There were no clinical benefits to administering phenylephrine as an infusion versus a bolus regimen. The bolus regimen maintained maternal arterial blood pressure closer to baseline in the initial minutes after spinal injection but this had no clinical benefits. The infusion regimen required a higher total dose of phenylephrine to maintain maternal arterial blood pressure at baseline during the predelivery period.

No abstract

Japan has seen significant developments in obstetric anesthesia in recent years, including the establishment of the Japanese Society of Obstetric Anesthesia and Perinatology. However, labor pain, which is one of the most important issues in obstetric practice, is still not treated aggressively. The rate of epidural administration for labor analgesia is very low in Japan as compared to other developed countries. Remifentanil has been used for labor analgesia, as part of general anesthesia for cesarean delivery, as well as for various fetal procedures around the world. Intravenous patient-controlled analgesia (IVPCA) with remifentanil is considered to be a reasonable option for labor pain relief. Several studies have demonstrated its efficacy with minimal maternal and neonatal adverse effects. On the other hand, reports of cases of maternal cardiac and respiratory arrest with remifentanil IVPCA within the past couple of years have redirected our attention to its safe use. Remifentanil IVPCA warrants one-to-one nursing monitoring, appropriate education of healthcare providers, continuous maternal oxygen saturation monitoring, end-tidal CO monitoring, and availability of both maternal and neonatal resuscitation equipment. This article provides an overview of knowledge and principles of using remifentanil IVPCA for labor analgesia and introduces its potential usage in Japan.

ESR spectra of the short-lived radicals of catechol and gallic acid formed by reaction with hydroxyl radical (HO • ) in acidic solution were measured using a dielectric mixing resonator and were compared with those formed by autoxidation in an alkaline solution. The triple triplet and triplet absorptions of catechol and gallic acid in alkaline solution showed that they were the phenoxy radicals and that the residual phenolic hydroxyl groups (φ-OH) were ionized. On the contrary, the lines were broad and unresolvable in acidic solution, suggesting that the radicals were exchanging between some limiting structures with a rate that affected the line shape. The radical is thought to be phenoxy formed by dehydrogenation with HO • , and the position of the unpaired electron can move to another φ-OH through a cationic radical structure as an intermediate. Thus, a simulation was performed assuming that the Bloch equation is applicable to some groups of the lines of the limiting structures. A method for the quantum-chemical analysis was developed, and the exchange rate and the hyperfine splitting constants were obtained from the best-fit spectra using a revised Marquardt method. The results suggest that polyphenols scavenge HO • using the φ-OHs, but it was impossible to determine which φ-OH was used from the ESR spectra because the structure was changing among a few structures.

No abstract

The purpose of this prospective observational study was to measure gastric volumes in fasted patients using bedside gastric ultrasound. Patients presenting for non-emergency surgery underwent a gastric antrum assessment, using the two-diameter and free-trace methods to determine antral cross-sectional area. Gastric residual volume (GRV) was calculated using a validated formula. Univariate and multivariable analyses were performed to examine any potential relationships between 'at risk' GRVs (>100 ml) and patient factors. Two hundred and twenty-two successful scans were performed; of these 110 patients (49.5%) had an empty stomach, nine patients (4.1%) had a GRV >100 ml, and a further six patients (2.7%) had a GRV >1.5 ml/kg. There was no significant relationship between 'at risk' GRV and obesity, diabetes mellitus, gastro-oesophageal reflux disease or opioid use, although our study had insufficient power to exclude an influence of one or more of these factors. Our results indicate that despite compliance with fasting guidelines, a small percentage of patients still have GRVs that pose a pulmonary aspiration risk. Anaesthetists should consider this background incidence when choosing anaesthesia techniques for their patients. While future observational studies are required to determine the role of preoperative bedside gastric ultrasound, it is possible that this technique may assist anaesthetists in identifying patients with 'at risk' GRVs.

The white rot fungus, Ceriporiopsis subvermispora, is able to degrade lignin in wood without intensive damage to cellulose. Since lignin biodegradation by white rot fungi proceeds by radical reactions, accompanied by the production of a large amount of Fe3+-reductant phenols and reductive radical species in the presence of iron ions, molecular oxygen, and H2O2, C. subvermispora has been proposed to possess a biological system which suppresses the production of a cellulolytic active oxygen species, *OH, by the Fenton reaction. In the present paper, we demonstrate that 1-nonadecene-2,3-dicarboxylic acid (ceriporic acid B), an extracellular metabolite of C. subvermispora, strongly inhibited *OH production and the depolymerization of cellulose by the Fenton reaction in the presence of iron ions, cellulose, H2O2, and a reductant for Fe3+, hydroquinone (HQ), at the physiological pH of the fungus.

The development of a novel pretreatment system using catalysts with high safety and low cost is pivotal to establish lignocellulosic biorefinery. We evaluated 16 Lewis acid catalysts for microwave solvolysis pretreatment to enhance enzymatic saccharification of woody biomass and found that very cheap and safe food additives, alum, are effective for the pretreatment, giving high sugar yield comparable to that of AlCl 3 , a strong Lewis acid catalyst effective both for softwood and hardwood. In microwave solvolysis of Japanese cedar, Paraserianthes falcataria and Eucalyptus globulus using alum in ethylene glycol/water (9/1, w/w), the maximum sugar yields after enzymatic saccharification reached 47.8, 51.0, and 59.7% based on the weight of each wood. The same reactions in glycol/water (9/1, w/w) gave the sugar yield, 34.5, 54.1, and 58.5%, indicating differential reactivity of the Lewis acid/solvent system depending on wood species. We found that efficiency and selectivity of pretreatment with a flocculating and astringent agent, Al 2 (SO 4 ) 3 , was promoted by microwave. Reaction of Japanese beech wood with Al 2 (SO 4 ) 3 in 50% aqueous 1-propanol by microwave and conventional heating revealed that microwave irradiation suppressed excessive degradation of carbohydrates into furfural derivatives. Saccharification of the wood pretreated by microwave with 8 and 1 filter paper units of cellulolytic enzymes gave sugar yields per wood of 50.3 and 43.9%, whereas the same reaction in an autoclave resulted in 48.9 and 34.7% yields, demonstrating that microwave irradiation accelerated the saccharification and the effect was remarkable with a lower enzyme dosage.