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J A W Wildsmith

Publications and source records attributed to J A W Wildsmith.

At least 19 recordsLinked to original sources

Intermittent vs continuous administration of epidural ropivacaine with fentanyl for analgesia during labour.

BACKGROUND: Many years ago regular intermittent bolus administration of epidural local anaesthetic solution was recognized to produce more effective analgesia than continuous infusion, but only recently has the development of suitable pumps allowed the former technique's wider evaluation. METHODS: In this randomized, double-blind trial, 40 primigravid patients had a lumbar epidural catheter inserted, and plain ropivacaine 0.2% 15-20 ml was titrated until analgesia and bilateral sensory block to T10 were produced (time zero). Patients were then given either an infusion of ropivacaine 2 mg ml(-1) with fentanyl 2 microg ml(-1) at 10 ml h(-1), or hourly boluses of 10 ml of the same solution. Pain, sensory block and motor block were measured frequently. If requested, additional 10 ml boluses of the study mixture were given for analgesia. RESULTS: There were no differences between the two groups in patient characteristics, obstetric/neonatal outcome, or in sensory or motor block. A total of 12 (60%) patients in the continuous group required one or more additional boluses compared with 4 (20%) patients in the intermittent group (95% CI 9.6-61.7%, P=0.02). Therefore the intermittent group received a lower total drug dose than the infusion group (P=0.02). Duration of uninterrupted analgesia (time to first rescue bolus) was longer in the intermittent group (P<0.02). CONCLUSIONS: The intermittent group required fewer supplementary injections and less drug to maintain similar pain scores, sensory and motor block compared with the continuous group. This represents a more efficacious mode of analgesia.

Adult↗

Measuring the quality of continuous epidural block for abdominal surgery.

BACKGROUND: In view of the wide variation in pain experience between patients, a clinical standard -- the time from the end of surgery to the first experience of pain -- was applied to 1359 consecutive patients in order to investigate whether the initial quality of epidural block has an effect on the overall quality of postoperative pain relief. METHODS: Clinical data were recorded in 58,118 out of 72,412 h in 1359 patients, and transferred to a database. Data collected included pain scores on a four-point verbal rating scale; nausea and vomiting; motor block; sedation scores; systolic blood pressure <100 and <90 mm Hg; ventilatory frequency <10 and <8 bpm; and hourly epidural infusion rate. RESULTS: As the time to first experience of pain increased from nil to >24 hours, the time from the first to last experience of pain shortened from 34 (19-50) h to 3 (1-12) h (p<0.001) and the proportion of patients receiving an epidural bolus decreased from 53 to 8% (p<0.001). Increases in the initial pain free time increased the proportion of patients with systolic BP<100 mmHg from 59 to 77%, (p<0.001) and increased the proportion of patients with respiratory rate <10 bpm from 13 to 26%, (p<0.001). CONCLUSION: Extending pain relief for more than 12 h beyond the end of abdominal surgery significantly improves the overall quality of postoperative pain relief, but is associated with an increase in side-effects.

Abdomen↗

Epidural abscesses.

Until recently epidural abscess was considered a rare, almost theoretical, complication of central nerve block, but anecdotal reports suggest that this is no longer the case. Thus a review of the risk factors, pathogenesis, clinical features and outcome of this condition is appropriate, the primary aim being to make recommendations on best anaesthetic practice to minimize the risk of this serious complication. A search of EMBASE(c), PUBMED(c) and MEDLINE(c) databases from 1966 to September 2004 was performed using several strategies, supplemented by reference list screening. Spontaneous epidural abscess is rare, accounting for 0.2-1.2 cases per 10,000 hospital admissions per year. Estimates of the incidence after central nerve block vary from 1:1,000 to 1:100,000. Risk factors (compromised immunity, spinal column disruption, source of infection) are present in the majority of patients, whether the condition is spontaneous or associated with central nerve block. Presentation is vague, fever and back pain usually preceding neurological deficit. Diagnosis requires a high index of suspicion and modern imaging techniques. Treatment involves early surgical drainage to prevent permanent deficit and high dose parenteral antibiotics chosen with bacteriological advice. Primary prevention depends on proper use of full aseptic precautions. Epidural abscess can be a catastrophic consequence of central nerve block. Early diagnosis will minimize permanent damage, but primary prevention should be the aim. There is a need for a large survey to indicate the true incidence to better inform the risk-benefit ratio for central nerve block.

Anesthesia, Epidural↗

Segmental spinal anaesthesia for cholecystectomy in a patient with severe lung disease.

Occasionally patients awaiting heart or lung transplant because of terminal disease require other types of surgery, but present significant challenges to the anaesthetist because of impaired organ function. Regional anaesthesia may have much to offer such patients and we here report one who underwent successfully a laparoscopic cholecystectomy under segmental subarachnoid (spinal) anaesthesia performed at the low thoracic level. The anatomical and physiological consequences of such a technique are discussed.

Anesthesia, Epidural↗

"Doughty" technique.

Explore the source record for details and available documents.

Anesthesia, Epidural↗

Predictors of emotional outcomes of intensive care.

Negative emotional outcomes (anxiety, depression and post-traumatic stress) have been identified in patients discharged from intensive care. The aims of this prospective, longitudinal study were to assess levels of and changes in emotional outcome after intensive care, and to explore how these relate to objective and subjective indicators of the intensive care experience. Emotional outcome was assessed using the Hospital Anxiety and Depression and Impact of Event Scales. Anxiety (p = 0.046) and depression (p = 0.001) were reduced subsequently, but not avoidance (p = 0.340) or intrusion (p = 0.419). Most objective (age, gender, length of ICU and hospital stay) and subjective indicators (as measured by the Intensive Care Experience Questionnaire) of the intensive care experience were related to negative emotional outcome. Subjective interpretation of the intensive care experience emerged as a consistent predictor of adverse emotional outcome, in both the short- and the long-term.

Adult↗

Comparison of plain and hyperbaric solutions of ropivacaine for spinal anaesthesia.

BACKGROUND: Preliminary work has shown that ropivacaine provides spinal anaesthesia of shorter duration than bupivacaine, and may be of particular use in the day-case setting. However, there are few data comparing the actions of plain and hyperbaric solutions of this drug. METHODS: Forty ASA grade I-II patients undergoing elective perineal surgery under spinal anaesthesia were randomized to receive 3 ml ropivacaine 5 mg ml(-1), either in plain solution or with glucose 50 mg ml(-1). The extent and duration of sensory and motor block, pulse rate, blood pressure, and time to mobilization were recorded. RESULTS: Two patients (one per group) were withdrawn because of total block failure. There were significant differences in median time to onset of sensory block at T10 (plain 10 min; hyperbaric 5 min; P<0.01), median maximum extent (plain T8; hyperbaric T4; P<0.05), and median duration of sensory block at T10 (plain 25 min; hyperbaric 115 min; P<0.001). However, median times to complete regression of both sensory (270 vs 240 min; P<0.05) and motor (180 vs 120 min; P<0.001) block were longer in the plain group. Patients therefore mobilized sooner in the hyperbaric group (218 [n=16] vs 286 min [n=17]; P<0.01). All the hyperbaric blocks were adequate for surgery, but three patients receiving plain ropivacaine required general anaesthesia. CONCLUSION: Addition of glucose 50 mg ml(-1) to ropivacaine 5 mg ml(-1) increases the speed of onset, block reliability, duration of useful block for perineal surgery, and speed of recovery. Plain solutions are less reliable for surgery above a dermatomal level of L1.

Adult↗

The interaction of anaesthetic steroids with recombinant glycine and GABAA receptors.

BACKGROUND: Anaesthetic steroids are established positive allosteric modulators of GABAA receptors, but little is known concerning steroid modulation of strychnine-sensitive glycine receptors, the principal mediators of fast, inhibitory neurotransmission in the brain stem and spinal cord. This study compared the modulatory actions of five anaesthetic pregnane steroids and two non-anaesthetic isomers at human recombinant alpha1 glycine and alpha1beta2gamma2L GABAA receptors. METHODS: Recombinant alpha1 glycine or alpha1beta2gamma2L GABAA receptors were expressed in Xenopus laevis oocytes and agonist-evoked currents recorded under voltage-clamp. Steroid modulation of currents evoked by GABA, or glycine, was quantified by determining the potency (EC50) and maximal effect of the compounds. RESULTS: The anaesthetics minaxolone (EC50=1.3 microM), Org20599 (EC50=1.1 microM) and alphaxalone (EC50=2.2 microM) enhanced currents mediated by GABAA receptors. The anaesthetics also enhanced currents mediated by glycine receptors, although with higher EC50 values (minaxolone 13.1 microM; Org20599=22.9 microM and alphaxalone=27.8 microM). The maximal enhancement (to 780-950% of control) produced by the three steroids acting at the GABAA receptor was similar, but currents evoked by glycine were potentiated with increasing effectiveness by alphaxalone (199%) <Org20599 (525%) <minaxolone (1197%). The anaesthetic isomers, 5alpha-pregnan-3alpha-ol-20-one and 5beta-pregnan-3alpha-ol-20-one (eltanolone) enhanced GABAA receptor-mediated currents with similar potency and efficacy, but only the former enhanced glycine, the latter causing inhibition. The non-anaesthetic steroids 5alpha-pregnan-3beta-ol-20-one and 5beta-pregnan-3beta-ol-20-one modulated neither GABAA, nor glycine, receptors. CONCLUSIONS: The data demonstrate that structure-activity relationships for steroid modulation at glycine and GABAA receptors differ. Comparing the EC50 values reported here with free plasma concentrations during steroid-induced anaesthesia indicates that a selective modulation of GABAA receptor activity is likely to occur in vivo.

Anesthetics↗

The intensive care experience: development of the ICE questionnaire.

BACKGROUND: Previous research has shown that patients' reported memories of intensive care are often of unpleasant events which are described as frightening and persecutory in nature. Currently, there is no standardized way of assessing perceptions of such an experience or relating it to long-term outcome. AIMS: This paper describes the development of an intensive care experience questionnaire which aims to (a) identify the domains of such an experience, (b) assess and quantify that experience, and (c) explore its impact on short- and long-term emotional outcome. METHODS: Data from two studies are reported. Participants were non-elective patients and > or =18 years of age with an ICU stay > or =24 hours. Study 1 (n = 34) generated and developed items. Study 2 (n = 109) allowed evaluation of the factor analytic structure and psychometrics of the questionnaire. RESULTS: From a set of 31 items, exploratory factor analysis identified four components of the intensive care experience: 'awareness of surroundings' (nine items), 'frightening experiences' (six items), 'recall of experience' (five items), and 'satisfaction with care' (four items). Cronbach's alpha statistics were acceptable for each component (0.71-0.93). Correlational analysis with the subscales of the Hospital Anxiety and Depression Scale and Impact of Event Scale demonstrated concurrent and univariate predictive validity. The intensive care experience was associated with adverse emotional outcome in both the short- and long-term. DISCUSSION: The intensive care experience questionnaire identified four dimensions of experience and performed satisfactorily in these developmental analyses. Further study of an independent intensive care unit data set is necessary to confirm these findings, including the four-component structure. Development of a standardized measure provides the opportunity to increase our understanding of the intensive care experience. The questionnaire may be useful to inform the development of effective interventions to improve subsequent outcomes for these patients.

Adaptation, Psychological↗