Preventing the withdrawal response associated with rocuronium injection: a comparison of fentanyl with lidocaine

We compared the efficacy of IV fentanyl with IV lidocaine as pretreatment for the prevention of withdrawal response after rocuronium injection. For this prospective, randomized, placebo-controlled, double-blind study we recruited 90 patients aged between 18 and 65 yr, ASA physical status I or II, who had undergone elective surgery requiring general anesthesia and positive pressure ventilation. Patients were randomly allocated to 1 of 3 groups: group F received 2 mL IV fentanyl 50 microg/mL (100 microg), group L received 2 mL of preservative-free lidocaine 2% (40 mg), and group P (placebo) received 2 mL of normal saline. The incidence of withdrawal response after rocuronium was 57%, 30%, and 7% in the placebo, lidocaine, and fentanyl groups, respectively. We found a significant reduction in incidence of withdrawal response in both the fentanyl and lidocaine groups when compared with the placebo group (P < 0.05), with the fentanyl group being most effective (P < 0.05). In conclusion, both fentanyl and lidocaine are effective clinical treatments to alleviate the withdrawal response associated with rocuronium injection, with fentanyl being more effective.     

Management of ovarian cysts with aspiration and methotrexate injection

PURPOSE: To evaluate prospectively ultrasonography (US)-guided cyst aspiration and methotrexate injection in the management of simple and endometriotic ovarian cysts in selected patients. MATERIALS AND METHODS: Authors obtained informed patient consent and approval from hospital ethics committee. Study included 162 female patients (aged 15-77 years) with simple or endometriotic ovarian cysts (3.0-10.6 cm) at a tertiary hospital. Criteria for inclusion in the study were (a) persistence of the cyst for at least 6 months, (b) benign appearance of the cyst at US, and (c) normal serum CA-125 level measurement before the procedure. Authors performed transabdominal aspiration of the cysts with direct US guidance and injection of methotrexate (30 mg). Cytologic examination was performed in all cases. Follow-up US was performed at 1, 3, and 6 months. If the cyst persisted, the procedure could be repeated. Main outcome measure was resolution or persistence of cysts. chi(2) Test or Mantel-Haentszel chi(2) tests for univariate analysis and multiple logistic regression were used for multivariate statistical analysis. RESULTS: Of 162 patients, 148 were available for follow-up. Malignant cells were not found in any of the cases at cytologic examination. At follow-up US, cysts had disappeared in 124 patients (83.8%) and persisted in 24 (16.2%). Cyst diameter proved to be a significant prognostic factor for cyst resolution (P = .01). No major complications were observed. Patients received neither analgesia nor antibiotics. CONCLUSION: US-guided transabdominal aspiration of cyst fluid and subsequent methotrexate injection appears to be an alternative treatment for both simple and endometriotic ovarian cysts in selected cases.     

Effects of exercise training on vascular function in obese children

OBJECTIVES: Atherosclerosis is a disease that begins in childhood; endothelial dysfunction is its earliest detectable manifestation, and primary prevention strategies are likely to be most effective if instituted early. The aim of this study was to characterize the impact of obesity on vascular function in young children and to determine whether an exercise program improves abnormalities in vascular function. STUDY DESIGN: The influence of 8 weeks of exercise training was examined in 14 obese subjects, 8.9 +/- 0.4 years of age, with the use of a randomized crossover protocol. Conduit vessel endothelial function was assessed by means of high-resolution ultrasound and flow-mediated dilation of the brachial artery (FMD). RESULTS: Exercise training did not change subcutaneous fat mass, body weight, or body mass index. FMD in the obese group was significantly impaired relative to matched control subjects at entry (6.00% +/- 0.69% to 12.32% +/- 3.14%, P <.0001). FMD significantly improved with exercise training (7.35% +/- 0.99%, P <.05) in the obese group. CONCLUSIONS: Conduit vessel FMD, a validated surrogate measure of early atherosclerosis, was impaired in obese children but improved as a result of exercise training. This study supports the value of an exercise program in the treatment of obese children in a primary prevention setting.     

Nickel content of as-received and retrieved NiTi and stainless steel archwires: assessing the nickel release hypothesis

This study assesses the nickel content of as-received and retrieved stainless steel and NiTi archwires alloys. New and used brand-matched, composition-matched, and cross section-matched archwires were subjected to scanning electron microscopy and energy-dispersive electron probe microanalysis. Elemental analysis was performed on three randomly selected areas, and the nickel content, expressed as ratios of Ni/Ti (in NiTi wires) or Ni/Fe (in stainless steel), was statistically analyzed with a t-test (alpha = .05). No changes were detected with respect to Ni content ratios between as-received and retrieved NiTi or stainless steel wires, suggesting an absence of nickel release. Wear and delamination phenomena on the wire surface and the formation of galvanic couple between the stainless steel wires and bracket brazing materials intraorally may modify the corrosion susceptibility of the wire alloys in clinical conditions.     

Tensile properties of orthodontic elastomeric chains

The purpose of this investigation was to assess the permanent elongation, tensile strength and toughness of elastomeric chains. Two types (open and closed chains, i.e. with and without an intermodular link) of three brands of elastomeric module yielding six groups were included in the study. Specimens with equal numbers of loops were measured and classified into four groups based on their ageing state: (a) as-received; (b) subjected to a 24 hour steady strain in air determined as 50 per cent of original length; (c) exposed intraorally for 24 hours; and (d) retrieved following 3 weeks of intraoral exposure. All specimens were subjected to tensile stress and their behaviour was analysed with three-way ANOVA and Tukey's multiple comparison test at alpha = 0.05 level of significance, with brand, type (open or closed chains), and treatment variables serving as discriminating variables. Modular geometry or design were found not to have significant effects on elongation, probably due to the substantial variation in chain shape, modular size, and link length among products of the same category. Similarly, no correlation was identified between specimen treatment and the tensile strength of elastomers. The toughness results were not consistent with the group rankings for tensile strength, probably because of variation in the elastic and plastic deformation of specimens upon loading.