Comparison of the Different Approaches to Saphenous Nerve Block

Background: The authors compared the efficacy of the different approaches to saphenous nerve block.

Methods: The following approaches to saphenous nerve block were compared in 10 volunteers: perifemoral, transsartorial, block at the medial femoral condyle, below-the-knee field block, and blockade at the level of the medial malleolus. Each volunteer underwent all five blocks, and the interval between blocks was 3-7 days. The sequence of injection was randomized by Latin square design. Sensory blockade at the medial aspects of the leg and foot and the strength of the anterior thigh muscles were noted.

Results: The transsartorial, perifemoral, and below-the-knee field block approaches were more effective than block at the medial femoral condyle in providing sensory anesthesia to the medial aspect of the leg. The transsartorial approach was more effective than block at the medial femoral condyle and below-the-knee field block in providing sensory anesthesia to the medial aspect of the foot. Compared with the perifemoral approach, the transsartorial approach did not cause weakness of the hip flexors and the knee extensors. In volunteers with partial numbness in the medial aspect of the foot, supplemental block of the medial dorsal cutaneous branch of the superficial peroneal nerve resulted in complete sensory blockade.     

Pleiotropy in Coffin-Lowry syndrome: Sensorineural hearing deficit and premature tooth loss as early manifestations

We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc.     

3β-Hydroxysteroid Dehydrogenase/Isomerase and Aromatase Activity in Primary Cultures of Developing Zebra Finch Telencephalon: Dehydroepiandrosterone as Substrate for Synthesis of Androstenedione and Estrogens

3β-hydroxysteroid dehydrogenase/Δ⁵−Δ⁴isomerase (3β-HSD) activity was measured in primary dissociated cell cultures prepared from telencephalons of developing zebra finches. 3β-HSD activity was confirmed after cultures were incubated with [7-³H]pregneno- lone (Preg) or (1,2,6,7-³H-) dehydroepiandrosterone (DHEA) and³H-progesterone (Prog) and³H-androstenedione (AE) were detected in the medium. Product identity was confirmed by recrystallizations and by HPLC analysis. When DHEA was used as substrate,³H-estradiol and³H-estrone were also detected in the culture medium, presumably derived from the aromatization of³H-AE or³H-T produced from³H-DHEA. To test this idea, cultures were incubated with³H-DHEA together with radioinert AE or with fadrozole HCl, a potent and specific aromatase inhibitor. In the presence of radioinert AE,³H-AE increased but metabolites of³H-AE decreased in the media; in the presence of fadrozole,³H-estrogens decreased but³H-AE and its androgenic metabolite³H-5β-androstanedione increased. These data demonstrate 3β-HSD activity in the songbird brain. The presence of Prog and estradiol in these cultures suggest that Preg and DHEA can potentially serve as substrates for the ultimate formation of active sex steroids in the songbird telencephalon.     

Inherited Neurodegenerative Disorders Caused by CAG/Polyglutamine Tract Expansions: Symposium Introduction

At the beginning of this decade, the American Association of Neurology decided that the 1990's should be labelled "the decade of the brain" for expected advances in our understanding of neurological disorders and neuroscience. By the end of this decade, clinicians and researchers who work in the field of inherited neurological disorders might well remember the 1990's as "the decade of the trinucleotide repeat". At the time of writing this introduction, eleven inherited neurological disorders have been found to be caused by expansions of trinucleotide repeats, and a twelfth trinucleotide repeat expansion mutation has been identified (6), although the gene containing this mutant triplet repeat has not been cloned to our knowledge (Table 1).     

Effect of positioning on oxygenation in single-lung transplant recipients.

BACKGROUND: Many benefits and adverse effects of positioning are related to changes in ventilation and perfusion. A number of unique factors related to the allograft make the effects of positioning difficult to determine in single-lung transplant recipients. OBJECTIVES: To determine the effect of 3 body positions (supine, lateral with allograft lung down, and lateral with native lung down) on oxygenation and blood flow in single-lung transplant recipients in the 24 hours immediately after surgery. METHODS: A quasi-experimental repeated-measures design with stratified assignment to 1 of 3 different sequencing patterns for turning group was used to study 15 transplant recipients, 9 with emphysema and 6 with fibrosis. Oxygenation, ventilation, and blood flow measures (heart rate, blood pressure) were assessed after each turn. The effect of ischemic reperfusion injury was also explored. RESULTS: The oxygenation, ventilation, and bloodflow variables did not differ significantly across group, diagnosis, or time. Oxygenation variables measured when the allograft lung was dependent did not differ significantly from such measurements obtained when the native lung was dependent. CONCLUSIONS: No single position maximizes oxygenation in the immediate postoperative period in single-lung transplant recipients. Although a single standard protocol for positioning cannot be supported, the study does support the idea that transplant recipients can be safely turned in the immediate postoperative period without compromising oxygenation or hemodynamic status.