Incidence of drug-related adverse events related to the use of high-alert drugs: A systematic review of randomized controlled trials

Background

High-alert medication (HAM) is more predictable to cause significant harm to the patient, even when used as intended. The damage related to the HAM lead not only suffering to the patient, but also raise the additional costs associated with care.

Objective

Evaluate the incidence of drug-related adverse events related to the use of high-alert medications.

Methods

It was conducted an active search for information through COCHRANE databases, LILACS, SciELO, SCOPUS, PubMed/MEDLINE and WEB OF SCIENCE. The search strategy included the following terms: "Patient safety", "Medication errors" and "Hospital" and "High Alert Medications" or "Dangerous Drugs" in different combinations. Then two reviewers independently conducted a preliminary evaluation of relevant titles, abstracts and finally full-text. Studies quality was evaluated according to PRISMA declaration.

Results

The systematic review evaluated seven articles, which showed that only 11 HAM identified in the literature could have serious events. The most frequently cited were warfarin (22.2%) which progressed from deep vein thrombosis to gangrene, suggesting lower initial doses, followed by cyclophosphamide (22.2%) and cyclosporine (22.2%) which presented invasive fungal infection and death. In addition to these, morphine was compared with its active metabolite (M6G), with M6G causing fewer serious clinical events related to nausea and vomiting, reducing the need for concomitant use of antiemetics.

Conclusions

The most reported drug classes in the articles included that were related to incidence of drug-related adverse events in use of high-alert medications: morphine, M6G-glucuronide, haloperidol, promethazine, ivabradine, digoxin, warfarin, ximelagatran, cyclophosphamide, cyclosporine, and ATG. The formulate protocols for the use of these medications, with importance placed on evaluating, among the classes, the medication that causes the least harm.

Effect of the photoinitiator system on the polymerization of secondary methacrylamides of systematically varied structure for dental adhesive applications

OBJECTIVE

The aim of this study was to investigate the influence of the photoinitiator system on the polymerization kinetics of methacrylamide-based monomers as alternatives to methacrylates in adhesives dental-based materials.

METHODS

In total, 16 groups were tested. Monofunctional monomers (2-hydroxyethyl methacrylate) - HEMA; (2-hydroxy-1-ethyl methacrylate) -2EMATE, (2-hydroxyethyl methacrylamide) - HEMAM; and (N-(1-hydroxybutan-2-yl) methacrylamide) -2EM; were combined with bifunctional monomers containing the same polymerizing moieties as the monofunctional counterparts (HEMA-BDI; 2EMATE-BDI; HEMAM-BDI; and 2EM-BDI) at 50/50 M ratios. BHT was used as inhibitor (0.1 wt%) and the photoinitiators used were: CQ + EDMAB (0.2/0.8), BAPO (0.2), IVOCERIN (0.2), and DMPA (0.2), in wt%. The polymerization kinetics were monitored using Near-IR spectroscopy (∼6165 cm-1) in real-time while the specimens were photoactivated with a mercury arc lamp (Acticure 2; 320-500 nm, 300 mW/cm2) for 5 min, and maximum rate of polymerization (Rpmax, in %.s-̄1), degree of conversion at Rpmax (DC@Rpmax, in %), and the final degree of conversion (Final DC, in %) were calculated (n = 3). Initial viscosity was measured with an oscillating rheometer (n = 3). Data were analyzed using Two-way ANOVA for the polymerization kinetics and one-way ANOVA for the viscosity. Multiple comparisons were made using the Tukey's test (∝ = 0.05).

RESULTS

There was statistically significant interaction between monomer and photoinitiator (p < 0.001). For the methacrylates groups, the highest Rpmax was observed for HEMA + DMPA and 2EMATE + BAPO. For methacrylamides groups, the highest Rpmax were observed for HEMAM and 2EM, both with DMPA. Final DC was higher for the methacrylate groups, in comparison with methacrylamide groups, independent of the photoinitiators. However, for the methacrylamide groups, the association with BAPO led to the lowest values of DC. In terms of DC@Rpmax, methacrylate-based systems showed significantly higher values than methacrylamide formulations. DMPA and Ivocerin led to higher values than CQ/EDMAB and BAPO in methacrylamide-based compounds. BAPO systems showed de lowest values for both HEMA and HEMAM formulations. For the viscosity (Pa.s), only 2EM had higher values (1.60 ± 0.15) in comparison with all monomers. In conclusion, polymerization kinetics was affected by the photoinitiators for both monomers. Viscosity was significantly increased with the use of secondary methacrylamide.

SIGNIFICANCE

this work demonstrated the feasibility of using newly-synthesized methacrylamide monomers in conjunction with a series of initiator systems already used in commercial materials.

Effect of the addition of thiourethane oligomers on the sol⿿gel composition of BisGMA/TEGDMA polymer networks

OBJECTIVES

Thiourethane oligomers have been shown to increase the fracture toughness and reduce the polymerization stress of methacrylate-based materials. However, network formation has not been elucidated in these materials yet. The aim of this study was to evaluate how the addition of a thiourethane oligomer (TU) influences the sol/gel composition and network structure of methacrylate-based materials using dynamic mechanical analysis and extraction methods.

MATERIALS AND METHODS

BisGMA/TEGDMA at systematically varied mass ratios (20/80 to 80/20wt%) were mixed with pre-polymerized thiourethane oligomers at 0 (control) or 20wt%, synthesized by combining pentaerythritol tetra-3-mercaptopropionate with dicyclohexylmethane 4,4⿲-Diisocyanate, at 1:2 isocyanate:thiol. 0.1wt% of 2,2-Dimethoxy-2-phenylacetophenone was added as the photoinitiator and 0.3wt% of 2,6-di-tert-butyl-4-methylphenol was added as a free radical inhibitor. Disk specimens (0.8ÿ10mm in diameter, n=3) were photoactivated at 270mW/ (320⿿500nm) for 1min. The degree of conversion (DC) was measured in near-IR (˿6165cm⿿1). Specimens were immersed in two different solvents (water for 7 days or dicholoromethane for 48h). Water sorption (WS) and solubility (SL) were obtained according to ISO 4049. The leachates for both solutions were analyzed with 1H-NMR (400MHz, CDCL3). Bar specimens (1ÿ3ÿ25mm, photocured and then post-processed at 180°C for 8h to DC>95%) were subjected to dynamic mechanical analysis (⿿30 to 230°C) to obtain glass transition temperature (Tg), tan delta curves and crosslinking density (ν). Data was analyzed with two-way ANOVA/Tukey⿿s test (95%).

RESULTS

In general, the presence of TU increased the overall conversion. The WS was similar for all groups, but the SL decreased by 2-fold with the addition of the TU oligomer for all compositions, except BisGMA/TEGDMA 80/20. The BisGMA concentration of the leachates increased with increasing BisGMA in the initial mixture, and with the presence of thiourethane. This compositional drift of the gel with the presence of TU was attributed to the preferential dissolution of TEGDMA into the TU network. Tg and ν decreased with the addition of TU, as expected. The addition of TU produced more homogeneous networks, as evidenced by narrower breadth of the tan delta curve.

CONCLUSION

The addition of TU affected the composition of the sol/gel in crosslinked networks, which were more homogeneous and presented 2-fold less potentially toxic leachates than the methacrylate controls.

CLINICAL SIGNIFICANCE

The addition of TU may produce less cytotoxic materials based on the increased conversion and reduced amount of unreacted extractables from its network after water storage.

Effect of thermally deposited siloxane-methacrylate coating on bonding to glass fibre posts

AIM

To evaluate the alterations promoted by a thermally deposited siloxane-methacrylate coating on the surface of glass fibre posts and their effect on the bond strength of resin-core materials to the posts.

METHODOLOGY

Fibre post surfaces were treated with experimental thermally deposited siloxane-methacrylate coatings or clinically available treatments (i.e. hydrogen peroxide and methylene chloride); nontreated posts were used as controls. The contact angles formed between the post surface and the water/adhesive were measured with a tensiometer. Scanning electron microscopy and electron dispersive spectroscopy were used to examine the topographies and chemical changes in the post surfaces following treatment. Surface roughness was evaluated with laser interferometry. Core resin was bonded to the fibre posts, and microtensile bond strength testing was subsequently performed. The data were individually submitted to anova and Tukey's tests (α = 0.05).

RESULTS

The water contact angle was reduced significantly (P < 0.05) by the thermally deposited siloxane-methacrylate coating. All treatments significantly increased the adhesive contact angle (P ≤ 0.016) compared to the control as well as the surface roughness (P ≤ 0.006) and the amount of Si on post surfaces. Greater percentages of Si were observed for the thermally deposited coating. The bond strength to the posts was significantly improved by the thermally deposited coating (P < 0.05), whereas the other treatments did not differ from the control.

CONCLUSION

Treating the surface of glass fibre posts with a thermally deposited siloxane-methacrylate coating improved the bond strength to resin-based materials. The coating could be performed by manufacturers of glass fibre posts in order to reduce the number of clinical steps required for luting posts into root canals.

The cost of excessive postoperative use of antimicrobials: the context of a public hospital

OBJECTIVE: To evaluate the improper use of antimicrobials during the postoperative period and its economic impact. METHODS: We conducted a prospective cohort study by collecting data from medical records of 237 patients operated on between 01/11/08 and 31/12/08. RESULTS: from the 237 patients with the information collected, 217 (91.56%) received antimicrobials. During the postoperative period, 125 (57.7%) patients received more than two antimicrobials. On average, 1.7 ± 0.6 antimicrobials were prescribed to patients, the most commonly prescribed antibiotic being cephalothin, in 41.5% (154) of cases. The direct cost of antimicrobial therapy accounted for 63.78% of all drug therapy, this large percentage being attributed in part to the extended antimicrobial prophylaxis. In the case of clean operations, where there was a mean duration of 5.2 days of antibiotics, antimicrobials represented 44.3% of the total therapy cost. CONCLUSION: The data illustrate the impact of overuse of antimicrobials, with questionable indications, creating situations that compromise patient safety and increasing costs in the assessed hospital.

Etching a Fiber Post Surface with High-concentration Bleaching Agents

Introduction

Commonly, resin composites/cements fail to achieve proper bonding to fiber posts when their surfaces have not been previously etched. This study evaluated the effect of the concentration and application mode of hydrogen peroxide on the surface topography and bond strength of resin composite to glass-fiber posts.

Methods and Materials

Fiber posts were immersed in 24% or 35% solutions (a high-concentration bleaching agent) of hydrogen peroxide (H2O2), or these solutions were applied over the post surface using a microbrush (n=10). Posts without any treatment were used as a control. After etching, the posts were silanated and an adhesive was applied. The posts were positioned in a mold, and a resin composite was incrementally inserted and light-cured. The post/resin assembly was serially sectioned into several beams that were subjected to a tensile bond strength test. The data were subjected to the two-way analysis of variance and Tukey test (α=0.05). The Dunnet's test was used to compare the experimental conditions to the control. The surface topography was analyzed using scanning electronic microscopy.

Results

The non-etched post presented a relatively smooth surface without fiber exposure. Except for the application of 24% H2O2, the other experimental conditions increased the number of exposed fibers and bond strength in relation to the control. Although immersion resulted in higher values for the 24% H2O2 application, the mode of application did not alter bond strength when 35% H2O2 was used.

Conclusions

The effect of the mode of application of H2O2 depended on its level of concentration. A high-concentration bleaching agent improved the bond strength of the resin composite to the post surface, regardless of which mode was used.

The Effect of Prophylaxis Method on Microtensile Bond Strength of Indirect Restorations to Dentin

The aim of this study was to evaluate the effect of different materials used for dentin prophylaxis on the microtensile bond strengths (μTBS) of adhesively cemented indirect composite restorations. Sixty bovine incisors had the buccal surface ground with wet #600-grit silicon carbide abrasive paper to obtain a flat exposed superficial dentin and were submitted to different prophylaxis protocols, as follows: 3% hydrogen peroxide (HydP); 0.12% chlorhexidine (Chlo); sodium bicarbonate jet (SodB); 50-μm aluminum oxide air abrasion (AirA); pumice paste (PumP), and control group–water spray (Cont). After prophylaxis protocols a resin composite block (3.0 mm × 5.0 mm × 5.0 mm) was adhesively cemented using dual resin cement (Rely X ARC). After 24 hours of water storage, specimens were serially sectioned perpendicular to the bonded interface into 1-mm-thick slices. Each specimen was trimmed with a diamond bur to an hourglass shape with a cross-sectional area of approximately 1.0 mm2 at the bonded area. Specimens were tested (μTBS) at 0.5 mm/min using a universal testing machine. Scanning electron microscopy was used to examine the effects of prophylaxis techniques on dentin. Bond strength data (MPa) were analyzed by one-way analysis of variance and failure mode by Fisher test (α=0.05). μTBS data, means (SD), were (different superscripted letters indicate statistically significant differences): AirA, 25.2 (7.2)a; PumP, 24.1 (7.8)a; Chlo, 21.5 (5.6)a; Cont, 20.6 (8.1)a; HydP, 15.5 (7.6)b; and SodB, 11.5 (4.4)c. The use of aluminum oxide air abrasion, pumice paste, and chlorhexidine before acid etching did not significantly affect μTBS to dentin; however, the use of hydrogen peroxide and sodium bicarbonate jet significantly reduced μTBS.

Influence of matrix metalloproteinase synthetic inhibitors on dentin microtensile bond strength of resin cements

This study evaluated the effect of dentin pretreatment with 2% chlorhexidine (CHX) or 24% ethylenediamine tetra-acetic acid gel (EDTA) on the dentin microtensile bond strength (μTBS) of resin cements. Composite blocks were luted to superficial noncarious human dentin (n=10) using two resin cements (RelyX ARC [ARC] and RelyX U100 [U100]) and three dentin pretreatments (without pretreatment-control, CHX, and EDTA). CHX was applied for 60 seconds on the acid-etched dentin in the ARC/CHX group, and for the same time on smear layer-covered dentin in the U100/CHX group. EDTA was applied for 45 seconds on smear-covered dentin in the U100/EDTA group, and it replaced phosphoric acid conditioning in the ARC/EDTA group for 60 seconds. After storage in water for 24 hours, specimens were prepared for microtensile bond strength testing. The results were submitted to two-way analysis of variance (ANOVA) followed by Tukey test. ARC produced significantly higher μTBS (p<0.05) compared to the U100, except when EDTA was used. For ARC, no pretreatment and CHX produced higher μTBS than EDTA. For U100, EDTA produced higher μTBS; no statistical difference occurred between CHX pretreatment and when no pretreatment was performed. While CHX did not affect immediate dentin bond strength of both cements, EDTA improved bond strength of U100, but it reduced dentin bond strength of ARC.

Distribution and population structure of the fish Cyphocharax gilbert (Characiformes: Curimatidae) in the lower Paraíba do Sul River, Brazil

The distribution and population structure of Cyphocharax gilbert in four areas of the lower Paraíba do Sul River and its major tributaries (22 degrees S, 43 degrees W) were analyzed between March 1989 and February 1990. The species was common throughout the area, preferring major rivers with high turbidity and sand-mud substrates and range of length and size of specimens found varied depending on the particular characteristics of the site. A predominance of females was found in only area. Nevertheless, in all areas the bimonthly analysis showed preponderance of one of the sexes in periods before or after spawning. Males prevailed in shorter length classes and females in longer ones. There was a prevalence of young in one area that probably was used as a growth and feeding zone. v.

Influence of the shape core on custom cast dowel and core removal by ultrasonic energy

The aim of this study was to assess the influence of the shape of custom cast dowel and cores on their removal by the use of ultrasound technique. Twenty-four single-rooted bovine teeth were prepared and had cast dowel fixed with zinc phosphate cement. The teeth were randomly divided into two groups: group I- received custom cast dowel and cores made without the coronal portion anatomy, simulating removal this portion with a bur, and group II- received cores that reproduced the coronal anatomy. Both were treated with an ultrasound device in two three-minute cycles (US). The force necessary for dowel removal was determined using a mechanical test machine. In the second stage of the study, the custom cast dowel and cores were again cemented and no ultrasound vibration was used on them (C). Data were submitted to the two-way anova (2 x 2) and Tukey test (P < 0.05), resulting in decreased tensile strength values (Kgf): GIC (49.85 +/- 11.10); GIIC (48.22 +/- 11.09); GIIUS (32.36 +/- 6.21) and GIUS (8.0 +/- 7.52). It was concluded that the shape of the core without the anatomic coronal portion facilitated removal of intra-radicular retention only when associated with the use of ultrasound.

[Magnesium and myocardial infarction. Brazilian aspects]

Most of the brazilian's territory is poor in magnesium (Mg) and an evaluation of urinary Mg indicated very low concentration of this cation in a normal population sample. The study of the behavior of plasmatic Mg in the acute phase of uncomplicated myocardial infarction permitted the following conclusions; a) during the first three days of the clinical course there is significant hypomagnesemia; b) magnesemia rises progressively during the three days of infarction, without however reaching normal levels. The lymphocytic magnesium also show the same behavior. Mg infusion in patients with acute myocardial infarction (four grams of MgSO4 during the first three days) reduced the incidences of arrhythmias, death and the size of infarction, in São Paulo. Another study in Bahia also showed reduction of mortality with infusion of 10 grams of MgSO4 in 24 hours. These studies about the protective role of Mg show potential limitations because the samples were small.