Electroencephalography-Guided Anesthesia and Delirium in Older Adults After Cardiac Surgery: The ENGAGES-Canada Randomized Clinical Trial.

Importance: Intraoperative electroencephalogram (EEG) waveform suppression, suggesting excessive general anesthesia, has been associated with postoperative delirium. Objective: To assess whether EEG-guided anesthesia decreases the incidence of delirium after cardiac surgery. Design, Setting, and Participants: Randomized, parallel-group clinical trial of 1140 adults 60 years or older undergoing cardiac surgery at 4 Canadian hospitals. Recruitment was from December 2016 to February 2022, with follow-up until February 2023. Interventions: Patients were randomized in a 1:1 ratio (stratified by hospital) to receive EEG-guided anesthesia (n = 567) or usual care (n = 573). Patients and those assessing outcomes were blinded to group assignment. Main Outcomes and Measures: The primary outcome was delirium during postoperative days 1 through 5. Intraoperative measures included anesthetic concentration and EEG suppression time. Secondary outcomes included intensive care and hospital length of stay. Serious adverse events included intraoperative awareness, medical complications, and 30-day mortality. Results: Of 1140 randomized patients (median [IQR] age, 70 [65-75] years; 282 [24.7%] women), 1131 (99.2%) were assessed for the primary outcome. Delirium during postoperative days 1 to 5 occurred in 102 of 562 patients (18.15%) in the EEG-guided group and 103 of 569 patients (18.10%) in the usual care group (difference, 0.05% [95% CI, -4.57% to 4.67%]). In the EEG-guided group compared with the usual care group, the median volatile anesthetic minimum alveolar concentration was 0.14 (95% CI, 0.15 to 0.13) lower (0.66 vs 0.80) and there was a 7.7-minute (95% CI, 10.6 to 4.7) decrease in the median total time spent with EEG suppression (4.0 vs 11.7 min). There were no significant differences between groups in median length of intensive care unit (difference, 0 days [95% CI, -0.31 to 0.31]) or hospital stay (difference, 0 days [95% CI, -0.94 to 0.94]). No patients reported intraoperative awareness. Medical complications occurred in 64 of 567 patients (11.3%) in the EEG-guided group and 73 of 573 (12.7%) in the usual care group. Thirty-day mortality occurred in 8 of 567 patients (1.4%) in the EEG-guided group and 13 of 573 (2.3%) in the usual care group. Conclusions and Relevance: Among older adults undergoing cardiac surgery, EEG-guided anesthetic administration to minimize EEG suppression, compared with usual care, did not decrease the incidence of postoperative delirium. This finding does not support EEG-guided anesthesia for this indication. Trial Registration: ClinicalTrials.gov Identifier: NCT02692300.

Transesophageal Echocardiography Guided Partial Right Atrial Inflow Occlusion - A Case Study.

Deployment of stent-grafts and other endovascular devices is a common technique for various vascular repair procedures. Induced, transient, periods of hypotension are essential to the precise deployment of a device as this minimizes displacement that can result from high pressure aortic flow. Partial inflow occlusion of the right atrium is a reliable, precise, and safe method of achieving this. We present a case where intraoperative transesophageal echocardiography (TEE) was used to guide and confirm balloon placement for right atrium inflow occlusion during a thoracic endovascular aneurysm repair (TEVAR) procedure for repair of an aortic dissection in a 67 year old male. This highlights a novel use of TEE in the context of endovascular surgery, and showcases an alternative method of reliably achieving transient hypotension.

Protocol for the electroencephalography guidance of anesthesia to alleviate geriatric syndromes (ENGAGES-Canada) study: A pragmatic, randomized clinical trial.

Background:  There is some evidence that electroencephalography guidance of general anesthesia can decrease postoperative delirium after non-cardiac surgery.  There is limited evidence in this regard for cardiac surgery.  A suppressed electroencephalogram pattern, occurring with deep anesthesia, is associated with increased incidence of postoperative delirium (POD) and death.  However, it is not yet clear whether this electroencephalographic pattern reflects an underlying vulnerability associated with increased incidence of delirium and mortality, or whether it is a modifiable risk factor for these adverse outcomes. Methods:  The Electroe ncephalography Guidance of Anesthesia to Alleviate Geriatric Syndromes ( ENGAGES-Canada) is an ongoing pragmatic 1200 patient trial at four Canadian sites.  The study compares the effect of two anesthetic management approaches on the incidence of POD after cardiac surgery.  One approach is based on current standard anesthetic practice and the other on electroencephalography guidance to reduce POD. In the guided arm, clinicians are encouraged to decrease anesthetic administration, primarily if there is electroencephalogram suppression and secondarily if the EEG index is lower than the manufacturers recommended value (bispectral index (BIS) or WAVcns below 40 or Patient State Index below 25).  The aim in the guided group is to administer the minimum concentration of anesthetic considered safe for individual patients.  The primary outcome of the study is the incidence of POD, detected using the confusion assessment method or the confusion assessment method for the intensive care unit; coupled with structured delirium chart review.  Secondary outcomes include unexpected intraoperative movement, awareness, length of intensive care unit and hospital stay, delirium severity and duration, quality of life, falls, and predictors and outcomes of perioperative distress and dissociation. Discussion:  The ENGAGES-Canada trial will help to clarify whether or not using the electroencephalogram to guide anesthetic administration during cardiac surgery decreases the incidence, severity, and duration of POD. Registration: ClinicalTrials.gov ( NCT02692300) 26/02/2016.

Spinal Anesthesia is Associated with Lower Recurrence Rates after Resection of Nonmuscle Invasive Bladder Cancer.

PURPOSE: We sought to determine whether anesthetic type (general vs spinal) would influence cancer recurrence following transurethral resection of bladder tumors. MATERIALS AND METHODS: With institutional ethics board approval we examined the electronic medical records of all patients who underwent transurethral bladder tumor resection for nonmuscle invasive urothelial bladder cancer between 2011 and 2013 at a single tertiary care center. Followup information was gathered on all patients in December 2016. The time to first cancer recurrence and the incidence of cancer recurrence were the main outcome measures. RESULTS: A total of 231 patients underwent 1 or more transurethral bladder tumor resections between 2011 and 2013. Of the 231 patients 135 received spinal anesthesia and 96 received general anesthesia. On univariable analysis the 135 patients who received spinal anesthesia had a longer median time to recurrence than the 96 who received general anesthesia (42.1 vs 17.2 months, p = 0.014). As anticipated, adjuvant therapies and risk category were associated with recurrence rates (p = 0.003 and 0.042, respectively). On multivariable analyses incorporating a priori variables of nonmuscle invasive bladder cancer risk stratification and postoperative therapies the patients who received general anesthesia had a higher incidence of recurrence (OR 2.06, 95% CI 1.14-3.74, p = 0.017) and an earlier time to recurrence (HR 1.57, 95% CI 1.13-2.19, p = 0.008) than those who received spinal anesthesia. Anesthetic type was not associated with cancer progression or overall mortality. CONCLUSIONS: Patients who received spinal anesthesia had a lower incidence of recurrence and a delayed time to recurrence following transurethral bladder tumor resection for nonmuscle invasive bladder cancer. These findings should prompt large-scale prospective studies to confirm this association.

Unrecognized tamponade diagnosed pre-induction by focused echocardiography.

PURPOSE: We report a case of unrecognized cardiac tamponade diagnosed pre-induction by focused transthoracic echocardiography (TTE). The value of focused perioperative TTE, the anesthetic implications of Churg-Strauss syndrome, and the diagnosis of cardiac tamponade are discussed. CLINICAL FEATURES: A 58-yr-old man with a history of severe asymptomatic aortic stenosis presented for elective endoscopic sinus surgery for intractable nasal polyps with recurrent sinusitis. His cardiologist and cardiac surgeon had recommended proceeding with surgery, as aortic valve replacement was not indicated because he was asymptomatic. Prior to induction, a focused TTE was performed by anesthesia in order to document the degree of aortic stenosis, baseline ventricular function, and baseline volume status. This provided a baseline for comparison in case the patient's hemodynamic status should deteriorate intraoperatively. Unexpectedly, the TTE examination revealed cardiac tamponade. After confirmation of the diagnosis by cardiology, urgent pericardiocentesis was performed. A diagnosis of Churg-Strauss syndrome was ultimately made, and the patient was treated with high-dose prednisone therapy. CONCLUSION: Focused TTE has significant clinical utility for the diagnosis and assessment of hemodynamically significant cardiac conditions, particularly in the complex patient where clinical examination is challenging and echocardiographic findings can have immediate management implications.

How well are prebooked surgical step-down units utilized?

STUDY OBJECTIVE: To evaluate the utilization of the surgical step-down unit (SSDU) by a sample of patients who were preoperatively booked for admission to the unit, and to identify those patient characteristics and perioperative variables that are associated with an intervention in the unit. DESIGN: Retrospective chart review. SETTING: Canadian tertiary-care facility. MEASUREMENTS: Data from 133 elective surgery patients with prebooked SSDU beds were recorded, including comorbidities, Surgical Risk Scale (SRS), Surgical Apgar Score (SAS), and number and nature of interventions and events occurring in the SSDU. MAIN RESULTS: Of the 133 patients scheduled for SSDU admission, 60 (45.1%) were actually admitted and the other 73 (54.9%) were admitted directly to the surgical ward or else discharged. Of the patients admitted to the SSDU, 48.3% had an intervention during their stay. In logistic regression, the SRS was a significant predictor (P < 0.001) of SSDU use, while the SAS was a significant predictor (P = 0.034) of the need for an intervention or the likelihood of an event while in the SSDU. CONCLUSIONS: Less than half of patients identified were actually admitted to the SSDU postoperatively; of those, less than half required an intervention. The Surgical Apgar Score, a score based on intraoperative factors, predicted the need for an intervention during SSDU admission. Consideration should be given to the development of a predictive score that emphasizes intraoperative factors and early postoperative factors to optimize allocation of this scarce resource.

Brief report: Focused transthoracic echocardiography training in a cohort of Canadian anesthesiology residents: a pilot study.

PURPOSE: Bedside transthoracic echocardiography (TTE) is useful for rapid assessment and treatment of hemodynamic disturbances. Transthoracic echocardiography is not standard in Canadian anesthesia training even though undifferentiated hemodynamic disturbances are common in the perioperative setting. The objectives of this pilot study were to determine 1) whether it is feasible to implement a focused bedside TTE curriculum within core anesthesiology training, 2) whether changes could be detected and quantified following the program of study, and 3) whether curriculum implementation might lead to a significant increase in anesthesiology residents' TTE knowledge-base. METHODS: In this single-centre cohort pilot investigation, anesthesiology residents at Queen's University received focused bedside TTE training during the winter of 2011. The curriculum consisted of four three-hour sessions with both didactic and practical components. Pre- and post-curriculum examinations were administered, and examination results were compared using non-parametric tests. The primary outcome was the difference in mean pre- and post-curriculum examination scores. RESULTS: Ten participants completed pre- and post-curriculum examinations. Four residents were unable to participate in the curriculum but served as controls. Mean pretest scores (out of 50) were similar between the two groups (participants 23.9 vs controls 23.5; P = 0.83, Mann-Whitney U). Mean scores improved by 13.0 points following intervention but improved by only 1.3 points for controls, (P = 0.009, Mann-Whitney U). CONCLUSION: This pilot investigation suggests that implementation of a focused bedside TTE curriculum within anesthesia training is feasible, quantifiable, and effective for increasing anesthesia residents' TTE knowledge-base. This pilot study suggests that further investigation is warranted to determine the impact of this perioperative TTE curriculum.

Transesophageal echocardiography of a dislodged left atrial appendage thrombus and its subsequent surgical removal during coronary artery bypass graft surgery.

Left atrial appendage (LAA) thrombus is a common finding in patients with atrial fibrillation and a major source of emboli that cause strokes. The incidental finding of an LAA thrombus during cardiac surgery is an infrequent finding during routine intraoperative echocardiography, and optimal management is not well defined. A case of a large, incidentally discovered LAA thrombus that became mobile on initiation of cardiopulmonary bypass in a patient undergoing coronary artery bypass graft surgery is presented. Intraoperative transesophageal echocardiography diagnosed the thrombus, discovered its dislodgement from the LAA, and very interestingly demonstrated its surgical removal. This case demonstrates the ability of intraoperative transesophageal echocardiography to alter surgical management and provides support for its routine use in cases in which LAA thrombi are likely.