Anthony J. Bastin

Acute kidney injury after cardiac surgery according to Risk/Injury/Failure/Loss/End-stage, Acute Kidney Injury Network, and Kidney Disease: Improving Global Outcomes classifications

PURPOSE The epidemiology of acute kidney injury (AKI) after cardiac surgery depends on the definition used. Our aims were to evaluate the Risk/Injury/Failure/Loss/End-stage (RIFLE) criteria, the AKI Network (AKIN) classification, and the Kidney Disease: Improving Global Outcomes (KDIGO) classification for AKI post-cardiac surgery and to compare the outcome of patients on renal replacement therapy (RRT) with historical data. METHODS Retrospective analysis of 1881 adults who had cardiac surgery between May 2006 and April 2008 and determination of the maximum AKI stage according to the AKIN, RIFLE, and KDIGO classifications. RESULTS The incidence of AKI using the AKIN and RIFLE criteria was 25.9% and 24.9%, respectively, but individual patients were classified differently. The area under the receiver operating characteristic curve for hospital mortality was significantly higher using the AKIN compared with the RIFLE criteria (0.86 vs 0.78, P = .0009). Incidence and outcome of AKI according to the AKIN and KDIGO classification were identical. The percentage of patients who received RRT was 6.2% compared with 2.7% in 1989 to 1990. The associated hospital mortality fell from 82.9% in 1989 to 1990 to 15.6% in 2006 to 2008. CONCLUSIONS The AKIN classification correlated better with mortality than did the RIFLE criteria. Mortality of patients needing RRT after cardiac surgery has improved significantly during the last 20 years.

Clinical Outcomes of Surgical Pulmonary Valve Replacement after Repair of Tetralogy of Fallot and Potential Prognostic Value of Preoperative Cardiopulmonary Exercise Testing

Background— Indications for surgical pulmonary valve replacement (PVR) after repair of tetralogy of Fallot have recently been broadened to include asymptomatic patients. Methods and Results— The outcomes of PVR in adults after repair of tetralogy of Fallot at a single tertiary center were retrospectively studied. Preoperative cardiopulmonary exercise testing was included. Mortality was the primary outcome measure. In total, 221 PVRs were performed in 220 patients (130 male patients; median age, 32 years; range, 16–64 years). Homografts were used in 117 patients, xenografts in 103 patients, and a mechanical valve in 1 patient. Early (30-day) mortality was 2%. Overall survival was 97% at 1 year, 96% at 3 years, and 92% at 10 years. Survival after PVR in the later era (2005–2010; n=156) was significantly better compared with survival in the earlier era (1993–2004; n=65; 99% versus 94% at 1 year and 98% versus 92% at 3 years, respectively; P=0.019). Earlier era patients were more symptomatic preoperatively (P=0.036) with a lower preoperative peak oxygen consumption (peak O2; P<0.001). Freedom from redo surgical or transcatheter PVR was 98% at 5 years and 96% at 10 years for the whole cohort. Peak O2, E/CO2 slope (ratio of minute ventilation to carbon dioxide production), and heart rate reserve during cardiopulmonary exercise testing predicted risk of early mortality when analyzed with logistic regression analysis; peak O2 emerged as the strongest predictor on multivariable analysis (odds ratio, 0.65 per 1 mL·kg−1·min−1; P=0.041). Conclusions— PVR after repair of tetralogy of Fallot has a low and improving mortality, with a low need for reintervention. Preoperative cardiopulmonary exercise testing predicts surgical outcome and should therefore be included in the routine assessment of these patients.

Biomarkers of lung injury after one‐lung ventilation for lung resection

Background and objective:  Acute lung injury contributes to the mortality of patients after lung resection and one‐lung ventilation (OLV). The objective of this study was to characterise the effect of lung resection and OLV on proposed biomarkers of lung injury in exhaled breath condensate (EBC) and plasma.

Extracorporeal membrane oxygenation for severe acute respiratory failure in adults: NICE guidance

Extracorporeal membrane oxygenation (ECMO) is a modified form of cardiopulmonary bypass that allows short-term support for potentially reversible severe acute respiratory and/or cardiac failure in critically ill adults and children. There is increasing interest in veno-venous (VV) ECMO for severe acute respiratory failure in adults. The National Institute for Health and Clinical Excellence has recently updated its interventional procedure guidance, which summarises available data on efficacy and safety of this procedure and provides guidance for clinicians wishing to undertake VV ECMO. The authors summarise and reflect on the guidelines and discuss some recent developments in technology and clinical practice of VV ECMO.

Systemic inflammation and oxidative stress post-lung resection: effect of pretreatment with N-acetylcysteine

N‐acetylcysteine has been used to treat a variety of lung diseases, where is it thought to have an antioxidant effect. In a randomized placebo‐controlled double‐blind study, the effect of N‐acetylcysteine on systemic inflammation and oxidative damage was examined in patients undergoing lung resection, a human model of acute lung injury.

Contemporary cardiac surgery for adults with congenital heart disease

Objective Advances in early management of congenital heart disease (CHD) have led to an exponential growth in adults with CHD (ACHD). Many of these patients require cardiac surgery. This study sought to examine outcome and its predictors for ACHD cardiac surgery. Methods This is an observational cohort study of prospectively collected data on 1090 consecutive adult patients with CHD, undergoing 1130 cardiac operations for CHD at the Royal Brompton Hospital between 2002 and 2011. Early mortality was the primary outcome measure. Midterm to longer-term survival, cumulative incidence of reoperation, other interventions and/or new-onset arrhythmia were secondary outcome measures. Predictors of early/total mortality were identified. Results Age at surgery was 35±15 years, 53% male, 52.3% were in New York Heart Association (NYHA) class I, 37.2% in class II and 10.4% in class III/IV. Early mortality was 1.77% with independent predictors NYHA class ≥ III, tricuspid annular plane systolic excursion (TAPSE) <15 mm and female gender. Over a mean follow-up of 2.8±2.6 years, 46 patients died. Baseline predictors of total mortality were NYHA class ≥ III, TAPSE <15 mm and non-elective surgery. The number of sternotomies was not independently associated with neither early nor total mortality. At 10 years, probability of survival was 94%. NYHA class among survivors was significantly improved, compared with baseline. Conclusions Contemporary cardiac surgery for ACHD performed at a single, tertiary reference centre with a multidisciplinary approach is associated with low mortality and improved functional status. Also, our findings emphasise the point that surgery should not be delayed because of reluctance to reoperate only.

Association of haemodynamic changes measured by serial central venous saturation during ultrafiltration for acutely decompensated heart failure with diuretic resistance and change in renal function

BACKGROUND Patients with acute decompensated heart failure with diuretic resistance (ADHF-DR) have a poor prognosis. The aim of this study was to assess in patients with ADHF-DR, whether haemodynamic changes during ultrafiltration (UF) are associated with changes in renal function (Δcreatinine) and whether Δcreatinine post UF is associated with mortality. METHODS Seventeen patients with ADHF-DR underwent 20 treatments with UF. Serial bloods (4-6 hourly) from the onset of UF treatment were measured for renal function, electrolytes and central venous saturation (CVO2). Univariate and multivariate analysis were performed to assess the relationship between changes in markers of haemodynamics [heart rate (HR), systolic blood pressure (SBP), packed cell volume (PCV) and CVO2] and Δcreatinine. Patients were followed up and mortality recorded. Cox-regression survival analysis was performed to determine covariates associated with mortality. RESULTS Renal function worsened after UF in 17 of the 20 UF treatments (baseline vs. post UF creatinine: 164±58 vs. 185±69μmol/l, P<0.01). ΔCVO2 was significantly associated with Δcreatinine [β-coefficient of -1.3 95%CI (-1.8 to -0.7), P<0.001] and remained significantly associated with Δcreatinine after considering changes in SBP, HR and PCV [P<0.001]. Ten (59%) patients died at 1-year and 15(88%) by 2-years. Δcreatinine was independently associated with mortality (adjusted-hazard ratio 1.03 (1.01 to 1.07) per 1μmol/l increase in creatinine; P=0.02). CONCLUSIONS Haemodynamic changes during UF as measured by the surrogate of cardiac output was associated with Δcreatinine. Worsening renal function at end of UF treatment occurred in the majority of patients and was associated with mortality.