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Background: Monitored anesthesia care (MAC) has become more widely used during transcatheter aortic valve replacement (TAVR) to avoid the complications of general anesthesia (GA)., Methods: We included consecutive patients who underwent transfemoral-TAVR at our institution between January 2012 and April 2017. We compared outcomes with GA versus MAC., Results: Of 998 patients, MAC was used in 43.9%. MAC was associated with shorter procedural time (96.9 ± 30.9 vs. 135 ± 64.6 mins; p < .001), fluoroscopy time (20.4 ± 8.9 vs. 29 ± 18.7 mins; p < .001), lower contrast volume (45.5 ± 27 vs. 60.4 ± 43 cc; p < .001), and decreased radiation exposure (12,869 ± 8,099 vs. 20,630 ± 16,276 cGy-cm 2 ; p < .001). Patients who underwent MAC had a briefer median (IQR) intensive care unit stay [23.3 (21-24) vs. 23.4 (20.8-26) hrs; p < .001], and hospital stay [2 (2, 3) vs. 3 (2-6) days; p < .001], and were more frequently discharged to home (93.4% vs. 82.9%; p < .001). MAC was associated with lower mortality at 30 days (0.5% vs. 2.9%; log-rank p = .012; adjHR 0.22, 95% CI 0.06-0.82; p = .024), but not at 1 year (11.7% vs. 14.6%; log-rank p = .157) or 3 years (36.8% vs. 38.4%; log-rank p = 0.433). There were no differences in major adverse cardiac and cerebrovascular events (MACCE) at either 30 days (4.6% vs. 9.3%; log-rank p = .14) or 1 year (21.1% vs. 21.5%; log-rank p = .653). Similar findings were seen among patients who received newer-generation SAPIEN-3 valves., Conclusion: Utilizing MAC and omitting intraprocedural transesophageal echocardiography during TAVR seems to be more efficient without compromising safety. Better TAVR outcomes can be achieved with newer generation valves without needing GA., (© 2021 Wiley Periodicals LLC.)

Intraoperative transesophageal echocardiography is a standard diagnostic and monitoring tool employed in the management of patients undergoing an entire spectrum of cardiac surgical procedures, ranging from "routine" surgical coronary revascularization to complex valve repair, combined procedures, and organ transplantation. Utilizing a protocol as a starting point for imaging in all procedures and all patients enables standardization of image acquisition, reduction in variability in quality of imaging and reporting, and ultimately better patient care. Clear communication of the echocardiographic findings to the surgical team, as well as understanding the impact of new findings on the surgical plan, are paramount. Equally important is the need for complete understanding of the technical steps of the surgical procedures being performed and the complications that may occur, in order to direct the postprocedure evaluation toward aspects directly related to the surgical procedure and to provide pertinent echocardiographic information. The rationale for this document is to outline a systematic approach describing how to apply the existing guidelines to questions on cardiac structure and function specific to the intraoperative environment in open, minimally invasive, or hybrid cardiac surgery procedures., (Copyright © 2020 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Point-of-care ultrasound (POCUS) is becoming an integral part of anesthesia practice throughout the world. Despite the growing interest in POCUS among trainees and faculty, POCUS training is variable among universities across Canada. This suggests a need for curriculum development and standardization. International guidelines for Emergency Medicine and Critical Care have common frameworks and may be used as a reference to model anesthesia-specific curricula. The Royal College of Anaesthetists of the United Kingdom currently offers the only nationally approved POCUS curriculum for anesthesia and critical care trainees. Most curricula have in common a stepwise approach that consists of foundation of knowledge and skills and competency building through practice. Nevertheless, a significant variety of didactic modalities have been described, and online learning and simulation offer clear advantages. What constitutes the minimum number of studies necessary to achieve competence is still debated as are the most appropriate tools for assessment of POCUS competency.Availability of trained staff anesthesiologists remains a major limitation to curricula implementation in most centres. A National Curriculum should be modeled on the Competency By Design Approach, in line with the CanMEDS 2015 roles, and start with a focus on basic POCUS modalities and applications. Guidance for the training and certification of POCUS among practicing anesthesiologists is lacking.

Endocardial motion and surface/volume changes during the cardiac cycle are echocardiographic methods for regional (analysis of wall motion) and global (fractional area change, stroke volume, and ejection fraction) evaluation of cardiac function. These conventional methods can be subjective, and/or time consuming and, depending upon circumstances, may divert the anesthesiologist's attention from intraoperative activities. Doppler tissue imaging (DTI) is a novel echocardiographic technique, which displays and measures systolic and diastolic velocity from a myocardial region. DTI is simple to perform and independent of adequate endocardial imaging. The numeric information (velocity or time intervals) is easily obtained and measured. Assessment of systolic and diastolic function on regional (detection of ischemia) as well as global level (ejection fraction, grading of diastolic dysfunction) and evaluation of filling pressure can be derived from DTI signals and used by any practicing cardiac anesthesiologist. This review describes the principles, imaging modalities, and clinical applications of DTI.

Objective: Epicardial, beating heart cryoablation for the treatment of atrial fibrillation may be limited by heat from intracardiac blood flow. We therefore evaluated the ability to create cryolesions using an argon-based cryoclamp device, which temporarily occludes blood flow and facilitates transmurality., Methods: Six mongrel dogs underwent sternotomy. A clamp employing a 10-cm argon-based linear cryoablation device was used epicardially to isolate the pulmonary veins and left atrial appendage. After clamping of lesions, the probe was removed from the cryoclamp device, and the remaining linear lesions, analogous to the Cox maze III, were performed. Pulmonary vein stenosis was evaluated with the use of magnetic resonance imaging. Left atrial function and pulmonary venous flow velocities were assessed with transesophageal echocardiography. Transmurality was confirmed both electrically and histologically. Animals were then put to death at 30 days., Results: All acute and chronic cryoclamp lesions produced conduction block. There was no change in right (RPV) or left pulmonary vein (LPV) diameter on the basis of magnetic resonance imaging at baseline and at planned death (RPV-1, 19.6 +/- 2.9 mm vs 16.9 +/- 2.8 mm, P = .22; RPV-2, 13.2 +/- 2.0 mm vs 11.8 +/- 1.6 mm, P = .22; and LPV, 12.2 +/- 2.4 mm vs 11.2 +/- 1.9 mm, P = .30). Left atrial function and pulmonary venous flow velocities were unchanged. Tissue sections determined transmurality in 93% of cryoclamp lesions and 84% of linear ablations performed with the 10-cm malleable probe., Conclusions: Epicardial application of this cryoclamp device on the beating heart produced transmural lesions, which persisted 30 days. Linear epicardial cryoablation was not as effective as the cryoclamp device at producing consistent transmural lesions. This novel, versatile device may be useful in treating patients with atrial fibrillation on the beating heart without cardiopulmonary bypass.

Objective: The radial artery has more smooth muscle in its wall than the other arterial conduits and is known to be vasospastic. Because it is frequently necessary to use vasoconstrictors early after coronary bypass surgery we investigated the effects of phenylephrine on conduit flow in this setting., Methods: Thirty patients undergoing coronary artery bypass with all arterial conduits in which the radial artery was used as a T-graft were randomly assigned to receive intravenous infusions of normal saline (n = 10); nitroglycerin, 0.5 microg x kg x min (n = 11); or nicardipine, 0.5 microg x kg x min (n = 9), beginning early in the operation. After discontinuation of cardiopulmonary bypass and achievement of stable hemodynamics, control measurements were obtained, and this was followed by phenylephrine infusion to achieve a 20% increase in mean arterial pressure, after which the measurements were repeated., Results: Mean radial artery flow increased similarly in all groups: normal saline, 40% +/- 25%; nicardipine, 37% +/- 27%; nitroglycerin, 48% +/- 36% (P = .533). Comparable changes occurred in arterial pressure and systemic vascular resistance, whereas the cardiac index remained unchanged., Conclusion: Radial artery blood flow increases when the mean arterial pressure is increased with phenylephrine. There was no evidence of a conduit vasoconstrictive effect, which could limit or reduce conduit flow. Vasoconstriction with phenylephrine is appropriate to provide adequate perfusion pressure for radial artery grafts.

Background: The study evaluated the efficacy of recombinant human antithrombin (rhAT) for restoring heparin responsiveness in heparin resistant patients undergoing cardiac surgery., Methods: This was a multicenter, randomized, double-blind, placebo-controlled study in heparin-resistant patients undergoing cardiac surgery with cardiopulmonary bypass. Heparin resistance was diagnosed when the activated clotting time was less than 480 s after 400 U/kg heparin. Fifty-four heparin-resistant patients were randomized. One cohort received 75 U/kg rhAT, and the other received normal saline. If the activated clotting time remained less than 480 s, this was considered treatment failure, and 2 units fresh frozen plasma was transfused. Patients were monitored for adverse events., Results: Only 19% of patients in the rhAT group received fresh frozen plasma, compared with 81% of patients in the placebo group (P < 0.001). During their hospitalization, 48% of patients in the rhAT group received fresh frozen plasma, compared with 85% of patients in the placebo group (P = 0.009). Patients in the placebo group required higher heparin doses (P < 0.005) for anticoagulation. There was no increase in serious adverse events associated with rhAT. There was increased blood loss 12 h postoperatively (P = 0.05) with a trend toward increased 24-h bleeding in the rhAT group (P = 0.06). There was no difference between the groups in blood and platelet transfusions., Conclusion: Treatment with 75 U/kg rhAT is effective in restoring heparin responsiveness and promoting therapeutic anticoagulation in the majority of heparin-resistant patients. Treating heparin-resistant patients with rhAT may decrease the requirement for heparin and fresh frozen plasma.

Objective: To assess the incidence of myocardial ischemia in patients receiving radial arterial and left internal thoracic arterial conduits (RA+LITA) during the postrevascularization period., Design: Nonrandomized observational sequential cohort., Setting: University hospital., Participants: Thirty adult patients, scheduled for elective coronary artery bypass graft surgery with RA+LITA, compared with 30 patients who received saphenous vein graft and left internal thoracic arterial conduits., Interventions: None., Measurements and Main Results: Myocardial ischemic episodes were defined as reversible ST-segment depressions or elevations >or=1 mm and >or=2 mm at J +60 msec and lasting >or=1 minute using 2-channel Holter monitoring. During the post-cardiopulmonary bypass period, a significantly higher number of patients with >or=2 mm ischemic episodes (21.7%; p = 0.015) and higher number of >or=2 mm ischemic episodes per hour (0.19 +/- 0.4 episodes/hr; p = 0.03) were observed in the radial artery group versus the comparison group (0% of patients and 0 episodes/hr). During the postoperative period (24 hours), a significantly longer duration of >or=2 mm ischemic episodes was observed in the radial artery group (24 +/- 33 minutes v 8.4 +/- 21 minutes; p = 0.046). Radial artery graft, preoperative calcium antagonists, and pulmonary arterial mean pressure were independent predictors of the duration and area under the ST-segment curve of >or=2 mm ischemic episodes during the postoperative period., Conclusion: There is an association between the use of the radial artery graft and the incidence and severity of >or=2 mm postrevascularization ischemic episodes., (Copyright 2001 by W.B. Saunders Company.)

Unlabelled: Atrial fibrillation is a common complication of coronary artery bypass graft (CABG) surgery that is associated with adverse patient outcomes. We evaluated whether preexisting abnormalities of cardiac structure or function detected with transesophageal echocardiography (TEE) are prevalent in patients later developing atrial fibrillation after CABG surgery. TEE imaging was performed after induction of general anesthesia, but before primary CABG surgery, in 62 consecutive patients without cardiac valvular disease or preexisting atrial fibrillation. Measurements included left atrial diameter, left ventricular wall thickness, left ventricular end-systolic and end-diastolic dimensions and fractional area change. Pulsed-wave Doppler measurements of pulmonary venous and trans-mitral blood flow velocity were obtained. Continuous monitoring with telemetry electrocardiography for the development of atrial fibrillation was performed. Eighteen patients (29%) developed postoperative atrial fibrillation. There were no significant differences in left atrial or left ventricular TEE variables or pulsed-wave Doppler pulmonary venous flow measurements between patients with and without postoperative atrial fibrillation. After adjusting for age and duration of aortic cross-clamping, there were no differences in the transmitral Doppler diastolic filling variables between these same groups. These data suggest that atrial fibrillation commonly occurs after CABG surgery in the absence of atrial enlargement or Doppler-derived cardiac functional abnormalities. The data imply that the use of TEE immediately before surgery would be an insensitive means for routine identification of patients susceptible to this arrhythmia., Implications: Transesophageal echocardiography performed immediately before coronary artery bypass graft (CABG) surgery is not useful for prediction of susceptibility to develop atrial fibrillation postoperatively. Postoperative atrial fibrillation commonly occurs after CABG surgery in the absence of preoperative atrial enlargement or Doppler derived functional abnormalities.

Unlabelled: Anticoagulation with recombinant hirudin (r-hirudin) (Refludan) has been suggested as an alternative to heparin for patients with heparin-induced thrombocytopenia requiring cardiac surgery. We sought to develop a modified activated coagulation time (ACT) that would allow quantification of the levels of r-hirudin required during cardiopulmonary bypass (CPB). Twenty-one patients scheduled for elective cardiac surgical procedures requiring CPB were enrolled in this IRB-approved study. R-hirudin was added to blood specimens obtained before heparin administration (before CPB) and 30 min after heparin neutralization with protamine (after CPB) to result in concentrations of 0, 2, 4, 6, 7, or 8 microg/mL. Kaolin/ACT and complete blood count measurements were assayed in native specimens (first 10 patients, Phase I) or in specimens mixed with equal volumes of commercial normal plasma (second 11 patients, Phase II). In Phase I, good (r(2) = 0.83) linear relationships between ACT values and r-hirudin concentrations (< or =4 microg/mL) were observed in specimens obtained before CPB. However, ACT values were markedly prolonged (P < 0.0001) by r-hirudin in specimens obtained after CPB, with ACT values generally exceeding the ACT's detection limit (>999 s) at hirudin concentrations >2 microg/mL. In patient specimens mixed with normal plasma (Phase II), ACT/hirudin relationships (i.e., hirudin/ACT slope values obtained with hirudin concentration < or =4 microg/mL) in the post-CPB period (0.022 +/- 0.004 microg. mL(-1). s(-1)) were similar (P = 0.47) to those (0.019 +/- 0.004 microg. mL(-1). s(-1)) obtained in the pre-CPB period. Accordingly, a significant relationship between normal plasma-supplemented ACT values and predilution hirudin concentration was obtained in the post-CPB (hirudin = 0.039ACT - 4.34, r(2) = 0.91) period. Although our data demonstrate that the ACT test cannot be used to monitor hirudin during CPB, the addition of 50% normal plasma to post-CPB hemodiluted blood specimens yields a consistent linear relationship between hirudin concentration and ACT values up to a predilution concentration of 8 microg/mL. Plasma-modified ACT may be useful in monitoring hirudin anticoagulation during CPB., Implications: A modified activated clotting time test system that may be helpful in monitoring hirudin anticoagulation in patients with heparin-induced thrombocytopenia during cardiac surgery with cardiopulmonary bypass is described.

Study Objectives: To determine whether the application of continuous aspiration of subglottic secretions (CASS) is associated with a decreased incidence of ventilator-associated pneumonia (VAP)., Design: Prospective clinical trial., Setting: Cardiothoracic ICU (CTICU) of Barnes-Jewish Hospital, St. Louis, a university-affiliated teaching hospital., Patients: Three hundred forty-three patients undergoing cardiac surgery and requiring mechanical ventilation in the CTICU., Interventions: Patients were assigned to receive either CASS, using a specially designed endotracheal tube (Hi-Lo Evac; Mallinckrodt Inc; Athlone, Ireland), or routine postoperative medical care without CASS., Results: One hundred sixty patients were assigned to receive CASS, and 183 were assigned to receive routine postoperative medical care without CASS. The two groups were similar at the time of randomization with regard to demographic characteristics, surgical procedures performed, and severity of illness. Risk factors for the development of VAP were also similar during the study period for both treatment groups. VAP was seen in 8 patients (5.0%) receiving CASS and in 15 patients (8. 2%) receiving routine postoperative medical care without CASS (relative risk, 0.61%; 95% confidence interval, 0.27 to 1.40; p = 0. 238). Episodes of VAP occurred statistically later among patients receiving CASS ([mean +/- SD] 5.6 +/- 2.3 days) than among patients who did not receive CASS (2.9 +/- 1.2 days); (p = 0.006). No statistically significant differences for hospital mortality, overall duration of mechanical ventilation, lengths of stay in the hospital or CTICU, or acquired organ system derangements were found between the two treatment groups. No complications related to CASS were observed in the intervention group., Conclusions: Our findings suggest that CASS can be safely administered to patients undergoing cardiac surgery. The occurrence of VAP can be significantly delayed among patients undergoing cardiac surgery using this simple-to-apply technique.

Perioperative myocardial ischemic episodes are predictive of adverse cardiac outcomes after coronary artery bypass surgery. We compared the efficacy of continuous infusions of nicardipine (group NIC) and nitroglycerin (group NTG) in reducing the frequency and severity of myocardial ischemic episodes. Patients received either a nicardipine infusion, 0.7 to 1.4 microg/kg/min (n = 30), nitroglycerin infusion, 0.5 to 1 microg/kg/min (n = 30), or neither medication (group C; n = 17) after aortic occlusion clamp release and for 24 hours postoperatively. Myocardial ischemic episodes were considered as ST segment depressions or elevations of 1 mm or greater from baseline, each at J + 60 milliseconds and lasting 1 minute or greater, using a two-channel Holter monitor. Only nicardipine significantly decreased the duration (3.2 +/- 1.2 min/h) and the area under the ST time curve (AUC; 5.7 +/- 15.7 AUC/h) of 1-mm or greater myocardial ischemic episodes compared with group C (17.2 +/- 5.6 min/h and 30.1 +/- 49 AUC/h, respectively) during the intraoperative postbypass period. A trend toward lower frequency, duration, and area under the ST time curve of myocardial ischemic episodes was observed in group NIC compared with group NTG. Cardiac indices and mixed venous oxygen saturations were significantly greater, whereas systemic pressures were less in group NIC compared with group NTG for the same period. These results suggest that nicardipine, but not nitroglycerin, decreased the duration and area under the ST time curve of myocardial ischemic episodes shortly after coronary revascularization. Larger studies are required to verify the efficacy of nicardipine in reducing the severity of myocardial ischemia during cardiac surgery.

Patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) are at increased risk for excessive perioperative blood loss requiring transfusion of blood products. Point-of-care evaluation of platelets, coagulation factors, and fibrinogen can enable physicians to rapidly assess bleeding abnormalities, facilitate the optimal administration of pharmacological and transfusion-based therapy, and also identify patients with surgical bleeding. The ability to reduce the unnecessary use of blood products in this setting has important implications for emerging issues in blood inventory and blood costs. The ability to decrease surgical time, along with exploration rates, has important consequences for health care costs in an increasingly managed health care environment.

The incidence of left ventricular (LV) diastolic abnormalities in adult cardiac surgical patients has not previously been adequately investigated. The present study was performed to characterize LV diastolic filling patterns by performing transesophageal Doppler echocardiographic (TEE) studies in patients undergoing cardiac surgical procedures and thus indirectly assess diastolic function in these patients. Doppler TEE studies were performed and transmitral flow (TMF) and pulmonary venous flow (PVF) velocities were recorded in 104 patients intraoperatively. Peak early (E) and late (A) TMF velocities and systolic (S) and diastolic (D) forward PVF velocities were assessed and deceleration time (DT) was measured in all patients. For analysis, the study patients were classified into three groups according to the ratio of the TMF E to A velocity curves: group I with E/A ratio less than 1.0, group II with E/A ratio of 1.0 to less than 2.0, and group III with E/A ratio of 2.0 or greater. A filling pattern of abnormal LV relaxation was found in 73 patients (E/A < 1.0), a normal or pseudonormal pattern was present in 27 patients (1.0 < or = E/A < or = 2.0), and restrictive filling in 4 patients (E/A > 2.0). Patients with impaired relaxation had a greater incidence of recent myocardial infarction and congestive heart failure (CHF) than those with normal or pseudonormal filling patterns. Within group II, patients with CHF had higher TMF E deceleration rates and lower PVF S/D ratios compared with those without CHF (P < .05). Doppler echocardiographic examination of TMF and PVF velocities suggests that abnormalities in diastolic function are prevalent in adult cardiac surgical patients.

The aim of this study is to characterize and compare the left ventricular (LV) diastolic filling patterns in patients with paroxysmal (PAF) versus chronic atrial fibrillation (CAF) undergoing the maze procedure and to examine their relation with the hemodynamic status. Fifty patients with PAF and 22 with CAF were studied. Hemodynamic measurements and transesophageal echocardiography (TEE) were performed after the induction of anesthesia but before surgical incision, at stable conditions. Transmitral (TMF) and pulmonary venous flow (PVF) velocities were recorded with the pulsed Doppler method. Statistical analysis between the two groups (PAF and CAF) was performed using Student's t-test and chi-squared test, with P less than .05 statistically significant. Compared with patients in the PAF group, those in the CAF group had: (1) higher pulmonary capillary wedge pressure (14 +/- 5 v 12 +/- 4 mm Hg; P < .05), (2) lower left ventricular fraction of area change (43% +/- 6% v 52% +/- 9%; P < .01), (3) slower PVF systolic wave velocity (23 +/- 10 v 35 +/- 15 cm/s; P < .05), and (4) lower ratio of PVF systolic to diastolic wave velocity (0.75 +/- 0.3 v 1.2 +/- 0.4; P < .05). In the present study, LV filling patterns of abnormal relaxation were found in all our patients who underwent the maze procedure for CAF or PAF. Although the cause of LV filling abnormalities is not apparent, the data suggest LV diastolic dysfunction is prevalent in these patients.