Can vena cava ultrasound-guided volume repletion prevent general induced hypotension in elderly patients? A mini-fluid challenge

Background Hypotension is often occurring after induction of general anesthesia (IGA) and can cause organ hypoperfusion and ischemia which associated with adverse outcomes in patients having both cardiac and non-cardiac surgery. Elderly patients are particularly more vulnerable and at increased risk to the depressant effect of anesthetic drugs. So, recognition and prevention of such event are of clinical importance. This study recruited patients aged above 60 years, with ASA physical status classification I-II-III who were scheduled for surgery under general anesthesia with the aim to assess the effectiveness of preoperative IVC ultrasonography in predicting hypotension which develops following IGA and its association with the volume status in elderly patients receiving general anesthesia, through measurements of the maximum inferior vena cava diameter (dIVCmax), minimum inferior vena cava diameter (dIVCmin), inferior vena cava collapsibility index (IVC-CI), and basal and post-induction mean arterial pressure (MAP). Results Thirty-nine (44.3%) of the 88 patients developed hypotension after IGA, and it was significantly more in patients who did not receive preoperative fluid (p = 0.045). The cut-off for dIVCmax was found as 16.250 mm with the ROC analysis. Specificity and sensitivity for the cut-off value of 16.250 mm were calculated as 61.2% and 76.9%, respectively. The cut-off for IVC-CI was found as 33.600% with the ROC analysis. Specificity and sensitivity for the cut-off value of 33.600% were calculated as 68.7% and 87.2%, respectively. Conclusions IVC ultrasonography may be helpful in the prediction of preoperative hypovolemia in elderly patients in the form of high IVC-CI and low dIVCmax. The incidence of hypotension was lower in patients who received fluid infusion before IGA.

Preanesthetic Ultrasonography Assessment of Inferior Vena Cava Diameter in the Supine Position, Left Lateral Tilt Position, and with the Left Uterine Displacement Maneuver in Full-Term Pregnant Women: A Randomized Cross-Over Design Study

BackgroundWe used preanesthetic ultrasonography evaluation to study the effectiveness of left lateral tilt position (LLT) and the left uterine displacement maneuver (LUD) on increasing inferior vena cava diameter (IVCD) in healthy full-term pregnant women, using a randomized, single blinded, cross-over design study.MethodsTwenty-two parturients scheduled for elective cesarean section under spinal anesthesia were recruited. All patients were sequentially placed in the supine position (SPN), LLT and with LUD before induction of spinal anesthesia. Indices of IVCD, measured by subxiphoid ultrasonography, including maximum IVCD (IVCDmax), minimum IVCD (IVCDmin) and collapsibility index (CI), and hemodynamic parameters, such as heart rate and blood pressure, were recorded in each of the postures. Mean or median values of all measurements were compared among the postures.ResultsThe mean values of IVCDmax observed with both LLT and LUD were significantly larger than those in the SPN, respectively (SPN vs. LLT: P <0.05, SPN vs. LUD: P <0.01), although there were no significant differences between IVCDmax with LLT and LUD. There were no significant differences in IVCDmin, CI and hemodynamic parameters between any of the postures. IVCDmax was highest with LUD in 11 patients (55%), in the LLT position in seven patients (35%) and in the SPN in two patients (10%).ConclusionsLLT and LUD might be equally effective in enlarging the narrowed IVCD as compared to SPN. However, both LLT and LUD might not necessarily be appropriate treatment to relieve IVC compression in some cases.Trial registrationThis study was registered in the “UMIN Clinical Trials Registry” (ID no.: 000024344, date. 10th October 2016).

Does respiratory variation in inferior vena cava diameter predict fluid responsiveness in adult patients? A systematic review and meta-analysis of diagnostic accuracy studies

Objectives: To systematically review the diagnostic utility of the respiratory variation of the inferior vena cava diameter measured using ultrasonography for predicting fluid responsiveness in adult patients and compare the three commonly used equations, inferior vena cava distensibility, inferior vena cava collapsibility and inferior vena cava variability. Methods: We searched PubMed, Scopus, Web of Science and Cochrane library, and included studies investigating the diagnostic accuracy of the respiratory variation of the inferior vena cava measured using ultrasonography compared to a reference standard for measuring cardiac output after a fluid challenge for fluid responsiveness, and stratified participants as fluid responsive or not. We included studies conducted in the emergency department or intensive care unit. We excluded studies on paediatric, prehospital, cancer, pregnant, dialysis patients or healthy volunteers. Results: We retrieved 270 records and excluded 171 because of irrelevance, patient population or publication type. We screened the abstracts of 99 studies and then the full texts of 42 studies. Overall, 21 studies with 1321 patients were included, of whom 689 (52%) were fluid responsive. The mean threshold value for positive inferior vena cava distensibility, inferior vena cava collapsibility and inferior vena cava variability was 17%, 35% and 12%, respectively. The heterogeneity between studies was high. Bivariate diagnostic random-effects meta-analysis was used to calculate the summary receiver operating characteristics curves. The overall accuracy, sensitivity and specificity of respiratory variation of the inferior vena cava diameter were 0.85, 0.72 and 0.81, respectively. The accuracy of inferior vena cava distensibility and inferior vena cava collapsibility was similar. The diagnostic utility of respiratory variation of the inferior vena cava diameter was lower but not statistically significant in mechanically ventilated patients compared with spontaneous breathing for predicting fluid responsiveness. Conclusion: The respiratory variation of the inferior vena cava diameter has moderate diagnostic utility for predicting fluid responsiveness independent of the equation used.

New approaches to sonomorphometry of the inferior vena cava in children

Objective: to develop a criterion for normality/abnormality of the inferior vena cava diameter in children that is convenient to use in wide clinical practice.Material. In order to achieve the above objective, we performed measurements of the antero-posterior cross-section of the inferior vena cava in children (n = 100) in different age periods.Results. We have determined a criterion allowing of assessing the normality/abnormality of the inferior vena cava diameter in different age periods with sufficiently high accuracy.Conclusion. The work has concluded on the potential of the use of the coefficient reflecting the ratio of height and diameter (range — 0.04–0.1) as a reliable reference point for the assessment of the normality / abnormality of the inferior vena cava diameter in different age periods.