Carotid blood flow changes following a simulated end-inspiratory occlusion maneuver measured by ultrasound can predict hypotension after the induction of general anesthesia: an observational study.

BACKGROUND: The primary purpose of this study was to investigate the predictive value of alterations in cervical artery hemodynamic parameters induced by a simulated end-inspiratory occlusion test (sEIOT) measured by ultrasound for predicting postinduction hypotension (PIH) during general anesthesia. METHODS: Patients undergoing gastrointestinal tumor resection under general anesthesia were selected for this study. Ultrasound has been utilized to assess hemodynamic parameters in carotid artery blood flow before induction, specifically focusing on variations in corrected flow time (ΔFTc) and peak blood flow velocity (ΔCDPV), both before and after sEIOT. Anesthesia was induced by midazolam, sufentanil, propofol, and rocuronium, and blood pressure (BP) and heart rate (HR) were recorded within the first 10 min following endotracheal intubation. PIH was defined as fall in systolic blood pressure (SBP) or mean arterial pressure (MAP) by > 30% of baseline or MAP to < 60 mm Hg. RESULTS: The area under the receiver operating characteristic curves (AUC) for carotid artery ΔFTc was 0.88 (95%CI, 0.81 to 0.96; P < 0.001), and the optimal cutoff value was -16.57%, with a sensitivity of 91.4% and specificity of 77.60%. The gray zone for carotid artery ΔFTc was -16.34% to -15.36% and included 14% of the patients. The AUC for ΔCDPV was 0.54, with an optimal cutoff value of -1.47%. The sensitivity and specificity were calculated as 55.20% and 57.10%, respectively. CONCLUSION: The corrected blood flow time changes in the carotid artery induced by sEIOT can predict hypotension following general anesthesia-induced hypotension, wherein ΔFTc less than 16.57% is the threshold. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( www.chictr.org.cn ; 20/06/2023; ChiCTR2300072632).

SHoC-IVC: Does assessment of the inferior vena cava by point-of-care ultrasound independently predict fluid status in spontaneously breathing patients with undifferentiated hypotension?

BACKGROUND: Accurately determining the fluid status of a patient during resuscitation in the emergency department (ED) helps guide appropriate fluid administration in the setting of undifferentiated hypotension. Our goal was to determine the diagnostic utility of point-of-care ultrasound (PoCUS) for inferior vena cava (IVC) size and collapsibility in predicting a volume overload fluid status in spontaneously breathing hypotensive ED patients. METHODS: This was a post hoc secondary analysis of the SHOC-ED data, a prospective randomized controlled trial investigating PoCUS in patients with undifferentiated hypotension. We prospectively collected data on IVC size and collapsibility for 138 patients in the PoCUS group using a standard data collection form, and independently assigned a fluid status (volume overloaded, normal, volume deplete) from a composite clinical chart review blinded to PoCUS findings. The primary outcome was the diagnostic performance of IVC characteristics on PoCUS in the detection of a volume overloaded fluid status. RESULTS: One hundred twenty-nine patients had completed determinant IVC assessment by PoCUS, with one hundred twenty-five receiving successful final fluid status determination, of which one hundred and seven were classified as volume deplete, thirteen normal, and seven volume overloaded. A receiver operating characteristic (ROC) curve was plotted using several IVC size and collapsibility categories. The best overall performance utilized the combined parameters of a dilated IVC (> 2.5 cm) with minimal collapsibility (less than 50%) which had a sensitivity of 85.7% and specificity of 86.4% with an area under the curve (AOC) of 0.92 for predicting an volume overloaded fluid status. CONCLUSION: IVC PoCUS is feasible in spontaneously breathing hypotensive adult ED patients, and demonstrates potential value as a predictor of a volume overloaded fluid status in patients with undifferentiated hypotension. IVC size may be the preferred measure.

RéSUMé: CONTEXTE: La détermination précise de l'état du liquide d'un patient pendant la réanimation au service des urgences (SU) aide à guider l'administration appropriée du liquide dans le cadre d'une hypotension indifférenciée. Notre objectif était de déterminer l'utilité diagnostique de l'échographie au point de soins (PoCUS) pour la taille de la veine cave inférieure (IVC) et l'collapsibilité dans la prédiction d'un état de liquide de surcharge volumique chez les patients souffrant d'une hypotension respiratoire spontanée. MéTHODES: Il s'agissait d'une analyse secondaire post-hoc des données SHOC-ED, un essai contrôlé randomisé prospectif examinant PoCUS chez des patients atteints d'hypotension indifférenciée. Nous avons collecté prospectivement des données sur la taille et la collapsibilité des IVC pour 138 patients du groupe PoCUS à l'aide d'un formulaire de collecte de données standard, et attribué indépendamment un état de fluide (volume surchargé, normal, épuisement du volume) à partir d'une revue de dossier clinique composite mise en aveugle aux résultats PoCUS. Le résultat principal était la performance diagnostique des caractéristiques IVC sur PoCUS dans la détection d'un état de fluide surchargé en volume. RéSULTATS: 129 patients avaient terminé l'évaluation IVC des déterminants par PoCUS, dont 125 ont reçu une détermination finale du statut hydrique, dont 107 ont été classés comme étant une diminution du volume, 13 normaux et 7 surchargés. Une courbe des caractéristiques de fonctionnement du récepteur (ROC) a été tracée en utilisant plusieurs catégories de taille et d'affaissement IVC. La meilleure performance globale a utilisé les paramètres combinés d'une IVC dilatée (> 2,5 cm) avec une collapsibilité minimale (moins de 50%) qui avait une sensibilité de 85,7% et une spécificité de 86,4% avec une zone sous la courbe (AOC) de 0,92 pour prédire un état de fluide surchargé en volume. CONCLUSION: IVC PoCUS est faisable chez les patients adultes souffrant d'une hypotension respiratoire spontanée et démontre une valeur potentielle en tant que prédicteur d'un état de liquide surchargé en volume chez les patients atteints d'hypotension indifférenciée. La taille IVC peut être la mesure préférée.

Exploring the predictive value of combined ultrasound parameters for spinal anesthesia-induced hypotension in cesarean section: a prospective observational study.

BACKGROUND: Prophylactic vasopressor infusion can effectively assist with fluid loading to prevent spinal anesthesia-induced hypotension. However, the ideal dose varies widely among individuals. We hypothesized that hypotension-susceptible patients requiring cesarean section (C-section) could be identified using combined ultrasound parameters to enable differentiated prophylactic medical interventions. METHODS: This prospective observational trial was carried out within a regional center hospital for women and children in Sichuan Province, China. Singleton pregnant women undergoing combined spinal-epidural anesthesia for elective C-sections were eligible. Women with contraindications to spinal anesthesia or medical comorbidities were excluded. Velocity time integral (VTI) and left ventricular end-diastolic area (LVEDA) in the supine and left lateral positions were measured on ultrasound before anesthesia. Stroke volume, cardiac output, and the percentage change (%) in each parameter between two positions were calculated. Vital signs and demographic data were recorded. Spinal anesthesia-induced hypotension was defined as a mean arterial pressure decrease of > 20% from baseline. The area under the receiver operating characteristic curve (AUROC) was used to analyze the associations of ultrasound measurements, vital signs, and demographic characteristics with spinal anesthesia-induced hypotension. This exploratory study did not have a predefined outcome; however, various parameter combinations were compared using the AUROC to determine which combined parameters had better predictive values. RESULTS: Patients were divided into the normotension (n = 31) and hypotension groups (n = 57). A combination of heart rate (HR), LVEDAs, and VTI% was significantly better at predicting hypotension than was HR (AUROC 0.827 vs. 0.707, P = 0.020) or LVEDAs (AUROC 0.827 vs. 0.711, P = 0.039) alone, but not significantly better than VTI% alone (AUROC 0.827 vs. 0.766, P = 0.098). CONCLUSION: The combined parameters of HR and LVEDAs with VTI% may predict spinal anesthesia-induced hypotension more precisely than the single parameters. Future research is necessary to determine whether this knowledge improves maternal and neonatal outcomes. TRIAL REGISTRATION: ChiCTR1900025191.

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.

Does point-of-care ultrasonography improve diagnostic accuracy in emergency department patients with undifferentiated hypotension? An international randomized controlled trial from the SHOC-ED investigators.

PURPOSE: Point-of-care ultrasonography (POCUS) is an established tool in the management of hypotensive patients in the emergency department (ED). We compared the diagnostic accuracy of a POCUS protocol versus standard assessment without POCUS in patients with undifferentiated hypotension. METHODS: This was an international, multicenter randomized controlled trial included three EDs in North America and three in South Africa from September 2012 to December 2016. Hypotensive patients were randomized to early POCUS protocol plus standard care (POCUS group) or standard care without POCUS (control group). Initial and secondary diagnoses were recorded at 0 and 60 min. The main outcome was measures of diagnostic accuracy of a POCUS protocol in differentiating between cardiogenic and non-cardiogenic shock. Secondary outcomes were diagnostic performance for shock sub-types, as well as changes in perceived category of shock and overall diagnosis. RESULTS: Follow-up was completed for 270 of 273 patients. For cardiogenic shock, the POCUS-based diagnostic approach (POCUS) performed similarly to the non-POCUS approach (control) for specificity [95.5% (89.9-98.5) vs.93.8% (87.7-97.5)]; positive likelihood ratio (17.92 vs 14.80); negative likelihood ratio (0.21 vs 0.09) and diagnostic odds ratio (85.6 vs 166.57), with a similar overall diagnostic accuracy between the two approaches [93.7% (88-97.2) vs 93.6% (87.8-97.2)]. Diagnostic performance measures were similar across sub-categories of shock. CONCLUSION: This is the first randomized controlled trial to compare diagnostic performance of a POCUS protocol to standard care without POCUS in undifferentiated hypotensive ED patients. POCUS performed well diagnostically in undifferentiated hypotensive patients, especially as a rule-in test; however, performance did not differ meaningfully from standard assessment.

RéSUMé: OBJECTIF: L'échographie au point d'intervention (POCUS) est un outil bien établi dans la gestion des patients hypotendus dans le service des urgences. Nous avons comparé la précision diagnostique d'un protocole POCUS par rapport à une évaluation standard sans POCUS chez des patients présentant une hypotension indifférenciée. MéTHODES: Il s'agissait d'un essai contrôlé randomisé international multicentrique incluant 3 services d'urgence en Amérique du Nord et 3 en Afrique du Sud de septembre 2012 à décembre 2016. Les patients hypotenseurs ont été répartis par randomisation selon le protocole POCUS précoce plus les soins standard (groupe POCUS) ou les soins standard sans POCUS (groupe témoin). Les diagnostics initiaux et secondaires ont été enregistrés à 0 et 60 minutes. Le principal résultat était la mesure de la précision diagnostique d'un protocole POCUS pour différencier le choc cardiogénique du choc non cardiogénique. Les résultats secondaires étaient la performance diagnostique pour les sous-types de chocs, ainsi que les changements dans la perception de la catégorie de choc et du diagnostic global. RéSULTATS: Le suivi a été complété pour 270 des 273 patients. Pour le choc cardiogénique, l'approche diagnostique basée sur le POCUS (POCUS) a donné des résultats similaires à l'approche non-POCUS (Contrôle) pour la spécificité (95,5 % (89,9­98,5) vs 93,8 % (87,7­97,5)) ; Rapport de vraisemblance positif (17,92 vs 14,80) ; Le rapport de vraisemblance négatif (0,21 vs 0,09) et le rapport de cotes diagnostiques (85,6 vs 166,57), avec une précision diagnostique globale similaire entre les deux approches (93,7 % (88­97,2) vs 93,6 % (87,8­97,2). Les mesures de performance diagnostique étaient similaires dans toutes les sous-catégories de choc. CONCLUSION: Il s'agit du premier essai contrôlé randomisé visant à comparer la performance diagnostique d'un protocole POCUS aux soins standard sans POCUS chez des patients hypotendus indifférenciés aux urgences. La POCUS a donné de bons résultats diagnostiques chez les patients hypotendus indifférenciés, surtout en tant que test de référence ; cependant, les performances ne diffèrent pas de manière significative de l'évaluation standard.

Hypotension at Hospital Presentation and Post-Contrast Acute Kidney Injury following Computed Tomography with Contrast Media.

INTRODUCTION: Post-contrast acute kidney injury (PC-AKI) is a major complication of contrast media usage; risks for PC-AKI are generally evaluated before computed tomography (CT) with contrast at the emergency department (ED). Although persistent hypotension (systolic blood pressure [sBP] <80 mm Hg for 1 h) is associated with increased PC-AKI incidence, it remains unclear whether transient hypotension that is haemodynamically stabilized before CT is a risk of PC-AKI. We hypothesized that hypotension on ED arrival would be associated with higher PC-AKI incidence even if CT with contrast was performed after patients are appropriately resuscitated. METHODS: This multicentre retrospective observational study was conducted at three tertiary care centres during 2013-2014. We identified 280 patients who underwent CT with contrast at the ED. Patients were classified into two groups based on sBP on arrival (<80 vs. ≥80 mm Hg); hypotension was considered as transient because CT with contrast has always been performed after patients were stabilized at participating hospitals. PC-AKI incidence was compared between the groups; inverse probability weighting (IPW) was conducted to adjust background characteristics. RESULTS: Eighteen patients were excluded due to chronic haemodialysis, cardiac arrest on arrival, or death within 72 h; 262 were eligible for this study. PC-AKI incidence was higher in the transient hypotension group than the normotension group {7/27 (28.6%) vs. 24/235 (10.2%), odds ratio (OR) 3.08 (95% confidence interval [CI] 1.18-8.03), p = 0.026}, which was confirmed by IPW (OR 3.25 [95% CI 1.99-5.29], p < 0.001). CONCLUSION: Transient hypotension at the ED was associated with PC-AKI development.

Preoperative echocardiography predictive analytics for postinduction hypotension prediction.

PURPOSE: Hypotension is a risk factor for adverse perioperative outcomes. Preoperative transthoracic echocardiography has been extended for preoperative risk assessment before noncardiac surgery. This study aimed to develop a machine learning model to predict postinduction hypotension risk using preoperative echocardiographic data and compared it with conventional statistic models. We also aimed to identify preoperative echocardiographic factors that cause postinduction hypotension. METHODS: In this retrospective observational study, we extracted data from electronic health records of patients aged >18 years who underwent general anesthesia at a single tertiary care center between April 2014 and September 2019. Multiple supervised machine learning classification techniques were used, with postinduction hypotension (mean arterial pressure <55 mmHg from intubation to the start of the procedure) as the primary outcome and 95 transthoracic echocardiography measurements as factors influencing the primary outcome. Based on the mean cross-validation performance, we used 10-fold cross-validation with the training set (70%) to select the optimal hyperparameters and architecture, assessed ten times using a separate test set (30%). RESULTS: Of 1,956 patients, 670 (34%) had postinduction hypotension. The area under the receiver operating characteristic curve using the deep neural network was 0.72 (95% confidence interval (CI) = 0.67-0.76), gradient boosting machine was 0.54 (95% CI = 0.51-0.59), linear discriminant analysis was 0.56 (95% CI = 0.51-0.61), and logistic regression was 0.56 (95% CI = 0.51-0.61). Variables of high importance included the ascending aorta diameter, transmitral flow A wave, heart rate, pulmonary venous flow S wave, tricuspid regurgitation pressure gradient, inferior vena cava expiratory diameter, fractional shortening, left ventricular mass index, and end-systolic volume. CONCLUSION: We have created developing models that can predict postinduction hypotension using preoperative echocardiographic data, thereby demonstrating the feasibility of using machine learning models of preoperative echocardiographic data for produce higher accuracy than the conventional model.

Reliability of Pre-Induction Inferior Vena Cava Assessment with Ultrasound for the Prediction of Post-Induction Hypotension in Neurosurgical Patients Undergoing Intracranial Surgery.

Background: Hypotension is one of the most common complications following induction of general anesthesia. Preemptive diagnosis and correcting the hypovolemic status can reduce the incidence of post-induction hypotension. However, an association between preoperative volume status and severity of post-induction hypotension has not been established in neurosurgical patients. We hypothesized that preoperative ultrasonographic assessment of intravascular volume status can be used to predict post-induction hypotension in neurosurgical patients. Our study objective was to establish the relationship between pre-induction maximum inferior vena cava (IVC) diameter, collapsibility index (CI), and post-induction reduction in mean arterial blood pressure in neurosurgical patients. Materials and Methods: A prospective observational study was conducted including 100 patients undergoing elective intracranial surgeries. IVC assessment was done before induction of general anesthesia. Receiver operating characteristic (ROC) curve analysis was used to determine the cutoff values of maximum and minimum IVC diameter (IVCDmax and IVCDmin, respectively) and CI for prediction of hypotension. Results: Post-induction hypotension was observed in 41% patients. Patients with small IVCDmax and higher CI% developed hypotension. The areas under the ROC curve (AUCs) were 0.64 (0.53-0.75) for IVCDmax and 0.69 (0.59-0.80) for IVCDmin. The optimal cutoff values were1.38 cm for IVCDmax and 0.94 cm for IVCDmin. The AUC for CI was 0.65 (0.54-0.77) and the optimal cutoff value was 37.5%. Conclusion: Pre-induction IVC assessment with ultrasound is a reliable method to predict post-induction hypotension resulting from hypovolemia in neurosurgical patients.

POCUS in dyspnea, nontraumatic hypotension, and shock; a systematic review of existing evidence.

BACKGROUND: Point-of-care ultrasound (POCUS) has been adopted as a powerful tool in acute medicine. This systematic review aims to critically appraise the existing literature on point-of-care ultrasound in respiratory or circulatory deterioration. METHODS: Original studies on POCUS and dyspnea, nontraumatic hypotension, and shock from March 2002 until March 2022 were assessed in the PubMed and Embase Databases. Two reviewers independently screened articles for inclusion, extracted data, and assessed the quality of included studies using an established checklist. RESULTS: We included 89 articles in this review. Point-of-care ultrasound in the initial workup increases the diagnostic accuracy in patients with dyspnea, nontraumatic hypotension and shock in the ED, ICU and medical ward setting. No improvement is found in patients with severe sepsis in the ICU setting. POCUS is capable of narrowing the differential diagnoses and is faster, and more feasible in the acute setting than other diagnostics available. Results on outcome measures are heterogenous. The quality of the included studies is considered low most of the times, mainly because of performance and selection bias and absence of a gold standard as the reference test. CONCLUSION: We conclude that POCUS contributes to a higher diagnostic accuracy in dyspnea, nontraumatic hypotension, and shock. It aides in narrowing the differential diagnoses and shortening the time to correct diagnosis and effective treatment. TRIAL REGISTRY: INPLASY; Registration number: INPLASY202220020; URL: https://inplasy.com/.

Inferior vena cava ultrasonography before general anesthesia cannot predict arterial hypotension in patients undergoing vascular surgery.

INTRODUCTION: Intraoperative hypotension (IH) is an independent predictor of mortality. Some experts have suggested that ultrasound measurement of the inferior vena cava (IVC) in spontaneous ventilation can predict IH. OBJECTIVE: To evaluate the capacity of ultrasound measures of IVC in spontaneous ventilation to predict episodes of IH after anaesthesia induction. PATIENTS AND METHODS: We studied 55 high-risk cardiac patients undergoing vascular surgery. The maximum (dIVCmax) and minimum (dIVCmin) diameter of the IVC were measured and the collapsibility index CI = (dIVCmax-dIVCmin)/dIVCmax was calculated prior to anaesthesia induction. Three definitions of IH were used: systolic blood pressure (SBP) less than 100 mmHg, mean arterial pressure (MAP) less than 60 mmHg, and a decrease in MAP greater than or equal to 30% compared to baseline. RESULTS: There were no significant differences in dIVCmax or in CI between patients presenting IH after anaesthesia induction and those who did not. ROC curves for dIVCmax showed an area under the curve of 0.55 (0.39-0.70), 0.69 (0.48-0.90), and 0.57 (0.42-0.73) and ROC curves for the CI were 0.62 (0.47-0.78), 0.60 (0.41-0.78) and 0.62 (0.47-0.78) for the 3 definitions of IH (<100 mmHg, MAP < 60 mmHg, and MAP ≥30% baseline), respectively. CONCLUSIONS: Ultrasound measurements of IVC in spontaneous ventilation are not good predictors of IH after anaesthesia induction in these patients. The optimal cut-off points show low specificity and moderate sensitivity for predicting IH.

Diagnosis of bone cement implantation syndrome using point of care ultrasound examination.

Once regarded as a rare complication, the potentially fatal bone cement implantation syndrome (BCIS) has been increasingly reported. BCIS can present as transient desaturation, hypotension, cardiac dysrhythmias, and cardiovascular collapse. Diagnosis of BCIS is often clinical and confirmed with computed tomography (CT) imaging postoperatively. However, point of care ultrasound (POCUS) examination could be a helpful and timely tool to clinch the diagnosis in a sudden cardiovascular collapse. We present a case of Grade 3 BCIS where POCUS examination revealed a massive clot in the right atrium, which supports the diagnosis.

Ultrasound Hypotension Protocol Time-motion Study Using the Multifrequency Single Transducer Versus a Multiple Transducer Ultrasound Device.

INTRODUCTION: Ultrasound hypotension protocols (UHP) involve imaging multiple body areas, each with different transducers and imaging presets. The time for task switching between presets and transducers to perform an UHP has not been previously studied. A novel hand-carried ultrasound (HCU) has been developed that uses a multifrequency single transducer to image areas of the body (lung, heart, abdomen, superficial) that would typically require three transducers using a traditional cart-based ultrasound (CBU) system. Our primary aim was to compare the time to complete UHPs with a single transducer HCU to a multiple transducer CBU. METHODS: We performed a randomized, crossover feasibility trial in the emergency department of an urban, safety-net hospital. This was a convenience sample of non-hypotensive emergency department patients presenting during a two-month period of time. Ultrasound hypotension protocols were performed by emergency physicians (EP) on patients using the HCU and the CBU. The EPs collected UHP views in sequential order using the most appropriate transducer and preset for the area/organ to be imaged. Time to complete each view, time for task switching, total time to complete the examination, and image diagnostic quality were recorded. RESULTS: A total of 29 patients were scanned by one of eight EPs. When comparing the HCU to the CBU, the median time to complete the UHP was 4.3 vs 8.5 minutes (P <0.0001), respectively. When the transport and plugin times were excluded, the median times were 4.1 vs 5.8 minutes (P <0.0001), respectively. There was no difference in the diagnostic quality of images obtained by the two devices. CONCLUSION: Ultrasound hypotension protocols were performed significantly faster using the single transducer HCU compared to a multiple transducer CBU with no difference in the number of images deemed to be diagnostic quality.

OCT angiography metrics predict intradialytic hypotension episodes in chronic hemodialysis patients: a pilot, prospective study.

In chronic hemodialysis (HD) patients, intradialytic hypotension (IDH) is a complication that increases mortality risk. We run a pilot study to analyzing possible relationships between optical coherence tomography angiography (OCT-A) metrics and IDH with the aim of evaluating if OCT-A could represent a useful tool to stratify the hypotensive risk in dialysis patients. A total of 35 eyes (35 patients) were analyzed. OCT-A was performed before and after a single dialysis session. We performed OCT-A 3 × 3 mm and 6 × 6 mm scanning area focused on the fovea centralis. Patients were then followed up to 30 days (10 HD sessions) and a total of 73 IDHs were recorded, with 12 patients (60%) experiencing at least one IDH. Different OCT-A parameters were reduced after dialysis: central choroid thickness (CCT), 6 × 6 mm foveal whole vessel density (VD) of superficial capillary plexus (SPC) and 6 × 6 mm foveal VD of deep capillary plexus (DCP). At logistic regression analysis, IDH was positively associated with baseline foveal VD of SCP and DCP, while an inverse association was found with the choroid. In Kaplan-Meier analyses of patients categorized according to the ROC-derived optimal thresholds, CCT, the 3 × 3 foveal VD of SCP, the 3 × 3 mm and 6 × 6 mm foveal VD of DCP and the 6 × 6 mm foveal VD of SCP were strongly associated with a higher risk of IDH over the 30-days follow-up. In HD patients, a single OCT-A measurement may represent a non-invasive, rapid tool to evaluate the compliance of vascular bed to HD stress and to stratify the risk of IDH in the short term.

Prognosis of patients in prolonged coma after severe carbon monoxide poisoning.

BACKGROUND: Late recovery in patients following prolonged coma from carbon monoxide poisoning have been reported, but the probability is unclear. The purpose of this research was to assess the prognosis of patients in prolonged coma after severe carbon monoxide poisoning and related clinical and imaging features. METHODS: There were 13 patients who had been in a state of coma for >7 days after acute carbon monoxide poisoning in the retrospective observational study, and demographic data, clinical data, laboratory data, complications, and image data were collected. Outcome was assessed by means of the Glasgow outcome scale after 1 year. The relationship between complications and imaging manifestations and prognosis was also analyzed. RESULTS: One year after severe carbon monoxide poisoning, two patients (15.4%) had died (GOS 1), nine (69.2%) were in a persistent vegetative state (GOS 2), one (7.7%) was moderately disabled (GOS 4), and one (7.7%) achieved a good recovery (GOS 5) with minimal disability. CONCLUSIONS: Most patients with prolonged coma after severe carbon monoxide poisoning had a poor prognosis, although the younger patients had a better prognosis. Respiratory failure, hypotension and renal failure during the course of the disease were associated with a poor prognosis. The prognosis of patients with injuries in two sites in early CT was poor. Multiple lesions (≥3) and extensive white matter damage (Fazekas grade (PVH or DWMH) = 3) on MRI of chronic phase were also associated with a poor prognosis.

A dose-escalating toxicology study of the candidate biologic ELP-VEGF.

Vascular Endothelial Growth Factor (VEGF), a key mediator of angiogenesis and vascular repair, is reduced in chronic ischemic renal diseases, leading to microvascular rarefaction and deterioration of renal function. We developed a chimeric fusion of human VEGF-A121 with the carrier protein Elastin-like Polypeptide (ELP-VEGF) to induce therapeutic angiogenesis via targeted renal VEGF therapy. We previously showed that ELP-VEGF improves renal vascular density, renal fibrosis, and renal function in swine models of chronic renal diseases. However, VEGF is a potent cytokine that induces angiogenesis and increases vascular permeability, which could cause undesired off-target effects or be deleterious in a patient with a solid tumor. Therefore, the current study aims to define the toxicological profile of ELP-VEGF and assess its risk for exacerbating tumor progression and vascularity using rodent models. A dose escalating toxicology assessment of ELP-VEGF was performed by administering a bolus intravenous injection at doses ranging from 0.1 to 200 mg/kg in Sprague Dawley (SD) rats. Blood pressure, body weight, and glomerular filtration rate (GFR) were quantified longitudinally, and terminal blood sampling and renal vascular density measurements were made 14 days after treatment. Additionally, the effects of a single administration of ELP-VEGF (0.1-10 mg/kg) on tumor growth rate, mass, and vascular density were examined in a mouse model of breast cancer. At doses up to 200 mg/kg, ELP-VEGF had no effect on body weight, caused no changes in plasma or urinary markers of renal injury, and did not induce renal fibrosis or other histopathological findings in SD rats. At the highest doses (100-200 mg/kg), ELP-VEGF caused an acute, transient hypotension (30 min), increased GFR, and reduced renal microvascular density 14 days after injection. In a mouse tumor model, ELP-VEGF did not affect tumor growth rate or tumor mass, but analysis of tumor vascular density by micro-computed tomography (µCT) revealed significant, dose dependent increases in tumor vascularity after ELP-VEGF administration. ELP-VEGF did not induce toxicity in the therapeutic dosing range, and doses one hundred times higher than the expected maximum therapeutic dose were needed to observe any adverse signs in rats. In breast tumor-bearing mice, ELP-VEGF therapy induced a dose-dependent increase in tumor vascularity, demanding caution for potential use in a patient suffering from kidney disease but with known or suspected malignancy.

Carotid Ultrasound in Assessing Fluid Responsiveness in Patients with Hypotension and Suspected Sepsis.

PURPOSE: We sought to assess whether ultrasound (US) measurements of carotid flow time (CFTc) and carotid blood flow (CBF) predict fluid responsiveness in patients with suspected sepsis. METHODS: This was a prospective observational study of hypotensive (systolic blood pressure < 90) patients "at risk" for sepsis receiving intravenous fluids (IVF) in the emergency department. US measurements of CFTc and CBF were performed at time zero and upon completion of IVF. All US measurements were repeated after a passive leg raise (PLR) maneuver. Fluid responsiveness was defined as normalization of blood pressure without persistent hypotension or need for vasopressors. RESULTS: A convenience sample of 69 patients was enrolled. The mean age was 65; 49% were female. Fluid responders comprised 52% of the cohort. CFTc values increased significantly with both PLR (P = 0.047) and IVF administration (P = 0.003), but CBF values did not (P = 0.924 and P = 0.064 respectively). Neither absolute CFTc or CBF measures, nor changes in these values with PLR or IVF bolus, predicted fluid responsiveness, mortality, or the need for intensive care unit admission. CONCLUSION: In patients with suspected sepsis, a fluid challenge resulted in a significant change in CFTc, but not CBF. Neither absolute measurement nor delta measurements with fluid challenge predicted clinical outcomes.

Intraoperative Focused Cardiac Ultrasound for Assessment of Hypotension: A Systematic Review.

Focused cardiac ultrasound (FoCUS) has become a valuable tool to assess unexplained hypotension in critically ill patients. Due to increasing availability of transthoracic echocardiography (TTE) equipment in the operating room, there is a widespread interest in its usefulness for intraoperative diagnosis of hypotension as an alternative to transesophageal echocardiography (TEE). The objective of this systematic review is to evaluate the utility of intraoperative FoCUS to assess patients experiencing unexplained hypotension while undergoing noncardiac surgery. We performed a systematic literature search of multiple publication databases for studies that evaluated the utility of intraoperative FoCUS for assessment and management of unexplained hypotension in patients undergoing noncardiac surgery, including retro- and prospective clinical studies. A summary of the study findings, study quality, and assessment of level of evidence is presented. We identified 2227 unique articles from the literature search, of which 27 were potentially relevant, and 9 were included in this review. The number of patients pooled from these studies was 255, of whom 228 had intraoperative diagnoses with the aid of intraoperative FoCUS. The level of evidence of all studies included was very low according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) guidelines. This systematic review has demonstrated that FoCUS may be a useful, noninvasive method to differentiate causes of intraoperative hypotension and guide correcting interventions, although the quality of evidence is very low. Further prospective high-quality studies are needed to investigate whether intraoperative FoCUS has a diagnostic utility that is associated with improved outcomes.

Rapid Ultrasound for Shock and Hypotension: A Clinical Update for the Advanced Practice Provider: Part 1.

The Rapid Ultrasound for Shock and Hypotension (RUSH) examination is used for patients with hypotension without clear cause or undifferentiated hypotension. In the emergency department setting, clinicians may perform the RUSH examination to supplement the physical assessment and differentiate the diagnosis of hypovolemic, obstructive, cardiogenic, and distributive forms of shock. The key elements of the RUSH examination are the pump, tank, and pipes, meaning potentially causes of the hypotension are examined within the heart, vascular volume and integrity, and the vessels themselves. Clinicians follow a systemic protocol to seeking evidence of specific conditions including heart failure exacerbation, cardiac tamponade, pleural effusion, pneumothorax, abdominal aortic aneurysm, and deep vein thrombosis. Because ultrasonography is a user-dependent skill, the advanced practice nurse in the emergency department should be educated regarding the RUSH protocol and prepared to implement the examination.