Incidence of Suture-Method Catheter Dislocation with Femoral Nerve Block and Femoral Triangle Block after Total Knee Arthroplasty

Catheter dislocation with continuous peripheral nerve blocks represents a major problem in clinical settings. There is a range of factors affecting the incidence of catheter dislocation, including catheter type. This study aimed to assess the incidence of suture-method catheter (SMC) dislocation 24 h after total knee arthroplasty (TKA), with continuous femoral nerve block (CFNB) and continuous femoral triangle block (CFTB), respectively. In the prospective randomized trial, 40 patients qualified for TKA with SMC and were divided into two groups, those who received CFNB (Group 1, n = 20) and those who received CFTB (Group 2, n = 20). After 24 h, the degree of catheter displacement (cm), pain intensity (NRS) and opioid consumption (mg) was assessed. The catheter dislocation rates were found to be 15% in Group 1 versus 5% in Group 2, with the catheter dislocated by 0.83 cm (SD = ±0.87) and 0.43 cm (SD = ±0.67), respectively. There were no differences in NRS score (p = 0.86) or opioid consumption (p = 0.16) between the groups. In each case, a displaced catheter was successfully repositioned by pulling, which clinically resulted in a lower NRS score. The results of the study suggest that CFTB with SMC may be used after TKA with a good effect, as it is associated with low catheter dislocation rates and an adequate analgesic effect.

Successful treatment of anti-NMDA receptor encephalitis with a prompt ovarian tumour removal and prolonged course of plasmapheresis: A case report

Anti-N-methyl-d-aspartate-receptor (NMDAR) encephalitis is an uncommon autoimmune disorder with a wide spectrum of neuropsychiatric symptoms. There is a great requirement to emphasize the importance of a multidisciplinary team approach in the process of diagnosis and treatment of the potentially fatal condition, including psychiatrists, neurologists, gynaecologists and intensivists. Physicians must be aware that psychiatric and neurological disorders, which are typical features for NMDAR encephalitis in young women with ovarian tumours, may progress into status epilepticus and respiratory insufficiency. This disease can only be successfully treated with prompt surgical intervention and an early implementation of a wide array of immunosuppressive therapies. Optimal timing of initiation of therapeutic plasma exchange, as well as duration of treatment necessary to achieve desirable outcomes in patients with NMDAR remains unknown. The present case report aims to raise awareness about the importance of early implementation of this potentially life-saving therapy and continuing the treatment courses until full subsidence of symptoms.

Determination of the Avogadro constant by counting the atoms in a 28Si crystal

The Avogadro constant links the atomic and the macroscopic properties of matter. Since the molar Planck constant is well known via the measurement of the Rydberg constant, it is also closely related to the Planck constant. In addition, its accurate determination is of paramount importance for a definition of the kilogram in terms of a fundamental constant. We describe a new approach for its determination by counting the atoms in 1 kg single-crystal spheres, which are highly enriched with the 28Si isotope. It enabled isotope dilution mass spectroscopy to determine the molar mass of the silicon crystal with unprecedented accuracy. The value obtained, NA = 6.022,140,78(18) × 10(23) mol(-1), is the most accurate input datum for a new definition of the kilogram.