Anesthesia and analgesia
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Anesthesia and analgesia · Feb 2005
Randomized Controlled Trial Clinical TrialOptimal timing of acustimulation for antiemetic prophylaxis as an adjunct to ondansetron in patients undergoing plastic surgery.
We designed this study to evaluate the antiemetic efficacy of transcutaneous electrical acupoint stimulation in combination with ondansetron when applied before, after, or both before and after plastic surgery. A randomized, double-blind, sham-controlled study design was used to compare three prophylactic acustimulation treatment schedules: preoperative--an active device was applied for 30 min before and a sham device for 72 h after surgery; postoperative--a sham device was applied for 30 min before and an active device for 72 h after surgery; and perioperative--an active device was applied for 30 min before and 72 h after surgery (n = 35 per group). All patients received a standardized general anesthetic, and ondansetron 4 mg IV was administered at the end of surgery. ⋯ Finally, patient satisfaction with the quality of recovery (83 +/- 16 and 85 +/- 13 vs 72 +/- 18) and antiemetic management (96 +/- 9 and 94 +/- 10 vs 86 +/- 13) on an arbitrary scale from 0 = worst to 100 = best was significantly higher in the groups receiving peri- or postoperative (versus preoperative) acustimulation therapy. For patients discharged on the day of surgery, the time to home readiness was significantly reduced (114 +/- 41 min versus 164 +/- 50 min; P < 0.05) when acustimulation was administered perioperatively (versus preoperatively). In conclusion, acustimulation with the ReliefBand was most effective in reducing postoperative nausea and vomiting and improving patients' satisfaction with their antiemetic therapy when it was administered after surgery.
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Anesthesia and analgesia · Feb 2005
Circumferential adjustment of ultrasound probe position to determine the optimal approach to the internal jugular vein: a noninvasive geometric study in adults.
Circumferential adjustment of the position of a two-dimensional ultrasound (US) probe around the neck has been recommended as a strategy for reducing the potential for unintentional common carotid artery puncture during internal jugular venous (IJV) cannulation. We obtained multiple high-resolution US images bilaterally from the necks of 107 adult subjects and analyzed these to determine the degree to which this strategy permits identification of a pathway from the skin to the IJV that minimizes venoarterial overlap while maximizing venous target (angular) width. The method consistently permitted identification of an approach to the IJV superior to that obtainable with any one of four popular surface anatomy-based ("blind") approaches and was even more powerful if used in concert with a US-guided 1) adjustment of the degree of head rotation, 2) choice between a high and low approach, and 3) choice between the right and left IJV. Use of a high-resolution US imaging device also permitted identification of the precise boundaries of additional cervical anatomic structures (nontarget vessels, lymph nodes, and the thyroid gland) potentially relevant to selection of an optimal approach to the IJV.
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Anesthesia and analgesia · Feb 2005
Comparative StudyThe ProSeal has a shorter life-span than the Classic laryngeal mask airway.
We tested the hypothesis that the life-span of the ProSeal laryngeal mask airway (LMA) is shorter than the Classic LMA. We also compared residual cuff volumes and changes in elastance and permeability with use. Six new size 4 ProSeal LMAs and 6 new size 4 Classic LMAs were tested. ⋯ The residual cuff volume was higher for the ProSeal LMA (2.6 +/- 1.3 mL versus 1.5 +/- 0.9, P = 0.04). We conclude that the life-span of the ProSeal LMA is shorter than the Classic LMA, but both exceed the manufacturer's recommendations of 40 uses. We recommend that reusable LMA devices be discarded when they fail the pre-use check tests, rather than after a specific number of uses.
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Anesthesia and analgesia · Feb 2005
Large concentrations of nitrous oxide decrease the isoflurane minimum alveolar concentration sparing effect of morphine in the rat.
Many adjuvant drugs have demonstrated anesthetic-sparing properties when combined with volatile anesthetics. Nitrous oxide is combined with volatile anesthetics to reduce the concentrations of volatile anesthetics required to produce anesthesia. Analgesic doses of opioids clearly reduce the requirement for inhaled anesthetics in both human patients and experimental animals. ⋯ The administration of morphine reduced the MAC(ISO) when used with 0% or 30% nitrous oxide. This MAC(ISO) by morphine reduction was less with 50% nitrous oxide and nonexistent at 70% nitrous oxide. However, with morphine present the MAC(ISO) was independent of the nitrous oxide concentration in the 30%-70% range.