Neutral pH Fenton and photo-Fenton activity of Mo-doped iron-pyrite particles.

Low H2O2 utilization efficiency for hydroxyl radical generation, acidic pH, and recyclability are critical limitations of heterogeneous Fenton and photo-Fenton catalysts. The present research shows that the optimum Mo doping of FeS2 particles can largely alleviate these catalysis constraints. A solvothermal protocol was followed to prepare polyvinyl pyrrolidone (PVP) stabilized FeS2 and Mo-doped FeS2 particles. XRD observations showed that Mo doping increases the lattice parameters of FeS2. The band gap of the Mo-doped FeS2 particles decreased to 1.58 eV from the 2.24 eV value exhibited by pure FeS2 particles. Structural and electronic structure DFT calculations support these results. The Fenton and photo-Fenton p-nitrophenol (PNP) degradation at neutral pH on PVP-stabilized Mo-doped FeS2 and FeS2 particles were examined. The photo-Fenton results were substantially better than under Fenton conditions. The best PNP degradation photo-Fenton turnover frequency (TOF) recorded was 254.50 µmol g-1 min-1 on the PVP stabilized 4% Mo-doped FeS2 sample. The Mo-doped FeS2 catalysts were stable under photo-Fenton recycling, and the H2O2 (1.66 mM) required for these reactions was significantly lower than most reports (30-6000 mM). Given the economic importance of the latter in Fenton/photo-Fenton reactions, H2O2 normalized turnover frequency (13.85 and 153.31 mg-1 min-1 L for Fenton and photo-Fenton) values were used to evaluate catalytic activities.

Does Time of Administration of Intravenous Ketorolac Impact Pain-Related Outcomes in Dacryocystorhinostomy?

PURPOSE: An emerging body of evidence indicates that intravenous ketorolac (IVK) reduces pain scores and the requirement for opioid analgesics in a variety of oculofacial procedures. This study was performed to assess the impact of timing of IVK administration on these benefits after external dacryocystorhinostomy (DCR). METHODS: Patients were randomized to receive IVK before (n = 50), during (n = 50), or after DCR (n = 50). An additional cohort of control patients did not receive the medication (n = 50). Postoperative pain was measured via a visual analog scale immediately after DCR on the first day after surgery (POD1). Additionally, the need for opioid analgesics to control pain was recorded. Statistical analyses were performed via a dedicated computerized software package. RESULTS: Immediately after surgery, mean pain scores were 5.26 for control patients, and 2.30, 2.44, and 2.36 for patients that received IVK pre-, intra-, and post-operatively, respectively (p < .001 for each condition, as compared to controls). On POD1, mean pain scores were 3.52 for control patients and 1.38, 1.32, and 1.28 for patients that received IVK pre-, intra-, and post-operatively, respectively (p < .001 for each condition, as compared to controls). 28% of control patients required postoperative opioid analgesics, as compared to 6%, 4%, and 4% among patients that received IVK pre-, intra-, and postoperatively, respectively (p < .05 for each condition, as compared to controls). CONCLUSIONS: IVK significantly reduces postoperative pain and the requirement for opioid analgesics after DCR, regardless of the timing of administration. This benefit appears to extend into the first postoperative day.

Intravenous Ketorolac Reduces Pain Score and Opioid Requirement in Orbital Surgery.

PURPOSE: Intravenous ketorolac (IVK) is an effective agent to reduce postoperative pain without the risks inherent to opioid analgesics. However, many clinicians avoid using this agent due to concerns regarding hemorrhagic complications. This study was performed to assess the efficacy and safety of IVK in the setting of orbital surgery. METHODS: In a single dose prospective study, patients either received IVK immediately before orbital surgery (n = 50) or acted as controls (n = 50). Postoperative pain was evaluated via a numerical scale (range = 0-10) immediately after surgery, before discharge to home, and on the first postoperative day (POD1). The requirements for opioid analgesic and anti-emetic medications were determined by the nursing staff and recorded. Statistical analyses were performed via a dedicated software package. RESULTS: Fifty patients received IVK (24 males, 26 females, mean age = 54 years, SD = 18 years) and 50 patients acted as controls (26 males, 24 females, mean age = 50 years, SD = 19 years) immediately before orbital surgery. Mean pain scores were lower in patients who received IVK than in controls immediately after surgery (3.08 vs. 5.44, p = 0.0001) and on POD1 (1.04 vs. 2.66, respectively, p = 0.0001). Four patients (8%) who received IVK and 12 patients who did not (24%) required opioid analgesics to control pain (p = 0.03). No patient experienced a hemorrhagic complication or required an emergent return to the operating room. CONCLUSIONS: In the setting of orbital surgery, IVK safely and effectively reduces pain and the requirement for opioid analgesics. Within the limits of the study size, increased risks of bleeding-related complications were not identified.

Preoperative Intravenous Ketorolac Safely Reduces Postoperative Pain in Levator Advancement Surgery.

PURPOSE: To assess the impact of intravenous ketorolac (IVK) on self-reported pain scores, requirements for opioid analgesic and anti-emetic medications, and bleeding complications in the setting of levator advancement surgery METHODS:: A prospective randomized controlled trial was performed among adult patients undergoing levator advancement surgery. Pain scores were measured immediately after surgery, prior to discharge from the surgical facility, and on the first postoperative day. The requirements for postoperative analgesic and anti-emetic medications were recorded. Statistical comparisons were performed via a dedicated computerized software package. RESULTS: Fifty patients (20 males, 30 females, mean age = 65.7 years, standard deviation = 11.9 years) underwent levator advancement without IVK and acted as controls. An additional 50 patients received IVK (19 males, 31 females, mean age = 64.6 years, standard deviation = 12.0 years). As compared with control patients, IVK resulted in statistically significant reductions in pain score immediately after surgery (4.62 vs. 1.44, p = 0.0001) and on postoperative day 1 (3.22 vs. 1.24, p = 0.0001). Fourteen patients (28%) in the control and 4 patients (8%) in the group that received IVK required opioid analgesics (p = 0.017). Seven patients (14%) in the control group and 1 patient in the group that received IVK required anti-emetic medications (p = 0.059). No patient experienced a hemorrhagic complication. CONCLUSIONS: In the setting of levator advancement surgery, IVK results in a dramatic reduction in self-reported pain score immediately after surgery and on postoperative day 1 and the requirement for opioid analgesics. This medication may be safely utilized for ptosis repair.

Intravenous Acetaminophen in Orbital Surgery.

PURPOSE: To assess the role of intravenous acetaminophen (IVA) in orbital surgery. METHODS: Fifty control patients underwent orbital surgery without IVA. Fifty patients received 1 g of IVA within 30 minutes of surgery, and 50 patients received 1 g of IVA immediately preoperatively. Postoperative requirements for analgesic and anti-emetic medications and standardized pain scores were recorded. RESULTS: 44 patients (88%) in the control group and 57 patients (57%) that received IVA preoperatively required analgesic medications (p = 0.0023). 31 patients (62%) that received the medication within 30 minutes of surgery and 26 patients (52%) that received IVA immediately preoperatively required analgesic medications (p = 0.77). The control group had a greater requirement for analgesic medications than patients that received IVA within 30 minutes of orbital surgery (p = 0.0076) and those that received IVA immediately preoperatively (p = 0.032). Twelve patients in the control group (24%) and 4 patients (4%) in the group that received IVA preoperatively received anti-emetic medications (p = 0.0078). Mean pain scores for all patients that received IVA, patients that received IVA within 30 minutes of surgery, and patients that received IVA at the time of surgery were 3.68 (standard deviation = 3.24), 3.12 (standard deviation = 3.05) and 4.39 (standard deviation = 3.37), respectively, as compared to a mean control group score of 7.92 (standard deviation = 3.36), (p = 8.30x10). CONCLUSIONS: When administered prior to orbital surgery, IVA significantly reduced pain scores and postoperative requirements for analgesic and anti-nausea medications.