Univariate fast initial response statistical process control with taut strings.

We present a novel real-time univariate monitoring scheme for detecting a sustained departure of a process mean from some given standard assuming a constant variance. Our proposed stopping rule is based on the total variation of a nonparametric taut string estimator of the process mean and is designed to provide a desired average run length for an in-control situation. Compared to the more prominent CUSUM fast initial response (FIR) methodology and allowing for a restart following a false alarm, the proposed two-sided taut string (TS) scheme produces a significant reduction in average run length for a wide range of changes in the mean that occur at or immediately after process monitoring begins. A decision rule for when to choose our proposed TS chart compared to the CUSUM FIR chart that takes into account both false alarm rate and average run length to detect a shift in the mean is proposed and implemented. Supplementary materials are available online.

[Advanced nurse triage for emergency department]. / Le triage infirmier avancé aux Urgences.

To cope with overcrowding, a consequence of their constant growth, emergency departments have implemented operational strategies based on triage systems. Despite its interest, nurse triage has been limited by several hindrances, and new strategies are emerging. Among those, advanced nurse triage, allowing a nurse to initiate the diagnostic process just after categorization of the patient, seems to be promising. A study on advanced nurse triage for patients presenting with chest pain has been conducted in the emergency department of the CHU of Liège. The encouraging results obtained following this new system demonstrate a reduction of the delay to management of patients, and a reduction of the total length of stay in the emergency unit mainly during overcrowding periods. Advanced nurse triage, in addition to a conventional triage during overcrowding periods, improves management of patients in terms of time and reduces the total time spent in the emergency department.

Confronté au problème de surpopulation, conséquence de leur fréquentation sans cesse croissante, les services d'urgence ont mis en place des stratégies opérationnelles basées sur des filières de soins organisées au départ de systèmes de triage des patients. Pareils outils ont démontré leur intérêt, mais s'avèrent aujourd'hui insuffisants, raison pour laquelle de nouvelles stratégies voient le jour. L'une d'elles, le triage infirmier avancé, permettant à un infirmier d'initier la démarche diagnostique juste après la catégorisation du patient, semble être une promesse d'avenir. Une étude portant sur un triage infirmier avancé pour les patients se présentant pour une douleur thoracique a été menée récemment au CHU de Liège. Les résultats encourageants de cette étude révèlent un gain de temps dans la prise en charge des patients en faveur de ce nouveau système et une durée totale de séjour aux urgences réduite, principalement en période de surpopulation. Il se confirme donc que le triage infirmier avancé, couplé à un triage classique, particulièrement en période de surpopulation, améliore la prise en charge des patients en termes de temps et réduit le temps total de séjour aux urgences, tout en garantissant la qualité, combattant, par là, la surpopulation.

[A rare cause of negative explora tory laparotomy in severe blunt trauma]. / Le cas clinique du mois. Une cause rare de lapararotomie exploratrice négative chez le polytraumatisé.

We report the case of a young man involved in a high velocity road traffic accident. He presented with multiple injuries and a shock. This shock was suspected to be caused by an intra-abdominal bleeding and an exploratory laparotomy was performed. The procedure did not identify any intra-abdominal bleeding and the source of bleeding was found lately: an intramuscular active bleeding in the dorsal and lumbar muscular compartments. This case was discussed in our local mortality and morbidity meeting.

Nous présentons le cas d'un jeune patient victime d'un accident de la circulation responsable de multiples lésions et d'un état de choc. Sur base de certains éléments cliniques et paracliniques à l'admission, une hémorragie intra-abdominale fut suspectée avec réalisation d'une laparotomie exploratrice. Celle-ci s'est révélée négative et la source du saignement, responsable du choc hémorragique, a été identifiée tardivement : un saignement actif au sein des loges musculaires dorsolombaires. Le cas a été discuté lors d'une de nos réunions locales de retour d'expérience afin d'en tirer des enseignements pour les futures prises en charge.

A Biomechanical Comparison Of Pin Configurations Used For Percutaneous Pinning Of Distal Tibia Fractures In Children.

BACKGROUND: Percutaneous pin fixation is often used in conjunction with closed-reduction and cast immobilization to treat pediatric distal tibia fractures. The goal of this procedure is to maintain reduction and provide improved stabilization, in effort to facilitate a more anatomic union. We conducted a biomechanical study of the torsional and bending stability of three commonly used pin configurations in distal tibia fracture fixation. METHODS: A transverse fracture was simulated at the metaphyseal/diaphyseal junction in 15 synthetic tibias. Each fracture was reduced and fixed with two Kirschner wires, arranged in one of three pin configurations: parallel, retrograde, medial to lateral pins entering at the medial malleolus distal to the fracture (group A); parallel, antegrade, medial to lateral pins entering at the medial diaphysis proximal to the fracture (group B); or a cross-pin configuration with one retrograde, medial to lateral pin entering the medial malleolus distal to the fracture and the second an antegrade, medial to lateral pin entering at the medial diaphysis proximal to the fracture (group C). Stability of each construct was assessed by resistance to torsion and bending. RESULTS: Resistance to external rotation stress was significantly higher in group A than group B (P = 0.044). Resistance to internal rotation stress was significantly higher in group C than group B (P = 0.003). There was no significant difference in torsional stiffness when comparing group A with group C. Under a medial-directed load, group B and C specimens were significantly stiffer than those in group A (28 N/mm and 24 N/mm vs. 14 N/mm for A; P = 0.001 and P = 0.009, respectively). CONCLUSIONS: None of the three pin configurations produced superior results with respect to all variables studied. Group A configuration provided the highest resistance to external rotation forces, which is the most clinically relevant variable under short-cast immobilization. Parallel, retrograde, medial to lateral pins entering at the medial malleolus provide the greatest resistance to external rotation of the foot while minimizing the potential for iatrogenic injury to soft tissue structures.

Obesity is associated with increased postoperative complications after operative management of distal humerus fractures.

BACKGROUND: Distal humerus fractures commonly require surgical intervention, including open reduction and internal fixation (ORIF) and, more recently in elderly, low-demand individuals, total elbow arthroplasty (TEA). The association of obesity with complications after either of these procedures has not previously been examined. METHODS: A national insurance database was queried for ORIF or TEA for management of a distal humerus fracture using procedural and diagnostic codes. Patients in each operative group were then divided into nonobese and obese cohorts. These cohorts were then queried for postoperative complications within 90 days after the surgical procedure using diagnostic and procedural codes. χ(2) tests were calculated to determine statistical significance, with P < .05 considered significant. RESULTS: A total of 6928 patients who underwent operative management of a distal humerus fracture were identified, including 4215 ORIF and 2713 TEA procedures. The obese ORIF patients had a significantly increased risk of 90-day local (odds ratio [OR], 2.5; P < .0001) and systemic (OR, 5.9; P < .0001) complications. The rates of postoperative infection, venous thromboembolism, and medical complications were significantly higher in the obese ORIF cohort than in nonobese patients. The obese TEA patients had a significantly increased risk of 90-day local (OR, 2.6; P < .0001) and systemic (OR, 4.4; P < .0001) complications. The rates of postoperative infection, venous thromboembolism, and medical complications were higher in the obese TEA cohort than in nonobese patients. CONCLUSIONS: Obesity is associated with significantly higher rates of complications after ORIF and TEA for distal humerus fractures than in nonobese patients.

Antibodies against Haemophilus influenzae type b in The Gambia: investigating the extent of protection across age groups.

Following a landmark clinical trial, the vaccine against Haemophilus influenzae type b (Hib) was introduced in The Gambia in 1997. Whilst the immunogenicity of this vaccine is well established subsequent to the doses administered under the EPI schedule, little data exists assessing longevity of protection, using serology. Such data are needed however to predict the susceptibility to Hib at the population level. To determine antibody persistence in 5-6 year old fully vaccinated Gambian children compared with older children, adolescents and young adults, 427 serum samples from healthy 5-37 year old participants were tested for Hib antibodies using VaccZyme Human Anti-Hib ELISA kits. 86% of the children who had received 3 doses of Hib vaccine in infancy had Hib antibody concentrations ≥0.15 mg/l at the age of 5-6 years. This proportion was 76% for adolescents who had also largely been vaccinated and 90% for adults who had never received Hib vaccine. Although most participants had anti-Hib antibody above concentrations putatively defined as protective, significantly fewer had concentrations thought to confer long-term protection. This suggests a population with insufficient or waning antibody that may be susceptible to breakthrough disease and transmission.

[Presentation of ELISA: a new triage algorithm suitable for emergency department]. / ELISA: echelle liégeoise de l'indice de sévérité à l'admission. Présentation d'un outil de tri original applicable au service des urgences.

Emergency departments are frequently overcrowded due to the imbalance between need and availability of care. It results that influx patients should be regulated by using a triage tool located at the entrance area. This process has been in development for almost 15 years.We propose a new algorithm of triage (ELISA or Liège Scale of severity index at admission) based on a five-score level of emergency from U1 (emergent) to U5 (non urgent). Such a stratification of the state of emergency is associated with a time-delay for the first medical contact (immediate to 120 min) and a corresponding track for providing optimal care (emergency care unit, B sector or bed, A sector or ambulatory and waiting room) which together fit the sorting for the right patient to the right resources in the right place at the right time. Our algorithm has a confident efficiency as evidenced by the comparison between initial score of emergency and patient's follow up (intensive care, hospital recovery and discharge).

[Epiploic appendagitis, an ignored diagnosis]. / L'appendagite épiploïque. Un diagnostic méconnu.

Epiploic appendagitis is the term used to describe the inflammation of an epiploic appendage. These small masses of fat distributed along the colon, from the caecum to the recto-sigmoid junction can inflammate by torsion, spontaneously or secondarily with the inflammation of an anatomical structure in the neighbourhood. Symptomatology may mimic retro-caecal appendicitis or diverticulitis and the diagnosis by CT avoids unnecessary surgery or hospitalization. Indeed, under conservative treatment by AINS and analgesics, symptomatology regresses in about five days. In this article, we relate the case of a patient with a typical clinical presentation, to remind the elements of this pathological entity.

[Rhabdomyolysis and hypothyroidism]. / Le cas clinique du mois. Rhabdomyolyse et hypothyroïdie.

We describe the case of a 29 year old patient who presented severe myalgias and asthenia for 3 months. First biological assessment revealed muscular lysis and raised transaminases. The following complementary screening showed major hypothyroidism with the presence of anti-microsomes antibodies, a carpian canal syndrome and a left ventricular systolic dysfunction. A diagnosis of hypothyroidic rhabdomyolysis consecutive to a Hashimoto disease was then mash. Patient was treated by hormonal thyroid substitution with a progressive improvement of muscular symptoms to complete recovery, and a concomitant normalization of cardiac and thyroid functions.

ACTIVE: a cognitive intervention trial to promote independence in older adults.

The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial is a randomized, controlled, single-masked trial designed to determine whether cognitive training interventions (memory, reasoning, and speed of information processing), which have previously been found to be successful at improving mental abilities under laboratory or small-scale field conditions, can affect cognitively based measures of daily functioning. Enrollment began during 1998; 2-year follow-up will be completed by January 2002. Primary outcomes focus on measures of cognitively demanding everyday functioning, including financial management, food preparation, medication use, and driving. Secondary outcomes include health-related quality of life, mobility, and health-service utilization. Trial participants (n = 2832) are aged 65 and over, and at entry into the trial, did not have significant cognitive, physical, or functional decline. Because of its size and the carefully developed rigor, ACTIVE may serve as a guide for future behavioral medicine trials of this nature.

Non-correlation of in vivo and in vitro parameters of Epstein-Barr virus persistence suggests heterogeneity of B cell infection.

Following primary infection Epstein-Barr virus (EBV) establishes a persistent infection which is maintained for the life-time of the host. EBV can be found in a small number of circulating B cells, but the nature of the virus-cell interaction has not been fully established. Several assay systems are used to quantify persistent EBV infection, including PCR amplification of EBV DNA and spontaneous outgrowth of lymphoblastoid cell lines in culture. More recently, outgrowth of EBV-positive B cell tumours in severe combined immunodeficient (SCID) mice inoculated with peripheral blood mononuclear cells (PBMC) from normal EBV-seropositive donors has also been used to study B cell infection in vivo. In the present study we have compared the results of these two biological assay systems with PCR detection of EBV DNA and a regression assay as a measure of host T cell immunity to EBV. PBMC from ten normal EBV-seropositive donors were studied and although each test gave consistent results on repeat assays, no correlation was found between any of the assays tested. This result suggests that each assay measures a separate aspect of EBV persistence in B cells, and indicates a previously unrecognized degree of heterogeneity in the B cell population in which EBV resides.

Cognitive aspects of recalling and reporting health-related events: Papanicolaou smears, clinical breast examinations, and mammograms.

This paper reports an examination of cognitive processes used by 178 women aged 50 years and older in retrieving information about the frequency with which they received Papanicolaou smears, mammograms, and clinical breast examinations. Women were selected from a health maintenance organization in which they had been enrolled for at least 5 1/2 years. The literature suggested that reporting of regular events such as these kinds of tests is likely to be based on schemas, which is an estimation technique in which events are reported in a format with generic content. Thus, if the procedure is believed to occur annually, the respondent will report receiving five tests in 5 years. The study attempted to evaluate whether use of episodic recall, in which respondents are forced to report individual events, would be more accurate than reports based on estimation using a schema format. The results indicated that most of the errors occurred in Papanicolaou smear reporting, which is consistent with the literature, and that the fewest errors occurred with mammograms. Regardless of the questionnaire format, respondents persisted in using schemas based on the date of annual physical examination. Most reporting errors occurred because the interval between examinations was estimated incorrectly.

Expression of the p53 induced tumor suppressor p21waf1/cip1 in ovarian carcinomas: correlation with p53 and Ki-67 immunohistochemistry.

Mutations of the p53 gene are the most common genetic alteration in malignant human tumors, including ovarian carcinomas of surface epithelial origin. A cyclin-dependent kinase inhibitor, p21waf1/cip1, is thought to be an important mediator of p53-induced cell cycle arrest. Although numerous studies have reported p53 expression and mutation in ovarian tumors, none have correlated p53 expression with that of its downstream effector, p21waf1/cip1. We studied p53 and p21waf1/cip1 expression by immunohistochemistry in 44 ovarian carcinomas of different histologic types and correlated these findings with each other and with proliferation as measured by expression of the Ki-67 nuclear antigen. Fifty percent of tumors expressed p53, whereas 34% expressed p21waf1/cip1. Clear cell carcinomas expressed p21waf1/cip1 significantly more often than other histologic types, and tumors with squamous differentiation showed higher p21waf1/cip1 expression in these areas. There was no correlation of p21waf1/cip1 expression with p53 expression, p53 mutation, or Ki-67 expression. p21waf1/cip1 appears to be induced independently of p53 in these tumors and may be associated with differentiation rather than proliferation.

Design and results of the Women's Health Study.

The Women's Health Study was a methodological experiment carried out in Chicago. More than 1,000 women took part; a comparison sample of 100 men was also included. The sample was selected from two sources. Most of the women and all of the men were selected from an area probability sample that had been screened to identify women in the eligible age range; the rest of the women were selected from rosters at cooperating abortion clinics and were known to have had an abortion. Questionnaires based on the one used in the National Survey of Family Growth were administered to the sample; the questionnaire included items on abortion, sexual behavior, and illicit drug use. The experiment examined five variables: whether the questionnaire began with a series of medical questions or with questions on pregnancy; whether the interview was conducted by a nurse or field interviewer; whether the interview was done at the respondent's home or outside the home; whether the interviewer or respondent administered the questions; and whether the data were collected on paper or via computer. Of the five experimental factors, the one with the most consistent effect was the method of administering the questions. Self-administration significantly increased the reported number of sexual partners, sexually transmitted diseases, and the level of condom use compared to administration by an interviewer. Computer assistance occasionally interacted with the site of the interview to effect reporting. The other two experimental variables-the version of the questionnaire and the data collection staff-had few discernible effects. None of the variables affected reported drug use over the lifetime.

Improving food frequency questionnaires: a qualitative approach using cognitive interviewing.

In an attempt to improve data quality and ease of administration of standard self-administered food frequency questionnaires, various alternative approaches were tried for inquiring about frequency of consumption, portion size, seasonal intake, and food preparation. Evaluation consisted of a cognitive interviewing method in which respondents verbalize their thought process while completing several variations of a questionnaire. Interviewers observed and asked follow-up probe questions to evaluate problems or inconsistencies verbalized by respondents. Consensus and judgment by interviewers and observers suggested several problematic features of food frequency questionnaires: formatting of questions about frequency and portion size; computing average frequencies for aggregated food items or for foods eaten seasonally; comprehension of many items; and ordering of foods. These findings led to cognitive refinement and innovations, which included detailed questions regarding preparation or use of low-fat varieties or other alternatives to help better describe specifics of intake for some foods; questions on seasonal intake for several foods; inclusion of portion size ranges; and additional response categories for frequency of intake. Cognitive interviewing is an important step in pinpointing cognitive problems in dietary questionnaires.

Baroreflex failure in a patient with central nervous system lesions involving the nucleus tractus solitarii.

Animal studies have shown the importance of the nucleus tractus solitarii, a collection of neurons in the brain stem, in the acute regulation of blood pressure. Impulses arising from the carotid and aortic baroreceptors converge in this center, where the first synapse of the baroreflex is located. Stimulation of the nucleus tractus solitarii provides an inhibitory signal to other brain stem structures, particularly the rostral ventrolateral medulla, resulting in a reduction in sympathetic outflow and a decrease in blood pressure. Conversely, experimental lesions of the nucleus tractus solitarii lead to loss of baroreflex control of blood pressure, sympathetic activation, and severe hypertension in animals. In humans, baroreflex failure due to deafferentation of baroreceptors has been previously reported and is characterized by episodes of severe hypertension and tachycardia. We present a patient with an undetermined process of the central nervous system characterized pathologically by ubiquitous infarctions that were particularly prominent in the nucleus tractus solitarii bilaterally but spared the rostral ventrolateral medulla. Absence of a functioning baroreflex was evidenced by the lack of reflex tachycardia to the hypotensive effects of sodium nitroprusside, exaggerated pressor responses to handgrip and cold pressor test, and exaggerated depressor responses to meals and centrally acting alpha 2-agonists. This clinicopathological correlate suggests that the patient's baroreflex failure can be explained by the unique combination of the destruction of sympathetic inhibitory centers (ie, the nucleus tractus solitarii) and preservation of centers that exert a positive modulation on sympathetic tone (ie, the rostral ventrolateral medulla).

Saliva cotinine and recent smoking--evidence for a nonlinear relationship.

Cotinine concentration in various body fluids is considered to be among the most useful markers of nicotine exposure currently available. Despite the prevailing consensus concerning cotinine's usefulness, cotinine's large intrasubject variability has led some to question the value of a single-point measurement. Several individual differences (for example, age, race, sex, and so forth) may affect cotinine excretion, and a peculiar nonlinearity between the number of cigarettes smoked and cotinine concentration has been reported previously in the literature. The purpose of this investigation was to examine the nature of the association between cotinine and reported number of cigarettes smoked after adjustment for the relationship between cotinine and age, a key individual difference known to affect drug absorption, distribution, metabolism, excretion, and tissue sensitivity. The authors examined the relationship between saliva cotinine and daily cigarette consumption in 116 smokers (mean age = 37.4 years; average number of cigarettes smoked daily = 20.1) who logged each cigarette into a hand-held computer as part of a study on the accuracy of recall. The Pearson correlation between saliva cotinine and the logged number of cigarettes smoked in the previous 17 hours (the time window corresponding to the half-life of cotinine) accounted for significantly more of the variance in cotinine than did the average logged number of cigarettes smoked daily during 5 days. Age was also significantly associated with cotinine levels. Further examination of the relationship between cotinine and amount smoked in the previous 17 hours revealed evidence for a significant nonlinear component. Inclusion of both age and a cubic nonlinear component of daily cigarette consumption resulted in further significant improvement in the amount of variance accounted for in cotinine levels. These results suggest that adjustments forage and the inclusion of a nonlinear component for cigarette consumption will result in more precise use of cotinine as a validation tool for existing differences in smoking levels.

Effects of dexamethasone and high terrestrial altitude on cognitive performance and affect.

This study examined the effects of dexamethasone and exposure to high terrestrial altitude on cognitive performance, affect, and personality. Cognitive performance was evaluated by five cognitive tasks, affect was evaluated by the Clyde Mood Scale and the Multiple Affect Adjective Check List, and personality was examined using the Minnesota Multiphasic Personality Inventory. Sixteen healthy young men received either dexamethasone (4 mg every 6 h) (n = 7) or placebo (n = 9) for 34 h prior to and 52 h after ascent to 4,300 m. Subjects treated with dexamethasone correctly performed more computer interaction and addition problems than did placebo-treated subjects. They also were less sleepy, dizzy, depressed, and anxious than placebo-treated subjects at altitude. No adverse effects on cognitive performance, affect, or personality were noted after dexamethasone was discontinued on the third day at altitude. Results indicate that dexamethasone at the present dose positively influences cognitive performance and mood states at altitude, but has no residual effect on personality.