Hydroclimatic changes on multiple timescales since 7800 y BP in the winter precipitation-dominated Central Asia.

Central Asia (CA) is one of the world's most significant arid regions, which is markedly impacted by global warming. A better understanding of the dynamical processes governing its Holocene climate variability is critical for a better understanding of possible future impacts of climate change in the region. To date, most of the existing CA paleoclimate records are from the summer precipitation-dominated eastern CA (ECA), with few records from the winter precipitation-dominated western CA (WCA). Here, we present a precisely dated (~6‰) and highly resolved (<4-y) record of hydroclimatic variations from the WCA covering the period between 7,774 and 656 y BP. Utilizing multiple proxies (δ18O, δ13C, and Sr/Ca) derived from a stalagmite from the Fergana Valley, Kyrgyzstan, we reveal a long-term drying trend in WCA, which is in contrast with the wetting trend in ECA. We propose that different responses of winter and summer westerly jets to seasonal solar insolation over the past 8,000 y may have resulted in an antiphased precipitation relationship between the WCA and ECA. Our data contain dominant quasiperiodicities of 1,400, 50 to 70, and 20 to 30 y, indicating close connections between the WCA climate and the North Atlantic. We further identified a series of droughts and pluvials on centennial-to-decadal timescales, which may have influenced regional societies and trans-Eurasian culture exchanges during historical and prehistorical times.

Protracted Indian monsoon droughts of the past millennium and their societal impacts.

Protracted droughts lasting years to decades constitute severe threats to human welfare across the Indian subcontinent. Such events are, however, rare during the instrumental period (ca. since 1871 CE). In contrast, the historic documentary evidence indicates the repeated occurrences of protracted droughts in the region during the preinstrumental period implying that either the instrumental observations underestimate the full spectrum of monsoon variability or the historic accounts overestimate the severity and duration of the past droughts. Here we present a temporally precise speleothem-based oxygen isotope reconstruction of the Indian summer monsoon precipitation variability from Mawmluh cave located in northeast India. Our data reveal that protracted droughts, embedded within multidecadal intervals of reduced monsoon rainfall, frequently occurred over the past millennium. These extreme events are in striking temporal synchrony with the historically documented droughts, famines, mass mortality events, and geopolitical changes in the Indian subcontinent. Our findings necessitate reconsideration of the region's current water resources, sustainability, and mitigation policies that discount the possibility of protracted droughts in the future.

Timing and structure of the Younger Dryas event and its underlying climate dynamics.

The Younger Dryas (YD), arguably the most widely studied millennial-scale extreme climate event, was characterized by diverse hydroclimate shifts globally and severe cooling at high northern latitudes that abruptly punctuated the warming trend from the last glacial to the present interglacial. To date, a precise understanding of its trigger, propagation, and termination remains elusive. Here, we present speleothem oxygen-isotope data that, in concert with other proxy records, allow us to quantify the timing of the YD onset and termination at an unprecedented subcentennial temporal precision across the North Atlantic, Asian Monsoon-Westerlies, and South American Monsoon regions. Our analysis suggests that the onsets of YD in the North Atlantic (12,870 ± 30 B.P.) and the Asian Monsoon-Westerlies region are essentially synchronous within a few decades and lead the onset in Antarctica, implying a north-to-south climate signal propagation via both atmospheric (decadal-time scale) and oceanic (centennial-time scale) processes, similar to the Dansgaard-Oeschger events during the last glacial period. In contrast, the YD termination may have started first in Antarctica at ∼11,900 B.P., or perhaps even earlier in the western tropical Pacific, followed by the North Atlantic between ∼11,700 ± 40 and 11,610 ± 40 B.P. These observations suggest that the initial YD termination might have originated in the Southern Hemisphere and/or the tropical Pacific, indicating a Southern Hemisphere/tropics to North Atlantic-Asian Monsoon-Westerlies directionality of climatic recovery.

Trajectory of Serum Bilirubin Predicts Spontaneous Recovery in a Real-World Cohort of Patients With Alcoholic Hepatitis.

BACKGROUND AND AIMS: Alcoholic hepatitis (AH) is a severe condition with poor short-term prognosis. Specific treatment with corticosteroids slightly improves short-term survival but is associated with infection and is not used in many centers. A reliable method to identify patients who will recover spontaneously will minimise the numbers of patients who experience side effects of available treatments. METHODS: We analysed the trajectory of serum bilirubin concentration over the course of hospital admissions in patients with AH to predict spontaneous survival and the need for treatment. RESULTS: data from 426 patients were analysed. Based on bilirubin trajectory, patients were categorized into three groups: 'fast fallers' (bilirubin <0.8 x admission value at day 7), 'static' (bilirubin of >0.9 - <1.2 x admission value) and 'rapid risers' (bilirubin of ≥1.2 x admission bilirubin). Fast fallers had significantly better 90-day survival compared to other groups (log rank p < .001), and showed no benefit of corticosteroid therapy (OR for survival at 28 days of treatment, 0.94, 95% CI 0.06 - 8.41). These findings remained even amongst patients with severe disease based on initial DF, GAHS or MELD scores. CONCLUSIONS: We present an intuitive method of classifying patients with AH based on the trajectory of bilirubin over the first week of admission. It is complimentary to existing scores that identify candidates for corticosteroid treatment or assess response to treatment. This method identifies a group of patients with AH who recover spontaneously and can avoid corticosteroid therapy.

The Asian monsoon over the past 640,000 years and ice age terminations.

Oxygen isotope records from Chinese caves characterize changes in both the Asian monsoon and global climate. Here, using our new speleothem data, we extend the Chinese record to cover the full uranium/thorium dating range, that is, the past 640,000 years. The record's length and temporal precision allow us to test the idea that insolation changes caused by the Earth's precession drove the terminations of each of the last seven ice ages as well as the millennia-long intervals of reduced monsoon rainfall associated with each of the terminations. On the basis of our record's timing, the terminations are separated by four or five precession cycles, supporting the idea that the '100,000-year' ice age cycle is an average of discrete numbers of precession cycles. Furthermore, the suborbital component of monsoon rainfall variability exhibits power in both the precession and obliquity bands, and is nearly in anti-phase with summer boreal insolation. These observations indicate that insolation, in part, sets the pace of the occurrence of millennial-scale events, including those associated with terminations and 'unfinished terminations'.

Meta-analysis and trial sequential analysis of robotic versus laparoscopic total mesorectal excision in management of rectal cancer.

BACKGROUND: We aimed to evaluate comparative outcomes of robotic and laparoscopic total mesorectal excision (TME) in patients with rectal cancer. METHODS: We systematically searched electronic data sources with application of combination of free text and controlled vocabulary search adapted to thesaurus headings, search operators, and limits. Perioperative clinical and short-term oncological outcomes were evaluated. Trial Sequential Analysis of the outcomes was conducted. RESULTS: Nine randomised-controlled trials reporting 1463 patients evaluating outcomes of robotic TME (n = 728) and laparoscopic TME (n = 735) were included. Although the robotic approach was associated with significantly longer operative time (MD 31.64, P = 0.002), it was associated with significantly longer DRM (MD 0.8, P = 0.004) and shorter time to soft diet (MD - 0.50, P = 0.03) compared to the laparoscopic approach. Moreover, there was no significant difference in intraoperative (RR 1.07, P = 0.76)) and postoperative (RR 0.97, P = 0.81) complications, anastomotic leak (RR 0.93, P = 0.69), conversion to open rate (RR 0.46, P = 0.05), blood loss (MD 19.65, P = 0.74), time to first flatus (MD - 0.30, P = 0.37), LARS (RR 0.83, P = 0.41), ileus (RR 0.72, P = 0.39), positive CRM (RR 0.82, P = 0.49), PRM (MD - 0.5, P = 0.55), number of harvested lymph nodes (MD 0.33, P = 0.58), or length of stay (MD - 0.60, P = 0.12) between two groups. The Trial Sequential Analysis demonstrated that the risk of type 1 and type 2 errors was minimal in most outcomes. CONCLUSIONS: Moderate-quality evidence suggested that robotic and laparoscopic TME may be comparable in terms of clinical and short-term oncological profile but the robotic approach may be associated with longer procedure time. Future high-quality randomised studies are encouraged to compare the functional, long-term oncological, and cost-effectiveness outcomes of both approaches.

Efficacy of topical agents for prevention of postoperative sore throat after single lumen tracheal intubation: a Bayesian network meta-analysis.

BACKGROUND: The optimal choice of prophylactic drugs to decrease postoperative sore throat is unclear. The objective of this network meta-analysis (NMA) was to compare and rank 11 topical agents used to prevent postoperative sore throat. METHODS: Various databases were searched independently for randomized-controlled trials (RCTs) comparing topical agents used for the prevention of postoperative sore throat. Inclusion criteria were parallel group studies comparing intervention with active or inactive control and reporting postoperative sore throat. The primary outcome was postoperative sore throat at 24 hr. Secondary outcomes were early sore throat at 4-6 hr, cough, and hoarseness at 24 hr. RESULTS: Evidence was synthesized from 70 RCTs reporting 7,141 patients. Topical application of lidocaine, corticosteroids, ketamine, magnesium, benzydamine, water-based lubricant, and liquorice applied along the tracheal tube, to the tracheal tube cuff, gargled or sprayed were compared with intracuff air and each other. Bayesian NMA showed that magnesium (odds ratio [OR], 0.10; 95% credible interval [CrI], 0.03 to 0.26), liquorice (OR, 0.14; 95% CrI, 0.03 to 0.55), and steroid application (OR, 0.11; 95% CrI, 0.06 to 0.22) most effectively prevented postoperative sore throat at 24 hr. Topical lidocaine was the least effective intervention. CONCLUSION: Topical application of magnesium followed by liquorice and corticosteroids most effectively prevented postoperative sore throat 24 hr after endotracheal intubation.

RéSUMé: CONTEXTE: Le choix optimal des médicaments prophylactiques pour réduire les maux de gorge postopératoires n'est pas clair. L'objectif de cette méta-analyse en réseau (NMA) était de comparer et classifier 11 agents topiques utilisés pour prévenir les maux de gorge postopératoires. MéTHODE: Des recherches ont été réalisées dans plusieurs bases de données de façon indépendante afin d'en extraire les études randomisées contrôlées (ERC) comparant des agents topiques utilisés pour la prévention des maux de gorge postopératoires. Nos critères d'inclusion étaient des études de groupes parallèles comparant une intervention à un témoin actif ou inactif sur des résultats de maux de gorge postopératoires. Le critère d'évaluation principal était les maux de gorge postopératoires à 24 h. Les critères d'évaluation secondaires comprenaient les maux de gorge précoces à 4-6 h, la toux et l'enrouement à 24 h. RéSULTATS: Les données probantes ont été synthétisées à partir de 70 ERC portant sur 7141 patients. L'application topique de lidocaïne, de corticostéroïdes, de kétamine, de magnésium, de benzydamine, d'un lubrifiant à base d'eau et de la réglisse, appliqués le long du tube endotrachéal, sur le ballonnet du tube endotrachéal, en gargarisme ou en vaporisation, ont été comparées à l'air intra-ballonnet et entre les divers agents. La NMA bayésienne a démontré que l'application de magnésium (rapport de cotes [RC], 0,10; intervalle de crédibilité [CrI] 95 %, 0,03 à 0,26), de réglisse (RC, 0,14; CrI 95 %, 0,03 à 0,55) et de stéroïdes (RC, 0,11; CrI 95 %, 0,06 à 0,22) étaient les méthodes plus efficaces pour prévenir les maux de gorge postopératoires à 24 h. La lidocaïne topique était l'intervention la moins efficace à 24 h. CONCLUSION: L'application topique de magnésium, suivie de celle de réglisse et de corticostéroïdes, est l'approche qui prévient le plus efficacement les maux de gorge postopératoires 24 h après une intubation endotrachéale.

Perioperative antiemetic efficacy of dexamethasone versus 5-HT3 receptor antagonists: a meta-analysis and trial sequential analysis of randomized controlled trials.

BACKGROUND: Dexamethasone has many desirable pharmacologic properties for perioperative use. Its antiemetic potential has been a focus of many recent trials. METHODS: Trials comparing dexamethasone to 5-HT3-receptor antagonists (5HT3-RA) for 24 h postoperative vomiting incidences published till August 2017 were searched in the medical database. Comparisons for antiemetic efficiency variables (vomiting incidence, nausea incidence, rescue antiemetic need, and patients with complete response) during early (until 6 h) and late postoperative phase were made. Comparative analgesic requirements were also evaluated. RESULTS: Twenty randomized controlled double-blinded trials were included in the final analysis. Twenty-four-hour vomiting incidence was similar (Fixed-effects, P = 0.86, I2 = 2.94%). Trial sequential analysis (TSA) confirmed non-inferiority of dexamethasone for 24-h vomiting incidence. (α = 5%, ß = 20%, δ = 10%) with "information size" being 1619 (required > 573). Equivalence was also verified from early and delayed nausea rate as well using TSA. Pooled results did not demonstrate superiority/inferiority of 5-HT3-RAs over dexamethasone in all other antiemetic efficacy variables (early and delayed). Heterogeneity was found to be low in all of the comparisons. Linear-positive dose-response curve for dexamethasone 24-h vomiting and nausea incidence was seen (correlation coefficient being 0.21 and 0.28, respectively). Dexamethasone reduced the analgesic need (MH-odds of 0.64 (95% CI being 0.44 to 0.93) P = 0.02, I2 = 0)). Possibility of publication bias could not be ruled out (Egger's test, X-intercept = 1.41, P = 0.04). CONCLUSIONS: Dexamethasone demonstrates equal antiemetic efficacy compared to 5-HT3 receptor antagonists. The agents perform equally well both in early postoperative phase and up to 24 h after surgery. Use of dexamethasone replacing 5-HT3 RAs offers an additional advantage of lowering the opioid requirements during the perioperative period.

Role of Periarticular Liposomal Bupivacaine Infiltration in Patients Undergoing Total Knee Arthroplasty-A Meta-analysis of Comparative Trials.

BACKGROUND: Over last 2 years, many trials have evaluated newly approved liposomal bupivacaine for periarticular infiltration in total knee arthroplasty (TKA) with mixed results. Our meta-analysis attempts to consolidate the results and make evidence-based conclusions. METHODS: Trails comparing periarticular infiltration of liposomal bupivacaine to conventional analgesic regimens for total knee arthroplasty published till June 2016 were searched in medical database. Comparisons were made for length of stay (LOS), postoperative pain scores, range of motion, and opioid consumption. Meta-regression was performed for LOS to evaluate various analgesic control subgroups. RESULTS: Sixteen trials were included in the final analysis. Liposomal bupivacaine group showed a shorter LOS (reported in 13 subgroups) than control group by 0.17 ± 0.04 days (random effects, P < .001, I2 = 84.66%). Meta-regression for various types of control showed a predictability (R2) of 73%, τ2 = 0.013 (random effects, P < .001, I2 = 45.16). Only femoral block subgroup attained statistically significant shorter LOS on splitting the control group. Numeric pain scores were lower for pooled control group and local anesthetic infiltration subgroup in immediate postoperative phase. Second postoperative day analgesia was statistically superior to overall clubbed controls and femoral block subgroup. Superiority and/or inferiority of liposomal bupivacaine could not be proven for opioid consumption and range of motion because of a small pooled sample size. Publication bias is likely for LOS (Egger test, X intercept = 2.42, P < .001). CONCLUSION: Liposomal bupivacaine infiltration has questionable clinical advantage, as it marginally shortens patient's hospital stay especially in comparison with patients receiving analgesic femoral nerve block. Compared with conventional regimens, it can provide slightly superior yet sustained (till second postoperative day) perioperative analgesia. High heterogeneity suggests need for standardization of infiltration techniques for better predictability of results.

Effect of Qmix and Other Irrigants on Dentin Adhesives in Pulp Chambers of Primary Teeth: SEM Study.

OBJECTIVE: To compare the effect of different endodontic irrigants on microleakage of adhesives used within pulp chamber of primary molars. STUDY DESIGN: 72 Primary molars were divided into 6 groups, according to 3 irrigants and 2 adhesives used. After de-roofing the pulp chamber, pulp was extirpated. In 36 samples, pulp chambers were bonded with Xeno V+ after irrigation with either QMix (Group1); 17%EDTA+5%NaOCl (Group2) or normal saline (Group3) and in other half samples, pulp chambers were bonded with SinglebondUniversal after irrigation with either QMix (Group 4); 17%EDTA+5% NaOCl (Group5) or normal saline (Group 6). All the samples were restored with Filtek Z350. Ten teeth from each group were assessed for dye penetration. Two samples in each group were viewed under scanning electron microscope. Data was statistically analyzed using Mann-Whitney and Kruskal Wallis tests at a significance level of P < 0.05. RESULTS: Mean microleakage scores were: Group 1-1.5±0.70, Group 2-1.6±.51, Group 3-2.4±0.96, Group 4-1.2±0.42, Group 5-1.2±0.42, Group 6-1.1±0.32. CONCLUSIONS: Irrigation with QMix significantly reduced the microleakage of XenoV+ but had no significant effect on microleakage of SinglebondUniversal. Irrigation with EDTA/NaOCl or QMix had no detrimental effect on the sealing ability of either of the adhesive tested.

The impact on hospital resource utilisation of treatment of hepatic encephalopathy with rifaximin-α.

BACKGROUND & AIMS: Rifaximin-α reduces the risk of recurrence of overt hepatic encephalopathy. However, there remain concerns regarding the financial cost of the drug. We aimed to study the impact of treatment with rifaximin-α on healthcare resource utilisation using data from seven UK liver treatment centres. METHODS: All seven centres agreed a standardised data set and data characterising clinical, demographic and emergency hospital admissions were collected retrospectively for the time periods 3, 6 and 12 months before and following initiation of rifaximin-α. Admission rates and hospital length of stay before and during therapy were compared. Costs of admissions and drug acquisition were estimated using published sources. Multivariate analyses were carried out to assess the relative impact of various factors on hospital length of stay. RESULTS: Data were available from 326 patients. Following the commencement of rifaximin, the total hospital length of stay reduced by an estimated 31-53%, equating to a reduction in inpatient costs of between £4858 and £6607 per year. Taking into account drug costs of £3379 for 1-year treatment with rifaximin-α, there was an estimated annual mean saving of £1480-£3228 per patient. CONCLUSIONS: Initiation of treatment with rifaximin-α was associated with a marked reduction in the number of hospital admissions and hospital length of stay. These data suggest that treatment of patients with rifaximin-α for hepatic encephalopathy was generally cost saving.

Optimizing Prophylactic CPAP in Patients Without Obstructive Sleep Apnoea for High-Risk Abdominal Surgeries: A Meta-regression Analysis.

INTRODUCTION: Prophylactic continuous positive airway pressure (CPAP) can prevent pulmonary adverse events following upper abdominal surgeries. The present meta-regression evaluates and quantifies the effect of degree/duration of (CPAP) on the incidence of postoperative pulmonary events. METHODS: Medical databases were searched for randomized controlled trials involving adult patients, comparing the outcome in those receiving prophylactic postoperative CPAP versus no CPAP, undergoing high-risk abdominal surgeries. Our meta-analysis evaluated the relationship between the postoperative pulmonary complications and the use of CPAP. Furthermore, meta-regression was used to quantify the effect of cumulative duration and degree of CPAP on the measured outcomes. RESULTS: Seventy-three potentially relevant studies were identified, of which 11 had appropriate data, allowing us to compare a total of 362 and 363 patients in CPAP and control groups, respectively. Qualitatively, Odds ratio for CPAP showed protective effect for pneumonia [0.39 (0.19-0.78)], atelectasis [0.51 (0.32-0.80)] and pulmonary complications [0.37 (0.24-0.56)] with zero heterogeneity. For prevention of pulmonary complications, odds ratio was better for continuous than intermittent CPAP. Meta-regression demonstrated a positive correlation between the degree of CPAP and the incidence of pneumonia with a regression coefficient of +0.61 (95 % CI 0.02-1.21, P = 0.048, τ (2) = 0.078, r (2) = 7.87 %). Overall, adverse effects were similar with or without the use of CPAP. CONCLUSIONS: Prophylactic postoperative use of continuous CPAP significantly reduces the incidence of postoperative pneumonia, atelectasis and pulmonary complications in patients undergoing high-risk abdominal surgeries. Quantitatively, increasing the CPAP levels does not necessarily enhance the protective effect against pneumonia. Instead, protective effect diminishes with increasing degree of CPAP.

Aprepitant for postoperative nausea and vomiting: a systematic review and meta-analysis.

Postoperative nausea and vomiting (PONV) is an important clinical problem. Aprepitant is a relatively new agent for this condition which may be superior to other treatment. A systematic review was performed after searching a number of medical databases for controlled trials comparing aprepitant with conventional antiemetics published up to 25 April 2015 using the following keywords: 'Aprepitant for PONV', 'Aprepitant versus 5-HT3 antagonists' and 'NK-1 versus 5-HT3 for PONV'. The primary outcome for the pooled analysis was efficacy of aprepitant in preventing vomiting on postoperative day (POD) 1 and 2. 172 potentially relevant papers were identified of which 23 had suitable data. For the primary outcome, 14 papers had relevant data. On POD1, 227/2341 patients (9.7%) patients randomised to aprepitant had a vomiting episode compared with 496/2267 (21.9%) controls. On POD2, the rate of vomiting among patients receiving aprepitant was 6.8% compared with 12.8% for controls. The OR for vomiting compared with controls was 0.48 (95% CI 0.34 to 0.67) on POD1 and 0.54 (95% CI 0.40 to 0.72) on POD2. Aprepitant also demonstrated a better profile with a lower need for rescue antiemetic and a higher complete response. Efficacy for vomiting prevention was demonstrated for 40 mg, 80 mg and 125 mg without major adverse effects. For vomiting comparison there was significant unexplainable heterogeneity (67.9% and 71.5% for POD1 and POD2, respectively). We conclude that (1) aprepitant reduces the incidence of vomiting on both POD1 and POD2, but there is an unexplained heterogeneity which lowers the strength of the evidence; (2) complete freedom from PONV on POD1 is highest for aprepitant with minimum need for rescue; and (3) oral aprepitant (80 mg) provides an effective and safe sustained antivomiting effect.

Endodontic Management of Maxillary First Molar with Five Root Canals, Including Two Distobuccal Root Canals: A Case Report.

Multiple canals in the root are part of the normal morphology of the tooth. A canal may sometimes be overlooked, however, and this may lead to failure of treatment. The first step in successful endodontic treatment, therefore, is gaining access to the pulp chamber and locating all the canals. In order to achieve this goal, practitioners need to be familiar with all possible variations in root canal morphology, and should thoroughly explore roots to ensure that all canals are identified, debrided, and obturated. Here, we report the diagnosis, treatment planning, and endodontic management of a maxillary first molar with five root canals, including two distobuccal root canals, in a 22-year-old woman.

Epidural chloroprocaine bolus in emergency cesarean section-lessons learned from a near mishap.

Administration of a large bolus of epidural chloroprocaine to hasten the spread of anesthesia is an accepted practice during emergency cesarean section. Occasionally, this practice can result in a very high block that can compromise patient's safety. We describe a case of epidural chloroprocaine administration in a 4 point position resulting in a high dermatomal block requiring respiratory assistance. Events surrounding the case are discussed, with a view to warn the reader about the pitfalls of such a practice.

The association of gender and body mass index with postoperative pain scores when undergoing ankle fracture surgery.

BACKGROUND: Intraoperative administration of opiates for postoperative analgesia requires a dosing strategy without clear indicators of pain in an anesthetized patient. Preoperative patient characteristics such as body mass index (BMI), gender, age, and other patient characteristics may provide important information regarding opiate requirements. This study intends to determine if there is an association between gender or BMI and the immediate postoperative pain scores after undergoing an open reduction and internal fixation (ORIF) of an ankle fracture with general anesthesia and morphine only analgesia. MATERIALS AND METHODS: Using a retrospective cohort design, the perioperative records were reviewed at a university healthcare hospital. One hundred and thirty-seven cases met all inclusion and no exclusion criteria. Postanesthesia care unit (PACU) records were reviewed for pain scores at first report and 30 min later as well as PACU opiate requirements. T-test, chi-square, and Mann-Whitney tests compared univariate data and multivariate analysis was performed by linear regression. RESULTS: There were no statistically significant PACU pain score group differences based on gender or BMI. Post hoc analysis revealed that in the setting of similar pain scores, obese patients received a similar weight based intraoperative morphine dose when using adjusted body weight (ABW) compared to nonobese subjects. A further finding revealed a negative correlation between age and pain score (P = 0.001). CONCLUSION: This study did not find an association between obesity or gender and postoperative pain when receiving morphine only preemptive analgesia. This study does support the use of ABW as a means to calculate morphine dosing for obese patients and that age is associated with lower immediate pain scores.

Antioxidants: The new frontier for translational research in cerebroprotection.

It is important for the anesthesiologist to understand the etiology of free radical damage and how free-radical scavengers attenuate this, so that this knowledge can be applied to diverse neuro-pathological conditions. This review will concentrate on the role of reactive species of oxygen in the pathophysiology of organ dysfunction, specifically sub arachnoid hemorrhage (SAH), traumatic brain injury (TBI) as well as global central nervous system (CNS) hypoxic, ischemic and reperfusion states. We enumerate potential therapeutic modalities that are been currently investigated and of interest for future trials. Antioxidants are perhaps the next frontier of translational research, especially in neuro-anesthesiology.