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To assess the efficacy and safety of ultra rapid (15 minute) infusion of iron polymaltose to iron deficient patients during general anaesthesia, we performed a prospective, interventional non-randomised study on 99 adult patients with iron deficiency with or without anaemia presenting for surgery under general anaesthesia. Over 15 minutes during the maintenance phase of anaesthesia, patients were given iron polymaltose, 500 mg if not anaemic, or 1,000 mg if anaemic. Haemodynamic stability, immediate or delayed iron-related side-effects and efficacy at six weeks were assessed. The incidence of significant hypotension or the requirement for vasopressor was not different before, during or after the iron infusion. There were no serious intraoperative events (allergic reactions or skin staining). Mean (standard deviation, SD) haemoglobin rose from 121 (14) g/l preoperatively to 131 (12) g/l at six weeks (P <0.001). Mean (SD) ferritin rose from 17 (12) µg/l to 110 (83) µg/l by six weeks (P <0.001). At six weeks only four out of 64 contactable patients (6.25%) had a ferritin of <30 µg/l. The incidence of immediate or delayed side-effects was similar to patients undergoing outpatient iron polymaltose infusions and reflective of a post-surgical population. We conclude that up to 1,000 mg of iron polymaltose can be given over 15 minutes without significant haemodynamic compromise to selected patients undergoing general anaesthesia. Iron polymaltose administered in this way appears efficacious in treating iron deficiency.

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An accurate and reproducible recording of laryngoscopic view at tracheal intubation is an important aspect of anaesthetic practice. Unlike direct laryngoscopy, in which the view achieved by the line of sight directly relates to the ease of intubating the trachea, videolaryngoscopy can create a situation in which the view is good, but intubation difficult or impossible. Communicating this to a subsequent anaesthetist is important. We compared three scoring systems: Cormack and Lehane; POGO (percentage of glottic opening); and the Fremantle score, as used by 74 critical care doctors rating 30 anonymised videos of videolaryngoscopic intubations. Accuracy (degree of agreement of score with an expert panel assessment) was higher for POGO (75.5%) and the Fremantle score (73.9%) than for Cormack and Lehane (65.4%; p < 0.001). Intra-rater reliability (mean free marginal Kappa for ordinal scores and mean Cronbach's Alpha for continuous score) was higher for Fremantle score (0.796) and Cormack and Lehane (0.773) than POGO (0.693). Inter-rater reliability for Fremantle score (0.618) and POGO (0.614) were similar and higher than the inter-rater reliability of Cormack and Lehane 0.464 (p < 0.001). The higher accuracy and inter-rater reliability of POGO and the Fremantle score suggest they are preferable to Cormack and Lehane for use when documenting videolaryngoscopy. The additional information about ease of intubation conveyed by the Fremantle score may support its routine use in recording videolaryngoscopic intubation.

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A strong relationship between patient data and preoperative clinical decisions could potentially be used to support clinical decisions in preoperative management. The aim of this exploratory study was to determine the relationship between key patient data and pooled clinical opinions on management. In a previous study, panels of anaesthetists compared the quality of computer-assisted patient health assessments with outpatient consultations and made decisions on the need for preoperative tests, no preoperative outpatient assessment, possible postoperative intensive care unit/high dependency unit requirements and aspiration prophylaxis. In the current study, the relationship between patient data and these decisions was examined using binomial logistic regression analysis. Backward stepwise regression was used to identify independent predictors of each decision (at P >0.15), which were then incorporated into a predictive model. The number of factors related to each decision varied: blood picture (four factors), biochemistry (six factors), coagulation studies (three factors), electrocardiography (eight factors), chest X-ray (seven factors), preoperative outpatient assessment (17 factors), intensive care unit requirement (eight factors) and aspiration prophylaxis (one factor). The factor types also varied, but included surgical complexity, age, gender, number of medications or comorbidities, body mass index, hypertension, central nervous system condition, heart disease, sleep apnoea, smoking, persistent pain and stroke. Models based on these relationships usually demonstrated good sensitivity and specificity, with receiver operating characteristics in the following areas under curve: blood picture (0.75), biochemistry (0.86), coagulation studies (0.71), electrocardiography (0.90), chest X-ray (0.85), outpatient assessment (0.85), postoperative intensive care unit requirement (0.88) and aspiration prophylaxis (0.85). These initial results suggest modelling of patient data may have utility supporting clinicians' preoperative decisions.

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Clear documentation of anaesthetic technique, difficulties and complications is an essential part of good anaesthetic practice, particularly in the area of airway management. The current convention of describing intubation using a videolaryngoscope only in terms of a Cormack and Lehane score is at best unhelpful and at worst dangerous. In an attempt to address the inadequacy of a Cormack and Lehane score to describe videoscopic intubation, we propose a three part scoring system: view, ease and device - the 'Fremantle Score'. Preliminary evaluation of this system in a diverse group of anaesthetists utilising four available videolaryngoscopes in a simulated normal and difficult airway manikin has demonstrated that the system is easy to use, easy to understand and relevant. In three of the eight device and manikin combinations studied, the videolaryngoscopic view correlated with the ease of intubation. This highlights the need for an alternative tool to describe intubation with a videolaryngoscope. We consider this development of a specific videoscopic scoring system a first step in better describing intubation by a videolaryngoscope and improving patient care.

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In order to assess the potential utility of guided patient self-assessment as an early preoperative triage tool, a computer-assisted questionnaire delivered by a non-clinician via telephone was 1) compared to face-to-face interview and examination by anaesthetists in outpatient clinics and 2) evaluated as a mechanism to stream patients to day of surgery assessment. In total, 514 patients scheduled for elective surgery in two tertiary public hospitals were assessed initially by telephone and then in an outpatient clinic. Both forms of assessment were marked by panels of specialist anaesthetists, who also provided an opinion on which patients would have been suitable to bypass preoperative anaesthetic outpatient assessment based upon information provided by the telephone interview. Overall, the quality of assessment provided by non-clinician telephone interview was comparable to face-to-face interview by anaesthetists, although more complex issues required face-to-face assessment. Panel review considered that 398 patients (60%) would not have required evaluation by an anaesthetist until the day of surgery, thus avoiding the need to separately attend a preoperative outpatient clinic. The sensitivity of telephone interview provided information to correctly classify patients as suitable for day of surgery evaluation was 98% (95% confidence interval 96 to 99%) with a specificity of 97% (95% confidence interval 92 to 98%). This study demonstrates that remote computer-assisted assessment can produce quality patient health information and enable early patient work-up and triage with the potential to reduce costs through more efficient use of resources.

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The kinetics of trichloroethene (TCE) reductive dechlorination mediated by humic-Ni complexes in homogeneous aqueous solution using titanium(III) citrate as the bulk reductant was examined under various environmental conditions (e.g., pH and ionic compositions). Using Ca2+, Zn2+, and Hg2+ ions to vary Aldrich humic acid (HA)-Ni complex concentrations, pseudo-first-order rate constants for TCE reduction were observed to be proportional to HA-Ni levels (as calculated by speciation modeling), confirming HA-Ni complexes as the probable active mediator species. TCE reduction by HA-Ni was observed to be strongly pH dependent and could be due to both the variations of HA-Ni concentration and Eh with pH. Evidence is presented which suggests that quinone moieties may not be crucial for the humic-Ni mediated reduction of TCE. A variety of natural soil and aqueous humic material and Ni systems were examined, and some showed reactivity toward TCE. Humic-metal complexes may be important electron-transfer mediators in natural systems.

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A bacterium capable of degrading 2-methylpyridine was isolated by enrichment techniques from subsurface sediments collected from an aquifer located at an industrial site that had been contaminated with pyridine and pyridine derivatives. The isolate, identified as an Arthrobacter sp., was capable of utilizing 2-methylpyridine, 2-ethylpyridine, and 2-hydroxypyridine as primary C, N, and energy sources. The isolate was also able to utilize 2-, 3-, and 4-hydroxybenzoate, gentisic acid, protocatechuic acid and catechol, suggesting that it possesses a number of enzymatic pathways for the degradation of aromatic compounds. Degradation of 2-methylpyridine, 2-ethylpyridine, and 2-hydroxypyridine was accompanied by growth of the isolate and release of ammonium into the medium. Degradation of 2-methylpyridine was accompanied by overproduction of riboflavin. A soluble blue pigment was produced by the isolate during the degradation of 2-hydroxypyridine, and may be related to the diazadiphenoquinones reportedly produced by other Arthrobacter spp. when grown on 2-hydroxypyridine. When provided with 2-methylpyridine, 2-ethylpyridine, and 2-hydroxypyridine simultaneously, 2-hydroxypyridine was rapidly and preferentially degraded; however there was no apparent biodegradation of either 2-methylpyridine or 2-ethylpyridine until after a seven day lag. The data suggest that there are differences between the pathway for 2-hydroxypyridine degradation and the pathways(s) for 2-methylpyridine and 2-ethylpyridine.

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Micrococcus luteus produced 29 muM riboflavin during growth on 6.5 mM pyridine but not during growth on other substrates. On the basis of the results of radiolabelling studies, riboflavin was not directly synthesized from pyridine. Pyridine may interfere with riboflavin biosynthesis or elicit a general stress response in M. luteus.