Needle biopsy-derived myofascial tissue samples are sufficient for quantification of myofibroblast density.

Quantification of myofibroblasts is a promising method for assessing tissue properties in the field of fascia research. This is commonly performed by immunohistochemistry for α-smooth muscle actin. However, usually larger tissue samples sizes are required for quantification. The aim of this investigation was to explore whether a microscopic quantification of myofibroblasts can be conducted with fascial tissue samples derived via percutaneous needle biopsy. Fascial tissues were derived via percutaneous needle biopsy from the fascia lata of 11 persons (aged 19-40 years). Following immunohistochemistry, selected fields for photomicroscopic analysis were chosen by a Monte Carlo method based randomization procedure. On these fields, a digital quantification for the relative density of α-smooth muscle actin was attempted. The newly developed quantification method could successfully be applied in all tissue samples. The median α-smooth muscle actin density in the selected tissue samples ranged between 0% and 1.7% (median 0%, IQR 0%-0.001%). The applied protocol proved to be workable for the purpose of an estimation of the α-smooth muscle actin density in fascial tissue samples derived via percutaneous needle biopsy. Since this type of biopsy is less invasive than the commonly performed open muscle biopsy, this offers a new and useful perspective for future histological investigations of fascial tissue properties in living patients. Clin. Anat. 31:368-372, 2018. © 2018 Wiley Periodicals, Inc.

Systematic review including re-analyses of 1148 individual data sets of central venous pressure as a predictor of fluid responsiveness.

PURPOSE: Central venous pressure (CVP) has been shown to have poor predictive value for fluid responsiveness in critically ill patients. We aimed to re-evaluate this in a larger sample subgrouped by baseline CVP values. METHODS: In April 2015, we systematically searched and included all clinical studies evaluating the value of CVP in predicting fluid responsiveness. We contacted investigators for patient data sets. We subgrouped data as lower (<8 mmHg), intermediate (8-12 mmHg) and higher (>12 mmHg) baseline CVP. RESULTS: We included 51 studies; in the majority, mean/median CVP values were in the intermediate range (8-12 mmHg) in both fluid responders and non-responders. In an analysis of patient data sets (n = 1148) from 22 studies, the area under the receiver operating curve was above 0.50 in the <8 mmHg CVP group [0.57 (95% CI 0.52-0.62)] in contrast to the 8-12 mmHg and >12 mmHg CVP groups in which the lower 95% CI crossed 0.50. We identified some positive and negative predictive value for fluid responsiveness for specific low and high values of CVP, respectively, but none of the predictive values were above 66% for any CVPs from 0 to 20 mmHg. There were less data on higher CVPs, in particular >15 mmHg, making the estimates on predictive values less precise for higher CVP. CONCLUSIONS: Most studies evaluating fluid responsiveness reported mean/median CVP values in the intermediate range of 8-12 mmHg both in responders and non-responders. In a re-analysis of 1148 patient data sets, specific lower and higher CVP values had some positive and negative predictive value for fluid responsiveness, respectively, but predictive values were low for all specific CVP values assessed.

Predicting fluid responsiveness with transthoracic echocardiography is not yet evidence based.

An essential part of intensive care is to accurately identify fluid responders among patients with circulatory failure. Over the past few years, new techniques have been assessed for rapid and non-invasive prediction of fluid responsiveness. As transthoracic echocardiography (TTE) is becoming an integrated tool in the intensive care unit, this systematic review examined studies evaluating the predictive value of TTE for fluid responsiveness. In October 2012, we searched Pubmed, EMBASE and Web of Science for studies evaluating the predictive value of TTE-derived variables for fluid responsiveness defined as change in thermodilution cardiac output or stroke volume after a fluid challenge or a passive leg raising test. The use of thermodilution was used as inclusion criterion because it is the only method validated to show the change in cardiac output or stroke volume, which defines fluid responsiveness. Of the 4294 evaluated citations, only one study fully met our inclusion criteria. In this study, the predictive value of variations in inferior vena cava diameter (> 16%) for fluid responsiveness was moderate with sensitivity of 71% [95% confidence interval (CI) 44-90], specificity of 100% (95% CI 73-100) and an area under the receiver operating curve of 0.90 (95% CI 0.73-0.98). Only one study of TTE-based methods fulfilled the criteria for valid assessment of fluid responsiveness. Before recommending the use of TTE in predicting fluid responsiveness, proper evaluation including thermodilution technique as the gold standard is needed.