The Risk of Perioperative Bleeding in Patients With Chronic Kidney Disease: A Systematic Review and Meta-Analysis

Kidney disease in trials of perioperative tranexamic acid

STUDY OBJECTIVE

To assess how kidney disease is handled in randomized trials evaluating the safety and efficacy of perioperative tranexamic acid, and to evaluate its effects across levels of kidney function.

DESIGN

Systematic review and meta-analysis of randomized controlled trials.

SETTING

We screened studies from a previous comprehensive systematic review, and updated its search of PubMed, Embase, and Cochrane CENTRAL to July 31, 2023.

PATIENTS

Patients undergoing non-obstetric surgery.

INTERVENTIONS

Intravenous tranexamic acid compared to placebo or usual care without tranexamic acid.

MEASUREMENT

We summarized the handling of kidney disease in eligibility criteria, dose adjustments for kidney function, and effects of tranexamic acid on thrombotic events, seizures, and bleeding by subgroups of kidney function.

MAIN RESULTS

We evaluated 300 trials with 53,085 participants; 45,958 participants (86.6%) were enrolled in 228 trials (76.0%) that explicitly excluded patients with kidney disease. Definitions of kidney diseased used for exclusion varied widely. Most were non-specific and some corresponded to mild disease. Only 5 trials adjusted dosing for kidney function. Meta-analysis of two large trials found tranexamic acid unlikely to substantially increase or decrease the occurrence of thrombotic events in patients with eGFR <60 mL/min/1.73m2 (RR, 0.95; 95% CI: 0.83 to 1.07) or ≥ 60 mL/min/1.73m2 (RR, 1.00; 95% CI, 0.91 to 1.11; P for subgroup difference = 0.47), but both trials excluded patients with severe kidney disease. No analysis could be performed regarding seizure risk. One large trial in noncardiac surgery reported similar reduction in bleeding across subgroups of kidney function but excluded patients with creatinine clearance <30 mL/min.

CONCLUSIONS

The large evidence base supporting perioperative tranexamic acid suffers from broad and unjustified exclusion of patients with kidney disease. Typical perioperative dosing of tranexamic acid is likely safe and effective in patients with creatinine clearance >30 mL/min, but effects in more severe kidney disease are unknown.

Desmopressin to reduce periprocedural bleeding and transfusion: a systematic review and meta-analysis

We systematically reviewed the literature to investigate the effects of peri-procedural desmopressin in patients without known inherited bleeding disorders undergoing surgery or other invasive procedures. We included 63 randomized trials (4163 participants) published up to February 1, 2023. Seven trials were published after a 2017 Cochrane systematic review on this topic. There were 38 trials in cardiac surgery, 22 in noncardiac surgery, and 3 in non-surgical procedures. Meta-analyses demonstrated that desmopressin likely does not reduce the risk of receiving a red blood cell transfusion (25 trials, risk ratio [RR] 0.95, 95% confidence interval [CI] 0.86 to 1.05) and may not reduce the risk of reoperation due to bleeding (22 trials, RR 0.75, 95% CI 0.47 to 1.19) when compared to placebo or usual care. However, we demonstrated significant reductions in number of units of red blood cells transfused (25 trials, mean difference -0.55 units, 95% CI - 0.94 to - 0.15), total volume of blood loss (33 trials, standardized mean difference - 0.40 standard deviations; 95% CI - 0.56 to - 0.23), and the risk of bleeding events (2 trials, RR 0.45, 95% CI 0.24 to 0.84). The certainty of evidence of these findings was generally low. Desmopressin increased the risk of clinically significant hypotension that required intervention (19 trials, RR 2.15, 95% CI 1.36 to 3.41). Limited evidence suggests that tranexamic acid is more effective than desmopressin in reducing transfusion risk (3 trials, RR 2.38 favoring tranexamic acid, 95% CI 1.06 to 5.39) and total volume of blood loss (3 trials, mean difference 391.7 mL favoring tranexamic acid, 95% CI - 93.3 to 876.7 mL). No trials directly informed the safety and hemostatic efficacy of desmopressin in advanced kidney disease. In conclusion, desmopressin likely reduces periprocedural blood loss and the number of units of blood transfused in small trials with methodologic limitations. However, the risk of hypotension needs to be mitigated. Large trials should evaluate desmopressin alongside tranexamic acid and enroll patients with advanced kidney disease.

A systematic review of right atrial bypass grafting in the management of central venous occlusive disease in patients undergoing hemodialysis

INTRODUCTION

Central venous occlusive disease (CVOD) is a complication that can occur in patients with end-stage renal disease who are receiving hemodialysis. When CVOD develops, patients often require multiple re-interventions to maintain their dialysis access. CVOD can be treated by various strategies such as balloon angioplasty, stenting, lower limb or extra-anatomical grafts, hybrid grafts or surgical bypasses such as right atrial (RA). In this systematic review, we aim to evaluate the indications, technical aspects, and outcomes after RA bypass grafting for the treatment of CVOD in hemodialysis patients.

METHODS

A systematic and comprehensive literature search was conducted using various electronic databases. We included articles that reported described and reported outcomes of RA bypass grafting for the treatment of CVOD in hemodialysis patients. A narrative review of the indications and technical aspects of RA bypass grafting was performed. We also pooled and reported the primary patency, secondary patency, postoperative complications, and 30-day mortality of RA bypass grafting.

RESULTS

A total of 21 studies with 55 patients who underwent RA bypass grafting were included in our systematic review. Follow-up period ranged from 0.5 to 84 months. The mean pooled primary patency and secondary patency of RA bypass grafting were 8.1 ± 4.9 and 21.7 ± 20.1 months, respectively. The incidence of early postoperative complications such as surgical site infection, bleeding, and access thrombosis was 0%, 4%, and 4%, respectively. The overall 30-day mortality was 4%.

CONCLUSIONS

This systematic review summarizes the patient characteristics, technical features and outcomes of RA bypass grafting in the treatment of hemodialysis-related CVOD. RA bypass grafting may be a viable last-resort option when less invasive or conventional treatment options have been exhausted.

Glomerular hyperfiltration is an independent predictor of postoperative outcomes: A NSQIP multi-specialty surgical cohort analysis

AIM

While high estimated glomerular filtration rate (eGFR) has been associated with increased overall mortality, its effect on postoperative outcomes is relatively understudied. We sought to investigate the association between high eGFR and 30-day postoperative outcomes using a multi-specialty surgical cohort.

METHODS

Using the National Surgical Quality Improvement Program database, we selected adult for whom eGFR could be calculated using the 2021 Chronic Kidney Disease Epidemiology Collaboration equation. Based on sex-specific distributions of eGFR stratified by age quintiles, we classified patients into low (<5th percentile), normal (5-95th percentile) and high eGFR (>95th percentile). The primary outcome was a composite of any 30-day major adverse outcomes, including: death, reoperation, cardiac arrest, myocardial infarction and stroke. Secondary outcomes included 30-day infectious complications, venous thromboembolism (VTE), bleeding requiring transfusion, prolonged length of stay and unplanned readmission. After matching for demographic differences, comorbidity burden and operative characteristics, logistic regression models were used to evaluate the association between extremes of eGFR and the outcomes of interest.

RESULTS

Of 1 668 447 patients, 84 115 (5.07%) had a high eGFR. High eGFR was not associated with major adverse outcomes (odds ratio [OR] 1.00 [95% confidence interval (CI): 0.97, 1.03]); however, it was associated with reoperation (OR 1.04 [95% CI: 1.00,1.08]), infectious complications (OR 1.14 [95% CI: 1.11, 1.16]), VTE (OR 1.15 [95% CI: 1.09, 1.22]) and prolonged length of stay (OR 1.19 [95% CI: 1.16, 1.21]).

CONCLUSION

Our findings support an association between high eGFR and adverse 30-day postoperative outcomes.

Preoperative renal insufficiency predicts postoperative adverse outcomes in a mixed surgical population: a retrospective matched cohort study using the NSQIP database

BACKGROUND

The incidence of chronic kidney disease is increasing, but most cases are not diagnosed until the accidental finding of abnormal laboratory data or the presentation of severe symptoms. Patients with chronic kidney disease are reported to have an increased risk of postoperative mortality and morbidities, but previous studies mainly targeted populations undergoing cardiovascular surgery. The authors aimed to evaluate the risk of postoperative mortality and complications in a surgical population with preoperative renal insufficiency (RI).

MATERIALS AND METHODS

This retrospective cohort study used data from the National Surgical Quality Improvement Program database between 2013 and 2018 to evaluate the risk of postoperative morbidity and mortality in the surgical population. Patients with estimated glomerular filtration rate less than 60 ml/min/1.73 m 2 were defined as the RI group. Propensity score matching methods and multivariate logistic regression were used to calculate the risk of postoperative morbidity and mortality.

RESULTS

After propensity score matching, 502 281 patients were included in the RI and non-RI groups. The RI group had a higher risk of 30-day in-hospital mortality (odds ratio: 1.54, 95% CI: 1.49-1.58) than the non-RI group. The RI group was associated with a higher risk of postoperative complications, including myocardial infarction, stroke, pneumonia, septic shock, and postoperative bleeding. The RI group was also associated with an increased risk of prolonged ventilator use for over 48 h, readmission, and reoperation.

CONCLUSION

Patients with preoperative RI have an increased risk of postoperative 30-day mortality and complications. RI group patients with current dialysis, estimated glomerular filtration rate less than or equal to 30 ml/min/1.73 m 2 or concomitant anemia had an elevated risk of postoperative mortality.

Hip hemiarthroplasty for the treatment of femoral neck fractures in dialysis patients

OBJECTIVES

This study sought to delineate the postoperative outcomes in dialysis patients undergoing hip hemiarthroplasty (HHA) for the treatment of femoral neck fractures (FNF) in order to better optimise pre- and postoperative management and minimise short-term morbidity and mortality rates.

METHODS

16,955 patients who had undergone HHA for femoral neck fractures from 2005 to 2018 were isolated from a multi-institutional surgical registry, of which 343 (2.0%) were on dialysis and 16,612 (98.0%) were not. The cohorts were identified/analysed for differences in their comorbidities, demographic factors, and 30-day postoperative complications using Fischer's exact tests and Mann-Whitney U-tests. Coarsened exact matching (CEM) was implemented in order to control for baseline difference in demographics and comorbidities. Multivariate logistic regression analyses were used to assess the impact of dialysis as an independent risk factor for various complications, including reoperations, readmissions, and mortality.

RESULTS

Upon CEM-matching (L1-statistic <0.001), weighted multivariate logistic regression analyses demonstrated dialysis to be an independent risk factor for minor complications (OR 3.051, p < 0.001), pneumonia (OR 3.943, p < 0.001), urinary tract infections (UTIs) (OR 2.684, p < 0.001), major complications (OR 1.892, p < 0.001), unplanned intubation (OR 2.555, p = 0.047), cardiac arrest (OR 11.897, p < 0.001), deep vein thrombosis (DVT), (OR 2.610, p = 0.049), and mortality (OR 2.960, p < 0.001).

CONCLUSIONS

Dialysis independently increased the risk for unplanned intubation, cardiac arrest, blood transfusions, pneumonia, DVT, and mortality. In communicating postoperative expectations, surgeons should aim to clarify the patients' preferences and potential resuscitation designations prior to surgical intervention due to the increased risk of serious complications. A lower threshold of suspicion for DVT in this population is reasonable. Identifying high-risk patient populations that may experience increased rates of complications, with the ensuing financial expenditures, due to medical complexity rather than subpar management may help providers avoid penalties in caring for these patients.

A 5-year propensity-matched analysis of perioperative outcomes in patients with chronic kidney disease undergoing bariatric surgery

BACKGROUND

Bariatric surgery can improve renal function in patients with comorbid chronic kidney disease (CKD) and obesity. Additionally, bariatric surgery can enhance outcomes following renal transplantation. The safety of bariatric surgery in patients with CKD has been debated in the literature. This study evaluates the frequency of perioperative complications associated with CKD.

METHODS

The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database was queried from 2015-2019. Patients were included if they had a vertical sleeve gastrectomy (VSG) or Roux-en-Y gastric bypass (RYGB) and were stratified based on CKD status. An unmatched and propensity-matched analysis was performed comparing 30-day perioperative outcomes between the groups.

RESULTS

A total of 717,809 patients included in this study, 5817(0.8%) had CKD, of whom 2266(0.3%) were on dialysis. 74.3% of patients with CKD underwent VSG with 25.7% underwent RYGB. Comparing RYGB to VSG, patients who underwent RYGB had a higher rate of deep organ space infection (0.7%vs.0.1%,p = 0.021) and re-intervention (5.0% vs. 2.2%,p < 0.001). Within the VSG cohort, a matched analysis was performed for those with CKD and without CKD. The CKD cohort had higher risk of complications such as bleeding (2.1%vs. 0.9%,p < 0.001), readmission (9.3%vs.4.9%,p < 0.001), reoperation (2.7%vs.1.3%,p < 0.001), and need for reintervention (2.2%vs.1.3%,p < 0.001). Notably, patients with CKD also had a higher mortality (0.6%vs.0.2%,p = 0.003). No difference was seen between patients with renal insufficiency and patients on dialysis.

CONCLUSION

VSG has been the operation of choice in patients with CKD. Our results showed it is the safer option for patients with CKD compared to RYGB. Although this patient population does have an increased risk of adverse perioperative events, dialysis didn't affect the outcome. Bariatric surgeons who operate on patients with CKD should be well informed and remain vigilant given the increased perioperative risk. The risk is still considerably low, and the potential benefit on renal function and improvement in candidacy for renal transplant outweigh the risk. They should be considered as surgical candidates.

Preoperative Evaluation and Management of Patients With Select Chronic Gastrointestinal, Liver, and Renal Diseases

Patients with chronic gastrointestinal, hepatic, and renal disease are frequently encountered in clinical practice. This is due in part to the rising prevalence of risk factors associated with these conditions. These patients are increasingly being considered for surgical intervention and are at higher risk for multiple perioperative complications. Many are able to safely undergo surgery but require unique considerations to ensure optimal perioperative care. In this review, we highlight relevant perioperative physiology and outline our approach to the evaluation and management of patients with select chronic gastrointestinal, hepatic, and renal diseases. A comprehensive preoperative evaluation with a multidisciplinary approach is often beneficial, and specialist involvement should be considered. Intraoperative and postoperative plans should be individualized based on the unique medical and surgical characteristics of each patient.

Repurposing drugs for highly prevalent diseases: pentoxifylline, an old drug and a new opportunity for diabetic kidney disease

Diabetic kidney disease is one of the most frequent complications in patients with diabetes and constitutes a major cause of end-stage kidney disease. The prevalence of diabetic kidney disease continues to increase as a result of the growing epidemic of diabetes and obesity. Therefore, there is mounting urgency to design and optimize novel strategies and drugs that delay the progression of this pathology and contain this trend. The new approaches should go beyond the current therapy focussed on the control of traditional risk factors such as hyperglycaemia and hypertension. In this scenario, drug repurposing constitutes an economic and feasible approach based on the discovery of useful activities for old drugs. Pentoxifylline is a nonselective phosphodiesterase inhibitor currently indicated for peripheral artery disease. Clinical trials and meta-analyses have shown renoprotection secondary to anti-inflammatory and antifibrotic effects in diabetic patients treated with this old known drug, which makes pentoxifylline a candidate for repurposing in diabetic kidney disease.

Is Chronic Kidney Disease Affecting the Postoperative Complications of Vitrectomy for Proliferative Diabetic Retinopathy?

Chronic kidney disease (CKD) is a well-known risk factor for postoperative complications in several surgical fields. However, although prevalent among diabetic candidates for vitrectomy, the effect of CKD on vitrectomy outcomes remains unclear. This study aimed at clarifying the relationship between CKD and the occurrence of vitrectomy-related complications in patients with proliferative diabetic retinopathy (PDR). The 6-month incidences of vitreous hemorrhage (VH) and neovascular glaucoma (NVG) following vitrectomy for PDR were compared among the following groups: stages 1–2 CKD (60 patients), stages 3–5 CKD (70 patients not on hemodialysis), and hemodialysis (HD; 30 patients). We also determined whether the deterioration of the estimated glomerular filtration rate (eGFR) was associated with post-vitrectomy events. The incidence of VH was significantly higher in the stages 3–5 CKD group (43%) than in the stages 1–2 CKD (10%) and HD (10%) groups. NVG was more common in the stages 3–5 CKD group (17%) than in the stages 1–2 CKD (2%) and HD (0%) groups. The reduced estimated glomerular filtration rate (eGFR) was the only significant variable associated with post-vitrectomy VH and NVG. Patients with PDR and CKD, particularly those with lower eGFR, might be at risk for post-vitrectomy VH and NVG.

Use of Sertraline in Hemodialysis Patients

Depression and anxiety are the most common psychiatric disorders in end-stage renal disease (ESRD) patients treated with hemodialysis (HD) and may correlate with lower quality of life and increased mortality. Depression treatment in HD patients is still a challenge both for nephrologists and psychiatrists. The possible treatment of depressive disorders can be pharmacological and non-pharmacological. In our article, we focus on the use of sertraline, the medication which seems to be relatively safe and efficient in the abovementioned population, taking under consideration several limitations regarding the use of other selective serotonin reuptake inhibitors (SSRIs). In our paper, we discuss different aspects of sertraline use, taking into consideration possible benefits and side effects of drug administration like impact on QTc (corrected QT interval) prolongation, intradialytic hypotension (IDH), chronic kidney disease-associated pruritus (CKD-aP), bleeding, sexual functions, inflammation, or fracture risk. Before administering the medication, one should consider benefits and possible side effects, which are particularly significant in the treatment of ESRD patients; this could help to optimize clinical outcomes. Sertraline seems to be safe in the HD population when provided in proper doses. However, we still need more studies in this field since the ones performed so far were usually based on small samples and lacked placebo control.

The Perioperative Surgical Home, Enhanced Recovery After Surgery and how integration of these models may improve care for medically complex patients

Perioperative medicine is changing rapidly, and with this change comes the opportunity to improve upon current models of care delivery and integration within the health care system. Perioperative models of care are structured or conceptual arrangements for surgical patients before, during and after their surgery. Models of care such as the Perioperative Surgical Home and Enhanced Recovery After Surgery pathways are increasingly used to guide the structure of perioperative care delivery with an aim to improve patient outcomes and experience in Canadian settings. In this narrative review, we summarize the origins of these perioperative models of care. They are fundamentally different in scope and level of evidence. Both models have potential benefits and limitations to their broad implementation in our health care system. As currently developed, both models are limited in their application to patients with chronic disease. We discuss how these models of care can be used to develop integrated horizontal and vertical perioperative pathways in a Canadian setting. Such integration is a potential solution that will improve their applicability to patients with medically complex conditions and in times when health care systems are under pressure. We describe this approach using the example of patients with kidney failure receiving dialysis.

The risk of major bleeding event in patients with chronic kidney disease on pentoxifylline treatment

Patients with chronic kidney diseases (CKD) are often treated with antiplatelets due to aberrant haemostasis. This study aimed to evaluate the bleeding risk with CKD patients undergoing pentoxifylline (PTX) treatment with/without aspirin. In this retrospective study, we used Taiwan’s National Health Insurance Research Database to identify PTX treated CKD patients. Patients undergoing PTX treatment after CKD diagnosis were PTX group. A 1:4 age, sex and aspirin used condition matched CKD patients non-using PTX were identified as controls. The outcome was major bleeding event (MBE: intracranial haemorrhage (ICH) and gastrointestinal tract bleeding) during 2-year follow-up period. Risk factors were estimated using Cox regression for overall and stratified analysis. The PTX group had higher MBE risk than controls (hazard ratio (HR) 1.19; 95% confidence interval (CI) 0.94–1.50). In stratified analysis, hyperlipidaemia was a significant risk factor (HR: 1.42; 95% CI 1.01–2.01) of MBE. A daily PTX dose larger than 800 mg, females, non-regular aspirin usage, and ischaemic stroke were risk factors for MBE in PTX group. When prescribing PTX in CKD patients, bleeding should be closely monitored, especially in those with daily dose more than 800 mg, aspirin users, and with a history of ischaemic stroke.

Autologous Blood Donation Before Hepatectomy in Patients With Chronic Kidney Disease

Autologous blood is sometimes collected before hepatectomy. The usefulness of autologous blood donation (ABD) has been reported in several studies. However, the relationship between ABD and CKD has never been studied. The aim of this study was to clarify the relationship between preoperative autologous blood donation (ABD) and chronic kidney disease (CKD) in anemia. Between January 2006 and December 2012, 70 patients made 2 ABDs ≥ 600 mL before hepatectomy. CKD stages were based on estimated glomerular filtration rates. Univariate analyses were performed using the Mann–Whitney U test for continuous variables and the chi-square test for nominal variables. Patients at CKD stages &lt; G3b (n = 60) and ≥ G3b (n = 10) were compared. There were no significant differences in hemoglobin level at the initial hospital visit or total volume of ABD between the 2 groups. However, hemoglobin levels just before the first ABD, the second ABD, and resection, and just after resection were significantly lower in the CKD ≥ G3b group than those in the &lt; G3b group (P &lt; 0.05). CKD stage contributes to reductions in hemoglobin levels after ABD. We recommend the use of erythropoietin in CKD ≥ G3b cases that include ABDs.

Terminal Phase Components of the Clotting Cascade in Patients with End-Stage Renal Disease Undergoing Hemodiafiltration or Hemodialysis Treatment

Hemostasis disorder in patients with end-stage renal disease (ESRD) is frequently associated with bleeding diathesis but it may also manifest in thrombotic complications. Analysis of individual coagulation and fibrinolytic factors may shed light on the background of this paradox situation. Here we explored components essential for fibrin formation/stabilization in ESRD patients being on maintenance hemodiafiltration (HDF) or hemodialysis (HD). Pre-dialysis fibrinogen, factor XIII (FXIII) antigen concentrations and FXIII activity were elevated, while α₂-plasmin inhibitor (α₂PI) activity decreased. The inflammatory status, as characterized by C-reactive protein (CRP) was a key determinant of fibrinogen concentration, but not of FXIII and α₂PI levels. During a 4-h course of HDF or HD, fibrinogen concentration and FXIII levels gradually elevated. When compensated for the change in plasma water, i.e., normalized for plasma albumin concentration, only FXIII elevation remained significant. There was no difference between HDF and HD treatments. Individual HDF treatment did not influence α₂PI activity, however after normalization it decreased significantly. HD treatment had a different effect, α₂PI activities became elevated but the elevation disappeared after normalization. Elevated fibrinogen and FXIII levels in ESRD patients might contribute to the increased thrombosis risk, while decreased α₂PI activity might be associated with elevated fibrinolytic potential.

Genetic Polymorphisms and Perioperative Bleeding in Off-Pump Coronary Artery Bypass Grafting Surgery

BACKGROUND

Clopidogrel use before coronary artery bypass graft surgery may increase risk for perioperative hemorrhage. The effect of genetic polymorphisms related to clopidogrel responses on bleeding during or after off-pump coronary artery bypass graft surgery is unknown.

METHODS

This prospective study included 206 coronary artery disease patients scheduled for off-pump coronary artery bypass graft surgery. Genotypes were determined using Sequenom MassARRAY system. Severe bleeding was defined by the universal definition of perioperative bleeding in cardiac surgery.

RESULTS

Patients carrying the ABCB1 3435 wild-type genotype (CC) had a higher risk of severe perioperative bleeding compared with patients carrying the variant genotype (CT or TT; 33.9% vs 16.5%, P = .009). Low baseline hemoglobin level (odds ratio 0.944; 95% confidence interval, 0.917 to 0.972; P < .001), low baseline estimated glomerular filtration rate (odds ratio 0.977; 95% confidence interval, 0.956 to 0.999; P = .041), discontinuing clopidogrel 5 days or less before surgery (odds ratio 2.458; 95% confidence interval, 1.044 to 5.786; P = .039), and the ABCB1 wild-type genotype (CC; odds ratio 2.941; 95% confidence interval, 1.250 to 6.944; P = .014) were independent risk factors for severe perioperative bleeding.

CONCLUSIONS

Patients carrying the ABCB1 wild-type genotype (CC) had a higher rate of severe perioperative bleeding compared with patients carrying the variant genotype (CT or TT). Discontinuation of clopidogrel 5 days or less before surgery and the ABCB1 wild-type genotype (CC) were independent risk factors for severe perioperative bleeding.

Non-cardiac surgery in patients with coronary artery disease: risk evaluation and periprocedural management

Perioperative cardiovascular complications are important causes of morbidity and mortality associated with non-cardiac surgery, particularly in patients with coronary artery disease (CAD). Although preoperative cardiac risk assessment can facilitate the identification of vulnerable patients and implementation of adequate preventive measures, excessive evaluation might lead to undue resource utilization and surgical delay. Owing to conflicting data, there remains some uncertainty regarding the most beneficial perioperative strategy for patients with CAD. Antithrombotic agents are the cornerstone of secondary prevention of ischaemic events but substantially increase the risk of bleeding. Given that 5-25% of patients undergoing coronary stent implantation require non-cardiac surgery within 2 years, surgery is the most common reason for premature cessation of dual antiplatelet therapy. Perioperative management of antiplatelet therapy, which necessitates concomitant evaluation of the individual thrombotic and bleeding risks related to both clinical and procedural factors, poses a recurring dilemma in clinical practice. Current guidelines do not provide detailed recommendations on this topic, and the optimal approach in these patients is yet to be determined. This Review summarizes the current data guiding preoperative risk stratification as well as periprocedural management of patients with CAD undergoing non-cardiac surgery, including those treated with stents.

Bleeding Independently associated with Mortality after noncardiac Surgery (BIMS): an international prospective cohort study establishing diagnostic criteria and prognostic importance

BACKGROUND

We aimed to establish diagnostic criteria for bleeding independently associated with mortality after noncardiac surgery (BIMS) defined as bleeding during or within 30 days after noncardiac surgery that is independently associated with mortality within 30 days of surgery, and to estimate the proportion of 30-day postoperative mortality potentially attributable to BIMS.

METHODS

This was a prospective cohort study of participants ≥45 yr old having inpatient noncardiac surgery at 12 academic hospitals in eight countries between 2007 and 2011. Cox proportional hazards models evaluated the adjusted relationship between candidate diagnostic criteria for BIMS and all-cause mortality within 30 days of surgery.

RESULTS

Of 16 079 participants, 2.0% (315) died and 36.1% (5810) met predefined screening criteria for bleeding. Based on independent association with 30-day mortality, BIMS was identified as bleeding leading to a postoperative haemoglobin <70 g L^-1, transfusion of ≥1 unit of red blood cells, or that was judged to be the cause of death. Bleeding independently associated with mortality after noncardiac surgery occurred in 17.3% of patients (2782). Death occurred in 5.8% of patients with BIMS (161/2782), 1.3% (39/3028) who met bleeding screening criteria but not BIMS criteria, and 1.1% (115/10 269) without bleeding. BIMS was associated with mortality (adjusted hazard ratio: 1.87; 95% confidence interval: 1.42-2.47). We estimated the proportion of 30-day postoperative deaths potentially attributable to BIMS to be 20.1-31.9%.

CONCLUSIONS

Bleeding independently associated with mortality after noncardiac surgery (BIMS), defined as bleeding that leads to a postoperative haemoglobin <70 g L^-1, blood transfusion, or that is judged to be the cause of death, is common and may account for a quarter of deaths after noncardiac surgery.

CLINICAL TRIAL REGISTRATION

NCT00512109.

Operative Versus Nonoperative Management of Hemorrhage in the Postoperative Kidney Transplant Patient

BACKGROUND

Postoperative hemorrhage has been described at rates of 14% in kidney transplant (KT) literature. The preferred management of postoperative hemorrhage in this population is not well described. We hypothesized a difference in outcomes with operative versus nonoperative management of hemorrhage after kidney transplantation.

METHODS

We conducted a retrospective cohort study of consecutive KTs from 2012 to 2019 (living and deceased donors). We defined hemorrhage based on the objective finding of hematoma on either ultrasound or CT scan. Management was defined as operative (surgical intervention with or without transfusion) or nonoperative (with or without transfusion).

RESULTS

We performed 1758 KTs of which 135 (8%) demonstrated hematoma on ultrasound or CT scan (66 operative vs 69 nonoperative management). The clinical signs and symptoms of low urine output (P = .044), drop in hemoglobin (P < .001), abdominal pain (P = .005), and MAP < 70 mm Hg (P = .034) were 92.5% predictive of postoperative hemorrhage in our KT patients. There were no differences between groups based on medical history, preop anticoagulation, anastomosis type, cold ischemic time, lowest hemoglobin, delayed graft function, or complications. Patients with nonoperative treatment of postoperative hemorrhage had shorter lengths of stay (P = .003), better graft survival (P = .01), and better patient survival (P = .01).

DISCUSSION

We found better outcomes of graft and patient survival with shorter lengths of stay when we utilized nonoperative management of postoperative hemorrhage in KT patients. Our findings suggest a role for conservative nonoperative management in select patients. Ultimately, it is the surgeon's choice on how best to manage postoperative hemorrhage.

Anesthetic Considerations for Patients on Renal Replacement Therapy

The number of patients presenting for surgery with renal dysfunction requiring renal replacement therapy (RRT) is expected to increase as the population ages and improvements in therapy continue to be made. Every aspect of the perioperative period is affected by renal dysfunction, its associated comorbidities, and altered physiology secondary to RRT. Most alarming is the increased risk for perioperative cardiac morbidity and mortality seen in this population. Perioperative optimization and management aims to minimize these risks; however, few definite guidelines on how to do so exist.

Assessment of long term outcomes after buccal mucosal graft urethroplasty: the impact of chronic kidney disease

Objectives

To compare and assess various outcomes and success of buccal mucosal graft urethroplasty (BMGU) in patients with CKD versus patients having normal renal function.

Material and Methods

This was a retrospective, single centre study, during period 2013 to 2017. Patients were grouped into two groups. Group 1 had patients with estimated Glomerular Filtration Rate (eGFR)>60mL/min/1.73m2 while group 2 had patients with eGFR <60mL/min/1.73m². eGFR was calculated according to the MDRD equation. The two groups were compared with regard to various outcomes like length, location of stricture, technique of graft placement, intra-operative blood loss (haemoglobin drop), duration of hospital stay, post-operative complications and recurrence.

Results

A total of 223 patients were included in study with group 1 had 130 patients and group 2 had 93 patients. Mean age of patients with CKD were higher (47.49 years versus 29.13 years). The mean follow-up period was comparable between both groups (23.29 months and 22.54 months respectively). Patients with CKD had more post-operative Clavien Grade 2 or higher complications (p=0.01) and a greater recurrence rates (p<0.001) than in non-CKD patients. On multivariate analysis, age and CKD status was significant predictor of urethroplasty success (p=0.004) (OR= 14.98 (1.952-114.94, 95% CI).

Conclusions

CKD patients are more prone to post-operative complications in terms of wound infection, graft uptake and graft failure and higher recurrence rates following BMGU.

Adverse outcomes after non urological surgeries in patients with chronic kidney disease: a propensity-score-matched study

Objective

To evaluate the complications, mortality, and medical expenditures after nonurological surgical procedures in patients with chronic kidney disease (CKD).

Methods

Using claims data of Taiwan’s National Health Insurance, we conducted a matched cohort study of 35,643 patients with CKD who underwent nonurological surgeries in 2008–2013. By using a propensity-score matching procedure, 35,643 non-CKD patients were selected for comparison. Logistic regression was used to calculate the odds ratios (ORs) and the 95% confidence intervals (CIs) of postoperative complications and in-hospital mortality associated with CKD.

Results

The results showed that patients with CKD had higher risks of postoperative septicemia (OR: 1.78, 95% CI: 1.68–1.89), pneumonia (OR: 1.60, 95% CI: 1.48–1.73), stroke (OR: 1.34, 95% CI: 1.24–1.44), and in-hospital mortality (OR: 2.17, 95% CI: 1.90–2.47) compared with non-CKD patients. Longer hospital stays and higher medical expenditures after nonurological surgical procedures were noted in CKD patients. The association between CKD and postoperative adverse events was significant in both sexes, all of the age groups, and the other subgroups. Histories of myocardial infarction, epilepsy, and ages greater than 70 years were factors that were significantly associated with postoperative adverse events.

Conclusion

Compared with non-CKD patients, surgical patients with CKD exhibited more adverse events, with risks of in-hospital mortality that were approximately 2-fold higher after nonurinary surgery. These findings suggest an urgent need to revise the protocols for postoperative care in this population.

Evaluation of hemostasis in patients with end-stage renal disease

An increased bleeding risk is reported for patients with end-stage renal disease. This study aims to analyze, whether bleeding risk can be assessed by global tests of hemostasis. Standard laboratory tests and an extended evaluation of hemostasis by rotational thromboelastometry, platelet function analyzer (PFA) and multiple electrode aggregometry as well as thrombin generation assays and measurement of fibrinolytic potential were performed in 20 patients on hemodialysis, 10 patients on peritoneal dialysis, 10 patients with chronic kidney disease stage G5 (CKD5) and in 10 healthy controls (HC). Hemoglobin was significantly lower in patients with end-stage renal disease versus HC (each p<0.01). Patients on peritoneal dialysis showed increased fibrinogen levels compared to HC (p<0.01), which were also reflected by FIBTEM results (each p<0.05). 41% of hemodialysis patients and 44% of CKD5 patients presented with prolonged PFA-ADP-test (p<0.05), while no patient on peritoneal dialysis and no HC offered this modification. Thrombin generating potential was significantly lower in patients on hemodialysis, while clot lysis time revealed a hypofibrinolytic state in patients on hemo- and peritoneal dialysis compared to HC (p<0.001). In conclusion, patients with end-stage renal disease have complex hemostatic changes with both hyper- and hypocoagulable features, which are dependent on use and type of dialysis. Hypercoagulable features include elevated fibrinogen levels and a hypofibrinolytic state, whereas hypocoagulable features include decreased thrombin generating capacity and platelet dysfunction. Our results may contribute to a more rational approach to hemostatic management in these patients.

Safety of Laparoscopic Radical Gastrectomy in Gastric Cancer Patients with End-Stage Renal Disease

Purpose

The surgical outcomes of end-stage renal disease (ESRD) patients undergoing radical gastrectomy for gastric cancer were inferior compared with those of non-ESRD patients. This study aimed to evaluate the short- and long-term surgical outcomes of ESRD patients undergoing laparoscopic gastrectomy (LG) and open gastrectomy (OG) for gastric cancer.

Materials and Methods

Between 2004 and 2014, 38 patients (OG: 21 patients, LG: 17 patients) with ESRD underwent gastrectomy for gastric cancer. Comparisons were made based on the clinicopathological characteristics, surgical outcomes, and long-term survival rates.

Results

No significant differences were noted in the clinicopathological characteristics of either group. LG patients had lower estimated blood loss volumes than OG patients (LG vs. OG: 94 vs. 275 mL, P=0.005). The operation time and postoperative hospital stay were similar in both the groups. The postoperative morbidity for LG and OG patients was 41.1% and 33.3%, respectively (P=0.873). No significant difference was observed in the long-term overall survival rates between the 2 groups (5-year overall survival, LG vs. OG: 82.4% vs. 64.7%, P=0.947).

Conclusions

In ESRD patients, LG yielded non-inferior short- and long-term surgical outcomes compared to OG. Laparoscopic procedures might be safely adopted for ESRD patients who can benefit from the advantages of minimally invasive surgery.

Impaired glucose metabolism is associated with increased thrombin generation potential in patients undergoing angioplasty and stenting

Background

As a strong platelet agonist on the one hand and key molecule in plasmatic coagulation on the other hand, thrombin connects primary and secondary hemostasis. Thrombin generation potential reflects the individual capacity to generate thrombin, and has been associated with the occurrence of thromboembolic events. In the current study, we sought to identify predictors of thrombin generation potential in patients undergoing angioplasty and stenting for atherosclerotic cardiovascular disease.

Methods

Peak thrombin generation potential and area under the curve (AUC) of thrombin generation potential were determined with a commercially available assay in 315 patients on dual antiplatelet therapy 1 day after percutaneous intervention, and in 100 healthy individuals without cardiovascular disease.

Results

Median (interquartile range) peak thrombin generation potential and AUC of thrombin generation potential in the study cohort (n = 315) were significantly higher than in healthy individuals (n = 100) without cardiovascular disease (peak thrombin generation potential: 445.4 nM [354.5–551.8 nM] vs. 174.5 nM [141.2–261.2 nM]; AUC of thrombin generation potential: 5262.7 nM thrombin [4806.6–5756.9 nM thrombin] vs. 3405.2 nM thrombin [3043.6–3747.3 nM thrombin]; both p < 0.001). In patients undergoing angioplasty and stenting, hemoglobin A1c (HbA1c) was the only variable that was independently associated with both, peak thrombin generation potential and AUC of thrombin generation potential (both p ≤ 0.007). In contrast, platelet count and high-sensitivity C-reactive protein were only associated with peak thrombin generation potential, and body mass index and serum creatinine were only associated with AUC of thrombin generation potential after adjustment for covariates by multivariate linear regression analyses (all p < 0.05). Patients with HbA1c ≥ 6% had significantly higher peak thrombin generation potential and AUC of thrombin generation potential than patients with HbA1c < 6% (peak thrombin generation potential: 476.9 nM [385.8–577.9 nM] vs. 423.9 nM [335.8–529.5 nM], p = 0.002; AUC of thrombin generation potential: 5371.8 nM thrombin [4903 – 5899 nM thrombin] vs. 5172.5 nM thrombin [4731.8–5664.7 nM thrombin], p = 0.01). HbA1c ≥ 6% remained independently associated with both parameters of thrombin generation potential after multivariate linear regression analyses (both p ≤ 0.02).

Conclusions

Impaired glucose metabolism is associated with increased thrombin generation potential in patients undergoing angioplasty and stenting for cardiovascular disease.

Gastrointestinal bleeding risk of selective serotonin reuptake inhibitors by level of kidney function: A population-based cohort study

Aim

To estimate the risk of gastrointestinal (GI) bleeding associated with serotonin reuptake inhibitors (SSRIs) by level of kidney function.

Methods

We conducted a cohort study using the Clinical Practice Research Datalink linked to Hospital Episode Statistics. We identified patients with chronic kidney disease (CKD; estimated glomerular filtration rate <60 ml min^–1 1.73 m^–2 for ≥3 months), and a comparison group of patients without it. Patients with CKD were further classified as stage 3a (eGFR 45–59 ml min^–1 1.73 m^–2), 3b (30–44 ml min^–1 1.73 m^–2) and 4/5 (<30 ml min^–1 1.73 m^–2). We excluded prevalent SSRI users at cohort entry. Exposure was time‐dependent SSRI prescription and outcome was first hospitalization for GI bleeding. We estimated adjusted rate ratio (aRR) and rate difference (aRD) of GI bleeding comparing periods with and without SSRI prescription at each level of kidney function.

Results

The aRRs and aRDs were: (i) no CKD (n = 202 121) aRR: 1.66 (95%CI 1.37–2.01), aRD: 2.0/1000 person–years (5.5 vs. 3.5/1000 person–years in period with and without SSRIs); (ii) CKD stage 3a (n = 153 316) aRR: 1.86 (1.62–2.15), aRD: 4.2/1000 person–years (8.3 vs. 4.1/1000 person–years); (iii) CKD stage 3b (n = 46 482) aRR: 1.61 (1.27–2.04), aRD: 4.8/1000 person–years (9.9 vs. 5.1/1000 person–years); and (iv) CKD stage 4/5 (n = 11 197) aRR: 1.84 (1.14–2.96), aRD: 7.9/1000 person–years (15.3 vs. 7.4/1000 person–years). While there was no evidence of increase in the aRR (P = 0.922), there was strong evidence that the aRD increased as kidney function deteriorated (P = 0.001).

Conclusions

While the relative risk was constant, the excess risk of GI bleeding associated with SSRIs markedly increased among patients with decreased kidney function.

Efficacy of Statin Therapy Related to Baseline Renal Function in Patients with Rheumatic Heart Disease Undergoing Cardiac Surgery

Background

Renal impairment increases the risk of cardiovascular events and perioperative complications in patients with heart valve disease. This study aimed to determine the perioperative benefit of statin treatment related to baseline renal function in patients with rheumatic heart disease (RHD) who had cardiac surgery.

Methods and Results

We performed a retrospective study on 136 patients with RHD who underwent valve replacement surgery. The mean age of the patients was 56.2 years, 59.6% were female, 8.8% patients had diabetes mellitus, and 27.2% of patients had hypertension. Overall, 3 patients died, 2 underwent reoperation, and 25 underwent thoracentesis during the study period. For patients with renal impairment, there was a higher risk of thoracic puncture (odds ratio [OR]: 3.33; 95% confidence interval [CI]: 1.36, 8.11; P < 0.01) and a longer time of drainage (difference in means: 1; 95% CI: 0.88, 1.12; P < 0.01), intensive care unit (ICU) stay (difference in means: 0.2; 95% CI: 0.17, 0.23; P = 0.02), and hospital stay (difference in means: 6.6; 95% CI: 6.15, 7.05; P < 0.01) compared with normal renal function. Furthermore, statins were associated with a reduction in drainage time (difference in means: −1.50; 95% CI: −1.86, −1.14; P = 0.02), ICU stay (difference in means: −0.30; 95% CI: −0.40, −0.20; P = 0.05), and hospital stay (difference in means: −5.40; 95% CI: −6.57, −4.23; P < 0.01) in patients with renal impairment (interaction, P ≤ 0.05 for all), but not in those with normal renal function.

Conclusion

Statins have a greater clinical benefit in perioperative cardiac surgery with renal impairment. Statins are associated with a comparatively lower risk of thoracic puncture, as well as a reduced trend toward a reduction in drainage time, ICU stay, and hospital stay.

A nationwide analysis of re-exploration after liver transplant

BACKGROUND

A retrospective review to investigate rate and outcomes of re-exploration following liver transplantation in the United States.

METHODS

The NIS database was used to examine outcomes of patients who underwent re-exploration following liver transplantation from 2002 to 2012. Multivariate regression analysis was performed to compare outcomes of patients with and without reoperation.

RESULTS

We sampled a total of 12,075 patients who underwent liver transplantation. Of these, 1505 (12.5%) had re-exploration during the same hospitalization. Hemorrhagic (67.9%) and biliary tract anastomosis complication (14.8%) were the most common reasons for reoperation. Patients with reoperation had a significantly higher mortality than those who did not (11.6% vs. 3.8%, AOR: 3.01, P < 0.01). Preoperative coagulopathy (AOR: 1.71, P < 0.01) and renal failure (AOR: 1.57, P < 0.01) were associated with hemorrhagic complications. Peripheral vascular disorders (AOR: 2.15, P < 0.01) and coagulopathy (AOR: 1.32, P < 0.01) were significantly associated with vascular complications. Risk of wound disruption was significantly higher in patients with chronic pulmonary disease (AOR: 1.50, P < 0.01).

CONCLUSION

Re-exploration after liver transplantation is relatively common (12.5%), with hemorrhagic complication as the most common reason for reoperation. Preoperative coagulation disorders significantly increase hemorrhagic and vascular complications. Further clinical trails should investigate prophylactic strategies in high risk patients to prevent unplanned reoperation.

Prediction of bleeding and thrombosis by standard biochemical coagulation variables in haematological intensive care patients

PURPOSE

We assessed the value of standard biochemical coagulation parameters in predicting bleeding, thrombosis and mortality in adult Intensive Care Unit (ICU) patients with haematological malignancies.

METHODS

We screened all patients with acute leukaemia and myelodysplastic syndrome admitted to a university hospital ICU during 2008-2012. Data were obtained from the clinical chemistry laboratory database and patient files. We graded bleeding according to the World Health Organisation (WHO)-system within 24-h, within 5-days and during the whole ICU stay. We analysed the predictive values of laboratory parameters using multiple logistic regression and receiver operator characteristics (ROC) curves. As we previously have established that platelet count at admission was associated with bleeding, we focused on International Normalised Ratio (INR), activated pro-thrombin time (APTT), anti-thrombin, D-dimer and fibrinogen, and markers of infection (C-reactive protein, pro-calcitonin), kidney function (creatinine) and tissue damage (lactate dehydrogenase (LDH)).

RESULTS

We included 116 patients; 66 (57%) had at least one bleeding episode and 11 (9%) patients had at least one thrombotic event. The differences in coagulation values when bleeding compared to baseline values were minor. INR was the only variable we found associated with subsequent bleeding within 24 h from admission to ICU (odds ratio 2.91, 95% CI: 1.01-8.43, P = 0.048). ROC analyses did not show predictive value of any of the other variables with regards to bleeding and none of the variables were associated with thrombosis in adjusted analyses. Increased levels of LDH at admission were associated with increased 7-day and 30-day mortality.

CONCLUSIONS

Increased INR at admission was associated with a higher rate of bleeding in ICU patients with haematological malignancies. No other biochemical coagulation or other parameter had any association with bleeding, thrombosis or mortality except increased LDH, which at ICU admission was associated with increased 30-day mortality.

Systematic review of cortical bone trajectory versus pedicle screw techniques for lumbosacral spine fusion

Fusion of the lumbosacral spine is a common surgical procedure to address a range of spinal pathologies. Fixation in lumbar fusion has traditionally been performed using pedicle screw (PS) augmentation. However, an alternative method of screw insertion via cortical bone trajectory (CBT) has been advocated as a less invasive approach which improves initial fixation and reduces neurovascular injury. There is a paucity of robust clinical evidence to support these claims, particularly in comparison to traditional pedicle screws. This study aims to review the available evidence to assess the merits of the CBT approach. Six electronic databases were searched for original published studies which compared CBT with traditional PS and their findings reviewed. Nine comparative studies were identified through a comprehensive literature search. Studies were classified as retrospective cohort, prospective cohort or case control studies with medium quality as assessed by the GRADE criteria. The available literature is not cohesive regarding outcomes and complications of CBT versus PT procedures. Most studies found no difference in operative time, but reported less blood loss during CBT. Radiological outcomes show no difference in slippage at one year although CBT is associated with greater bone-density compared to PT. Results for post-operative pain are inconclusive.

Prediction of severe bleeding after coronary surgery: the WILL-BLEED Risk Score

Severe perioperative bleeding after coronary artery bypass grafting (CABG) is associated with poor outcome. An additive score for prediction of severe bleeding was derived (n=2494) and validated (n=1250) in patients from the E-CABG registry. Severe bleeding was defined as E-CABG bleeding grades 2–3 (transfusion of >4 units of red blood cells or reoperation for bleeding). The overall incidence of severe bleeding was 6.4 %. Preoperative anaemia (3 points), female gender (2 points), eGFR <45 ml/min/1.73 m2 (3 points), potent antiplatelet drugs discontinued less than five days (2 points), critical preoperative state (5 points), acute coronary syndrome (2 points), use of low-molecular-weight heparin/fondaparinux/unfractionated heparin (1 point) were independent predictors of severe bleeding. The WILL-BLEED score was associated with increasing rates of severe bleeding in both the derivation and validation cohorts (scores 0–3: 2.9 % vs 3.4 %; scores 4–6: 6.8 % vs 7.5 %; scores>6: 24.6 % vs 24.2 %, both p<0.0001). The WILL-BLEED score had a better discriminatory ability (AUC 0.725) for prediction of severe bleeding compared to the ACTION (AUC 0.671), CRUSADE (AUC 0.642), Papworth (AUC 0.605), TRUST (AUC 0.660) and TRACK (AUC 0.640) bleeding scores. The net reclassification index and integrated discrimination improvement using the WILL-BLEED score as opposed to the other bleeding scores were significant (p<0.0001). The decision curve analysis demonstrated a net benefit with the WILL-BLEED score compared to the other bleeding scores. In conclusion, the WILL-BLEED risk score is a simple risk stratification method which allows the identification of patients at high risk of severe bleeding after CABG.

Clinical Trial Registration: NCT02319083 (https://clinicaltrials.gov/ct2/show/NCT02319083)

Bleeding impacting mortality after noncardiac surgery: a protocol to establish diagnostic criteria, estimate prognostic importance, and develop and validate a prediction guide in an international prospective cohort study

INTRODUCTION

Various definitions of bleeding have been used in perioperative studies without systematic assessment of the diagnostic criteria for their independent association with outcomes important to patients. Our proposed definition of bleeding impacting mortality after noncardiac surgery (BIMS) is bleeding that is independently associated with death during or within 30 days after noncardiac surgery. We describe our analysis plan to sequentially 1) establish the diagnostic criteria for BIMS, 2) estimate the independent contribution of BIMS to 30-day mortality and 3) develop and internally validate a clinical prediction guide to estimate patient-specific risk of BIMS.

METHODS

In the Vascular Events In Noncardiac Surgery Patients Cohort Evaluation (VISION) study, we prospectively collected bleeding data for 16 079 patients aged 45 years or more who had noncardiac inpatient surgery between 2007 and 2011 at 12 centres in 8 countries across 5 continents. We will include bleeding features independently associated with 30-day mortality in the diagnostic criteria for BIMS. Candidate features will include the need for reoperation due to bleeding, the number of units of erythrocytes transfused, the lowest postoperative hemoglobin concentration, and the absolute and relative decrements in hemoglobin concentration from the preoperative value. We will then estimate the incidence of BIMS and its independent association with 30-day mortality. Last, we will construct and internally validate a clinical prediction guide for BIMS.

INTERPRETATION

This study will address an important gap in our knowledge about perioperative bleeding, with implications for the 200 million patients who undergo noncardiac surgery globally every year. Trial registration: ClinicalTrials.gov, no NCT00512109.

Risk factors for bleeding after liver biopsy

OBJECTIVE

Determine factors that increase the risk of bleeding after liver biopsy.

METHODS

Retrospective review of radiology and clinical databases from Jan 2008 to Jun 2014 revealed 847 patients with liver biopsy. Of these, 154 (group I) had targeted biopsy of focal lesion and 142 (group 2) had random core biopsy for diffuse liver disease. The rest of the patients were excluded due to insufficient post-biopsy data. Data including pre-biopsy laboratory results, history of transfusion, and biopsy complications were recorded in the study cohort. After review of initial results, a "Risk Score" for bleeding was created using platelet count, INR, estimated glomerular filtration rate (eGFR), and suspicion of malignancy. Zero point was given for normal laboratory results or absence of malignancy. One point was given for mildly abnormal laboratory values or presence of malignancy. Severe biochemical abnormalities, e.g., INR > 2.0, eGFR < 30 mL/min, or platelet count ≤ 50 × 10(9)/L were given two points each. The "Risk Score" was made of adding individual points.

RESULTS

Of 847 patients queried by retrospective database search, 296 had adequate records for the period of 2 weeks prior to biopsy to 4 weeks after biopsy. The remaining patients had liver biopsy as outpatients and probably did not have bleeding complications but no electronic records were found to confirm this. 25 (8.4%) of 296 patients had post-biopsy bleeding, with incidences of 11.7% and 4.9% in groups 1 and 2 (p = 0.04). On logistic regression analysis, the only significant predictor of bleeding was the "Risk Score" (p = 0.01, odds ratio 4.6). There was substantial overlap in INR, and platelet count in bleeders vs. non-bleeders. Pre-biopsy fresh frozen plasma or platelet concentrate infusions did not reduce the risk of bleeding.

CONCLUSION

INR and platelet count are not an independent risk factors for post-biopsy bleeding. A "Risk Score" made up of individual risk factors was a better predictor of bleeding.

Perioperative Approach to Anticoagulants and Hematologic Disorders

Hematologic disorders and patients on anticoagulants or at risk for venous thromboembolism encompass a broad array of diagnoses, which can potentially complicate perioperative planning and management. This article addresses both bleeding and clotting concerns as well as special hematologic issues.

Complications and Mortality in Chronic Renal Failure Patients Undergoing Total Joint Arthroplasty: A Comparison Between Dialysis and Renal Transplant Patients

BACKGROUND

In total joint arthroplasty (TJA) literature, there is a paucity of large cohort studies comparing chronic kidney disease (CKD) and end-stage renal disease (ESRD) vs non-CKD/ESRD patients. Thus, the purposes of this study were (1) to identify inhospital complications and mortality in CKD/ESRD and non-CKD/ESRD patients and (2) compare inhospital complications and mortality between dialysis and renal transplantation patients undergoing TJA.

METHODS

We queried the Nationwide Inpatient Sample database for patients with and without diagnosis of CKD/ESRD and those with a renal transplant or on dialysis undergoing primary or revision total knee or hip arthroplasty from 2007 to 2011. Patient comorbidities were identified using the Elixhauser comorbidity index. International Classification of Diseases, Ninth Revision, codes were used to identify postoperative surgical site infections (SSIs), wound complications, deep vein thrombosis, and transfusions.

RESULTS

Chronic kidney disease/ESRD was associated with greater risk of SSIs (odds ratio [OR], 1.4; P<.001), wound complications (OR, 1.1; P=.01), transfusions (OR, 1.6; P<.001), deep vein thrombosis (OR, 1.4; P=.03), and mortality (OR, 2.1; P<.001) than non-CKD/ESRD patients. Dialysis patients had higher rates of SSI, wound complications, transfusions, and mortality compared to renal transplant patients.

CONCLUSION

Chronic kidney disease/ESRD patients had a greater risk of SSIs and wound complications compared to those without renal disease, and the risk of these complications was even greater in CKD/ESRD patients receiving dialysis. These findings emphasize the importance of counseling CKD patients about higher potential complications after TJA, and dialysis patients may be encouraged to undergo renal transplantation before TJA.

Nephrectomy and inferior vena cava thrombectomy for renal cell carcinoma among patients with impaired renal function: defining predictors of outcomes

BACKGROUND

Management of renal cell carcinoma (RCC) with inferior vena cava thrombus (IVCT) is associated with high morbidity. Chronic kidney disease (CKD) is a known risk factor for perioperative complications in many surgical procedures. The objective of this study was to review the association between preoperative CKD (eGFR < 60 mL/min) and post-operative outcomes in patients with RCC and IVCT undergoing radical nephrectomy (RN) and tumour thrombectomy (TT).

METHODS

A retrospective review of patients with RCC and IVCT treated with RN and TT was carried out. Complications were recorded according to the Clavien-Dindo classification. Multivariable models were fitted using logistic regression analyses for high-grade complications and salvage therapies and linear-regression for intraoperative blood loss (IBL).

RESULTS

One hundred and one patients with RCC and IVCT, treated with RN and TT, were identified. Forty per cent of patients had preoperative CKD. Median IBL was higher in CKD arm (2.5 versus 1.6 L, P = 0.04). In a multivariate linear regression analysis, CKD (beta 1.34, P = 0.01) remained an independent predictor of IBL. High-grade complications were more frequent in the CKD group (34% versus 16%, P = 0.09) and in logistic regression analysis, CKD was an independent predictor of high-grade complications (OR 3.33, 95% CI 1.01-10.9). Furthermore, CKD patients were less likely to be considered for salvage therapies (62% versus 38%, P = 0.02).

CONCLUSIONS

In patients treated with RN and TT, CKD is an independent predictor of perioperative morbidity. This clinical variable should be considered when selecting patients and subsequent efforts should be made to optimize other competing risk factors in order to reduce the incidence of perioperative adverse events in this patient population.

Impact of renal insufficiency on patients with hepatocellular carcinoma undergoing radiofrequency ablation

BACKGROUND AND AIM

Renal insufficiency (RI) is commonly seen in patients with hepatocellular carcinoma (HCC). We aimed to investigate the impact of RI on the long-term survival of HCC patients undergoing radiofrequency ablation (RFA) and to determine the optimal staging strategy for these patients.

METHODS

RI was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m(2) . A total of 123 and 344 patients with and without RI undergoing RFA, respectively, were enrolled. A one-to-one propensity score matching analysis with preset caliper width was performed. The prognostic ability of four currently used staging systems was compared by the Akaike information criterion (AIC).

RESULTS

HCC patients with RI undergoing RFA were older (P < 0.001) and had significantly different baseline characteristics. Of all patients, RI was significantly associated with a decreased long-term survival (P = 0.03). After matching in the propensity model, the baseline characteristics were similar between patients with (n = 92) and without (n = 92) RI. In the propensity model, RI was not significantly associated with a shortened survival (P = 0.273). In the Cox multivariate analysis, Child-Turcotte-Pugh class B or C was identified as the only independent predictor of poor prognosis. Among patients with RI undergoing RFA, the Taipei Integrated Scoring (TIS) system provided the highest homogeneity and lowest AIC value among the currently used staging systems.

CONCLUSIONS

The long-term survival of HCC patients undergoing RFA is not affected by RI. The TIS staging system may provide a better prognostic prediction for HCC patients with RI undergoing RFA.

Acquired bleeding disorders in the elderly

The hemostatic balance changes with advancing age which may be due to factors such as platelet activation, increase of certain clotting factor proteins, slowing of the fibrinolytic system, and modification of the endothelium and blood flow. Generally, this predisposes the elderly to thrombosis rather than bleeding. It often necessitates antiplatelet or anticoagulation therapy, which can cause significant bleeding problems in an aging population. Additionally, changing renal function, modification in immune regulation, and a multitude of other disease processes, can give rise to acquired bleeding disorders. Bleeding can prove difficult to treat in a dynamic environment and in a population that may have underlying thrombotic risk factors.This article discusses some specific challenges of acquired bleeding arising in the elderly. The use of anticoagulation and nonsteroidal anti-inflammatory medications is prevalent in the treatment of the elderly and predisposes them to increased bleeding risk as their physiology changes. When prescribing and monitoring these therapies, it is exceedingly important to weigh thrombotic versus bleeding risks. There are additional rare acquired bleeding disorders that predominantly affect the elderly. One of them is acquired hemophilia, which is an autoimmune disorder arising from antibodies against factor VIII. The treatment challenge rests in the use of hemostatic agents in a population that is already at increased risk for thrombotic complications. Another rare disorder of intensifying interest, acquired von Willebrand syndrome, has a multitude of etiologic mechanisms. Understanding the underlying pathophysiology is essential in making a treatment decision for this disorder.

Chronic kidney disease and perioperative outcomes in urological oncological surgery

OBJECTIVES

To evaluate baseline renal dysfunction among patients undergoing urological oncological surgery and its impact on early postoperative outcomes.

METHODS

Between 2005 and 2011, patients who underwent minimally-invasive or open radical prostatectomy, partial nephrectomy and radical nephrectomy, or open radical cystectomy, respectively, were identified in the National Surgical Quality Improvement Program dataset. Preoperative kidney function was assessed using estimated glomerular filtration rate and staged according to National Kidney Foundation definitions. Multivariable logistic regression was used to model the association between preoperative renal function and the risk of 30-day mortality and major complications. Furthermore the impact of chronic kidney disease on operation time and length of hospital stay was assessed.

RESULTS

Overall, 13,168 patients underwent radical prostatectomy (65.4%), partial nephrectomy (10.7%) and radical nephrectomy (16.1%) and radical cystectomy (7.8%), respectively; 50.1% of evaluable patients had reduced kidney function (chronic kidney disease II), and a further 12.6, 0.7 and 0.9% were respectively classified into chronic kidney disease stages III, IV, and V. Chronic kidney disease was an independent predictor of 30-day major postoperative complications (chronic kidney disease III: odds ratio 1.61, P < 0.001; chronic kidney disease IV: odds ratio 2.24, P = 0.01), of transfusions (chronic kidney disease III: odds ratio 2.14, P < 0001), of prolonged length of stay (chronic kidney disease III: odds ratio 2.61, P < 0.001; chronic kidney disease IV: odds ratio 3.37, P < 0.001; and chronic kidney disease V: odds ratio 1.68; P = 0.03) and of 30-day mortality (chronic kidney disease III: odds ratio 4.15, P = 0.01; chronic kidney disease IV: odds ratio 10.10, P = 0.003; and chronic kidney disease V: odds ratio 17.07, P < 0.001) compared with patients with no kidney disease.

CONCLUSIONS

Renal dysfunction might be underrecognized in patients undergoing urological cancer surgery. Chronic kidney disease stages III, IV and V are independent predictors for poor 30-day postoperative outcomes.

Aspirin and clonidine in non-cardiac surgery: acute kidney injury substudy protocol of the Perioperative Ischaemic Evaluation (POISE) 2 randomised controlled trial

INTRODUCTION

Perioperative Ischaemic Evaluation-2 (POISE-2) is an international 2×2 factorial randomised controlled trial of low-dose aspirin versus placebo and low-dose clonidine versus placebo in patients who undergo non-cardiac surgery. Perioperative aspirin (and possibly clonidine) may reduce the risk of postoperative acute kidney injury (AKI).

METHODS AND ANALYSIS

After receipt of grant funding, serial postoperative serum creatinine measurements began to be recorded in consecutive patients enrolled at substudy participating centres. With respect to the study schedule, the last of over 6500 substudy patients from 82 centres in 21 countries were randomised in December 2013. The authors will use logistic regression to estimate the adjusted OR of AKI following surgery (compared with the preoperative serum creatinine value, a postoperative increase ≥26.5 μmol/L in the 2 days following surgery or an increase of ≥50% in the 7 days following surgery) comparing each intervention to placebo, and will report the adjusted relative risk reduction. Alternate definitions of AKI will also be considered, as will the outcome of AKI in subgroups defined by the presence of preoperative chronic kidney disease and preoperative chronic aspirin use. At the time of randomisation, a subpopulation agreed to a single measurement of serum creatinine between 3 and 12 months after surgery, and the authors will examine intervention effects on this outcome.

ETHICS AND DISSEMINATION

The authors were competitively awarded a grant from the Canadian Institutes of Health Research for this POISE-2 AKI substudy. Ethics approval was obtained for additional kidney data collection in consecutive patients enrolled at participating centres, which first began for patients enrolled after January 2011. In patients who provided consent, the remaining longer term serum creatinine data will be collected throughout 2014. The results of this study will be reported no later than 2015.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01082874.