Effect of routine clopidogrel use on bleeding complications after transbronchial biopsy in humans

STUDY OBJECTIVES: Clopidogrel is often prescribed for primary or secondary prevention of cardiovascular disease and has been associated with unwanted bleeding events. After having shown that transbronchial biopsy can safely be performed in pigs receiving clopidogrel, we sought to determine whether routine clopidogrel use increases the risk of bleeding after transbronchial lung biopsy in humans. DESIGN: Prospective cohort study. PATIENTS AND INTERVENTIONS: Data were collected on 604 patients without underlying coagulation problems who underwent transbronchial lung biopsy over 13 months. Clopidogrel was not discontinued before biopsy in patients who were using it. Transbronchial biopsies were performed, and the incidence of bleeding and other complications among patients receiving clopidogrel was compared with that of other patients. RESULTS: The study was stopped early because the bleeding rate in the clopidogrel-only group (n = 18) was excessive (89% [16 of 18 patients] vs 3.4% [20 of 574 control subjects; p > 0.001] and also in the group receiving clopidogrel and aspirin (100% [12 of 12 patients] vs 3.4% among control subjects [p > 0.001]. Bleeding rates were significantly higher in the clopidogrel group for each degree of bleeding severity: mild (27% vs 1.5%), moderate (34% vs 1.5%), and severe (27% vs 0.3%; p > 0.001 for all comparisons). All 12 patients receiving both aspirin and clopidogrel had bleeding: moderate in 6 patients and severe in 6 patients. All bleeding was controlled by endoscopic means. There were no fatalities or need for blood transfusions in the patients enrolled in the trial. CONCLUSIONS: Clopidogrel use greatly increases the risk of bleeding after transbronchial lung biopsy in humans and therefore should be discontinued before bronchoscopy with biopsies. Aspirin exacerbates the effect of clopidogrel on bleeding.     

Real-time electromagnetic navigation bronchoscopy to peripheral lung lesions using overlaid CT images: the first human study

STUDY OBJECTIVES: To characterize the feasibility, accuracy, and safety of the superDimension/Bronchus system (SDBS) [superDimension, Ltd; Hertzliya, Israel] in navigating to previously unreachable peripheral lung lesions and obtaining biopsy specimens. DESIGN: Open-label, prospective, controlled clinical study. SETTING: Pulmonary institute of a university-affiliated municipal hospital. PATIENTS: Thirteen adult candidates for nonemergency bronchoscopy who gave informed consent to participate. INTERVENTIONS: The patients underwent flexible bronchoscopy using the SDBS, which is based on real-time CT-guided electromagnetic navigation and is capable of reaching peripheral lung masses beyond the reach of the bronchoscope. A position sensor was used to navigate to and sample the various target lesions for biopsy. MEASUREMENTS AND RESULTS: Three-dimensional chest CT was followed by SDBS methodology for marking anatomic landmarks and the target lesion on a virtual bronchoscopy screen and for sampling the lesion. The SDBS assisted in obtaining positive biopsy diagnoses in 9 of 13 cases (69%), with an average navigation accuracy of 5.7 mm. There were no SDBS-related adverse events. CONCLUSIONS: The SDBS is safe and effective in navigating to peripheral lung lesions located beyond the optic limits of a standard flexible bronchoscope.     

Body and head position effects on regional lung ventilation in infants: an electrical impedance tomography study

Objective To determine the effects of body and head positions on the spatial distribution of ventilation in nonintubated spontaneously breathing and mechanically ventilated infants using electrical impedance tomography (EIT).Design and setting Prospective study in a neonatal intensive care unit.Patients Ten spontaneously breathing (gestational age 38 weeks, postnatal age 13 days) and ten mechanically ventilated infants (gestational age 35 weeks, postnatal age 58 days).Interventions Supine and prone postures with different head positions (midline and rotated to the left and right side).Measurements and results The distribution of ventilation in the chest cross-section was repeatedly determined from EIT data in each body/head position studied. During spontaneous breathing the tidal volumes in the left lung region were reduced in the supine posture with the head turned to the left as well as in the prone posture with the head rotated to either side when compared with the supine posture with the head in the midline position. During mechanical ventilation the tidal volumes in the left lung region were unaffected by the body and head position except for the prone posture combined with the leftward head rotation which reduced them. In both types of ventilation the tidal volumes in the right lung region were unaffected by the change in body/head position.Conclusion The results indicate that the spatial distribution of ventilation is influenced by the body and head position in spontaneously breathing infants. Prone posture with the leftward head rotation has the most prominent effect which is detectable even during mechanical ventilation.Electronic supplementary material The electronic reference of this article is . The online full-text version of this article includes electronic supplementary material. This material is available to authorised users and can be accessed by means of the ESM button beneath the abstract or in the structured full-text article. To cite or link to this article you can use the above reference.This article is discussed in the editorial available at:     

Efficiency of the polymer bur SmartPrep compared with conventional tungsten carbide bud bur in dentin caries excavation

SmartPrep is a rotating instrument for dentin caries excavation made from a special polymer. The manufacturer's product information stated that SmartPrep removes carious dentin selectively. This in vitro study compared the efficiency of SmartPrep with conventional tungsten carbide bud burs. Fifty extracted teeth were split in the center of a carious lesion. The 100 specimens were randomly divided into five groups. Five dentists were asked to excavate 10 teeth each: one half with SmartPrep and the corresponding half with conventional bud burs. The time needed for the caries excavation was measured. Subsequently, histological specimens were produced from all cavities and analyzed by light-microscope after Mallory-Azan-staining. The thickness of the remaining caries was measured (< 1 mm or > 1 mm). The time expended was analyzed using the paired t-test. The results were analyzed for the remaining caries and thickness of the carious layer for every tooth, using the non-parametric Wilcoxon test for combined random samples. A binary logistical regression was performed to determine the influence of the three variables (tooth, sections or bur) on the criteria "caries" or "carious layer thickness (> 1 mm)." The average time to excavate a cavity with SmartPrep was 208.1 seconds, and it was 228.32 seconds with conventional bud burs. The difference between the recorded times was not statistically significant (p > 0.05). In 37 of 50 teeth, the number of carious sections was higher in the SmartPrep group than in the bud bur group. In nine teeth, the quantity of carious sections was higher in the bud bur group than in the SmartPrep group. Four teeth showed no difference in the number of carious sections. The results were statistically significantly different (p < 0.001). In 30 teeth, the number of carious sections with a carious layer thicker than 1 mm was higher in the SmartPrep group compared with the bud bur group. In nine teeth, the number of carious sections was higher in the bud bur group than in the SmartPrep group. Eleven teeth showed no difference in thickness of the carious dentin layer. These results were statistically significantly different (p = 0.003). Binary logistical regression showed that only the variable "bur" (bud bur or SmartPrep) influenced the results concerning the criterion "caries" (p < 0.001).     

Analysis of unconventional approaches for the rapid detection of surface lectin binding ligands on human cell lines

For over a decade our laboratory has developed and used a novel histochemical assay using derivatized agarose beads to examine the surface properties of various cell types. Most recently, we have used this assay to examine lectin binding ligands on two human cell types, CCL-220, a colon cancer cell line, and CRL-1459, a non-cancer colon cell line. We found that CCL-220 cells bound specific lectins better than CRL-1459, and this information was used to test for possible differential toxicity of these lectins in culture, as a possible approach in the design of more specific anti-cancer drugs. Although we have examined the validity of the bead-binding assay in sea urchin cell systems, we have not previously validated this technique for mammalian cells. Here the binding results of the bead assay are compared with conventional fluorescence assays, using lectins from three species (Triticum vulgaris, Phaseolus vulgaris, and Lens culinaris) on the two colon cell lines. These lectins were chosen because they seemed to interact with the two cell lines differently.

Binding results obtained using both assays were compared for frozen, thawed and fixed; cultured and fixed; and live cells. Both qualitative and quantitative fluorescence results generally correlated with those using the bead assay. Similar results were also obtained with all of the three different cell preparation protocols. The fluorescence assay was able to detect lower lectin binding ligand levels than the bead assay, while the bead assay, because it can so rapidly detect cells with large numbers of lectin binding ligands, is ideal for initial screening studies that seek to identify cells that are rich in surface binders for specific molecules. The direct use of frozen, thawed and fixed cells allows rapid mass screening for surface molecules, without the requirement for costly and time consuming cell culture.     

Do asthma and allergy influence subsequent pet keeping? An analysis of childhood and adulthood

BACKGROUND: Asthma and allergy might influence the choice of keeping pets, leading to apparent protective effects of pets on allergic disease. OBJECTIVE: We investigated the effects of asthma and allergy on subsequent pet keeping in childhood and adulthood. METHODS: Information about asthma and pet keeping at ages 0 to 4, 5 to 15, 20 to 44, and 26 to 56 years was provided by 9812 subjects participating in the 9-year follow-up of the European Community Respiratory Health Survey. RESULTS: In childhood asthma debut at younger than 5 years was associated with less cat keeping at 5 to 15 years (odds ratio [OR], 0.60; 95% CI, 0.44-0.82), an effect only observed when the parents did not have asthma or allergy (P(interaction) = .045). Childhood asthma did not influence adult pet ownership, unless there were adult symptoms. Adults less often acquired cats at follow-up if they had 3 or more asthma symptoms (OR, 0.78; 95% CI, 0.64-0.95), were taking asthma medication (OR, 0.48; 95% CI, 0.31-0.74), had hay fever (OR, 0.75; 95% CI, 0.62-0.91), had atopy (OR, 0.75; 95% CI, 0.61-0.91), or had specific IgE to cat (OR, 0.57; 95% CI, 0.39-0.82) at baseline. Adults who already had pets usually continued keeping the same type of pet, except that the presence of 3 or more asthma symptoms was associated with less subsequent dog keeping (OR, 0.69; 95% CI, 0.53-0.89). Pet removal between surveys to reduce allergen was reported by 4.7%. CONCLUSION: Selective avoidance subsequent to asthma or allergy was observed for childhood cat keeping and adult cat acquisition. Avoidance would produce an apparent protective effect of cats on childhood asthma (large OR, 0.83). Avoidance was generally not observed for dogs or birds. CLINICAL IMPLICATIONS: A part of the protective effects of childhood cats on asthma and allergy can be attributed to selective avoidance.     

European birth cohort studies on asthma and atopic diseases: I. Comparison of study designs -- a GALEN initiative

BACKGROUND: The reasons for the rise in asthma and allergies remain unclear. To identify risk or protective factors, it is essential to carry out longitudinal epidemiological studies, preferably birth cohort studies. In Europe, several birth cohort studies on asthma and atopic diseases have been initiated over the last two decades. AIM: One of the work packages within the Global Allergy and Asthma European Network (GA(2)LEN) project was designed to identify and compare European birth cohorts on asthma and atopic diseases. The present review (part I) describes their objectives, study settings, recruitment process and follow-up rates. A subsequent review (part II) will compare outcome and exposure parameters. METHODS: For each birth cohort, we collected detailed information regarding recruitment process, study setting, baseline data (pregnancy, birth, parents/siblings) as well as follow-up rates, outcome and exposure parameters at each time point. RESULTS: We identified and assessed 18 European birth cohorts on asthma, allergic rhinitis and eczema. Six of these studies also focused on food allergies. The birth cohorts were mostly initiated in the 1990s with predominantly urban/metropolitan settings. Many studies were able to maintain high follow-up rates, even after five or more years. CONCLUSIONS: Due to the unique cooperation within the GA(2)LEN project a common database was established containing study characteristics of European birth cohorts on asthma and atopic diseases. This can be used as a basis for evaluating the possibility to pool data and perform meta-analyses, as well as to recommend criteria for conducting future birth cohorts.