Impact of previous REnal TRansplantation on the mid-term renal Outcome after CARdiac surgery: the RETROCAR trial.

BACKGROUND: Acute kidney injury (AKI) is one of the most common complications after cardiac surgery with cardiopulmonary bypass (CPB). Renal transplant recipients (RTRs) have a higher risk of cardiac surgery-associated AKI (CSA-AKI). A relationship has been strongly suggested between AKI and poor long-term graft survival. The main objective was to evaluate the impact of on-pump cardiac surgery on the 1-year renal allograft survival rate. METHODS: The study population consisted of 37 RTRs and 56 non-RTRs who underwent cardiac surgery between 1 January 2010 and 31 December 2019. They were matched according to age, sex, preoperative glomerular function, diabetes and type of surgery. The primary composite outcome was renal survival, defined as patient survival without the requirement for permanent dialysis or new kidney transplantation at 1 year after surgery. RESULTS: The renal survival rate was significantly lower in the RTR group than in the non-RTR group [81% versus 96%; odds ratio 0.16 (95% confidence interval 0.03-0.82), P = .03]. The proportion of patients who returned to permanent dialysis was higher in the RTR group than in the non-RTR group (12% versus 0%; P = .02). The proportion of patients with severe AKI was also higher in the RTR group. At 1 year after surgery, serum creatinine level, glomerular filtration rate and all-cause mortality rates were comparable between both groups. CONCLUSION: Patients with a functional renal allograft have a low 1-year renal allograft survival rate after cardiac surgery with CPB. In addition, these patients have significant risks of AKI and acute kidney disease after open-heart surgery.

Risk Factors of Midterm Mortality After Aortic Valve Replacement for Severe Calcified Tricuspid Aortic Valve Stenosis: A retrospective analysis of Perioperative Events Assessment in Adult Cardiac surgery (PESSAC) Registry.

OBJECTIVE: The European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) initially developed for predicting early postoperative mortality of all types of cardiac surgery, is less able to predict, more specifically, long-term outcomes after aortic valve replacement (AVR). The study authors here evaluated the risk factors for three-year mortality after isolated aortic valve replacement (AVR) for severe calcified tricuspid aortic valve stenosis and compared them with EuroSCORE II to predict long-term outcomes. DESIGN: A retrospective study. SETTING: A university teaching hospital. PARTICIPANTS: This study included 1,101 adults who underwent isolated AVR for severe calcified tricuspid aortic valve stenosis between September 2010 to June 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was that of three-year all-cause mortality after AVR. By three years, 168 patients (15.3%) had died. Risk factors for all-cause mortality were: male gender (odds ratio [OR] = 1.78; 95% confidence interval [CI] = 1.21-2.62; p < 0.01), peripheral arterial disease (OR = 1.77; 95% CI = 1.08-2.92; p = 0.03), age (OR = 1.06 per year increase; 95% CI =1.04-1.09; p < 0.01), pulmonary artery systolic pressure (OR = 1.02 per mmHg increase; 95% CI = 1.01-1.03; p < 0.01), platelet count (OR = 1.003 per G/L increase; 95% CI = 1.000-1.005; p = 0.04), and valve area (OR = 0.97 per cm²/m² increase; 95% CI= 0.95-0.99; p < 0.01). The area under the receiver operating characteristic curves were 0.67 (95% CI = 0.60-0.75) and 0.60 (95% CI = 0.56-0.65) for the authors' logistic regression model and EuroSCORE II, respectively (p = 0.11). CONCLUSIONS: The study authors identified six independent risk factors for three-year mortality after isolated AVR. The logistic regression model had relatively modest predictive performance for three-year mortality.

U-shaped relationship between pre-operative plasma fibrinogen levels and severe peri-operative bleeding in cardiac surgery.

BACKGROUND: An inverse linear relationship has been reported between pre-operative fibrinogen levels and postoperative blood loss in cardiac surgery. However, recently high pre-operative fibrinogen levels have also been reported to be associated with increased blood transfusion and re-operation. OBJECTIVE: We tested the hypothesis that the relationship between pre-operative fibrinogen levels and severe peri-operative bleeding is not linear. DESIGN: A large-scale (n = 3883) single-centre retrospective study. SETTING: A tertiary care teaching hospital. PATIENTS: We analysed data from our institutional database which includes all patients above 18 years who underwent on-pump cardiac surgery through a sternotomy between September 2010 and May 2014. MAIN OUTCOME MEASURES: Peri-operative severe bleeding adapted from the Universal Definition of Peri-operative Bleeding, class 3 or 4. The relationship between pre-operative fibrinogen levels and peri-operative severe bleeding was analysed by binary logistic regression. A cubic B-spline transformation was used to estimate the relationship between pre-operative fibrinogen level associated with excessive peri-operative bleeding. RESULTS: Severe peri-operative bleeding was observed in 957 (24.6%) patients. An L-shaped relationship was observed between pre-operative fibrinogen levels and 24-h postoperative blood loss. The relationship between pre-operative fibrinogen levels and severe peri-operative bleeding (i.e. Universal Definition of Peri-operative Bleeding class 3 or 4) was U-shaped: the risk of severe peri-operative bleeding bottomed at 3.3 g l when the upward sloping curve started at 5.8 g l with a steeper increase above 8.2 g l. CONCLUSION: We reported a U-shaped relationship between severe peri-operative bleeding and pre-operative fibrinogen levels. While a low-level of fibrinogen appears to be associated with a high risk of bleeding, a high level does not necessarily protect the patient against such a risk and could even be a risk factor for peri-operative bleeding.

Intraoperative changes in blood lactate levels are associated with worse short-term outcomes after cardiac surgery with cardiopulmonary bypass.

BACKGROUND: A high perioperative blood lactate level has been reported to be associated with poor outcomes after cardiac surgery. More than isolated peaks of lactate values, it should be more interesting to take into account changes in intraoperative blood lactate level (∆Lact). This large-scale retrospective study evaluated the relationship between ∆Lact and overall intensive care unit morbidity and 30-day all-cause mortality. METHODS: Perioperative data from consecutive patients undergoing on-pump cardiac surgery between September 2010 and June 2016 were retrospectively analysed through our institutional database including clinical, transfusion and laboratory test results implemented prospectively by physicians. Blood lactate levels were initially measured after induction of anaesthesia (baseline) and periodically during the surgery. The ∆Lact was defined as the difference between the highest intraoperative blood lactate and the baseline lactate level and offered the opportunity to stratify patients into four subgroups: ⩽0, 0.1-0.9, 1-1.9 and ⩾2 mmol L-1. RESULTS: From the 7,795 patients found eligible during the study period, 7,447 patients were analysed. The median ∆Lact of our patients was 0.6 (0.3-1) mmol L-1. Most of the studied patients (65.9%) exhibited a ∆Lact between 0.1 and 0.9 mmol L-1. A concentration-dependent relationship was observed between ∆Lact and intensive care unit morbidity and 30-day mortality. After adjustment for co-variables, all ∆Lact > 0 was associated with an increase in overall intensive care unit morbidity. An independent relationship was also found between ∆Lact and 30-day mortality as of a 1 mmol L-1 increase. CONCLUSION: Our results suggest that ∆Lact is associated with poor short-term outcomes in adult cardiac surgical patients.

Feasibility of Automated Propofol Sedation for Transcatheter Aortic Valve Implantation: A Pilot Study.

BACKGROUND: Recently, several trials have shown that closed-loop sedation is feasible. No study has used automated sedation in extremely frail patients, such as those scheduled for transcatheter aortic valve implantation (TAVI). We developed and tested a novel automated sedation system for this kind of population and surgery. The system integrates a decision support system that detects respiratory and hemodynamic events via smart alarms, which provide pertinent/related clinical suggestions and treatment options. The main objective was the feasibility of closed-loop sedation, defined as successful automated sedation without manual override. Secondary qualitative observations were clinical and controller performance. METHODS: Twenty patients scheduled for elective TAVI were enrolled. Sedation was administered via a closed-loop delivery system designed for propofol. The clinical performance of sedation was the efficacy to maintain a bispectral index (BIS) of 65. To evaluate the sedation performance, BIS values were stratified into 4 categories: excellent, very good, good, and inadequate sedation control, defined as BIS values within 10%, ranging from 11% to 20%, ranging from 21% to 30%, or >30% from the target value, respectively. The controller performance was calculated using Varvel parameters. Critical respiratory and hemodynamic events were documented. The former was defined as peripheral oxygen saturation <92% and/or respiratory rate <8/min, whereas the latter was considered a mean arterial pressure <60 mm Hg and/or heart rate <40 bpm. RESULTS: Automated sedation was successful in 19 patients undergoing TAVI. One patient was excluded from the final analysis because of conversion to general anesthesia. The secondary observations revealed that the clinical performance allowed an excellent to good control during 69% (99% confidence interval, 53%-77%; interquartile range, 59%-79%) of the sedation time. Fifteen patients presented critical respiratory episodes, with a median of 3 events per hour of sedation. Six patients presented critical hemodynamic episodes, with a median of 2 events per hour of procedure. CONCLUSIONS: The automated closed-loop sedation system tested could be used successfully for patients scheduled for a TAVI procedure. The results showed a satisfactory clinical performance of sedation control.

Impact of age on anaesthesiologists' competence: A narrative review.

The international anaesthesia community is getting older, in line with trends worldwide, and as men and women age there is the risk that psychophysiological decline could have an impact on clinical practice. Impairment of technical and nontechnical skills could have a negative impact on patients' safety and outcomes. The ageing process may not necessarily go hand-in-hand with a predictable pattern of decreased competence as not all aspects of functional decline are affected at the same rate and to the same extent. The development of simulation has provided a means of detecting and perhaps reversing the decline in ability associated with age. The introduction of recertification based on an assessment of competence at simulation sessions could play a crucial role in maintaining a high standard of patient care and an appropriate level of patient safety.

Validation of a single-platform, volumetric, CD45-assisted PanLeucogating Auto40 flow cytometer to determine the absolute number and percentages of CD4 T cells in resource-constrained settings using Cameroonian patients' samples.

The study evaluated the single-platform, volumetric, CD45-assisted PanLeucogating Auto40 flow cytometer (Apogee Flow Systems Ltd., Hemel Hempstead, United Kingdom) for CD4 T cell numeration, compared to the reference FACSCalibur flow cytometer. Results of absolute counts and percentages of CD4 T cells by Auto40 and FACSCalibur of 234 tripotassium EDTA (K3-EDTA)-blood samples from 146 adults and 88 children (aged from 18 months to 5 years), living in Yaoundé, Cameroon, were highly correlated (r(2) = 0.97 and r(2) = 0.98, respectively). The mean absolute bias and relative bias between Apogee Auto40 and FACSCalibur absolute CD4 T cell counts were +9.6 cells/µl, with limits of agreement from -251 to 270 cells/µl, and +4.1%, with limits of agreement from -16.1 to 24.4%, respectively. The mean absolute bias and relative bias between Apogee Auto40 and FACSCalibur CD4 T cell results expressed as percentages were +0.05% CD4 (95% confidence interval [CI], -0.03 to 0.41), with limits of agreement from -6.0 to 5.9% CD4, and +1.0%, with limits of agreement from -32.3 to 34.4%, respectively. The Auto40 counting allowed identification of the majority of adults with CD4 T cell counts below 200 cells/µl (sensitivity, 87%; specificity, 98%) or below 350 cells/µl (sensitivity, 92%; specificity, 98%) and of children with CD4 T cell counts below 750 cells/µl (sensitivity, 82%; specificity, 98%) or below 25% CD4(+) (sensitivity, 96%; specificity, 99%). The Auto40 analyzer is a reliable alternative flow cytometer for CD4 T lymphocyte enumeration to be used in routine immunological monitoring according to the WHO recommendations for HIV-infected adults as well as children living in resource-constrained settings.