GHB and synthetic cathinones: clinical effects and potential consequences

Designer drugs belong to a group of legally or illegally produced substances that are structurally and pharmacologically very similar to illicit drugs. In the past, designer drugs were often used during all-night dance parties, but they are now consumed in multiple settings from college bars to parks to private house parties. Most of these club drugs can be bought on legal websites and home-delivered for private parties. Recently, legal highs have once again become a burning media issue across the world. Our review will focus on GHB and synthetic cathinones. Literature searches were conducted for the period from 1975 to July 2010 using PubMed, EMBASE, PsycInfo, Internet underground and governmental websites using the following keywords alone or in combination: designer drugs, club drugs, party drugs, GHB, synthetic cathinones, mephedrone, methylone, flephedrone, MDAI, and MDVP. Available epidemiological, neurobiological, and clinical data for each compound are described. There is evidence that negative health and social consequences may occur in recreational and chronic users. The addictive potential of designer drugs is not weak. Non-fatal overdoses and deaths related to GHB/GBL or synthetic cathinones have been reported. Clinicians must be careful with GBL or synthetic cathinones, which are being sold and used as substitutes for GHB and MDMA, respectively. Interventions for drug prevention and harm reduction in response to the use of these drugs should be implemented on the Internet and in recreational settings. Prevention, Information, Action, and Treatment are the main goals that must be addressed for this new potentially addictive problem.     

An analysis of the diagnostic methods for acute pulmonary embolism

In spite of numerous sophisticated investigative procedures, acute pulmonary embolism (PE) is very frequently misdiagnosed. In order to improve the diagnostic approach to PE, the sensitivity and specificity of the commonly used methods were reviewed in a group of 421 patients with angiographically proved PE without associated cardio-pulmonary disease. The specificity of diagnostic procedures was, by decreasing order: positive pulmonary angiography (to affirm) = negative perfusion lung scan (to eliminate) > chest X-ray clinical symptoms, positive perfusion lung scan, ECG, blood gas, serum enzymes.     

How to best measure femoral length and lateralisation after total hip arthroplasty on antero-posterior pelvic radiographs

Purpose

Various methods exist for measuring limb length and lateralisation after total hip arthroplasty. Most of them utilise standard anteroposterior (AP) pelvic radiographs, but their results can be affected by patient position during imaging and thus the position of the lower limb on the coronal plane. The aim of this study is to evaluate how commonly used measuring methods of limb lengthening and femoral offset are affected by the position of the lower limb in the coronal plane.

Methods

A standing pelvic AP radiograph post implantation of a right total hip prosthesis was digitised. The right femur and its femoral stem were digitally segmented, such that they could be positioned orthogonal to the pelvis horizontal reference, with 10° of adduction, and with 10° of abduction, with respect to the centre of rotation. Various limb lengths and implant lateralisation were also digitised. We obtained nine x-rays differing one to three variables. Twice four independent surgeons performed three femoral length measurement methods and femoral offset measurement methods. Intra and inter-observer error as well as the effect of the femoral position on the measurements were studied.

Results

With respect to length measurements, the distance between the centre of rotation (C) and the tip of the lesser trochanter (LT) increased by 3 mm per cm of lateralisation. This measurement was not affected by the hip position in abduction or adduction. The distance between the tip of the lesser or greater trochanter (GT) and the horizontal passing through the centre of rotation was strongly affected by the hip position in abduction or adduction. With respect to offset, the distance between the centre of rotation and the greater trochanter (C-GT) was the most consistent and was not affected by variations in lengths or femoral axis. At the level of the lesser trochanter, the distance of the femoral anatomical axis and to Perkin’s line was heavily influenced by the femoral position.

Conclusion

The C-LT distance was consistent in measuring limb length and the C-GT distance was reliable in determining femoral offset regardless of the relative position of the femur.

     

Compensation method for obtaining accurate, sub-micrometer displacement measurements of immersed specimens using electronic speckle interferometry

We proposed and validated a compensation method that accounts for the optical distortion inherent in measuring displacements on specimens immersed in aqueous solution. A spherically-shaped rubber specimen was mounted and pressurized on a custom apparatus, with the resulting surface displacements recorded using electronic speckle pattern interferometry (ESPI). Point-to-point light direction computation is achieved by a ray-tracing strategy coupled with customized B-spline-based analytical representation of the specimen shape. The compensation method reduced the mean magnitude of the displacement error induced by the optical distortion from 35% to 3%, and ESPI displacement measurement repeatability showed a mean variance of 16 nm at the 95% confidence level for immersed specimens. The ESPI interferometer and numerical data analysis procedure presented herein provide reliable, accurate, and repeatable measurement of sub-micrometer deformations obtained from pressurization tests of spherically-shaped specimens immersed in aqueous salt solution. This method can be used to quantify small deformations in biological tissue samples under load, while maintaining the hydration necessary to ensure accurate material property assessment.     

The VenaTech LP permanent caval filter: effectiveness and safety in the prevention of pulmonary embolism--a European multicenter study

PURPOSE: To evaluate (i) the appropriateness, safety, and patient outcomes after placement of the VenaTech LP caval filter and (ii) the success of filter insertion through various venous access routes. MATERIALS AND METHODS: An open multicenter prospective observational study was conducted in 12 European centers, including an initial part limited to four centers. Patients with common indications were eligible for inclusion after approval by an independent ethics committee. Over a 42-month period, 106 patients (46 men [43.4%], 60 women [56.6%]), 72.2 years +/- 13.3 of age (range, 37-97 y), with poor prognoses were included. Patients were examined 2-5 days after the procedure, then at 30 days +/- 5 and 90 days +/- 15 for clinical follow-up and filter assessment. Evaluation criteria were based on occurrence of pulmonary embolism (PE), adverse events, death, filter position, and caval patency. Data were available in 101 case report forms at days 2-5, in 75 at day 30 +/- 5, and in 60 at day 90 +/- 15. Two patients (1.9%) were lost to follow-up. RESULTS: The overall mortality rate was 20.8%. PE was present in 71 patients (67.0%). History of venous thromboembolic disease (VTED) was noted in 32 patients (30.2%), and recently diagnosed VTED was present in 101 patients (95.3%). Partial caval thrombosis was present before the procedure. Filter tilting of 10-45 degrees was seen in 3.9% of cases at days 2-5, 4.3% of cases at day 30 +/- 5, and 1.9% of cases at day 90 +/- 15. Follow-up evidenced neither clinical signs of PE nor significant device-related events. CONCLUSIONS: In a prospective patient cohort with a projected 3-month mortality rate of nearly 21.0% as a result of severe prognoses, the success of insertion via various venous access routes and the appropriateness and safety of the VenaTech LP caval filter were assessed. Findings at 90-day follow-up were free of symptomatic PE and device-related adverse effects.