Childhood Maltreatment and Leukocyte Telomere Length: Cardiac Vagal Activity Influences the Relation in Older Adults.

OBJECTIVE: Childhood maltreatment is associated with shorter leukocyte telomere length (LTL). However, the influence of cardiac vagal control on this relation is unknown. We examined whether cardiac vagal control at rest and in response to stress moderates or cross-sectionally mediates the relationship between childhood maltreatment and LTL. METHODS: Participants were 1179 men and women (aged 65 [7.2] years) suffering from coronary artery disease or non-cardiovascular chronic disease. They completed a childhood maltreatment questionnaire and underwent a stress protocol while electrocardiogram was monitored. High-frequency heart rate variability (HF-HRV) measures were obtained at rest, during stress, and after stress in absolute and normalized units (nu). LTL was measured using quantitative polymerase chain reaction. Mediation and moderation analyses were performed. RESULT: HF-HRV and HF-HRV in normalized units (HFnu) measures did not mediate the childhood maltreatment-LTL relation. However, baseline HFnu ( p = .027) and HFnu reactivity ( p = .051) moderated the relation. Specifically, maltreatment was associated with significantly lower LTL among those with baseline HFnu at ( b = -0.059, p = .003) or below the mean ( b = -0.103, p < .001), but not among those with higher baseline HFnu. It was also associated with significantly lower LTL among participants who showed either blunted ( b = -0.058, p = .004) or increased HFnu ( b = -0.099, p = .001) responses to stress but not in those with large decreases in HFnu. CONCLUSIONS: Childhood maltreatment was associated with lower LTL in those who showed a distinct cardiac vagal profile at baseline and in response to stress. The mechanisms and implications remain to be determined.

Bilateral nephrectomy impairs cardiovascular function and cerebral perfusion in a rat model of acute hemodilutional anemia.

Anemia and renal failure are independent risk factors for perioperative stroke, prompting us to assess the combined impact of acute hemodilutional anemia and bilateral nephrectomy (2Nx) on microvascular brain Po2 (PBro2) in a rat model. Changes in PBro2 (phosphorescence quenching) and cardiac output (CO, echocardiography) were measured in different groups of anesthetized Sprague-Dawley rats (1.5% isoflurane, n = 5-8/group) randomized to Sham 2Nx or 2Nx and subsequently exposed to acute hemodilutional anemia (50% estimated blood volume exchange with 6% hydroxyethyl starch) or time-based controls (no hemodilution). Outcomes were assessed by ANOVA with significance assigned at P < 0.05. At baseline, 2Nx rats demonstrated reduced CO (49.9 ± 9.4 vs. 66.3 ± 19.3 mL/min; P = 0.014) and PBro2 (21.1 ± 2.9 vs. 32.4 ± 3.1 mmHg; P < 0.001) relative to Sham 2Nx rats. Following hemodilution, 2Nx rats demonstrated a further decrease in PBro2 (15.0 ± 6.3 mmHg, P = 0.022). Hemodiluted 2Nx rats did not demonstrate a comparable increase in CO after hemodilution compared with Sham 2Nx (74.8 ± 22.4 vs. 108.9 ± 18.8 mL/min, P = 0.003) that likely contributed to the observed reduction in PBro2. This impaired CO response was associated with reduced fractional shortening (33 ± 9 vs. 51 ± 5%) and increased left ventricular end-systolic volume (156 ± 51 vs. 72 ± 15 µL, P < 0.001) suggestive of systolic dysfunction. By contrast, hemodiluted Sham 2Nx animals demonstrated a robust increase in CO and preserved PBro2. These data support the hypothesis that the kidney plays a central role in maintaining cerebral perfusion and initiating the adaptive increase in CO required to optimize PBro2 during acute anemia.NEW & NOTEWORTHY This study has demonstrated that bilateral nephrectomy acutely impaired cardiac output (CO) and microvascular brain Po2 (PBro2), at baseline. Following acute hemodilution, nephrectomy prevented the adaptive increase in CO associated with acute hemodilution leading to a further reduction in PBro2, accentuating the degree of cerebral tissue hypoxia. These data support a role for the kidney in maintaining PBro2 and initiating the increase in CO that optimized brain perfusion during acute anemia.

Benzodiazepine-Free Cardiac Anesthesia for Reduction of Postoperative Delirium (B-Free): A Protocol for a Multi-centre Randomized Cluster Crossover Trial.

Delirium is common after cardiac surgery and is associated with adverse outcomes. Administration of benzodiazepines before and after cardiac surgery is associated with delirium; guidelines recommend minimizing their use. Benzodiazepine administration during cardiac surgery remains common because of its recognized benefits. The Benzodiazepine-Free Cardiac Anesthesia for Reduction of Postoperative Delirium (B-Free) trial is a randomized cluster crossover trial evaluating whether an institutional policy of restricting intraoperative benzodiazepine administration (ie, ≥ 90% of patients do not receive benzodiazepines during cardiac surgery), as compared with a policy of liberal intraoperative benzodiazepine administration (ie, ≥ 90% of patients receive ≥ 0.03 mg/kg midazolam equivalent), reduces delirium. Hospitals performing ≥ 250 cardiac surgeries a year are included if their cardiac anesthesia group agrees to apply both benzodiazepine policies per their randomization, and patients are assessed for postoperative delirium every 12 hours in routine clinical care. Hospitals apply the restricted or liberal benzodiazepine policy during 12 to 18 crossover periods of 4 weeks each. Randomization for all periods takes place in advance of site startup; sites are notified of their allocated policy during the last week of each crossover period. Policies are applied to all patients undergoing cardiac surgery during the trial period. The primary outcome is the incidence of delirium at up to 72 hours after surgery. The B-Free trial will enroll ≥ 18,000 patients undergoing cardiac surgery at 20 hospitals across North America. Delirium is common after cardiac surgery, and benzodiazepines are associated with the occurrence of delirium. The B-Free trial will determine whether an institutional policy restricting the administration of benzodiazepines during cardiac surgery reduces the incidence of delirium after cardiac surgery. Clinicaltrials.gov registration number: NCT03928236 (First registered April 26, 2019).

L'état confusionnel est fréquent après une chirurgie cardiaque et il est associé à des complications. L'administration de benzodiazépines avant et après une chirurgie cardiaque est associée à l'état confusionnel; dans les lignes directrices, on recommande de réduire leur utilisation au minimum. L'administration de benzodiazépines pendant une chirurgie cardiaque demeure fréquente, en raison des leurs bienfaits reconnus. L'essai B-Free (Benzodiazepine-Free Cardiac Anesthesia for Reduction of Postoperative Delirium ou l'anesthésie sans benzodiazépine en contexte de chirurgie cardiaque pour la réduction de l'état confusionnel postopératoire) est un essai à répartition aléatoire par grappes et avec permutation, visant à évaluer si une politique institutionnelle de restriction de l'administration peropératoire de benzodiazépines (c.-à-d. que ≥ 90 % des patients ne reçoivent pas de benzodiazépines durant une chirurgie cardiaque) réduit l'état confusionnel, comparativement à une politique d'administration peropératoire libérale de benzodiazépines (c.-à-d. que ≥ 90 % des patients reçoivent ≥ 0,03 mg/kg d'équivalent du midazolam). Des hôpitaux effectuant au moins 250 chirurgies cardiaques par année sont inclus dans l'essai si leurs équipes d'anesthésie cardiaque acceptent d'appliquer les deux politiques relatives aux benzodiazépines en vertu de la répartition aléatoire et si les patients sont évalués toutes les 12 heures, en ce qui a trait à l'état confusionnel postopératoire, dans le cadre des soins cliniques habituels. Les hôpitaux mettent en œuvre la politique d'administration restreinte ou libérale de benzodiazépines durant 12 à 18 périodes de permutation de 4 semaines chacune. La répartition aléatoire de l'ensemble des périodes a lieu avant le début de l'essai à l'hôpital; les établissements sont avisés de la politique qui leur est attribuée au cours de la dernière semaine de chaque période de permutation. Les politiques sont appliquées à tous les patients qui subissent une chirurgie cardiaque durant la période de l'essai. Le critère d'évaluation principal est l'incidence de l'état confusionnel dans les 72 heures suivant l'intervention chirurgicale. L'étude B-Free inclura au moins 18 000 patients qui subiront une chirurgie cardiaque dans 20 hôpitaux en l'Amérique du Nord. L'état confusionnel est fréquent après une chirurgie cardiaque, et les benzodiazépines sont associées à la survenue de l'état confusionnel. L'essai B-Free permettra de déterminer si une politique institutionnelle de restriction de l'administration de benzodiazépines durant une chirurgie cardiaque réduit l'incidence de l'état confusionnel après une telle chirurgie.Clinicaltrials.gov registration number: NCT03928236 (First registered April 26, 2019).

Perioperative Doppler ultrasound assessment of portal vein flow pulsatility in high-risk cardiac surgery patients: a multicentre prospective cohort study.

BACKGROUND: Portal vein Doppler ultrasound pulsatility measured by transoesophageal echocardiography is a marker of the haemodynamic impact of venous congestion in cardiac surgery. We investigated whether the presence of abnormal portal vein flow pulsatility is associated with a longer duration of invasive life support and postoperative complications in high-risk patients. METHODS: In this multicentre cohort study, pulsed-wave Doppler ultrasound assessments of portal vein flow were performed during anaesthesia before initiation of cardiopulmonary bypass (before CPB) and after separation of cardiopulmonary bypass (after CPB). Abnormal pulsatility was defined as portal pulsatility fraction (PPF) ≥50% (PPF50). The primary outcome was the cumulative time in perioperative organ dysfunction (TPOD) requiring invasive life support during 28 days. Secondary outcomes included major postoperative complications. RESULTS: 373 patients, 71 (22.0%) had PPF50 before CPB and 77 (24.9%) after CPB. PPF50 was associated with longer duration of TPOD (median [inter-quartile range]; before CPB: 27 h [11-72] vs 19 h [8.5-42], P=0.02; after CPB: 27 h [11-61] vs 20 h [8-42], P=0.006). After adjusting for confounders, PPF50 before CPB showed significant association with TPOD. PPF50 after CPB was associated with a higher rate of major postoperative complications (36.4% vs 20.3%, P=0.006). CONCLUSIONS: Abnormal portal vein flow pulsatility before cardiopulmonary bypass was associated with longer duration of life support therapy after cardiac surgery in high-risk patients. Abnormal portal vein flow pulsatility after cardiopulmonary bypass separation was associated with a higher risk of major postoperative complications although this association was not independent of other factors. CLINICAL TRIAL REGISTRATION: NCT03656263.

Early Detection and Correction of Cerebral Desaturation With Noninvasive Oxy-Hemoglobin, Deoxy-Hemoglobin, and Total Hemoglobin in Cardiac Surgery: A Case Series.

Regional cerebral oxygen saturation (rS o2 ) obtained from near-infrared spectroscopy (NIRS) provides valuable information during cardiac surgery. The rS o2 is calculated from the proportion of oxygenated to total hemoglobin in the cerebral vasculature. Root O3 cerebral oximetry (Masimo) allows for individual identification of changes in total (ΔcHbi), oxygenated (Δ o2 Hbi), and deoxygenated (ΔHHbi) hemoglobin spectral absorptions. Variations in these parameters from baseline help identify the underlying mechanisms of cerebral desaturation. This case series represents the first preliminary description of Δ o2 Hbi, ΔHHbi, and ΔcHbi variations in 10 cardiac surgical settings. Hemoglobin spectral absorption changes can be classified according to 3 distinct variations of cerebral desaturation. Reduced cerebral oxygen content or increased cerebral metabolism without major blood flow changes is reflected by decreased Δ o2 Hbi, unchanged ΔcHbi, and increased ΔHHbi Reduced cerebral arterial blood flow is suggested by decreased Δ o2 Hbi and ΔcHbi, with variable ΔHHbi. Finally, acute cerebral congestion may be suspected with increased ΔHHbi and ΔcHbi with unchanged Δ o2 Hbi. Cerebral desaturation can also result from mixed mechanisms reflected by variable combination of those 3 patterns. Normal cerebral saturation can occur, where reduced cerebral oxygen content such as anemia is balanced by a reduction in cerebral oxygen consumption such as during hypothermia. A summative algorithm using rS o2 , Δ o2 Hbi, ΔHHbi, and ΔcHbi is proposed. Further explorations involving more patients should be performed to establish the potential role and limitations of monitoring hemoglobin spectral absorption signals.

Impact of Processed Electroencephalography in Cardiac Surgery: A Retrospective Analysis.

OBJECTIVE: The use of brain function monitoring with processed electroencephalography (pEEG) during cardiac surgery is gaining interest for the optimization of hypnotic agent delivery during the maintenance of anesthesia. The authors sought to determine whether the routine use of pEEG-guided anesthesia is associated with a reduction of hemodynamic instability during cardiopulmonary bypass (CPB) separation and subsequently reduces vasoactive and inotropic requirements in the intensive care unit. DESIGN: This is a retrospective cohort study based on an existing database. SETTING: A single cardiac surgical center. PARTICIPANTS: Three hundred patients undergoing cardiac surgery, under CPB, between December 2013 and March 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One hundred and fifty patients had pEEG-guided anesthesia, and 150 patients did not have a pEEG-guided anesthesia. Multiple logistic regression demonstrated that pEEG-guided anesthesia was not associated with a successful CPB separation (p = 0.12). However, the use of pEEG-guided anesthesia reduced by 57% the odds of being in a higher category for vasoactive inotropic score compared to patients without pEEG (odds ratio = 0.43; 95% confidence interval: 0.26-0.73; p = 0.002). Duration of mechanical ventilation, fluid balance, and blood losses were also reduced in the pEEG anesthesia-guided group (p < 0.003), but there were no differences in organ dysfunction duration and mortality. CONCLUSION: During cardiac surgery, pEEG-guided anesthesia allowed a reduction in the use of inotropic or vasoactive agents at arrival in the intensive care unit. However, it did not facilitate weaning from CPB compared to a group where pEEG was unavailable. A pEEG-guided anesthetic management could promote early vasopressor weaning after cardiac surgery.

Postoperative outcomes in surgical COVID-19 patients: a multicenter cohort study.

BACKGROUND: Data on postoperative outcomes of the COVID-19 patient population is limited. We described COVID-19 patients who underwent a surgery and the pandemic impact on surgical activities. METHODS: We conducted a multicenter cohort study between March 13 and June 192,020. We included all COVID-19 patients who underwent surgery in nine centres of the Province of Québec, the Canadian province most afflicted by the pandemic. We also included concomitant suspected COVID-19 (subsequently confirmed not to have COVID-19) patients and patients who had recovered from it. We collected data on baseline characteristics, postoperative complications and postoperative mortality. Our primary outcome was 30-day mortality. We also collected data on overall surgical activities during this first wave and during the same period in 2019. RESULTS: We included 44 COVID-19 patients, 18 suspected patients, and 18 patients who had recovered from COVID-19 at time of surgery. Among the 44 COVID-19 patients, 31 surgeries (71%) were urgent and 16 (36%) were major. In these patients, pulmonary complications were frequent (25%) and 30-day mortality was high (15.9%). This mortality was higher in patients with symptoms (23.1%) compared to those without symptoms (5.6%), although not statistically significant (p = 0.118). Of the total 22,616 cases performed among participating centres during the study period, only 0.19% had COVID-19 at the time of surgery. Fewer procedures were performed during the study period compared to the same period in 2019 (44,486 cases). CONCLUSION: In this Canadian cohort study, postoperative 30-day mortality in COVID-19 patients undergoing surgery was high (15.9%). Although few surgeries were performed on COVID-19 patients, the pandemic impact on surgical activity volume was important. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04458337 .

Should we use diastolic function parameters to determine preload responsiveness in cardiac surgery? A pilot study.

BACKGROUND: Left ventricular (LV) diastolic function (DF) may play an important role in predicting fluid responsiveness. However, few studies assessed the role of diastolic function in predicting fluid responsiveness. The aim of this pilot study was to assess whether parameters of right and left diastolic function assessed with transesophageal echocardiography, including the mitral E/e' ratio, is associated with fluid responsiveness among patients undergoing elective bypass graft surgery. We also sought to compare other methods of fluid responsiveness assessment, including echocardiographic and hemodynamic parameters, pulse pressure variation, and stroke volume variation (SVV) (arterial pulse contour analysis, Flotrac/Vigileo system). RESULTS: We prospectively studied seventy patients undergoing coronary artery bypass grafting (CABG) monitored with a radial arterial catheter, transesophageal echocardiography (TEE), and a pulmonary artery catheter (for cardiac output measurements), before and after the administration of 500 mL of crystalloid over 10 min after the anesthetic induction. Thirteen patients were excluded (total of 57 patients). Fluid responsiveness was defined as an increase in cardiac index of ≥ 15%. There were 21 responders (36.8%) and 36 non-responders (63.2%). No difference in baseline pulsed wave Doppler echocardiographic measurements of any components of the mitral, tricuspid, and pulmonary and hepatic venous flows were found between responders and non-responders. There was no difference in MV tissue Doppler measurements between responders and non-responders, including E/e' ratio (8.7 ± 4.1 vs. 8.5 ± 2.8 in responders vs. non-responders, P = 0.85). SVV was the only independent variable to predict an increase in cardiac index by multivariate analysis (P = 0.0208, OR = 1.196, 95% CI (1.028-1.393)). CONCLUSIONS: In this pilot study, we found that no parameters of right and left ventricular diastolic function were associated with fluid responsiveness in patients undergoing CABG. SVV was the most useful parameter to predict fluid responsiveness. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02714244 . Registered 21 March 2016-retrospectively registered.

In Vivo Protamine Titration Using Activated Coagulation Time to Neutralize Heparin Anticoagulation in Cardiac Surgery: Proof of Concept.

OBJECTIVE: In vivo protamine titration (IVPT) is based on the observation of a plateau on the decay curve of the celite activated clotting times (ACTs) during protamine infusion for heparin reversal. The aim of the present study was to determine the optimal protamine/heparin ratio to reverse anticoagulation using IVPT curves. DESIGN: Prospective, randomized study. SETTING: Tertiary care university hospital. PARTICIPANTS: The study comprised 138 patients undergoing elective cardiac surgery requiring cardiopulmonary bypass. INTERVENTIONS: The control group was given a protamine infusion of 1.3 mg per 1 mg (100 U) of heparin over 21 minutes. ACT was measured every 3 minutes. In the test group, the protamine dose was prepared using the same ratio as for the control group, and ACT values were measured every 3 minutes until a plateau was reached (2 consecutive ACT values <160 s), at which time the protamine infusion was stopped. The protamine/heparin ratio, blood losses, transfusions, and heparin concentrations were recorded. RESULTS: The protamine dose was lower in the test group (456.00 ± 105.66 mg [control group] v 295.25 ± 100.60 mg [test group]; p < 0.0001). The mean protamine/heparin ratios were 1.30 ± 0.10 (control group) and 0.81 ± 0.22 (test group) (p < 0.0001). Heparin concentrations were greater in the test group 15 minutes (0.10 [0-0.2] U/mL v 0 [0-0.1] U/mL; p = < 0.0001) and 3 hours (0 [0-0.1] U/mL v 0 [0-0] U/mL; p = 0.0002) after protamine infusion. There was no difference in the blood losses and transfusion requirements. CONCLUSIONS: IVPT is safe and efficient in this low-risk population.

A Practical Approach to Cerebro-Somatic Near-Infrared Spectroscopy and Whole-Body Ultrasound.

Near-infrared spectroscopy (NIRS) is an emerging noninvasive monitoring modality based on chromophore absorption of infrared light. Because NIRS provides instantaneous information on cerebral and somatic tissue oxygenation, it becomes mandatory to identify rapidly the etiology of impaired regional oxygenation and thus perfusion. To do so, the use of whole-body ultrasound (WHOBUS) represents a significant advance in the management of patients experiencing cerebral or somatic desaturation. This narrative review describes the authors' experience since 2002 in the use of combined NIRS and WHOBUS. A practical approach in the use of both modalities and their respective limitations is described.

Patient management algorithm combining processed electroencephalographic monitoring with cerebral and somatic near-infrared spectroscopy: a case series.

PURPOSE: Cerebral oximetry is a monitoring tool used in the perioperative care of cardiac surgery patients to ensure adequate cerebral perfusion and oxygenation. When combined with somatic oximetry, the differential diagnosis of cerebral desaturation can be better identified and managed more specifically, as somatic oximetry serves as a global or localized perfusion monitor (depending on its regional position). The use of processed electroencephalography (pEEG) in cardiac surgery could further guide the management of desaturation episodes, as reductions in pEEG activity without a change in the anesthetic agent level indicate potential cerebral ischemia. Continuous integration of multiple monitoring modalities are thus desirable to assess organ perfusion and organ function. CLINICAL FEATURES: Four clinical cases are presented in which the combination of pEEG and cerebro-somatic oximetry assisted with understanding the mechanism of cerebral desaturation encountered during cardiac surgery. CONCLUSION: Integrating combinations of different monitoring modalities such as cerebral and somatic oximetry with pEEG can help the diagnosis and treatment of organ malperfusion and related dysfunction.

RéSUMé: OBJECTIF: L'oxymétrie cérébrale est un outil de monitorage utilisé dans les soins périopératoires des patients de chirurgie cardiaque pour s'assurer que leur cerveau est adéquatement perfusé et oxygéné. Quand on la combine à l'oxymétrie somatique, le diagnostic différentiel de désaturation cérébrale peut être mieux identifié et géré de manière plus spécifique, car l'oxymétrie somatique permet un suivi de la perfusion globale ou localisée (selon l'emplacement du capteur). L'utilisation de l'électroencéphalographie traitée (pEEG) en chirurgie cardiaque pourrait entraîner une meilleure gestion des épisodes de désaturation dans la mesure ou une baisse de l'activité pEEG sans modification du niveau de l'agent anesthésique indique une ischémie cérébrale potentielle. L'intégration continue de multiples modalités de monitorage est donc souhaitable pour évaluer la perfusion et le fonctionnement des organes. CARACTéRISTIQUES CLINIQUES: Quatre cas cliniques sont présentés dans lesquels la combinaison de la pEEG et de l'oxymétrie cérébro-somatique a aidé à comprendre le mécanisme de désaturation cérébrale rencontrée au cours de la chirurgie cardiaque. CONCLUSION: Les combinaisons intégrant différentes modalités de monitorage, telles que l'oxymétrie cérébrale et somatique avec la pEEG, peuvent contribuer au diagnostic et au traitement des troubles de la perfusion des organes et des dysfonctionnements qui en découlent.

Myocardial Protection in Minimally Invasive Mitral Valve Surgery: Retrograde Cardioplegia Alone Using Endovascular Coronary Sinus Catheter Compared With Combined Antegrade and Retrograde Cardioplegia.

OBJECTIVE: To compare myocardial protection with retrograde cardioplegia alone with antegrade and retrograde cardioplegia in minimally invasive mitral valve surgery (MIMS). DESIGN: Retrospective study. SETTING: Tertiary care university hospital. PARTICIPANTS: The authors studied 97 MIMS patients using retrograde cardioplegia alone and 118 MIMS patients using antegrade and retrograde cardioplegia. INTERVENTIONS: The data from patients admitted for MIMS using retrograde cardioplegia (MIMS retro) between 2009 to 2012 were compared with the data from patients undergoing MIMS with antegrade and retrograde cardioplegia (MIMS ante-retro) between 2006 and 2010 (control group). Cardioplegia in the MIMS retro group was delivered solely through an endovascular coronary sinus (CS) catheter positioned under echographic and fluoroscopic guidance. Antegrade and retrograde cardioplegia was used in the MIMS ante-retro group. Data regarding myocardial infarction (MI; creatine kinase Mb, troponin T, electrocardiogram), myocardial function, and hemodynamic stability were collected for comparison. MEASUREMENTS AND MAIN RESULTS: Adequate cardioplegia administration (CS pressure >30 mmHg and asystole) was attained in 74.2% of the patients with retrograde cardioplegia alone. In 23.7% of the patients, the addition of an antegrade cardioplegia was necessary. No difference was observed in the incidence of MI (0 MIMS retro v 1 for MIMS ante-retro, p = 0.3623), difficult separation from cardiopulmonary bypass, and postoperative malignant arrhythmia. No difference was found for maximal creatine kinase Mb (39.1 [28.0-49.1] v 37.9 [28.6-50.9]; p = 0.8299) and for maximal troponin T levels (0.39 [0.27-0.70] v 0.47 [0.32-0.79]; p = 0.1231) for MIMS retro and MIMS ante-retro, respectively. However, lactate levels in the MIMS retro group were significantly lower than in the MIMS ante-retro group (2.1 [1.4-3.05] v 2.4 [1.8-3.3], respectively; p = 0.0453). No difference was observed in duration of intensive care unit stay and death. MIMS retro patients had a shorter hospital stay (7.0 [6.0-8.0] v 8.0 [7.0-9.0] days; p = 0.0003). CONCLUSION: Retrograde cardioplegia administration alone provided comparable myocardial protection to antegrade and retrograde cardioplegia during MIMS, but was not sufficient to achieve asystole in one-fifth of patients.

Acute Right Ventricular Failure in Cardiac Surgery During Cardiopulmonary Bypass Separation: A Retrospective Case Series of 12 Years' Experience With Intratracheal Milrinone Administration.

OBJECTIVE: To report the authors' 12 years of experience with intratracheal milrinone administration and to assess the efficacy and limitations of intratracheal milrinone bolus administration for the treatment of unexpected acute right ventricular (RV) failure in patients undergoing cardiac surgery. DESIGN: Retrospective analysis. SETTING: Single-center university hospital. PARTICIPANTS: One hundred seventy-six patients (4.6%) undergoing on-pump cardiac surgery. INTERVENTIONS: Endotracheal tube administration of milrinone (5-mg bolus) after unexpected acute RV failure during separation from cardiopulmonary bypass (CPB) weaning. RV failure was defined as the simultaneous presence of all of the following criteria: (1) hemodynamic instability or difficult separation from CPB with associated elevated central venous pressure or abnormal RV pressure waveform, (2) >20% reduction of RV fractional area change from baseline evaluated by transesophageal echocardiography, and (3) anatomical visualization of impaired or absent RV wall motion by direct intraoperative visual inspection. MEASUREMENTS AND MAIN RESULTS: Intratracheal milrinone administration was found to improve RV failure in 109 patients (61.9%) whereas RV failure persisted in 67 patients (38.1%). Using a multiple logistic regression model, severely decreased left ventricular ejection fraction (<35% v >50%) (adjusted odds ratio [OR] 3.72; 95% confidence interval [CI] 1.2-11.3; p = 0.012), longer CPB time (adjusted OR 1.014; CI 1.01-1.02; p = 0.001) and elevated postoperative fluid balance (adjusted OR 1.39; CI 1.1-1.8; p = 0.02) were found to be significant predictors of persistent RV failure. CONCLUSION: Intratracheal instillation of milrinone was associated with clinical improvement of RV failure occurring during separation from CPB in almost two-thirds of patients. Factors limiting its therapeutic efficacy include severe left ventricular dysfunction, increased fluid balance, and long CPB time.

Parasympathetic Response Patterns are Associated with Metabolic Syndrome Among Older Women but Not Men.

BACKGROUND: Little is known about the role of physiological stress responses in metabolic syndrome (MetS). PURPOSE: To examine whether patterns of autonomic response to psychological stress are associated with MetS and whether this association is moderated by sex. METHODS: 1121 men and women (Mage = 65.3 ± 6.77 years) with and without coronary artery disease (CAD) underwent an anger recall stressor task. Heart rate and heart-rate variability (HRV; HF, LF/HF) were assessed. Clusters of participants showing similar patterns of response across baseline, stress, and recovery periods were created using ACECLUS and FASTCLUS in SAS. Logistic regressions included clusters and interaction between clusters and sex as independent variables, controlling for relevant covariates. ANCOVAs were conducted in secondary analyses utilizing a continuous composite representation of MetS. RESULTS: Men and women showing greater tonic and phasic HR elevations were more likely to meet MetS criteria (OR = 1.45, [95% CI = 1.02-2.07], p = .037). HF-HRV cluster interacted significantly with sex (p < .001) to predict MetS. In women, those with significant parasympathetic withdrawal to stress and poor recovery were more likely to have MetS than women with a more moderate response (OR = 2.56, [95% CI = 1.23-5.41], p = .013). Women who displayed stress-related parasympathetic activation were also at greater risk of MetS (OR = 2.30, [95% CI = 1.30-4.07], p = .004). Results using a continuous measure of MetS were generally consistent with these findings. CONCLUSION: Among older participants with CAD or other noncardiovascular disease, hyperreactivity to stress was associated with greater prevalence of MetS, particularly in women. Consistent with emerging literature, women who showed blunting or activation of parasympathetic responses to stress were similarly at greater risk.

Perioperative Right Ventricular Pressure Monitoring in Cardiac Surgery.

Right ventricular (RV) dysfunction is a cause of increased morbidity and mortality in both cardiac surgery and noncardiac surgery and in the intensive care unit. Early diagnosis of this condition still poses a challenge. The diagnosis of RV dysfunction traditionally is based on a combination of echocardiography, hemodynamic measurements, and clinical symptoms. This review describes the method of using RV pressure waveform analysis to diagnose and grade the severity of RV dysfunction. The authors describe the technique, optimal use, and pitfalls of this method, which has been used at the Montreal Heart Institute since 2002, and review the current literature on this method. The RV pressure waveform is obtained using a pulmonary artery catheter with the capability of measuring RV pressure by connecting a pressure transducer to the pacemaker port. The authors describe how RV pressure waveform analysis can facilitate the diagnosis of systolic and diastolic RV dysfunction, the evaluation of RV-arterial coupling, and help diagnose RV outflow tract obstruction. RV pressure waveform analysis also can be used to guide pharmacologic treatment and fluid resuscitation strategies for RV dysfunction.

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.

Targeted Temperature Management After Cardiac Arrest: The Montreal Heart Institute Experience.

BACKGROUND: Targeted temperature management (TTM) has been associated with an improvement in neurological function and survival in patients with cardiac arrest (CA) and an initially shockable rhythm. We report the Montreal Heart Institute (MHI) experience using TTM to evaluate mortality and neurological outcome in patients remaining in coma after CA, regardless of the initial rhythm. METHODS: We performed a retrospective review of all patients receiving TTM at the MHI between 2008 and 2015. Primary outcome was a composite of mortality and poor neurological outcome at hospital discharge. We also evaluated the long-term outcomes of those who initially survived to hospital discharge. RESULTS: A total of 147 patients (120 men, mean age 59.5 ± 12.5 years) underwent TTM at the MHI during the study period. Overall survival to hospital discharge with good neurological outcome was 45.6%. Shockable rhythm was associated with a better outcome (mortality odds ratio, 0.212; 95% confidence interval, 0.068-0.664; P = 0.008). Of the 11 initial survivors with a poor neurological status (Cerebral Performance Category ≥ 3), 4 died rapidly (within 1 month of hospital discharge), but 6 (54.5%) markedly improved their neurological status to Cerebral Performance Category 1. Long-term survival (mean follow-up of 38 ± 26 months) for those alive at hospital discharge (n = 76 patients) was 81.9%. CONCLUSION: Our retrospective analysis of CA survivors treated with TTM at MHI showed good survival, similar to the published results from the landmark randomized controlled trials, despite enrolling patients with nonshockable rhythms. A significant proportion of survivors with poor neurological outcome at discharge improved at follow-up.

CONTEXTE: Le contrôle ciblé de la température (CCT) a été associé à une amélioration de la fonction neurologique et de la survie chez les patients en arrêt cardiaque ayant un rythme initialement choquable. Nous présentons l'expérience d'utilisation du CCT à l'Institut de Cardiologie de Montréal (ICM) pour évaluer la mortalité et l'issue neurologique chez les patients qui demeurent comateux après un arrêt cardiaque, indépendamment du rythme initial. MÉTHODOLOGIE: Nous avons effectué une analyse rétrospective de tous les patients ayant fait l'objet d'un CCT à l'ICM entre 2008 et 2015. Le paramètre d'évaluation principal se composait de la mortalité et d'une évolution neurologique défavorable à la sortie de l'hôpital. Nous avons aussi évalué le devenir à long terme des patients ayant initialement survécu après leur congé. RÉSULTATS: Au total, 147 patients (120 hommes, âge moyen de 59,5 ± 12,5 ans) ont fait l'objet d'un CCT à l'ICM pendant la période d'étude. Le taux de survie globale jusqu'à la sortie de l'hôpital avec évolution neurologique favorable a été de 45,6 %. Un rythme choquable a été associé à une meilleure issue (rapport de cotes pour la mortalité = 0,212; intervalle de confiance à 95 % : de 0,068 à 0,664; p = 0,008). Chez les 11 survivants initiaux dont l'état neurologique était altéré (score CPC [Cerebral Performance Category] ≥ 3), 4 sont décédés peu après (dans le mois suivant leur congé), mais 6 (54,5 %) ont vu leur état neurologique s'améliorer considérablement jusqu'à un score CPC de 1. La survie à long terme (durée moyenne du suivi de 38 ± 26 mois) pour les patients vivants à leur sortie de l'hôpital (n = 76 patients) a été de 81,9 %. CONCLUSIONS: Notre analyse rétrospective des survivants d'un arrêt cardiaque traités par CCT à l'ICM a montré une bonne survie, comparable aux résultats publiés d'essais contrôlés phares à répartition aléatoire, malgré l'inscription de patients ayant des rythmes non choquables. Au moment du suivi, une amélioration a été observée chez une forte proportion des survivants dont l'état neurologique était altéré à leur sortie de l'hôpital.

Risk Factors for Radial-to-Femoral Artery Pressure Gradient in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass.

OBJECTIVE: To identify risk factors associated with radial-to-femoral pressure gradient during cardiac surgery with cardiopulmonary bypass (CPB). DESIGN: This is a retrospective, observational study. SETTING: Single specialized cardiothoracic hospital in Montreal, Canada. PARTICIPANTS: Consecutive patients that underwent heart surgery with CPB between 2005 and 2015 (n = 435). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A radial-to-femoral pressure gradient occurred in 146 patients of the 435 patients (34%). Based on the 10,000 bootstrap samples, simple logistic regression models identified the 17 most commonly significant variables across the bootstrap runs. Using these variables, a backward multiple logistic model was performed on the original sample and identified the following independent variables: body surface area (m2) (odds ratio [OR] 0.08, 95% confidence interval [CI] 0.030-0.232), clamping time (minutes) (OR 1.01, 95% CI 1.007-1.018), fluid balance (for 1 liter) (OR 0.81, 95% CI 0.669-0.976), and preoperative hypertension (OR 1.801, 95% CI 1.131-2.868). CONCLUSION: A radial-to-femoral pressure gradient occurs in 34% of patients during cardiac surgery. Patients at risk seem to be of smaller stature, hypertensive, and undergo longer and more complex surgeries.