To Evaluate the Effectiveness of Magnesium Sulphate as an Agent to induce Hypotensive Anaesthesia in Lumbar Spine Surgery. A Prospective Randomized, Placebo-Control Study

Introduction: This randomized placebo controlled study wasdesigned to evaluate the effectiveness of magnesium sulphateas an agent to induce hypotensive anaesthesia in lumbar spinesurgery.Material and Methods: The study included 100 patients ofboth sexes who were equally distributed in two groups, theGroup Mg(Magnesium sulphate group) and Group C (controlgroup). The Magnesium group received magnesium sulphate40mg/kg administered as a slow IV bolus over a period of 10minutes before induction and 15mg/kg/hr by continuous IVinfusion during surgery. The same volume of isotonic salinewas administered to the control group. Surgical time, heartrate and mean arterial blood pressure was measured.Results: In the magnesium group there was reduction insurgical time (103.54 mins vs 117.34 mins), although theanaesthestic time was 9 minutes longer in the Magnesiumgroup denoting a longer emergence time. The mean arterialpressure and heart rate were significantly reduced inMagnesium group(p<0.005). Postoperative shivering was alsoless in Magnesium group.Conclusion: Magnesium infusion resulted in a steady andsmooth reduction in mean blood pressure and reduced heartrate, with no episodes of severe hypotension. Furthermoremagnesium causes reduction in duration of surgical time andpostoperative shivering

Alpha-adrenergic receptors in PVT neurons promote recovery from propofol anesthesia / 医学研究生学报

Objective The locus coeruleus noradrenergic system regulates the recovery process of general anesthesia, but its mechanism remains unclear. The locus coeruleus has a large amount of projection to the paraventricular nucleus of the thalamus (PVT). This study was to investigate the effect of the α-noradrenergic receptor in PVT neurons in propofol anesthesia. Methods The immunofluorescence technique was used for comparison of the c-fos expression in the PVT neurons collected from male SD rats under propofol anesthesia (the PA group, n = 4) or no anesthesia (the non-PA group, n = 4) and observation of the activity of PVT neurons. PVT microinjection models were established in 40 rats and randomized into four groups of equal number: noradrenaline, phentolamine, propranolol, and isotonic saline. Under propofol anesthesia, the animals received microinjection of noradrenaline, phentolamine, propranolol, and isotonic saline at 1 μL into the PVT, respectively, and were observed for the time of recovery of righting reflex (RORR) and the δ (1-4 Hz), θ (4-8 Hz), α (8-12 Hz), β (12-25 Hz) and γ waves (25-60 Hz) on EEG before and after microinjection. Results The expression of c-fos was significantly reduced in the PA group compared with that in the non-PA control. The Ca2+ signals in the PVT were significantly increased during the propofol induction of the loss of righting reflex (LORR), but decreased in the early stage of and during propofol anesthesia (P < 0.05), and remarkably increased at the emergence of and during RORR (P < 0.05). In comparison with the isotonic saline control, the noradrenaline group showed markedly shortened time of RORR (837.8 s vs 647.7 s, P < 0.05), reduced rate of δ waves (P < 0.05) and elevated rate of β waves (P < 0.05), while the phentolamine group exhibited prolonged time of RORR (837.8 s vs 1045.1 s, P < 0.05) and increased rate of δ waves after microinjection (P < 0.05). Conclusion The α-noradrenergic receptors in PVT neurons play a critical role in promoting recovery from propofol anesthesia.

Genomic Insights into the Rice Blast Fungus through Estimation of Gene Emergence Time in Phylogenetic Context

The rice blast fungus, Magnaporthe oryzae, is an important pathogen of rice plants. It is well known that genes encoded in the genome have different evolutionary histories that are related to their functions. Phylostratigraphy is a method that correlates the evolutionary origin of genes with evolutionary transitions. Here we applied phylostratigraphy to partition total gene content of M. oryzae into distinct classes (phylostrata), which we designated PS1 to PS7, based on estimation of their emergence time. Genes in individual phylostrata did not show significant biases in their global distribution among seven chromosomes, but at the local level, clustering of genes belonging to the same phylostratum was observed. Our phylostrata-wide analysis of genes revealed that genes in the same phylostratum tend to be similar in many physical and functional characteristics such as gene length and structure, GC contents, codon adaptation index, and level of transcription, which correlates with biological functions in evolutionary context. We also found that a significant proportion of genes in the genome are orphans, for which no orthologs can be detected in the database. Among them, we narrowed down to seven orphan genes having transcriptional and translational evidences, and showed that one of them is implicated in asexual reproduction and virulence, suggesting ongoing evolution in this fungus through lineage-specific genes. Our results provide genomic basis for linking functions of pathogenicity factors and gene emergence time.

Bechmarking anesthesia-controlled times at a tertiary general hospital in the Philippines

The need to measure and improve quality in the health care management setting necessitates the development of performance standards. The drive for operating room (OR) efficiency has led administrators to investigate the anesthesia-controlled times (ACTs), which are the specific periods of anesthesia task completion including preparation for anesthetic induction, anesthetic induction itself and the wake up time or time to emergence from anesthesia.OBJECTIVES: This study aims to conduct an internal benchmarking of ACTs using a secondary analysis of the data collected in a cross sectional survey of randomly selected elective surgical cases from October 2011 to January 2012, looking into the efficiency status of the operating room under the Department of Surgery of the Philippine General Hospital (PGH).METHODS: Mean observed times for each of the milestone comprising the ACT were calculated taking in consideration the various anesthetic techniques, type of surgical procedures, duration of the operation and the anesthesiologist's experience. Analysis of variance and Fisher's exact test were used to determine the association of these factors with length of the ACT. For those where an association was noted, a multivariate analysis was done to determine its impact on the actual ACT.RESULTS: Based on data from 539 cases, a set of benchmarks for ACT that better reflects the local setting, is proposed for the different surgical procedures and anesthetic techniques. This includes times for anesthesia preparation of 5 mins, anesthesia induction of 10 minutes and emergence times of 10 mins for total intravenous anesthesia; 20,15 and 15 mins for inhalational anesthesia; 15,10, 10mins for spinal anesthesia; 20, 25, 10 mins for epidural anesthesia and 10, 25, and 15 minutes for combined general-regional anesthesia.CONCLUSION: It is imperative to standardize ATCs in order to reduce variability and improve efficiency. The first step in achieving this goal is to describe the standards in a particular institution, which in turn may be used as a benchmark by other institutions in a similar setting.