Nursing home-acquired pneumonia (NHAP) was described in 1978, but only in 2005 it has been proposed as part of a new category (health care-associated pneumonia) distinct from community- or ...hospital-acquired infections. However, limited clinical data exist to validate this proposal.
To compare characteristics and outcome of patients hospitalised for pneumonia and coming from private residence or nursing home.
Post-hoc analysis of the prospective phase of the FASTCAP study, performed to evaluate the impact of the Recommendations issued by the Italian Federation of Internal Medicine (FADOI) in 2002 on the management of hospitalised community-acquired pneumonia (CAP).
The study examined 1,219 patients coming from private residence, and 179 with NHAP. Failures of therapy were significantly more frequent in patients with NHAP (35.8% vs 24.9%; Odds Ratio 1.48; 95% confidence interval 1.05-2.09). Mortality was higher in patients coming from nursing home (24.0% vs 9.8%; OR 2.59; 95% CI 1.72-3.90). Antibiotic treatment was more frequently performed as monotherapy in case of NHAP.
At the time of FASTCAP, NHAP was included in the category of CAP, and coherently, treatment of NHAP was not more aggressive if compared to community-acquired infections. However, our results confirm that NHAP is at increased risk for worst outcome, and probably worth considering for specific therapeutic strategies. Future studies are needed to better assess the microbiology of NHAP, and to evaluate if specific treatments, as those recommended by recent guidelines, may improve the outcome for these high-risk patients.
Two analytical models are proposed to describe two different mechanisms of lava tubes formation.
A first model is introduced to describe the development of a solid crust in the central region of the ...channel, and the formation of a tube when crust widens until it reaches the leve\'es. The Newtonian assumption is considered and the steady state Navier- Stokes equation in a rectangular conduit is solved. A constant heat flux density assigned at the upper flow surface resumes the combined effects of two thermal processes: radiation and convection into the atmosphere. Advective terms are also included, by the introduction of velocity into the expression of temperature. Velocity is calculated as an average value over the channel width, so that lateral variations of temperature are neglected. As long as the upper flow surface cools, a solid layer develops, described as a plastic body, having a resistance to shear deformation. If the applied shear stress exceeds this resistance, crust breaks, otherwise, solid fragments present at the flow surface can weld together forming a continuous roof, as it happens in the sidewall flow regions.
Variations of channel width, ground slope and effusion rate are analyzed, as
parameters that strongly affect the shear stress values. Crust growing is favored when the channel widens, and tube formation is possible when the ground slope or the effusion rate reduce.
A comparison of results is successfully made with data obtained from the analysis of pictures of actual flows.
The second model describes the formation of a stable, well defined crust along both channel sides, their growing towards the center and their welding to form the tube roof. The fluid motion is described as in the model above. Thermal budget takes into account conduction into the atmosphere, and advection is included considering the velocity depending both on depth and channel width. The solidified crust has a non uniform thickness along the channel width. Stresses acting on the crust are calculated using the equations of the elastic thin plate, pinned at its ends. The model allows to calculate the distance where crust thickness is able to resist the drag of the underlying fluid and to sustain its weight by itself, and the level of the fluid can lower below the tube roof.
Viscosity and thermal conductivity have been experimentally investigated through the use of a rotational viscosimeter. Analyzing samples coming from Mount Etna (2002) the following results have been obtained: the fluid is Newtonian and the thermal conductivity is constant in a range of temperature above the liquidus. For lower temperature, the fluid becomes non homogeneous, and the used experimental techniques are not able to detect any properties, because measurements are not reproducible.
Though venous thromboembolism (VTE) frequently occurs in non-surgical setting, epidemiology and risk factors for VTE in unselected medical inpatients have not been extensively studied, and ...uncertainties remain about the prophylactic strategy in these patients.
In a prospective, observational, multicenter study we aimed to contemporarily assess the epidemiology of symptomatic VTE in consecutive patients hospitalized in Internal Medicine, to evaluate the impact of potential risk factors, and the attitude of internists towards thromboprophylaxis. A total of 4,846 patients were included, during the period March-September 2006.
Symptomatic VTE was registered in 177 (3.65%) patients; of these, 26 cases (0.55%) occurred with onset of symptoms ≥ 48
hours after admission (“hospital-acquired” events, primary study end-point). Previous VTE and bed resting were significantly associated with venous thromboembolism, while a trend for increased risk was documented in cancer patients. During hospital stay antithrombotic prophylaxis was globally administered in 41.6% of patients, and in 58.4% of those for which prophylaxis was recommended according to 2004 guidelines by the American College of Chest Physicians. The choice of administering tromboprophylaxis appeared qualitatively adherent to indications from randomized trials and international guidelines, and bed rest was the strongest determinant of the use of prophylaxis.
Data from our real-world study confirm that VTE is a quite common finding in patients admitted to Internal Medicine departments, and recommended tromboprophylaxis is still underused, in particular in some patients groups. Further efforts are needed to better define the risk profile and to optimize prophylaxis in the heterogeneous setting of medical patients.
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