Anesthesia and analgesia
-
Anesthesia and analgesia · Sep 2001
Randomized Controlled Trial Clinical TrialInterscalene brachial plexus block with continuous intraarticular infusion of ropivacaine.
Providing intraarticular analgesia with a continuous infusion of local anesthetic via a disposable infusion pump has gained popularity. Despite the prevalence of this technique, data comparing this method of analgesia to conventional regional anesthesia are not available. We present a prospective study that compared a single-dose interscalene block with a single-dose interscalene block plus continuous intraarticular infusion of local anesthetic. ⋯ Visual analog scale scores at rest and with ambulation in the Mepivacaine/Intraarticular Ropivacaine group were reduced when compared with the Ropivacaine/Saline group (rest: P = 0.003, ambulation: P = 0.006). Oxycodone consumption was also decreased (28 +/- 21 mg vs 44 +/- 28 mg, P = 0.046), respectively. We conclude that a brachial plexus block with 1.5% mepivacaine and a continuous intraarticular infusion of 0.5% ropivacaine at 2 mL/h provides improved analgesia for minor surgery at 24 and 48 h versus a single-injection interscalene block with 0.5% ropivacaine.
-
Anesthesia and analgesia · Sep 2001
Randomized Controlled Trial Clinical TrialThe enhancement of sensory blockade by clonidine selectively added to mepivacaine after midhumeral block.
Clonidine added to local anesthetics results in an increased duration of anesthesia or analgesia after brachial plexus block. We investigated the effect of selective application of clonidine to the median and musculocutaneous nerves during midhumeral block, a technique allowing selective nerve blocks with the use of different local anesthetics. Initially, 58 patients scheduled for hand surgery were prospectively enrolled to receive a midhumeral block. ⋯ Adding 50 microg clonidine to the median and musculocutaneous nerves resulted in a significant increase in the duration of sensory block in these nerves (P < 0.0001). Recovery of motor block was not different between the two groups. No significant difference was found between the two groups in the mean plasma mepivacaine concentration.
-
Anesthesia and analgesia · Sep 2001
Randomized Controlled Trial Clinical TrialMetaraminol infusion for maintenance of arterial blood pressure during spinal anesthesia for cesarean delivery: the effect of a crystalloid bolus.
We randomly allocated women having elective cesarean delivery to receive either no bolus (Control Group, n = 31) or 20 mL/kg lactated Ringer's solution (Bolus Group, n = 35) IV before spinal anesthesia. An infusion of metaraminol started at 0.25 mg/min was titrated to maintain systolic arterial blood pressure in the target range 90%-100% of baseline. ⋯ There was no difference between groups in regards to changes in systolic arterial blood pressure or heart rate over time, or maternal or neonatal outcome. We conclude that when metaraminol is used to maintain arterial pressure during spinal anesthesia for cesarean delivery, crystalloid bolus is not essential provided that sufficient vasopressor is given in the immediate postspinal period.
-
Anesthesia and analgesia · Sep 2001
Randomized Controlled Trial Clinical TrialNeither nalbuphine nor atropine possess special antishivering activity.
The special antishivering action of meperidine may be mediated by its kappa or anticholinergic actions. We therefore tested the hypotheses that nalbuphine or atropine decreases the shivering threshold more than the vasoconstriction threshold. Eight volunteers were each evaluated on four separate study days: 1) control (no drug), 2) small-dose nalbuphine (0.2 microg/mL), 3) large-dose nalbuphine (0.4 microg/mL), and 4) atropine (1-mg bolus and 0.5 mg/h). ⋯ This differs markedly from meperidine, which impairs shivering twice as much as vasoconstriction. Atropine increased all thresholds and would thus be expected to facilitate shivering. Our results thus fail to support the theory that activation of kappa-opioid or central anticholinergic receptors contribute to meperidine's special antishivering action.
-
Anesthesia and analgesia · Sep 2001
Clinical TrialDifferential secretion of atrial and brain natriuretic peptide in critically ill patients.
Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are cardiac hormones with natriuretic, vasorelaxant, and aldosterone-inhibiting properties. We analyzed the plasma of 178 critically ill patients for ANP, BNP, aldosterone, and serum sodium concentration, as well as serum and urine osmolality and sodium filtration fraction. Mean plasma concentrations of ANP and BNP were increased in critically ill patients compared with healthy controls (ANP, 14.3 +/- 5.8 pmol/L versus 8.8 +/- 3.2 pmol/L, P < 0.05; BNP, 26.2 +/- 10.7 pmol/L versus 4.6 +/- 2.8 pmol/L, P < 0.0001). ⋯ Our data support a regulatory role for ANP in the maintenance of water and electrolyte balance. The physiologic role of BNP, by contrast, is less clear. ANP and BNP are not predictors for the severity of illness and mortality in critically ill patients.