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We studied 30 children undergoing circumcision randomly allocated to receive either thiopentone 4 mg.kg-I , propofol2.5 mg.kg-I or midazolam 0.5 mg.kg-I (n=JO) IV over 30 seconds at induction of anaesthesia. Blood pressure and pulse rate during the first 15 minutes of induction were recorded by a Finapres 2300e and a Cardiocap CM-J04, and changes from preinduction baseline compared between the three induction agents and the two recording instruments. Postoperatively, blood levels of the induction agents were measured and recovery from anaesthesia was assessed by clinical criteria, mood and sedation scores and psychomotor performance. The Cardiocap data revealed no statistically significant haemodynamic differences between the three induction agents. Finapres data demonstrated that propofol caused a greater decrease in mean arterial pressure when compared to thiopentone at one minute (P=0.01) and the MAP remained significantly lower than midazolam at five minutes (P= 0.02), illustrating an advantage of continuous over intermittent non-invasive blood pressure monitoring. The midazolam group took longer to identify themselves compared to both the propofol (P= 0.005) and the thiopentone groups (P=0.02), but there was no difference in the groups in time to eye-opening. Psychomotor performance on awakening was significantly worse in the midazolam group compared to the propofol (P< 0.03) and thiopentone groups (P< 0.02). Most children had recovered to 80% of their best, practised, unmedicated, preoperative performance four hours after awakening, irrespective of the induction agent administered. Drug blood levels correlated weakly with both methods of psychomotor assessment (r ~ 0.6). Of the three induction agents, thiopentone caused the least haemodynamic perturbation on induction, and anaesthesia induced with midazolam caused the greatest psychomotor impairment on awakening. Within one hour patients in all drug groups were equally awake, co-operative and co-ordinated.

General anaesthesia for obstetric surgery has distinct characteristics that may contribute towards a higher risk of accidental awareness during general anaesthesia. The primary aim of this study was to investigate the incidence, experience and psychological implications of unintended conscious awareness during general anaesthesia in obstetric patients. From May 2017 to August 2018, 3115 consenting patients receiving general anaesthesia for obstetric surgery in 72 hospitals in England were recruited to the study. Patients received three repetitions of standardised questioning over 30 days, with responses indicating memories during general anaesthesia that were verified using interviews and record interrogation. A total of 12 patients had certain/ probable or possible awareness, an incidence of 1 in 256 (95%CI 149-500) for all obstetric surgery. The incidence was 1 in 212 (95%CI 122-417) for caesarean section surgery. Distressing experiences were reported by seven (58.3%) patients, paralysis by five (41.7%) and paralysis with pain by two (16.7%). Accidental awareness occurred during induction and emergence in nine (75%) of the patients who reported awareness. Factors associated with accidental awareness during general anaesthesia were: high BMI (25-30 kg.m -2 ); low BMI (<18.5 kg.m -2 ); out-of-hours surgery; and use of ketamine or thiopental for induction. Standardised psychological impact scores at 30 days were significantly higher in awareness patients (median (IQR [range]) 15 (2.7-52.0 [2-56]) than in patients without awareness 3 (1-9 [0-64]), p = 0.010. Four patients had a provisional diagnosis of post-traumatic stress disorder. We conclude that direct postoperative questioning reveals high rates of accidental awareness during general anaesthesia for obstetric surgery, which has implications for anaesthetic practice, consent and follow-up.

We have compared the incidence of preoperative and postoperative oxygen desaturation in 20 elderly patients undergoing dynamic hip screw insertion for fractured neck of femur, allocated randomly to two groups to receive subarachnoid anaesthesia (SA, n = 10) or a general anaesthetic (GA, n = 10). Oximetry data were recorded during the preoperative night and the first 48 hours after surgery using Satmaster. 1\1 Data associated with zero amplitude signal were automatically invalidated by the software and decreases in Sp02 which were preceded by contemporaneous changes in signal amplitude which conformed to a previously described template were assumed to be artefactual and were discarded from final data analysis. Data demonstrated a wide interpatient variability. However, those patients who desaturated preoperatively continued to do so in the postoperative period. The differences between the preoperative and postoperative oximetry profiles were examined for each patient and demonstrated a significantly longer time spent with Sp02 <90% in the GA group compared with the SA group, in all the recorded time periods, except on the day of surgery. The SA group showed an improvement in oxygen saturation postoperatively when compared to the preoperative night, spending less time with an Sp02 <85%. We conclude that the subarachnoid anaesthetic technique was associated with a lower incidence of postoperative oximetry desaturation when compared with general anaesthetic for these elderly patients undergoing repair of fractured neck of femur.

We studied 30 children, aged 4 to 12 years, undergoing elective circumcision, premedicated with midazolam 0.5 mg.kg-I and atropine 0.02 mg.kg-I by mouth. A modified postbox test and the coding component of the Wechsler intelligence scale (WISC-R) was used to assess the preoperative effect of premedication on psychomotor function. Mood and sedation were also scored and related to serum midazolam concentrations. The children showed a significant decline in psychomotor performance 30 and 60 minutes after premedication when compared with their best un medicated performance recorded the previous evening. This decline in psychomotor performance was only weakly associated with serum midazolam concentrations (r = 0.1). The postbox toy ratio is a suitable measurement of psychomotor performance in children because of its simplicity and ease of use in the clinical environment, although it may suffer the "test-retest" limitations of similar types of assessment. The sedative and anxiolytic effects of midazolam provide a quiet environment for a smooth induction of anaesthesia.

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Introduction  For those children having surgery, induction of anaesthesia is one of the most stressful procedures the child experiences perioperatively. Current work has failed to show a benefit of parental presence at induction of anaesthesia for all children. The reasons for lack of effect may include the high anxiety levels of some parents and also that the role for parents at their child's induction is not delineated. The main aim of this study was to see if parental preparation by teaching of distraction techniques could reduce their child's anxiety during intravenous induction of anaesthesia. Methods  After ethics committee approval 40 children aged 2–10 years old, ASA status I or II undergoing daycase surgery under general anaesthesia were enrolled into the study. To avoid possible confounding factors children with a history of previous, surgery, chronic illness or developmental delay were excluded form participation. No children were given sedative premedication. After written informed consent by the parent, each child and parent was randomly assigned to an intervention or control group. Parents in the intervention group received preparation from a play specialist working on the children's surgical ward. It involved preparation for events in the anaesthetic room and instruction on methods of distraction for their child during induction using novel toys, books or blowing bubbles appropriate to the child's age. Preoperative information collected included demographic and baseline data. The temperament of the child was measured using the EASI (Emotionality, Activity, Sociability, Impulsivity) instrument of child temperament(l). In the anaesthetic room all children were planned to have intravenous induction of anaesthesia after prior application of EMLA cream. Anxiety of the child was measured by the modified Yale Preoperative Anxiety Scale (mYPAS)(2) by a blinded independent observer at three time points: entrance to the anaesthetic room, intravenous cannulation and at anaesthesia induction. Cooperation of the child was measured by the Induction Compliance Checklist (ICC) by the same observer (3). Postoperative data collected included parental satisfaction and anxiety scores measured by the Stait Trait Anxiety Inventory (STAI)(4) and at one week the behaviour of the child was measured Using the Posthospitalisation Behavioural Questionnaire (PHBQ)(5). Normally distributed data were analysed by a two‐sample t‐test, categorical data by Pearson's Chi‐squared test and non‐parametric data by the Wilcoxon rank‐sum test. Results  One parent withdrew after enrolment. This left 22 children in the control group and 17 in the intervention group. There were no significant differences in demographic and baseline data of the children between the two groups including ethnic origin, number of siblings, birth order of the child, recent stressful events in the child's life, previous hospital admissions and the temperament of the child. Parent demographics were also similar between groups including parent's age, sex, relationshi...

SummaryBlood pressure measurements associated with malapplication of a finger cuff were compared with contemporaneous intra-arterial pressure data in seven volunteers to determine the influence of cuff application on the accuracy of the Finapres 2300e. Systolic readings in all cuff positions differed from arterial line data by more than the recommended standard and tight and loose cuff applications under and over-read respectively, in all subjects. The results show the Finapres to be sensitive to small degrees of finger cuff malapplication which contribute to the bias on direct arterial comparison and limit the reliability ofthe instrument in clinical practice.