Biventricular function in exercise during autonomic (thoracic epidural) block.

Background: Blockade of cardiac sympathetic fibers by thoracic epidural anesthesia (TEA) was previously shown to reduce right and left ventricular systolic function and effective pulmonary arterial elastance. At conditions of constant paced heart rate, cardiac output and systemic hemodynamics were unchanged. In this study, we further investigated the effect of cardiac sympathicolysis during physical stress and increased oxygen demand.

Effects of Thoracic Epidural Anesthesia on Neuronal Cardiac Regulation and Cardiac Function.

Cardiac sympathetic blockade with high-thoracic epidural anesthesia is considered beneficial in patients undergoing major surgery because it offers protection in ischemic heart disease. Major outcome studies have failed to confirm such a benefit, however. In fact, there is growing concern about potential harm associated with the use of thoracic epidural anesthesia in high-risk patients, although underlying mechanisms have not been identified.

Effect of increasing age on the haemodynamic response to thoracic epidural anaesthesia: an observational study.

Background: Sympathetic blockade with thoracic epidural anaesthesia (TEA) results in circulatory changes and may directly alter cardiac function. Ageing is associated with an impairment of autonomic nervous system control and a deterioration of myocardial diastolic performance.

Objectives: We postulated that haemodynamic changes induced by TEA could vary with age.

Cardiovascular parameters and liver blood flow after infusion of a colloid solution and epidural administration of ropivacaine 0.75%: the influence of age and level of analgesia.

Background And Objective: Lumbar epidural anaesthesia induces cardiovascular changes and decreases liver blood flow (Qh). We studied the effects of age on haemodynamics, blood volumes and Qh before and after epidural anaesthesia.

Methods: Thirty-six patients were enrolled as follows: group 1, 20-44 years; group 2, 45-70 years; group 3, >70 years.

Population pharmacokinetic-pharmacodynamic modeling of epidural anesthesia.

Background: In previous studies, the authors reported on the absorption and disposition kinetics of levobupivacaine and ropivacaine. The current study was designed to develop a population pharmacokinetic-pharmacodynamic model capable of linking the kinetic data to the analgesic effects of these local anesthetics (i.e.

Are epidurals worthwhile in vascular surgery?

Purpose Of Review: Patients undergoing major vascular surgery are at increased risk for postoperative complications due to the high incidence of comorbidities in this population.Epidural anaesthesia provides potential benefits but its effect on morbidity and mortality is unclear.

Recent Findings: Existing studies fail to demonstrate improved clinical outcome and reduced mortality for epidural anaesthesia or combined epidural/general techniques compared with general anaesthesia.

The effect of a long term epidural infusion of ropivacaine on CYP2D6 activity.

Background: Ropivacaine and one of its metabolites, pipecoloxylidide, inhibit CYP2D6 in. human liver microsomes in vitro with K(i) values of 5 microM (1.4 mg/L) and 13 microM (3.

Complications and local anaesthetic toxicity in regional anaesthesia.

Purpose Of Review: Local anaesthetic agents are administered every day in clinical practice. These agents are relatively safe when administered in proper dosages at appropiate anatomical sites. However, when excessive dosages are administered or the incorrect site of administration is used there is a potential for toxic reactions.

The effect of age on the systemic absorption and systemic disposition of ropivacaine after epidural administration.

Knowledge about the systemic absorption and disposition of ropivacaine after epidural administration is important in regard to its clinical profile and the risk of systemic toxicity. We investigated the influence of age on the pharmacokinetics of ropivacaine 1.0% after epidural administration, using a stable-isotope method.

Maximum recommended doses of local anesthetics: a multifactorial concept.

The current recommendations regarding maximum doses of local anesthetics presented in textbooks, or by the responsible pharmaceutical companies, are not evidence based (ie, determined by randomized and controlled studies). Rather, decisions on recommending certain maximum local anesthetic doses have been made in part by extrapolations from animal experiments, clinical experiences from the use of various doses and measurement of blood concentrations, case reports of local anesthetic toxicity, and pharmacokinetic results. The common occurrence of central nervous system toxicity symptoms when large lidocaine doses were used in infiltration anesthesia led to the recommendation of just 200 mg as the maximum dose, which has remained unchanged for more than 50 years.

The epidural "top-up": predictors of increase of sensory blockade.

Background: Extension of sensory blockade after an epidural top-up in combined spinal epidural (CSE) anesthesia is partly attributed to compression of the dural sac by the injected volume. This study investigated whether a volume effect plays a significant role when administering an epidural top-up after an initial epidural loading dose and assessed the predictive value of different factors with respect to the increase in sensory blockade.

Methods: After an epidural loading dose of 75 mg ropivacaine, 0.

Pharmacokinetics of bupivacaine during postoperative epidural infusion: enantioselectivity and role of protein binding.

Background: Changing plasma protein concentrations may affect the protein binding and pharmacokinetics of drugs in the postoperative period. This study examined the effect of postoperative increases (in response to surgery) in plasma alpha1-acid-glycoprotein (AAG) concentrations on the plasma concentrations of the enantiomers of bupivacaine during continuous epidural infusion of racemic bupivacaine for postoperative pain relief.

Methods: Six patients scheduled for total hip surgery with combined epidural and general anesthesia received a bolus dose of bupivacaine (65 mg) followed by constant-rate (8 ml/h) epidural infusion of 2.

The effects of age on neural blockade and hemodynamic changes after epidural anesthesia with ropivacaine.

Unlabelled: We studied the influence of age on the neural blockade and hemodynamic changes after the epidural administration of ropivacaine 1.0% in patients undergoing orthopedic, urological, gynecological, or lower abdominal surgery. Fifty-four patients were enrolled in one of three age groups (Group 1: 18-40 yr; Group 2: 41-60 yr; Group 3: > or=61 yr).