Ascending thoracic aortic aneurysm size at presentation and growth by diameter.

AIM: To investigate the hypothesis that lung cancer screening allows for earlier identification of ascending thoracic aortic aneurysms (aTAAs) and that growth rates for aTAAs are greatest at larger sizes. MATERIALS AND METHODS: This single referral centre retrospective study manually gathered computed tomography (CT) data from 732 patients presenting from July 2002 to August 2022. Five hundred and seventeen patients with aTAA >39 mm were identified to compare presenting diameter by year of presentation. Four hundred and thirty-two patients had CT examinations >3 months apart, allowing for growth analysis. Patients were separated by initial examination date (before or after 12/31/2013) for presenting size comparison. Patients were then divided into five groups based on aTAA diameter for growth rate analysis. RESULTS: At identification, patients had a median aTAA diameter of 44 mm (IQR 41-47 mm). Patients with aTAAs identified prior to December 2013 (n=129) had an average aTAA diameter 1.7 mm larger than those identified later (n=388; p=0.003). The growth analysis showed an average growth rate of 0.1 mm/year (p<0.001) across the entire cohort. Patients with an aTAA diameter of ≥55 mm (n=12) grew the fastest at 1.9 mm/year (p<0.001). In the <40 mm group (n=43), the aTAAs expanded at 0.2 mm/year, faster than the 0.1 mm/year of the slowest expanding 45-49 mm group (n=130; p=0.04). CONCLUSION: aTAA size at discovery was larger before lung cancer screening guidelines took effect in December 2013. The largest aTAAs expanded fastest, but growth rates were slowest in the medium-sized 45-49 mm diameter group.

Managing asthma in adolescents and adults 2020 asthma guideline update From the National Asthma Education and Prevention Program

Asthma is a major public health problem worldwide and is associated with excess morbidity, mortality, and economic costs associated with lost productivity. The National Asthma Education and Prevention Program has released the 2020 Asthma Guideline Update with updated evidence-based recommendations for treatment of patients with asthma. To report updated recommendations for 6 topics for clinical management of adolescents and adults with asthma: (1) intermittent inhaled corticosteroids (ICSs); (2) add-on long-acting muscarinic antagonists; (3) fractional exhaled nitric oxide; (4) indoor allergen mitigation; (5) immunotherapy; and (6) bronchial thermoplasty. The National Heart, Lung, and Blood Advisory Council chose 6 topics to update the 2007 asthma guidelines based on results from a 2014 needs assessment. The Agency for Healthcare Research and Quality conducted systematic reviews of these 6 topics based on literature searches up to March-April 2017. Reviews were updated through October 2018 and used by an expert panel (n = 19) that included asthma content experts, primary care clinicians, dissemination and implementation experts, and health policy experts to develop 19 new recommendations using the GRADE method. The 17 recommendations for individuals aged 12 years or older are reported in this Special Communication. From 20 572 identified references, 475 were included in the 6 systematic reviews to form the evidence basis for these recommendations. Compared with the 2007 guideline, there was no recommended change in step 1 (intermittent asthma) therapy (as-needed short-acting ß2-agonists [SABAs] for rescue therapy). In step 2 (mild persistent asthma), either daily low-dose ICS plus as-needed SABA therapy or as-needed concomitant ICS and SABA therapy are recommended. Formoterol in combination with an ICS in a single inhaler (single maintenance and reliever therapy) is recommended as the preferred therapy for moderate persistent asthma in step 3 (low-dose ICS-formoterol therapy) and step 4 (medium-dose ICS-formoterol therapy) for both daily and as-needed therapy. A short-term increase in the ICS dose alone for worsening of asthma symptoms is not recommended. Add-on long-acting muscarinic antagonists are recommended in individuals whose asthma is not controlled by ICS-formoterol therapy for step 5 (moderate-severe persistent asthma). Fractional exhaled nitric oxide testing is recommended to assist in diagnosis and monitoring of symptoms, but not alone to diagnose or monitor asthma. Allergen mitigation is recommended only in individuals with exposure and relevant sensitivity or symptoms. When used, allergen mitigation should be allergen specific and include multiple allergen-specific mitigation strategies. Subcutaneous immunotherapy is recommended as an adjunct to standard pharmacotherapy for individuals with symptoms and sensitization to specific allergens. Sublingual immunotherapy is not recommended specifically for asthma. Bronchial thermoplasty is not recommended as part of standard care; if used, it should be part of an ongoing research effort. Asthma is a common disease with substantial human and economic costs globally. Although there is no cure or established means of prevention, effective treatment is available. Use of the recommendations in the 2020 Asthma Guideline Update should improve the health of individuals with asthma.

A pragmatic randomized trial comparing tablet computer informed consent to traditional paper-based methods for an osteoporosis study.

OBJECTIVE: Methods to improve informed consent efficiency and effectiveness are needed for pragmatic clinical trials. We compared informed consent using a tablet computer to a paper approach to assess comprehension and satisfaction of patients and clinic staff for a future osteoporosis clinical trial. METHODS: Nine community-based practices identified and recruited patients to compare the informed consent processes (tablet vs. paper) in a mock osteoporosis clinical trial. The tablet informed consent included an animation summarizing the trial, complete informed consent document, and questions to assess and reinforce comprehension of the study. Participants were women age ≥55 years with ≥1 year of alendronate use. We surveyed participants to assess comprehension and satisfaction and office staff for satisfaction and perceived time demands. RESULTS: The nine practices enrolled 33 participants. There was not a significant difference in comprehension between the tablet vs. paper informed consent [mean (SD) tablet: 12.2 (1.0) vs. paper: 11.4 (1.7)]. Office staff preferred the tablet to the paper informed consent for identifying potential study participants (two-sided t-test p = 0.02) despite an increased perceived time spent to complete the tablet process [tablet: 28.3 min (SD 16.3) vs. paper: 19.0 min (SD 6.9); p = 0.08]. CONCLUSIONS: Although, there were no significant differences in participant satisfaction and comprehension with the tablet informed consent compared to a paper informed consent, patients and office staff trended towards greater satisfaction with the tablet informed consent. Larger studies are needed to further evaluate the utility of electronic informed consent in pragmatic clinical trials.

Tc-99m MDP uptake in soft tissue extraskeletal metastasis from osteogenic sarcoma.

A bone scan in a patient with proved osteogenic sarcoma of the tibia showed intense focal uptake in the gluteal region on the side of his cancer. This was proved to be a metastasis in the muscle.

Three-dimensional quantitative analysis of scintigraphic tomographic images after elastic transformation to a template.

The diagnostic information in scintigraphic images is generally not contained in specific morphological image attributes, but in the regional distribution of count rate densities across the organ volumes. In a subclass of scintigraphic images, the evaluation is actually based on a dual comparison.

Pulmonary SPECT imaging and the stripe sign.

A patient with high clinical suspicion for pulmonary embolism underwent a diagnostic scintigraphic ventilation/perfusion scan. The planar images revealed an unmatched perfusion defect with a stripe sign in the right middle lobe. A stripe sign is the appearance of normally perfused tissue between the defect and the pleural surface suggesting a nonpleural-based abnormality. SPECT images acquired in the same study period, however, failed to demonstrate normally perfused tissue between the defect and the pleural surface. Previous studies have compared planar ventilation/perfusion studies with stripe sign perfusion defects to pulmonary angiography. The results suggest that stripe sign perfusion defects are generally not due to emboli. However, planar imaging is projectional and may miss pleural contact in some perfusion lesions depending on the projection. In the absence of SPECT data, the significance of the stripe sign may need to be reassessed.

Induction of ornithine decarboxylase activity in mouse B lymphocytes.

We have examined the role in B cell activation of ornithine decarboxylase (ODC), the labile rate-limiting enzyme in the synthesis of polyamines thought to be required for S phase entry in all cells. When small resting mouse splenic B cells were stimulated with the mitogenic agents phorbol myristate acetate (PMA) plus ionomycin (lo), LPS or the B cell specific agent F(ab')2 anti-lg, ODC activity was greatly increased. ODC activity in small dense B cells remained near baseline levels for the first 6 h after treatment with LPS, but then increased approximately 150-fold in the next 18 h. When purified B cells were not separated by cell density, ODC activity was 30-fold greater at baseline and rose earlier after LPS stimulation, reaching a level about three times that of LPS-stimulated small, dense B cells at 24 h, implying that large (preactivated) B cells have much greater ODC responses than small, dense B cells. ODC activity, like S phase entry, could also be induced in small, dense B cells by PMA and lo but failed to respond to either agent alone. ODC levels rose transiently by approximately 40-fold between 2 and 6 h following stimulation of small B cells with F(ab')2 anti-lg, then declined to baseline. Whole anti-lg did not stimulate ODC activity and also blocked the F(ab')2 anti-lg mediated increase in ODC activity, just as it produced the expected inhibition of thymidine incorporation and cellular progression into S phase.(ABSTRACT TRUNCATED AT 250 WORDS)

Time dependence of lung mechanics in preterm lambs.

The passive exhalation flow-volume plots of preterm lambs exhibit curvature. To explain this curvature, we proposed two mathematical models that could predict the measured passive exhalation flow-volume data well. One model takes into account the flow and volume dependence of resistance and compliance. The second model emphasizes the time dependence of lung mechanics and considers the respiratory system viscoelastic properties and the analogy of the lung to two electronic resistor-capacitor circuits connected in parallel. We attempted to determine which of the two models is more valid by analyzing passive exhalation flow-volume data that were obtained while briefly obstructing flow midway through deflation. In 14 preterm lambs (130 d gestation), the flow of exhaled gas increased from 76 +/- 35 mL/s when measured just before obstruction to 90 +/- 30 mL/s when measured immediately after release of the obstruction (p less than 0.0001). This finding suggests that a time-dependent phenomenon was taking place during obstruction and is inconsistent with the model based upon the flow and volume dependence of resistance and compliance. We made similar measurements in four near-term (143-146 d gestation) and four full-term lambs (9-12 d of age). Their flow-volume curves were relatively linear, and they showed no increases in flow after removal of the obstruction. The results of this study strongly suggest that time-dependent phenomena caused the curvilinearity in the passive exhalation flow-volume plots of preterm lambs. We suspect that the time-dependent phenomena is associated with the premature lung and with parenchymal lung disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Practice style differences between family physicians and internists.

BACKGROUND: Because an estimated 70 percent of all medical care expenditures are generated by physicians, evaluation of specialty practice styles is essential to learn what changes in policies governing physician training, service delivery, and patterns of medical practice would promote cost containment. METHODS: We examined the 1981 and 1985 National Ambulatory Medical Care Survey for seven primary care diagnoses to compare practice style differences between family physicians and internists and to look for changes in family physicians' practice styles between 1981 and 1985. RESULTS: Family physicians referred fewer patients in 1985 and spent 3 to 10.5 minutes less per patient encounter than internists. Clinical laboratory testing, electrocardiogram (ECG) ordering, and radiographic examinations differed significantly between the two groups in 1981 and 1985 for some diagnoses. In 1981, family physicians did Papanicolaou smears 2.2 times more often than internists during general medical examinations; however, in 1985, there was no difference. Between 1981 and 1985, family physicians ordered significantly more laboratory tests and ECGs for some diagnoses but had no change in the number of radiographs ordered or referrals. For six diagnoses, they spent more time with a patient encounter in 1985 than in 1981. CONCLUSIONS: Family physicians and internists appear to be more alike in practice style, but significant differences remain. These differences, as well as changing practice styles of family physicians, have implications for training and health care resource distribution.

Measuring health: guidelines for reliability assessment.

In the area of health measurement, few guidelines exist for the health professional interested in understanding the concept of reliability. Yet, often there is a need to construct, modify, or select a reliable instrument that will satisfy a particular research or clinical need. This article reviews the concept of reliability and presents a few of the more common techniques used to calculate the reliability of health assessment instruments. Practical guidelines for questionnaire construction and administration are also discussed.

Qualitative and quantitative methods for the assessment of clinical preceptors.

The improvement of clinical teaching skills has consistently been an important focus of faculty development in family medicine. Successful faculty development programs depend on an understanding of the components of clinical teaching and a profile of the strengths and weaknesses of each faculty member with respect to these components. In this study a system was developed to identify and measure specific faculty characteristics of inpatient preceptors. Complementary quantitative and qualitative approaches were employed. An analysis and comparison of the two approaches suggest that the measures result in a similar ranking of faculty, but that the qualitative approach identifies individual faculty strengths and weaknesses, which are more useful for providing feedback to stimulate and guide change.

Passive deflation time constant of 7-week-old rabbits.

The purpose of our study was to determine the effects of insufflation time (TI) and of tidal volume (VT) on the passive deflation time constant (tau) of juvenile rabbits. We sedated and paralyzed nine 7-wk-old New Zealand rabbits (wt 1.2 +/- 0.2 SD kg) and placed them on a time-cycled, pressure-limited mechanical ventilator. Measurements of tau and dynamic compliance of the respiratory system were made at nine ventilator settings. TI was adjusted to 0.2, 0.4, and 0.6 s and VT was adjusted to 10, 15, and 20 mL so that the effects of TI and VT on tau could be determined independently. Respiratory system quasi-static and static compliances were also measured and served as a basis for discussing the physiologic explanations for the effects of TI and VT on tau. In general, increases in TI resulted in increases in tau and increases in VT also resulted in increases in tau. Increasing TI from 0.2 to 0.6 s plus increasing VI from 10 to 20 mL resulted in an increase in tau from 0.220 +/- 0.007 to 0.282 +/- 0.010 s (mean +/- SEM) (p less than 0.05, student Newman-Kuels), which is a 28% increase. At a VT of 10 mL, dynamic compliance increased from 1.95 +/- 0.10 to 2.14 +/- 0.10 mL/cm H2O (p less than 0.05) when TI was increased from 0.2 to 0.6 s; however, dynamic compliance decreased 19% as VT was increased from 10 to 20 mL.(ABSTRACT TRUNCATED AT 250 WORDS)

Geriatric assessment in the office setting.

Attention to functional limitations must be incorporated into the routine care of the elderly. Several brief, validated functional assessment instruments are now available for office use. Routine screening of the elderly population typically uncovers unknown concerns in one third to one half of patients, even if those patients are well known to their physician. Functional assessment instruments have been developed with specific site and populations in mind. Therefore, physicians should evaluate which instrument best matches the population to be tested. Functional measures should be viewed as an adjunct to improving care, not as a stand-alone diagnostic test.

Biofragmentable bowel anastomosis ring: comparative efficacy studies in dogs.

Three studies were conducted in a total of 178 dogs to determine the efficacy of a biofragmentable bowel anastomosis ring (BAR) composed of polyglycolic acid and 12.5% barium sulfate. Wound strength and healing of BAR, suture, and staple colonic anastomoses were compared for intervals of up to 1 year. The effect of systemic steroid treatment and BAR size on anastomotic wound strength and healing was also studied. The BARs fragmented at a mean time of 15.06 days postoperatively and were passed in the feces without injury. Wound strength was determined by measurements of the pressure required to burst the anastomosed colonic segment and measurements of the tension required to break 10 mm wide longitudinal strips of the anastomosed segment. The studies demonstrated that wound strength had progressed to a point where continued mechanical support (with sutures or staples) was no longer required by 14 days in both nontreated and steroid-treated dogs. Gross healing evaluations at 21 days and beyond showed no differences due to anastomotic method. Microscopic evaluations suggested that residual granulation tissue was less at the sites of BAR asastomoses than at sites of suture or staple anastomoses at the 1-year interval, suggesting that healing may be better with BAR than with standard methods of colon anastomosis.

Initial clinical experience with a biofragmentable ring for sutureless bowel anastomosis.

Twenty-seven patients have had bowel anastomoses with a biofragmentable ring for sutureless bowel anastomosis. There were no complications associated with the anastomotic technique. One patient developed an ischemic stricture on the proximal side of the anastomosis due to compromised circulation. There was no leakage. Technical factors regarding the BAR anastomosis are described. A properly placed purse-string suture is of primary importance. Advantages appear to be a more rapid and easy anastomosis with better healing.

Apparatus for long-term ventricular access in the awake canine.

An apparatus is described that permits lateral ventricular cerebrospinal fluid (CSF) to be sampled or an infusion to be performed into the ventricular system in the awake canine. The device has been used in 25 dogs. CSF was sampled, and experiments involving infusions into the lateral ventricle were performed over a 6- to 24-mo period. The maximum frequency of ventricular cannulation using the apparatus was once per week. Complications occurred in 10 dogs, all of which were successfully treated, permitting experiments to continue. Three fatal complications included meningitis in one animal at 24 mo and seizures in two animals, causing death at 12 and 18 mo. Administration of peptides, bombesin, and somatostatin into the ventricular system was followed by prompt rises in bombesin and somatostatin radioimmunoactivity in the CSF. There were no parallel increases of these peptides in the peripheral blood levels up to 2 h after infusion. Peptides of this molecular weight infused with this apparatus do not seem to leak into peripheral blood. The apparatus permits repeated ventricular cannulation in the awake canine for sampling of CSF and administration of biological substances to determine specific central nervous system action.

A biofragmentable ring for sutureless bowel anastomosis. An experimental study.

A biofragmentable bowel anastomosis ring (BAR) for sutureless intestinal anastomosis is described with the laboratory results comparing the BAR to sutured and stapled anastomoses. There was equivalent healing with all three methods of anastomosis. However, "burst" pressure was highest at day zero and overall necrosis was least with the BAR. By virtue of these findings and being sutureless, it is hoped that the limits of safe bowel anastomosis can be extended.