Spinal Anaesthesia Failure Risk Followed by Failed Epidural Block in Caesarean Deliveries

Background: There is a risk associated with spinal anaesthesia failure after immediate deliverance of epidural anaesthesia. Objective: To assess the risk of spinal anaesthesia failure followed by failed epidural block in caesarean deliveries. Study Design: Retrospective study Place and Duration of Study: Department of Obstetrics & Gynaecology, Khairpur Medical College Khairpur Mir’s from 1st July 2020 to 30th June 2021. Methodology: One hundred and seventy labour cases who have been given epidural anaesthesia and were prepared for caesarean section through spinal anaesthesia were included. The demographic and clinical information of each pregnant female was documented. Proper epidural dosage was maintained during labour. Results: The mean age of the patients was 26.5±5.2 years. There was a significant increase in body mass index among epidural converted spinal aesthesia patients. The higher incidence of non-reassuring foetal heart tracing and malpresentation in failure cases were found. Conclusion: There is a 11.17% risk of spinal anaesthetics failure for attaining block height when administered within 30 min of epidural dose. Keywords: Epidural, Spinal anaesthesia, Anaesthesia, Caesarean

The effect of the geometric structure of the modified slot die on the air field distribution in the meltblowing process

In order to reduce the fiber diameter and the energy consumption in the meltblowing process, a modified slot die with two blocks was designed in this article. The numerical calculation and the experimental verification of the airflow field under the modified slot die were carried out, and the effect of the block structure parameters on the air field was investigated. The research results indicate that compared to the common slot die, the modified slot die with the blocks could increase the velocity on the spinning line and reduce the rate of the temperature decay on the spinning line. When the block width and the block inclination angle lower, and the block height expands, it could increase the peak of the air velocity, the temperature and the turbulence intensity on the center line of the air field under the modified slot die. The average velocity on the spinning line of the modified die under the conditions of block width = 20 mm, block height = 30 mm and block inclination angle = 60° is the highest.

Research on “Cylinder-Four-Beam” Microstructure Improvement of MEMS Bionic Vector Hydrophone

The existing MEMS bionic vector hydrophone has the problems of low-sensitivity and narrow-working band, and the sensitivity and working bandwidth cannot be improved simultaneously by changing the single microstructural parameter. In this paper, the MEMS bionic vector hydrophone microstructural parameters (length, width and height of cantilever, side length of the center block, height and radius of the rigid cylinder) have been optimized simultaneously to obtain a higher sensitivity at the almost same working bandwidth. Firstly, through the mechanical analysis of the microstructure, the objective function and feasible region are established to optimize the parameters of the microstructure, and a set of optimized parameters is obtained. Secondly, the optimized structure is verified by ANSYS simulation, and then, the optimized four-beam structure is fabricated by the MEMS manufacturing technology. Finally, these two kinds of hydrophones (the previous one and the optimized one) are produced, and their performance tests are carried out. The testing results show that the performances of the optimized hydrophone have been greatly improved, exhibiting a receiving sensitivity of −181.2 dB@1 kHz (increasing by 6.5 dB, 0 dB reference 1 V/μ Pa), the frequency response ranging from 20 Hz to 1 kHz which is the same working bandwidth as before, and a good dipole directivity. The optimization researches in this paper provide a method and idea for the performance improvement of the following MEMS vector hydrophone.

Anthropometric Profile of FIVB Volleyball Girls' U18 World Championship Volleyball Players According to the Playing Position- World Championship 2017

Identifying the anthropometric characters of adolescent elite players may be useful in developing the recognition of volleyball talents and key physical abilities needed to perform at a high level. The purpose of this study was to describe anthropometric characteristics, including height, weight, body mass index (BMI), spike height, and block height in elite volleyball youth players participating in the 2017 FIVB Volleyball Girls' U18 World Championship. Also, comparisons of these parameters were evaluated based on individual game position (libero, setter, middle blocker, outside hitter, opposite), team continent, and team rank. The variables studied in this study were extracted from the list of players registered on the website of the International Volleyball Federation (FIVB) and included 240 players of 20 teams. The results of one-way ANOVA showed that players in the G1 group (rank 1 to 4) had higher height, weight, spike height, and block height than other groups (rank 5 to 20). Also, the middle blockers had the tallest height (185.9 cm), weight (71.4 kg), spike height (294.5 cm) and block height (282.7 cm). This study presents anthropometric data that show different levels of success for elite girls' volleyball players in the 2017 championship. This information should serve as a reference for average body height, weight, BMI, spike height, and block height for identifying athletic talents for various positions in volleyball.

Sensory block level prediction of spinal anaesthesia with 0.5% hyperbaric bupivacaine: a retrospective study

There is still no consensus on how to determine the dose of spinal anaesthesia with adequate sensory block for a planned surgery. This retrospective study aimed to explore the associations of miscellaneous factors with peak sensory block level after spinal anaesthesia with hyperbaric bupivacaine, and to construct a predictive model for single-shot spinal anaesthesia. We collected the records of 401 non-pregnant adults who underwent spinal anaesthesia with 0.5% hyperbaric bupivacaine at the L3–4 or L4–5 intervertebral space for lower body surgeries. Multiple linear regression analysis was used to investigate predictors of the block level and build up the predictive model. Five variables were identified as independent predictors of the peak sensory block level, including bupivacaine dose, height, weight, gender and age. The predictive model for peak block level after spinal anaesthesia could be expressed as a formula with these five variables and the estimated predictive power was 0.72. Based on this model, it is possible to determine a reasonable dose of hyperbaric bupivacaine for spinal anaesthesia, which gives adequate sensory block required for diverse surgical procedures in various patients and could be considered as a dose reference for sensory block height in spinal anaesthesia.

An Investigation of the Quantitative Correlation between Urban Spatial Morphology Indicators and Block Wind Environment

The research purpose of this work is guiding the spatial morphological design of blocks via relevant indicators to realize suitable wind environments. In doing so, it is necessary to find the most suitable indicator types and value ranges for each urban spatial morphology. At present, most of the relevant research has been based on the numerical simulation of ideal block shapes and rarely proposes results based on actual block types, which often tend to be complex environments. Therefore, this paper firstly presents a theoretical speculation on the main factors influencing indicator effectiveness via analyzing physical significance and formulating principles for each indicator. These speculations are verified via wind environment measurement and statistical analysis, indicating that porosity (P0) can be used as an important indicator to guide the design of block wind environments in the case of deep street canyons, while frontal area density (λF) can be used as a supplement in shallow street canyons with no height differences. Finally, computational fluid dynamics (CFD) is used to quantify the impact of block height difference and street canyon depth on λF and P0, thereby finding suitable types of urban form and value ranges for λF and P0. This paper provides a feasible wind environment index system for urban designers.

BLOCK SLOPE IS THE MAIN DETERMINANT OF BLOCK PHASE PERFORMANCE IN SWIMMING

ABSTRACT Introduction Swimming starts are an important component for decreasing the total race time, especially in short events. In this phase of swimming, the aim is to increase performance using many different techniques and starting platforms. Objectives The effects of height and slope of the starting block on kick-start performance were assessed in this study. Methods Six male competitive swimmers performed 24 kick-starts using four block settings: 65 cm & 75 cm flat and 65 cm & 75 cm sloped. Two-dimensional kinetic and three-dimensional kinematic data were analyzed, including average and maximum horizontal/vertical forces and impulses; reaction times; movement and block times; and take-off vertical/horizontal velocities. Two-way within-subject design ANOVAs were implemented to test the effects of block height and slope on the kinetic and kinematic variables. Results Block slope was the main factor affecting most of the dependent variables. Shorter block and movement times, greater average and maximum vertical forces, vertical impulse, and maximum horizontal force were found for the sloped settings. An inverse relationship was found between block height and 0-5 m times. Conclusion Based on the results, blocks with height of 75 cm and slope of 10° provided better results in swimmers’ performance in the block phase. Level of evidence II, Therapeutic Studies -Investigating the Results of Treatment

Sensory Block Level Prediction of Spinal Anaesthesia With 0.5% Hyperbaric Bupivacaine: A Retrospective Study

There is still no consensus on how to determine the dose of spinal anaesthesia with adequate sensory block for a planned surgery. This retrospective study aimed to explore the associations of miscellaneous factors with peak sensory block level after spinal anaesthesia with hyperbaric bupivacaine, and to construct a predictive model for single-shot spinal anaesthesia. We collected the records of 401 non-pregnant adults who underwent spinal anaesthesia with 0.5% hyperbaric bupivacaine at the L3-4 or L4-5 intervertebral space for lower body surgeries. Multiple linear regression analysis was used to investigate predictors of the block level and build up the predictive model. Five variables were identified as independent predictors of the peak sensory block level, including bupivacaine dose, height, weight, gender and age. The predictive model for peak block level after spinal anaesthesia could be expressed as a formula with these five variables and the estimated predictive power was 0.72. Based on this model, it is possible to determine a reasonable dose of hyperbaric bupivacaine for spinal anaesthesia, which gives adequate sensory block required for diverse surgical procedures in various patients and could be considered as a dose reference for sensory block height in spinal anaesthesia.

Dural puncture epidural analgesia for labor: a randomized comparison between 25-gauge and 27-gauge pencil point spinal needles

BackgroundThis double-blind, randomized trial compared dural puncture epidural analgesia (DPEA) for labor using 25-gauge and 27-gauge pencil point spinal needles. We hypothesized that both needle sizes would result in similar onset time (equivalence margin=2.5 min) and therefore designed the study as an equivalence trial.MethodsOne hundred and forty patients undergoing labor were randomized to DPEA with 25-gauge (n=70) or 27-gauge (n=70) pencil point spinal needles. After the placement of the epidural catheter, a bolus of 20 mL of bupivacaine 0.125% and fentanyl 2 µg/mL was administered to all subjects. Thereafter, patients received boluses of 12 mL of bupivacaine 0.125% every 2 hours as needed.A blinded investigator recorded the onset time (defined as the temporal interval required to achieve a pain score ≤1 on a 0–10 scale), S2 block, sensory block height (30 min after the initial bolus of local anesthetic), presence of motor block (30 min after the initial bolus of local anesthetic), number of top-up doses required during labor and incidence of postural headache.ResultsOut of the 140 recruited patients, 135 were retained for analysis. Compared with their 27-gauge counterparts, 25-gauge pencil point spinal needles provided a 1.6 min shorter DPEA onset (95% CI of the difference of the means: −3.2 to −0.1 min). However, there were no intergroup differences in terms of S2 block, sensory block height, motor block, number of top-up doses and incidence of postural headache.ConclusionDural puncture epidural analgesia with 25-gauge pencil point spinal needles provides a 1.6 min shorter onset time than DPEA with 27-gauge spinal needles. Although statistically significant, such a difference may not be clinically relevant. Further investigation is required to compare 25-gauge and 27-gauge spinal needles for DPEA in the setting of different local anesthetic infusion strategies.Trial registration numberNCT03389945.