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Pressure Readings (pressure + reading)
Kinds of Pressure Readings Selected AbstractsA Comparison of Web Sites Used to Manage and Present Home Blood Pressure ReadingsJOURNAL OF CLINICAL HYPERTENSION, Issue 6 2010Birju Patel BS J Clin Hypertens (Greenwich). 2010;12:389,395. ©2010 Wiley Periodicals, Inc. Home blood pressure (HBP) monitoring is now recommended as a routine component of blood pressure management in patients with known or suspected hypertension. Over the last few years, a large number of Web sites, commonly termed Personal Health Records, have been developed so that patients can manage and present HBP readings. The objective of this report is to describe and compare these Web sites. A list of 33 desirable Web site features, organized into 4 categories, was developed. Between June and August of 2009, a total of 60 Web sites was identified, of which 20 were free or free to try. Each of the 20 Web sites displayed HBP readings in tabular and graphical formats, most offered an option to print results in tabular (70%) and graphical (70%) form, and many (47%) could download HBP data from Microsoft HealthVault. In contrast, none of the Web sites directly linked with common electronic medical records. Overall, Web sites offered between 41% and 77% of the 33 features considered desirable. In conclusion, there is considerable variation in available features on Web sites used to manage HBP data. Information presented in this report should be useful to physicians and patients in selecting a Web site for managing and presenting HBP readings and ultimately improving blood pressure control. [source] Tumor interstitial fluid pressure may regulate angiogenic factors in osteosarcomaJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 11 2008Saminathan S. Nathan Abstract We have previously shown that osteosarcomas (OS) have states of increased interstitial fluid pressure (IFP), which correlate with increased proliferation and chemosensitivity. In this study, we hypothesized that constitutively raised IFP in OS regulates angiogenesis. Sixteen patients with the clinical diagnosis of OS underwent blood flow and IFP readings by the wick-in-needle method at the time and location of open biopsy. Vascularity was determined by capillary density in the biopsy specimens. We performed digital image analysis of immunohistochemical staining for CD31, VEGF-A, VEGF-C, and TPA on paraffin-embedded tissue blocks of the biopsy samples. Clinical results were validated in a pressurized cell culture system. Interstitial fluid pressures in the tumors (mean 33.5,±,SD 17.2 mmHg) were significantly higher (p,=,0.00001) than that in normal tissue (2.9,±,5.7 mmHg). Pressure readings were significantly higher in low vascularity tumors compared to high vascularity tumors (p,<,0.001). In the OS cell lines, growth in a pressurized environment was associated with VEGF-A downregulation, VEGF-C upregulation, and TPA upregulation. The reverse was seen in the OB cell line. Growth in the HUVEC cell line was not significantly inhibited in a pressurized environment. Immunohistochemical assessment for VEGF-A (p,=,0.01), VEGF-C (p,=,0.008), and TPA (p,=,0.0001) translation were consistent with the findings on PCR. Our data suggests that some molecules in angiogenesis are regulated by changes in IFP. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1520,1525, 2008 [source] AER lecture: Some reflections on corneal thicknessACTA OPHTHALMOLOGICA, Issue 2007N EHLERS The corneal thickness as an object for studies was recognized in the renaissance. A value of 1 mm, representing the maximally swollen human cornea, was reported. Optical in vivo measurements were done by Blix in 1880 reporting a thickness of about 0.5 mm, the value that we today know is correct. Blix lived in "the golden age of physiologic optics". His interest was the contribution of the cornea to the optical refraction of the eye, and was thus the distance between the anterior and the posterior surface rather than the thickness of the cornea as such. A biomechanical interest in corneal thickness was initiated by the studies of tonometry, in particular Hans Goldmann's development of applanation tonometry. He predicted correctly that corneal thickness would influence the estimated pressure reading. Another physiological aspect of the cornea is its transparency. Earlier explanations by equal refractive index was revolutionized by the interference theory by David Maurice. Optical transparency required a regular fiber pattern, and thus a stabilized thickness and stromal hydration. This led to extensive interest in the permeability of the limiting layers, in particular the transport of fluid across the endothelium. The physiological concepts required a regulated or stabilized thickness. The thickness as such became interesting. The human cornea is thinner in the center than more peripherally and the central, presumably regulated central thickness (CCT) became a biometric and clinical study object. The exact individual value became of interest. Several optical and later ultrasonic principles were presented. Questions addressed were: Is CCT a life-long, age independent characteristics. Is CCT diagnostic for certain disease conditions (e.g. Macular dystrophy of Groenouw). Is CCT a useful clinical parameter to follow disease processes (e.g. progression in keratoconus or acute changes in graft rejections). Today refractive surgery has revived the interest in biomechanical and optical properties of the cornea. Modern computer technology allows for a description of the "thickness profile" of the entire cornea. This gives us access to an overwhelming amount of data, and reopen many issues of the past. We must realize, however, that what we see is the pendulum swinging back to the problems of the last century. The machinery is smarter but many of the basic questions remain to be solved. [source] Instrumental pressure observations and atmospheric circulation from the 17th and 18th centuries: London and ParisINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 3 2001V.C. Slonosky Abstract Daily pressure observations recorded by William Derham (1657,1735) at Upminster, Essex (near London), from 1697 to 1706 and 1708 have been corrected, converted to modern units and the Gregorian calendar, and adjusted for homogeneity. These pressure readings have been compared with previously published contemporary observations from Paris, and the two sets of early instrumental data used to calculate a daily series of the pressure difference between Paris and London. Frequency analysis of the daily series reveals that reversals of the south,north pressure gradient and easterly winds were more common from 1697 to 1708 than during the 1990s. Monthly mean values of Paris,London pressure differences have been compared with previously published monthly mean reconstructed surface pressure maps and to a reconstructed North Atlantic Oscillation (NAO) index. There is a good agreement between the strength and direction of monthly mean flow between London and Paris estimated from the circulation maps and the sign and magnitude of the Paris,London westerly flow index, but the correlation between the Paris,London index, known to be a good proxy for European zonal circulation, and the reconstructed NAO index, is low (0.2). Correlations between the monthly mean Paris,London zonal circulation index and central England temperatures suggest a strong relationship during winter and late summer from 1697 to 1708. The meticulous daily instrumental observations and the monthly and seasonal climate descriptions of Derham, his collection of instrumental observations and climatic descriptions from contemporary observers throughout Europe, and his early theories on the causes of climate change make his publications a valuable source of information for studies on climate during the early instrumental period. It is hoped that more of Derham's papers related to weather and climate may eventually come to light. Copyright © 2001 Royal Meteorological Society. [source] Prospective Surveillance of Hypertension in FirefightersJOURNAL OF CLINICAL HYPERTENSION, Issue 5 2003Elpidoforos S. Soteriades MD The authors evaluated blood pressure and antihypertensive medication use in 334 firefighters in an occupational medical surveillance program. Firefighters received written summaries of their examination results, including blood pressures, and were encouraged to see their personal physicians for any abnormal results. The mean age of the participants was 39 years, and the vast majority were men (n=330). The prevalence of hypertension was 20% at baseline (1996), 23% in 1998, and 23% in 2000. Among firefighters with high blood pressure readings, only 17%, 25%, and 22% were taking antihypertensive medications at the baseline, 1998, and 2000 examinations, respectively. Medical surveillance was effective in detecting hypertension in firefighters; however, after 4 years of follow-up, only 42% of hypertensives were receiving treatment with medications, including only 22% of firefighters with hypertensive readings. Overall, 74% of hypertensives were not adequately controlled. Possible reasons for low treatment rates may be the inadequate recognition among primary care physicians that mild hypertension is a significant risk factor for cardiovascular disease. [source] The effect of clothes on sphygmomanometric blood pressure measurement in hypertensive patientsJOURNAL OF CLINICAL NURSING, Issue 13-14 2010Rukiye Pinar Aims., To test whether there is any difference between blood pressure readings with patients wearing clothes under the manometer's cuff and not wearing clothes. Background., The few studies published on this subject have shown that blood pressure measurements give similar results whether the patients' arm is covered by clothing or not. However, it has not been clarified whether this is also true in hypertensive patients. Method., Blood pressure was measured on non-sleeved arm, sleeved arm and again on non-sleeved arm in 258 hypertensive patients using a mercury-filled column sphygmomanometer. Three nurses who were experienced and specially trained for the study performed blood pressure measurements. They were unaware of the purpose of the research. Results., Measuring blood pressure with the manometer's cuff over participant's sleeved arm did not differ significantly from non-sleeved arm measurements. Relevance to clinical practice., Sleeves have no effect on blood pressure results. Blood pressure readings taken over the sleeves will be much more practical and time saving in busy departments like emergency rooms, during disasters like earthquake where decisions have to make in minutes. Additionally, it will be time saving for general health screening surveys. Finally, it may have preferable because of hygiene concerns, patient privacy and religious beliefs. [source] Ambulatory monitoring and physical health report in Vietnam veterans with and without chronic posttraumatic stress disorderJOURNAL OF TRAUMATIC STRESS, Issue 4 2003Jean C. Beckham Abstract This study investigated the associations among PTSD, ambulatory cardiovascular monitoring, and physical health self-reports in 117 male Vietnam combat veterans (61 with PTSD and 56 without PTSD). PTSD was associated with health symptoms and number of current health conditions beyond the influence of several covariates. PTSD was associated with greater systolic blood pressure variability, and an elevated percentage of heart rate and systolic blood pressure readings above baseline. Higher mean heart rate and an elevated percentage of heart rate above baseline were associated with physical health symptoms. None of the ambulatory monitoring variables mediated the association between PTSD and physical health outcomes. Findings suggest that the interrelationships among ambulatory autonomic responses, PTSD, and physical health deserve more research attention. [source] A compliant tip reduces the peak pressure of laparoscopic graspersANZ JOURNAL OF SURGERY, Issue 7 2002Damian D. Marucci Background: Previous studies have demonstrated that high pressures are generated at the tips of laparoscopic graspers, which can cause tissue injury. This study examines the effect of a compliant edge on tip pressure. Methods: One of a pair of identical laparoscopic graspers was modified by refashioning the tip out of silicone. A thin film pressure transducer (I-scan 6900 sensor) was deployed between the jaws of the grasper and a simulated tissue (leather strap). Load and handle pressures were kept constant. Peak tip pressure readings were taken as the load orientation was increased from the perpendicular to 135° (n = 10). The data was analysed using anova and a post-hoc Duncan's multiple range test. Results: Peak tip pressures generated by the compliant tipped grasper were significantly less than those developed by the unmodified grasper, particularly at high-load orientations. Conclusion: High pressures generated at the tip of laparoscopic graspers can be reduced by altering the mechanical properties (compliance) of the tip. [source] External cephalic version induced fetal cerebral and umbilical blood flow changes are related to the amount of pressure exertedBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 5 2004Tak Yeung Leung Objective To correlate the applied pressure during external cephalic version with the changes in fetal middle cerebral arterial and umbilical arterial flow before and after the procedure. Design A prospective observational study over a two-year period. Setting External cephalic version was performed in a university hospital. Population Sixty-nine women with singleton breech-presenting pregnancy at or above 36 weeks of gestation undergoing external cephalic version. Methods During external cephalic version, the operator wore a pair of pressure-sensing gloves which had thin piezo-resistive sensors positioned on the palmar surface. During each version procedure, real-time pressure readings were recorded from all sensors, and then analysed with a computer program. The amount of pressure applied over time was presented by pressure,time integral. The pulsatility indices of both fetal middle cerebral artery and umbilical artery before and after external cephalic version were measured. The changes of pulsatility indices of both middle cerebral artery and umbilical artery were presented as a ratio of the post-external cephalic version pulsatility indices to pre-external cephalic version pulsatility indices, denoted by middle cerebral artery pulsatility index ratio and umbilical artery pulsatility index ratio, respectively. The statistical correlation between pressure,time integral and middle cerebral artery pulsatility index ratio and umbilical artery pulsatility index ratio are analysed using Pearson's correlation test. Main outcome measures Changes in pulsatility indices of fetal middle cerebral and umbilical arteries and fetal heart rate after external cephalic version. Results The overall success rate of external cephalic version was 77%. There was a significant negative correlation between pressure,time integral and both middle cerebral artery pulsatility index ratio (P= 0.001) and umbilical artery pulsatility index ratio (P= 0.012). When women were categorised according to placental site, pressure,time integral was negatively correlated with middle cerebral artery pulsatility index ratio only when the placenta was posteriorly located (P= 0.003), and with umbilical artery pulsatility index ratio only when the placenta was laterally located (P= 0.03). Conclusions The greater the force applied during external cephalic version, the greater the reduction in pulsatility indices of middle cerebral artery and umbilical artery, indicating an increase in blood flow through these arteries. The increase in cerebral blood flow after external cephalic version is more prominent when the placenta is lying posteriorly, while the increase in umbilical flow is more prominent when the placenta is lying laterally. These findings suggest that the vascular changes probably represent a direct effect of force exerted on the fetal head and the placenta. [source] | ||||||||||