Effects of directional adaptation on selenium tolerance and accumulation of heterotrophic Chlorella pyrenoidosa / 生物工程学报

Selenium (Se) is an essential trace element for organisms. Se deficiency will cause diseases such as Keshan disease and Kashin-Beck in human being, and huge loss to animal husbandry. Currently available Se supplements have such problems as low Se content, poor bioavailability, and poor safety. Chlorella pyrenoidosa can produce bioavailable and safe organic Se under suitable conditions, which is thus a promising Se supplement. Therefore, in this study, we tried to improve the Se tolerance and accumulation of C. pyrenoidosa by directional adaptation. To be specific, we gradually increased the concentration of Na2SeO3 in medium to domesticate C. pyrenoidosa and optimized the adapting time and concentration gradient of Na2SeO3 during the adaptation. The results showed that the adapted C. pyrenoidosa was more tolerant to Se and had stronger Se enrichment ability. In 5 L fermenter, the adapted strains could tolerate 40 mg/L Na2SeO3 and the synthesis rate of organic Se was 175.6% higher. Then, Se addition method in the 5 L fermenter was optimized. The result demonstrated that addition of Na2SeO3 at 40 mg/L during heterotrophic culture achieved the final dry weight of C. pyrenoidosa cells at 106.4 g/L, content of organic Se at 1 227 mg/kg, and synthesis rate of organic Se at 1.36 mg/(L·h). Compared with the reported highest cell density of 75 g/L and the highest organic Se content of 560 mg/kg, the corresponding figures in this study were 41.9% and 119.1% higher, respectively. In conclusion, directional adaptation can remarkably improve the Se tolerance and enrichment of C. pyrenoidosa.

Mechanism of trehalose-enhanced metabolism of heterotrophic nitrification-aerobic denitrification community under high-salt stress / 生物工程学报

Heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria are aerobic microorganisms that can remove nitrogen under high-salt conditions, but their performance in practical applications are not satisfactory. As a compatible solute, trehalose helps microorganisms to cope with high salt stress by participating in the regulation of cellular osmotic pressure, and plays an important role in promoting the nitrogen removal efficiency of microbial populations in the high-salt environment. We investigated the mechanism of exogenous-trehalose-enhanced metabolism of HN-AD community under high-salt stress by starting up a membrane aerobic biofilm reactor (MABR) to enrich HN-AD bacteria, and designed a C150 experimental group with 150 μmol/L trehalose addition and a C0 control group without trehalose. The reactor performance and the community structure showed that NH4+-N, total nitrogen (TN) and chemical oxygen demand (COD) removal efficiency were increased by 29.7%, 28.0% and 29.1%, respectively. The total relative abundance of salt-tolerant HN-AD bacteria (with Acinetobacter and Pseudofulvimonas as the dominant genus) in the C150 group reached 66.8%, an 18.2% increase compared with that of the C0 group. This demonstrated that trehalose addition promoted the enrichment of salt-tolerant HN-AD bacteria in the high-salt environment to enhance the nitrogen removal performance of the system. In-depth metabolomics analysis showed that the exogenous trehalose was utilized by microorganisms to improve proline synthesis to increase resistance to high-salt stress. By regulating the activity of cell proliferation signaling pathways (cGMP-PKG, PI3K-Akt), phospholipid metabolism pathway and aminoacyl-tRNA synthesis pathway, the abundances of phosphoethanolamine, which was one of the glycerophospholipid metabolites, and purine and pyrimidine were up-regulated to stimulate bacterial aggregation and cell proliferation to promote the growth of HN-AD bacteria in the high-salt environment. Meanwhile, the addition of trehalose accelerated the tricarboxylic acid (TCA) cycle, which might provide more electron donors and energy to the carbon and nitrogen metabolisms of HN-AD bacteria and promote the nitrogen removal performance of the system. These results may facilitate using HN-AD bacteria in the treatment of high-salt and high-nitrogen wastewater.

Advances in synthetic biology of CO2 fixation by heterotrophic microorganisms / 生物工程学报

Human activities increase the concentration of atmospheric carbon dioxide (CO2), which leads to global climate warming. Microbial CO2 fixation is a promising green approach for carbon neutral. In contrast to autotrophic microorganisms, heterotrophic microorganisms are characterized by fast growth and ease of genetic modification, but the efficiency of CO2 fixation is still limited. In the past decade, synthetic biology-based enhancement of heterotrophic CO2 fixation has drawn wide attention, including the optimization of energy supply, modification of carboxylation pathway, and heterotrophic microorganisms-based indirect CO2 fixation. This review focuses on the research progress in CO2 fixation by heterotrophic microorganisms, which is expected to serve as a reference for peaking CO2 emission and achieving carbon neutral by microbial CO2 fixation.

Enhancement of harvesting efficiency and polyunsaturated fatty acid-rich lipid production of Aurantiochytrium sp. SW1 by co-cultivation with oleaginous fungus Cunninghamella bainieri 2A1

Aims@#Thraustochytrids have been shown to be excellent lipid producers due to their ability to accumulate over 50% lipid (g/g biomass) containing up to 50% docosahexaenoic acid (DHA). However, efficient and cost-effective cell recovery of lipid-rich biomass has become a significant challenge at the industrial scale. In this study, we attempted to enhance the harvesting efficiency (HE) and the DHA content of Aurantiochytrium sp. through co-cultivation with a γ-linolenic acid (GLA)-producing oleaginous filamentous fungus, Cunninghamella bainieri 2A1.@*Methodology and results@#A 72 h old C. bainieri 2A1 culture in the form of loose mycelia or pellets of various sizes was added into 72 h old Aurantiochytrium sp. cultures and further incubated for 48 h. The HE of Aurantiochytrium sp. was then determined by comparing the remaining OD values of the supernatant with and without minimal centrifugation at 4000× g. Results showed that 63.23% of HE was achieved without centrifugation from co-cultivation with dispersed mycelia. Higher HE between 96.71-99.55% was achieved when centrifugation was implemented, with the highest value resulting from co-cultivation with dispersed mycelia. These are higher than HE of centrifuged control cultures (80%) consisting of Aurantiochytrium sp. monocultures, suggesting that co-cultivation with C. bainieri 2A1 facilitates the recovery of Aurantiochytrium sp. cells. Moreover, the co-cultivation also resulted in a 28% increase in DHA compared to non-optimized cultures.@*Conclusion, significance and impact of study@#This study provides the first evidence of enhancement in harvesting and DHA content of oleaginous thraustochytrids that could be achieved through co-cultivation with oleaginous fungi.

Recent progress in photosynthetic microbial co-culture systems / 生物工程学报

Co-culture systems consisted of photosynthetic microorganisms and others heterotrophic microbes have attracted great attention in recent years. These systems show many advantages when compared with single culture grown under autotrophic conditions, such as less vulnerable to pollution and more stability, thus have been applied to wastewater treatment, soil remediation, biodegradable harmful substances, and production of high value-added products. In order to explore basic theory and further applications, we summarize here recent progresses in artificial co-culture systems of using photosynthetic microorganisms, to provide a current scientific understanding for the rational design of the co-culture system based on photosynthetic microorganisms using synthetic biology.

Advances in heterotrophic nitrification-aerobic denitrifying bacteria for nitrogen removal under extreme conditions / 生物工程学报

Heterotrophic nitrification-aerobic denitrification (HN-AD) is an enrichment and breakthrough theory of traditional autotrophic nitrification heterotrophic denitrification. Heterotrophic nitrification-aerobic denitrifiers with the feature of wide distribution, strong adaptability and unique metabolic mechanism have many special advantages, including fast-growing, rapid biodegradability and long lasting activity, which can rapidly remove ammonia nitrogen, nitrate nitrogen (NO₃⁻-N) and nitrite nitrogen (NO₂⁻-N) under aerobic conditions simultaneously. Therefore, HN-AD bacteria show the important potential for denitrification under extreme conditions with high-salt, low-temperature or high-ammonia nitrogen environment, and HN-AD bacteria attract extensive attention in the field of biological denitrification of wastewater. In this review, we first introduce the previously reported HN-AD bacterial species which have denitrification performance in the extreme environments and state their typical metabolic mechanism. Then, we systematically analyze the nitrogen removal characteristics and potential under extreme conditions. We also briefly describe the progress in the application of HN-AD bacterial. Finally, we outlook the application prospects and research directions of HN-AD denitrification technology.

Advances in metabolic engineering of heterotrophic microorganisms for CO₂ fixation: a review / 生物工程学报

Environmental protection and energy supply are our two major concerns. Greenhouse gases released from energy consumption have serious impact on the environment. CO₂ fixation can be used to convert CO₂ into fuels or chemicals. However, natural carbon-fixing organisms usually have some disadvantages such as slow growth and low carbon fixation efficiency. Enhancing or remodeling CO₂ fixation pathways in model microorganisms can realize CO₂ recycling, which can further increase fuel or chemical production and reduce greenhouse gas emission. This review describes in detail metabolic engineering of CO₂ fixation pathways to improve chemical production and sugar synthesis, elaborates the role of relevant metabolic pathways and key enzymes in CO₂ fixation, introduces the application of electro-biochemical synthesis system, shows the great potential of CO₂ fixation, and prospects the future research direction of CO₂ fixation.

Diversity of retrievable heterotrophic bacteria in Kongsfjorden, an Arctic fjord

Abstract The diversity and abundance of retrievable pelagic heterotrophic bacteria in Kongsfjorden, an Arctic fjord, was studied during the summer of 2011 (June, August, and September). Retrievable bacterial load ranged from 103 to 107 CFU L−1 in June, while it was 104-106 CFU L−1 in August and September. Based on 16S rRNA gene sequence similarities, a higher number of phylotypes was observed during August (22 phylotypes) compared to that during June (6 phylotypes) and September (12 phylotypes). The groups were classified into four phyla: Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes. Bacteroidetes was represented only by a single member Leewenhoekiella aequorea during the three months and was dominant (40%) in June. However, this dominance changed in August to a well-known phytopathogenic species Rhodococcus fascians (32%), which could be a result of decrease in the phytoplankton biomass following the secondary bloom. It is the first report of Halomonas titanicae isolation from the Arctic waters. It showed an increase in its abundance with the intrusion of Atlantic water into Kongsfjorden. Increased abundance of Psychrobacter species in the late summer months coincided with the presence of cooler waters. Thus, the composition and function of heterotrophic bacterial community was fundamentally different in different months. This could be linked to the changes in the water masses and/or phytoplankton bloom dynamics occurring in Arctic summer.

Low field nuclear magnetic resonance for rapid quantitation of microalgae lipid and its application in high throughput screening / 生物工程学报

A rapid and accurate determination method of lipids in microalgae plays a significant role in an efficient breeding process for high-lipid production of microalgae. Using low field nuclear magnetic resonance (LF-NMR), we developed a direct quantitative method for cellular lipids in Chlorella protothecoides cells. The LF-NMR signal had a linear relationship with the lipid content in the microalgae cells for both dry cell samples and algal broth samples (R2 > 0.99). These results indicated that we could use this method for accurate determination of microalgal lipids. Although LF-NMR is a rapid and easy lipid determination method in comparison to conventional methods, low efficiency would limit its application in high throughput screening. Therefore, we developed a novel combined high throughput screening method for high-lipid content mutants of C. protothecoides. Namely, we initially applied Nile red staining method for semi-quantification of lipid in the pre-screening process, and following with LF-NMR method for accurate lipid determination in re-screening process. Finally, we adopted this novel screening method in the breeding process of high-lipid content heterotrophic cells of C. protothecoides. From 3 098 mutated strains 108 high-lipid content strains were selected through pre-screening process, and then 9 mutants with high-lipid production were obtained in the re-screening process. In a consequence, with heterotrophical cultivation of 168 h, the lipid concentration could reach 5 g/L, and the highest lipid content exceeded 20% (W/W), which was almost two-fold to that of the wild strain. All these results demonstrated that the novel breeding process was reliable and feasible for improving the screening efficiency.

Optimization of photoautotrophic lipid production of Chlorella ellipsoidea seeded with heterotrophic cells / 生物工程学报

Photoautotrophic cultivation with heterotrophic cells as seeds (heterotrophic cells/photoautotrophic cultivation) is an effective way for the development of microalgal biofuel, but its development potential from the point of process optimization has not been investigated in literatures. To evaluate this, the optimizations of medium and culture conditions for Chlorella ellipsoidea were studied. In the heterotrophic stage, the biomass concentration reached 11.04 g/L with the optimized medium in flask, which were 28.0% higher than that with the original medium, and the biomass concentration reached 73.89 g/L in 5-L fermenter. In the photoautotrophic stage, the culture medium and conditions were studied in a 2-L column photobioreactor. The maximum biomass concentration, lipid content and lipid productivity reached 1.62 g/L, 36.34% and 6.1 mg/(L·h) under the optimal photoautotrophic conditions. The lipids were mainly composed of C16-C18 fatty acids, which were raw material suitable for biodiesel. After optimization, heterotrophic cells/photoautotrophic cultivation can significantly improve the capacity of biofuel production by Chlorella ellipsoidea, this method is also expected to be an efficient way for the cultivation of other microalgae that can grow heterotrophically.

Yearly variation of bacterial production in the Arraial do Cabo protection area (Cabo Frio upwelling region): an evidence of anthropogenic pressure

Arraial do Cabo is where upwelling occurs more intensively on the Brazilian coast. Although it is a protection area it suffers anthropogenic pressure such as harbor activities and sporadic sewage emissions. Short-time studies showed a high variability of bacterial production (BP) in this region but none of them evaluated BP during long periods in a large spatial scale including stations under different natural (upwelling and cold fronts) and anthropogenic pressures. During 2006, we sampled surface waters 10 times (5 in upwelling and 5 in subsidence periods) in 8 stations and we measured BP, temperature as well as the concentrations of inorganic nutrients, pigments and particulate organic matter (POM). BP was up to 400 times higher when sewage emissions were observed visually and it had a positive correlation with ammonia concentrations. Therefore, in 2007, we did two samples (each during upwelling and subsidence periods) during sewage emissions in five stations under different anthropogenic pressure and we also measured particles abundance by flow cytometry. The 12 samples in the most impacted area confirmed that BP was highest when ammonia was higher than 2 μM, also reporting the highest concentrations of chlorophyll a and suspended particles. However, considering all measured variables, upwelling was the main disturbing factor but the pressure of fronts should not be neglected since it had consequences in the auto-heterotrophic coupling, increasing the concentrations of non fluorescent particles and POM. Stations clustered in function of natural and anthropogenic pressures degrees and both determined the temporal-spatial variability.

Flagellate protist abundance in phytotelmata of Aechmea distichantha Lem. (Bromeliaceae) in the upper Paraná river basin / Abundância de protozoários flagelados em fitotelmata de Aechmea distichantha Lem. (Bromeliaceae) na bacia do alto rio Paraná

In some Bromeliaceae species the leaf sheaths form a tank or phytotelma, accumulating water and organic detritus, conditions that allow the establishment of different communities. Thus, this study evaluated the relationship between diameter and volume of water in the tank of the bromeliad Aechmea distichantha Lem. and density of flagellates found in the phytotelmata, as well as the influence of the hydrological periods and proximity of sampled strata on the phytotelma patterns of abundance distribution. Samplings were conducted in two hydrological periods in 2010. In each sampling, four plants were collected from three different strata, classified according to the distance from the river level. A one-way ANOVA identified significant differences in flagellate density between hydrological periods. The influence of the water volume in the phytotelmata on the flagellate density was evidenced by regression analyses, as well as the lack of relationship between the density and perimeter of the tank. Moreover, the distance of the strata from the river level did not influence the pattern of flagellate abundance. Thus, our results suggested that the hydrological period and the volume of water in the tanks of Aechmea distichantha are determinant on the abundance of heterotrophic flagellate in the phytotelmata.

Em algumas Bromeliaceae as bainhas foliares formam uma cisterna ou fitotelma, onde ocorre acúmulo de água e detritos orgânicos, que permitem o estabelecimento de diferentes comunidades. Assim, este estudo avaliou a relação entre o diâmetro e volume de água no tanque de Aechmea distichantha Lem. e a abundância de flagelados encontrados nestes fitotelmata, bem como a influência do período hidrológico e a proximidade dos estratos amostrados sobre os padrões de distribuição desse atributo. As coletas foram realizadas em dois períodos hidrológicos no ano de 2010. Foram coletadas quatro plantas em três estratos diferentes de acordo com a distância em relação ao rio. Foram identificadas diferenças significativas entre a densidade dos flagelados e os períodos hidrológicos. Além disso, verificou-se a influência do volume de água presente nos fitotelmata sobre a densidade dos flagelados, bem como a ausência de relação entre a densidade desses protistas e o perímetro do tanque das bromélias. A distância dos distintos estratos em relação ao rio não influenciou a abundância dos flagelados. Assim, os resultados sugerem que o período hidrológico bem como o volume de água presente nos tanques de Aechmea distichantha atuam como um fator determinante sobre a abundância da comunidade de flagelados heterotróficos nos fitotelmata.

Growth of aphanothece microscopica nägeli on exogenous sugars / Cultivo da aphanothece microscopica nägeli a partir de açúcares

Biological processes for wastewater treatment generally produce biomass or active sludge without reuse. In this context, incorporation of organic matter and nutrients from agro industrial effluents into cell mass for single-cell protein allowed application of sustainable process. Cyanobacteria could be used due to its versatile metabolism. So, the aim of this paper was evaluate the growth of cyanobacteria Aphanothece microscopica Nägeli growth on heterotrophic medium with glucose, lactose and sucrose. Growth curves indicated that cultivation of cyanobacterial on the dark depend the type of carbon source and there are different mechanisms for glucose, fructose and sucrose consumption. Results suggest a useful application of cyanobacteria on organic matter removal from wastewater.

Os processos biológicos de tratamento de águas residuárias produzem grandes quantidades de biomassa geralmente sem utilização posterior. Neste contexto, a incorporação de matéria orgânica e nutrientes de efluentes agroindustriais em células microbianas visando a produção de proteínas unicelulares corresponderia a um processo sustentável. Nesse sentido, as cianobactérias poderiam ser aplicadas devido ao seu metabolismo versátil. Sendo assim, o trabalho teve como objetivo avaliar o cultivo heterotrófico da cianobactéria Aphanothece microscopica Nägeli em meios contendo glicose, lactose e sacarose. As curvas de crescimento indicaram que o cultivo heterotrófico depende do tipo de fonte de carbono, sugerindo diferentes mecanismos de incorporação e consumo da glicose, lactose sacarose. Os resultados indicam uma possível aplicação desta cianobactéria na remoção destas moléculas orgânicas em águas residuárias.

Q10 of heterotrophic activity during aerobic decomposition of Utricularia breviscapa and its effect on carbon cycling in a tropical lagoon / Q10 da atividade heterotrófica durante a decomposição aeróbia de Utricularia breviscapa e seu efeito na ciclagem do carbono da lagoa do óleo

In this study the Q10 coefficients of heterotrophic activities were measured during aerobic decomposition of Utricularia breviscapa Wright ex Griseb from Óleo lagoon (21° 36' S and 49° 47' W), Luiz Antonio, SP. The bioassays were set up with fragments of U. breviscapa and incubated with lagoon water at distinct temperatures (15.3, 20.8, 25.7 and 30.3 °C). Periodically for 95 days, the concentrations of dissolved oxygen were determined in the bioassays. The results of the temporal variation of dissolved oxygen were fitted to a first-order kinetic model. The stoichiometric relations were calculated on the basis of these fittings. In general, the results allowed us to conclude: i) the oxygen/carbon stoichiometric relations (O/C) varied in function of temperature and time. The temporal variations of the O/C observed in the decomposition of U. breviscapa, suggest that, in the initial phases of the process, low organic carbon concentrations were enough to generate great demands of oxygen, ii) the oxygen consumption coefficients (k d) presented low variation in function of increasing temperature, iii) the increment of the temperature induced a higher consumption of oxygen (COmax) and iv) the simulations indicate that during summer, temperature activates the metabolism of decomposing microbiota.

Neste estudo, foram discutidos os coeficientes Q10 das atividades heterotróficas durante a decomposição aeróbia de Utricularia breviscapa Wright ex Griseb da lagoa do Óleo (21° 36' S e 47° 49' O), Luiz Antônio, SP. Os bioensaios foram realizados com fragmentos de U. breviscapa e água da lagoa sendo incubados em diferentes temperaturas (15,3, 20,8, 25,7 e 30,3 °C). Periodicamente, por 95 dias, as concentrações de oxigênio dissolvido foram determinadas nos bioensaios. Os resultados da variação temporal de oxigênio dissolvido foram ajustados a um modelo cinético de primeira ordem. As relações estequiométricas foram calculadas com base nesses ajustes. De modo geral, os resultados permitiram concluir: i) as relações estequiométricas (O/C) variaram em função da temperatura e do tempo. As variações temporais dos coeficientes estequiométricos observadas na decomposição de U. breviscapa sugerem que, nas fases iniciais do processo, concentrações baixas de carbono orgânico são suficientes para gerar grandes demandas de oxigênio; ii) os coeficientes de consumo de oxigênio (k d) apresentaram baixa variação em função do incremento da temperatura; iii) o incremento da temperatura induziu um maior consumo de oxigênio (COmáx); e iv) as simulações indicaram que, durante o verão, a temperatura favoreceu o aumento do metabolismo da microbiota decompositora.

Bioremediation of a crude oil - polluted soil by application of fertilizers

Oil pollution is a worldwide threat to the environment and the remediation of oil-contaminated soils, sediments and water is a major challenge for environmental research. Bioremediation is a useful method for soil remediation, if pollutant concentrations are moderate and non-biological techniques are not economical. The bioremediation consists strategy of actively aerating the soils and adding fertilizer in order to promote oil biodegradation by indigenous microorganisms. The objective of this study was to investigate whether agricultural fertilizers [N, P, K] enhance the microbial degradation of petroleum hydrocarbons in soil. Artificially polluted soil with 1% density of crude oil was used and then fertilizers were applied in 3 levels of 0, 1 and 2 ton/ha in 3 replicates. The soils were kept in 30 Degree C and 60 percent of field capacity condition for 5 to 10 weeks. To provide the necessary aeration, the soils were tilled twice a week by shovel. Soil sample were analyzed for hydrocarbon-degrading heterophic bacteria count and some soil chemical properties. Residual oil was measured by oil soxhlet extraction method, and gas chromatography. The results showed that the hydrocarbon-degrading and heterotrophic bacteria count in all the treatments increased with time and heterotrophic bacteria population increased from 6x10[3] cfu/g soil to 1.4x10[8] cfu/g soil. Also, soil C/N ratio decreased from 6 to 3. The results indicated that the applied fertilizer increased the degradation of the hydrocarbons compared with the control. Gas chromatography results showed that normal paraffin and isopernoid [Phitane and Pristane] decreased in the range of 45 to 60 percent in all treatments. Furthermore, the results showed that the application of fertilizers at 2 ton/ha rate in oil-contaminated soil lead to greater rates of biodegradation after 5 weeks indicating the feasibility of bioremediation

prospective study of postanaesthesia recovery room complications. incidence and treatment

To audit the incidence and nature of post-anesthesia recovery room complications, their treatment and review the role of recovery room in modern anesthetic practice. 3151 patients who received general or regional anaesthesia were admitted to the recovery room during six months period [August 01, 1995 to January 31, 1996]. Information noted on forms by recovery nurse by encircling the pre coded complication. Out of 3151 patients, 2716 patient's data forms could be collected. Therefore results reflect 86% of the patients passing through the recovery. The overall incidence of complications in our population was 36.26%.Complications referable to CNS were 52.29%, the commonest of which was pain[51.26%], agitation [0.18%] and excessive drowsiness [1.01%].The second commonest system was GIT[25.07%] nausea [14.31%] and vomiting [12.18%].The third system was CVS [21.52%],bradycardia [5.48%], tachycardia [7.61%],hypertension [4.26%],hypotension [2.53%],myocardial ischaemia [0.81%] myocardia infarction [0.10%] and new arrhythmias [1.41%].The fourth system was Respiratory system [5.58%], hypoventilation [l.42%], bronchospasm [0.81%], laryngospasm [0.1%] and desaturation [Sp02 < 90%] in [0.1%].0.6% patients had to be reintubated. Two patients had oliguria. Miscellaneous complications were [9.94%]. More than one complication was observed in some patients. The incidence of mortality in our study during this period was 0.10%. Every third patient is susceptible to get some form of complications in the immediate post-anesthesia recovery period. It reflects the importance and need of a specialized designated area called recovery room with qualified staff

Comparison of lidocaine vs lidocaine + ketorolac in intravenous regional anaesthesia [bier's block]

To compare the duration of anaesthesia and degree of analgesia during intravenous regional anaesthesia using Lidocaine alone and Lidocaine with Ketorolac. An international quasi experimental study. This study was carried out in Nishtar Hospital Multan from 01/01/2006 to 30/06/2006 [6 Months]. Results: Patients were divided into two groups A and B. In group A injection Lidocaine 0.5% 40ml was given whereas in group B injection Ketorolac 30mg was add to Lidocaine 0.5% 40ml. The degree of anaesthesia and duration of analgesia were compared in both groups. Haemodynamics were also recorded to see any systemic effects of drugs. We conclude that 30mg Ketorolac added to Lidocaine in IVRA increases degree of anaesthesia and also provide prolonged postop analgesia

Effect of fentanyl and epinephrine, alone or together with and without lidocaine on the sensory and motor block duration and hemodynamic variations in spinal anesthesia

Spinal anesthesia due to its simplicity, rapid onset of its effect and low dose of drug administration, is a desirable procedure to anesthetics particularly for lower extremity and lower abdomen operations. Lidocaine is widely used in this method of anesthesia for prolongation of the sensory block. In the method, different drugs are used to prolong the duration of sensory block. Fentanyl and epinephrine are being used widely for this purpose and so far, the effects of these drugs were not compared. Therefore, in this study, the effect of the two drugs, alone or together, with and without lidocaine, on the duration and intensity of sensory and motor block has been investigated. In this double-blinded clinical trial, 60 c and idates for elective surgery of lower abdomen were randomly divided into three equal groups. For spinal anesthesia, the first group was subjected to 50 mg lidocaine plus 0.2 mg epinephrine, the second one to 50 mg lidocaine plus 0.2 mg epinephrine and 20-micro g fentanyl and the third group to 50 mg lidocaine plus 20-micro g fentanyl. Subsequently, the patients in the 3 groups were evaluated and compared for the duration of sensory and motor block and their hemodynamic variations. The data was analyzed using ANOVA and Chi-square tests. Age and sex distribution among the three groups was not significantly different. The mean of sensory block duration in the first, second and third groups were 130.25 +/- 9.05, 133 +/- 32.7 and 116 +/- 14.58 min, respectively with no significant difference. The mean of motor block duration in the first, second and third groups were 120.95 +/- 14.63, 118.75 +/- 25.74 and 107 +/- 18.23 min, respectively. ANOVA test showed no significant difference among the three groups as well. Also, with respect to hemodynamic variation, there was no significant difference among the three groups. Our findings showed that addition of epinephrine and fentanyl and combination of them to the lidocaine had no effect on the duration of sensory and motor block and hemodynamic variations. Therefore, combined use of these drugs is not necessary

Comparison between three low dose combined spinal epidural techniques for caesarean delivery in preeclampsia patients

Combined spinal epidural is an established technique for caesarean delivery. Various local anesthetics and opioids, either alone or in combination, have been used to induce analgesia intrathecally when combined spinal epidural is used. The aim of this study is to evaluate the quality of anesthesia, hemodynamic changes, the amount of fluids and ephedrine needed and the effects on neonatal outcome of combined spinal epidural anesthesia with three different low intrathecal doses of hyperbaric bupivacaine and fentanyl for caesarean delivery in preeclampsia patients. 60 parturients with preoperative diagnosis of preeclampsia were scheduled for elective caesarean section under combined spinal epidural regional technique. After preloading with 500ml Ringer lactate, patients were randomly classified into three groups. Group I: 20 patients who received intrathecal 5mg hyperbaric bupivacaine 0.5% and 20 micro fentanyl, Group II: 20 patients who received 7.5mg hyperbaric bupivacaine 0.5% and 20 micro fentanyl, Group III: 20 patients who received 10 mg hyperbaric bupivacaine 0.5% and 20 micro fentanyl. The three study groups were compared with respect to sensory level, the onset of epidural supplementation, the severity of hypotension, heart rate, the dose of ephedrine and amount of fluids needed and neonatal Apgar score and umbilical cord arterial pH. Sensory level has reached T4 level in the three study group with subsequent satisfactory surgical conditions. Patients in group I, required supplemental epidural dose after 45 +/- 3 minutes, while group II, after 60 +/- 2 minutes, group III, after 70 +/- 3 minutes. The incidence of systolic hypotension was significantly lesser in group I, 30% +/- 5 than group II, 42% +/- 3 and group III, 51% +/- 4. The incidence of diastolic hypotension was also significantly lesser in group I, 32% +/- 3 than group II, 43% +/- 2 and group III, 51% +/- 3. Bradycardia was significantly lower in group I than group II and III, [20% +/- 4, 29% +/- 2, 39% +/- 3] respectively. The total fluids needed was significantly higher in group III, 1500 +/- 300, than group II, 1250 +/- 250 and lower in group I, 1000 +/- 200. The dose of ephedrine was significantly higher in group III, 35 +/- 10mg, than group II, 25 +/- 10mg and lower in group I, 15 +/- 5mg. There was no significant difference between the three study groups as regard Apgar score after 1 and 5 minutes and umbilical cord arterial blood pH. Low dose combined spinal epidural regional technique can achieve satisfactory surgical conditions. Subsequent supplement with epidural dose may be needed. Reducing the intrathecal dose of local anesthetic provides a better hemodynamic consequences and the need of ephedrine and intraoperative fluids are reduced with consequent better fetal outcome

effect of propofol-fentanyl versus sevoflurane-fentanyl on intracranial pressure and cerebral hemodynamics in surgeries for supratentorial mass lesions in children

This study was carried out to compare the effects of sevoflurane-fentanyl versus propofol-fentanyl anesthesia on cerebral hemodynamics and subdural intracranial pressure in children undergoing craniotomy for supratentorial tumors. Forty children, 3-8 years old, with supratentorial tumors resulting in midline shift of 5-10 mm were included in this prospective study. They were randomized into two equal groups. Anesthesia was induced with propofol, fentanyl and atracurium in both groups. In group S anesthesia was maintained with sevoflurane [1-1.5 MAC] in oxygen, while in group p anesthesia was maintained with a continuous intravenous infusion of propofol. Jugular venous bulb blood samples were obtained from a catheter introduced retrogradely into the right internal jugular vein. Intracranial pressure [ICP] was measured through a cannula inserted subdurally and connected via a fluid-filled tubing system to a pressure transducer. Cerebral perfusion pressure [CPP] and arterial- to-jugular venous oxygen difference [AJDO[2]] were calculated. The surgeon manually assessed dural tension prior to dural incision and also assessed the degree of brain swelling after dural incision. Observations were made during normocapnia and moderate hyperventilation. Anesthetic maintenance with propofol-fentanyl resulted in a significantly higher mean arterial pressure [MAP], significantly lower ICP, and significantly higher CPP [p<0.05 for all] compared to sevoflurane-fentanyl. On the other hand, jugular bulb venous oxygen saturation [SjvO[2]] was significantly higher and AJDO[2]] significantly lower in the group S [p<0.05]. Surgeon's assessment of dural tension and brain swelling was significantly more favorable in the group P [p<0.05]. The incidence of probable cerebral hypoperfusion or ischemia tended to be higher in group P but with no significant difference relative to group S. Propofol-fentanyl anesthesia seems to have more favorable effects on cerebral hemodynamics and intracranial pressure than sevoflurane fentanyl anesthesia in children undergoing craniotomy for supratentorial tumors, with no significant side effects on brain oxygenation