesia and Pain Management
- Sepsis Diagnosis and Treatment
- Cardiovascular and exercise physiology
- Nitric Oxide and Endothelin Effects
- Airway Management and Intubation Techniques
- Receptor Mechanisms and Signaling
- Complex Systems and Time Series Analysis
- Eicosanoids and Hypertension Pharmacology
- Neurotransmitter Receptor Influence on Behavior
- Cardiac electrophysiology and arrhythmias
- Traumatic Brain Injury and Neurovascular Disturbances
- Blood Pressure and Hypertension Studies
- Thermal Regulation in Medicine
- Chaos control and synchronization
Hôpital d'instruction des Armées Desgenettes
2016-2025
Sorbonne Université
2023
Hôpital Bichat-Claude-Bernard
2023
Groupe de recherche clinique en anesthésie réanimation médecine périopératoire
2023
Georgetown University
2023
Hôpital Pasteur
2019
Institut National des Sciences Appliquées de Lyon
2010-2019
Université Claude Bernard Lyon 1
2008-2017
Alpha MOS (France)
2017
Inserm
1986-2016
This study compared spontaneous baroreflex sensitivity (BRS) estimates obtained from an identical set of data by 11 European centers using different methods and procedures. Noninvasive blood pressure (BP) ECG recordings were in 21 subjects, including 2 subjects with established failure. Twenty-one BRS the two main techniques estimates, i.e., spectral analysis (11 procedures) sequence method (7 but also one trigonometric regressive (TRS), exogenous model autoregressive input (X-AR), Z method....
Abstract We compared two methods of assessment baroreflex sensitivity in eight supine healthy volunteers during repeated baseline measurements and various conditions cardiac autonomic blockade. The spontaneous method involved computer scanning recordings continuous finger arterial pressure electrocardiogram to locate sequences three or more beats which spontaneously increased decreased, with parallel changes pulse intervals. mean regression slope all these each study condition was considered...
The effects of clonidine, a centrally acting alpha 2-adrenergic receptor agonist, on depth fentanyl anesthesia and cardiovascular response to laryngoscopy intubation were studied. Twenty-four patients undergoing aortocoronary bypass surgery (ACBS) with history arterial hypertension, coronary artery disease (NYHA class 3-4), well-preserved left ventricular function assigned randomly either Group 1 (n = 12), who received standard premedication, or 2 clonidine 5 micrograms X kg-1 po in addition...
Heart rate variability is a recognized parameter for assessing autonomous nervous system activity. Fourier transform, the most commonly used method to analyze variability, does not offer an easy assessment of its dynamics because limitations inherent in stationary hypothesis. Conversely, wavelet transform allows analysis nonstationary signals. We compared respective yields and transforms analyzing heart during dynamic changes balance induced by atropine propranolol. were applied sequences...
Summary. Beat‐by‐beat variations in blood pressure and RR‐interval are interrelated by the actions of baroreflex non‐baroreflex responses. This study had two purposes: (1) to examine spontaneous relationships between systolic determine relative occurrence responses humans, (2) compare beat‐sequence method with a cross spectral estimate response slope. Eight healthy men were studied during 10 h quiet, seated rest, six three women rest plus fixed pace breathing, cold pressor test. continuous,...
How the autonomic nervous system influences fractal dynamics of heart rate (HR) and blood pressure (BP) remains unclear. The purpose our study was to separately assess cardiac vagal sympathetic (cardiac vs. vascular) on properties HR BP as described by scale exponents detrended fluctuation analysis (DFA). R-R intervals, systolic diastolic were measured in nine supine volunteers before after administration blocking agents (atropine, propranolol, atropine+propranolol, clonidine). Spectra DFA...
Heart rate self-affinity is often assessed by detrended fluctuations analysis, obtaining two coefficients only: a short-term (alpha(1)) exponent and long-term (alpha(2)) exponent. Our aim to show the limits of this approach alternatively propose estimation whole spectrum local exponents alpha(n) for heart blood pressure. To illustrate advantages approach, we assess effects autonomic activations age on alpha(n). We measured ECG arterial pressure in 60 volunteers 10 min, considering three...
It is unclear whether the complexity of variability systolic arterial pressure (SAP) provides complementary information to that heart period (HP). The HP and SAP variabilities was assessed from short beat-to-beat recordings (i.e., 256 cardiac beats). evaluation made during a pharmacological protocol induced vagal blockade with atropine or sympathetic (beta-adrenergic propranolol central clonidine) alone in combination, graded head-up tilt, patients Parkinson's disease (PD) without...
We studied causal relations among heart period (HP), systolic arterial pressure (SAP) and respiration (R) according to the definition of Granger causality in time domain. Autonomic pharmacological challenges were used alter complexity cardiovascular control. Atropine (AT), propranolol clonidine (CL) administered block muscarinic receptors, β-adrenergic receptors centrally sympathetic outflow, respectively. found that: (i) at baseline, HP SAP interacted a closed loop with dominant direction...
To examine the effect of an alpha-2 agonist, clonidine, on oxygen uptake and incidence postoperative shivering, 28 patients presenting for major abdominal surgery were randomly assigned in a double-blind manner to one two groups. Intraoperatively, 14 received 5 micrograms.kg-1 clonidine infused over 3 h (clonidine group), placebo (placebo group). Oxygen was measured continuously first hours with mass spectrometer system. Circulatory variables, esophageal temperature, skin temperature 6...
Twenty‐eight patients presenting for aortic surgery were randomly assigned in a double‐blind, placebo‐controlled protocol to receive placebo (n=14) or clonidine (4.7 ± 1.2 μg · kg ‐1 po; n=14), addition flunitrazepam 120 min before induction of anesthesia. Plasma catecholamines (CA) and hemodynamic variables determined at 7 stages during surgery. In the group, plasma epinephrine (E) norepinephrine (NE) had risen twofold skin closure compared baseline (E: from 109 51 pg p ml 294 161 ; NE: 658...
During septic shock, vasopressors are a cornerstone of therapy. In very high doses sometimes have to be used due vascular desensitization, the mechanisms which poorly understood. This study assesses whether α-2 agonists increase pressor responsiveness following lipopolysaccharide administration.Parallel groups animals (n = 7 per group) subjected pharmacologic interventions.Physiology laboratory.Rats.In anesthetized rats, responses increasing norepinephrine (norepinephrine-systolic pressure...
Complexity analysis of short-term cardiovascular control is traditionally performed using entropy-based approaches including corrective terms or strategies to cope with the loss reliability conditional distributions pattern length. This study proposes a new approach aiming at estimation entropy (CE) from short data segments (about 250 samples) based on k-nearest-neighbor technique. The main advantages are: (i) length without introducing priori information; (ii) assessment complexity indexes...
In sepsis, prolonged, sympathetic overstimulation may lead to vasopressor-refractory hypotension. We therefore examined the effects of α2-adrenergic agonist clonidine on mean arterial pressure, renal nerve activity, and pressor responsiveness phenylephrine angiotensin II during hypotensive sepsis in conscious sheep.Interventional study.Research institute.Twelve adult Merino ewes (n = 6 per group).Sepsis was induced by IV infusion Escherichia coli for 32 hours. Pressor responses increasing...
The utility of clonidine for hypertensive patients presenting major vascular procedures remains debatable.Twenty-one aortic surgery were given (n = 11) or placebo 10) in a double-blind, randomized manner. Clonidine was administered 6 micro gram/kg per os 120 min before induction anesthesia and 3 intravenously (IV) over 60 from declamping to skin closure. Anesthesia induced with alfentanil 20 gram/kg, midazolam, atracurium maintained nitrous oxide 70%, an infusion (0.25 gram centered dot kg-1...