The histomorphologic and morphometric study of asymptomatic hip arthroplasty. A postmortem study

The purpose of this study was to determine the histologic findings at the bone-cement interface in successful asymptomatic total hip replacements (THR) retrieved from patients at autopsy. The criteria for a successful hip arthroplasty were clinical, radiologic, and direct examination of the prosthesis at the time of harvesting. Twelve patients with a total of 14 cemented hip arthroplasties came to autopsy at a mean of 4.7 years after implantation. A detailed histomorphometric objective means of assessing the tissue response was applied to the membrane. The density of histiocytes correlated with the thickness of the membrane, the density of polyethylene particles, and the time after implantation. The fibrohistiocytic membrane in this group of patients was similar to that described in the literature in cases of loose THRs. These findings advance current understanding of transcellular particle transportation (directional exocytosis) in tissue reactions to endoprostheses of THR.     

Advanced practice nurses in emergency care settings: A demographic profile.

INTRODUCTION: Very little is known about clinical nurse specialists and nurse practitioners (advance practice nurses [APNs]) who practice in emergency care settings. The Advanced Practice Committee of the ENA sought to determine a profile of these individuals. METHODS: Surveys were distributed to all registrants at 2 ENA conferences and posted on the ENA Web site. This survey asked 17 questions concerning the demographic characteristics of the APN respondents (eg, education, experience, certification, state recognition, and practice area). The survey was completed by 166 APNs. RESULTS: APNs had considerable experience as ED registered nurses before becoming an APN. They obtained their APN education at the master's degree or post-master's degree level. State recognition was required for 89.2% of the APNs. The majority of APNs (61.4%) obtained their certification through the American Nurses Credentialing Center. Nurse practitioners were predominantly family nurse practitioners (43%), and clinical nurse specialists were either critical care clinical nurse specialists (8.9%) or had other certifications (5.9%). APNs provided services in both the main emergency department and the fast track (45.7%) and were relatively new to their role as an APN. DISCUSSION: Consistent with current educational and certification requirements, the vast majority of APNs held a master's degree. Although relatively new to their role as APNs in emergency care, they were nonetheless very experienced as ED registered nurses. The majority of APNs were certified, even though that is not required for practice in all states. Continued research is needed to identify the most effective utilization of APNs, document their contributions to patient care outcomes, and develop strategies to meet their educational and practice needs.     

MR pelvimetry--a practical alternative.

Pelvimetry remains a useful technique as part of the assessment of the term breech pregnancy where vaginal delivery is planned. MR pelvimetry is accurate, well tolerated and shows soft-tissue structures as well as bone. It avoids the potentially carcinogenic effects of ionising radiation and is thought to be completely safe for mother and fetus. A technique of MR pelvimetry is described which uses gradient-echo sequences. This quick, practical method makes minimal inroads into valuable scanning time, and may therefore be considered a potentially cost-effective alternative to conventional pelvimetry.     

Atypical hemolytic uremic syndrome in human immunodeficiency virus-1-infected children

We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters, both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains unknown and the role of HIV infection in its pathogenesis, although possible, is unclear. Received March 5, 1996; received in revised form and accepted October 15, 1996     

Administration to humans of ORG 21465, a water soluble steroid i.v. anaesthetic agent

Ten male volunteers received a 1-min i.v. infusion of a new water soluble steroid anaesthetic agent, ORG 21465. Individuals received doses ranging from 0.8 to 1.8 mg kg-1. All subjects experienced venous pain at the site of injection; those receiving 1.0 mg kg-1 or more became anaesthetized. There was no evidence of histamine release and apnoea did not occur. Excitatory phenomena were observed in all subjects and were dose related; no spikes were seen on the EEG. Pharmacokinetic analysis supported a three-compartment (non-weight- related) model with compartmental volumes V1, V2 and V3 of 4.31, 14.2 and 89.4 litre, respectively. Clearance from the central compartment V1 was 1.55 litre min-1. Inter-compartmental clearances Q1 and Q2 were 2.54 and 1.79 litre min-1. We found that ORG 21465 was an effective anaesthetic in humans. The relationship between sedation, anaesthesia and excitation requires further exploration.      

Cardiovascular evaluation in Turner syndrome: utility of MR imaging.

Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome.     

Survival following intentional massive overdose of 'Ecstasy'.

A case of intentional overdose with 18 'Ecstasy' tablets is described. 'Ecstasy' is a semi-synthetic hallucinogenic amphetamine and acute adverse reactions follow from the effects of sympathetic stimulation. To our knowledge this is the first reported case of massive intentional overdose reported in the literature.