Background: Maintaining hemodynamic stability during intracranial surgery is one of the most important tasks. There is no general agreement regarding which anesthetics are optimal for craniotomy. Propofol and short-acting opioids are usually used, but their use is not without side effects. Recently, dexmedetomidine has been considered a safe alternative in different surgeries. Objectives: We aimed to assess the efficacy of 0.5 µg/kg/h dexmedetomidine infusion without loading dose as an adjunct to general anesthesia for craniotomy. Methods: A prospective, randomized, double-blinded, parallel-group, placebo-controlled trial was conducted. Setting: Single university teaching hospital’s operating rooms and postoperative intensive care unit. Patients: A total of 50 patients scheduled for elective supratentorial craniotomy participated in this study. Interventions: Patients were randomly divided into either control group (Group C) and Dexmedetomidine group (Group D). Main outcome measure: Intraoperative hemodynamics measurements at specific timings. Results: We found that dexmedetomidine had significantly maintained mean arterial blood pressure and heart rate (P-value < 0.001); with lower intraoperative fentanyl and propofol consumption in group D (132 ± 35 µg and 14 ± 30 mg, respectively) when compared to group C (260 ± 38 µg and 534 ± 66 mg, respectively). Finally, a lesser sedation level was noticed in the dexmedetomidine group, together with a significantly lesser recovery time of 10.3 ± 4 min. Conclusions: Dexmedetomidine infusion without loading dose could be an efficacious and safe agent in achieving hemodynamic stability with intraoperative opioid-sparing effect and lesser recovery time.

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The catalytic conversion of waste cooking oil (WCO) was carried out over a synthetic nano catalyst of cobalt aluminate (CoAl2O4) to produce biofuel range fractions. A precipitation method was used to create a nanoparticle catalyst, which was then examined using field-emission scanning electron microscopy, X-ray diffraction, energy dispersive X-ray, nitrogen adsorption measurements, high-resolution transmission electron Microscopy (HRTEM), infrared spectroscopy, while a gas chromatography-mass spectrometer (GC–MS) was used to analyze the chemical construction of the liquid biofuel. A range of experimental temperatures was looked at including 350, 375, 400, 425, and 450 °C; hydrogen pressure of 50, 2.5, and 5.0 MPa; and liquid hour space velocity (LHSV) of 1, 2.5, and 5 h−1. As temperature, pressure, and liquid hourly space velocity increased, the amount of bio-jet and biodiesel fractional products decreased, while liquid light fraction hydrocarbons increased. 93% optimum conversion of waste cooking oil over CoAl2O4 nano-particles was achieved at 400 °C, 50 bar, and 1 h−1 (LHSV) as 20% yield of bio-jet range,16% gasoline, and 53% biodiesel. According to the product analysis, catalytic hydrocracking of WCO resulted in fuels with chemical and physical characteristics that were on par with those required for fuels derived from petroleum. The study's findings demonstrated the nano cobalt aluminate catalyst's high performance in a catalytic cracking process, which resulted in a WCO to biofuel conversion ratio that was greater than 90%. In this study, we looked at cobalt aluminate nanoparticles as a less complex and expensive alternative to traditional zeolite catalysts for the catalytic cracking process used to produce biofuel and thus can be manufactured locally, which saves the cost of imports for us as a developing country.

The current work investigated the preparation of Nano-particles of Co/Zn Al2O4 as a catalyst via co-precipitation method. Several analyses, including BET, XRD, HRTEM, EDX, SEM, and FTIR, were used to characterize it. The analysis revealed that the prepared catalyst had an average surface area of 69.20 m2/g, a cross-sectional area of 16.2 m2/molecule, an average particle size of approximately 28 nm, and a pore size of 0.22 cm3/g. The prepared catalyst was used in a bio fuel synthesis process via thermo-catalytic cracking of waste cooking oil (WCO) in a single step batch reactor. Catalyst loading was tested with different weight percentage of 1.5%, 2%, and 2.5%. The pilot study revealed that the best conditions for optimizing bio jet fuel yield were 400 °C, a catalyst loading of 2%, and a reaction time of 30 min.The optimal cut-off from the distillation process of crude liquid bio fuel product which represents a fraction of bio-jet fuel was in the range from 150 to 240 °C.

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Background hip replacement surgery is common among elderly patients. These patients have increased risk for perioperative mortality and morbidity due to additional comorbidities, such as cardiac, endocrine, renal, cerebral and respiratory diseases. Aim of the Work to compare between continuous spinal anesthesia and combined spinal epidural anesthesia in patients scheduled for elective major hip surgeries as regards their effectiveness and possible complications during operation. Patients and Methods after obtaining the approval of the ethical committee of faculty of medicine, Ain-Shams University, and patients’ written informed consents, this prospective randomized clinical trial study was conducted at Ain Shams University Hospitals at the orthopedics operating theatre. Seventy two patients aged older than 30 years, of both sexes and American Society of Anesthesiologists (ASA) class I, II, scheduled for elective major hip surgeries like total hip replacement or hemi arthroplasty were included in the study. All Patients were assigned randomly by using a computer generated program with closed envelops to one of the two equal groups:CSAgroup(36)patient and CSEgroup(36)patient. Results there was no statistically significant differences between the CSA and CSE groups as regards demographic data; Age, Sex or BMI. Baseline HR was similar in both groups. The heart rate was significantly higher in the CSE group at 5 min and 15 min when compared to CSA group. The mean blood pressure was significantly lower in group CSE at 5min anf 15 min when compared to CSA group.The total dose of bupivacaine 0.5% mg collectively given was much lower in the CSA group than the CSE group. The onset of sensory block (time between the end of injection and the time to reach T10sesnsory level) and degree of motor block between two groups showed no statistically significant difference but the level of sensory block was significantly higher in CSE group than CSA group.there was no significant difference as regard PDPH, Post operative nausea and vomiting, Bradycardia but there was significant difference as regard incidence of hypotension being higher in CSE group than CSA group. The time of first analgesic request showed no significant difference between the two groups Conclusion both continuous spinal anesthesia and compined spinal epidural anesthesia are safe anesthetic techniques for lower limb surgeries. CSA offers possibilities of more hemodynamic stability with smaller doses of local anesthetics than CSE with rapid onset of sensory block and good extendede post operative analgesia.