Inferior vena cava collapsibility index as a predictor of fluid responsiveness in sepsis-related acute circulatory failure

Background Assessing fluid responsiveness is the key to successful resuscitation of critically-ill sepsis patients. The use of IVC variation is favored among the dynamic methods of fluid responsiveness assessment in the ICU because it is non-invasive and inexpensive; moreover, it does not demand a high level of training. The aim of this study is to determine the value of the IVC respiratory variability for predicting fluid responsiveness in spontaneously breathing sepsis patients with acute circulatory failure. Results In this prospective observational study, fifty-eight spontaneously breathing sepsis patients admitted in the ICU were enrolled after the approval of the departmental Research Ethical Committee, and the informed written consent had been taken from the patients. Ultrasonographic and echocardiographic parameters were measured “IVC parameters and stroke volume (SV)” with calculation of the inferior vena cava collapsibility index (IVCCI) and cardiac output. These values were obtained before (baseline) and after volume expansion with a fluid bolus. The study showed that twenty-nine patients (50%) were considered to be responders, with an increase in CO by 10% or more after fluid challenge. There was a significant difference between responders and non-responders in baseline IVCCI (p value < 0.001). There were no significant differences between responders and non-responders in terms of demographic and baseline clinical characteristics. Also, there was statistically significantly larger maximum (IVC max) and minimum (IVC min) inferior vena cava diameters before volume expansion in non-responders than in responders with p value 0.037 and 0.001 respectively. The suggested cut off value regarding baseline IVCCI to predict response to fluid infusion is 0.32 with a high chance of response above this figure (a sensitivity of 72.41% and a specificity of 82.76%). Conclusions Inferior vena cava collapsibility index assessment can be a sensitive and a good predictor of fluid responsiveness, being based on a safe and a non-invasive technique compared to other methods such as central venous pressure (CVP) measurement and pulmonary artery catheter insertion.

Left ventricular longitudinal strain variations assessed by speckle-tracking echocardiography after a passive leg raising maneuver in patients with acute circulatory failure to predict fluid responsiveness: A prospective, observational study

Background An association was reported between the left ventricular longitudinal strain (LV-LS) and preload. LV-LS reflects the left cardiac function curve as it is the ratio of shortening over diastolic dimension. The aim of this study was to determine the sensitivity and specificity of LV-LS variations after a passive leg raising (PLR) maneuver to predict fluid responsiveness in intensive care unit (ICU) patients with acute circulatory failure (ACF). Methods Patients with ACF were prospectively included. Preload-dependency was defined as a velocity time integral (VTI) variation greater than 10% between baseline (T0) and PLR (T1), distinguishing the preload-dependent (PLD+) group and the preload-independent (PLD-) group. A 7-cycles, 4-chamber echocardiography loop was registered at T0 and T1, and strain analysis was performed off-line by a blind clinician. A general linear model for repeated measures was used to compare the LV-LS variation (T0 to T1) between the two groups. Results From June 2018 to August 2019, 60 patients (PLD+ = 33, PLD- = 27) were consecutively enrolled. The VTI variations after PLR were +21% (±8) in the PLD+ group and -1% (±7) in the PLD- group (p<0.01). Mean baseline LV-LS was -11.3% (±4.2) in the PLD+ group and -13.0% (±4.2) in the PLD- group (p = 0.12). LV-LS increased in the whole population after PLR +16.0% (±4.0) (p = 0.04). The LV-LS variations after PLR were +19.0% (±31) (p = 0.05) in the PLD+ group and +11.0% (±38) (p = 0.25) in the PLD- group, with no significant difference between the two groups (p = 0.08). The area under the curve for the LV-LS variations between T0 and T1 was 0.63 [0.48–0.77]. Conclusion Our study confirms that LV-LS is load-dependent; however, the variations in LV-LS after PLR is not a discriminating criterion to predict fluid responsiveness of ICU patients with ACF in this cohort.

Comparison of mean systemic pressure in patients with acute circulatory failure receiving passive leg raising vs. pneumatic leg compression

Background: Driving pressure of venous return (VR) is determined by a pressure gradient between mean systemic pressure (Pms) and central venous pressure (CVP). While passive leg raising (PLR) and pneumatic leg compression PC (PC) can increase VR, no study has explored the effects of these two procedures on Pms and VR-related hemodynamic variables. Methods: Forty patients with acute circulatory failure were enrolled in this analysis. All patients obtained both PLR and PC, and were measured for Pms, CVP, mean arterial pressure (MAP), cardiac output (CO), VR resistance (RVR), and systemic vascular resistance (SVR) at baseline and immediately after procedures. To minimize carry over effect, the patients were divided in 2 groups based on procedure sequence which were 1) patients receiving PLR first then PC (PLR-first), and 2) patients receiving PC first then PLR (PC-first). Both groups waited for a washout period before performing the 2 second procedure. Primary outcome was difference in Pms between PLR and PC procedures. Secondary outcome were differences in CVP, MAP, CO, RVR, and SVR between PLR and PC procedures. Results: No difference was found in baseline characteristics and no carry over effect was observed between the 2 groups of patients. Compared with baseline, both PLR and PC significantly increased Pms, CVP, MAP, and CO. PLR increased Pms (9.0±2.3 vs 4.8±1.7 mmHg, p<0.001), CVP (4.5±1.2 vs. 1.6±0.7 mmHg, p<0.001), MAP (22.5±5.6 vs. 14.4±5.0 mmHg, p<0.001), and CO (1.5±0.5 vs. 0.5±0.2 L/min, p<0.001) more than PC. However, PC, also significantly increased RVR (16 ± 27.2 dyn.s/cm5, p=0.001) and SVR (78.4 ± 7.2 dyn.s/cm5, p<0.001) but no difference in PLR group. Conclusion: Among patients with acute circulatory failure, PLR increased Pms, CVP, MAP, and CO more than PC.

Comparison of mean systemic pressure in patients with acute circulatory failure receiving passive leg raising vs. pneumatic leg compression

Background: Driving pressure of venous return (VR) is determined by a pressure gradient between mean systemic pressure (Pms) and central venous pressure (CVP). While passive leg raising (PLR) and pneumatic leg compression PC (PC) can increase VR, no study has explored the effects of these two procedures on Pms and VR-related hemodynamic variables. Methods: Forty patients with acute circulatory failure were enrolled in this analysis. All patients obtained both PLR and PC, and were measured for Pms, CVP, mean arterial pressure (MAP), cardiac output (CO), VR resistance (RVR), and systemic vascular resistance (SVR) at baseline and immediately after procedures. To minimize carry over effect, the patients were divided in 2 groups based on procedure sequence which were 1) patients receiving PLR first then PC (PLR-first), and 2) patients receiving PC first then PLR (PC-first). Both groups waited for a washout period before performing the 2 second procedure. Primary outcome was difference in Pms between PLR and PC procedures. Secondary outcome were differences in CVP, MAP, CO, RVR, and SVR between PLR and PC procedures. Results: No difference was found in baseline characteristics and no carry over effect was observed between the 2 groups of patients. Compared with baseline, both PLR and PC significantly increased Pms, CVP, MAP, and CO. PLR increased Pms (9.0±2.3 vs 4.8±1.7 mmHg, p<0.001), CVP (4.5±1.2 vs. 1.6±0.7 mmHg, p<0.001), MAP (22.5±5.6 vs. 14.4±5.0 mmHg, p<0.001), and CO (1.5±0.5 vs. 0.5±0.2 L/min, p<0.001) more than PC. However, PC, also significantly increased RVR (16 ± 27.2 dyn.s/cm5, p=0.001) and SVR (78.4 ± 7.2 dyn.s/cm5, p<0.001) but no difference in PLR group. Conclusion: Among patients with acute circulatory failure, PLR increased Pms, CVP, MAP, and CO more than PC.

Comparison of Mean Systemic Pressure in Patients with Acute Circulatory Failure Receiving Passive Leg Raising vs. Pneumatic Leg Compression.

Background: Driving pressure of venous return (VR) is determined by mean systemic pressure (Pms) and central venous pressure (CVP). While passive leg raising (PLR) and pneumatic leg compression PC (PC) can increase VR, there is no study explore the effects of these two procedures on Pms and VR-related hemodynamic variables.Methods: Forty patients with acute circulatory failure were included in this analysis. All patients were performed both PLR and PC, and were measured for Pms, CVP, mean arterial pressure (MAP), cardiac output (CO), VR resistance (RVR), and systemic vascular resistance (SVR) at baseline and immediately after procedures. To minimized carry-on effect, the patients were divided into 2 groups based on procedure sequence which were 1) the patients who received PLR first then PC (PLR-first), and 2) the patients who received PC first then PLR (PC-first). Both groups were waited for washing period before performed 2nd procedure. Primary outcome was difference in Pms between PLR and PC procedure. Secondary outcome were differences in CVP, MAP, CO, RVR, and SVR between PLR and PC procedure.Results: There was no difference in baseline characteristics and no carry-on effect between 2 groups of patients. Compared to baseline, both PLR and PC significantly increased Pms, CVP, MAP, and CO. Compared to PC, PLR more increased Pms (9.0±2.3 vs 4.8±1.7 mmHg, p<0.001), CVP (4.5±1.2 vs. 1.6±0.7 mmHg, p<0.001), MAP (22.5±5.6 vs. 14.4±5.0 mmHg, p<0.001), and CO (1.5±0.5 vs. 0.5±0.2 L/min, p<0.001). PC, but not PLR also significantly increased RVR (16 ± 27.2 dyn.s/cm5, p=0.001) and SVR (78.4 ± 7.2 dyn.s/cm5, p<0.001) .Conclusion: In patients with acute circulatory failure, PLR more increased Pms, CVP, MAP, and CO than PC.