Risk factors and natural history of bedside percutaneous endoscopic versus fluoroscopy-guided gastrostomy tubes in intensive care unit patients.

INTRODUCTION: There is a paucity of literature comparing patients receiving bedside placed percutaneous endoscopic gastrostomy (PEG) versus fluoroscopic-guided percutaneous gastrostomy tubes (G-tube) in an intensive care unit (ICU) setting. This study aims to investigate and compare the natural history and complications associated with PEG versus fluoroscopic G-tube placement in ICU patients. METHODS: All adult patients admitted in the ICU requiring feeding tube placement at our center from 1/1/2017 to 1/1/2022 with at least 12-month follow up were identified through retrospective chart review. Adjusting for patient comorbidities, hospital factors, and indications for enteral access, a 1-to-2 propensity score matched Cox proportional-hazards model was fitted to evaluate the treatment effect of bedside PEG tube placement versus G-tube placement on patient 1-year complication, readmission, and death rates. Major complications were defined as those requiring operative or procedural intervention. RESULTS: This study included 740 patients, with 178 bedside PEG and 562 fluoroscopic G-tube placements. The overall rate of complication was 22.3% (13% PEG, 25.2% G-tube, P = 0.003). The major complication rate was 11.2% (8.5% PEG, 12.1% G-tube, P = 0.09). Most common complications were tube dysfunction (16.7% PEG; 39.4% G-tube; P = 0.04) and dislodgement (58.3% PEG; 40.8% G-tube). After propensity score matching, G-tube recipients had significantly increased risk for all-cause (HR 2.7, 95% CI 1.56-4.87, P < 0.001) and major complications (HR 2.11, 95% CI 1.05-4.23, P = 0.035). There were no significant differences in 1-year rates of readmission (HR 0.90, 95% CI 0.58-1.38, P = 0.62) or death (HR 1.00, 95% CI 0.70-1.44, P = 0.7). CONCLUSIONS: The overall rate of complications for ICU patients requiring feeding tube in our cohort was 22.3%. ICU patients receiving fluoroscopic-guided percutaneous gastrostomy tube placement had significantly elevated risk of 1-year all-cause and major complications compared to those undergoing bedside PEG.

Uniaxial compressive properties of human lumbar 1 vertebrae loaded beyond compaction and their relationship to cortical and cancellous microstructure, size and density properties.

Lumbar 1 vertebrae are among those most commonly fracture due to osteoporosis. The strength of human vertebrae and its structural, microstructural and material determinants have been the subject of numerous studies. However, a comprehensive evaluation of properties beyond maximum load to fracture has not been available for the L1 vertebrae. The objective of this study was to document these properties in association with each other and with the geometric, density and cancellous and cortical structure properties for human L1 vertebrae. Bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), connectivity density (Conn.Dn), degree of anisotropy (DA), structure model index (SMI) and fractal dimension (FD) of the cancellous microstructure, tissue mineral density (TMD), and thickness of the cortical shell (Sh.Th) and superior and inferior endplates thicknesses (EP.Th.S and EP.Th.I) were measured using microcomputed tomography for 27 cadaveric L1 vertebrae. Volumetric cancellous, shell and integral bone mineral densities (vBMD, shBMD and iBMD) as well as vertebral volume (V), height and width were measured using high resolution CT. Areal whole vertebral body and regional BMDs were measured using dual energy x-ray absorptiometry (DXA) in coronal and lateral views. Specimens were then uniaxially compressed to 15% of their height to obtain vertebral stiffness (K) and strength (Fmax) as well as displacement (D), force (F) and energy (W) properties at characteristic points of the load-displacement curve including yield (y), fracture (f), compaction (c), final displacement (t) and residual after unload (r). Correlation and principal component analyses suggested displacements to failure (Df), collapse (Dc) and recovery (Dr) contain information distinct from strength and stiffness. Bone size (V) was present, independently, in multiple regression models of K, Fy, Wy, Fmax, Df, Wt, Wfc and Dr (p < 0.05 to p < 0.0001), areal BMD in models of Dy, Wy, Fmax, Wf, Fc, Wt, Wyf and Wct (p < 0.04 to p < 0.0001), Sh.Th in models of Df, Fc and εr (p < 0.02 to p < 0.002), EP.Th.S in models of Fc and Wct (p < 0.004 to p < 0.0006), EP.Th.I in the model of Wct (p < 0.02), FD in models of Fy, Dy and Fmax (p < 0.03 to p < 0.004), Tb.Sp in models of K and Dy (p < 0.002 to p < 0.0004), Conn.Dn in the model of Df (p < 0.0009), and SMI in the model of Wt (p < 0.02). R2adj varied from 0.12 (Dr) to 0.80 (Wt) for the multiple regression models for all significant variables. In conclusion, there is distinct information in forces and displacements associated with characteristic events occurring during uniaxial compression and recovery, specifically in displacements associated with compaction and recovery. Though there are common factors such as bone mass for some, distinct cancellous and cortical features likely contribute to these events in L1. The descriptive data reported here are expected to provide reference values for comparative and model building efforts, and the relationships found are expected to provide insight into mechanical functions of an L1 vertebra.

Measuring the thickness of vertebral endplate and shell using digital tomosynthesis.

The vertebral endplate and cortical shell play an important structural role and contribute to the overall strength of the vertebral body, are at highest risk of initial failure, and are involved in degenerative disease of the spine. The ability to accurately measure the thickness of these structures is therefore important, even if difficult due to relatively low resolution clinical imaging. We posit that digital tomosynthesis (DTS) may be a suitable imaging modality for measurement of endplate and cortical shell thickness owing to the ability to reconstruct multiplanar images with good spatial resolution at low radiation dose. In this study, for 25 cadaveric L1 vertebrae, average and standard deviation of endplate and cortical shell thickness were measured using images from DTS and microcomputed tomography (µCT). For endplate thickness measurements, significant correlations between DTS and µCT were found for all variables when comparing thicknesses measured in both the overall endplate volume (R2 = 0.25-0.54) and when measurements were limited to a central range of coronal or sagittal slices (R2 = 0.24-0.62). When compared to reference values from the overall shell volume, DTS thickness measurements were generally nonsignificant. However, when measurement of cortical shell thickness was limited to a range of central slices, DTS outcomes were significantly correlated with reference values for both sagittal and coronal central regions (R2 = 0.21-0.49). DTS may therefore offer a means for measurement of endplate thickness and, within a limited sagittal or coronal measurement volume, for measurement of cortical shell thickness.

Ingreso de nitrógeno y fósforo al lago Atitlán (Guatemala) vía deposición atmosférica / Input of Nitrogen and Phosphorus to Lake Atitlán (Guatemala) via atmospheric deposition

La deposición de nutrientes por vía atmosférica tiene graves impactos sobre la ecología de bosques y cuerpos de agua templados. Sin embargo, su importancia en cuerpos de agua neotropicales casi no ha sido estudiada. En este artículo se cuantifica la contribución de nitrógeno inorgánico disuelto (NID, [NO3--N + NH4+-N]) y fósforo inorgánico soluble (FIS, [PO4-3-P]) depositados en bulto sobre superficies húmedas por vía atmosférica hacia el lago Atitlán (Guatemala). Las cargas estimadas de NID y FIS consecuencia de la deposición atmosférica directa (depositada sobre la superficie del lago) fueron de 151.2 ton/año y 5.6 ton/año, respectivamente. Con estos resulta-dos, se estima que el aporte de FIS por deposición atmosférica al lago Atitlán es comparable al de sus principales ríos tributarios, y de casi el doble para el ingreso de NID. Las estimaciones para el lago Atitlán son mayores que lo reportado para otros lagos. Nuestro estudio proporciona información básica para entender la eutrofización del lago Atitlán, enfatizado en la importancia de la deposición atmosférica como contribuyente al deterioro de este cuerpo de agua. Además, demuestra la necesidad de extender este tipo de estudio a otras cuencas neotropicales y la importancia de minimizar este impacto.

Atmospheric nutrient deposition has serious impacts on the ecology of forests and temperate water bodies nevertheless its importance in Neotropical water bodies has hardly been studied. Here we quantify the contribution of bulk atmospheric deposition on wet surfaces of dissolved inorganic nitrogen (DIN,[NO3--N + NH4+-N])and soluble inorganic phosphorus (SIP, [PO4-3-P])into Lake Atitlán (Guatemala). The estimated NID and SIP loads from this direct deposition on the lake surface were respectively, 151.2 tons/year and 5.6 tons/year. With these results, we estimated that the SIP input from atmospheric deposition to Lake Atitlán is comparable to that from the lake's main tributary rivers, whereas for DIN entry this is almost twice as much. Estimates for Lake Atitlán are higher than those reported for many lakes. Our study provides basic information towards understanding the eutrophication of Lake Atitlán, emphasizes the importance of atmospheric deposition in this process and the need for additional studies to document the process in neotropical watersheds.

Onchocerca lupi causing ocular disease in two cats.

Although canine ocular onchocerciasis has been well described as an emerging pathogen of dogs in Europe and North America over the past 20 years, there are no previous reports of feline ocular onchocerciasis. This report details the clinical, histopathologic, and molecular diagnosis of two domestic short hair cats residing in the United States infected with Onchocerca lupi causing episcleritis and orbital cellulitis. The results of this report suggest that O. lupi is a newly recognized disease of domestic cats.