Management of Metabolic Acidosis in the Post-Cardiac Surgical Patient

From Crossref journal articles via Jisc Publications RouterHistory: epub 2020-10-07, ppub 2020-10-07, issued 2020-10-07Article version: VoRPublication status: PublishedThe base deficit is the best way to evaluate severity of Metabolic Acidosis (MA). It indicates a value corresponding to the number of mmol/L below 24 of the measured bicarbonate concentration. Base deficit between 0 and 5 mmol/L indicates that the patient is not at risk of immediate harm. Arterial blood gases are typically measured every 2-4 hours following cardiac surgery and there is always a trend in base deficit changes to consider. Where the base deficit is diminishing, this indicates that the patient is improving, whereas when it is worsening, the opposite is true. Base deficits between 5 and 10 indicate that a serious problem is present which requires urgent correction. Where the base deficit is greater than 10, cardiac arrest may occur, and such patients require constant supervision by a doctor if active management is being pursued. Where the base deficit is persistently greater than 15, survival is extremely unlikely. This degree of acidosis is associated with widespread disruption of mitochondria at cellular level. The mitochondria often do not recover even if the precipitating cause of the MA is corrected, in which case the patient develops fatal multisystem organ failure. The management of MA in post-cardiac surgical patients is indivisibly bound up in optimizing circulatory physiology. We have not expounded on how this foundational knowledge should be applied but without it the management of MA in this patient population will be severely hampered.pubpu

An endogenous inhibitor of angiogenesis downregulated by hypoxia in human aortic valve stenosis promotes disease pathogenesis

Acknowledgements The authors would like to acknowledge the NHS Grampian Biorepository for their support and assistance with all immunohistochemistry. Sources of funding This work was generously funded by the British Heart Foundation, UK (FS/17/28/32807) and Grampian NHS Endowments.Peer reviewedPublisher PD

Preoperative neutrophil-lymphocyte ratio and outcome from coronary artery bypass grafting

Background: An elevated preoperative white blood cell count has been associated with a worse outcome after coronary artery bypass grafting (CABG). Leukocyte subtypes, and particularly the neutrophil-lymphocyte (N/L) ratio, may however, convey superior prognostic information. We hypothesized that the N/L ratio would predict the outcome of patients undergoing surgical revascularization. Methods: Baseline clinical details were obtained prospectively in 1938 patients undergoing CABG. The differential leukocyte was measured before surgery, and patients were followed-up 3.6 years later. The primary end point was all-cause mortality. Results: The preoperative N/L ratio was a powerful univariable predictor of mortality (hazard ratio [HR] 1.13 per unit, P 3.36). Conclusion: An elevated N/L ratio is associated with a poorer survival after CABG. This prognostic utility is independent of other recognized risk factors.Peer reviewedAuthor versio

Novel immunostimulatory effects of osteoclasts and macrophages on human γδ T cells

25/10/2014 Acknowledgments The authors would like to acknowledge the Oliver Bird Foundation (RHE/00092/S1 24105) (A.P.) and Arthritis Research UK (18439) (K.T.) for funding this work, and to thank Dr Heather M. Wilson for the helpful comments on the manuscript.Peer reviewedPublisher PD

Uric acid levels and outcome from coronary artery bypass grafting

ObjectiveElevated uric acid levels have been associated with an adverse cardiovascular outcome in several settings. Their utility in patients undergoing surgical revascularization has not, however, been assessed. We hypothesized that serum uric acid levels would predict the outcome of patients undergoing coronary artery bypass grafting.MethodsThe study cohort consisted of 1140 consecutive patients undergoing nonemergency coronary artery bypass grafting. Clinical details were obtained prospectively, and serum uric acid was measured a median of 1 day before surgery. The primary end point was all-cause mortality.ResultsDuring a median of 4.5 years, 126 patients (11%) died. Mean (± standard deviation) uric acid levels were 390 ± 131 μmol/L in patients who died versus 353 ± 86 μmol/L among survivors (hazard ratio 1.48 per 100 μmol/L; 95% confidence interval, 1.25–1.74; P < .001). The excess risk associated with an elevated uric acid was particularly evident among patients in the upper quartile (≥410 μmol/L; hazard ratio vs all other quartiles combined 2.18; 95% confidence interval, 1.53–3.11; P < .001). After adjusting for other potential prognostic variables, including the European System for Cardiac Operative Risk Evaluation, uric acid remained predictive of outcome.ConclusionIncreasing levels of uric acid are associated with poorer survival after coronary artery bypass grafting. Their prognostic utility is independent of other recognized risk factors, including the European System for Cardiac Operative Risk Evaluation

A 20-year multicentre outcome analysis of salvage mechanical circulatory support for refractory cardiogenic shock after cardiac surgery

Abstract Background Refractory post-cardiotomy cardiogenic shock (PCCS) is a relatively rare phenomenon that can lead to rapid multi-organ dysfunction syndrome and is almost invariably fatal without advanced mechanical circulatory support (AMCS), namely extra-corporeal membrane oxygenation (ECMO) or ventricular assist devices (VAD). In this multicentre observational study we retrospectively analyzed the outcomes of salvage venoarterial ECMO (VA ECMO) and VAD for refractory PCCS in the 3 adult cardiothoracic surgery centres in Scotland over a 20-year period. Methods The data was obtained through the Edinburgh, Glasgow and Aberdeen cardiac surgery databases. Our inclusion criteria included any adult patient from April 1995 to April 2015 who had received salvage VA ECMO or VAD for PCCS refractory to intra-aortic balloon pump (IABP) and maximal inotropic support following adult cardiac surgery. Results A total of 27 patients met the inclusion criteria. Age range was 34–83 years (median 51 years). There was a large male predominance (n = 23, 85 %). Overall 23 patients (85 %) received VA ECMO of which 14 (61 %) had central ECMO and 9 (39 %) had peripheral ECMO. Four patients (15 %) were treated with short-term VAD (BiVAD = 1, RVAD = 1 and LVAD = 2). The most common procedure-related complication was major haemorrhage (n = 10). Renal failure requiring renal replacement therapy (n = 7), fatal stroke (n = 5), septic shock (n = 2), and a pseudo-aneurysm at the femoral artery cannulation site (n = 1) were also observed. Overall survival to hospital discharge was 40.7 %. All survivors were NYHA class I-II at 12 months’ follow-up. Conclusion AMCS for refractory PCCS carries a survival benefit and achieves acceptable functional recovery despite a significant complication rate