Randomized Controlled Trial Comparing the Effects of Preoperative Carbohydrate and Non-carbohydrate Loading on Gastric Emptying in Diabetic and Non-diabetic Patients Posted for Elective Surgery.

Background Preoperative fasting for six hours and accepting clear fluids till two hours of surgery is followed as a regular practice. Carbohydrate-rich fluids antagonize catabolism and are claimed to be tolerated better. This study aims to compare the effect of carbohydrate-rich drinks on gastric volume and blood sugar control in diabetic and non-diabetic patients undergoing elective surgery with plain water. Methods Two hundred forty patients aged 40 to 65 undergoing elective surgery under regional anesthesia were randomized into diabetic control, diabetic study, non-diabetic control, and non-diabetic study. Control groups were given 400 ml of plain water, while the study group received 50 grams of dextrose dissolved in 400 ml of water two hours prior to surgery. Gastric volume was evaluated using USG, and thirst and discomfort were assessed using the Likert scale. Perioperatively, blood sugar values were monitored and kept under control using insulin. Results Mean gastric volume (ml) in diabetic control (35.3±12.95 ml), diabetic study (31.2±11.75 ml), non-diabetic control (29±11.42 ml), and non-diabetic study (30.4±9.12 ml) showed no statistically significant difference (p>0.05). Capillary blood glucose (CBG) values two hours post fluid intake showed a significant increase in CBG levels in the diabetic study (183.2±28.67 mg/dl) compared to the diabetic control group (138.66±15.81 mg/dl). The values returned to baseline within six hours. Thirst and discomfort were significantly lower in the study group of diabetic and non-diabetic populations. Conclusion We conclude that carbohydrate loading does not affect gastric volume in diabetics and non-diabetics. However, the sugar values do increase which may warrant hourly checking and administration of insulin in diabetics.

A Randomized Control Trial to Compare Hemodynamic Parameters of Patients Undergoing Percutaneous Nephrolithotomy Under Combined Spinal-Epidural and General Anesthesia in a Tertiary Hospital.

Background and Aim: Percutaneous nephrolithotomy (PCNL) under epidural anesthesia has been reported to have few advantages over general anesthesia, like lower postoperative pain and less need for analgesics. There are limited studies on PCNL being performed under neuraxial anesthesia in supine position. Hence the present study was conceived to compare hemodynamic parameters in patients undergoing percutaneous nephrolithotomy (PCNL) in the supine position under combined spinal-epidural with general anesthesia (GA). Material and Methods: A prospective, randomized control trial was conducted among 90 patients who were posted to undergo elective percutaneous nephrolithotomy in the the supine position, after obtaining Institutional Ethical Committee (IEC) approval and CTRI (Clinical Trial Registry - India) registration. Patients were randomly allotted to undergo surgery either under general anesthesia (group GA) or combined spinal epidural anesthesia (group CSE) by computer-generated random number method. Hemodynamic parameters, postoperative analgesic requirement and incidence of blood transfusion were recorded and analyzed. Results: There was no significant difference between the two groups with respect to gender, ASA grade, surgery duration, calculus size and pulse rate. There was a statistically significant reduction in mean arterial pressure from 5 to 50 minutes of surgery and less incidence of blood transfusion in patients in the CSE group. Patients who underwent PCNL in the supine position under CSE required lesser analgesics postoperatively compared to those under general anesthesia. Conclusion: Combined spinal epidural analgesia can be used as an alternative to general anesthesia for patients undergoing PCNL in the supine position in view of less MAP and reduced postoperative analgesic and blood transfusion requirement.

A Randomized Controlled Trial Comparing the Effect of Phenylephrine by Intramuscular Route With Intravenous Infusion in Maintaining Haemodynamic Stability During Elective Lower Segment Caesarean Section Under Spinal Anaesthesia.

Background Hypotension is a commonly encountered side effect in patients undergoing spinal anaesthesia, particularly in patients undergoing caesarean section. Phenylephrine is a widely used drug to treat spinal-induced hypotension and to maintain hemodynamic stability. Our aim is to evaluate the effectiveness of phenylephrine given through two different routes prophylactically in prevention of post-spinal hypotension in patients undergoing caesarean section. Methods A total of 150 healthy pregnant women undergoing elective caesarean section were randomly allocated into three groups: Group M (prophylactic intramuscular use of 2 mg phenylephrine), group V (prophylactic intravenous infusion of 30 mcg phenylephrine per minute), and group P (no prophylaxis), rescue phenylephrine 30 mcg IV and atropine 0.6 mg IV were used intraoperatively to treat bradycardia and hypotension in all three groups. The primary outcome was maternal hemodynamic changes. Results There was an insignificant difference in demographic data between the groups. Maternal systolic and diastolic blood pressure were more stable in group M compared to group V and group P. Heart rate was significantly lower only in group V. We did not observe any statistical difference between the groups in the APGAR score or the fetal arterial blood gas values. The incidence of nausea and vomiting was more in group P. Conclusion Preventive intramuscular phenylephrine exhibited a more stable maternal hemodynamics when compared with the prophylactic intravenous infusion of phenylephrine and placebo in elective caesarean under spinal anaesthesia.

Intrinsically strained noble metal-free oxynitrides for solar photoreduction of CO2.

Metal oxynitrides show promising activity for photocatalytic solar water splitting and CO2 reduction under solar irradiance. Precise control of cation ratios in oxynitrides is an inevitable challenge that needs to be overcome for achieving effective band gap tuning. Here we report the density functional theory-based calculations for the intricate structure-function relationships of Zn-Ga based oxynitrides and correlate the results with the experimental parameters. Crucial material property descriptors such as elemental composition, intrinsic lattice strain, and vacancy defects were exploited during the synthesis to achieve stable oxynitride photocatalysts that demonstrated CO2 conversion to CO under simulated solar light, without any noble metal impregnation. The highest CO production rate surpassed that of TiO2 under the same conditions. This work inspires future research on oxynitride materials with tailored optical properties and sustainable photocatalytic activity which enables their large scale applications.

Covalent Organic Framework Decorated with Vanadium as a New Platform for Prins Reaction and Sulfide Oxidation.

Chemical functionalization or docking of transition-metal ions in covalent organic frameworks (COFs) is of importance for calibrating properties and widening potential applications. In this work, we demonstrate the successful decoration of COF with vanadium as exemplified in the context of post-synthetically modifying two-dimensional COF that features eclipsed stacking structure, large pores, hydroxyl functionalities, high thermal and chemical stability using vanadyl acetylacetonate. The potent catalytic behavior of vanadium-decorated COF was systematically investigated in the reactions of Prins condensation and sulfide oxidation, which revealed its excellent catalytic performances in terms of efficacious activity, preservation of framework crystallinity and reusability. Our work not only contributes the first ever report of vanadium-decorated COF-catalyzed Prins reaction and sulfide oxidation but paves a new way for docking COF with metals for a broad range of applications.

Facile Aqueous-Phase Synthesis of the PtAu/Bi2O3 Hybrid Catalyst for Efficient Electro-Oxidation of Ethanol.

In this work, we present a facile aqueous-phase synthesis of a hybrid catalyst consisting of PtAu alloy supported on Bi2O3 microspheres. Multistep reduction of HAuCl4 and K2PtCl4 salts on Bi2O3 and subsequent annealing lead to the formation of this hybrid catalyst. To the best of our knowledge, this is the first report of using Bi2O3 as a catalyst support in fuel cell applications. The material was characterized by powder X-ray diffraction and various microscopic techniques. This composite showed remarkable activity as well as stability toward the electro-oxidation of ethanol in comparison to commercially available Pt/C. The order of the reactivity was found to be commercial Pt/C (50.4 mA/m2mgPt-1) < Pt/Bi2O3(10) (108 mA/m2mgPt-1) < PtAu/Bi2O3(10) (459 mA/m2mgPt-1). The enhancement in the activity can be explained through cooperative effects, namely, ligand effects of gold and Bi2O3 support, which helps in removing carbon monoxide molecules to avoid the poisoning of the Pt active sites.