ObjectiveTo investigate the diagnostic value of simultaneous culture of central venous catheter (CVC) blood and peripheral blood for catheter-related bloodstream infections (CRBSI). MethodsNon-septic patients who were treated with CVC for 1 to 7 days were enrolled from February 2011 to February 2015 in the First Hospital of Wuhan City. Blood were collected from both peripheral vein and CVC for bacterial culture once a day. The CVCs were removed from patients who got CRBSI from the first to sixth day and who did not by the end of the seventh day for semi-quantitative catheter culture, quantitative catheter culture, CVC culture and catheter exit-site pus culture. The diagnosis of CRBSI were based on 4 methods as follows:A, both peripheral and CVC blood were positive and the time of CVC blood positive were 2 hours earlier than peripheral blood; B, the colonies of semi-quantitative catheter cultures were ≥15 CFU and the microorganisms in both CVC and peripheral blood were the same; C, the colonies ratio of CVC and peripheral blood cultures were ≥5:1; D, the microorganisms in both the peripheral blood and catheter exit-site pus were the same. The diagnostic value of the four methods was compared. ResultsA total of 1 086 patients were finally included. From 1 to 7 days, 64 patients were peripheral blood positive, 79 were CVC blood positive. The patients diagnosed as CRBSI using A, B, C, and D methods were 58, 55, 51, and 36, respectively. Sixty patients were diagnosed as CRBSI based on the clinical and laboratory methods. For the number of patients diagnosed with CRBSI, there was no significant difference between A and B (P>0.05), as well as A and C (P>0.05), however, significant difference was found between A and D (P<0.05). In the diagnostic value of CRBSI, A is similar to B (sensitivity:93.33% vs. 91.67%, specificity:99.81% vs. 100%, Youden index:0.93 vs. 0.92). A, B and C had almost similar specificity (all >99%), however, A had higher sensitivity (93.33% vs. 76.67%, 58.33%) and Youden index (0.93 vs. 0.76, 0.58). ConclusionSimultaneous culture of CVC blood and peripheral blood has a good diagnostic value for CRBSI.
ObjectiveTo investigate the influence of misplaced subclavian vein (SCV) catheter into the ipsilateral internal jugular vein (IJV) on transpulmonary thermodilution (TPTD) measurements and explore the possible mechanisms preliminarily.MethodsIn this prospective study, 408 patients in whom an SCV catheterization was indicated for TPTD monitoring were enrolled. A first set of TPTD measurements was collected at baseline in all patients (group 1, SCV catheters were correctly placed; group 2, SCV catheters were misplaced into the ipsilateral IJV). The parameters included mean transit time (MTt), downslope time (DSt), cardiac index (CI), global end-diastolic volume index (GEDVI) and extra-vascular lung water index (EVLWI). A second set of TPTD measurements was performed only in those with catheter misplacement immediately after the misplaced SCV catheters being corrected (Group 3). The differences in MTt, DSt, GEDVI and EVLWI between group 2 and 3 were recorded as ΔMTt, ΔDSt, ΔGEDVI and ΔEVLWI, respectively.ResultsGEDVI and EVLWI were significantly higher (all P<0.001) in group 2 than those in group 1, while CI was not significantly different (P>0.05) between these two groups. Multivariate logistic regression identified PaO2/FiO2 [adjusted odds ratio (OR) 1.492/10 mm Hg; 95% confidence interval (CI), 1.180 - 1.884; P<0.001], GEDVI (OR=1.307/10 mL/m2, 95% CI 1.131 - 1.511; P<0.001) and EVLWI (OR=3.05; 95%CI 1.593 - 5.840; P<0.001) as the 3 independent factors associated with the misplacement of SCV catheter into the ipsilateral IJV. In group 2, GEDVI [(1041±122)mL/m2 vs. (790±102)mL/m2, P<0.001], EVLWI [(20.3±4.0)mL/kg vs. (10.3±2.3)mL/kg, P<0.001], CI [(3.6±1.2)L·min–1·m–2 vs. (2.9±1.0)L·min–1·m–2, P<0.001], MTt [(38.2±13.3)s vs. (30.8±9.4)s, P<0.001] and DSt [(18.9±7.2)s vs. (13.2±4.9)s, P<0.001)] were significantly higher than those in Group 3. Multiple regression analysis demonstrated that ΔEVLWI (R2=0.86, P<0.001) was negatively correlated with ΔMTt (coefficient±SE, –0.52±0.12; P<0.001) and positively correlated with ΔDSt (coefficient±SE, 1.45±0.17; P<0.001).ConclusionsDuring TPTD measurements, indicator injection through an SCV catheter misplaced into the ipsilateral IJV results in an overestimation of CI, GEDVI and EVLWI. The increase in DSt might be a key factor in explaining the overestimation of EVLWI in patients with misplaced SCV catheters. Given that the accurate measurements of GEDVI and EVLWI are of utmost importance for guiding resuscitation and decision-making regarding fluids administration, immediate repositioning is required if a misplacement is suspected and confirmed by the chest X-ray.
ObjectiveTo evaluate the diagnostic accuracy and efficacy of X-ray for evaluating the tip position of umbilical venous catheterization (UVC). MethodsThe PubMed, Embase, Cochrane Library, CBM, CNKI, VIP and WanFang Data databases were electronically searched to collect diagnostic tests for UVC tip localisation from inception to 1 May 2023. Two reviewers independently screened the literature according to the inclusion and exclusion criteria, extracted the data and assessed the quality of the studies using the QUADAS-2 tool. Then, meta-analysis was performed by using Stata 16.0 software. Results Twelve articles involving 1 055 patients were included. The sensitivity and specificity of Negar Yazdani’s study were both 100%. The results of the meta-analysis (the remaining eleven articles, n=951) indicated a pooled sensitivity of 0.7 (95%CI 0.6 to 0.8), a pooled specificity of 0.8 (95%CI 0.7 to 0.9), a positive likelihood ratio of 4.0 (95%CI 2.0 to 8.1), a negative likelihood ratio of 0.4 (95%CI 0.2 to 0.6) and a diagnostic odds ratio of 11 (95%CI 3 to 36) with an area under the cumulative receiver operating characteristic curve of 0.8 (95%CI 0.8 to 0.9). A subgroup analysis was performed according to the different methods of judging X, the 8th–9th thoracic, the 9th–10th thoracic and combined judgement of the diaphragmatic plane + the vertebral body + the heart shadow. The sensitivities of the 3 groups were 0.8 (95%CI 0.5 to 0.9), 0.5 (95%CI 0.4 to 0.7) and 0.8 (95%CI 0.6 to 0.9); the specificities of the 3 groups were 0.8 (95%CI 0.6 to 0.9), 0.76 (95%CI 0.6 to 0.9) and 0.91 (95%CI 0.79 to 0.96). The areas under the cumulative receiver operating characteristic curve were 0.9 (95%CI 0.8 to 0.9), 0.7 (95%CI 0.6 to 0.7) and 0.92 (95%CI 0.89 to 0.94). ConclusionSome error is present when determining the catheter tip position by X-ray, in which the evaluation of the umbilical vein catheter tip position through a comprehensive evaluation of the diaphragmatic plane, the heart margin and the vertebral body is more powerful than the evaluation of the vertebral body alone.