On-table Extubation After Minimally Invasive Cardiac Surgery: A Retrospective Observational Pilot Study.

OBJECTIVE: To assess the safety of "on-table" extubation after minimally-invasive heart valve surgery. DESIGN: A single-center retrospective observational study. SETTING: At a tertiary referral academic hospital. PARTICIPANTS: Patients who underwent nonemergent isolated heart valve surgery through a minithoracotomy approach between January 2016 and August 2021. INTERVENTION: All patients were treated by 1 of the 6 cardiac anesthesiologists of the hospital. Only some of them practiced "on-table" extubation, and the outcome of patients extubated "on-table" was compared to those extubated in the intensive care unit (ICU). MEASUREMENT AND MAIN RESULTS: The primary outcome was the occurrence of any postoperative respiratory complication during the entire hospital stay. Secondary outcomes included the use of inotropes and vasopressors, de novo atrial fibrillation, and lengths of stay in the ICU and the hospital. A total of 294 patients met inclusion criteria, of whom 186 (63%) were extubated "on-table." Cardiopulmonary bypass duration was significantly longer, and moderate intraoperative hypothermia was significantly more frequent in patients extubated in the ICU. After adjustment for these confounders and for the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II using a multivariate logistic model, no association was found between the extubation strategy and postoperative pulmonary complications (adjusted odds ratio = 0.84; 95% CI = 0.40-1.77; p = 0.64). "On-table" extubation was associated with a lower risk of postoperative pneumonia and fewer vasopressors requirements. CONCLUSION: "On-table" extubation was not associated with an increased incidence of respiratory complications. A randomized controlled trial is warranted to confirm these results and determine whether "on-table" extubation offers additional benefits.

Development and Validation of a Prediction Score for Low-Cardiac-Output Syndrome After Adult Cardiac Surgery.

OBJECTIVES: The authors aimed to develop a simple prediction score to help identify patients at high risk of low-cardiac-output syndrome after adult cardiac surgery. DESIGN: A single-center, retrospective, observational study. SETTING: At a tertiary hospital. PARTICIPANTS: Adult patients who underwent on-pump cardiac surgery between April 2016 and March 2021. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Among the 2,806 patients retained for final analyses, 355 (12.7%) developed low-cardiac-output syndrome. Using a stepwise backward variable selection procedure applied to a multivariate logistic regression, a prediction model, including 8 risk factors, could be identified-preoperative left ventricular ejection fraction, glomerular filtration rate <60 mL/min according to the Cockcroft formula or preoperative dialysis, combined surgery, nonelective surgery, mitral valve surgery for mitral valve regurgitation, history of extracardiac arteriopathy, preoperative hemoglobin <13 g/dL, and New York Heart Association functional class III or IV. A clinical prediction score was derived from the regression coefficients. The model had a good discriminative ability, with an area under the receiver operating characteristics curve of 0.8 (95% CI: 077-0.84). Using a threshold value of 5, the score had a 68% sensitivity, 79% specificity, a positive-predictive value of 33%, and a negative-predictive value of 94%. These results were validated on a validation sample using the bootstrap resampling technique. CONCLUSIONS: The authors developed a clinical score to facilitate the prediction of low- cardiac-output syndrome after adult cardiac surgery. This could help tailor patient management by contributing to the early identification of those at high risk of postoperative low cardiac output.

Cardiac Biomarkers and Prediction of Early Outcome After Heart Valve Surgery: A Prospective Observational Study.

OBJECTIVES: Circulating cardiac biomarkers may improve the prediction of long-term outcomes after cardiac surgery. The authors sought to assess if cardiac biomarkers also help better predict short-term morbidity. DESIGN: Prospective observational study. SETTING: Single academic hospital. PARTICIPANTS: A total of 250 patients undergoing aortic or mitral valve surgery with or without associated coronary artery bypass grafts. INTERVENTION: None MEASUREMENT AND MAIN RESULTS: Relationships between preoperative plasma concentrations of four cardiac biomarkers (sST2, Galectin-3, GDF-15, and NT-proBNP) and postoperative outcome were assessed using logistic regressions and Cox proportional hazards models. The primary outcome was a composite of 30-day mortality, an inotropic support longer than 48 hours and an initial length of stay in the intensive care >five days. Secondary outcome measures were postoperative acute kidney injury, inotropic support duration, lengths of intensive care unit and hospital stays, and 30-day and one-year mortality. No association was observed between any of the four cardiac biomarkers and the primary outcome. The preoperative levels of Galectin-3 (hazard ratio = 1.2; p < 0.001) and sST2 (hazard ratio = 1.01, p < 0.001) were significantly associated with one-year survival, and their addition to the EuroSCORE II significantly improved the prediction of one-year mortality (p < 0.001). Similarly, Galectin-3 was associated with postoperative acute kidney injury (odds ratio = 1.15, p = 0.001) and improved the prediction of this complication when added to the EuroSCORE II (p = 0.002). CONCLUSIONS: These results suggested that the ability of cardiac biomarkers to predict short-term outcome after cardiac surgery, though of interest, appears limited. Conversely, cardiac biomarkers may have the potential to refine the prediction of long-term outcome. Admittedly, all positive results were obtained on secondary outcomes and must be regarded with caution.

The Edmonton Frail Scale Improves the Prediction of 30-Day Mortality in Elderly Patients Undergoing Cardiac Surgery: A Prospective Observational Study.

OBJECTIVES: To investigate whether the Edmonton Frail Scale (EFS), a multidimensional frailty assessment tool, improves the prediction of 30-day or in-hospital mortality over the use of the European System for Cardiac Outcome Risk Evaluation (EuroSCORE) II alone. DESIGN: Single-center prospective observational study. SETTING: University hospital. PARTICIPANTS: Patients aged 75 years or older undergoing cardiac surgery between February 2014 and May 2017. INTERVENTION: No intervention was performed. The EFS was administered the day before surgery. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was 30-day or in-hospital mortality. Secondary endpoints were times to discharge from the intensive care unit (ICU) and from the hospital, discharge to a health care facility, and ability to return home by postoperative day 30. The EFS had a good discriminative ability for 30-day mortality (area under the receiver operating characteristic curve = 0.69; 95% confidence interval [CI], 0.56-0.82). Adding frailty, defined by an EFS ≥8, to the EuroSCORE II significantly improved the prediction of 30-day (p = 0.04) mortality. The integrated discrimination index was 0.03 (95% CI, 0.01-0.06, p = 0.01), meaning that the difference in predicted risk between patients who died and those who survived increased by 3% due to the addition of frailty determined by the EFS to the EuroSCORE II. Frailty also was associated significantly with a decreased cumulative probability of discharge from the ICU (p = 0.02) and an increased incidence of discharge to a health care facility (p = 0.01). CONCLUSION: The EFS has a good predictive ability for 30-day mortality after cardiac surgery in elderly patients and improves the prediction of 30-day mortality over the use of the EuroSCORE II.

Low Cardiac Output Syndrome After Adult Cardiac Surgery: Predictive Value of Peak Systolic Global Longitudinal Strain.

BACKGROUND: Peak systolic global longitudinal strain (GLS) is increasingly used to quantify left ventricular systolic function. The primary objective of this study was to assess whether GLS obtained during intraoperative transesophageal echocardiogram, performed before cardiopulmonary bypass, improves the prediction of postoperative low cardiac output syndrome (LCOS) after adult cardiac surgery. METHODS: GLS from 275 patients undergoing on-pump cardiac surgery was calculated retrospectively using two-dimensional- speckle tracking echocardiography (aCMQ module from Qlab software version 10.5, Philips Medical, Brussels, Belgium). LCOS was defined as the need for inotropic or mechanical circulatory support for >24 hours postoperatively. Patient and procedure characteristics associated with LCOS at the univariable level (P ≤ .05) were entered into a forward stepwise logistic regression to create a first predictive model. A second model was created by adding GLS. The 2 models were compared using the likelihood-ratio test, the area under the receiver operating characteristic (ROC) curve, and the integrated discrimination index. The optimal cutoff value of GLS associated with LCOS was determined by maximizing the Youden index of the ROC curve. Secondary outcomes included time until complete weaning from inotropes, discharge from the intensive care unit and from the hospital, and 30-day mortality. RESULTS: GLS was significantly associated with LCOS (P < .001) at the univariable level. Predictors of LCOS retained in the first model were cardiopulmonary bypass duration, decreased left ventricular ejection fraction, mitral valve surgery, and New York Heart Association functional class III or IV. Adding the GLS value improved the prediction of LCOS (P = .02). However, the area under the ROC curve did not differ between the 2 models (0.83; 95% confidence interval [CI], 0.77-0.99 vs 0.84; 95% CI, 0.79-0.90; P = .15). The integrated discrimination index associated with addition of GLS was 0.02 (P = .046), meaning that the difference in predicted risk between patients with and without LCOS increased by 2% after adding GLS. A GLS cutoff value of -17% (95% CI, -18.8% to -15.3%) was found to best identify LCOS. After adjusting for covariates included in model 1, a lower GLS value was significantly associated with a lower cumulative probability of weaning from inotropes postoperatively (hazard ratio, 0.90; 95% CI, 0.82-0.97; P = .01). No association was found between GLS and other secondary outcome measures. CONCLUSIONS: GLS is an independent predictor of LCOS after on-pump cardiac surgery. Its incremental value over other established risk factors for postoperative LCOS is, however, limited.

Efficacy of the RemoweLL cardiotomy reservoir for fat and leucocyte removal from shed mediastinal blood: a randomized controlled trial.

INTRODUCTION: Re-transfusion of lipid particles and activated leucocytes with shed mediastinal blood (SMB) can aggravate cardiopulmonary bypass-associated inflammation and increase the embolic load. This study evaluated the fat and leucocyte removal capacity of the RemoweLL cardiotomy reservoir. METHODS: Forty-five patients undergoing elective on-pump cardiac surgery were randomly allocated to filtration of SMB using the RemoweLL or the Admiral cardiotomy reservoir. The primary outcome was a drop in leucocytes and lipid particles obtained with the two filters. The effect of the filters on other blood cells and inflammatory mediators, such as myeloperoxidase (MPO), was also assessed. RESULTS: The RemoweLL cardiotomy filter removed 16.5% of the leucocytes (p<0.001) while no significant removal of leucocytes was observed with the Admiral (p=0.48). The percentage reductions in lipid particles were similar in the two groups (26% vs 23%, p=0.2). Both filters similarly affected the level of MPO (p=0.71). CONCLUSION: The RemoweLL filter more effectively removed leucocytes from SMB than the Admiral. It offered no advantage in terms of lipid particle clearance.

The place of viscoelastic testing in clinical practice.

Hellmut Hartert was the first person to exploit the viscoelastic properties of clotting blood to measure blood coagulation in 1948. Since then, the technology has improved, allowing these analyses to be performed as point-of-care tests with immediately-available results. The addition of several activators and inhibitors to the original assay creates a panel of tests able to quantify the different aspects of blood clotting that can rival conventional laboratory assays. However, although much progress has been made, the standardization and validation of these tests still need improvement. Viscoelastic analyses of blood coagulation are mainly used to guide haemostatic therapy in bleeding patients and have proven superior to standard clotting tests in some circumstances. There is potential to extend their use to other areas, such as drug monitoring, and diagnosis and management of congenital bleeding disorders. The forthcoming cartridge-based assays are expected to improve the reliability and usability of viscoelastic assays of blood coagulation but high quality clinical trials remain urgently needed to determine their exact place, benefit and cost effectiveness.

Hydroxyethyl Starch 130/0.4 and the Risk of Acute Kidney Injury After Cardiopulmonary Bypass: A Single-Center Retrospective Study.

OBJECTIVES: To investigate whether using hydroxyethyl starch (HES) 130/0.4 as a pump prime and for intraoperative fluid therapy is associated with postoperative acute kidney injury (AKI) after adult cardiac surgery. DESIGN: Retrospective observational study. SETTING: University hospital, single center. PARTICIPANTS: Six hundred six adult patients who underwent on-pump cardiac surgery between April 2013 and June 2014 were included. INTERVENTIONS: Until July 2013, balanced HES 130/0.4 (Volulyte(®), Fresenius Kabi AG, Bad Homburg, Germany) was used both as a pump prime (1,500 mL) and for intraoperative fluid therapy (1,000 mL). From August 2013, HES was replaced entirely by a balanced crystalloid solution (Plasma-Lyte A, Baxter, Lessines, Belgium). MEASUREMENTS AND MAIN RESULTS: The primary endpoint was the incidence of postoperative AKI during the first 48 postoperative hours, determined using the Acute Kidney Injury Network classification. Secondary outcomes included kidney function at postoperative day 7, postoperative dialysis or hemofiltration, postoperative pulmonary complications, lengths of intensive care unit and hospital stays, postoperative fluid balance and urinary output, surgical revision for bleeding, and 30-day mortality. Multivariable logistic regression was used to adjust for confounders. AKI occurred in 9.5% of crystalloid patients and in 21.5% of HES patients. Patients who received HES were about twice as likely to develop postoperative AKI as those treated with crystalloids (adjusted OR 2.26; 95% CI, 1.40-3.80; p = 0.02). HES patients also had a significantly more positive fluid balance and a lower urinary output during the first 48 postoperative hours. The incidence of surgical revision for bleeding was greater in the HES group (4.6% v 1.4%, p = 0.02). CONCLUSION: This study suggested that using balanced HES 130/0.4 as a pump prime and for intraoperative fluid therapy in adult patients undergoing on-pump cardiac surgery was associated with a greater incidence of AKI during the early postoperative period.

Impact of 6 % hydroxyethyl starch (HES) 130/0.4 on the correlation between standard laboratory tests and thromboelastography (TEG®) after cardiopulmonary bypass.

BACKGROUND: Hydroxyethyl starches (HES) affect the results of thromboelastography (TEG®). We sought to determine whether using HES rather than crystalloids for cardiopulmonary bypass (CPB) prime and intraoperative fluid therapy changes the TEG cutoff values best identifying patients with a low platelet count or a low fibrinogen level after CPB. METHODS: Data from 96 patients who had on-pump cardiac surgery, a TEG® (kaolin-heparinase) and standard investigations of blood clotting performed after separation from CPB and protamine administration were retrospectively reviewed. Patients were assigned to the HES or crystalloid group according to whether balanced 6% HES 130/0.4 or balanced crystalloids were used for intraoperative fluid therapy and pump prime. Mutlivariable linear regression models with computation of the standardized regression coefficients were used to identify independent associations between the four main TEG parameters (R time, alpha angle, K time and MA) and the type of fluid used, the INR, the aPTT, the fibrinogen level and the platelet count. Receiver-operating-characteristic curves were used to assess the effect of HES on the ability of TEG parameters to identify patients with a platelet count<80.000µl(-1) or a fibrinogen level<1.5 gr l(-1) and on the cutoff values best identifying these patients. RESULTS: The type of fluid used significantly affected the MA (P<0.001), the K time (P<0.001) and the alpha angle (P<0.001) regardless of the results of the standard clotting tests. According to standardized ß regression coefficients the platelet count and the type of fluid used were stronger predictors of the MA, the alpha angle and the K time than the fibrinogen level. MA better predicted platelets<80.000µl(-1) than K time and alpha angle (P=0.023). The best cutoff value of MA identifying patients with platelets<80.000µl(-1) was 62mm in the crystalloid group and 53mm in the HES group. MA, K time and alpha angle were poor predictors of the postoperative fibrinogen level. CONCLUSION: HES significantly changes the cutoff value of TEG® MA best identifying patients<80.000µl(-1) after on-pump cardiac surgery.

The effect of intraoperative 6% balanced hydroxyethyl starch (130/0.4) during cardiac surgery on transfusion requirements.

OBJECTIVES: To compare transfusion requirements in adult cardiac surgery patients when balanced hydroxyethyl starches (HES) (130/0.4) or balanced crystalloids is used for pump prime and intraoperative fluid therapy. DESIGN: Data were obtained retrospectively from medical records and perfusion charts. Matching based on propensity scores was used to adjust for potential confounders. SETTING: A university hospital. PARTICIPANTS: Adult patients undergoing cardiac surgery with the use of cardiopulmonary bypass. INTERVENTIONS: Allocation to one of the study groups according to whether balanced HES or balanced crystalloids was used for pump prime and intraoperative fluid therapy. MEASUREMENTS AND MAIN RESULTS: 240 propensity-matched patients were retained for final analyses. Forty-eight patients (40%) of the colloid group and 28 patients (23.3%) of the crystalloid group received blood products, with an odd ratio (95% CI) of 2.1(1.2-3.8 (P=0.009). After bypass HES patients had lower hemoglobin levels (8.4 [1.3] gr/dL vs 9.6 [2] gr/dL; P<0.001) and a higher cumulative chest drain output after 3 hours (180 [210] mL vs 140 [100] mL, P<0.001]. Heparinase thromboelastogram (TEG®) showed longer K times (2.5[1.1] vs 1.6[0.8], P<0.001) and lower maximal amplitudes (55.1[12.5] vs 63.4[9.8], P=0.008). CONCLUSIONS: HES patients required more transfusions, owing to greater hemodilution, HES-induced clotting disturbances, and bleeding.

Intravenous magnesium re-establishes neuromuscular block after spontaneous recovery from an intubating dose of rocuronium: a randomised controlled trial.

CONTEXT: Intravenous magnesium deepens non-depolarising neuromuscular block. OBJECTIVE: To assess whether intravenous magnesium has the potential to re-establish paralysis in patients who have just recovered from a non-depolarising neuromuscular block. DESIGN: Prospective randomised double-blind controlled study. PATIENTS: Twenty non-obese patients ranging in age from 18 to 80 years were enrolled. Exclusion criteria were a history of liver, kidney or neuromuscular disease and intake of medications interacting with neuromuscular blocking agents. INTERVENTION: After spontaneous recovery from an intubating dose of rocuronium had been achieved (train-of-four ratio ≥0.9), patients were given either a bolus dose of magnesium 50 mg kg(-1) intravenously or an equivalent volume of isotonic saline over 5 min. MAIN OUTCOME MEASURES: The train-of-four ratio was measured every minute until the end of surgery. The primary endpoint was the proportion of patients who experienced a decrease in train-of-four ratio following administration of magnesium or saline. RESULTS: Following infusion of the study solution, the train-of-four ratio decreased in all patients in the magnesium group in contrast to none in the saline group (P<0.001). On average, magnesium-induced train-of-four ratio depression reached a nadir of 0.49 after 10 min and lasted for 45 min. CONCLUSION: A bolus dose of intravenous magnesium 50 mg kg(-1) re-establishes a clinically relevant degree of muscle paralysis in patients who have just recovered from a non-depolarising neuromuscular block. TRIAL REGISTRATION: EudraCT.ema.europa.eu 2009-017372-24.

Ventilatory management during routine general anaesthesia.

Intraoperative hypoxaemia and postoperative respiratory complications remain the challenges of modern anaesthetic practice. Anaesthesia causes both depression of respiratory centres and profound changes of respiratory mechanics. Most anaesthetized patients consequently require mechanical ventilation and supplemental oxygen. Recent data suggest that intraoperative respiratory management of a patient can affect postoperative outcome. In this review, we briefly describe the mechanisms responsible for the impairment of intraoperative gas exchange and provide guidelines to prevent or manage hypoxaemia. Moreover, we discuss several aspects of mechanical ventilation that can be employed to improve patients' outcome.

Pressure-controlled ventilation does not improve gas exchange in morbidly obese patients undergoing abdominal surgery.

BACKGROUND: Morbid obesity results in marked respiratory pathophysiologic changes that may lead to impaired intraoperative gas exchange. The decelerating inspiratory flow and constant inspiratory airway pressure resulting from pressure-controlled ventilation (PCV) may be more adapted to these changes and improve gas exchanges compared with volume-controlled ventilation (VCV). METHODS: Forty morbidly obese patients scheduled for gastric bypass were included in this study. Total intravenous anesthesia was given using the target-controlled infusion technique. During the first intraoperative hour, VCV was used and the tidal volume was adjusted to keep end-tidal PCO(2) around 35 mmHg. After 1 h, patients were randomly allocated to 30-min VCV followed by 30-min PCV or the opposite sequence using a Siemens Servo 300. FiO(2) was 0.6. During PCV, airway pressure was adjusted to provide the same tidal volume as during VCV. Arterial blood was sampled for gas analysis every 15 min. Ventilatory parameters were also recorded. RESULTS: Peak inspiratory airway pressures were significantly lower during PCV than during VCV (P < 0.0001). The other ventilatory parameters were similar during the two periods of ventilation. PaO(2) and PaCO(2) were not significantly different during PCV and VCV. CONCLUSION: PCV does not improve gas exchange in morbidly obese patients undergoing gastric bypass compared to VCV.