Fluid Responsiveness In Patients Research Articles

Use of stepwise lung recruitment maneuver to predict fluid responsiveness under lung protective ventilation in the operating room

Recent research has revealed that hemodynamic changes caused by lung recruitment maneuvers (LRM) with continuous positive airway pressure can be used to identify fluid responders. We investigated the usefulness of stepwise LRM with increasing positive end-expiratory pressure and constant driving pressure for predicting fluid responsiveness in patients under lung protective ventilation (LPV). Forty-one patients under LPV were enrolled when PPV values were in a priori considered gray zone (4% to 17%). The FloTrac-Vigileo device measured stroke volume variation (SVV) and stroke volume (SV), while the patient monitor measured pulse pressure variation (PPV) before and at the end of stepwise LRM and before and 5 min after fluid challenge (6 ml/kg). Fluid responsiveness was defined as a ≥ 15% increase in the SV or SV index. Seventeen were fluid responders. The areas under the curve for the augmented values of PPV and SVV, as well as the decrease in SV by stepwise LRM to identify fluid responders, were 0.76 (95% confidence interval, 0.61–0.88), 0.78 (0.62–0.89), and 0.69 (0.53–0.82), respectively. The optimal cut-offs for the augmented values of PPV and SVV were > 18% and > 13%, respectively. Stepwise LRM -generated augmented PPV and SVV predicted fluid responsiveness under LPV.

Value of carotid corrected flow time or changes value of FTc could be more useful in predicting fluid responsiveness in patients undergoing robot-assisted gynecologic surgery: a prospective observational study.

The aim of this study was to evaluate the ability of point-of-care Doppler ultrasound measurements of carotid corrected flow time and its changes induced by volume expansion to predict fluid responsiveness in patients undergoing robot-assisted gynecological surgery. In this prospective study, carotid corrected flow time was measured using Doppler images of the common carotid artery before and after volume expansion. The stroke volume index at each time point was recorded using noninvasive cardiac output monitoring with MostCare. Of the 52 patients enrolled, 26 responded. The areas under the receiver operating characteristic curves of the carotid corrected flow time and changes in carotid corrected flow time induced by volume expansion were 0.82 and 0.67, respectively. Their optimal cut-off values were 357 and 19.5 ms, respectively. Carotid corrected flow time was superior to changes in carotid corrected flow time induced by volume expansion for predicting fluid responsiveness in this population.

Feasibility of Fluid Responsiveness Assessment in Patients at Risk for Increased Intracranial Pressure.

Background: Effective fluid management is important for patients at risk of increased intracranial pressure (ICP). Maintaining constant cerebral perfusion represents a challenge, as both hypovolemia and fluid overload can severely impact patient outcomes. Fluid responsiveness tests, commonly used in critical care settings, are often deemed potentially hazardous for these patients due to the risk of disrupting cerebral perfusion. Methods: This single-center, prospective, clinical observational study enrolled 40 patients at risk for increased ICP, including those with acute brain injury. Informed consent was obtained from each participant or their legal guardians before inclusion. The study focused on the dynamics of ICP and cerebral perfusion pressure (CPP) changes during the Passive Leg Raise Test (PLRT) and the End-Expiratory Occlusion Test (EEOT). Results: The results demonstrated that PLRT and EEOT caused minor and transient increases in ICP, while consistently maintaining stable CPP. EEOT induced significantly lower ICP elevations, making it particularly suitable for use in high-risk situations. Conclusions: PLRT and EEOT can be considered feasible and safe for assessing fluid responsiveness in patients at risk for increased ICP. Notably, EEOT stands out as a preferred method for high-risk patients, offering a dependable strategy for fluid management without compromising cerebral hemodynamics.

CAROTID ARTERY ULTRASOUND FOR ASSESSING FLUID RESPONSIVENESS IN PATIENTS UNDERGOING MECHANICAL VENTILATION WITH LOW TIDAL VOLUME AND PRESERVED SPONTANEOUS BREATHING.

Objective : This study aimed to investigate whether changes in carotid artery corrected flow time (ΔFTc bolus ) and carotid artery peak flow velocity respiratory variation (Δ V peak bolus ) induced by the fluid challenge could reliably predict fluid responsiveness in mechanically ventilated patients with a tidal volume < 8 mL/kg Predicted Body Weight while preserving spontaneous breathing. Methods : Carotid artery corrected flow time, Δ V peak, and hemodynamic data were measured before and after administration of 250 mL crystalloids. Fluid responsiveness was defined as a 10% or more increase in stroke volume index as assessed by noninvasive cardiac output monitoring after the fluid challenge. Results : A total of 43 patients with acute circulatory failure were enrolled in this study. Forty-three patients underwent a total of 60 fluid challenges. The ΔFTc bolus and Δ V peak bolus showed a significant difference between the fluid responsiveness positive group (n = 35) and the fluid responsiveness negative group (n = 25). Spearman correlation test showed that ΔFTc bolus and Δ V peak bolus with the relative increase in stroke volume index after fluid expansion ( r = 0.5296, P < 0.0001; r = 0.3175, P = 0.0135). Multiple logistic regression analysis demonstrated that ΔFTc bolus and Δ V peak bolus were significantly correlated with fluid responsiveness in patients with acute circulatory failure. The areas under the receiver operating characteristic curves of ΔFTc bolus and Δ V peak bolus for predicting fluid responsiveness were 0.935 and 0.750, respectively. The optimal cutoff values of ΔFTc bolus and Δ V peak bolus were 0.725 (sensitivity = 97.1%, specificity = 84%) and 4.21% (sensitivity = 65.7%, specificity = 80%), respectively. Conclusion : In mechanically ventilated patients with a tidal volume < 8 mL/kg while preserving spontaneous breathing, ΔFTc bolus and Δ V peak bolus could predict fluid responsiveness. The predictive performance of ΔFTc bolus was superior to Δ V peak bolus .

Respiratory variation in the internal jugular vein does not predict fluid responsiveness in the prone position during adolescent idiopathic scoliosis surgery: a prospective cohort study

BackgroundRespiratory variation in the internal jugular vein (IJVV) has not shown promising results in predicting volume responsiveness in ventilated patients with low tidal volume (Vt) in prone position. We aimed to determine whether the baseline respiratory variation in the IJVV value measured by ultrasound might predict fluid responsiveness in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with low Vt.MethodsAccording to the fluid responsiveness results, the included patients were divided into two groups: those who responded to volume expansion, denoted the responder group, and those who did not respond, denoted the non-responder group. The primary outcome was determination of the value of baseline IJVV in predicting fluid responsiveness (≥15% increases in stroke volume index (SVI) after 7 ml·kg-1 colloid administration) in patients with AIS undergoing PSF during low Vt ventilation. Secondary outcomes were estimation of the diagnostic performance of pulse pressure variation (PPV), stroke volume variation (SVV), and the combination of IJVV and PPV in predicting fluid responsiveness in this surgical setting. The ability of each parameter to predict fluid responsiveness was assessed using a receiver operating characteristic curve.ResultsFifty-six patients were included, 36 (64.29%) of whom were deemed fluid responsive. No significant difference in baseline IJVV was found between responders and non-responders (25.89% vs. 23.66%, p = 0.73), and no correlation was detected between baseline IJVV and the increase in SVI after volume expansion (r = 0.14, p = 0.40). A baseline IJVV greater than 32.00%, SVV greater than 14.30%, PPV greater than 11.00%, and a combination of IJVV and PPV greater than 64.00% had utility in identifying fluid responsiveness, with a sensitivity of 33.33%, 77.78%, 55.56%, and 55.56%, respectively, and a specificity of 80.00%, 50.00%, 65.00%, and 65.00%, respectively. The area under the receiver operating characteristic curve for the baseline values of IJVV, SVV, PPV, and the combination of IJVV and PPV was 0.52 (95% CI, 0.38–0.65, p=0.83), 0.54 (95% CI, 0.40–0.67, p=0.67), 0.58 (95% CI, 0.45–0.71, p=0.31), and 0.57 (95% CI, 0.43–0.71, p=0.37), respectively.ConclusionsUltrasonic-derived IJVV lacked accuracy in predicting fluid responsiveness in patients with AIS undergoing PSF during low Vt ventilation. In addition, the baseline values of PPV, SVV, and the combination of IJVV and PPV did not predict fluid responsiveness in this surgical setting.Trail registrationThis trial was registered at www.chictr.org (ChiCTR2200064947) on 24/10/2022. All data were collected through chart review.

Association of infraclavicular axillary vein diameter and collapsibility index with general anesthesia-induced hypotension in elderly patients undergoing gastrointestinal surgery: an observational study

BackgroundThe collapse index of inferior Vena Cava (IVC) and its diameter are important predictive tools for fluid responsiveness in patients, especially critically ones. The collapsibility of infraclavicular axillary vein (AXV) can be used as an alternative to the collapsibility of IVC (IVC-CI) to assess the patient’s blood volume.MethodsA total of 188 elderly patients aged between 65 and 85 years were recruited for gastrointestinal surgery under general anesthesia. Ultrasound measurements AXV and IVC were performed before induction of general anesthesia. Patients were grouped in accordance to the hypotension after induction. ROC curves were used to analyze the predictive value of ultrasound measurements of AXV and IVC for hypotension after induction of anesthesia. Pearson linear correlation was used to assess the correlation of ultrasound measurements and decrease in mean arterial blood pressure (MAP).ResultsThe maximum diameter of AXV(dAXVmax) and the maximum diameter of IVC (dIVCmax) were not related to the percentage decrease in MAP; the collapsibility of AXV (AXV-CI) and IVC-CI were positively correlated with MAP changes (correlation coefficients:0.475, 0.577, respectively, p < 0.001). The areas under the curve (AUC) was 0.824 (0.759–0.889) for AXV-CI, and 0.874 (0.820–0.928) for IVC-CI. The optimal threshold for AXV-CI was 31.25% (sensitivity 71.7%, specificity 90.1%), while for IVC-CI was 36.60% (sensitivity 85.9%, specificity 79.0%). Hypotension and down-regulation of MAP during induction can be accurately predicted by AXV-Cl after correction for confounding variables.ConclusionInfraclavicular axillary vein diameter has no significant correlation with postanesthesia hypotension, whereas AXV-CI may predict postanesthesia hypotension during gastrointestinal surgery of the elderly.Trial registrationThis study was registered in the Clinical Trial Registry of China on 05/06/2022 (ChiCTR2200060596).

Supine transfer test-induced changes in cardiac index predict fluid responsiveness in patients without intra-abdominal hypertension

BackgroundThe reversible maneuver that mimics the fluid challenge is a widely used test for evaluating volume responsiveness. However, passive leg raising (PLR) does have certain limitations. The aim of the study is to determine whether the supine transfer test could predict fluid responsiveness in adult patients with acute circulatory failure who do not have intra-abdominal hypertension, by measuring changes in cardiac index (CI).MethodsSingle-center, prospective clinical study in a 25-bed surgery intensive care unit at the Fudan University Shanghai Cancer Center. Thirty-four patients who presented with acute circulatory failure and were scheduled for fluid therapy. Every patient underwent supine transfer test and fluid challenge with 500 mL saline for 15–30 min. There were four sequential steps in the protocol: (1) baseline-1: a semi-recumbent position with the head of the bed raised to 45°; (2) supine transfer test: patients were transferred from the 45° semi-recumbent position to the strict supine position; (3) baseline-2: return to baseline-1 position; and (4) fluid challenge: administration of 500 mL saline for 15–30 min. Hemodynamic parameters were recorded at each step with arterial pulse contour analysis (ProAQT/Pulsioflex). A fluid responder was defined as an increase in CI ≥ 15% after fluid challenge. The receiver operating characteristic curve and gray zone were defined for CI.ResultsSeventeen patients were fluid challenge. The r value of the linear correlations was 0.73 between the supine transfer test- and fluid challenge-induced relative CI changes. The relative changes in CI induced by supine transfer in predicting fluid responsiveness had an area under the receiver operating characteristic curve of 0.88 (95% confidence interval 0.72–0.97) and predicted a fluid responder with 76.5% (95% confidence interval 50.1–93.2) sensitivity and 88.2% (95% confidence interval 63.6–98.5) specificity, at a best threshold of 5.5%. Nineteen (55%) patients were in the gray zone (CI ranging from -3 and 8 L/min/m2).ConclusionThe supine transfer test can potentially assist in detecting fluid responsiveness in patients with acute circulatory failure without intra-abdominal hypertension. Nevertheless, the small threshold and the 55% gray zone were noteworthy limitation.Trial registrationPredicting fluid responsiveness with supine transition test (ChiCTR2200058264). Registered 2022–04-04 and last refreshed on 2023–03-26, https://www.chictr.org.cn/showproj.html?proj=166175.

Comparison of the carotid corrected flow time and tidal volume challenge for assessing fluid responsiveness in robot-assisted laparoscopic surgery.

We aimed to compare the ability of carotid corrected flow time assessed by ultrasound and the changes in dynamic preload indices induced by tidal volume challenge predicting fluid responsiveness in patients undergoing robot-assisted laparoscopic gynecological surgery in the modified head-down lithotomy position. This prospective single-center study included patients undergoing robot-assisted laparoscopic surgery in the modified head-down lithotomy position. Carotid Doppler parameters and hemodynamic data, including corrected flow time, pulse pressure variation, stroke volume variation, and stroke volume index at a tidal volume of 6mL/kg predicted body weight and after increasing the tidal volume to 8mL/kg predicted body weight (tidal volume challenge), respectively, were measured. Fluid responsiveness was defined as a stroke volume index ≥ 10% increase after volume expansion. Among the 52 patients included, 26 were classified as fluid responders and 26 as non-responders based on the stroke volume index. The area under the receiver operating characteristic curve measured to predict the fluid responsiveness to corrected flow time and changes in pulse pressure variation (ΔPPV6-8) after tidal volume challenge were 0.82 [95% confidence interval (CI) 0.71-0.94; P < 0.0001] and 0.85 (95% CI 0.74-0.96; P < 0.0001), respectively. The value for pulse pressure variation at a tidal volume of 8mL/kg was0.79 (95% CI 0.67-0.91; P = 0.0003). The optimal cut-off values for corrected flow time and ΔPPV6-8 were 357ms and > 1%, respectively. Both the corrected flow time and Changes in pulse pressure variation after tidal volume challenge reliably predicted fluid responsiveness in patients undergoing robot-assisted laparoscopic gynecological surgery in the modified head-down lithotomy position. And pulse pressure variation at a tidal volume of 8mL/kg maybe also a useful predictor.Trial registration: Chinese Clinical Trial Register (CHiCTR2200060573, Principal investigator: Hongliang Liu, Date of registration: 05/06/2022).

THE ACCURACY OF INFERIOR VENA CAVA DISTENSIBILITY THROUGH THE TRANSHEPATIC APPROACH TO PREDICT FLUID RESPONSIVENESS IN PATIENTS WITH SEPTIC SHOCK AFTER EMERGENCY LAPAROTOMY.

Background: We aimed to evaluate the ability of inferior vena cava (IVC) distensibility using the transhepatic approach to predict fluid responsiveness in mechanically ventilated patients with septic shock after emergency laparotomy. Methods: This prospective observational study included mechanically ventilated paralyzed adult who had septic shock after emergency laparotomy. The IVC dimensions were measured through the transhepatic and subxiphoid approaches. The fluid responsiveness was confirmed with >15% increase in cardiac output after 500 mL of fluid bolus. The outcomes were the ability of transhepatic (primary outcome) and subxiphoid approach to predict fluid responders using the area under the receiver operating characteristics curve analysis. The gray zone for the two approaches was calculated. Results: Data from 51 patients were analyzed, and the number of fluid responders was 30 of 52 (58%). The transhepatic approach was feasible in all patients, whereas the subxiphoid approach was only feasible in 42 patients. The area under the receiver operating characteristics curve (95% confidence interval) for the transhepatic IVC distensibility was 0.88 (0.76-0.95), and it was comparable with that of the subxiphoid approach (0.81 [0.66-0.92], P = 0.417). The gray zone for the transhepatic IVC distensibility was 17% to 35% including 24 of 51 patients (47%), whereas the gray zone for the subxiphoid IVC distensibility was 13% to 34% including 18 of 42 patients (43%). Conclusion: In conclusion, the transhepatic approach for evaluation of IVC distensibility showed good accuracy in predicting fluid responsiveness in patients with septic shock after emergency laparotomy. The transhepatic approach showed the same accuracy as the subxiphoid approach with the advantage of being feasible in larger number of patients.

Tidal volume challenge-induced hemodynamic changes can predict fluid responsiveness during one-lung ventilation: an observational study.

To evaluate the ability of tidal volume challenge (VTC)-induced hemodynamic changes to predict fluid responsiveness in patients during one-lung ventilation (OLV). 80 patients scheduled for elective thoracoscopic surgery with OLV were enrolled. The inclusion criteria were: age ≥ 18 years, American Society of Anesthesiologists physical status I-III, normal right ventricular function, normal left ventricular systolic function (ejection fraction ≥55%), and normal or slightly impaired diastolic function. The study protocol was implemented 15 min after starting OLV. Simultaneous recordings were performed for hemodynamic variables of diameter of left ventricular outflow tract, velocity time integral (VTI) of aortic valve, and stroke volume (SV), and ΔSV-VTC, ΔVTI-VTC, and ΔMAP-VTC were calculated at four time points: with VT 5 mL/kg (T1); after VT increased from 5 mL/kg to 8 mL/kg and maintained at this level for 2 min (T2); after VT was adjusted back to 5 mL/kg for 2 min (T3); and after volume expansion (250 mL of 0.9% saline infused over 10-15 min) (T4). Patients were considered as responders to fluid administration if SV increased by ≥10%. Receiver operating characteristic (ROC) curves for percent decrease in SV, VTI, and MAP by VTC were generated to evaluate their ability to discriminate fluid responders from nonresponders. Of the 58 patients analyzed, there were 32 responders (55%) and 26 nonresponders (45%). The basic characteristics were comparable between the two groups (p > 0.05). The area under the curve (AUC) for ΔSV-VTC, ΔVTI-VTC, and ΔMAP-VTC to discriminate responders from nonresponders were 0.81 (95% CI: 0.68-0.90), 0.79 (95% CI: 0.66-0.89), and 0.56 (95% CI: 0.42-0.69). The best threshold for ΔSV-VTC was -16.1% (sensitivity, 78.1%; specificity, 84.6%); the best threshold for ΔVTI-VTC was -14.5% (sensitivity, 78.1%; specificity, 80.8%). Tidal volume challenge-induced relative change of stroke volume and velocity time integral can predict fluid responsiveness in patients during one-lung ventilation.Clinical Trial Registration: Chinese Clinical Trial Registry, No: chictr210051310.

Usefulness of the velocity–time integral of the left ventricular outflow tract variability index to predict fluid responsiveness in patients undergoing cardiac surgery

BackgroundHaemodynamic monitoring of patients after cardiac surgery using echocardiographic evaluation of fluid responsiveness is both challenging and increasingly popular. We evaluated fluid responsiveness in the first hours after surgery by determining the variability of the velocity–time integral of the left ventricular outflow tract (VTI-LVOT).MethodsWe conducted a cross-sectional study of 50 consecutive adult patients who underwent cardiac surgery and in whom it was possible to obtain VTI-LVOT measurements. We then determined the variability and correlations with our pulse pressure variation (PPV) measurements to predict fluid responsiveness.ResultsA strong positive correlation was seen between the VTI-LVOT variability index absolute values and PPV for predicting fluid responsiveness in the first hours after cardiac surgery. We also found that the VTI-LVOT variability index has high specificity and a high positive likelihood ratio compared with the gold standard using a cut-off point of ≥ 12%.ConclusionsThe VTI-LVOT variability index is a valuable tool for determining fluid responsiveness during the first 6 postoperative hours in patients undergoing cardiac surgery.

RESPIRATORY VARIABILITY OF VALVULAR PEAK SYSTOLIC VELOCITY AS A NEW INDICATOR OF FLUID RESPONSIVENESS IN PATIENTS WITH SEPTIC SHOCK.

Objective: The aim of this study was to evaluate the reliability and feasibility of pulse Doppler measurements of peak velocity respiratory variability of mitral and tricuspid valve rings during systole as new dynamic indicators of fluid responsiveness in patients with septic shock. Methods: Transthoracic echocardiography (TTE) was performed to measure the respiratory variability of aortic velocity-time integral (∆VTI), respiratory variability of tricuspid annulus systolic peak velocity (∆RVS), respiratory variability of mitral annulus systolic peak velocity (∆LVS), and other related indicators. Fluid responsiveness was defined as a 10% increase in cardiac output after fluid expansion, assessed by TTE. Results: A total of 33 patients with septic shock were enrolled in this study. First, there was no significant difference in the population characteristics between the fluid responsiveness positive group (n = 17) and the fluid responsiveness negative group (n = 16) ( P > 0.05). Second, Pearson correlation test showed that ∆RVS, ∆LVS, and TAPSE with the relative increase in cardiac output after fluid expansion ( R = 0.55, P = 0.001; R = 0.40, P = 0.02; R = 0.36, P = 0.041). Third, multiple logistic regression analysis demonstrated that ∆RVS, ∆LVS, and TAPSE were significantly correlated with fluid responsiveness in patients with septic shock. Fourth, receiver operating characteristic (ROC) curve analysis revealed that ∆VTI, ∆LVS, ∆RVS, and TAPSE had good predictive ability for fluid responsiveness in patients with septic shock. The area under the curve (AUC) of ∆VTI, ∆LVS, ∆RVS, and TAPSE for predicting fluid responsiveness was 0.952, 0.802, 0.822, and 0.713, respectively. The sensitivity (Se) values were 1.00, 0.73, 0.81, and 0.83, whereas the specificity (Sp) values were 0.84, 0.91, 0.76, and 0.67, respectively. The optimal thresholds were 0.128, 0.129, 0.130, and 13.9 mm, respectively. Conclusion: Tissue Doppler ultrasound evaluation of respiratory variability of mitral and tricuspid annular peak systolic velocity could be a feasible and reliable method for the simple assessment of fluid responsiveness in patients with septic shock.

Stroke Volume Variation is a Good Predictor of Fluid Responsiveness in Cardiac Surgery Patients with Implanted Intra-aortic Balloon Pump

There is a vast body of evidence in favour of individualising fluid therapy using dynamic hemodynamic indices like stroke volume variation (SVV). Patients with implanted intra-aortic balloon pump (IABP) are excluded from this approach because of pulse contour artifacts caused by the pump. The aim of this work is to test whether SVV can be used for fluid responsiveness prediction in these patients. Patients after cardiac surgery with implanted IABP were included in this study. SVV was measured after placing the IABP on standby mode for one minute. Cardiac output (CO) measurement was obtained via Swan-Ganz catheter before and after a 6 ml/kg fluid challenge. Fluid responsiveness was defined as increase of CO by at least 10%. SVV above 8.5% showed a good correlation with fluid responsiveness. Sensitivity was 95 (95% CI 85 to 100) and specificity 82 (95% CI 72 to 92). SVV had an area under the ROC curve 0.91 (95% CI 0.81 to 1.0) SVV is a good predictor of fluid responsiveness in patients with IABP. SVV should not be excluded as a fluid therapy guide for these patients. Placing the pump on standby for one minute allows obtaining an accurate measurement of this important variable.

Can carotid artery Doppler variations induced by the end-expiratory occlusion maneuver predict fluid responsiveness in septic shock patients?

BackgroundAn increase in cardiac index (CI) during an end-expiratory occlusion test (EEOt) predicts fluid responsiveness in ventilated patients. However, if CI monitoring is unavailable or the echocardiographic window is difficult, using the carotid Doppler (CD) could be a feasible alternative to track CI changes. This study investigates whether changes in CD peak velocity (CDPV) and corrected flow time (cFT) during an EEOt were correlated with CI changes and if CDPV and cFT changes predicted fluid responsiveness in patients with septic shock.MethodsProspective, single-center study in adults with hemodynamic instability. The CDPV and cFT on carotid artery Doppler and hemodynamic variables from the pulse contour analysis EV1000™ were recorded at baseline, during a 20-s EEOt, and after fluid challenge (500 mL). We defined responders as those who increased CI ≥ 15% after a fluid challenge.ResultsWe performed 44 measurements in 18 mechanically ventilated patients with septic shock and without arrhythmias. The fluid responsiveness rate was 43.2%. The changes in CDPV were significantly correlated with changes in CI during EEOt (r = 0.51 [0.26–0.71]). A significant, albeit lower correlation, was found for cFT (r = 0.35 [0.1–0.58]). An increase in CI ≥ 5.35% during EEOt predicted fluid responsiveness with 78.9% sensitivity and 91.7% specificity, with an area under the ROC curve (AUROC) of 0.85. An increase in CDPV ≥ 10.5% during an EEOt predicted fluid responsiveness with 96.2% specificity and 53.0% sensitivity with an AUROC of 0.74. Sixty-one percent of CDPV measurements (from − 13.5 to 9.5 cm/s) fell within the gray zone. The cFT changes during EEOt did not accurately predict fluid responsiveness.ConclusionsIn septic shock patients without arrhythmias, an increase in CDPV greater than 10.5% during a 20-s EEOt predicted fluid responsiveness with > 95% specificity. Carotid Doppler combined with EEOt may help optimize preload when invasive hemodynamic monitoring is unavailable. However, the 61% gray zone is a major limitation (retrospectively registered on Clinicaltrials.gov NCT04470856 on July 14, 2020).

Accuracy of stroke volume variation and pulse pressure variation in predicting fluid responsiveness undergoing one-lung ventilation during thoracic surgery: a systematic review and meta-analysis.

Stroke volume variation (SVV) and pulse pressure variation (PPV) are based on the interaction between the heart and lungs during mechanical ventilation. However, debate continues as to whether SVV and PPV can accurately predict fluid responsiveness during the one-lung ventilation (OLV). We therefore undertook a systematic review and meta-analysis of clinical trials that investigated the diagnostic value of SVV and PPV in predicting fluid responsiveness undergoing OLV during thoracic surgery. The MEDLINE, EMBASE, WANFANG, and CENTRAL databases were systematically searched for studies on the use of SVV and/or PPV in patients undergoing OLV from 2010 to 2021. Heterogeneity was assessed using I2 statistics. The funnel diagram analysis was used to test publication bias. A fixed-effects model was used to calculate the pooled values of sensitivity, specificity, the diagnostic odds ratio (DOR), and the relevant 95% confidence intervals (95% CIs). The summary receiver operating characteristic (SROC) curves were estimated, and the areas under the SROC curve were calculated. In total nine studies, comprising 452 patients were ultimately included in this meta-analysis, including 217 (48%) responders and 235 (52%) nonresponders. After combining the correlation coefficients, a slight heterogeneity was found between SVV and PPV in these selected studies (I2 SVV =19.7%, I2 PPV =15.3%), and the funnel diagram also showed that the P values of SVV and PPV were 0.33 and 0.26. After the pooled analysis, the respective sensitivity of SVV and PPV in predicting fluid responsiveness was 0.66 and 0.61, the specificity was 0.62 and 0.53, the positive likelihood ratios were 1.7 and 1.3, the negative likelihood ratios were 0.55 and 0.74, and the DORs were 3 and 2. The areas under the SROC curve of SVV and PPV were 0.68 and 0.60, respectively, according to STATA SE16 software, and the combined areas under the receiver operating characteristic (ROC) curve of SVV and PPV were 0.681 and 0.604, respectively, according to MedCalc19.0.4 software. Current evidence suggests that SVV and PPV are not suitable for guiding intraoperative fluid therapy due to their poor ability to predict fluid responsiveness in patients undergoing OLV, and we need a better indicator instead.

Haemodynamic monitoring and management in patients having noncardiac surgery

BACKGROUND Haemodynamic monitoring and management is a mainstay of peri-operative anaesthetic care. OBJECTIVE To determine how anaesthesiologists measure and manage blood pressure and cardiac output, and how they guide fluid administration and assess fluid responsiveness in patients having noncardiac surgery. DESIGN Web-based survey. SETTING Survey among members of the European Society of Anaesthesiology and Intensive Care (ESAIC) in October and November 2021. PARTICIPANTS ESAIC members responding to the survey. MAIN OUTCOME MEASURES Respondents’ answers to 30 questions on haemodynamic monitoring and management, and fluid therapy. RESULTS A total of 615 fully completed surveys were analysed. Arterial catheters are usually not placed before induction of general anaesthesia (378/615; 61%) even when invasive blood pressure monitoring is planned. Mean arterial pressure (532/615; 87%) with lower intervention thresholds of 65 mmHg (183/531; 34%) or 20% below pre-operative baseline (166/531; 31%) is primarily used to guide blood pressure management. Cardiac output is most frequently measured using pulse wave analysis (548/597; 92%). However, only one-third of respondents (almost) always use cardiac output to guide haemodynamic management in high-risk patients (225/582; 39%). Dynamic cardiac preload variables are more frequently used to guide haemodynamic management than cardiac output [pulse pressure variation (almost) always: 318/589; 54%]. Standardised treatment protocols are rarely used for haemodynamic management (139/614; 23%). For fluid therapy, crystalloids are primarily used as maintenance fluids, to treat hypovolaemia, and for fluid challenges. The use of 0.9% saline and hydroxyethyl starch has declined over the last decade. The preferred methods to assess fluid responsiveness are dynamic preload variables and fluid challenges, most commonly with 250 ml of fluid (319/613; 52%). CONCLUSION This survey provides important information how anaesthesiologists currently measure and manage blood pressure and cardiac output, and how they guide fluid administration in patients having noncardiac surgery.

Carotid artery corrected flow time and respiratory variation of blood flow peak velocity for prediction of hypotension after induction of general anesthesia in adult patients undergoing emergency laparotomy for peritonitis: A prospective, observational study.

Doppler waveform analysis of carotid artery has been found to predict fluid responsiveness in patients undergoing elective surgeries. We evaluated the role of carotid artery corrected flow time (FTc) and respiratory variation of blood flow peak velocity (ðVpeak) in predicting post induction hypotension in patients undergoing emergency laparotomy for peritonitis. Adult patients (n = 60) with perforation peritonitis undergoing emergency laparotomy under general anesthesia (GA) were recruited in this prospective, observational study. Carotid ultrasonography was performed pre-induction, to determine FTc and ðVpeak. Post-induction hemodynamic parameters were recorded for 5 minutes. Spearman's rank correlation coefficient was used to determine the relationship between hypotension and carotid artery measurements. Post-induction hypotension occurred in 48.3% of patients. The carotid artery FTc was significantly lower (P = 0.008) in patients who developed post-induction hypotension, but ðVpeak was statistically similar (P = 0.62) in both groups. Spearman's rank correlation coefficient revealed a statistically significant correlation between FTc and systolic blood pressure (SBP) change at one-minute post induction (r2 = -0.29, P = 0.03); however statistical significance were not achieved at 2 minutes and 3 minutes (P = 0.05 at both time points). Carotid artery FTc had an area under the receiver operating characteristic (AUROC) curve (95% CI) of 0.70 (0.57-0.84) to predict post-induction hypotension and best cutoff value of 344.8 ms with a sensitivity and specificity of 61% and 79%, respectively. Carotid artery ðVpeak had an AUROC curve (95% CI) of 0.54 (0.39-0.69) to predict post-induction hypotension and best cutoff value of 7.9% with a sensitivity and specificity of 62% and 55%, respectively. Carotid artery FTc and ðVpeak are not reasonable predictors of hypotension in patients undergoing emergency laparotomy for perforation peritonitis.

End-expiratory Occlusion Test and Mini-fluid Challenge Test for Predicting Fluid Responsiveness in Acute Circulatory Failure.

Predicting which patients with acute circulatory failure will respond to the fluid by an increase in cardiac output is a daily challenge. End-expiratory occlusion test (EEOT) and mini-fluid challenge (MFC) can be used for assessing fluid responsiveness in patients with spontaneous breathing activity, cardiac arrhythmias, low-tidal volume and/or low lung compliance. The objective of the study is to evaluate the value of EEOT and MFC-induced rise in left ventricular outflow tract (LVOT) velocity time integral (VTI) in predicting fluid responsiveness in acute circulatory failure in comparison to the passive leg-raising (PLR) test. Hundred critically ill ventilated and sedated patients with acute circulatory failure were studied. LVOT VTI was measured by transthoracic echocardiography before and after EEOT (interrupting the ventilator at end-expiration over 15 s), and before and after MFC (100 ml of Ringer lactate was infused over 1 min). The variation of LVOT VTI after EEOT and the MFC was calculated from the baseline. Sensitivity, specificity, and area under the receiver-operating characteristic (AUROC) curve of LVOT VTI after EEOT and MFC to predict fluid responsiveness were determined. After PLR, stroke volume (SV) increased by ≥12% in 49 patients, who were defined as responders and 34 patients in whom the increase in SV <12% were defined as nonresponders. A cutoff of 9.1% Change in VTI after MFC (ΔVTIMFC) predicted fluid responsiveness with an AUROC of 0.96 (P < 0.001) with sensitivity and specificity of 91.5% and 88.9%, respectively. Change in VTI after EEOT (ΔVTIEEOT) >4.3% predicted fluid responsiveness with sensitivity and specificity 89.4% and 88.9%, respectively, with an AUROC of 0.97 (P < 0.001), but in 17 patients, EEOT was not possible because triggering of the ventilator by the patient's inspiratory effort. In conclusion, in mechanically ventilated patients with acute circulatory failure Δ VTIMFC and Δ VTI EEOT accurately predicts fluid responsiveness.

Dynamic Indices for the Prediction of Fluid Responsiveness in Laparoscopic Urologic Surgery under General Anaesthesia: An Interventional Study

Objective: This study aims to evaluate the ability of stroke volume variation (SVV), pulse pressure variation (PPV), and change in PVV and SVV after tidal volume challenge testing (ΔPPV and ΔSVV) aiming to predict fluid responsiveness in patients undergoing laparoscopic urologic surgery. Material and Methods: A prospective interventional study was performed with 23 patients undergoing urologic surgery while they were placed in Trendelenburg positions. A Vigileo/FloTrac system was used for the analysis. Hemodynamic data such as: arterial pressure (MAP), heart rate (HR), peak airway pressure (PIP), stroke volume (SV), cardiac output (CO), SVV, and PPV were recorded at the tidal volume settings of 8 mL/kg and 12 mL/kg before, and after a fluid challenge (FC). Fluid responsiveness was defined as an increase in SV(ΔSV) ≥15.0%. Results: After tidal volume challenge tests, there were significant increases in PIP in both groups. PPV increased only in the responders, as opposed to SVV, which increased significantly only in non-responders after tidal volume challenge test. After fluid challenge, PVV and SVV decreased gradually and significantly in both groups. The area under the ROC curves of patients undergoing laparoscopic urologic surgery was 0.872 (95% CI: 0.57-0.96) for ΔPPV, this change was the highest compared to other parameters. The threshold of the ΔPPV of patients undergoing laparoscopic urologic surgery was 4% with a sensitivity at 0.75 and specificity at 0.93. Conclusion: Change in PPV after the tidal volume challenge test from 8 mL/kg to 12 mL/kg can be used as an effective indicator to monitor fluid responsiveness in regards to patients undergoing urologic surgery.

Stroke Volume and Arterial Pressure Fluid Responsiveness in Patients With Elevated Stroke Volume Variation Undergoing Major Vascular Surgery: A Prospective Intervention Study

The identification of potential hemodynamic indicators to increase the predictive power of stroke-volume variation (SVV) for mean arterial pressure (MAP) and stroke volume (SV) fluid responsiveness. A prospective intervention study. At a single-center university hospital. Nineteen patients during major vascular surgery with 125 fluid interventions. When SVV ≥13% occurred for >30 seconds, 250 mL of Ringer's lactate were given within 2 minutes. Hemodynamic variables, such as pulse-pressure variation (PPV) and dynamic arterial elastance (Edyn), were measured by pulse power-wave analysis. The outcomes were MAP and SV responsiveness, defined as an increase of at least 10% of MAP and SV within 5 minutes of the fluid intervention. Of the fluid interventions, 48% were MAP-responsive, and 66% were SV-responsive. The addition of PPV and Edyn cut-off values to the SVV cut-off decreased sensitivity from 1-to-0.66 to-0.82, and concomitantly increased specificity from 0-to- 0.65-to-0.93 for the prediction of MAP and SV responsiveness in the authors' study setting. The areas under the receiver operating characteristic curves of PPV and Edyn for the prediction of MAP responsiveness were 0.79 and 0.75, respectively. The areas under the receiver operating characteristic curves for PPV and Edyn to predict SV responsiveness were 0.85 and 0.77, respectively. The PPV and Edyn showed good accuracy for the prediction of MAP and SV responsiveness in patients with elevated SVV during vascular surgery. Either PPV or Edyn may be used in conjunction with SVV to better predict MAP and SV fluid responsiveness in patients undergoing vascular surgery.