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61.
62.
Dan Greitz 《Child's nervous system》2007,23(5):487-489
Objective This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively
absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims
to briefly describe the new hydrodynamic concept of hydrocephalus and the rationale for endoscopic third ventriculostomy (ETV)
in communicating hydrocephalus.
Critique The bulk flow theory has proven incapable of explaining the pivotal mechanisms behind communicating hydrocephalus. Thus, the
theory is unable to explain why the ventricles enlarge, why the CSF pressure remains normal and why some patients improve
after ETV.
Hydrodynamic concept of hydrocephalus Communicating hydrocephalus is caused by decreased intracranial compliance increasing the systolic pressure transmission into
the brain parenchyma. The increased systolic pressure in the brain distends the brain towards the skull and simultaneously
compresses the periventricular region of the brain against the ventricles. The final result is the predominant enlargement
of the ventricles and narrowing of the subarachnoid space. The ETV reduces the increased systolic pressure in the brain simply
by venting ventricular CSF through the stoma. The patent aqueduct in communicating hydrocephalus is too narrow to vent the
CSF sufficiently. 相似文献
63.
Christian Waydhas Dieter Nast-Kolb Steffen Ruchholtz 《European journal of trauma and emergency surgery》2007,33(2):170-175
Abstract
Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation
to detect pelvic ring fractures and to identify those with severe bleeding.
Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims
with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the
iliac wings.
Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical
instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not
be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity
of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating
blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity
97.0%, positive predictive value 38.1%, negative predictive value 99.9%).
Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic
ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most
of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture
as being the source of bleeding quite unlikely. 相似文献
64.
Background
Reports on childhood cancer survivors estimated cumulative probability of developing secondary neoplasms vary from 3,3% to 25% at 25 years from diagnosis, and the risk of developing another cancer to several times greater than in the general population. 相似文献65.
66.
Gerard J Molloy Derek W Johnston Chuan Gao Miles D Witham Joan M Gray Ishbel S Argo Allan D Struthers Marion E T McMurdo 《European journal of cardiovascular prevention and rehabilitation》2006,13(3):381-387
BACKGROUND: The impact of exercise programmes for heart failure on those close to the patient is largely unknown. We examined the effect of a hospital and home-based exercise intervention on burden, anxiety and depression of informal caregivers. DESIGN: The study was a randomized, controlled trial. Heart failure patients were randomized to a seated 12-week hospital-based exercise programme. Caregiver measures were gathered at baseline, 3 months later and 6 months following baseline. METHODS: Sixty caregivers (mean age 63.4 years, 65% female) of heart failure patients (n = 82, mean age 80.5 years, 44% female) participating in a trial of an exercise intervention were recruited. Caregiver burden, anxiety and depression were assessed. RESULTS: There were no differences in caregiver burden, depression or anxiety between the two groups of caregivers at baseline (caregiver burden, patient control 33.1 versus patient exercise 34.1; anxiety 4.1 versus 5.5; depression 2.8 versus 3.8). At 3 months there were no differences between caregivers in the two groups on outcomes. At 6-month follow-up caregivers of heart failure patients in the exercise group had burden scores that were significantly worse than the control group. There were no differences between the carers of exercise and control groups in anxiety and depression. Levels of anxiety and depression in the entire carer sample were marginally higher than reference values in a healthy non-clinical sample. CONCLUSION: The present exercise interventions for frail older patients did not benefit caregivers and was associated with an increase in caregiver burden. We suggest that future exercise interventions for heart failure patients should actively incorporate informal caregivers into research designs. 相似文献
67.
Birgitta Malmberg Göran Kecklund Björn Karlson Roger Persson Per Flisberg Palle Ørbaek 《BMC health services research》2010,10(1):239
Background
It is well known that physicians' night-call duty may cause impaired performance and adverse effects on subjective health, but there is limited knowledge about effects on sleep duration and recovery time. In recent years occupational stress and impaired well-being among anaesthesiologists have been frequently reported for in the scientific literature. Given their main focus on handling patients with life-threatening conditions, when on call, one might expect sleep and recovery to be negatively affected by work, especially in this specialist group. The aim of the present study was to examine whether a 16-hour night-call schedule allowed for sufficient recovery in anaesthesiologists compared with other physician specialists handling less life-threatening conditions, when on call. 相似文献68.
David Berrigan Linda W Pickle Jennifer Dill 《International journal of health geographics》2010,9(1):20
Background
Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT) or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey. 相似文献69.
Sebastiana Z. Kalula G. H. Swingler A. A. Sayer M. Badri M. Ferreira 《The journal of nutrition, health & aging》2010,14(4):319-323
Objective
To test the effects of the use of a collapsible, portable chair (chair B), as opposed to a ‘standard’ chair (chair A), on the outcome of the timed “Up and Go” (TUG) test. 相似文献70.