4,138 research outputs found
Incidence, severity and prognosis associated with hypernatremia in dogs and cats.
BackgroundHypernatremia has been associated with substantial morbidity and death in human patients. The incidence and importance of hypernatremia in dogs and cats has not been determined.Hypothesis/objectivesTo describe the incidence of and prognosis associated with hypernatremia in dogs and cats at a university teaching hospital.AnimalsA total of 16,691 dogs and 4,211 cats with measured blood or serum sodium concentration.MethodsRetrospective study. Medical records of animals with a blood or serum sodium concentration measured during a 60-month period were reviewed to determine the severity of hypernatremia and its associated case fatality rate. Cases with moderate (11-15 mmol/L above the reference range) or severe hypernatremia (≥16 mmol/L above the reference range) were further reviewed.ResultsA total of 957 dogs (5.7%) and 338 cats (8.0%) were diagnosed with hypernatremia. Case fatality rates of dogs and cats with hypernatremia was 20.6 and 28.1%, respectively compared to 4.4 and 4.5% with a normal blood or serum sodium concentration (P < .0001). The magnitude of hypernatremia was linearly associated with a higher case fatality rate (P < .0001). Hypernatremia was associated with a higher case fatality rate than hyponatremia. Among the animals with moderate or severe hypernatremia, 50% of dogs and 38.5% of cats presented with community-acquired hypernatremia, and 50% of dogs and 61.5% of cats developed hospital-acquired hypernatremia.Conclusions and clinical importanceHypernatremia was found infrequently in this population but was associated with increased case fatality rates in dogs and cats. Presence and severity of hypernatremia might be useful as a prognostic indicator
Diagnostic yield of cytologic analysis of pericardial effusion in dogs.
BackgroundPericardial effusion cytology is believed by many to be of limited value, yet few studies have evaluated its diagnostic utility.ObjectivesTo determine the diagnostic utility of cytologic analysis of pericardial effusion in dogs and to determine if consideration of additional data could improve the diagnostic yield.AnimalsTwo hundred and fifty-nine dogs with cytologic analysis of pericardial effusion performed between April 1990 and June 2012.MethodsElectronic medical records from a university teaching hospital were retrospectively reviewed; signalment, complete blood count, serum biochemistry, cytologic analysis of pericardial effusion, and echocardiographic data were recorded. Cytology was classified as diagnostic (infectious or neoplastic) or nondiagnostic (hemorrhagic or other) and groups were compared with multiple Student's t-tests.ResultsCytology was grouped as nondiagnostic (92.3%) or diagnostic (7.7%) and characterized as hemorrhagic (90%), neoplastic (4.6%), infectious (3.1%), or other (2.3%). Overall cytologic analysis of pericardial effusion diagnostic utility was 7.7% and increased to 20.3% if the effusion hematocrit (HCT) <10%; echocardiographic evidence of a mass did not result in a significant increase in the diagnostic utility.Conclusions and clinical importanceThe diagnostic utility of cytologic analysis of canine pericardial effusion is variable depending on the underlying etiology. In this group of dogs, the diagnostic yield of cytologic analysis was greater for pericardial effusion samples in which the HCT was less than 10%
Extremely asymmetrical scattering in gratings with varying mean structural parameters
Extremely asymmetrical scattering (EAS) is an unusual type of Bragg
scattering in slanted periodic gratings with the scattered wave (the +1
diffracted order) propagating parallel to the grating boundaries. Here, a
unique and strong sensitivity of EAS to small stepwise variations of mean
structural parameters at the grating boundaries is predicted theoretically (by
means of approximate and rigorous analyses) for bulk TE electromagnetic waves
and slab optical modes of arbitrary polarization in holographic (for bulk
waves) and corrugation (for slab modes) gratings. The predicted effects are
explained using one of the main physical reasons for EAS--the diffractional
divergence of the scattered wave (similar to divergence of a laser beam). The
approximate method of analysis is based on this understanding of the role of
the divergence of the scattered wave, while the rigorous analysis uses the
enhanced T-matrix algorithm. The effect of small and large stepwise variations
of the mean permittivity at the grating boundaries is analysed. Two distinctly
different and unusual patterns of EAS are predicted in the cases of wide and
narrow (compared to a critical width) gratings. Comparison between the
approximate and rigorous theories is carried out.Comment: 16 pages, 5 figure
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