Accuracy of Hemolyzed Potassium Levels in the Emergency Department.

INTRODUCTION: In the emergency department (ED), pseudohyperkalemia from hemolysis may indirectly harm patients by exposing them to increased length of stay, cost, and repeat blood draws. The need to repeat hemolyzed potassium specimens in low-risk patients has not been well studied. Our objective was to determine the rate of true hyperkalemia among low-risk, adult ED patients with hemolyzed potassium specimens. METHODS: We conducted this prospective observational study at two large (129,000 annual visits) academic EDs in the mid-Atlantic. Data were collected from June 2017-November 2017 as baseline data for planned departmental quality improvement and again from June 2018-November 2018. Inclusion criteria were an initial basic metabolic panel in the ED with a hemolyzed potassium level > 5.1 milliequivalents per liter that was repeated within 12 hours, age (≥18, and bicarbonate (HCO3) > 20. Exclusion criteria were age > 65, glomerular filtration rate (GFR) < 60, creatine phosphokinase > 500, hematologic malignancy, taking potassium-sparing or angiotensin-acting agents, or treatment with potassium-lowering agents (albuterol, insulin, HCO3, sodium polystyrene sulfonate, or potassium-excreting diuretic) prior to the repeat lab draw. RESULTS: Of 399 encounters with a hemolyzed, elevated potassium level in patients with GFR ≥ 60 and age > 18 that were repeated, we excluded 333 patients for age > 64, lab repeat > 12 hours, invalid identifiers, potassium-elevating or lowering medicines or hematologic malignancies.This left 66 encounters for review. There were no instances of hyperkalemia on the repeated, non-hemolyzed potassium levels, correlating to a true positive rate of 0% (95% confidence interval 0-6%). Median patient age was 46 (interquartile range [IQR] 34 - 56) years. Median hemolyzed potassium level was 5.8 (IQR 5.6 - 6.15) millimoles per liter (mmol/L), and median repeated potassium level was 3.9 (IQR 3.6 - 4.3) mmol/L. Median time between lab draws was 145 (IQR 87 - 262) minutes. CONCLUSION: Of 66 patients who met our criteria, all had repeat non-hemolyzed potassiums within normal limits. The median of 145 minutes between lab draws suggests an opportunity to decrease the length of stay for these patients. Our results suggest that in adult patients < 65 with normal renal function, no hematologic malignancy, and not on a potassium-elevating medication, there is little to no risk of true hyperkalemia. Further studies should be done with a larger patient population and multicenter trials.

[A case of farmer's lung associated with allergic bronchopulmonary aspergillosis]. / L'association inhabituelle de deux maladies pulmonaires immunoallergiques : un cas de pneumopathie d'hypersensibilité associée à une aspergillose bronchopulmonaire allergique.

Hypersensitivity pneumonitis and allergic bronchopulmonary aspergillosis are two forms of lung disease with presumed distinct immunoallergic mechanisms. We report the observation of a 38-year-old French farmer who, for one month, had fever and dyspnoea resistant to antibiotic therapy. A diagnosis of farmer's lung, and allergic bronchopulmonary aspergillosis was made on clinical, biological, functional and radiological evidence and according to the criteria established. The evolution was favorable with antigenic eviction and corticosteroid therapy. This observation is to our knowledge the 5th case that describes the association of hypersensitivity pneumonitis and allergic bronchopulmonary aspergillosis. It suggests the existence of risk factors and immunoallergic mechanisms common to both diseases and discusses the hypothesis that the same antigen(s) is (are) responsible for them.

Second hypersensitivity pneumonitis in the same patient caused by chinchillas

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Micropipette aspiration: A unique tool for exploring cell and tissue mechanics in vivo.

Cell and tissue mechanical properties are paramount in controlling morphogenesis. Microaspiration techniques allow measuring the absolute values of mechanical properties in space and time in vivo. Here, we explain how to build a microaspiration setup that can be used for both cellular and tissue scale measurements. At the cellular scale, microaspiration allows the mapping in space and time of surface tensions of individual interfaces within a tissue to understand the forces shaping it. At the tissue scale, microaspiration can be used to measure macroscopic mechanical properties such as the viscoelasticity and tissue surface tension that regulate the dynamics of tissue deformation. Based on a simple and cost-effective apparatus, these two complementary microaspiration techniques provide unique tools for exploring cell and tissue mechanics in vivo.

[Unilateral transudative pleural effusion and constritive pericarditis]. / Transsudat gauche et péricardite constrictive.

INTRODUCTION: Constrictive pericarditis is associated with thickening, fibrosis or inflammation of the pericardium which can lead to signs of right ventricle dysfunction. It is usually a chronic process which can present in a variety of ways. We present two cases of constrictive pericarditis discovered during the investigation of a left-sided pleural effusion. OBSERVATION: The cases represent two sorts of constrictive pericarditis, chronic and due to pericardial effusions. Their common feature was an increase in dyspnoea and a new pleural effusion on the left side. Their difference lies in the presence of a thickened calcified pericardium in one case and the presence of a pericardial effusion in the other. In both cases, non-invasive investigation failed to diagnose any cardiac disease. The presence of constrictive pericarditis was confirmed by right heart catheterization. Treatment by subtotal pericardectomy was effective. CONCLUSION: The thoracic manifestations of constrictive pericarditis are most commonly recurring bilateral pleural effusions. The mode of presentation may be an exudative, or transudative effusion. Unilateral pleural involvement, fibrosis, chylothorax or tumour like presentations may occur. A diagnosis of constrictive pericarditis should be considered in these clinical contexts and an examination of the pericardium performed. Cardiac catheterization can help in the differential diagnosis.

[Ketoacidosis at time of diagnosis of type 1 diabetes in children and adolescents: effect of a national prevention campaign]. / Effet à un an de la campagne nationale de prévention de l'acidocétose au moment du diagnostic de diabète de type 1 chez l'enfant et l'adolescent.

The aim of the study was to evaluate, after the first year of a national information campaign, the effect on the frequency and severity of diabetic ketoacidosis (DKA) at diagnosis of type 1 diabetes (T1D) in children and adolescents in France. The following data were collected during a 2-year period in people younger than 15 years of age at diagnosis of T1D, in 146 pediatric centers: age, sex, duration of symptoms, patient's previous care, clinical and biological signs, and family history of T1D. DKA was defined as pH<7.30 or bicarbonate<15mmol/L, severe DKA as pH<7.10 or bicarbonate <5mmol/L. During the 2nd year, an information campaign targeting health professionals and families was launched with the objective of reducing the time to diagnosis. Data were compared between the year before the campaign (year 0) and the first year of the campaign (year 1). The number of new cases of T1D was 1299 for year 0 and 1247 for year 1. Between year 0 and year 1, the rate of DKA decreased from 43.9% to 40.5% (P=0.08), exclusively due to the decrease of severe DKA from 14.8 to 11.4% (P=0.01). In the 0- to 5-year-old and 5- to 10-year-old age groups, the relative decrease in the rate of DKA was 13% and 15%, and 23% and 41% for severe DKA, respectively. In patients referred to the hospital by a pediatrician or who came at the family's initiative, the decrease was 34% and 7%, and 39% and 32% for severe DKA, respectively. No change was observed in the 10- to 15-year-old group or in those children who were referred by a general practitioner. In multivariate analyses, a higher DKA rate was associated with the young age of the child (<5 years), being hospitalized at the parents' initiative rather than being referred by a doctor, and the absence of a family history of T1D. A higher rate of severe DKA was associated with these last two factors but not with the child's age. The frequency of DKA at diagnosis of type 1 diabetes remains high in children and adolescents, but the first year of an information campaign decreased it. The results have also helped better define the strategy and targets of the continuing prevention campaign, to more efficiently reduce the morbidity and mortality of T1D at diagnosis in children and adolescents in France.

Regular physical activity reduces the effects of Achilles tendon vibration on postural control for older women.

The aim was to determine in what extent physical activity influences postural control when visual, vestibular, and/or proprioceptive systems are disrupted. Two groups of healthy older women: an active group (74.0 ± 3.8 years) who practiced physical activities and a sedentary group (74.7 ± 6.3 years) who did not, underwent 12 postural conditions consisted in altering information emanating from sensory systems by means of sensory manipulations (i.e., eyes closed, cervical collar, tendon vibration, electromyostimulation, galvanic vestibular stimulation, foam surface). The center of foot pressure velocity was recorded on a force platform. Results indicate that the sensory manipulations altered postural control. The sedentary group was more disturbed than the active group by the use of tendon vibration. There was no clear difference between the two groups in the other conditions. This study suggests that the practice of physical activities is beneficial as a means of limiting the effects of tendon vibration on postural control through a better use of the not manipulated sensory systems and/or a more efficient reweighting to proprioceptive information from regions unaffected by the tendon vibration.

Ketoacidosis at diagnosis of type 1 diabetes in French children and adolescents.

OBJECTIVES: This study aimed to evaluate the frequency of diabetic ketoacidosis (DKA) and its associated factors at the diagnosis of type 1 diabetes (T1D) in French children and adolescents prior to launching a public-health campaign of information to prevent DKA. PATIENTS AND METHODS: Over a 1-year period, 1299 youngsters (aged < 15 years) were diagnosed with T1D at 146 paediatric centres in all regions of France. Age, gender, duration of symptoms, patient's pathway to diagnosis, clinical and biological signs, and family history of T1D were collected for each newly diagnosed patient. DKA was defined as pH < 7.30 or bicarbonate < 15 mmol/L, and severe DKA as pH < 7.10 or bicarbonate < 5 mmol/L. RESULTS: At the time of diagnosis, 26% of the children were aged 0-5 years, 34% were 5-10 years and 40% were 10-15 years. The overall prevalence of DKA was 43.9% (0-5 years: 54.2%; 5-10 years: 43.4%; and 10-15 years: 37.1%) and 14.8% for severe DKA (0-5 years: 16.6%; 5-10 years: 14.4%; and 10-15 years: 13.9%; < 2 years: 25.3%). Severe DKA was more frequent when the child was hospitalized at the family's behest (26.6%) than when referred by a general practitioner (7.6%) or paediatrician (5.1%; 30.6%, 53.7% and 9.2%, respectively, by patients' age group). The frequency of DKA decreased to 20.1% (severe DKA: 4.4%) in families with a history of T1D. Multivariate analysis showed that age, pathway to diagnosis, duration of polyuria/polydipsia (< 1 week) and family history of T1D were associated with the presence of DKA, while pathway to diagnosis and family history of T1D were associated with severe DKA. CONCLUSION: DKA at the time of T1D diagnosis in children and adolescents is frequent and often severe. Patients' age, pathway to hospitalization and family history of diabetes were the main factors associated with DKA. These data suggest that a public-health campaign to prevent DKA at diagnosis can help reduce the frequency of DKA and also provide baseline data for evaluating the efficacy of such a campaign.

Electrical stimulation superimposed onto voluntary muscular contraction reduces deterioration of both postural control and quadriceps femoris muscle strength.

Fatiguing exercise of the quadriceps femoris muscle degrades postural control in human subjects. The aim of this work was to compare the effects of the fatigue of the quadriceps femoris induced by voluntary muscular contraction (VC), and by electrical stimulation (ES) superimposed onto voluntary muscular contraction (VC+ES), on postural control and muscle strength. Fourteen healthy young adults participated in the study. Postural control and muscle strength were evaluated using a stable force platform and an isokinetic dynamometer, respectively, before (PRE condition) and after the completion of each fatiguing exercise (immediately: POST condition; after a 5 min recovery time: POST 5 condition). In POST, both postural control and muscle strength were impaired by both fatiguing exercises. However, the impairment was higher for VC than for VC+ES. In POST 5, for both fatiguing exercises, postural control recovered its initial level while muscle strength did not. These results suggest that superimposing ES onto voluntary muscular contractions (VCs) impaired muscle strength and postural control less than did VCs alone. However the duration of recovery of these two neurophysiological functions did not differ for the two fatiguing exercises. For both exercises, postural control was restored faster than the ability to produce muscular strength.

European reference equations for CO and NO lung transfer.

The aim of the present study was to calculate reference equations for carbon monoxide and nitric oxide transfer, measured in two distinct populations. The transfer factor of the lung for nitric oxide (T(L,NO)) and carbon monoxide (T(L,CO)) were measured in 303 people aged 18-94 yrs. Measurements were similarly made in two distant cities, using the single-breath technique. Capillary lung volume (V(c)) and membrane conductance, the diffusing capacity of the membrane (D(m)), for carbon monoxide (D(m,CO)) were derived. The transfer of both gases appeared to depend upon age, height, sex and localisation. The rate of decrease in both transfers increased after the age of 59 yrs. T(L,NO)/alveolar volume (V(A)) and T(L,CO)/V(A) were only age-dependent. The mean T(L,NO)/T(L,CO) was 4.75 and the mean D(m)/V(c) was 6.17 min(-1) x kPa(-1); these parameters were independent of any covariate. V(c) and D(m,CO) calculations depend upon the choice of coefficients included in the Roughton-Forster equation. Values of 1.97 for D(m,NO)/D(m,CO) ratio and 12.86 min x kPa(-1) for 1/red cell CO conductance are recommended. The scatter of transfer reference values in the literature, including the current study, is wide. The present results suggest that differences might be due to the populations themselves and not the methods alone.

Early onset of pulmonary gas exchange disturbance during progressive exercise in healthy active men.

Some recent studies of competitive athletes have shown exercise-induced hypoxemia to begin in submaximal exercise. We examined the role of ventilatory factors in the submaximal exercise gas exchange disturbance (GED) of healthy men involved in regular work-related exercise but not in competitive activities. From the 38 national mountain rescue workers evaluated (36 +/- 1 yr), 14 were classified as GED and were compared with 14 subjects matched for age, height, weight, and maximal oxygen uptake (VO2 max; 3.61 +/- 0.12 l/min) and showing a normal response (N). Mean arterial PO2 was already lower than N (P = 0.05) at 40% VO2 max and continued to fall until VO2 max (GED: 80.2 +/- 1.6 vs. N: 91.7 +/- 1.3 Torr). A parallel upward shift in the alveolar-arterial oxygen difference vs. %VO2 max relationship was observed in GED compared with N from the onset throughout the incremental protocol. At submaximal intensities, ideal alveolar PO2, tidal volume, respiratory frequency, and dead space-to-tidal volume ratio were identical between groups. As per the higher arterial PCO2 of GED at VO2 max, subjects with an exaggerated submaximal alveolar-arterial oxygen difference also showed a relative maximal hypoventilation. Results thus suggest the existence of a common denominator that contributes to the GED of submaximal exercise and affects the maximal ventilatory response.

[Diagnostic use of oxygen consumption and gas exchange in exercise testing]. / Usage diagnostique de la consommation d'oxygène et des échanges gazeux au cours de l'épreuve d'exercice.

The interpretation of cardio-pulmonary exercise testing is usually performed on successive decisional organigrams which are based on the normality of two initial main branchpoints i.e., Vo2max and ventilatory threshold (VThr). This didactic approach leads however to a simplistic approach of exercise pathophysiology because the answer to the two original branchpoints (Vo2max and VThr) is mainly binary whereas the physiological meaning of these two parameters is multifactorial. Thus, we propose a methodic analytical approach which allows to integrate step by step the various informations concerning aerobic capacity, ventilatory and cardiocirculatory responses, and acidobasic status. After a purely descriptive analysis of data , a first synthesis describes the physiopathological behaviour during exercise and states the specificity of these informations excluding usual confounding factors. The comparison between the functional data and the clinical informations allows to propose some physiopathological hypothesis by confronting several complementary approaches: physiological, physiopathological and clinical ones. This method seems to be more adapted to the clinical diagnostic use of such a physiological investigation because it is sensitive, reproducible but not specific.

Influence of the composition of a meal taken after physical exercise on mood, vigilance, performance.

The metabolic and behavioral effects of nutrients after exercise on vigilance level, performance, and mood have been minimally studied and have given contradictory results. In order to increase the understanding of the relationships between nutrition, exercise and performance, this experiment compared the effects on mood and performance of a protein- rich meal and a protein- poor meal, eaten just after an acute session of exercise. Vigilance and mood were evaluated by visual analog scales, and memory was measured by memory search task from the AGARD STRES battery, based on the Sternberg paradigm. Forty-two subjects were involved in this experiment. All subjects participated in the study of the effect of exercise after two kinds of meals (protein and nonprotein). Two groups of fourteen subjects we used to evaluate the effect of the exercise and the effect of the delay of meal intake after exercise in the two kinds of diet. The results show no difference in memory performance between exercise and rest conditions, nor between "protein" and "no protein" meal groups. They do show, however, that subjects feel happier after a meal with protein than after a meal without protein. The effects of the "no protein" meal on drowsiness differ with the glucide content of the meal. Subjects are less drowsy when they eat between 125 and 150 g of glucide than when they eat more than 150 g. The rousing effect induced by physical exercise is counterbalanced when subjects eat more than 150 g of carbohydrate. The anxiolytic effect of glucide is re-established.

Effects of indomethacin and polyunsaturated fatty acid diet on exercise-induced hypoxaemia in master athletes.

We have previously reported a reduction in exercise-induced hypoxaemia following polyunsaturated fatty acid supplementation (PUFA). Although this might have been explained by increases in membrane fluidity, a clear explanation could not be provided due to potentially confounding influences of series-2 prosta- glandin mediated effects resulting from PUFA. In this investigation, ten master athletes [mean age 48.1 (SEM 6) years, maximal oxygen uptake (VO2max) 3.39 (SEM 0.21) l x min(-1)] completed a maximal cycling test (Ctrl) which was repeated after the administration of 150 mg of indomethacin to inhibit prostaglandin synthesis, both before and after 6 weeks of 3.66-g PUFA x day(-1). Cardiorespiratory parameters were obtained simultaneously with brachial arterial blood sampling for partial pressure of oxygen in arterial blood (PaO2), partial pressure of carbon dioxide in arterial blood (PaCO2), pH, oxygen saturation in arterial blood and lactate concentration determinations. A significant decrease in PaO2 (mmHg) from rest [93 (SEM 1.5)] was observed for exercise intensities of more than 40% VO2max in Ctrl reaching 75.9 (SEM 2.1) at VO2max. PUFA resulted in a 5.0 (SEM 0.68) mmHg upward shift (P < 0.05) in the PaO2-oxygen uptake relationship, reducing the difference in partial pressure of oxygen between alveolar air and arterial blood (P(A-a)O2) at VO2max [Ctrl 36 (SEM 1.6) vs PUFA 33 (SEM 2.2) mmHg] while PaCO2, remained unchanged. Indomethacin had no effect on either PaO2, ideal partial pressure of oxygen in alveolar gas or P(A-a)O2 in either Ctrl or after PUFA. In contrast, the fall in pH was significantly reduced after indomethacin while VCO2, PaCO2 and lactacidaemia remained unchanged. These observations confirm an effect of PUFA on exercise PaO2 behaviour which does not appear to be mediated by the influence of a series-2 prostaglandin.

Metabolic chiral inversion of anti-inflammatory 2-arylpropionates: lack of reaction in liver homogenates, and study of methine proton acidity.

1. Enrichment in the (S)-enantiomers for (R)-flurbiprofen, (R)-naproxen, (R)-suprofen and (R;S)-ibuprofen was investigated in various subcellular hepatic preparations containing coenzyme A. While such preparations were able to form hippuric acid from benzoic acid, the chiral inversion was never seen. 2. Using 2-dimethylaminoethanethiol 2-phenylpropionate (DEPP) as a model acyl thioester, the acidity of the methine proton was investigated by monitoring the proton/deuterium exchange occurring in deuterated solvents using high-resolution n.m.r. The compound was inert up to 22 h in D2O at 37 degrees C and pD 7.4. In pure methanol or a methanol-water mixture, only solvolysis was seen. In contrast, competitive hydrolysis (k = 0.005 h-1) and proton/deuterium exchange (k = 0.09 h-1) were seen in a CD3CN/D2O (50:50) mixture at 37 degrees C. 3. It is speculated that the failure to characterize chiral inversion of 2-arylpropionates in subcellular preparations may be due to the absence of a microenvironment of adequately moderate polarity.