Anaesthesia and intensive care
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Anaesth Intensive Care · Jan 2013
Randomized Controlled TrialEpidural anaesthesia with goal-directed administration of ropivacaine improves haemodynamic stability when combined with general anaesthesia in elderly patients undergoing major abdominal surgery.
The use of epidural ropivacaine may result in significant haemodynamic fluctuations during combined epidural and general anaesthesia. We designed this study to investigate whether epidural anaesthesia with a goal-directed approach, when combined with general anaesthesia, improved haemodynamic stability in elderly patients undergoing major abdominal surgery. Seventy-five elderly patients undergoing major abdominal surgery were randomly and evenly assigned to one of three groups receiving intraoperative epidural anaesthesia with either ropivacaine 0.1% (Group 1), ropivacaine 0.375% (Group 2) or ropivacaine 0.375% for abdominal wall pain and ropivacaine 0.1% for visceral pain (Group 3). ⋯ The need for vasoactive drug administrations was 1.4 (standard deviation 0.9) in Group 3 (n=24), representing a significantly lower frequency of administration compared with Groups 1 (n=24) and 2 (n=24) (P <0.05 versus Group 1; P <0.01 versus Group 2). The total intraoperative dose of remifentanil was significantly greater in Group 1 (P <0.01 versus Group 2; P <0.05 versus Group 3) but did not differ significantly between Groups 2 and 3. Goal-directed epidural anaesthesia with different ropivacaine concentrations can improve haemodynamic stability when combined with general anaesthesia for elderly patients undergoing major abdominal surgery.
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Anaesth Intensive Care · Nov 2012
Randomized Controlled Trial Comparative StudyA pilot study of cerebral and haemodynamic physiological changes during sedation with dexmedetomidine or propofol in patients with acute brain injury.
Sedation for the mechanically-ventilated, brain-injured patient remains challenging. The purpose of this pilot study was to compare the cerebral physiologic effects of sedation with propofol versus dexmedetomidine in mechanically-ventilated, brain-injured patients. Using a randomised, crossover, unblinded clinical trial, we enrolled patients with severe brain injury (Glasgow Coma Score ≤8) from traumatic injury, subarachnoid haemorrhage or intracerebral haemorrhage undergoing multimodal monitoring (intracranial pressure, brain temperature, oximetry and microdialysis). ⋯ Though differences were noted in cerebral metabolic substrates (lactate/pyruvate ratio), none were statistically significant. In our pilot cohort, dexmedetomidine and propofol appear equally effective in sedating severely brain-injured patients and neither is associated with adverse physiological effects as measured by multimodal monitoring. Larger long-term studies are required to determine whether clinically favourable benefits demonstrated in the medical critical care setting also apply to this patient population.
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Anaesth Intensive Care · Nov 2012
Randomized Controlled Trial Comparative StudyFifteen-hour day shifts have little effect on the performance of taskwork by anaesthesia trainees during uncomplicated clinical simulation.
Shiftwork and work-hour limits for junior doctors are now well established in hospital work patterns. In order to ensure that trainees have adequate exposure to daytime elective surgical procedures, there is a tendency to have long shifts that include an after-hours component. However, long shifts can cause performance decrement due to time-on-task fatigue. ⋯ In both conditions, there was failure to meet current guidelines for preoperative evaluation or machine check, and when fatigued there was a 'trend' (P=0.06) to a reduction in the number of items in the machine check. With increase in time awake, there was an increase in time taken for explanation to the patient, an increase in mean duration of explanation to the patient, more time looking at the intravenous line or fluids when multi-tasking but less time adjusting the intravenous fluid. These effects are minor during routine uncomplicated induction of anaesthesia, but further investigation is needed to examine fatigue effects during non-routine circumstances.
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Anaesth Intensive Care · Nov 2012
Randomized Controlled Trial Comparative StudyEffects of a 1:1 inspiratory to expiratory ratio on respiratory mechanics and oxygenation during one-lung ventilation in the lateral decubitus position.
Prolonged inspiratory to expiratory (I:E) ratio ventilation may have both positive and negative effects on respiratory mechanics and oxygenation during one-lung ventilation (OLV), but definitive information is currently lacking. We therefore compared the effects of volume-controlled ventilation with I:E ratios of 1:1 and 1:2 on respiratory mechanics and oxygenation during OLV. Fifty-six patients undergoing thoracoscopic lobectomy were randomly assigned volume-controlled ventilation with an I:E ratio of 1:1 (group 1:1, n=28) or 1:2 (group 1:2, n=28) during OLV. ⋯ There were no significant differences in PaO2 during OLV between the two groups (OLV30, P=0.856; OLV60, P=0.473). In summary, volume-controlled ventilation with an I:E ratio of 1:1 reduced peak and plateau airway pressures improved dynamic compliance and efficiency of alveolar ventilation, but it did not improve arterial oxygenation in a substantial manner. Furthermore, the associated increase in mean airway pressure might have reduced cardiac output, resulting in a lower central venous oxygen saturation.
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Anaesth Intensive Care · Sep 2012
Randomized Controlled TrialEffect of preoperative education on behaviour of children during induction of anaesthesia: a randomised clinical trial of efficacy.
In this randomised prospective study we aimed to evaluate whether preoperative anaesthetic education delivered to children on the day of surgery reduces anxiety behaviour during induction of anaesthesia. One hundred children, six to 15 years of age, undergoing general anaesthesia for ambulatory surgery were allocated at random to a preoperative education group (n=50) or a control group (n=50). The main outcomes were behaviour score, self-reporting of satisfaction score and identification of the stage when children felt most fearful. ⋯ Intravenous induction failed in nine out of 38 children in the intervention group (23.7%) compared to five out of 40 in the control group (12.5%). When intravenous induction failed, eight out of nine (89%) of the intervention group remained co-operative during gas induction compared to two out of five (40%) of the control group. Preoperative education delivered on the day of surgery did not reduce anxiety behaviour in children during intravenous induction of anaesthesia, but did reduce anxiety during subsequent inhalational induction.