Preoperative warming using the Bair Paws system results in smaller decreases in core temperature intraoperatively and less IPH in patients undergoing spinal surgery under general anaesthesia.

Summary In this article we will look at some of the principles in processed EEG monitoring as applied to bispectral index (BIS). We outline why BIS should be regarded as a ‘memory’ monitor which in most circumstances reflects the depth of sedation or anaesthesia in particular patients. Its limitation in paralysed and non‐paralysed patients must be understood in order for this monitor to be used safely. Finally, its emerging use in critical care will be explored.

SummaryEight patients were given a propofol infusion until they no longer responded to loud verbal stimuli, a sedation score of two (modified Observer Assessment of Alertness and Sedation Scale). After receiving 15 mg of intravenous epinephrine, changes in sedation score and bispectral index (BIS) were observed. Mean pulse rate increased from 68 to 96 (SD 10) beat.min 21 , mean blood pressure increased from 107/60 (SD 10/8) mmHg to 140/70 (SD 27/14) mmHg, and mean BIS level rose from 63 to 76 (p , 0.005). Sedation scores increased in six of the eight patients. Exogenous catecholamines seem to have an arousal effect on lightly anaesthetised patients. This could be due to changes in neurotransmitter levels in the brain, or due to the effects consequent on increased cardiac output.

In this study, the Macintosh laryngoscope outperformed the other devices. However, the Glidescope was considered easy to use regardless of previous experience and was the preferred device for the simulated difficult airway.

Initial evaluation suggests that ePAQ is acceptable to patients. Data collected using the system were found to be reliable, and its intrinsic scoring systems for ASA and BMI are comparable with values assigned by clinicians.

No abstract

SummaryWe compared the effect of delivering fluid warmed using two methods in 76 adult patients having short duration surgery. All patients received a litre of crystalloid delivered either at room temperature, warmed using an in-line warming device or pre-warmed in a warming cabinet for at least 8 h. The tympanic temperature of those receiving fluid at room temperature was 0.4°C lower on arrival in recovery when compared with those receiving fluid from a warming cabinet (p = 0.008). Core temperature was below the hypothermic threshold of 36.0°C in seven (14%) patients receiving either type of warm fluid, compared to eight (32%) patients receiving fluid at room temperature (p = 0.03). The administration of 1 l warmed fluid to patients having short duration general anaesthesia results in higher postoperative temperatures. Pre-warmed fluid, administered within 30 min of its removal from a warming cabinet, is as efficient at preventing peri-operative hypothermia as that delivered through an in-line warming system. Unintended peri-operative hypothermia (defined as a peri-operative core temperature < 36.0°C) is a common problem [1,2]. Known complications attributed to perioperative hypothermia include an increased incidence of myocardial ischaemia, wound infections, and coagulopathies. Peri-operative hypothermia is also associated with prolonged hospital stay and increased hospital costs [3][4][5]. Thermal redistribution occurs following induction of anaesthesia and accounts for a drop in core temperature of up to 1.6°C [2]. Although forced-air warming devices can effectively restore core temperature within 2 h [6,7], the physiology of thermal redistribution often renders them inadequate for procedures of short duration [8]. The recently published National Institute for Health and Clinical Excellence (NICE) guidelines on prevention of peri-operative hypothermia advise that all fluid (and blood products) delivered to patients having anaesthesia of any duration should be warmed to 37.0°C [9,10].Most fluid warming techniques involve the use of disposable equipment and hardware [11]. Fluid warming cabinets are installed in many theatres. A bench study has demonstrated that fluid previously warmed in a warming cabinet has the potential to be as effective in limiting the effect of peri-operative hypothermia as 'in-line' warming systems [12].The aims of this study were to examine the difference in core temperatures of patients following delivery of 1 l pre-warmed intravenous fluid taken from a warming cabinet compared with delivery of 1 l fluid via a commercial in-line warmer. We also wanted to observe the incidence of postoperative hypothermia following administration of 1 l warmed fluid, when compared with fluid administered at room temperature. MethodsThe study was granted approval by the local research ethics committee. Written informed consent was obtained from 82 adult patients of ASA physical status 1-2 who were scheduled to undergo general anaesthesia for Anaesthesia, 2010, 65, pages 942-945

Pre-operative anxiety is an unpleasant state of psychological distress that occurs in up to 87% of patients awaiting neurosurgical procedures. Sedative medication is undesirable in this population due to the need for early postoperative neurological assessment. Acupuncture has previously been shown to reduce pre-operative anxiety, but studies involving neurosurgical patients are lacking. This single-centre, prospective, randomised controlled trial was designed to determine the effect of acupuncture at the EX-HN3 (Yintang point) on pre-operative anxiety levels in neurosurgical patients. The study was prospectively registered before participant recruitment. After measuring baseline anxiety levels, 128 patients were randomly allocated in a 1:1 ratio by a web-based computer program to receive either acupuncture at the EX-HN3 (Yintang) point (acupuncture group) or no intervention (control group). Participants were not blinded, but all analyses were performed by a member of the research team who was unaware of the group allocation. The primary outcome measure was anxiety level after 30 min, as measured by the six-item short form of the State-Trait Anxiety Inventory (possible score range 20-80). Sixty-two patients in each group were subsequently analysed. Median (IQR [range]) anxiety State-Trait Anxiety Inventory score reduced significantly in the acupuncture group (46.7 (36.7-53.3 [23.3-70.0]) to 40.0 (30.0-46.7) [20.0-53.3]), p < 0.001), with no change seen in the control group (41.7 (33.3-53.3 [20.0-76.7]) to 43.3 (36.7-50.0 [20.0-76.7]), p = 0.829). There were no adverse events in either group. Acupuncture at the EX-HN3 point reduces pre-operative anxiety levels in patients awaiting neurosurgery.