35 research outputs found
The study of relationship between post dural puncture headache and hemodynamic fluctuation in patients undergoing spinal anesthesia
زمینه و هدف: به اعتقاد بسیاری از محققین علت بروز سردرد بعد از سوراخ شدن سخت شامه، نشت مایع مغزی نخاعی (CSF= Cerebrospinal Fluid) و کاهش فشار داخل مغز (ICP= Intracranial Pressure) است. تغییرات همودینامیک می تواند بر دینامیک CSF و وضعیت ICP تأثیر گذار باشد. مطالعه حاضر با هدف تعیین ارتباط نوسانات فشار خون، نبض، میزان مایع دریافتی و افدرین مصرفی با سردرد بعد از سوراخ شدن سخت شامه طراحی و اجراء شده است. روش بررسی: این مطالعه به صورت توصیفی - تحلیلی بر روی 95 بیمار با شکستگی ساق پا، نامزد بیهوشی نخاعی، با استفاده از سوزن نوعQuincke شماره 23 انجام شد. فشار خون و نبض در دقایق 1، 2، 4، 8 و 16 پس از انجام بیهوشی نخاعی اندازه گیری و ثبت شد. همچنین جمع مایع وریدی و افدرین دریافتی نیز محاسبه و ثبت گردید. سپس بروز، شدت (بر اساس پرسشنامه VAS=Visual Analog Scale) و مدت سردرد (روز) تا 5 روز بعد از انجام بیهوشی مورد بررسی قرار گرفت. در پایان ارتباط میزان بروز و شدت سردرد با نوسانات فشار خون، نبض، میزان مایع وریدی دریافتی و افدرین مصرفی با استفاده از آزمون های t مستقل و پیرسون مورد تجزیه و تحلیل قرار گرفت. یافته ها: از بیماران مورد مطالعه 3/33 دچار سردرد بعد از سوراخ شدن دورا شدند. میانگین شدت و طول مدت سردرد به ترتیب 11/2±83/5 (سانتیمتر) و 40/1±66/3 (روز) بود. بین درصد نوسانات فشارخون سیستول، دیاستول، متوسط شریانی، تعداد نبض، میزان مایع دریافتی و افدرین مصرفی با میزان بروز و شدت سردرد متعاقب بیهوشی نخاعی، رابطه معنی داری بدست نیامد. نتیجه گیری: عدم ارتباط معنی دار بین نوسانات همودینامیکی با میزان بروز و شدت سردرد می تواند نشان دهنده این موضوع باشد که علیرغم تأثیر عوامل همودینامیک بر دینامیک و وضعیت ICP، این عوامل احتمالاَ از قدرت کافی جهت تغییر در میزان نشت CSF از سوراخ دورا برخوردار نبوده و عامل تعیین کننده اصلی همان اندازه و شکل سوراخ ایجاد شده توسط سوزن های نخاعی است
The experimental investigation of hardness and wear behaviors of inner surface of the resin tubes reinforced by fibers
Resin tubes made of epoxy base material and fibers are widely used in the transportation, and aeronautics industries due to their high mechanical properties. Different reinforcing fibers and resins are usually used in making these tubes and lead to various properties. In this study, tubes made by using a 45-degree unilateral winding method and reinforced by Glass, Carbon, and Kevlar fibers and their hardness and wear behaviors were investigated. The results showed that the highest hardness was obtained for the carbon fiber reinforced composite tube (CFR), equal to 65HV, which was 109% more than the Kevlar fiber reinforced composite tube (KFR). Higher hardness indicates greater resistance of the material to local deformation and also stronger bonding between the base material and the reinforcing fibers. The wear test results showed that the wear rate of CFR was 6 mg/m, which was 26% and 55% lower than the glass fiber reinforced composite tube (GFR) and KFR, respectively. The obtained result can be explained as a result of good bonding and compatibility between carbon fibers and used resin. Scanning electron microscope (SEM) images were taken to evaluate the results
The experimental analysis of creep and corrosion properties of polymeric tube reinforced by glass, carbon and Kevlar fibers
Polymeric tubes, including epoxy and reinforcing fibers, are widely used in the petroleum and aerospace industries due to their high strength and corrosion resistance. In this study, corrosion and creep properties of resin-based tubes reinforced by Glass fibers (GFR), Carbon fibers (CFR), and Kevlar fibers (KFR) were investigated using tubes made by using a 45-degree unilateral winding method. The highest creep strain was obtained for the CFR equal to 0.7445 and the lowest was obtained for KFR with the Kevlar fibers being severely damaged. The lowest corrosion rate per year was for the CFR sample, equal to 113in/year×1000. The corroded samples were subjected to a tensile test and a 2%improvement in ultimate tensile strength was achieved for GFR. To evaluate the results and the quality of adhesions between fibers and resins, SEM images were taken of the samples
The effect of bleaching on microhardness of silorane-based composite resins
Introduction: Bleaching treatments may negatively affect the surface quality of composite restorations existing in the mouth. This study sought to assess the effect of 16% and 35% carbamide peroxide on microhardness of silorane-based versus two methacrylate-based composite resins.
Methods: A total of 54 discs were fabricated from FiltekP90 (P90), FiltekZ350XT(Z350) Enamel and Filtek Z250(Z250) (n=18). Each group of composite specimens was randomly divided into 3 subgroups (n=6). The control subgroup was stored in distilled water for 2 weeks. Subgroup 2 specimens were bleached 4hours a day with 16% carbamide peroxide (Home bleaching) for 14 days. The 3rd subgroup specimens were subjected to 35% carbamide peroxide (Office bleaching) applied once for 40 minutes. Microhardness of specimens was measured before and after bleaching by using Vickers hardness testing machine. Data were analyzed by using Repeated Measures ANOVA.
Results: Baseline microhardness of P90 was lower than that of the other two composite resins (p=0.001). Bleaching decreased the microhardness of Z250 and Z350 compared to the control group (p<0.001). However, in P90, only the office bleaching material caused a reduction in microhardness (p=0.009). The effect of home and office bleaching on microhardness of P90 was different (p=0.015).
Conclusion: Bleaching treatments significantly decreased the microhardness of Z250 and Z350 composite resins but this reduction in P90 was not statistically significant after home bleaching
The global burden of adolescent and young adult cancer in 2019 : a systematic analysis for the Global Burden of Disease Study 2019
Background In estimating the global burden of cancer, adolescents and young adults with cancer are often overlooked, despite being a distinct subgroup with unique epidemiology, clinical care needs, and societal impact. Comprehensive estimates of the global cancer burden in adolescents and young adults (aged 15-39 years) are lacking. To address this gap, we analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, with a focus on the outcome of disability-adjusted life-years (DALYs), to inform global cancer control measures in adolescents and young adults. Methods Using the GBD 2019 methodology, international mortality data were collected from vital registration systems, verbal autopsies, and population-based cancer registry inputs modelled with mortality-to-incidence ratios (MIRs). Incidence was computed with mortality estimates and corresponding MIRs. Prevalence estimates were calculated using modelled survival and multiplied by disability weights to obtain years lived with disability (YLDs). Years of life lost (YLLs) were calculated as age-specific cancer deaths multiplied by the standard life expectancy at the age of death. The main outcome was DALYs (the sum of YLLs and YLDs). Estimates were presented globally and by Socio-demographic Index (SDI) quintiles (countries ranked and divided into five equal SDI groups), and all estimates were presented with corresponding 95% uncertainty intervals (UIs). For this analysis, we used the age range of 15-39 years to define adolescents and young adults. Findings There were 1.19 million (95% UI 1.11-1.28) incident cancer cases and 396 000 (370 000-425 000) deaths due to cancer among people aged 15-39 years worldwide in 2019. The highest age-standardised incidence rates occurred in high SDI (59.6 [54.5-65.7] per 100 000 person-years) and high-middle SDI countries (53.2 [48.8-57.9] per 100 000 person-years), while the highest age-standardised mortality rates were in low-middle SDI (14.2 [12.9-15.6] per 100 000 person-years) and middle SDI (13.6 [12.6-14.8] per 100 000 person-years) countries. In 2019, adolescent and young adult cancers contributed 23.5 million (21.9-25.2) DALYs to the global burden of disease, of which 2.7% (1.9-3.6) came from YLDs and 97.3% (96.4-98.1) from YLLs. Cancer was the fourth leading cause of death and tenth leading cause of DALYs in adolescents and young adults globally. Interpretation Adolescent and young adult cancers contributed substantially to the overall adolescent and young adult disease burden globally in 2019. These results provide new insights into the distribution and magnitude of the adolescent and young adult cancer burden around the world. With notable differences observed across SDI settings, these estimates can inform global and country-level cancer control efforts. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe
The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019
Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Paravertebral block using bupivacaine with/without fentanyl on postoperative pain after laparoscopic cholecystectomy: A double-blind, randomized, control trial
Background: Postoperative pain is one of the most common complaints after elective laparoscopic cholecystectomy. The present study was aimed to evaluate the effect of paravertebral block using bupivacaine with/without fentanyl on postoperative pain and complications after laparoscopic cholecystectomy.
Materials and Methods: This study was done on 90 patients scheduled to undergo elective laparoscopic cholecystectomy. Patients were assessed in two groups: The case group received bupivacaine and fentanyl, and the control group received bupivacaine and normal saline. Primary outcomes were severity of postoperative pain at rest and during coughing. Secondary outcomes were postoperative cumulative morphine consumption and the incidence of side-effects.
Results: Pain score at rest before surgery, after recovery, hour-1 and hour-6 was not significantly different between the groups. But in hour-24 cases, the pain score during coughing was significantly higher than controls. Severity of pain at rest in time points was not different between groups. The frequencies (%) of moderate pain at mentioned times in case and control groups were 64, 31, 16, 9, 0 versus 67, 16, 7, 4, and 0, respectively. Pain score during coughing was lower in controls at hour-24 in comparison with cases, but in other time points was not significant. The control group significantly received more total dose of morphine in comparison with cases group. Nausea, vomiting and hypotension were similar in groups, but pruritus was significantly different between the groups.
Conclusion: Adding fentanyl to bupivacaine in paravertebral block did not significantly improve the postoperative pain and complications after laparoscopic cholecystectomy. However, further studies are needed to be done
The Comparison of Preventive Analgesic Effects of Ketamine, Paracetamol and Magnesium Sulfate on Postoperative Pain Control in Patients Undergoing Lower Limb Surgery: A Randomized Clinical Trial
Background: In considering the importance of postoperative pain management and its consequences on its related secondary outcomes including nausea, vomiting, and operation-related complications, we aimed to compare the effectiveness of the three analgesic agents including ketamine, paracetamol, and magnesium sulfate for postoperative pain relief and associated consequences in this trial. Materials and Methods: In this double-blinded randomized control clinical trial, patients scheduled for elective lower extremity orthopedic surgery under general anesthesia were enrolled and randomized into four groups for receiving intravenous ketamine (0.25 mg/kg), paracetamol (15 mg/kg), magnesium sulfate (7.5 mg/kg), and placebo (normal saline), immediately after the induction of anesthesia. Postoperative pain scores, analgesic, and metoclopramide use, and frequency of vomiting and satisfaction score of studied patients in the four studied groups during the 6 h, 6–12 h, and 12–24 h after recovery were recorded and compared. Results: In this trial, thirty patients randomized in each studied groups. Mean of postoperative pain score was significantly lower in ketamine group than others during 24 h after recovery (P 0.05). Excellent and good satisfaction score were significantly higher in ketamine group than other groups (P = 0.04). Conclusions: Ketamine has more superior effect for during recovery and postoperative pain controlling and analgesic use than paracetamol and magnesium sulfate
EFFECT OF NITROUS OXIDE INHALATION ON CHANGES IN SENSORY BLOCK IN PATIENTS UNDERGOING SPINAL ANESTHESIA
Introduction: Spinal Anesthesia is a successful method for most surgical procedures on lower extremities and lower abdomen. Occasionally the duration of sensory blockade is shorter than the duration of the surgical procedures resulting in painful stress and discomfort. In one research, inhalation of N2O during spinal anesthesia provided analgesic effects and enhanced the level of sensory blockade. Our study evaluated the effects of N2O on the duration of sensory blockade in spinal anesthesia. Methods: In this double blind randomized controlled clinical trial, 80 adult patients who were candidates for lower extremity or lower abdominal surgery were randomly divided into two group received 500k N2O plus 50% O2 by inhalation and control group received 02 without N2O. Block level and the duration of T6 and T10 blockade were determined mean, systolic and diastolic blood pressures and heart rate recorded. Statistical analysis was performed by t-test. Results: The duration of sensory blockade above T6 and T10 levels in patients receiving N2O plus O2 was significantly superior to that in the control group (P < 0.05). The mean changes in the heart rate and systolic, diastolic, and mean arterial blood pressures, were not significantly different between two groups. Discussion: Our results, show that N2O inhalation during spinal anesthesia enhances the duration of sensory block making this technique more piratical and appropriate. It also provided move homodynamic stability any adverse effects