Elastic recoil signal on tissue doppler imaging of mitral annulus as a qualitative test to identify left ventricular diastolic function.

Introduction: Left ventricular (LV) diastolic dysfunction is common on preoperative screening among patients undergoing surgery. There is no simple screening test at present to suspect LV diastolic dysfunction. This study was aimed to test the hypothesis, whether elastic recoil signal (ERS) on tissue Doppler imaging of mitral annulus (MA TDI) can be used as a qualitative test to differentiate patients from normal LV diastolic function versus patients with LV diastolic dysfunction. Methods: This was a prospective cross-sectional observational study of patients admitted for elective surgeries. Normal diastolic function and categorization of LV diastolic dysfunction into severity grades I, II, or III were performed as per the American Society of Echocardiography/ European Associationof Cardio Vascular Imaging (ASE/EACVI) recommendations for LV diastolic dysfunction. Results: There were 41 (61%) patients with normal LV diastolic function and 26 (39%) patients with various grades of LV diastolic dysfunction. In 38 out of 41 patients with normal LV diastolic function, the characteristic ERS was identified. The ERS was absent in all the patients with any grade of LV diastolic dysfunction. Consistency of identification of ERS on echocardiography was tested with a good interobserver variability coefficient of 0.94 (P-value <0.001). The presence of ERS demonstrated an excellent differentiation to rule out any LV diastolic dysfunction with an area under the receiver operating characteristics curve (AUROC) of 0.96 (CI 0.88-0.99; P value <0.001). Conclusions: To conclude, in a mixed surgical population, the anesthetist could successfully assess LV diastolic dysfunction in the preoperative period and the characteristic ERS on MA TDI signal can be used as a qualitative test to differentiate patients from normal LV diastolic function versus patients with LV diastolic dysfunction using the transthoracic echocardiography (TTE).

Does the endotracheal tube cuff pressure increases with transesophageal probe insertion?

Context: The cuff pressure (CP) of the endotracheal tube (ETT) exceeding 30 cm of H2O results in reduced perfusion of lateral mucosa of trachea leading to complications. As the posterior tracheal wall is in contact with the esophagus, there is a possibility that the insertion of transesophageal echo (TEE) probe may compress the tracheal wall and increase CP. Aims: This study was aimed to assess the impact of TEE probe insertion on CP in adults undergoing cardiac surgery. Settings and Design: Prospective observational study of 65 patients at tertiary care level hospital. Subjects and Methods: After balanced general anesthesia, patients were intubated with high volume low-pressure ET.TEE probe was then inserted with gentle jaw thrust. CP was measured by standard invasive pressure monitoring device at four points: T1 at baseline before TEE probe insertion; T2 maximum CP noted at TEE probe insertion; T3 at 5 min post TEE probe insertion; and T4 at post-TEE exam. Statistical Analysis Used: CP was compared between pairs of time points (T1 vs. T2; T1 vs. T3; and T1 vs. T4) using Mann-Whitney U test. Factors predicting CP >30 cm of H2O at T4 were assessed by backward stepwise regression. Results: CP (mean ± S.D.) at T1, T2, T3, and T4 was 22 ± 3, 38 ± 10, 30 ± 6, and 30 ± 7, respectively. CP increased significantly from T1 to T2 (P < 0.001), T1 to T3 (P < 0.001), and T1 to T4 (P < 0.001). There were 26 patients (40%) with CP >30 cm of H2O at end of TEE exam (T4). On multivariate analysis baseline, CP (T1) >20 cm of H2O was significantly associated with CP >30 cm of H2O at end of TEE exam with Odd's Ratio (OR) of 8.5 (1.76-41.06, P = 0.008). Conclusions: To conclude, the CP increases significantly with TEE probe insertion in 40% of patients exceeding a safe limit of 30 cm of H2O. The monitoring and optimization of CP is advisable.

Influence of time interval between coronary angiography to off-pump coronary artery bypass surgery on incidence of cardiac surgery associated acute kidney injury.

BACKGROUND AND AIMS: Cardiac surgery associated acute kidney injury (CSA-AKI) is serious complication after cardiac surgery. The time interval between coronary angiography (CAG) to coronary artery bypass surgery (CABG) is proposed as modifiable risk factor for reduction of CSA-AKI. The aim of this study was to assess influence of time interval between CAG to off-pump CABG (OPCABG) on incidence of CSA-AKI. METHODS: This was a retrospective observational study of 900 consecutive OPCABG patients who were classified into 2 groups based on time interval between CAG and OPCABG: ≤7 days or longer. RESULTS: The incidence of CSA-AKI was 24% (214/900) by Kidney Disease: Improving Global Outcomes (KDIGO) definition. The incidence of CSA-AKI was not significantly different in two groups (22% in >7 days groupvs. 28% in ≤7 days group, P = 0.31). The factors independently associated with CSA-AKI were: Age (OR 1.04; P = 0.002), baseline creatinine (OR 1.99,; P = 0.03), moderate LV dysfunction (OR 1.64,; P = 0.007) and blood transfusion (OR 3.3,; P < 0.001), but not the time interval between CAG and OPCABG. The incidence of CSA-AKI was highest in patients with creatinine clearance (CC) <50 mL/min when OPCABG was performed ≤7 days of CAG (16/38; 42%, OR 2.7, 1.4-5.4; P = 0.005) compared to lowest incidence of CSA-AKI in patients with CC >50 mL/min and OPCABG performed >7 days of CAG (114/543; 21%). CONCLUSION: This study demonstrated that there is no increased incidence of CSA-AKI if OPCABG is performed ≤7 days of CAG; but we recommend to postpone OPCABG for seven days if CC is <50 mL/min and there is no urgent indication for OPCABG in order to reduce incidence of CSA-AKI.

A survey of practices during cardiopulmonary bypass in India: An Indian association of cardiovascular and thoracic anesthesiologist endeavor.

Context: Cardiac anesthesiologists play a key role during the conduct of cardiopulmonary bypass (CPB). There are variations in the practice of CPB among extracorporeal technologists in India. Aims: The aim of this survey is to gather information on variations during the conduct of CPB in India. Settings and Design: This was an online conducted survey by Indian College of Cardiac Anaesthesia, which is the research and academic wing of the Indian Association of Cardiovascular Thoracic Anaesthesiologists. Subjects and Methods: Senior consultants heading cardiac anesthesia departments in both teaching and nonteaching centers (performing at least 15 cases a month) were contacted using an online questionnaire fielded using SurveyMonkey™ software. There were 33 questions focusing on institute information, perfusion practices, blood conservation on CPB; monitoring and anesthesia practices. Results: The response rate was 74.2% (187/252). Fifty-one (26%) centers were teaching centers; 18% centers performed more than 1000 cases annually. Crystalloid solution was the most common priming solution used. Twenty-three percent centers used corticosteroids routinely; methylprednisone was the most commonly used agent. The cardioplegia solution used by most responders was the one available commercially containing high potassium St. Thomas solution (55%), followed by Del Nido cardioplegia (33%). Majority of the responders used nasopharyngeal site to monitor intraoperative patient temperature. Antifibrinolytics were commonly used only in patients who were at high risk for bleeding by 51% of responders, while yet, another 39% used them routinely, and 11% never did. About 59% of the centers insist on only fresh blood (<7 days old) when blood transfusion was indicated. The facility to use vaporizer on CPB was available in 62% of the centers. All the teaching centers or high volume centers in India had access to transesophageal echocardiography probe and echo machine, with 51% using them routinely and 38% using them at least sometimes. Conclusions: There is a wide heterogeneity in CPB management protocols among various Indian cardiac surgery centers. The survey suggests that adherence to evidence-based and internationally accepted practices appears to be more prevalent in centers that have ongoing teaching programs and/or have high volumes, strengthening the need to devise guidelines by appropriate body to help bring in uniformity in CPB management to ensure patient safety and high quality of clinical care for best outcomes.

Mitral Annular Plane Systolic Excursion: A Simple, Reliable Echocardiographic Parameter to Detect Left Ventricular Systolic Dysfunction in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting with Transesophageal Echocardiography.

OBJECTIVES: This study's objective was to test the hypothesis that transesophageal echocardiography (TEE)-based mitral annular plane systolic excursion (MAPSE) measurement is useful in perioperative settings to detect left ventricular (LV) systolic dysfunction in patients undergoing off-pump coronary artery bypass grafting (OPCAB). DESIGN: Retrospective observational study. SETTING: Tertiary-care level hospitals. PARTICIPANTS: The study comprised 116 patients undergoing OPCAB to obtain cutoffs of MAPSE to detect LV dysfunction. These cutoffs were validated in another 105 patients from 2 other institutions. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In 116 patients who had undergone OPCAB during the study period with TEE monitoring, MAPSE was measured post hoc at the lateral and septal mitral (and average) annulus using the software tool M.mode.ify (http://www.ultrasoundoftheweek.com/M.mode.ify). Receiver operating curves were constructed to obtain cutoff values of MAPSE at the lateral and septal (and average) annulus of the mitral valve to predict LV systolic dysfunction, which was defined by an ejection fraction <52% for men and <54% for women as measured using the biplane method of disks. These cutoff values then were validated in another 105 patients. LV systolic dysfunction was present in 43% patients. Youden's index values of 9mm for lateral MPASE (area under the receiver operating curve [AUC] 0.93 [confidence interval {CI} 0.87-0.97]; p < 0.0001); 7mm for septal MAPSE (AUC 0.87 [CI 0.79-0.92]; p < 0.0001); and 9mm for average MAPSE (AUC 0.92 [CI 0.86-0.96]; p < 0.0001) were obtained. These cutoffs were statistically significant in the validation cohort (p < 0.0001) with an AUC of 0.84 (CI 0.75-0.90), sensitivity of 86.2%, specificity of 80.8%, positive predictive value of 84.8%, and negative predictive value of 82.6%. CONCLUSIONS: MAPSE is a simple, rapid, and reliable method to detect LV dysfunction using TEE in patients undergoing OPCAB. Its use as screening tool for LV dysfunction is recommended.

Impact of preoperative pulmonary arterial hypertension on early and late outcomes in patients undergoing valve surgery for rheumatic heart disease.

BACKGROUND AND AIMS: There is conflicting evidence on adverse effect of Pulmonary Arterial Hypertension (PAH) on outcomes after cardiac surgery for rheumatic heart disease (RHD). The authors studied Indian patients with RHD and preoperative PAH, who undergo cardiac surgery with a hypothesis that they have poor short and long-term outcomes. METHODS: This was a retrospective observational study of 407 patients. The patients were divided in three groups based on PAH estimated on echocardiograph as; no or mild PAH (pulmonary artery systolic pressure (PASP) <30 mm of Hg); moderate PAH (PASP 31-55 mm of Hg) and severe PAH (PASP >55 mm of Hg). The primary endpoint was in-hospital mortality and major morbidities; while secondary endpoint was long-term survival. RESULTS: In-hospital mortality was 24 (5.9%); and was not different in patients with severe, (9.1%), moderate (4.5%) or mild PAH (2.8%) (P = 0.09). Patients with severe PAH had higher incidence of prolonged ventilation (P = 0.007). Factors independently associated with mortality were; >2-packed cell transfusion, prolonged ventilation and acute kidney injury but not moderate and severe PAH. Patients with mitral stenosis (MS) and severe PAH had significantly higher mortality as compared to no or mild PAH (P = 0.03) on long-term follow-up [81.37% (mean duration 19.40 ± 14.10 months)], mortality was 8% and not statistically different (P = 0.25) across PAH categories. CONCLUSION: Moderate and severe PAH does not affect short and long term outcomes of patients undergoing valve surgery for RHD. Patients with MS with severe PAH had higher mortality compared to those with no PAH.

Are cardiac surgical patients at increased risk of difficult intubation?

BACKGROUND AND AIMS: Safe airway management is the cornerstone of contemporary anaesthesia practice, and difficult intubation (DI) remains a major cause of anaesthetic morbidity and mortality. The surgical category, particularly cardiac surgery as a risk factor for DI has not been studied extensively. The aim of this study was to test the hypothesis whether cardiac surgical patients are at increased risk of DI. METHODS: During the study, 627 patients (329 cardiac and 298 non-cardiac surgical) were enrolled. Pre-operative demographic and other variables associated with DI were assessed. Patients with Cormack Lehane grade III and IV or use of bougie in Cormack grade II were defined as DI. The incidence of anticipated and unanticipated DI was assessed. Factors associated with DI were described using univariate and multivariate logistic regression models. RESULTS: The overall incidence of DI was 122/627 (19.46%). The incidence of DI was higher in cardiac surgery patients (24%) as compared to non-cardiac surgery patients (14.4% P = 0.002). On multivariate analysis, factors independently associated with DI were greater age, male sex, higher Mallampati grade, and anticipated DI, but not cardiac surgery. The incidence of unanticipated DI was 48.1% and 53.4% in cardiac and non-cardiac surgery patients, respectively. CONCLUSION: Although there was a higher incidence of DI in cardiac surgical patients, cardiac surgery is not an independent risk factor for DI. Rather, other factors play more important role. About half of the DI both in cardiac and non-cardiac surgeries were unanticipated.

Effect of Perioperative Pregabalin on Postoperative Quality of Recovery in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting (OPCABG): A Prospective, Randomized, Double-Blind Trial.

OBJECTIVES: Use of pregabalin is increasing in cardiac surgical patients. However, studies using comprehensive scoring systems are lacking on the drug's impact on postoperative recovery. The authors tested the hypothesis that perioperative oral pregabalin improves the postoperative quality of recovery as assessed using the Quality of Recovery (QoR-40) questionnaire in patients undergoing off-pump coronary artery bypass grafting (OPCABG). DESIGN: This was a randomized, double-blind, placebo-controlled study. SETTINGS: Tertiary-care hospital. PARTICIPANTS: Patients undergoing OPCABG. INTERVENTIONS: Patients were assigned randomly to the following 2 groups: the pregabalin group (those who received pregabalin, 150 mg capsule orally, 1 hour before surgery and 2 days postoperatively [75 mg twice a day] starting after extubation; n = 37); and the control group (those who received 2 similar-looking multivitamin capsules at similar times; n = 34). The QoR-40 scores were noted preoperatively and 24 hours after extubation. MEASUREMENTS AND MAIN RESULTS: Both groups were comparable in terms of preoperative patient characteristics and baseline QoR-40 scores. Global scores were significantly improved in the pregabalin group compared with the control group in the postoperative period (177±9 v 170±9; p = 0.002). QoR-40 values in the dimensions of emotional state (p = 0.005), physical comfort (p = 0.04), and pain (p = 0.02) were improved in the pregabalin group. CONCLUSIONS: Perioperative pregabalin improved postoperative quality of recovery as assessed using the QoR-40 questionnaire in patients undergoing OPCABG. Perioperative pregabalin offered advantages beyond better pain control, such as improved physical comfort and better emotional state; therefore, the drug's use in the perioperative period is recommended.

Variations of transesophageal echocardiography practices in India: A survey by Indian College of Cardiac Anaesthesia.

CONTEXT: Use of perioperative transesophageal echocardiography (TEE) has expanded in India. Despite attempts to standardize the practice of TEE in cardiac surgical procedures, variation in practice and application exists. This is the first online survey by Indian College of Cardiac Anaesthesia, research and academic wing of the Indian Association of Cardiovascular Thoracic Anaesthesiologists (IACTA). AIMS: We hypothesized that variations in practice of intraoperative TEE exist among centers and this survey aimed at analyzing them. SETTINGS AND DESIGN: This is an online survey conducted among members of the IACTA. SUBJECTS AND METHODS: All members of IACTA were contacted using online questionnaire fielded using SurveyMonkey™ software. There were 21 questions over four pages evaluating infrastructure, documentation of TEE, experience and accreditation of anesthesiologist performing TEE, and finally impact of TEE on clinical practice. Questions were also asked about national TEE workshop conducted by the IACTA, and suggestions were invited by members on overseas training. RESULTS: Response rate was 29.7% (382/1222). 53.9% were from high-volume centers (>500 cases annually). TEE machine/probe was available to 75.9% of the respondents and those in high-volume centers had easier (86.9%) access. There was poor documentation of preoperative consent (23.3%) as well as TEE findings (66%). Only 18.2% of responders were board qualified. Almost 90% of the responders felt surgeons respected their TEE diagnosis. Around half of the responders felt that new intraoperative findings by TEE were considered in decision-making in most of the cases and 70% of the responders reported that surgical plan was altered based on TEE finding more than 10 times in the last year. Despite this, only 5% of the responders in this survey were monetarily awarded for performing impactful skill of TEE. Majority (57%) felt that there is no need for overseas training for Indian cardiac anesthesiologists. CONCLUSIONS: In this survey of members of the IACTA, use of TEE has increased substantially, but still a lot of variations in practice patterns exist in India. There is urgent need for improving TEE certification and upgrade documentation standards, motivate use of TTE across all centers, promote awareness and usefulness of TEE use among surgical fraternity, monitor impact of TEE, and support separate remuneration policy in India.

Intraoperative conversion to on-pump coronary artery bypass grafting is independently associated with higher mortality in patients undergoing off-pump coronary artery bypass grafting: A propensity-matched analysis.

CONTEXT: One of the main limitations of off-pump coronary artery bypass grafting (OPCAB) is the occasional need for intraoperative conversion (IOC) to on-pump coronary artery bypass grafting. IOC is associated with a significantly increased risk of mortality and postoperative morbidity. The impact of IOC on outcome cannot be assessed by a randomized control design. AIMS: The objective of this study was to analyze the incidence, risk factors, and impact of IOC on the outcome in patients undergoing OPCAB. SETTINGS AND DESIGN: Three tertiary care level hospitals; retrospective observational study. SUBJECTS AND METHODS: This retrospective observational study included 1971 consecutive patients undergoing  OPCAB from January 2012 to October 2015 at three tertiary care level hospitals by four surgeons. The incidence, patient characteristics, cause of IOC, and its impact on outcome were studied. STATISTICAL ANALYSIS USED: The cohort was divided into two groups according to IOC. Univariate logistic regression was performed to describe the predictors of IOC. Variables that were found to be significant in univariate analysis were introduced into multivariate model, and adjusted odds ratio (OR) was calculated. To further assess the independent effect of IOC on mortality, propensity score matching with a 5:1 ratio of non-IOC to IOC was performed. RESULTS: The overall all-cause in-hospital mortality was 2.6%. IOC was needed in 128 (6.49%) patients. The mortality in the IOC group was significantly higher than non-IOC group (21 of 128 [16.4%] vs. 31 of 1843 [1.7%], P = 0.0001). The most common cause for IOC was hemodynamic disturbances during grafting to the obtuse marginal artery (51/128; 40%). On multivariate logistic regression analysis, left main disease, pulmonary hypertension, and mitral regurgitation independently predicted IOC. We obtained a propensity-matched sample of 692 patients (No IOC 570; IOC 122), and IOC had OR of 16.26 (confidence interval 6.3-41; P < 0.0001) for mortality in matched population. CONCLUSIONS: Emergency IOC increases odds for mortality by 16-fold. Hence, identification of patients at higher risk of IOC may improve the outcome.

Monitoring diastolic dysfunction using a simplified algorithm in patients undergoing off-pump coronary artery bypass grafting surgery.

CONTEXT: Left ventricle diastolic dysfunction (LVDD) is gaining importance as useful marker of mortality and morbidity in cardiac surgical patients. Different algorithms have been proposed for the intraoperative grading of DD. Knowledge of the particular grade of DD has clinical implications with the potential to modify therapy, but there is a paucity of literature on the role of diastolic function evaluation during off-pump coronary artery bypass grafting (OPCABG) surgery. AIMS: The aim of this study was to monitor changes in LVDD using simplified algorithm proposed by Swaminathan et al. in patients undergoing OPCABG. SETTINGS AND DESIGN: The study was conducted in a tertiary care level hospital; this was a prospective, observational study. SUBJECTS AND METHODS: Fifty consecutive patients undergoing OPCABG were enrolled. Hemodynamic and echocardiographic parameters were measured at 6 stages in every patient namely after anesthetic induction (baseline), during left internal mammary artery (LIMA) to left anterior descending (LAD) grafting (LIMA → LAD), saphenous vein graft (SVG) to obtuse marginal (OM) grafting (SVG → OM), SVG to posterior descending artery (PDA) grafting (SVG → PDA), during proximal anastomosis of SVG to aorta, and postprotamine. The patients were classified in grades of LVDD as per simplified algorithm proposed by Swaminathan et al. using only intraoperatively measured E and E'. RESULTS: The success rate of measurement and classification of LVDD was 98.92% (277 out of 280 measurements). The grades of LVDD varied significantly as per surgical steps with maximum downgrading occurring during OM and LAD grafting. During OM grafting, none of the patients had normal diastolic function while 29% of patients exhibited restrictive pattern (Grade 3 LVDD). Patients with normal baseline LV diastolic function also exhibited downgrading during OM and LAD grafting. Postprotamine, 37% of patients with normal baseline diastolic function continued to exhibit some degree of DD. CONCLUSIONS: The LVDD changes dynamically during various stages of OPCABG, which can be successfully monitored with simplified algorithm.