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Background: The rapid identification of acute stroke (AS) during and after anesthesia might lead to early interventions and improved outcomes. We investigated a novel 2-channel electroencephalogram (EEG)-based marker for stroke detection-the lateral interconnection ratio (LIR)-in AS patients having endovascular thrombectomy (EVT) with general anesthesia (GA) or sedation. The LIR in 2 reference groups of patients without postoperative neurological complications was used for comparison., Methods: The National Institutes of Health stroke scale score was assessed before and after thrombectomy in 100 patients having EVT with GA or sedation. The EEG was monitored during and for 4 hours following EVT in the AS group and during surgery in the 2 reference groups. We compared: (1) LIR between AS and reference groups; (2) LIR and stroke dynamics (clinical improvement or deterioration after EVT assessed by the National Institutes of Health stroke scale score); (3) the impact of stroke site (anterior vs. posterior circulation) and anesthesia type (GA vs. sedation) on the LIR., Results: Median (interquartile range) LIR was lower in patients with AS compared with reference patients (0.09, 0.05 to 0.16 vs. 0.39, 0.24 to 0.52, respectively; P <0.000002), and LIR increased in AS patients whose clinical status recovered after EVT compared with nonrecovered patients (0.20, 0.12 to 0.29 vs. 0.09, 0.05 to 0.11, respectively; P <0.007). The LIR might be more sensitive to anterior circulation stroke but is not impacted by anesthesia type., Conclusions: We demonstrated the utility of using AS patients undergoing EVT as a platform for assessing a novel EEG marker for the identification of stroke during anesthesia. Further, large-scale studies in AS patients during EVT and in patients undergoing different surgeries and anesthesia are required to validate the LIR., Competing Interests: G.S. and D.B.S. are spouses. GS founded several companies in the field of EEG analysis (including, over the last decade, BrainMARC Ltd and NeuroIndex Ltd), and DBS consulted NeuroIndex Ltd. For more than 2 years G.S. and D.B.S are not actively involved with any of these companies. The present study is not related to these companies and their technology. It is based on subsequent developments in GS academic laboratory at Rambam Health Care Campus. The remaining authors have no conflict of interest to declare., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Valvular heart disease can be an important finding in patients presenting for noncardiac surgery. Valvular heart disease and resulting comorbidity, such as heart failure or atrial fibrillation, significantly increase the risk for perioperative adverse events. Appropriate preoperative assessment, adequate perioperative monitoring, and early intervention, should hemodynamic disturbances occur, may help prevent adverse events and improve patient outcome. This review article aims to guide the practitioner in the various aspects of anesthetic management in the perioperative care of patients with valvular heart disease. The pharmacological approach to optimization of patient outcome with drugs, such as betablockers and lipid-lowering medications (statins), is an evolving field, and recent developments are discussed in this article.

Transesophageal echocardiography (TEE) provides high-resolution images of the mitral valve apparatus, permitting detailed evaluation of its structure and function. Mitral valve evaluation is invaluable during mitral valve repair surgery, providing insight into the mechanism of valve dysfunction and formulation of a plan for repair. TEE provides immediate detection of inadequate repair after bypass and allows correction during the same operative setting. Intraoperative TEE is a valuable tool for improving patient outcome and offers the cardiovascular anesthesiologist a role in perioperative surgical decisions.

Aortic disease is a serious, often life-threatening condition. The keys to instituting appropriate therapy in diseases of the aorta include accurate and rapid diagnosis and anatomical assessment. Endovascular aortic repair is a new alternative to conventional surgical approaches. Because arterial rupture is a risk of this procedure, appropriate facilities for resuscitation must be present during the procedure. This paper reviews the important aspects of aortic anatomy, echocardiographic imaging of the thoracic aorta, aortic pathology, endovascular surgery, and the role of echocardiography in the evaluation of the surgical outcome.

Background: Postoperative atrial fibrillation in coronary artery bypass graft surgery occurs in 10-40% of patients. It is associated with a significant degree of morbidity and results in prolonged lengths of stay in both the intensive care unit and hospital., Methods: The authors prospectively evaluated patients undergoing coronary artery bypass with detailed transesophageal echocardiography examinations conducted before and after cardiopulmonary bypass to study whether risk factors for atrial fibrillation could be identified. Demographic and surgical parameters were also included in the analysis. Selected variables were subjected to univariate and subsequent multivariate analyses to test for their independent or joint influence on atrial fibrillation., Results: Seventy-nine patients had assessable transesophageal echocardiography examinations. Significant univariate predictors of atrial fibrillation included advanced age (P = 0.002), pre-cardiopulmonary bypass left atrial appendage area (P = 0.04), and post-cardiopulmonary bypass left upper pulmonary vein systole/diastole velocity ratio (P = 0.03). When these three factors were considered together in a multiple logistic regression analysis, left upper pulmonary vein systole/diastole velocity ratio was a significant predictor (P < 0.05), as was the joint effect of age plus pre-cardiopulmonary bypass left atrial appendage area (P = 0.005). The probability of developing atrial fibrillation for the combination of age = 75 yr, post-cardiopulmonary bypass left upper pulmonary vein systole/diastole velocity ratio = 0.5, and left atrial appendage area = 4.0 cm was 0.83 (95% confidence interval, 0.51-0.96)., Conclusions: Early identification of patients at risk for postoperative atrial fibrillation may be feasible using the parameters identified in this study.

Unlabelled: Hextend (BioTime, Inc., Berkeley, CA) is a new plasma volume expander containing 6% hetastarch, balanced electrolytes, a lactate buffer, and physiological levels of glucose. In preclinical studies, its use in shock models was associated with an improvement in outcome compared with alternatives, such as albumin or 6% hetastarch in saline. In a prospective, randomized, two-center study (n = 120), we compared the efficacy and safety of Hextend versus 6% hetastarch in saline (HES) for the treatment of hypovolemia during major surgery. Patients at one center had a blood sample drawn at the beginning and the end of surgery for thromboelastographic (TEG) analysis. Hextend was as effective as HES for the treatment of hypovolemia. Patients received an average of 1596 mL of Hextend: 42% received >20 mL/kg up to a total of 5000 mL. No patient received albumin. Hextend-treated patients required less intraoperative calcium (4 vs 220 mg; P < 0.05). In a subset analysis of patients receiving red blood cell transfusions (n = 56; 47%), Hextend-treated patients had a lower mean estimated blood loss (956 mL less; P = 0.02) and were less likely to receive calcium supplementation (P = 0.04). Patients receiving HES demonstrated significant prolongation of time to onset of clot formation (based on TEG) not seen in the Hextend patients (P < 0.05). No Hextend patient experienced a related serious adverse event, and there was no difference in the total number of adverse events between the two groups. The results of this study demonstrate that Hextend, with its novel buffered, balanced electrolyte formulation, is as effective as 6% hetastarch in saline for the treatment of hypovolemia and may be a safe alternative even when used in volumes up to 5 L., Implications: Hextend (BioTime, Inc., Berkeley, CA) is a new plasma volume expander containing 6% hetastarch, balanced electrolytes, a lactate buffer, and a physiological level of glucose. It is as effective as 6% hetastarch in saline for the treatment of hypovolemia but has a more favorable side effects profile in volumes of up to 5 L compared with 6% hetastarch in saline.

Introduction: Pediatric patients undergoing prolonged periods of deep hypothermic circulatory arrest have been found to experience long-term deficits in cognitive function. However, there is limited information of this type in adult patients who are undergoing deep hypothermic circulatory arrest for thoracic aortic repairs., Methods: One hundred forty-nine patients undergoing elective cardiac or thoracic aortic operations were evaluated preoperatively; 106 patients were evaluated early in the postoperative period (EARLY), and 77 patients were evaluated late in the postoperative period (LATE) with a battery of neuropsychologic tests. Seventy-three patients had routine cardiac operations without deep hypothermic circulatory arrest, and 76 patients with deep hypothermic circulatory arrest were divided into 2 subgroups: those with 1 to 24 minutes of deep hypothermic circulatory arrest (n = 36 patients) and those with 25 minutes or more of deep hypothermic circulatory arrest (n = 40 patients). The neuropsychologic test battery consisted of 8 tests encompassing 5 domains: attention, processing speed, memory, executive function, and fine motor function. Data were normalized to baseline values, and changes from baseline were analyzed by analysis of covariance, multivariate logistic regression, and survival functions., Results: In all domains, poor performance or inability to be tested EARLY were significant predictors of poor performance LATE (odds ratio, 5.27; P <.01). Deep hypothermic circulatory arrest of 25 minutes or more and advanced age were significant predictors of poor performance LATE for the memory and fine motor domains. Deep hypothermic circulatory arrest of 25 minutes or more (odds ratio, 4. 0; P =.02) was a determinant of prolonged hospital stay (>21 days)., Conclusion: Deep hypothermic circulatory arrest of 25 minutes or more and advanced age were associated with memory and fine motor deficits and with prolonged hospital stay.

Objectives: To define the utility of intraoperative transeophageal echocardiography (TEE) during endovascular thoracic aortic repair., Design: Retrospective study., Materials: Five patients underwent six transluminal endovascular stent-graft procedures for repair of thoracic aortic disease., Methods: After induction of anaesthesia, a multiplane or biplane TEE probe was placed to obtain views of the diseased aorta. Both transverse and longitudinal planes of the aortic arch and descending thoracic aortic segments were imaged. The aortic pathology was confirmed by TEE and the proximal and distal extents of the intrathoracic lesion were defined. Doppler and colour-flow imaging was used to identify flow patterns through the aorta before and after stent-graft deployment., Results: Visualisation and confirmation of the aortic pathology by ultrasonography was accomplished in all patients. TEE was able to confirm proper placement of the endograft relative to the aortic lesion after deployment and was able to confirm exclusion of blood flow into the aneurysm sacs., Conclusions: TEE may facilitate repair by confirming aortic pathology, identifying endograft placement, assessment of the adequacy of aneurysm sack isolation, as well as dynamic intraoperative cardiac assessment.

Purpose: Cisatracurium besylate (Nimbex Injection, Glaxo Wellcome Inc., Research Triangle Park, NC) is an intermediate-acting bis-benzylisoquinolinium neuromuscular blocking drug that is one of the stereoisomers of atracurium. At doses < or = 8 x ED95, it caused no clinically important cardiovascular side effects or histamine release in healthy patients. The purpose of the present study was to investigate the haemodynamic effects of high doses of cisatracurium in patients with coronary artery disease., Methods: One hundred patients undergoing myocardial revascularization participated in a pilot study (seven patients) and a double-blinded, randomized, controlled trial comparing the haemodynamic effects of cisatracurium with vecuronium at three centres. The patients were anaesthetized using oxygen 100%, with etomidate, fentanyl and a benzodiazepine, and tracheal intubation was facilitated using succinylcholine. After baseline haemodynamic measurements, the study drug was administered over 5-10 sec according to group assignment: Group A (pilot) cisatracurium, 0.20 mg.kg-1 (4 x ED95), (n = 7); Group B-cisatracurium, 0.30 mg.kg-1 (6 x ED95), (n x ED95), (n = 31); Group C-vecuronium, 0.30 mg.kg-1 (6 x ED95), (n = 31); Group D cisatracurium, 0.40 mg.kg-1 (8 x ED95), (n = 21); Group E-vecuronium, 0.30 mg.kg-1 (6 x ED95), (n = 10). The haemodynamic measurements were repeated at 2, 5, and 10 min after cisatracurium or vecuronium., Results: Two patients in Group D had > 20% decreases in MAP, but only one required therapy for hypotension. The haemodynamic changes from pre- to post-injection in the cisatracurium patients were minimal and similar to patients receiving vecuronium., Conclusions: In patients with coronary artery disease, rapid cisatracurium (4-8 x ED95) boluses and vecuronium (6 x ED95) result in minor, clinically insignificant haemodynamic side effects.