Article

Skin temperature during sympathetic block: a clinical comparison of bupivacaine 0.5% and ropivacaine 0.5% or 0.75%.

Department of Medical and Surgical Critical Care, Unit of Anaesthesia and Intensive Care, University of Florence, Italy.
Anaesthesia and intensive care (Impact Factor: 1.47). 07/2006; 34(3):334-7.
Source: PubMed

ABSTRACT Measurement of skin temperature can be used as an indicator of sympathetic blockade induced by neuraxial anaesthesia. The aim of the study was to test the skin temperature response to epidural administration of bupivacaine and different concentrations of ropivacaine. Forty-eight ASA class I-II patients undergoing herniorraphy were enrolled into a prospective, randomized, double-blind clinical trial. Patients were randomly allocated to receive epidural anaesthesia with a single dose of 18 ml of bupivacaine 0.5% (n=16); ropivacaine 0.5% (n=16), or ropivacaine 0.75% (n=16). A temperature probe was positioned on the skin of the thigh and skin temperature registered before epidural anaesthesia, every 10 minutes for the first hour after the epidural injection and every hour for the following four hours. Sensory blockade was assessed by pinprick and motor blockade using the Bromage scale. No significant difference was observed in sensory or motor blockade. A skin temperature rise of 1 to 1.8 degrees C compared with basal values was observed in all patients within the first hour. Temperature returned to basal values within four hours in the ropivacaine 0.5% group, within five hours in the ropivacaine 0.75% group, and remained 1 degrees C higher after five hours in the bupivacaine 0.5% group (P<0.01). The duration of sympathetic block is significantly shorter with ropivacaine than with bupivacaine.

0 Followers
 · 
80 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: CONTEXT: Thoracic epidural anaesthesia (TEA) is increasingly used in high-risk surgical patients. We recently demonstrated that TEA-mediated cardiac sympathicolysis prevents the native right ventricular positive inotropic response to the induction of acute pulmonary hypertension. OBJECTIVES: In this subsequent study, we induced a selective TEA after acute pulmonary hypertension had been established. We hypothesised that TEA in these circumstances would also exert negative inotropic effects on the right ventricle, not being mediated by possible effects on vasotonus, right ventricular coronary flow dynamics or right ventricular oxygen balance. DESIGN: Randomised placebo-controlled animal study. SETTING: University hospital animal laboratory. INTERVENTIONS: Eighteen pigs were instrumented with an epidural catheter at the thoracic or lumbar level, a right ventricular pressure-volume catheter, transonic flow probes around the pulmonary artery and the right coronary artery, a pressure catheter in the pulmonary artery and a 22-G catheter within a right ventricular free wall coronary vein. Right ventricular pressure overload was induced by constricting the pulmonary artery. After haemodynamic stabilisation, animals were then assigned to receive TEA (n = 6, 1 ml bupivacaine 0.5%), lumbar epidural anaesthesia (LEA) (n = 6, 4 ml bupivacaine 0.5%) or control (n = 6, isotonic saline). The extent of the sympathetic block was assessed by thermography. Final measurements were performed 30 min after the induction of epidural anaesthesia. RESULTS: Pulmonary artery constriction increased pulmonary artery effective elastance and right ventricular contractility in all groups. TEA caused a sympathetic block ranging from C6 to T6, whereas LEA caused a block from T13 to L5. TEA decreased right ventricular contractility (1.5 +/- 0.6 vs. 3.2 +/- 0.9 mW s ml(-1)) and cardiac output (1.8 +/- 0.3 vs. 2.4 +/- 0.3 l min(-1)), although systemic vascular resistance was unaffected. In the LEA group, systemic vascular resistance decreased, but right ventricular contractility remained unchanged. Right ventricular coronary flow, oxygen delivery and consumption were comparable between the groups. CONCLUSION: During acute pulmonary hypertension, selective blockade of cardiac sympathetic nerves by TEA acutely abolished the protective adaptation of right ventricular contractility to right ventricular pressure overload and deteriorated systemic haemodynamics. This effect was attributable solely to the depression of right ventricular contractility and was neither the result of impaired right ventricular coronary flow dynamics nor of systemic vasodilation
    European Journal of Anaesthesiology 07/2011; 28(7). DOI:10.1097/EJA.0b013e328346adf3 · 3.01 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Diagnostic injections are used to diagnose myriad pain conditions, but are characterized by a high false-positive rate. One potential cause of inaccurate diagnostic blocks is the use of sedation. We sought to determine the effect of sedation on the validity of diagnostic injections. Randomized, crossover study in which 73 patients were allocated to receive a diagnostic sacroiliac joint or sympathetic nerve block performed either with or without sedation using midazolam and fentanyl. Those who obtained equivocal relief, good relief lasting less than 3 months, or who were otherwise deemed good candidates for a repeat injection, received a subsequent crossover injection within 3 months (N = 46). A tertiary care teaching hospital and a military treatment facility. In the primary crossover analysis, blocks performed with sedation resulted in a larger mean reduction in pain diary score than those done without sedation (1.2 [2.6]; P = 0.006), less procedure-related pain (difference in means 2.3 [2.5]; P < 0.0001), and a higher proportion of patients who obtained > 50% pain relief on their pain diaries (70% vs. 54%; P = 0.039). The increased pain reduction was not accompanied by increased satisfaction (sedation mean 3.9 [1.1] vs. 3.7 [1.3]; P = 0.26). Similar findings were observed for the parallel group (N = 73) and omnibus (all sedation vs. no sedation blocks, N = 110) analyses. No differences in outcomes were noted between the use and non-use of sedation at 1-month. The use of sedation during diagnostic injections may increase the rate of false-positive blocks and lead to misdiagnoses and unnecessary procedures, but has no effect on satisfaction or outcomes at 1-month.
    Pain Medicine 02/2014; 15(4). DOI:10.1111/pme.12389 · 2.24 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cancer surgery still represents the main treatment indication for a large variety of cancers. At the time of surgery, an unknown number of dormant tumors may already exist distal to the primary cancer. At the same time, a large number of malignant circulating cells are released into the blood stream due to tumor manipulation. The immune system plays an important role in clearing cancer cells, thus a competent immune system is required to avoid further progression of the minimal residual disease in the perioperative period. Unfortunately, volatile anesthetics, opioids and surgical stress cause significant immune depression. At the humoral level, there is a predominant increase in pro-tumor cytokines such as interleukin 4 and 10. At the cellular level, there is impairment in the function of natural killer cells. An alternative, to a volatile-opioid general anesthetic technique is the use of regional anesthesia and analgesia, since this reduces the consumption of volatile anesthetics, opioids and diminishes surgical stress. Thus, it has been speculated that regional anesthesia may improve cancer recurrence when used during “curative” surgery. Although, animal experiments suggest that the use of regional anesthesia may reduce further tumor growth; to date, there is no solid clinical evidence to suggest that the use of regional anesthesia or analgesia may reduce cancer recurrence. Unfortunately, all evidence comes from retrospective studies.
    European Journal of Pain Supplements 11/2011; 5(2):345-355. DOI:10.1016/j.eujps.2011.08.017

Full-text

Download
11 Downloads
Available from
Oct 12, 2014