Anaesthesia and intensive care
-
Anaesth Intensive Care · Sep 2010
Randomized Controlled Trial Comparative StudyComparison of automated intermittent low volume bolus with continuous infusion for labour epidural analgesia.
Delivery of local anaesthetics via automated intermittent bolus has been shown to improve epidural analgesia compared to delivery via continuous epidural infusion. However the optimal bolus volume has not been investigated. This randomised, double-blind study compared the analgesic efficacy of automated intermittent bolus (volume 2.5 ml every 15 minutes) with that of a continuous epidural infusion (10 ml/hour) for the maintenance of labour epidural analgesia, to determine whether the advantages previously demonstrated for automated intermittent bolus over continuous epidural infusion are retained at this low bolus volume. ⋯ The primary study outcome was the incidence of pain during labour that required management with supplemental epidural analgesia. There were no significant differences between the two regimens in terms of breakthrough pain (automated intermittent bolus 36% [9/25] vs continuous epidural infusion 32% [8/25], P = 0.77). At the doses used in this study, maintenance of labour analgesia using automated intermittent bolus at a bolus volume of 2.5 ml every 15 minutes does not decrease the incidence of breakthrough pain or improve analgesic efficacy compared to continuous epidural infusion.
-
Anaesth Intensive Care · Sep 2010
ReviewInformed consent for anaesthesia in Australia and New Zealand.
The legal and ethical requirements related to an anaesthetist's communication with patients in preparing them for anaesthesia, assisting them in making appropriate decisions and obtaining consent in a formal sense are complex. Doing these things well takes time, skill and sensitivity. The primary focus should be to adequately prepare patients for surgery and to ensure that they are sufficiently well informed to make the choices that best meet their own needs. This is just an affirmation of the importance of patient-centred care.
-
Anaesth Intensive Care · Sep 2010
ReviewFocused transthoracic echocardiography in the perioperative period.
Ultrasound applications in perioperative medicine have expanded enormously over the past decade. Transoesophageal echocardiography has been performed by anaesthetists during cardiac surgery for over 20 years. With the increasing availability of portable ultrasound systems, the use of ultrasound to assist in vascular cannulation and regional anaesthesia has been well described. ⋯ It can help distinguish undifferentiated systolic murmurs preoperatively, give valuable information on the aetiology of unexplained hypotension and cardiovascular collapse and assess response to therapeutic interventions such as vasoactive drugs and volume resuscitation. Focused transthoracic echocardiography should include qualitative assessment of left and right ventricular function, an estimate of aortic valve gradient, right ventricular systolic pressure and intravascular volume status as minimum requirements. Transthoracic echocardiography is a valuable tool in the perioperative period and ideally the equipment and expertise should be available in all operating rooms.
-
Preventive analgesia is defined as the persistence of the analgesic effects of a drug beyond the clinical activity of the drug. The N-methyl D-aspartate receptor plays a critical role in the sensitisation of pain pathways induced by injury. Nitrous oxide inhibits excitatory N-methyl D-aspartate sensitive glutamate receptors. ⋯ However, patients who received nitrous oxide had a shorter duration of patient-controlled analgesia use (nitrous group 35 hours, no nitrous group 51 hours, mean difference -16 hours, 95% confidence interval -29 to -2 hours, P = 0.022). There was no difference in pain scores between the groups. The shorter patient-controlled analgesia duration in the nitrous oxide group suggests that intraoperative nitrous oxide may have a preventive analgesic effect.
-
Anaesth Intensive Care · Sep 2010
Randomized Controlled TrialThe effect of remote ischaemic preconditioning on myocardial injury in patients undergoing off-pump coronary artery bypass graft surgery.
In several recent clinical trials on cardiac surgery patients, remote ischaemic preconditioning (RIPC) showed a powerful myocardial protective effect. However the effect of RIPC has not been studied in patients undergoing off-pump coronary artery bypass graft surgery. We evaluated whether RIPC could induce myocardial protection in off-pump coronary artery bypass graft surgery patients. ⋯ Although RIPC reduced the total amount of troponin I (area under the curve of troponin increase) by 26%, it did not reach statistical significance (RIPC group 53.2 +/- 72.9 hours x ng/ml vs control group 67.4 +/- 97.7 hours x ng/ml, P = 0.281). In this study, RIPC by upper limb ischaemia reduced the postoperative myocardial enzyme elevation in off-pump coronary artery bypass graft surgery patients, but this did not reach statistical significance. Further study with a larger number of patients may be needed to fully evaluate the clinical effect of RIPC in off-pump coronary artery bypass graft surgery patients.