Canadian journal of anaesthesia = Journal canadien d'anesthésie
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During hypothermic cardiopulmonary bypass (CPB) patients are cooled, usually to between 30-32 degrees C, and, after myocardial blood flow is restored, they are rewarmed with blood heated in the pump-oxygenator. We audited our local practice by recording tympanic and nasopharyngeal temperatures in 11 patients undergoing hypothermic CPB. ⋯ This may be of some importance because it has become widely appreciated by neuroscientists that mild degrees of brain cooling (2-5 degrees C) are capable of conferring dramatic protection from ischaemic brain injury and, conversely, mild temperature elevation may be markedly deleterious. If control of brain temperature is considered desirable then we would suggest that nasopharyngeal temperature be monitored during rewarming on CPB.
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Twenty adult male patients undergoing anorectal surgery in the jackknife position under spinal anaesthesia were studied for the anaesthetic properties of 5 ml hypobaric 0.1% bupivacaine. The patients were positioned in the prone, jack-knife position with a pillow under the hips and with an operating table break angulation of 30 degrees with head down tilt of 20 degrees. In this position a 25-gauge Quincke spinal needle was inserted intrathecally through L3-4 and 5 ml solution, prepared by mixing 1 ml bupivacaine 0.5% with 4 ml of distilled water with a specific gravity of 1.001 at 20 degrees C, was given over 15-20 sec. ⋯ The average duration of postoperative analgesia was 339.5 +/- 182.9 min. Post-spinal headache was not observed in any patients. In conclusion, 5 ml intrathecal hypobaric bupivacaine, 0.1%, provided excellent perioperative analgesia without motor blockade and haemodynamic stability in patients undergoing anorectal surgery in jackknife position.
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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.