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The aim of this chapter is to focus on evidence-based health economics in anaesthesia. More and more, requests for additional facilities will have to be based on detailed arguments supported by ‘hard evidence’ as to the gain to be expected from the patient's angle and the cost. Evidence-based clinical practice in anaesthesia isolated from economic issues is not an optimal goal. As clinicians we have to demonstrate not only the need for the use of evidence-based principles in economic evaluation, but also that such principles should themselves be based on health economics. This chapter shows how to bring economic evaluation and systematic review together, and how to use such evaluations in the clinical setting. It shows how economics can be used to broaden the evidence base for a more efficient and equitable health policy, and sets a future research agenda for this challenging area of work in Cochrane reviews dealing with anaesthesia topics.

Smoking is a risk factor for postoperative complications such as pneumonia, infections and impaired wound healing. These can be reduced by preoperative stop-smoking intervention six to eight weeks before surgery. The aim of this study was to evaluate the costs and benefits of a stop-smoking intervention program by means of cost consequence analysis (CCA). A total of 120 smokers scheduled for hip or knee alloplasty were randomised to either a control group or an intervention group. The intervention group received an intensive stop-smoking intervention six to eight weeks before surgery. The focus of the economic analysis was on direct costs. Diagnosis-related group (DRG) costs were used for estimating the costs of secondary surgery. In all, 64% of the patients in the intervention group stopped smoking before surgery, as opposed to 8% in the control group. In the intervention group, 5.4% of the patients had wound complications, and 3.6% needed secondary surgery. In the control group, 30.8% had wound complications and 15.4% needed secondary surgery. The direct costs were almost the same in the two groups, whereas the overall costs in the intervention group were lower than in the control group. The economic analysis shows that a preoperative smoking intervention program is beneficial to society and the patient alike. Based on these calculations, we recommend that all patients scheduled for hip or knee alloplasty be given preoperative stop-smoking intervention.

The aim of this chapter is to clarify the effect of perioperative monitoring with pulse oximetry and to identify the adverse outcomes that might be prevented or improved by its use. Trials were identified by computerized searches of The Cochrane Library, MEDLINE and EMBASE, and by checking the reference lists of trials and review articles. All controlled trials that randomized patients to either pulse oximetry or no pulse oximetry during the perioperative period, including the operating and recovery room, were included in the search. Pulse oximetry monitoring was shown to substantially reduce the extent of perioperative hypoxaemia, enabling the detection and treatment of hypoxaemia and related respiratory events, and promoting several changes in patient care. The implementation of perioperative pulse oximetry monitoring does not significantly reduce the number of postoperative complications, but the question remains whether pulse oximetry can improve outcomes in other situations. Pulse oximetry has been adopted all over the world in clinical practice as a tool that guides anaesthesiologists in the daily management of patients: in teaching situations, in emergencies, and especially in the care of children. Given the relatively small number of patients studied in these trials and the rare events being sought, the studies of perioperative monitoring with pulse oximetry were not able to show an improvement in the outcomes studied.

Monitoring with pulse oximetry might improve patient outcome by enabling an early diagnosis and consequently, correction of perioperative events that might cause postoperative complications or even death. Only a few randomised clinical trials of pulse oximetry have been performed during anaesthesia and in the recovery room which describe perioperative hypoxaemic events, postoperative cardiopulmonary complications and cognitive dysfunction.To study the effect of perioperative monitoring with pulse oximetry to clearly identify the adverse outcomes that might be prevented or improved by the use of pulse oximetry.Trials were identified by computerised searches of the Cochrane Library, MEDLINE, EMBASE, and by checking the reference lists of trials and review articles.All controlled trials that randomised patients to either pulse oximetry or no pulse oximetry during the perioperative period, including the operating and recovery room.We collected data in relation to events detectable by pulse oximetry, any serious complications that occurred during anaesthesia or in the postoperative period, intra- or postoperative mortality, and duration of recovery or intensive care stay. Formal statistical synthesis of individual trials was not performed in view of the variety of outcomes studied.Searching identified six reports; four studies with data from a total of 21,773 patients were considered eligible for analysis. Only two studies specifically addressed the outcomes in question; both found no effect on the rate of postoperative complications using perioperative pulse oximetry. Two studies used hypoxaemia detectable by pulse oximetry to assess the value of perioperative monitoring, although outcomes were not given. It was found that hypoxaemia was reduced in the pulse oximetry group both in the operating theratre and in the recovery room. During observation in the recovery room, the incidence of hypoxaemia in the pulse oximetry group was 1.5-3 times less. The postoperative cognitive function using the Wechsler memory scale and continuous reaction time was independent of perioperative monitoring with pulse oximetry. The other study showed that postoperative complications occurred in 10% of the patients in the oximetry group and in 9.4% in the control group. The two groups did not differ in cardiovascular, respiratory, neurologic, or infectious complications. The duration of hospital stay was a median of 5 days in both groups, and an equal number of in-hospital deaths was registered in the two groups.The studies confirmed that pulse oximetry can detect hypoxaemia and related events. However, we have found no evidence that pulse oximetry affects the outcome of anaesthesia. The conflicting subjective and objective results of the studies, despite an intense, methodical collection of data from a relatively large population, indicate that the value of perioperative monitoring with pulse oximetry is questionable in relation to improved reliable outcomes, effectiveness and efficiency.

Sedimentary basins are large depressions in the earth’s crust containing from a few to more than 15 km of sediments. At deposition, sediments may contain in excess of 50% water; huge volumes of fluids are thus buried in deep basins. Fluid is also produced by water-releasing reactions in the sediments and positive topography surrounding the basin may drive groundwater into it under the influence of gravity. Fluids in basins will move relative to the sediment grains, transporting heat and solids in solution; they can thus influence sediment temperatures and cause diagenetic reactions. The extent to which this occurs will depend on the velocity of the fluid, its temperature and the solutes dissolved in it. In basins a myriad of factors will control fluid flow and fluid-rock interaction, consequently only rather rough estimates of fluid movements and their effects are in general achievable.

Background: Serum markers of inflammation are candidate biomarkers in multiple sclerosis (MS). ω-3 fatty acids are suggested to have anti-inflammatory properties that might be beneficial in MS. We aimed to explore the relationship between serum levels of inflammation markers and MRI activity in patients with relapsing remitting MS, as well as the effect of ω-3 fatty acids on these markers. Methods: We performed a prospective cohort study in 85 relapsing remitting MS patients who participated in a randomized clinical trial of ω-3 fatty acids versus placebo (the OFAMS study). During a period of 24 months 12 repeated magnetic resonance imaging (MRI) scans and nine serum samples were obtained. We measured 10 inflammation markers, including general down-stream markers of inflammation, specific markers of up-stream inflammatory pathways, endothelial action, and matrix regulation. Results: After Bonferroni correction, increasing serum levels of CXCL16 and osteoprotegerin were associated with low odds ratio for simultaneous MRI activity, whereas a positive association was observed for matrix metalloproteinase (MMP) 9. CXCL16 were also associated with low MRI activity the next month, but this was not significant after Bonferroni correction. In agreement with previously reported MRI and clinical results, ω-3 fatty acid treatment did not induce any change in the inflammation markers. Conclusions: Serum levels of CXCL16, MMP-9, and osteoprotegerin reflect disease activity in MS, but are not affected by ω-3 fatty acid treatment. CXCL16 could be a novel biomarker and potential predictor of disease activity in MS. © 2013 Holmøy et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The authors conducted a randomized controlled clinical trial to evaluate the usefulness of perioperative manual evaluation of the response to train-of-four (TOF) nerve stimulation. A total of 80 patients were divided into four groups of 20 each. For two groups (one given vecuronium and one pancuronium), the anesthetists assessed the degree of neuromuscular blockade during operation and during recovery from neuromuscular blockade by manual evaluation of the response to TOF nerve stimulation. In the other two groups, one of which received vecuronium and the other pancuronium, the anesthetists evaluated the degree of neuromuscular blockade solely by clinical criteria. The use of a nerve stimulator was found to have no effect on the dose of relaxant given during anesthesia, on the need for supplementary doses of anticholinesterase in the recovery room, on the time from end of surgery to end of anesthesia, or on the incidence of postoperative residual neuromuscular blockade evaluated clinically. The median (and range of) TOF ratios recorded in the recovery room were 0.75 (0.33-0.96) and 0.79 (0.10-0.97) in the vecuronium groups monitored with and without a nerve stimulator, respectively. These ratios were significantly higher than those found in the pancuronium groups, which wre 0.66 (0.06-0.90) and 0.63 (0.29-0.95), respectively. However, no difference was found between the vecuronium and pancuronium groups in the number of patients showing clinical signs of residual neuromuscular blockade, as evaluated by the 5-s head-lift test.(ABSTRACT TRUNCATED AT 250 WORDS)

Summarization: The potential leaching and availability of nitrogen in biosolids and biosolid-amended glaciated soil were investigated using mineralization and column studies. Aerobic and anaerobic mineralization studies were conducted to assess nitrogen mineralization potential from biosolid-amended glaciated soils and estimate long- and short-term mineralization rates of products. Semicontinuous column studies were conducted to assess the leachability of nitrogen from biosolid-amended soil under simulated unsaturated soil conditions. This study used a Paxton soil because its characteristics are typical of glaciated soil found in New England. Three types of biosolids, which are representative of biosolids currently available in Connecticut, were evaluated: composted biosolids (compost), cement kiln dust stabilized (CKD) biosolids, and heat-dried biosolids (pellet). Results indicate that the pellet product had the greatest mineralization potential (based on unmixed biosolids) at 5 317 mg N/kg, followed by compost (324 mg N/kg) and CKD biosolids (58 mg N/kg). Nitrogen mineralized for the anaerobic test (mixed with soil) varied from 56 to 90% of the total nitrogen and for the aerobic test varied from 19 to 57%. The CKD biosolids percolate consisted primarily of nitrate and nitrite, whereas the predominant nitrogen species found in compost and pellet biosolids percolate was ammonium. Results suggest that one-time application of biosolids at agronomic or liming rates (whichever is limiting) will cause minimal effects to groundwater. Presented on: Water environment research

The water content of olivine crystals from picrites and basalts from the North Atlantic Volcanic Province has been estimated using non-polarised Fourier transform infrared spectra. H2O concentrations vary from about 18 ppm by weight to below the detection limit of ca. 0.5 ppm. The most H2O-poor olivines (≤0.5 ppm H2O) probably reflect olivine crystallisation or re-equilibration at shallow crustal levels, possibly after magma degassing. However, some of the Mg-rich olivines (Fo87–91.5) have elevated H2O contents (3–7 ppm) and indicate the presence of mantle source regions with >300 ppm H2O for any reasonable crystallisation depth. The elevated H2O content may be sufficiently high to significantly affect the mantle viscosity and melting behaviour and thus contribute to the simultaneous production of melt over a vast area from Baffin Island to the British Isles at 58–62 Ma.

Background Perioperative hemorrhage may depend on coagulation competence and this study evaluated the influence of coagulation competence on blood loss during cystectomy due to bladder cancer. Methods Forty patients undergoing radical cystectomy were included in a randomized controlled trial to receive either lactated Ringer’s solution or Dextran 70 (Macrodex ®) that affects coagulation competence. Results By thrombelastography evaluated coagulation competence, Dextran 70 reduced “maximal amplitude” (MA) by 25 % versus a 1 % reduction with the administration of lactated Ringer’s solution (P 1500 ml) compared to only four patients (22 %) in the lactated Ringer’s group (P = 0.04). Conclusions With the use of Dextran 70 vs. lactated Ringer’s solution during cystectomy, a relation between hemorrhage and coagulation competence is demonstrated. Significant bleeding develops based on an about 25 % reduction in thrombelastography determined maximal amplitude. A multivariable model including maximal amplitude discriminates patients with severe perioperative bleeding during cystectomy. Trial registration The study was accepted on January 7th, 2013 at www.clinicaltrialsregister.eu EudraCT 2012-005040-20.

SUMMARY Crustal anatexis in volcanic rifts is discussed in terms of a 1-D numerical model incorporating lithospheric extension, emplacement of hot mafic magma at crustal levels, various crustal compositions and pre-rift conditions. Only the volume of melt generated by anatexis is considered; crustal melt segregation, transport and emplacement at higher levels are not included. We find that under a broad range of conditions, influx of mafic magma to the crust is required for substantial anatexis to take place, and once this stops, silicic magmatism dies out rapidly. In many rifts the observed change in type of magmatism from predominantly mafic to silicic during rifting is probably more due to a diminishing potential for mafic magmas to ascend though the crust than to an actual halt in mafic melt generation at depth. This has important implications where melt production rates are used to analyse the formation of volcanic rifts and margins. When influx of mafic magmas takes place over a finite period of time, they may be focused in the depth region where the potential for anatexis is largest, and in some cases more anatexis can occur than by instantaneous emplacement of the entire mafic body. Our results support the idea that the 1.6 Gyr old rapakivi granites in southern Finland were formed by anatexis of an intermediate to felsic Svecofennian crust. Provided a mantle thermal anomaly of +200‐250°C existed beneath Finland, the seismically observed ~10 km thick magmatic underplated body could have produced the exposed silicic rocks which are on average 2‐3 km thick. In the Oslo Graben in southeast Norway, where the thickness of magmatic underplating is also about 10 km, the amount of rock produced by anatexis is poorly constrained, but appears to be between 1 and 2 km. Provided the pre-rift crustal thickness in the graben was 35‐40 km or more, and heat was transported to crustal levels more eYciently than is feasible by conventional stretching models, the model predicts melt volumes in agreement with these estimates. We propose that secondary convection within the narrow graben could have contributed to the high heat transport eYciency. Finally, a conspicuous feature of the southern Finland magmatic region as well as the Oslo Graben is the large discrepancy between stretching factors derived from analysing dyke intrusions and faulting (Finland: b~1.001; Oslo Graben: b

Simple diffusion models are developed to describe vertical diffusion in Powell Lake, a meromictic former fjord containing trapped seawater. Measurements of the vertical distribution of chlorinity are used to determine the dependence of vertical diffusivity on depth. Near the bottom of the lake the vertical diffusivity is about 4 times that of the molecular diffusivity of salt. On this basis, ions with different molecular diffusion coefficients will be lost from the bottom of the lake at different rates, which partially explains differences observed in the ratios of concentrations of ions in saline bottom water from ratios characteristic of seawater. The observed increase in temperature with depth is shown to result from the geothermal heat flux through the lake's bottom.