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101.
The pressure in the proximal axillary vein (AVP) was compared with central venous pressure (CVP) in eight patients during and after elective abdominal surgery. Both pressures were recorded from soft, elastic, polyurethane catheters inserted in the basilic or cephalic veins ("half-way" catheters), punctured at the fossa cubiti (AVP), and via the right jugular vein (CVP). The AVP and CVP were recorded simultaneously using hydrostatic, conventional disposable venous pressure measurement sets. The measurements were performed during intermittent positive pressure ventilation with positive end-expiratory pressure from 0 to 7.5 cmH2O (0-0.74 kPa), as well as during spontaneous breathing. During both controlled and spontaneous respiration, small mean differences (0.2-1.0 cmH2O) (0.02-0.1 kPa), and a highly significant (P less than 0.001) positive correlation between CVP- and AVP-values were found. An increase of 1 cmH2O (0.10 kPa) in the CVP was associated with an increment of practically identical order (0.99-1.04 cmH2O) (0.10-0.11 kPa) in the AVP. The results suggest that monitoring of the AVP by a basilic "half-way" catheter produces diagnostic information similar to that from the measurement of the CVP from subclavian, external or internal jugular, as well as "long-way" brachial catheter, with no risk of the major mechanical complications which accompany the use of the latter catheters.  相似文献   
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Impaired nutrition status is recognized as a risk factor for worse clinical outcomes in patients with chronic obstructive pulmonary disease (COPD). The aims of this study were to investigate how undernutrition is diagnosed, its prevalence, and whether there is an association between this condition and clinical outcomes in patients with COPD. The search for this systematic review of observational studies (PROSPERO: CRD42020191888) was performed in the PubMed, Embase, and Scopus databases, with no date or language restrictions. The studies had to report data on the diagnosis of undernutrition and its association with mortality, exacerbation, length of hospital stay, or quality of life in adult patients with COPD. A meta-analysis with a random-effects model was performed to combine data. Forty-nine studies were included (20 of them classified as having a low risk of bias), and the most common diagnostic method of undernutrition was body mass index (BMI) (n = 36). The pooled prevalence of undernutrition was equal to 20% (95% CI, 0.15–0.25; I² = 100%), and it was associated with mortality (risk ratio = 1.97; 95% CI, 1.55–2.50; I² = 98%), exacerbation (risk ratio = 1.73; 95% CI, 1.03–2.91; I² = 96%), and poorer quality of life (mean difference = 8.25; 95% CI, 5.40–11.10; I² = 79%). For all outcomes, the certainty of evidence was very low. In conclusion, undernutrition is prevalent and is associated with poorer outcomes in patients with COPD. However, undernutrition is mainly diagnosed by BMI, which underreports its prevalence, and the certainty of the evidence is very low.  相似文献   
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