Canadian journal of anaesthesia = Journal canadien d'anesthésie
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Randomized Controlled Trial Comparative Study Clinical Trial
Left ventricular regional wall motion and haemodynamic changes following bolus administration of pipecuronium or pancuronium to adult patients undergoing coronary artery bypass grafting.
The objective of this study was to compare the haemodynamic and myocardial effects of pipecuronium and pancuronium in patients undergoing coronary artery bypass grafting (CABG) during benzodiazepine/sufentanil anaesthesia. Twenty-seven ASA III-IV patients received lorazepam (1-3 mg) po and midazolam ( < 0.1 mg.kg-1) i.v. before induction of anaesthesia with sufentanil (3-8 micrograms.kg-1) was administered to facilitate tracheal intubation. According to random allocation, each patient received either pipecuronium (150 micrograms.kg-1) or pancuronium (120 micrograms.kg-1) after sternotomy but before heparinization. ⋯ Heart rate, MAP and CO increased after administration of pancuronium (by 13.6 beats.min-1, 10.8 mmHg and 1.0 L.min-1 respectively) but not after pipecuronium (P < 0.05). Evidence of myocardial ischaemia was not detected in any patients using ECG ST segment analysis or TEE assessment of left ventricular wall motion. We conclude that pancuronium caused increases in HR, MAP and CO but that neither pancuronium nor pipecuronium caused myocardial ischaemia.
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Randomized Controlled Trial Comparative Study Clinical Trial
A directional needle improves effectiveness and reduces complications of microcatheter continuous spinal anaesthesia.
The present prospective randomized study compares the impact of two different spinal needle designs--non-directional versus directional--on the effectiveness of continuous spinal anaesthesia provided via a microcatheter in orthopaedic patients. Using the midline approach, a 28-gauge spinal catheter was inserted either through a 22-gauge Quincke needle (non-directional, Group 1, n = 21) or a 22-gauge Sprotte needle (directional, Group 2, n = 21) under standardized conditions. The incidence of technical difficulties and postoperative complaints, onset time of analgesia at the level of T10 and dose requirement of plain bupivacaine 0.5% were recorded. ⋯ While 40% of the catheters were found in a caudal position in Group 1, all catheters were in a cranial position or at the level of the puncture site in Group 2 (P < 0.05). There was no difference in the incidence of postoperative complaints between the groups. The faster onset of analgesia and lower dose requirement of local anaesthetics associated with a lower incidence of technical problems suggest that there is greater effectiveness and safety when microcatheters are inserted using directional needles rather than non-directional needles.
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of 26-gauge Atraucan and 25-gauge Whitacre needles: insertion characteristics and complications.
Ninety-six women undergoing post-partum tubal ligation under spinal anaesthesia were studied to compare 26G Atraucan with 25G Whitacre spinal needles for ease of insertion, number of attempts at needle insertion, cerebrospinal fluid (CSF) flow characteristics through the needles, quality of subsequent analgesia, and incidence of perioperative complications. A higher rate of successful dural puncture at the first attempt (40/50 vs 27/46, P < 0.05) and faster (mean +/- SD, 11.5 +/- 2.2 vs 13.5 +/- 2.4, P < 0.001) CSF flow through the needle was achieved with the Atraucan than with the Whitacre needle. The incidence of failed spinal (4% vs 5%) and post-dural puncture headache (PDPH) (4% vs 4.3%) was similar with both needles, but more patients experienced paraesthesiae during needle insertion with the Whitacre than with the Atraucan needle (15% vs 2%, P < 0.05). We conclude that the use of the 26G Atraucan needle is associated with a higher rate of successful identification of the subarachnoid space at the first attempt, faster CSF backflow, and fewer paraesthesia when compared with the 25G Whitacre needle.
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Randomized Controlled Trial Comparative Study Clinical Trial
Sedative and ventilatory effects of midazolam infusion: effect of flumazenil reversal.
The purpose of this study was to evaluate the effects of flumazenil (1 mg i.v.) on the ventilatory response of premedicated patients receiving a continuous infusion of midazolam for sedation. After assessing baseline ventilatory function using a modified Read rebreathing method for determining hypercapnic ventilatory drive, 16 healthy outpatients were administered fentanyl, 50 micrograms i.v., and midazolam 2 mg i.v., followed by a variable-rate midazolam infusion, 0.3-0.5 mg.min-1. Upon termination of the midazolam infusion, serum midazolam concentrations were measured and ventilatory function was reassessed. ⋯ In some patients, the ventilatory response to hypercarbia actually decreased after flumazenil administration compared with the immediate prereversal (sedated) values. It is concluded that midazolam infusion, 0.43 mg.min-1, did not impair CO2-responsiveness. Flumazenil's effect on central ventilatory drive was more variable than its reversal of midazolam-induced sedation.
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Randomized Controlled Trial Clinical Trial
Gastric fluid volume and pH after nizatidine in adults undergoing elective surgery: influence of timing and dose.
We conducted a prospective, randomized, double-blind study to investigate the effect of oral nizatidine (150-600 mg), a new potent H2 antagonist, on preoperative gastric fluid pH and volume in adults undergoing elective surgery. One hundred and seventy-five healthy adults (21-68 yr) were randomly allocated to seven treatment groups (n = 25); Placebo was administered at 21:00 and 06:30 the night before and on the day of surgery, respectively (0/0: control); nizatidine 150 mg at 21:00 and placebo at 06:30 (150/0); placebo at 21:00 and nizatidine 150 mg at 06:30 (0/150); nizatidine 150 mg at 21:00 and 06:30 (150/150); nizatidine 300 mg at 21:00 and placebo at 06:30 (300/0); placebo at 21:00 and nizatidine 300 mg at 06:30 (0/300); and nizatidine 300 mg at 21:00 and 06:30 (300/300). Each patient fasted overnight and took the drug and/or placebo with 20 ml water. ⋯ The 150/0 group failed to decrease gastric fluid volume and increase pH. In the 300/0 group, the gastric pH was lower than other regimens which effectively decreased gastric acidity (P < 0.05). The number of patients with a pH < 2.5 and a volume > 0.4 ml.kg-1 in the 0/150, 150/150, 0/300, and 300/300 groups (0%) was less than in the control group (16%) (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)