In the Intraoperative Hypothermia for Aneurysm Surgery Trial, neither systemic hypothermia nor supplemental protective drug affected short- or long-term neurologic outcomes of patients undergoing temporary clipping.

Ropivacaine exhibits less cardiotoxicity and causes less motor block than bupivacaine when used in equianalgesic doses. This makes ropivacaine potentially well suited for epidural infusion for postoperative analgesia. The aim of this study was to determine which of three concentrations of epidurally administered ropivacaine infused for postoperative analgesia would attenuate intravenous opioid analgesia requirements while also minimizing motor block. Forty ASA I-III patients, having major lower abdominal surgery, completed the study. They were randomly assigned to one of four treatment groups: Group S, control, epidural saline (n = 10); Group 1, epidural 0.1% ropivacaine (n = 10); Group 2, epidural 0.2% ropivacaine (n = 10); and Group 3, epidural 0.3% ropivacaine (n = 10). The study was double-blind. Initial epidural analgesia was established with 0.5% ropivacaine, and then general anesthesia induced for surgery. Once in the recovery room, epidural infusions were commenced at 10 mL/h and maintained at that rate for 21 h. Intravenous patient controlled analgesia (PCA) morphine was used as required by the patients for supplemental analgesia. Total PCA morphine use was more over the 21-h period in Group S than all the ropivacaine groups, being significantly so for Group 2 (median values: Group S, 43.3 mg; Group 1, 18.7 mg; Group 2, 7.5 mg; Group 3, 19 mg; for Group 2, P = 0.03). Visual analog scale (VAS) scores on coughing were significantly lower (i.e., less pain) than control for all ropivacaine groups after 4 h of infusion and also for Groups 2 and 3 after 8 h of infusion. (Median VAS (mm) on coughing at 8 h: Group S = 70, Group 1 = 56, Group 2 = 32, Group 3 = 0; for Groups 2 and 3, P < 0.05 compared to Group S). There was a dose-related increase in the amount of motor block, with Group 3 having significantly more motor block than all other groups at 4 and 8 h.(ABSTRACT TRUNCATED AT 250 WORDS)

A new 'texturing method' has been developed for nerve block needles in an attempt to improve the ultrasonic image of the needles. Using a synthetic phantom, these textured needles were compared to currently available needles. The textured needle had improved visibility under ultrasound. This type of needle may assist the anaesthetist perform ultrasound-guided regional anaesthesia.

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Background Perioperative hypothermia has been reported to increase the occurrence of cardiovascular complications. By increasing sympathetic nervous system activity, perioperative hypothermia also has the potential to increase cardiac injury and dysfunction associated with subarachnoid hemorrhage. Methods The Intraoperative Hypothermia for Aneurysm Surgery Trial randomized patients undergoing cerebral aneurysm surgery to intraoperative hypothermia (n = 499, 33.3 ± 0.8°C) or normothermia (n = 501, 36.7 ± 0.5°C). Cardiovascular events (hypotension, arrhythmias, vasopressor use, myocardial infarction, etc.) were prospectively followed until 3 month follow-up and were compared between hypothermic and normothermic patients. A subset of 62 patients (hypothermia, n = 33; normothermia, n = 29) also had preoperative and postoperative (within 24 h) measurement of cardiac troponin-I and echocardiography to explore the association between perioperative hypothermia and subarachnoid hemorrhage-associated myocardial injury and left ventricular function. Results There was no difference between hypothermic and normothermic patients in the occurrence of any single cardiovascular event or in composite cardiovascular events. There was no difference in mortality (6%) between groups and there was only a single primary cardiovascular death (normothermia). There was no difference between hypothermic and normothermic patients in post- vs. preoperative left ventricular regional wall motion or ejection fraction. Compared with preoperative values, hypothermic patients had no postoperative increase in cardiac troponin-I (median change 0.00 μg/L) whereas normothermic patients had a small postoperative increase (median change + 0.01 μg/L, P = 0.038). Conclusion In patients undergoing cerebral aneurysm surgery, perioperative hypothermia was not associated with an increased occurrence of cardiovascular events.

Background We explored the relationship between nitrous oxide use and neurological and neuropsychological outcome in a population of patients likely to experience intraoperative cerebral ischemia: i.e., those who had temporary cerebral arterial occlusion during aneurysm clipping surgery. Methods A post hoc analysis of a subset of the data from the Intraoperative Hypothermia for Aneurysm Surgery Trial was conducted. Only subjects who had temporary arterial occlusion during surgery were included in the analysis. Metrics of short-term and long-term (i.e., 3 months post-surgery) outcome were evaluated via both univariate and multivariate logistic regression analysis. An odds ratio (OR) of greater than 1.0 denotes a worse outcome in patients receiving nitrous oxide. Results We evaluated 441 patients, of which 199 received nitrous oxide. Patients receiving nitrous oxide had a greater risk of delayed ischemic neurologic deficits (i.e., the clinical manifestation of vasospasm) (OR=1.78, 95% confidence interval [CI]=1.08–2.95, p=0.025). However, at 3 months after surgery, there was no difference in any metric of gross neurologic outcome: Glasgow Outcome Score (OR=0.67, CI=0.44–1.03, p=0.065), Rankin Score (OR=0.74, CI=0.47–1.16, p=0.192), National Institutes of Health Stroke Scale (OR=1.02, CI=0.66–1.56, p=0.937), or Barthel’s Index (OR=0.69, CI=0.38–1.25, p=0.22). The risk of impairment on at least one test of neuropsychological function was reduced in those who received nitrous oxide (OR=0.56, CI=0.36–0.89, p=0.013). Conclusion In our patient population, use of nitrous oxide was associated with an increased risk for the development of delayed ischemic neurologic deficits; however, there was no evidence of detriment to long-term gross neurologic or neuropsychological outcome.

Major international bodies recommend that adults should accumulate at least 30 minutes of moderate intensity physical activity every day. Ten thousand steps a day has been found to approximate 30 minutes of exercise. A questionnaire regarding exercise patterns was sent to all (584) Victorian consultant anaesthetists, and 30 consultants wore a pedometer for one week, during working hours only. The questionnaire response rate was 59.4% (347). Of these respondents, 58% indicated that they had a formal exercise program. There were no significant differences between people with a set exercise program and those without, with respect to age, gender, working hours or smoking. Those with a set exercise program exercised a median of four times per week and the commonest exercise listed was gymnasium attendance (40%). The main reasons cited for having a regular exercise program were maintenance of physical health (77%), mental health (71%) and weight control (35%). The main reasons for not having an exercise program were fatigue (40%), too busy (70%), family commitments (67%) or just not interested (18%). The overall median steps per day for the pedometer group was 4770 with a range of 1667 to 9630, fitting into the classification of 'sedentary'. In summary this study has shown that a significant number of anaesthetists do not achieve adequate physical activity in or out of working hours and has identified some reasons for this behaviour. This will hopefully provide motivation and information for the implementation of useful strategies to increase the level of physical activity performed by anaesthetists.

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