Effect of subclavian vein diameter combined with perioperative fluid therapy on preventing post-induction hypotension in patients with ASA status I or II.

BACKGROUND: Perioperative hypotension is frequently observed following the initiation of general anesthesia administration, often associated with adverse outcomes. This study assessed the effect of subclavian vein (SCV) diameter combined with perioperative fluid therapy on preventing post-induction hypotension (PIH) in patients with lower ASA status. METHODS: This two-part study included patients aged 18 to 65 years, classified as ASA physical status I or II, and scheduled for elective surgery. The first part (Part I) included 146 adult patients, where maximum SCV diameter (dSCVmax), minimum SCV diameter (dSCVmin), SCV collapsibility index (SCVCI) and SCV variability (SCVvariability) assessed using ultrasound. PIH was determined by reduction in mean arterial pressure (MAP) exceeding 30% from baseline measurement or any instance of MAP < falling below 65 mmHg for ≥ a duration of at least 1 min during the period from induction to 10 min after intubation. Receiver Operating Characteristic (ROC) curve analysis was employed to determine the predictive values of subclavian vein diameter and other relevant parameters. The second part comprised 124 adult patients, where patients with SCV diameter above the optimal cutoff value, as determined in Part I study, received 6 ml/kg of colloid solution within 20 min before induction. The study evaluated the impact of subclavian vein diameter combined with perioperative fluid therapy by comparing the observed incidence of PIH after induction of anesthesia. RESULTS: The areas under the curves (with 95% confidence intervals) for SCVCI and SCVvariability were both 0.819 (0.744-0.893). The optimal cutoff values were determined to be 45.4% and 14.7% (with sensitivity of 76.1% and specificity of 86.7%), respectively. Logistic regression analysis, after adjusting for confounding factors, demonstrated that both SCVCI and SCVvariability were significant predictors of PIH. A threshold of 45.4% for SCVCI was chosen as the grouping criterion. The incidence of PIH in patients receiving fluid therapy was significantly lower in the SCVCI ≥ 45.4% group compared to the SCVCI < 45.4% group. CONCLUSIONS: Both SCVCI and SCVvariability are noninvasive parameters capable of predicting PIH, and their combination with perioperative fluid therapy can reduce the incidence of PIH.

Prevention of hypotension after induction of general anesthesia using point-of-care ultrasound to guide fluid management: a randomized controlled trial.

PURPOSE: Hypotension after induction of general anesthesia (GAIH) is common and is associated with postoperative complications including increased mortality. Collapsibility of the inferior vena cava (IVC) has good performance in predicting GAIH; however, there is limited evidence whether a preoperative fluid bolus in patients with a collapsible IVC can prevent this drop in blood pressure. METHODS: We conducted a single-centre randomized controlled trial with adult patients scheduled to undergo elective noncardiac surgery under general anesthesia (GA). Patients underwent a preoperative point-of-care ultrasound scan (POCUS) to identify those with a collapsible IVC (IVC collapsibility index ≥ 43%). Individuals with a collapsible IVC were randomized to receive a preoperative 500 mL fluid bolus or routine care (control group). Surgical and anesthesia teams were blinded to the results of the scan and group allocation. Hypotension after induction of GA was defined as the use of vasopressors/inotropes or a decrease in mean arterial pressure < 65 mm Hg or > 25% from baseline within 20 min of induction of GA. RESULTS: Forty patients (20 in each group) were included. The rate of hypotension after induction of GA was significantly reduced in those receiving preoperative fluids (9/20, 45% vs 17/20, 85%; relative risk, 0.53; 95% confidence interval, 0.32 to 0.89; P = 0.02). The mean (standard deviation) time to complete POCUS was 4 (2) min, and the duration of fluid bolus administration was 14 (5) min. Neither surgical delays nor adverse events occurred as a result of the study intervention. CONCLUSION: A preoperative fluid bolus in patients with a collapsible IVC reduced the incidence of GAIH without associated adverse effects. STUDY REGISTRATION: ClinicalTrials.gov (NCT05424510); first submitted 15 June 2022.

RéSUMé: OBJECTIF: L'hypotension après induction de l'anesthésie générale (AG) est fréquente et est associée à des complications postopératoires, notamment à une augmentation de la mortalité. La collapsibilité de la veine cave inférieure (VCI) a été utilisée avec succès pour prédire la l'hypotension post-induction de l'AG; cependant, il existe peu de données probantes qu'un bolus liquidien préopératoire chez les patient·es présentant une collapsibilité de la VCI puisse prévenir cette baisse de la tension artérielle. MéTHODE: Nous avons réalisé une étude randomisée contrôlée monocentrique auprès de patient·es adultes devant bénéficier d'une chirurgie non cardiaque non urgente sous anesthésie générale. Les patient·es ont passé une échographie préopératoire ciblée (POCUS) pour identifier les personnes présentant une collapsibilité de la VCI (indice de collapsibilité de la VCI ≥ 43 %). Les personnes présentant une collapsibilité de la VCI ont été randomisées à recevoir un bolus de liquide préopératoire de 500 mL ou des soins de routine (groupe témoin). Les équipes chirurgicales et d'anesthésie ne connaissaient pas les résultats de l'examen ni l'attribution des groupes. L'hypotension après induction de l'AG a été définie comme l'utilisation de vasopresseurs/inotropes ou une diminution de la tension artérielle moyenne < 65 mm Hg ou > 25 % par rapport aux valeurs de base dans les 20 minutes suivant l'induction de l'AG. RéSULTATS: Quarante patient·es (20 dans chaque groupe) ont été inclus·es. Le taux d'hypotension après induction de l'AG était significativement réduit chez les personnes recevant des liquides préopératoires (9/20, 45 % vs 17/20, 85 %; risque relatif, 0,53; intervalle de confiance à 95 %, 0,32 à 0,89; P = 0,02). Le temps moyen (écart type) pour compléter l'échographie ciblée était de 4 (2) min, et la durée de l'administration du bolus liquidien était de 14 (5) min. Ni retards chirurgicaux ni effets indésirables ne sont survenus à la suite de l'intervention à l'étude. CONCLUSION: Un bolus liquidien préopératoire chez les patient·es présentant une collapsibilité de la VCI a réduit l'incidence d'hypotension après l'induction de l'anesthésie générale sans effets indésirables associés. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05424510); première soumission le 15 juin 2022.

Inferior vena cava collapsibility index and stroke volume as predictors of blood transfusion in upper gastrointestinal bleeding in the emergency department.

BACKGROUND AND AIM: This study investigates the effectiveness of bedside ultrasonography in predicting blood transfusion requirements in patients with upper gastrointestinal bleeding (UGIB). It focuses on evaluating the inferior vena cava (IVC) diameter, IVC collapsibility index (CI), and stroke volume (SV) as ultrasonographic measures. METHODS: A hundred adult patients enrolled in this prospective clinical study. The patients were divided into two groups (group 1: only saline administered group, group 2: saline and blood administered group). IVC diameter, IVC CI, and SV were measured at the time of admission and after treatment. RESULTS: At the initial admission, group 1 exhibited an IVC CI of 20.4% and an SV of 65.0 mL, whereas group 2 displayed an IVC CI of 26.6% and an SV of 58.0 mL. Upon analyzing the relationship between the Glasgow-Blatchford score (GBS) and SV, we identified a significant negative correlation (r = -0.7350; P < 0.001). Similarly, a weak negative correlation was observed between the Rockall score (RS) and SV (r = -0.4718; P < 0.001). It is worth noting that patients with UGIB require blood transfusion if their SV falls below 62.5 mL, with an area under the curve (AUC) of 89.1% and a 95% confidence interval (CI) ranging from 82.8% to 95.4%. CONCLUSION: IVC CI and SV can be used as parameters to predict the need for blood transfusion in the ED in patients with UGIB.

The diagnostic accuracy of preoperative perfusion index as a predictor of postspinal anesthesia hypotension in parturients undergoing cesarean delivery: A prospective non-blinded observational study.

Background and Objectives: Spinal anesthesia is the technique of choice for elective cesarean section with a prominent side effect of postspinal anesthesia hypotension (PSH). This needs an early prediction to avoid feto-maternal complication. This study aimed to assess the diagnostic accuracy of perfusion index (PI) and inferior vena cava collapsibility index (IVCCI) in the prediction of PSH. Material and Methods: Thirty parturients of American Society of Anesthesiologists Physical Status (ASA-PS) 1 and two undergoing cesarean delivery participated in the study. IVCCI, PI, baseline systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and heart rate (HR) were noted in the preoperative period. The fall of MBP by 20% from baseline or below 65 mm Hg was considered PSH. After spinal anesthesia, SBP, DBP, MBP, and HR were noted again for diagnosing PSH. Results: It did not show any statistical difference when comparing the PI between the PSH and non-PSH groups in both the PSH definition groups. IVCCI was significantly higher when PSH was considered MBP <65 mm Hg (P = 0.01). However, IVCCI was found to be statistically insignificant if PSH was considered a 20% reduction in baseline MBP. The correlation matrix between IVCCI and PI showed Pearson's r-value of 0.525, indicating a substantial relationship between the two (P = 0.003). Multivariate logistic regression analysis had shown that neither IVCCI nor PI was a good predictor of PSH in parturients for both definition groups for PSH. Conclusion: Although there is a modest correlation between PI and IVCCI, both cannot be used to predict postspinal hypotension in parturients undergoing elective lower-segment cesarean section (LSCS).

Use of inferior vena cava guided fluid therapy in the treatment of septic shock: A randomised controlled trial.

INTRODUCTION: By administering inferior vena cava (IVC) directed fluid, it is possible to avoid the use of additional fluid and fluid overload in patients with septic shock (SS) and sepsis-induced hypoperfusion (SIH). METHODOLOGY: In patients with SIH and SS, we conducted prospective observational research on fluid therapy. A time-motion trace of the IVC diameter was created using M-mode imaging. The ability to predict fluid responsiveness was based on the IVC collapsibility index (cIVC) > 40%. Participants were randomised into 2 groups using a permuted block-of-four randomization list, with the investigators being blinded prior to patient allocation. They were split equally between the usual-care (UC) group, which received sepsis-guided fluid treatment, and the interventional ultrasound-guided fluid therapy (UGFT) group. RESULTS: The average age of the participants was 63.2 years (62.8 years for the UGFT group and 63.7 years for the UC group). Co-morbid health conditions were practically the same in both arms at baseline. Prior to enrolment, both groups received the same quantity of fluid as part of resuscitation (UGFT arm received 2.4 0.6 L, UC group received 2.2 0.7 L). The UGFT group outperformed the UC group with a P value of 0.02 due to a significantly lower positive fluid balance after 72 hours of ICU discharge (-1.37 L), which rendered the UGFT group superior to the UC group. Even after accounting for the fluids consumed before enrolment, there was still a sizable difference in the fluids infused. When the pre-enrolment fluids were counted at 72 hours, UGFT participants still displayed a decreased positive fluid balance. However, there was no discernible difference in the 30-day mortality rate overall (6.3% difference, UGFT: 15.7%, and UC: 22.0%). CONCLUSIONS: In contrast to the UC group, the UGFT arm of our study demonstrated a statistically significant benefit of Point of Care USG (POCUS) guided fluid therapy during resuscitation in sepsis in reducing the positive fluid balance in 72 hours, preventing fluid overload, and reducing the need for dialysis and invasive ventilation. However, there was no statistically significant variation in the 30-day mortality rate.

Correlation of Plethysmograph Variability Index with Inferior Vena Cava Index in Spontaneously Breathing Neonates - A Cross Sectional Study.

Inferior vena cava (IVC) indices are commonly used to assess the need for fluid bolus during shock. It needs expertise and is difficult to do during surgical procedures. Plethysmograph variability index (PVI) is a simpler non-invasive tool used to measure fluid responsiveness in adults. However, the data on PVI in neonates is limited. This cross-sectional observational study was done at a tertiary level NICU to correlate PVI and IVC among spontaneously breathing neonates. The PVI was documented using the Masimo Radical 7 pulse oximeter. The IVC collapsibility index (IVC CI) was determined by bedside ultrasound. The Spearman correlation coefficient was analyzed. The PVI showed strong positive correlation with IVC CI (rho = 0.64, 95% CI: 0.474-0.762) (p <0.001). Thus, PVI can be a useful tool for hemodynamic monitoring of neonates. However, further studies are needed before applying it to clinical use.

Inferior vena cava collapsibility index as a predictor of hypotension after induction of general anesthesia in hypertensive patients.

BACKGROUND: Hypertensive patients are more susceptible to develop hypotension after the induction of general anesthesia (GA), most likely due to hypovolemia. An inferior vena cava collapsibility index (IVCCI) > 40-50% can predict hypotension after the induction of GA in the general population by variable accuracies. The current study aimed to investigate IVCCI% as a predictor of postinduction hypotension in hypertensive patients undergoing noncardiac surgery. METHODS: Ultrasound IVCCI % was assessed for all controlled hypertensive patients immediately before induction of GA. After induction of GA, patients were diagnosed with postinduction hypotension if their systolic arterial pressure (SAP) dropped by ≥ 30% of the baseline value and/or mean arterial pressure (MAP) dropped to < 65 mmHg up to 15 min after intubation. The receiver operating characteristic (ROC) curve of IVCCI% was compared to patients' classification either developing hypotension after induction of GA or not as a gold standard. RESULTS: Of the 153 patients who completed the study, 62 (40.5%) developed hypotension after the induction of GA, and 91 (59.5%) did not. An IVCCI > 39% predicted the occurrence of postinduction hypotension with high accuracy (84%) (AUC 0.908, P < 0.001). The area of uncertainty (by gray zone analysis) of IVCCI lies at values from 39 to 45%. This gray zone included 21 patients (13.7% of all patients). CONCLUSION: An inferior vena cava collapsibility index > 39% before anesthetic induction can be a simple noninvasive reliable predictor of hypotension after the induction of GA for hypertensive patients not treated with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) and undergoing noncardiac surgery. TRIAL REGISTRATION: This clinical trial was approved by the Institutional Review Board (IRB) at Zagazig University (ZUIRB #9424 dated 03/04/2022), and patients' informed consent for participation in the study was obtained during the period from May 2022 to May 2023. All study procedures were carried out in accordance with the ethical standards of the Helsinki Declaration of 2013.

Assessing the Efficacy of Inferior Vena Cava Collapsibility Index for Predicting Hypotension after Central Neuraxial Block: A Systematic Review and Meta-Analysis.

The use of ultrasonography to predict spinal-induced hypotension (SIH) has gained significant attention. This diagnostic meta-analysis aimed to investigate the reliability of the inferior vena cava collapsibility index (IVCCI) in predicting SIH in patients undergoing various surgeries. Databases, including Embase, Cochrane Library, Medline, and Google Scholar, were screened until 28 July 2023, yielding 12 studies with 1076 patients (age range: 25.6-79 years) undergoing cesarean section (CS) (n = 4) or non-CS surgeries (n = 8). Patients with SIH had a significantly higher IVCCI than those without SIH (mean difference: 11.12%, 95% confidence interval (CI): 7.83-14.41). The pooled incidence rate of SIH was 40.5%. IVCCI demonstrated satisfactory overall diagnostic reliability (sensitivity, 77%; specificity, 82%). The pooled area under the curve (AUC) was 0.85, indicating its high capability to differentiate patients at risk of PSH. The Fagan nomogram plot demonstrated a positive likelihood ratio (PLR) of 4 and a negative likelihood ratio (NLR) of 0.28. The results underscore the robustness and discriminative ability of IVCCI as a predictive tool for SIH. Nevertheless, future investigations should focus on assessing its applicability to high-risk patients and exploring the potential enhancement in patient safety through its incorporation into clinical practice.

Efficacy of inferior vena cava collapsibility index and caval aorta index in predicting the incidence of hypotension after spinal anaesthesia- A prospective, blinded, observational study.

Background and Aim: Spinal anaesthesia-induced hypotension (SAIH) is a frequent side effect of spinal anaesthesia. SAIH is usually observed in patients with hypovolemia. Ultrasonography has evolved as a non-invasive tool for volume status assessment. Methods: This prospective, blinded, observational study was conducted on 75 adult patients who required spinal anaesthesia after receiving ethical approval and registering the study. Ultrasonographic evaluation of the aorta and the inferior vena cava (IVC) was done preoperatively, and the IVC collapsibility index (IVCCI) and caval aorta index were calculated. The incidence of SAIH was recorded. The strength of the association between different parameters and SAIH was calculated. To find out the value of the optimal cut-off for the prediction of SAIH, receiver operating characteristic (ROC) analysis for various ultrasound parameters was done. The bidirectional stepwise selection was utilised for multivariate analysis to choose the single best predictor. Results: SAIH was observed in 36 patients. Among demographic parameters, age, female gender, and height showed a medium correlation. Among ultrasonographic measurements, minimum IVC internal diameter (IVCmin) and IVCCI showed a strong association with SAIH. The best parameter regarding area under the ROC curve (AUC) and diagnostic accuracy was IVCCI (0.828 and 85%, respectively). On multivariate analysis, age (95% CI [1.01, 1.12], P = 0.024) and IVCCI (95% CI [1.05, 1.18], P < 0.001) were significant independent predictors. At a cut-off point of ≥43.5%, IVCCI accurately predicted SAIH (sensitivity 81% and specificity 90%). Conclusion: Preoperative ultrasonographic assessment of IVC to evaluate its collapsibility index is a convenient, cost-effective, and reproducible tool for predicting SAIH.

The Role of Ultrasonographic Inferior Vena Cava Measurement in the Volume-Based Classification of Patients With Hyponatremia.

OBJECTIVES: To demonstrate the role of inferior vena cava (IVC) collapsibility in the assessment of volume status in hyponatremic critically ill patients in the emergency department (ED) with bedside IVC imaging and to predict volume status with response to fluid therapy. METHODS: A prospective 110 hypotonic hyponatremic patients aged >18 years with a serum sodium level under 125 mEq/L and at least one symptom of hyponatremia, who presented or referred to the ED was conducted. Demographical, clinical, and laboratory characteristics with bedside measurement of IVC diameter of patients were recorded. Volume status was divided into 3 subgroups: hypovolemic-G1, euvolemic-G2, and hypervolemic-G3. An ED trainee with a certification to perform basic and advanced ultrasonography (USG) training carried out the USG examinations. A diagnostic algorithm approach was made according to the results. RESULTS: Symptom severity was significantly greater in the hypervolemic group than the other groups (P = .009 and P = .034, respectively). Systolic blood pressure (SBP) and mean arterial pressure (MAP) were significantly lower in the hypovolemic group compared with the other groups (P < .001 and P = .003, respectively). There was a significant difference between the ultrasonographically measured IVC min, IVC max, and mean IVC values across the three volume-based groups (P < .001). CONCLUSION: Considering the diversity of physical examination (PE) findings, with the highly heterogenous nature of hyponatremia, a new measurable algorithm can be developed on the basis of contemporary hyponatremic patient management guidelines.

The use of preoperative inferior vena cava ultrasound to predict anaesthesia-induced hypotension: a systematic review.

Preoperative ultrasound assessment of inferior vena cava (IVC) diameter and the collapsi-bility index might identify patients with intravascular volume depletion. The purpose of this review was to gather the existing evidence to find out whether preoperative IVC ultrasound (IVCUS) derived parameters can reliably predict hypotension after spinal or general anaesthesia. PubMed was searched to identify research articles that addressed the role of IVC ultrasound in predicting hypotension after spinal and general anaesthesia in adult patients. We included 4 randomized control trials and 17 observational studies in our final review. Among these, 15 studies involved spinal anaesthesia and 6 studies involved general anaesthesia. Heterogeneity with respect to the patient populations under evaluation, definitions used for hypotension after anaesthesia, IVCUS assessment methods, and cut-off values for IVCUS-derived parameters to predict hypotension precluded pooled meta-analysis. The maximum and minimum reported sensitivity of the IVC collapsibility index (IVCCI) for predicting post-spinal hypotension was 84.6% and 58.8% respectively, while the maximum and minimum specificities were 93.1% and 23.5% respectively. For the prediction of hypotension after general anaesthesia induction, the reported ranges of sensitivity and specificity of IVCCI were 86.67% to 45.5% and 94.29% to 77.27%, respectively. Current literature on the predictive role of IVCUS for hypotension after anaesthesia is heterogeneous both in methodology and in results. Standardization of the definition of hypotension under anaesthesia, method of IVCUS assessment, and the cut-offs for IVC diameter and the collapsibility index for prediction of hypotension after anaesthesia are necessary for drawing clinically relevant conclusions.

Role of Internal Jugular Vein Collapsibility Index in Predicting Post-spinal Hypotension in Pregnant Women Undergoing Cesarean Section: A Prospective Observational Study.

Introduction Post-spinal hypotension (PSH) frequently occurs in women undergoing cesarean section. In recent studies, Ultrasound-guided measurements of the internal jugular vein (IJV) have been reported to predict fluid responsiveness. We planned to evaluate the correlation between the internal jugular vein collapsibility index (IJVCI) and PSH in cesarean section patients. Methods Ninety-one parturients who underwent elective lower segment cesarean section with a singleton pregnancy were recruited. Preoperatively, patients were placed in a supine position with a 15-degree left lateral tilt. Maximum (at the end of expiration) and minimum (at the end of inspiration) IJV diameters (mm) and IJVCI were assessed using M-mode imaging during spontaneous and deep breathing. Spinal anaesthesia was performed at the L3-4 or L4-5 level. Systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, respiratory rate, and SpO2 were recorded from baseline till the delivery of the baby. Results Among 91 patients, 40 (45.5%) patients had at least one episode of hypotension. Demographic variables and baseline vitals were comparable between the hypotensive and normotensive groups (p>0.05). In spontaneous and deep breathing, IJV diameter at the end-expiration (IJVdmax), end-inspiration (IJVdmin), and IJVCI amongst both hypotensive and non-hypotensive pregnant women were statistically similar. Receiver Operating Characteristic (ROC) curve analysis showed that during spontaneous breathing, using a cut-off point of 29.5%, IJVCI had a sensitivity and specificity of 70% and 23%, respectively, for predicting PSH; whereas during deep breathing, IJVCI had a sensitivity and specificity of 77% and 27%, respectively, for predicting the same using a cut-off value of 37.5%. Conclusion We conclude that internal jugular vein parameters such as maximum diameter, minimum diameter, and IJVCI during spontaneous and deep breathing cannot be used as reliable predictors of post-spinal hypotension in pregnant patients undergoing elective cesarean section.

Inferior Vena Cava Ultrasonography for Volume Status Evaluation: An Intriguing Promise Never Fulfilled.

The correct determination of volume status is a fundamental component of clinical evaluation as both hypovolaemia (with hypoperfusion) and hypervolaemia (with fluid overload) increase morbidity and mortality in critically ill patients. As inferior vena cava (IVC) accounts for two-thirds of systemic venous return, it has been proposed as a marker of volaemic status by indirect assessment of central venous pressure or fluid responsiveness. Although ultrasonographic evaluation of IVC is relatively easy to perform, correct interpretation of the results may not be that simple and multiple pitfalls hamper its wider application in the clinical setting. In the present review, the basic elements of the pathophysiology of IVC behaviour, potential applications and limitations of its evaluation are discussed.

Role of Inferior Vena Cava Collapsibility Index in the Prediction of Hypotension Associated With Central Neuraxial Block: A Prospective Observational Study.

BACKGROUND: There are only a few studies on perioperative use of inferior vena cava collapsibility index (IVCCI) to predict hypotension after anesthesia. The study aimed to evaluate IVCCI as predictor of hypotension in patients receiving central neuraxial block (CNB) for elective surgery. METHOD: One hundred patients of ASA grade I/II, aged 18-60 years undergoing elective surgery under CNB were enrolled. Ultrasound IVC examination was performed preoperatively and the patients were allocated to Group C (Collapsing group: IVCCI ≥50%) or Group NC (Non-Collapsing group: IVCCI <50%). Thereafter, in the operation theatre, the patient was given CNB and observed for development of hypotension. The hypotension was treated with additional fluid bolus (5 mL kg-1 over 10 minutes) and/or vasopressor (mephentramine 6 mg IV). The primary objective was to compare the incidence of hypotension; the secondary objective was to compare the fluid and vasopressor requirement in the Groups C and NC. RESULT: Six patients were excluded from study due to poor visualization of IVC. The mean IVCCI for Group C (n = 53) was 56.06 ± 4.62% and Group NC (n = 41) was 34.01 ± 8.94%. The incidence of hypotension was 56.60% (20/53) in Group C and 4.87% (2/41) in Group NC (P < .001). The vasopressor and fluid requirement was also statistically significantly higher in Group C compared with Group NC (P < .001). CONCLUSION: Preoperative ultrasound assessment of IVCCI is useful in predicting hypotension after CNB in patients receiving CNB for elective surgery.

Artificial Intelligence (AI) versus POCUS Expert: A Validation Study of Three Automatic AI-Based, Real-Time, Hemodynamic Echocardiographic Assessment Tools.

BACKGROUND: Point Of Care Ultra-Sound (POCUS) is an operator dependent modality. POCUS examinations usually include 'Eyeballing' the inspected anatomical structure without conducting accurate measurements due to complexity and insufficient time. Automatic real time measuring tools can make accurate measurements fast and simple and dramatically increase examination reliability while saving the operator much time and effort. In this study we aim to assess three automatic tools which are integrated into the Venue™ device by GE: the automatic ejection fraction, velocity time integral, and inferior vena cava tools in comparison to the gold standard-an examination by a POCUS expert. METHODS: A separate study was conducted for each of the three automatic tools. In each study, cardiac views were acquired by a POCUS expert. Relevant measurements were taken by both an auto tool and a POCUS expert who was blinded to the auto tool's measurement. The agreement between the POCUS expert and the auto tool was measured for both the measurements and the image quality using a Cohen's Kappa test. RESULTS: All three tools have shown good agreement with the POCUS expert for high quality views: auto LVEF (0.498; p < 0.001), auto IVC (0.536; p = 0.009), and the auto VTI (0.655; p = 0.024). Auto VTI has also shown a good agreement for medium quality clips (0.914; p < 0.001). Image quality agreement was significant for the auto EF and auto IVC tools. CONCLUSIONS: The Venue™ show a high agreement with a POCUS expert for high quality views. This shows that auto tools can provide reliable real time assistance in performing accurate measurements, but do not reduce the need of a good image acquisition technique.

The effect of ultrasound monitoring of inferior vena cava collapse index guiding fluid replacement on circulation in elderly patients during induction of general anesthesia / 中国医师杂志

Objective:To investigate the effect of ultrasound monitoring of inferior vena cava collapse index (IVC-CI) guiding fluid replacement on circulation in elderly patients during induction of general anesthesia.Methods:A total of 71 elderly patients who underwent elective surgery under general anesthesia and tracheal intubation at Hunan Provincial People′s Hospital from April 2021 to September 2022 were randomly divided into control group (35 cases) and observation group (36 cases) using a random number table method. Before anesthesia, both groups of patients underwent IVC ultrasound examination and calculated the IVC-CI value. For patients with IVC-CI≥40%, the observation group was given 8 ml/kg of crystal solution before anesthesia induction, while the control group was not treated. The incidence of hypotension, the use of vasoactive drugs, and the total infusion volume from anesthesia induction to skin incision were recorded in two groups. Mean arterial blood pressure (MBP), heart rate (HR), oxygen saturation (SpO 2), cardiac index (CI), and cardiac volume variability (SVV) before anesthesia (T 0), 5 min after induction (T 1), 1 min after tracheal intubation (T 2), 5 min after tracheal intubation (T 3), 10 min after tracheal intubation (T 4), and 1 min before skin incision (T 5) were recorded and compared between the two groups. Results:The incidence of hypotension (27.8% vs 60.0%) and utilization rate of vasoactive drugs (25.0% vs 48.6%) in the observation group were lower than those in the control group, and the total infusion volume during anesthesia induction was higher than that in the control group, with statistical significance (all P<0.05). SVV, CI and MBP at T 1, T 3, T 4 and T 5 were significantly different from those at T 0 in the control group ( F=3.85, 14.66, 3.96, all P<0.05). SVV, CI and MBP at T 1, T 3, T 4 and T 5 in the observation group were significantly different from those at T 0 ( F=3.51, 13.20, 4.35, all P<0.05). There was no significant difference in SVV, CI, MBP, HR and SpO 2 between 2 groups (all P>0.05). Conclusions:For the elderly patients with preoperative IVC-CI≥40%, pre-filling with 8ml/kg crystal solution before anesthesia induction can significantly reduce the incidence of hypotension and the utilization rate of vasoactive drugs in the elderly patients during anesthesia induction.

Ultrasound-guided estimation of internal jugular vein collapsibility index in patients with shock in emergency department.

OBJECTIVE: To correlate ultrasound-guided estimation of Internal Jugular Vein Collapsibility Index (IJV-CI) with inferior vena cava CI (IVC-CI) and invasively monitored central venous pressure (CVP) in patients with shock in the emergency medicine department. METHODS: A prospective observational study was done in the emergency department (ED). The study was conducted over 15 months (November 2019 to April 2021). It included patients more than 18 years presenting to the ED in shock. The IJV and IVC diameter and cross-sectional area were measured using ultrasound. The corresponding collapsibility indexes were then calculated and correlated with the invasively monitored CVP of the patient. Data were then analyzed using the Statistical Package for the Social Science (SPSS): Version 23 for windows. Pearson's correlation was used between CVP and collapsibility indexes. RESULTS: The mean (±standard deviation) age of the patients was 49.01 (±15.6). There was a 47 (64%) male predominance which outnumbered females 26 (36%). The correlation coefficient was statistically significant between CVP and the collapsibility indices for various IJV and IVC parameters. The highest correlation (r = -0.541, P = 0.005) was seen between IVC-CI (CI 5) and CVP. This was followed by a correlation seen at a 30° position for IJV CI (cross-sectional area) with CVP (r = -0.453, P = 0.001). Similarly, the correlation between IJV CI (AP diameter) and CVP, followed (r = -0.412, P = 0.008) was statistically significant. CONCLUSION: Both IJV and IVC collapsibility indices correlated significantly with invasively measured CVP. Hence, they present as an effective tool in fluid resuscitation in patients with shock in ED.

Clinical utility of ultrasonography, pulse oximetry and arterial line derived hemodynamic parameters for predicting post-induction hypotension in patients undergoing elective craniotomy for excision of brain tumors - A prospective observational study.

Background: Hypotension, which is a common adverse effect of induction of anesthesia, may be especially detrimental in neurosurgical patients. Hence, it is important to investigate hemodynamic parameters which may be useful in identifying patients at risk of hypotension, following induction. Our study was designed to assess the utility of parameters derived from ultrasonography, pulse oximeter and arterial line for predicting post-induction hypotension. Methods: The study was designed as a prospective, observational trial. Written informed consent was obtained from 100 American Society of Anesthesiologists (ASA) 1 and 2 patients, between 18-60 years of age, scheduled for elective craniotomy for brain tumors. Arterial cannula was inserted before induction of anesthesia and connected to Vigileo cardiac output monitor. Baseline stroke volume variation (SVV), stroke volume (SV), cardiac index (Ci), cardiac output (CO) and pulse pressure variation (PPV) were recorded. Plethysmography variability index (PVI) and perfusion index (PI) were obtained from the Masimo rainbow SET® Radical-7® pulse oximeter. Ultrasonographic assessment of the inferior vena cava (IVC) was performed before induction of anesthesia and again within 15 min after induction. Maximum and minimum IVC diameters (dIVCmax and dIVCmin) and collapsibility index (CI) were measured. All the other aforementioned parameters were recorded every minute starting at induction, until the 15th minute following induction. Results: PI, CI and dIVCmax were found to have the largest AUCROC for the prediction of post-induction hypotension (AUCROC 0.852, 0.823 and 0.781 respectively). Multiple logistic regression analysis revealed CI to be the most significant independent factor for the prediction of post-induction hypotension. Conclusion: Non-invasively derived hemodynamic parameters like dIVCmax, CI and PI were more accurate for the prediction of post-induction hypotension, compared to invasively derived parameters.

Can Ultrasound-Guided Femoral Vein Measurements Predict Spinal Anesthesia-Induced Hypotension in Non-Obstetric Surgery? A Prospective Observational Study.

Background and objectives: To investigate whether ultrasound (US)-guided femoral vein (FV) and inferior vena cava (IVC) measurements obtained before spinal anesthesia (SA) can be utilized to predict SA-induced hypotension (SAIH) and to identify risk factors associated with SAIH in patients undergoing non-obstetric surgery under SA. Methods: This was a prospective observational study conducted between November 2021 and April 2022. The study included 95 patients over the age of 18 with an American Society of Anesthesiologists (ASA) physical status score of 1 or 2. The maximum and minimum diameters of FV and IVC were measured under US guidance before SA initiation, and the collapsibility index values of FV and IVC were calculated. Patients with and without SAIH were compared. Results: SAIH was observed in 12 patients (12.6%). Patients with and without SAIH were similar in terms of age [58 (IQR: 19-70) vs. 48 (IQR: 21-71; p = 0.081) and sex (males comprised 63.9% of the SAIH and 75.0% of the non-SAIH groups) (p = 0.533). According to univariate analysis, no significant relationship was found between SAIH and any of the FV or IVC measurements. Multiple logistic regression analysis revealed that having an ASA class of 2 was the only independent risk factor for SAIH development (p = 0.014), after adjusting for age, sex, and all other relevant parameters. Conclusions: There is not enough evidence to accept the feasibility of utilizing US-guided FV or IVC measurements to screen for SAIH development in patients undergoing non-obstetric surgery under SA. For this, multicenter studies with more participants are needed.

Preoperative Ultrasonographic Evaluation of Subclavian Vein and Inferior Vena Cava for Predicting Hypotension Associated with Induction of General Anesthesia.

Introduction: Induction of general anesthesia is often associated with hypotension and is a common scenario faced by anesthesiologists. Intraoperative hypotension can have detrimental effects and cause various adverse effects leading to an extended hospital stay. Patients' preinduction volume status can have an effect on postinduction blood pressure. Ultrasonography is a useful tool for measuring intravascular volume status. We studied the ability of ultrasonographic measurement of subclavian vein (SCV) and inferior vena cava (IVC) diameter, collapsibility index (CI) to predict hypotension after induction of general anesthesia. Materials and Methods: We included 120 patients in our study. SCV measurements during spontaneous and deep inspiration and IVC measurements were taken before induction and postinduction blood pressure was monitored. Patients with mean arterial blood pressure <60 mmHg or with a 30% decrease from baseline were considered to be having hypotension. Results: The CI of IVC with a cutoff 37% showed sensitivity of 94% and specificity of 84% which was statistically significant. The CI of 36% of SCV during deep breathing was found to have high sensitivity and specificity of 90% and 87%. Conclusion: Our study in spontaneously breathing preoperative patients shows that SCV CI in deep breathing and IVC CI is very sensitive and reliable in predicting postinduction hypotension. Bedside ultrasound measurements can be easily done to obtain valuable information to recognize patients who could be at risk from postinduction hypotension.