Collapsibility Index Research Articles

Evaluation of Inferior Vena Cava Collapsibility Index as a Predictor of Hypotension Following General Anaesthesia with Thiopentone Induction: An Observational Study

Introduction: Hypotension during surgery can significantly increase morbidity and mortality. Volume depletion poses a major risk for intraoperative hypotension. The role of the Inferior Vena Cava Collapsibility Index (IVCCI) in assessing volume status is crucial, but its utility in predicting hypotension after the induction of general anaesthesia has been less evaluated. Aim: To evaluate the usefulness of IVCCI in predicting postinduction hypotension after general anaesthesia, with the primary objective being to assess the correlation between IVCCI and hypotension. Materials and Methods: An observational study was conducted in the Department of Anaesthesiology and Critical Care, Pt. B.D. Sharma, PGIMS, Rohtak, Haryana,India. Total 100 patients scheduled for elective surgery under general anaesthesia with thiopentone induction. IVCCI was measured preoperatively in spontaneously breathing patients. The patients were grouped into CI+ (Collapsible) and CI- (Non collapsible) groups based on IVCCI values of ≥ 50% and ≤ 50%, respectively. Haemodynamic parameters were recorded for up to one hour after anaesthesia induction. Hypotension was defined as a fall of more than 20% in Systolic Blood Pressure (SBP) or SBP <90 mmHg or a mean blood pressure of <60 mm Hg. Receiver Operating Characteristic (ROC) curve was used to evaluate the performance of IVCCI, and multivariate logistic regression was employed to identify predictors of hypotension. Independent t-test was used for quantitative associations, while Chi-square and Fisher’s-exact test were used for qualitative associations, with a p-value <0.05 considered significant. Results: The mean age of the patients in the study was 42.11±12.6 years. Out of 100, total 44 patients experienced post-induction hypotension, which was significantly higher in females compared to males (p-value=0.02). The mean Basal Metabolic Index (BMI) of the study population was 21.2±3.06 kg/m2 , but hypotension was more common in underweight patients with a BMI <18.5 kg/ m2 (p-value=0.0007). The results showed a significant correlation between IVCCI and hypotension (p-value<0.05). The mean value of IVCCI (%) was 47.34±6.96 in hypotensive patients, which was significantly higher than non hypotensive patients with a mean of 28.45±7.05 (%) (p-value<0.0001). The ROC curve demonstrated an excellent representation of IVCCI (%) (Area Under the ROC Curve (AUC) 0.944; 95% CI: 0.879 to 0.980) in predicting hypotension, with a sensitivity of 95.5% and specificity of 94.6% for hypotension. IVCCI (%) was a significant independent risk predictor of hypotension with a cut-off point of >38, as determined by performing multivariate logistic regression. Conclusion: Preoperative assessment of IVCCI is highly sensitive and specific for prediction hypotension induced by general anaesthesia. It is recommended as a screening tool for high-risk patients.

Co-existence of Obstructive and Septic Shock in a Patient Identified by Point of Care Ultrasonography: A Case Report

Shock is a state of acute circulatory failure leading to decreased organ perfusion, inadequate delivery of oxygenated blood to tissues, and resultant end-organ dysfunction. A 45-year-old male patient a known case of Diabetes Mellitus (DM) presented to the Emergency Room (ER) with a complaint of fever for four days and shortness of breath for one day. The patient had a wound discharging pus over the dorsum of the right foot for two weeks following trauma. On examination, the patient’s vitals were: pulse rate-88 Beats Per Minute (bpm), respiratory rate-26 breaths per minute, SpO2 -78% room air, Blood Pressure (BP)-82/40 mmHg mean arterial pressure- 54 mmHg. As a protocol of shock evaluation, Point Of Care Ultrasonography (POCUS) showed a distended Inferior Vena Cava (IVC), dilated right atrium and ventricle, and good left ventricular systolic function. Given the presence of right leg swelling, ultrasound was done, which showed a thrombus in the popliteal vein. Noradrenaline infusion was started to maintain a mean arterial blood pressure of 70 mmHg. A diagnosis of obstructive shock due to pulmonary embolism was strongly suspected, and thrombolysis with injection streptokinase was done. After two hours of thrombolysis, Two-Dimensional (2D) Echocardiography (ECHO) revealed normal right atrium and ventricle size and IVC collapsibility index of 70%, but the patient’s blood pressure didn’t improve significantly. So, adequate intravenous fluid was given as per the septic shock protocol. But, the noradrenalin requirement didn't improve. The patient was put on broad-spectrum antibiotics. Blood culture showed growth of Pseudomonas aeruginosa. So, a diagnosis of co-existing septic shock with obstructive shock was made. The patient improved and discharged in stable condition. The present case report highlights the co-existence of septic shock and obstructive shock and the usefulness of POCUS in differentiating and managing various shocks.

Application of Routine Echocardiography Combined with Contrast-Enhanced Echocardiography in the Diagnosis of Endomyocardial Fibrosis.

In China, endomyocardial fibrosis (EMF) is a type of restrictive cardiomyopathy that is rare and easy to be misdiagnosed. Our aim was to examine the value of routine echocardiography (RE) combined with contrast-enhanced echocardiography (CEE) in EMF diagnosis. We studied 16 EMF patients retrospectively, from 2012 to 2022. All patients underwent RE, from which 11 underwent CEE. We divided the patients into three groups: biventricular EMF (Bi-EMF), right ventricular EMF (RV-EMF), and left ventricular EMF (LV-EMF) based on different lesion locations. We also analyzed the clinical and conventional ultrasound characteristics of the three groups of patients and examined the ventricle opacification (VO) and myocardial contrast echocardiography (MCE) characteristics of patients who underwent CEE. All patients with EMF subtypes had the following ultrasound findings: apical occlusion on one or both sides, corresponding atrial dilatation, atrioventricular valve regurgitation in varying degrees, and cardiac diastolic dysfunction. Of the subjects, 69% had apical thrombus calcification and 81% had mild pericardial effusion. RV-EMF patients had statistically significant right atrial enlargement compared with the other two groups (p < 0.05), moderate or severe tricuspid regurgitation, and inferior vena cava (IVC) dilation. LV-EMF patients had statistically significant left atrial enlargement compared with the other two groups (p < 0.05), elevated pulmonary artery systolic pressure (PASP), and 60% of LV-EMF patients had moderate or severe mitral regurgitation. Bi-EMF patients had bilateral atrial enlargement, an IVC collapsibility index <50%, and elevated PASP. CEE was performed in 11 patients, whose ventricle opacification showed no contrast filling in the apical occluded area and the heart chambers presented the "mushroom sign" during diastole. Their myocardial contrast echocardiography (MCE) showed delayed perfusion in the thickened fibrotic endomyocardium (TFE) of the apical and subvalvular regions and perfusion defect in the apical thrombus. The number and location of thrombus determined by the MCE combined with RE were the same as those detected by cardiac magnetic resonance imaging (CMR). MCE shows that the position and range of TFE are similar to CMR. EMF has characteristic RE presentation, and different EMF subtypes have unique characteristics. CEE can better display heart structure, ventricular wall motion, and tissue perfusion compared to RE. A combination of RE and CEE can make the EMF diagnosis more accurate, thereby allowing early treatment for EMF patients.

Caudal vena cava measurements and fluid responsiveness in hospitalized cats with compromised hemodynamics and tissue hypoperfusion.

To evaluate the use of the caudal vena cava collapsibility index (CVCCI) and the inspiratory/minimum and expiratory/maximum diameters of the vena cava to predict fluid responsiveness in hospitalized, critically ill cats with hemodynamic and tissue perfusion abnormalities. Diagnostic test study in a prospective cohort of hospitalized cats. Private practice referral hospital. Twenty-four hospitalized cats with spontaneous breathing and compromised hemodynamics and tissue hypoperfusion. Ultrasonographic examination before and after fluid expansion with 10ml/kg of lactated Ringer's solution. Fluid responsiveness was evaluated using the velocity-time integral (VTI) of the subaortic blood flow, by measuring it before and after a fluid load of 10ml/kg of lactated Ringer's solution. The CVCCI was calculated using the following formula: (maximum diameter-minimum diameter / maximum diameter)×100. Ten cats were fluid responders (42 %) and 14 were nonresponders (58 %). The area under the receiver operating characteristic curve (AUROC) with their 95% confidence interval for the predictors and the best cutoff values were as follows: CVCCI, AUROC=0.83 (0.66-1.00) and cutoff=31%; inspiratory/minimum diameter, AUROC=0.86 (0.70-1.00) and cutoff=0.24cm; expiratory/maximum diameter, AUROC=0.88 (0.74-1.00) and cutoff=0.22cm. A significant lineal correlation was observed between the percentage of increase in VTI after expansion and CVCCI (rs =0.68, P<0.001), expiratory/maximum diameter (rs =-0.72, P<0.001), and inspiratory/minimum diameter (rs =-0.71, P<0.001). The intraobserver and interobserver variability was low for VTI, and the expiratory/maximum diameter and inspiratory/minimum diameter were high for CVCCI. Caudal vena cava measurements could be useful to predict the response to fluids in hospitalized cats with hemodynamic and tissue perfusion alterations. Additional studies are required to draw definitive conclusions about the role of these variables to guide fluid administration in cats.

The effect of short-course point-of-care echocardiography training on the performance of medical interns in children.

Point-of-care ultrasound (POCUS) can add complementary information to physical examination. Despite its development in several medical specialties, there is a lack of similar studies on children by medical interns and cardiologists. Therefore, investigators aimed to assess the effect of short-course training on the performance of medical interns in point-of-care echocardiography in children. This analytic cross-sectional study was conducted on 161 hospitalized children in 17 Shahrivar children's hospital, Iran, from January 2021 to May 2021. Seven interns (trainees) participated in a short course of point-of-care echocardiography to assess left ventricular ejection fraction (LVEF), inferior vena cava collapsibility index (IVCCI), and the presence of pericardial effusion (PEff). Each patient underwent point-of-care echocardiography by one of the trainees. Then, in less than one hour, the echocardiography was performed by a single cardiologist. Agreement between the cardiologist and trainees was examined using Cohen's kappa coefficient and Prevalence-Adjusted Bias-Adjusted Kappa (PABAK). For numerical variables, the agreement was examined using the concordance correlation coefficient (CCC) and intraclass correlation coefficient (ICC). Results showed that the cardiologist and trainees detected LVEF >50, IVCCI >50%, and the absence of PEff in most of the participants. A good agreement in terms of ICC and CCC for LVEF (0.832 and 0.831, respectively) and a good agreement in terms of ICC and CCC for IVCCI (0.878 and 0.877, respectively) were noted. Using categorical scoring of LVEF and IVCCI showed 94.4% and 87.6% complete agreement, respectively. Furthermore, using categorical scoring of LVEF and IVCCI, Cohen's kappa coefficient was 0.542 (moderate) and 0.619 (substantial), respectively. The PABAK for LVEF and IVCCI were 0.886 (almost perfect) and 0.752 (substantial), respectively. For PEff, Cohen's kappa and PABAK were 0.797 (moderate) and 0.988 (almost perfect), respectively, and the complete agreement was noted in 160 patients (99.4%). This study showed that a short teaching course could help medical interns to assess LVEF, IVCCI, and PEff in children. Therefore, it seems that adding this course to medical interns' curricula can be promising.

Correlation between non-invasive to invasive right-heart data in paediatric heart transplant patients.

Paediatric studies have shown serum N-terminal pro b-type natriuretic peptide levels to be a valuable tool in the surveillance of myocardial function and an early biomarker for rejection in transplant patients. The correlation between low mean right atrial pressure and increased inferior vena cava collapsibility index is well studied in adults. Our study aims to assess correlation between non-invasive measurements (serum N-terminal pro b-type natriuretic peptide, inferior vena cava dimensions collapsibility, tricuspid regurgitation, and left ventricular remodelling index to invasive mean right atrial pressure in paediatric heart transplant patients). A single centre, retrospective chart review of the paediatric transplant patients from 0 to 21 years of age was performed between 2015 and 2017. Thirty-nine patients had complete data which includes cardiac catheterisation, transthoracic echocardiogram, and serum N-terminal pro b-type natriuretic peptide levels done within a two weeks of interval. A higher inferior vena cava collapsibility index correlated with a lower mean right atrial pressure (r = -0.21, p = 0.04) and a larger inferior vena cava diameter in expiration indexed to body surface area (IVCmax/BSA0.5) correlated with a higher mean right atrial pressure (r = 0.29, p = 0.01). There was a correlation between elevated N-terminal pro b-type natriuretic peptide and inferior vena cava collapsibility index (r = -0.38, p = 0.0001), IVCmax/BSA0.5 (r = 0.25, p = 0.0002), and mean right atrial pressure (r = 0.6, p = 0.0001). Serum N-terminal pro b-type natriuretic peptide levels correlated to non-invasive measurements (inferior vena cava collapsibility index and IVCmax/BSA0.5) and to the invasive mean right atrial pressure. Non-invasive (IVC-CI IVCmax/BSA0.5) correlates with elevated mean right atrial pressure in this population. Together, these may serve as a reliable surveillance tool in assessing right heart filling pressures and cardiac function within the paediatric heart transplant patient.

ROLE OF ULTRASONOGRAPHIC INFERIOR VENACAVAL ASSESSMENT IN SURGERIES CONDUCTED UNDER GENERAL ANAESTHESIA-A PROSPECTIVE OBSERVATIONAL STUDY

Background: One of the most frequent side effects following the induction of general anaesthesia during surgery is hypotension. The goal of our study was to determine if there was a connection between the maximum inferior vena cava (IVC) diameter prior to induction, the collapsibility index (CI), and the post-induction decrease in mean arterial blood pressure in patients undergoing operations under general anaesthesia. Materials and Methods: Eighty patients who underwent procedures under general anaesthesia at Gandhi Medical College Bhopal and associated tertiary care hospital were included in a prospective observational research. Prior to starting general anaesthesia, the IVC was evaluated. For each surgical patient, the maximum and minimum IVC diameters (IVCD max and IVCD min) as well as the CI were assessed. Results: According to the criteria of hypotension as defined, 31(38.75%) of the patients developed post-induction hypotension. Four patients had MAP &lt;60 mmHg after induction of anesthesia. Post-induction hypotension was seen in patients with increased age. Patients with smaller IVCD max (P = 0.02), smaller IVCD min (P = 0.003), and higher CI% (P = 0.004) developed hypotension after induction of anesthesia. Percentage drop in MAP was 33.7 ± 4.48% (P = 0.002) in patients who developed post-induction hypotension. Conclusion: Predicting post-induction hypotension caused by hypovolemia in surgical patients with IVC measurement using ultrasound is a reliable strategy.

O057 Effects of oral appliance therapy on upper airway collapsibility pre- versus post-treatment

Abstract Introduction A key predictive mechanism of improvement in obstructive sleep apnoea (OSA) severity with oral appliance therapy (OAT) is a less collapsible upper airway. In this study, we investigate the effects of acute versus longer-term use of OAT on upper airway collapsibility. Methods To investigate potential changes in upper airway collapsibility we studied 10 treatment naïve people (2 female) with OSA (AHI=40±31events/h, age=51±11years, BMI=29±4kg/m-2) at baseline and following 4-6 weeks oral appliance therapy acclimatization. The upper airway collapsibility index was measured during wakefulness with/without the oral appliance in place at two time points (pre/post treatment). All participants were instrumented with standard polysomnography equipment, two pressure catheters (one at the level of the choanae, and the other at the epiglottis), a pneumotachograph, sealed nasal mask and a short tubing connected to a breathing circuit to allow rapid delivery of negative pressure ~-11cmH₂O to the mask. Results The upper airway collapsibility index measured during early inspiration was reduced by 11% (33±19 vs. 22±16%, n=10, p=0.02) with OAT in place in treatment naïve participants. Similarly, following acclimatization, the upper airway collapsibility index also reduced by 7% with OAT in place (25±15 vs. 18±15%, n=9, p=0.03). Conclusions While further work is required to determine if long-term OAT independently improves upper airway collapsibility, these data show sustained improvements in upper airway collapsibility with OAT over time and highlight the potential for this approach to help predict OAT treatment outcomes.

Intravascular volume status and stress markers in patients observing long and short duration of fasting: A prospective single blinded observational study

BackgroundPreoperative fasting may lead to intravascular volume depletion and this volume depletion may be a cause of perioperative stress. This study intends to compare the levels of stress markers in patients undergoing long and short duration fasting before an elective laparoscopic surgery. MethodThis was a single blind, observational study. Based on the duration of fasting, 70 ASA I and II category patients undergoing elective laparoscopic cholecystectomy(LC) were divided into two groups of 35 patients each. If the surgeon had prescribed a fasting since midnight then patient was considered for inclusion in Long fasting (LF) group; if surgeon had allowed clear fluids till 2 h before surgery then the patient was considered for inclusion in the short fasting(SF) group. The extent of intravascular volume depletion was measured using inferior vena cava collapsibility index (IVCCI). Levels of relevant stress markers i.e. cortisol, Tetraiodothyronine (FT4), C-peptide, C-reactive protein(CRP) and blood glucose (BGL) were measured at 8 PM in the night before surgery, at 7 AM on the day of surgery, 2 h after the surgery and 24 h after the surgery. ResultIVCCI was significantly more in the LF group; 27.66 ± 3.34% vs17.83 ± 2.22%, 95% CI 8.47–11.18, P-value <0.001). IVCCI had a significant correlation with the duration of fasting, Pearson's correlation r = 0.69,P-value <0.001. Repeated measures ANCOVA revealed that CRP, Free T4 and C-peptide levels got significantly elevated over the study duration, P-values <0.001,<0.001 and 0.03 respectively but with IVCCI, Age and Gender as the covariates, the increase in the levels of CRP, Free T4 and C-peptide were similar in both the groups. ConclusionStress markers levels show significant elevation in the perioperative period, maximum over the study duration, but this change is similar in both the groups.Clinical Trial No. CTRI/2021/02/031456

Biological impact of restrictive and liberal fluid strategies at low and high PEEP levels on lung and distal organs in experimental acute respiratory distress syndrome.

Background: Fluid regimens in acute respiratory distress syndrome (ARDS) are conflicting. The amount of fluid and positive end-expiratory pressure (PEEP) level may interact leading to ventilator-induced lung injury (VILI). We therefore evaluated restrictive and liberal fluid strategies associated with low and high PEEP levels with regard to lung and kidney damage, as well as cardiorespiratory function in endotoxin-induced ARDS. Methods: Thirty male Wistar rats received an intratracheal instillation of Escherichia coli lipopolysaccharide. After 24h, the animals were anesthetized, protectively ventilated (VT = 6ml/kg), and randomized to restrictive (5ml/kg/h) or liberal (40ml/kg/h) fluid strategies (Ringer lactate). Both groups were then ventilated with PEEP = 3 cmH2O (PEEP3) and PEEP = 9 cmH2O (PEEP9) for 1h (n = 6/group). Echocardiography, arterial blood gases, and lung mechanics were evaluated throughout the experiments. Histologic analyses were done on the lungs, and molecular biology was assessed in lungs and kidneys using six non-ventilated animals with no fluid therapy. Results: In lungs, the liberal group showed increased transpulmonary plateau pressure compared with the restrictive group (liberal, 23.5 ± 2.9 cmH2O; restrictive, 18.8 ± 2.3cmH2O, p = 0.046) under PEEP = 9 cmH2O. Gene expression associated with inflammation (interleukin [IL]-6) was higher in the liberal-PEEP9 group than the liberal-PEEP3 group (p = 0.006) and restrictive-PEEP9 (p = 0.012), Regardless of the fluid strategy, lung mechanical power and the heterogeneity index were higher, whereas birefringence for claudin-4 and zonula-ocludens-1 gene expression were lower in the PEEP9 groups. Perivascular edema was higher in liberal groups, regardless of PEEP levels. Markers related to damage to epithelial cells [club cell secreted protein (CC16)] and the extracellular matrix (syndecan) were higher in the liberal-PEEP9 group than the liberal-PEEP3 group (p = 0.010 and p = 0.024, respectively). In kidneys, the expression of IL-6 and neutrophil gelatinase-associated lipocalin was higher in PEEP9 groups, regardless of the fluid strategy. For the liberal strategy, PEEP = 9 cmH2O compared with PEEP = 3 cmH2O reduced the right ventricle systolic volume (37%) and inferior vena cava collapsibility index (45%). Conclusion: The combination of a liberal fluid strategy and high PEEP led to more lung damage. The application of high PEEP, regardless of the fluid strategy, may also be deleterious to kidneys.

Feasibility of Very Early Identification of Cardiogenic Shock by Semi-automated Ultrasound Exam in the Emergency Department.

Background Cardiogenic shock (CS) is critical end-organ hypoperfusion due to reduced cardiac output. Early therapy, such as vasoactive agents or the initiation of mechanical circulatory support (MCS), requires early diagnosis and is associated with better outcomes. A novel ultrasound platform (GE Healthcare, Milwaukee, WI) has semi-automated imaging software (SAIS), which could simplify the point-of-care ultrasound (POCUS) diagnosis of CS. We assessed the feasibility of using POCUS with SAIS in patients in shock, determined the ability of SAIS to identify the subset of patients with CS, and described the process and outcome of care of patients with vs. without CS after presenting to Emergency Department (ED) with hypotension. Methods This prospective case-control study was conducted at an urban ED. Physicians with prior POCUS education received one hour of training with the study device. The qualitative ejection fraction was determined by visual assessment. SAIS measurements of hemodynamics were made with the study device and included left ventricle outflow tract velocity time integral (LVOT VTI), inferior vena cava collapsibility or distensibility indices, and pulmonary B-line assessment.ED patients with a systolic blood pressure ≤ 90 mmHg or need for a vasopressor initiation in the ED were enrolled. The diagnosis of CS was determined by a medical record review. All data were summarized descriptively. Results Twenty-ninecases underwent POCUS, and 87 controls did not. Baseline characteristics, process, and outcome of care were similar between groups. Seventy-nine percent (79%) of cases had a complete POCUS with SAIS. Of these, 55% had reduced LVOT VTI, 38% had IVC collapsibility <50%, and 48% of cases had a B-line pattern consistent with pulmonary edema. The mean LVOT VTI for cases with CS was 9.4± 5.4 cm; the mean LVOT VTI for cases without CS was 15.2 ± 6.0 cm. Among patients who did not undergo POCUS, 31 (36%) had a formal echocardiogram, and eight (9%) had a final diagnosis of cardiogenic shock during hospitalization. Conclusion Physicians with one hour of platform-specific training were able to implement POCUS with SAIS among patients who present with shock. POCUS with SAIS may aid in the early recognition of CS.

Evaluation of ultrasonography measurement of superior vena cava diameter in comparison to central venous pressure in guiding of fluid therapy in patients with hypovolemic shock

Invasive placement of a central venous catheter is the norm for measuring central venous pressure (CVP), which is essential in perioperative care (CVC). Clinical evaluation of the jugular venous pressure allows for a non-invasive estimation of CVP. Superior vena cava (SVC) diameter and collapsibility with breathing have been emphasised in echocardiographic estimates of CVP. The goal of this study is to compare CVP values to ultrasound measurements of SVC diameter and collapsibility index in directing fluid treatment for patients with hypovolemic shock. On admission, patients underwent hemodynamic monitoring of intravascular volume by measuring central venous pressure, taking a non-invasive blood pressure reading, and calculating urine output. Additionally, SVC ultrasonography was used to determine the diameter and collapsibility of the saphenous vein. Conclusions Patients with a central venous pressure (CVP) of 10 or higher had substantially greater values for their SVC maximum and minimum, and smaller values for their SVC coefficient of variation (CI). There was a positive association between CVP and maximum and minimum dSVC, and a negative correlation between CVP and SVC-CI. The optimal SVC-CI cutoff for separating patients with and without CVP10 was 36%, with a sensitivity of 27% and a specificity of 87.5 %. Independent predictors of CVP10 were shown to be lower SVC-CI, which aided in the decision to discontinue fluid infusion. Overall, the CVP is still the gold standard for guiding fluid resuscitation in the critically unwell. Estimating CVP non-invasively by measuring SVC diameter and collapsibility during positive pressure breathing seems intriguing. Predicting high CVP using SVC-CI might help you decide when to stop giving the patient fluids.

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

BackgroundHypotension, 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. MethodsThe 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. ResultsPI, 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. ConclusionNon-invasively derived hemodynamic parameters like dIVCmax, CI and PI were more accurate for the prediction of post-induction hypotension, compared to invasively derived parameters.

Lung ultrasound as an evolving tool in the detection of extravascular lung water following goal-directed fluid therapy in septic cancer patients

Background: Severe sepsis can result in septic shock with a high mortality rate. This study aimed to assess the correlation between B-lines detected by lung ultrasound (LUS) and thoracic fluid content (TFC) and to compare their sensitivity and specificity to predict lung congestion on conventional chest radiograph following early goal-directed fluid therapy in septic cancer patients.&#x0D; Methods: This study included 30 patients suffering from sepsis admitted to the intensive care unit. They received resuscitation according to the surviving sepsis campaign 2018 guidelines. Lung ultrasonography, TFC, central venous pressure (CVP), and inferior vena cava (IVC) scanning were done upon admission then after 3, 6, and 12 h. Chest X-ray was done after 6 h then at the study end (12 h) and CT chest at 12 h.&#x0D; Results: B-lines showed a moderate-to-strong positive correlation with TFC, a moderate and positive correlation with CVP, and a negative and weak-to-moderate correlation with IVC collapsibility index. The performance of LUS was good at 6 h (AUC = 0.872, 95% CI = 0.700 to 0.965, P &lt; 0.001), and the optimal cut-off value was 7 with a sensitivity and specificity of 75% and 95.5%, respectively. The sensitivity and specificity increased to reach 100% at 12 h using a cut-off value of 9. Meanwhile TFC had lower AUCs compared to B-lines at the two-time points though the difference was statistically non-significant.&#x0D; Conclusion: Lung ultrasound can be considered a useful non-invasive bedside tool for early detection of extravascular lung water during the early resuscitation phase of goal-directed fluid therapy in sepsis patients.&#x0D; Abbreviations: LUS: Lung ultrasound; EVLW: Extravascular Lung Water; TFC: Thoracic fluid content; CVP: Central venous pressure; IVC: Inferior vena cava; AUC: Area under the curve; PAOP: Pulmonary artery occlusion pressure; IVC-CI: Inferior vena cava collapsibility index&#x0D; Citation: Elsabeeny WY, Ibrahim MA, El Desouky ED, Hamed M, Shaker EH. Lung ultrasound as an evolving tool in the detection of extravascular lung water following goal-directed fluid therapy in septic cancer patients. Anaesth. pain intensive care 2022;26(5):623-632; DOI: 10.35975/apic.v26i5.1987

Guidance of Ultrasound in Critical Illness to Direct Euvolemia Trial: A Cluster-Randomized, Crossover, Comparative Effectiveness Trial

INTRODUCTION: Acute kidney injury (AKI) after trauma is common and associated with poor outcomes. Both inadequate resuscitation and excess fluid administration increase incidence and duration of AKI. We hypothesized that adding ultrasound (US) assessments of inferior vena cava diameter and collapsibility index to usual care would result in shorter AKI duration. METHODS: The Guidance of Ultrasound in Critical Illness to Direct Euvolemia (GUIDE) trial was a sequential, cluster-randomized, crossover comparative effectiveness trial designed to account for care team clusters. ICU teams were randomized to usual care with or without the addition of 24 hours of serial inferior vena cava diameter and inferior vena cava diameter and collapsibility index measurements from September 2019 to June 2020. The primary outcome was AKI duration. Univariate and multivariate analyses were performed. RESULTS: Of 411 patients, 222 were randomized to the US group. Demographics were similar between groups. Patients had a median Injury Severity Score of 26 (interquartile range 16 to 34) and a median age of 38 (interquartile range 26 to 60). The incidence of AKI was similar between groups (US 54% vs usual care 58%, p = 0.46), and the median duration of AKI was 1 day in both groups (interquartile range 0 to 2, p = 0.34). Fluid balances were similar at 24 hours; however, at 48 hours, patients in the US group had a higher fluid balance (Figure). Other complications and mortality were similar between groups.FigureCONCLUSION: This comparative effectiveness trial demonstrated that addition of inferior vena cava diameter and inferior vena cava diameter and collapsibility index assessments to routine care did not affect the duration of AKI but increased patients’ fluid balance at 48 hours. Routine application of US assessments of fluid status in severely injured trauma patients is not recommended.

Maximum inferior vena cava diameter predicts post-induction hypotension in hypertensive patients undergoing non-cardiac surgery under general anesthesia: A prospective cohort study.

BackgroundInferior vena cava (IVC) ultrasonography is a reliable variable that predicts post-induction hypotension (PIH) in patients undergoing surgery under general anesthesia. However, in patients with hypertension, the predictive performance of ultrasound IVC measurements needs further exploration.MethodsThis is a prospective cohort study. Adult patients with existing hypertension scheduled to undergo non-cardiac surgery under general anesthesia were eligible. An abdominal ultrasound examination was conducted immediately prior to anesthesia induction (0.03 mg kg–1 midazolam, 0.3 mg kg–1 etomidate, 0.4 μg kg–1 sufentanil, and 0.6 mg kg–1 rocuronium). IVC collapsibility index (IVC-CI) was calculated as (dIVCmax–dIVCmin)/dIVCmax, where dIVCmax and dIVCmin represent the maximum and minimum IVC diameters at the end of expiration and inspiration, respectively. PIH was defined as a reduction of mean arterial pressure (MAP) by >30% of the baseline or to <60 mmHg within 10 min after endotracheal intubation. The diagnostic performance of IVC-CI, dIVCmax, and dIVCmin in predicting PIH was also examined in a group of normotensive patients receiving non-cardiac surgery under the same anesthesia protocol.ResultsA total of 51 hypertensive patients (61 ± 13 years of age, 31 women) and 52 normotensive patients (42 ± 13 years of age, 35 women) were included in the final analysis. PIH occurred in 33 (64.7%) hypertensive patients and 19 (36.5%) normotensive patients. In normotensive patients, the area under the receiver operating curve (AUC) in predicting PIH was 0.896 (95% confidence interval [CI]: 0.804–0.987) for IVC-CI, 0.770 (95% CI: 0.633–0.908) for dIVCmax, and 0.868 (95% CI: 0.773–0.963) for dIVCmin. In hypertensive patients, the AUC in predicting PIH was 0.523 (95% CI: 0.354–0.691) for IVC-CI, 0.752 (95% CI: 0.621–0.883) for dIVCmax, and 0.715 (95% CI: 0.571–0.858) for dIVCmin. At the optimal cutoff (1.24 cm), dIVCmax had 54.5% (18/33) sensitivity and 94.4% (17/18) specificity.ConclusionIn hypertensive patients, IVC-CI is unsuitable for predicting PIH, and dIVCmax is an alternative measure with promising performance.Clinical trial registration[http://www.chictr.org.cn/], identifier [ChiCTR2000034853].

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

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. 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. 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. 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.

Evaluation of the Effect of Interscalene Brachial Plexus Block on Intracranial Pressure Using Optic Nerve Sheath Diameter and Internal Jugular vein Collapsibility Index.

To determine the effect of single-shot interscalene brachial plexus (ISBP) block on intracranial pressure (ICP) by evaluating the extravascular volume effect of the medicine on the internal jugular vein (IJV). Interventional study. Department of Anaesthesiology and Reanimation, Sivas Cumhuriyet University, Sivas, Turkey, from January to June 2022. Thirty-four patients were included in this prospective clinical study. All patients had single-shot ISBP block with 25 ml of local anaesthetic. Optic nerve sheath diameter (ONSD), maximum (Dmax) and minimum (Dmin) diameters of IJV and IJV collapsibility index (IJV-CI) were recorded before the block (basal), 20 minutes, and 60 minutes after the block. Twenty-nine patients had higher ONSD values at 60th minute compared to their basal values. There were negative correlations between the changes of ONSD and IJVCI (r=0.616, p<0.001) and ONSD and Dmax (r=0.581, p<0.001) in time period between basal and 20th minute. There were negative correlations between the changes of ONSD and IJVCI (r=0.518, p=0.002), ONSD and Dmax (r=0.664, p<0.001) in time period between basal and 60th minute. Single-shot ISBP block with 25 ml of local anaesthetic may be a factor that increases ICP. Repeated intraoperative ONSD measurements are recommended in patients operated with ISBP block. Interscalene Brachial Plexus Block, Intracranial pressure, Optic nerve sheath diameter, Internal jugular vein collapsibility index.

Assessment of Ultrasonographic Measurement of Inferior Vena Cava Collapsibility Index in The Prediction of Hypotension Associated with Tourniquet Release in Total Knee Replacement Surgeries under Spinal Anesthesia

Assessment of Ultrasonographic Measurement of Inferior Vena Cava Collapsibility Index in The Prediction of Hypotension Associated with Tourniquet Release in Total Knee Replacement Surgeries under Spinal Anesthesia

Correlation of preoperative inferior vena cava diameter and inferior vena cava collapsibility index with preoperative fasting status, patient demography and general anaesthesia associated hypotension: A prospective, observational study.

A definitive cutoff of inferior venacava (IVC) diameter in expiration (dIVCmax) and inferior vena cava collapsibility index (IVCCI) for predicting general anaesthesia associated hypotension (GAAH) is not yet determined. Primary objective of this study was to determine the correlation of dIVCmax and IVCCI, with GAAH. Other objectives were to determine the correlation of these IVC parameters with preoperative fasting duration, temperature and humidity. The correlation of dIVCmax with patient demography was also studied. A total of 110 adult patients undergoing elective surgery under general anaesthesia were included in the study. IVC ultrasonography was done in the preoperative room, 20 to 30 minutes before shifting the patient to the operating room. Hypotension at (hypo@) 2 minutes and 10 minutes after administering vecuronium was recorded. Hundred and seven patients were analysed. A significant positive correlation was present between patient height and dIVCmax (r = 0.25, P = 0.009). Area under receiver operating characteristics curve was 0.595 (95% confidence interval (CI) 0.485-0.705) and 0.568 (95% CI 0.458-0.679) for dIVCmax and IVCCI for predicting hypo@2 min, with a diagnostic accuracy of 54% and 53%, respectively. dIVCmax ≤1.14 cm had a sensitivity of 31% and specificity of 87% in predicting GAAH. IVCCI ≥63.3% could predict GAAH with 31% sensitivity and 84% specificity. No significant correlation was found between preoperative IVC parameters and preoperative fasting or environmental factors. Both dIVCmax and IVCCI have poor diagnostic accuracy, with good specificity and low sensitivity in predicting GAAH. A steady formula for calculating baseline IVC diameter adjusted for patient demography is needed.