Raha Abdul Rahman

Antibacterial performance of Ag nanoparticles and AgGO nanocomposites prepared via rapid microwave-assisted synthesis method

Silver nanoparticles and silver-graphene oxide nanocomposites were fabricated using a rapid and green microwave irradiation synthesis method. Silver nanoparticles with narrow size distribution were formed under microwave irradiation for both samples. The silver nanoparticles were distributed randomly on the surface of graphene oxide. The Fourier transform infrared and thermogravimetry analysis results showed that the graphene oxide for the AgNP-graphene oxide (AgGO) sample was partially reduced during the in situ synthesis of silver nanoparticles. Both silver nanoparticles and AgGO nanocomposites exhibited stronger antibacterial properties against Gram-negative bacteria (Salmonella typhi and Escherichia coli) than against Gram-positive bacteria (Staphyloccocus aureus and Staphyloccocus epidermidis). The AgGO nanocomposites consisting of approximately 40 wt.% silver can achieve antibacterial performance comparable to that of neat silver nanoparticles.

Comparing the effectiveness of ropivacaine 0.5% versus ropivacaine 0.2% for transabdominis plane block in providing postoperative analgesia after appendectomy

OBJECTIVE The basis for the transversus abdominis plane (TAP) block involves infiltration of a local anesthetic into the neurofascial plane between the internal oblique and the transversus abdominis muscles, causing a regional block that spreads between the L1 and T10 dermatomes. Thus, the TAP block is said to be suitable for lower abdominal surgery. This study was designed to compare the analgesic efficacy of two different concentrations of ropivacaine for TAP block in patients undergoing appendectomy. METHODS Fifty-six patients with American Society of Anesthesiologists physical status I or II, aged 18 years and above, undergoing appendectomy were recruited in this prospective, randomized, double-blind study. They were divided into two groups: Group A patients who received 0.5 mL/kg of ropivacaine 0.5% and Group B patients who received 0.5 mL/kg of ropivacaine 0.2% via TAP block under ultrasound guidance. Postoperative pain was assessed using the visual analog scale upon arrival at the recovery room in the operating theatre, just prior to being discharged to the ward, and at 6 hours, 12 hours, 18 hours, and 24 hours postoperatively to compare the effectiveness of analgesia. RESULTS Intraoperatively, patients in Group B required a significantly greater amount of additional intravenous fentanyl than those in Group A. There were no significant statistical differences in pain scores at rest and on movement at all assessment times as well as in the dose of 24-hour intravenous morphine consumption given via patient-controlled analgesia postoperatively between the two groups. CONCLUSION The effectiveness of two different concentrations of ropivacaine (0.5% versus 0.2%) given via TAP block was comparable in providing postoperative analgesia for patients undergoing appendectomy.

Effectiveness of P6 acupoint electrical stimulation in preventing postoperativenausea and vomiting following laparoscopic surgery.

BACKGROUND/AIM The effects of pericardium 6 (P6) electrical stimulation in patients at risk of postoperative nausea and vomiting (PONV) following laparoscopic surgery were evaluated. MATERIALS AND METHODS Eighty patients for laparoscopic surgery with at least one of the determined risks (nonsmoker, female, previous PONV/motion sickness, or postoperative opioid use) were randomized into either an active or sham group. At the end of surgery, Reletex electrical acustimulation was placed at the P6 acupoint. The active group had grade 3 strength and the sham group had inactivated electrodes covered by silicone. It was worn for 24 h following surgery. PONV scores were recorded. RESULTS The active group had significantly shorter durations of surgery and lower PONV incidence over 24 h (35.1% versus 64.9%, P = 0.024) and this was attributed to the lower incidence of nausea (31.4% versus 68.6%, P = 0.006). The overall incidence of vomiting was not significantly different between the groups, but it was higher in the sham group of patients with PONV risk score 3 (23.9%, P = 0.049). CONCLUSION In patients at high risk for PONV, P6 acupoint electrical stimulation lowers the PONV incidence by reducing the nausea component. However, this reduction in nausea is not related to increasing PONV risk scores.