Perioperative Acute Kidney Injury Research Articles

Analysis of Risk Factors for Perioperative Acute Kidney Injury and Management Strategies.

Acute kidney injury (AKI) is a serious clinical syndrome, and one of the common comorbidities in the perioperative period. AKI can lead to complications in surgical patients and is receiving increasing attention in clinical workup. In recent years, the analysis of perioperative risk factors has become more in-depth and detailed. In this review, the definition, diagnosis, and pathophysiological characteristics of perioperative AKI are reviewed, and the main risk factors for perioperative AKI are analyzed, including advanced age, gender, certain underlying diseases, impaired clinical status such as preoperative creatinine levels, and drugs that may impair renal function such as non-steroidal anti-inflammatory drugs (NASIDs), ACEI/ARB, and some antibiotics. Injectable contrast agents, some anesthetic drugs, specific surgical interventions, anemia, blood transfusions, hyperglycemia, and malnutrition are also highlighted. We also propose potential preventive and curative measures, including the inclusion of renal risk confirmation in the preoperative assessment, minimization of intraoperative renal toxin exposure, intraoperative management and hemodynamic optimization, remote ischemic preadaptation, glycemic control, and nutritional support. Among the management measures, we emphasize the need for careful perioperative clinical examination, timely detection and management of AKI complications, administration of dexmedetomidine for renal protection, and renal replacement therapy. We aim that this review can further increase clinicians' attention to perioperative AKI, early assessment and intervention to try to reduce the risk of AKI.

Mortality and associated risk factors in perioperative acute kidney injury treated with continuous renal replacement therapy

BackgroundPerioperative acute kidney injury (AKI) is associated with multiple postoperative complications leading to prolonged hospital stay and higher costs. AKI requiring continuous renal replacement therapy (CRRT) after surgery has an incidence of 2–6% and mortality approximates 40–60%. Previous studies examining mortality in perioperative AKI patients managed with CRRT have concentrated on cardiac surgery patients and there are very limited data on broad surgical patient populations requiring CRRT. We examined long-term mortality and factors associated with poor outcome in a broad surgical population requiring CRRT for perioperative AKI during a 10-year period.MethodsSurgical patients admitted to the intensive care unit (ICU) of academic tertiary hospital requiring CRRT between years 2010–2019 were included. CRRT was performed using regional citrate-calcium-anticoagulation. Extracted data included patient demographics, comorbidities, and clinical parameters at ICU admission and at the initiation of CRRT. Creatinine and estimated glomerular filtration rate (eGFR) were measured at 1 year after ICU admission.ResultsA total of 157 patients were included in the study. ICU mortality was 42.7%, 90-day mortality 58.0% and 1-year mortality 62.4%. Blood lactate at ICU admission and CRRT initiation were independently associated with mortality in the multivariate models. Patients with lactate > 4 mmol/l had higher mortality than patients with normal lactate (77% vs. 21%) (p < 0.001). Creatinine (p = 0.004) and eGFR (p < 0.001) remained significantly altered at 1 year of follow-up compared to baseline.ConclusionsPatients undergoing surgery and requiring perioperative CRRT in the ICU have a high risk of mortality. Mortality appears to be independently associated with lactate levels.

Acute kidney injury and percutaneous nephrolithotomy: incidence and predictive factors.

Percutaneous nephrolithotomy (PCNL) is the treatment of choice for patients with large stones. The risk of acute kidney injury (AKI) has not been reported in the Western world. Our objective was to assess the frequency of AKI in patients undergoing PCNL and to identify independent predictors of AKI. A retrospective review of PCNL cases performed between January 2014 and June 2019 was reformed. Demographic, laboratory, and intraoperative date were obtained. Perioperative AKI was defined as (1) Increase in serum creatinine by ≥ 0.3mg/dL (≥ 26.5 micromol/L) within 48h, or (2) increase in serum creatinine to ≥ 1.5 times baseline. Multivariable logistic regression analysis was performed to determine the factors influencing AKI. A p value of 0.05 was considered significant. A total of 566 patients were included. Mean age was 58 ± 14.4years. The frequency of AKI was 4.4% (n = 25). The risk factors for AKI after PCNL were having a baseline creatinine > 1.54mg/dl (p = 0.03, odds ratio [OR] = 2.66, confidence interval [CI] = 1.07-6.6), and a preoperative hemoglobin of less than 10.6g/dL (p = 0.02, odds ratio [OR] = 2.47, confidence interval [CI] = 1.09-5.5). Patients without AKI had a median hospitalization of 2days, while those with an AKI were hospitalized for a median of 3days, and this difference was statistically significant (p < 0.001). Perioperative AKI occurs in 4.4% of patients undergoing PCNL. Preoperative hemoglobin and serum creatinine can identify those at increased risk, in whom it may be important to avoid nephrotoxic agents.

A meta-analysis of the cumulative incidence, risk factors, and clinical outcomes associated with chronic kidney disease after liver transplantation.

Chronic kidney disease (CKD) remains a relatively common complication after liver transplantation (LT), and significantly impacts overall survival. We sought to assess the cumulative incidence, risk factors and mortality associated with post-LT CKD. CKD was defined as eGFR <60ml/min/1.73m2 as estimated by the Modified Diet in Renal Disease (MDRD) formula. Single-arm meta-analysis was done to evaluate the cumulative incidence of CKD at 1-, 3-, and 5-year timepoints post-LT. Risk factors for CKD were evaluated using hazard ratios (HR). Twenty-one studies involving 44383 patients were included. Cumulative incidence of stage 3-5 CKD was 31.44% (CI 0.182-0.447), 36.71% (CI 0.188-0.546), and 43.52% (CI 0.296-0.574) at 1, 3, and 5years after LT, respectively. Stage 5 CKD cumulative incidence increased from 0.274% (CI 0.001-0.005) at 1year to 2.06% (CI 0.009-0.045) at 5years post-LT. Age, female sex, diabetes, and peri-operative acute kidney injury (AKI) were significant risk factors for CKD. Stage 4-5 CKD was associated with a decrease in overall survival (HR 3.23, 95% CI 1.74-5.98, P<0.01). CKD after LT is relatively common, and is associated with significantly reduced overall survival. Identification of patients at high risk of developing CKD allows physicians to prophylactically use renal-sparing immunosuppression which may be crucial in achieving desirable clinical outcomes.

Impact of a clinical pathway on acute kidney injury in patients undergoing heart transplant.

To evaluate the impact of a clinical pathway on the incidence and severity of acute kidney injury in patients undergoing heart transplant. This was a 2.5-year retrospective evaluation using 3years of historical controls within a cardiac intensive care unit in an academic children's hospital. Patients undergoing heart transplant between May 27, 2014, and April 5, 2017 (pre-pathway) and May 1, 2017, and November 30, 2019 (pathway) were included. The clinical pathway focused on supporting renal perfusion through hemodynamic management, avoiding or delaying nephrotoxic medications, and providing pharmacoprophylaxis against AKI. There were 57 consecutive patients included. There was an unadjusted 20% reduction in incidence of any acute kidney injury (p=.05) and a 17% reduction in Stage 2/3 acute kidney injury (p=.09). In multivariable adjusted analysis, avoidance of Stage 2/3 acute kidney injury was independently associated with the clinical pathway era (AOR -1.3 [95% CI -2.5 to -0.2]; p=.03), achieving a central venous pressure of or less than 12mmHg (AOR -1.3 [95% CI -2.4 to -0.2]; p=.03) and mean arterial pressure above 60mmHg (AOR -1.6 [95% CI -3.1 to -0.01]; p=.05) in the first 48h post-transplant, and older age at transplant (AOR - 0.2 [95% CI -0.2 to -0.06]; p=.002). This report describes a renal protection clinical pathway associated with a reduction in perioperative acute kidney injury in patients undergoing heart transplant and highlights the importance of normalizing perioperative central venous pressure and mean arterial blood pressure to support optimal renal perfusion.

Long-Term renal function after implantation of continuous-flow left ventricular assist devices: A single center study.

BackgroundImplantable continuous-flow left ventricular assist device (LVAD) improve renal function in advanced heart failure. However, the long-term effects of LVAD on renal function have not been investigated thoroughly. We aimed to assess long-term renal function in patients with LVAD support and to identify predictors for late deterioration in renal function (LDRF).MethodsOne hundred patients underwent LVAD implantation as a bridge to transplant at the University of Tokyo Hospital between May 2011 and December 2018. We assessed renal function at intervals (preoperative, 1, 6, 12, 18, 24 and 30 months after LVAD implantation). We divided patients into two groups: “with LDRF,” whose renal function at 30 months had decreased by >25% compared with preoperatively (n = 14), and “without LDRF” (n = 55).ResultsRenal function improved at 1 month, returned to preoperative levels at 6 months, and remained there up to 30 months after LVAD implantation. However, renal function impairment became evident in patients with LDRF 18 months after LVAD implantation. A ratio of right atrial pressure/pulmonary artery wedge pressure > 0.57 and left ventricular dimension diastole ≤ 67 mm were preoperative independent risk factors for LDRF. In addition, the incidence of perioperative acute kidney injury, ventricular arrhythmia, aortic insufficiency, and late right ventricular failure was significantly higher in patients with LDRF.ConclusionLDRF after LVAD implantation corresponded to several risk factors, including a small left ventricle and LVAD-related complications, such as right ventricular failure.

Editor's Choice – Pre-Operative Moderate to Severe Chronic Kidney Disease is Associated with Worse Short-Term and Mid-Term Outcomes in Patients Undergoing Fenestrated-Branched Endovascular Aortic Repair

To review experience of fenestrated-branched endovascular aortic repair (F-BEVAR) for pararenal/thoraco-abdominal aortic aneurysms (PRAA/TAAA) and to assess the association between pre-operative moderate to severe chronic kidney disease (CKD) and post-operative outcomes.All consecutive patients undergoing (elective and non-elective) F-BEVAR at a single centre (1 January 2011 - 1 July 2019) were identified. Renal function was calculated as the estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease formula. Accordingly, presence of moderate to severe CKD was defined as eGFR < 60 mL/min/1.73m2.Overall, 202 consecutive patients (mean age 72 ± 8 years; 25% women) underwent F-BEVAR for the treatment of PRAA/TAAA during the study period. Of these, 51 had a history of moderate to severe CKD (none on chronic haemodialysis). No statistically significant differences were found in demographics and major comorbidities between patients with or without a history of CKD. The overall peri-operative mortality rate was 2%, without statistically significant differences between study groups (p = .26). Patients with prior CKD had statistically significantly higher rates of acute kidney injury (AKI) (37% vs. 12%, p < .001). At three years, overall survival was statistically significantly lower in patients with history of CKD compared with those without pre-operative CKD (57% vs. 82%, p = .010). Similarly, freedom from renal function decline at three years was statistically significantly poorer in patients with prior history of CKD compared with those without pre-operative CKD (43% vs. 80%, p = .020). In a multivariable analysis CKD was independently associated with higher odds of peri-operative AKI (OR 2.8, 95% CI 1.9 - 5.8, p = .030), renal function decline (OR 4.9, 95% CI 1.7 - 9.2, p = .003), and all cause mortality (HR 3.2, 95% CI 1.2 - 8.6, p = .020).Despite low peri-operative mortality rates that are comparable to patients with unimpaired renal function, occurrence of AKI was statistically significantly higher in subjects with pre-existing moderate to severe CKD. History of CKD was independently associated to renal function decline and poorer midterm survival.

Renal Cell Cancer and Chronic Kidney Disease.

The association between chronic kidney disease (CKD) and renal cell carcinoma (RCC) is bidirectional and multifactorial. Risk factors such as hypertension, diabetes mellitus, obesity, and smoking increase the risk of both CKD and RCC. CKD can lead to RCC via an underlying cystic disease or oxidative stress. RCC can cause CKD because of the tumor itself, surgical reduction of renal mass (either partial or radical nephrectomy), and perioperative acute kidney injury. Medical therapies such as immune checkpoint inhibitors and vascular endothelial growth factor inhibitors can lead to acute kidney injury and resultant CKD. Clinicians need to be aware of the complex, bidirectional interplay between both diseases.

5-Year Outcomes Comparing Surgical Versus Transcatheter Aortic Valve Replacement in Patients With Chronic Kidney Disease

The aim of this study was to compare 5-year cardiovascular, renal, and bioprosthetic valve durability outcomes in patients with severe aortic stenosis (AS) and chronic kidney disease (CKD) undergoing transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR).Patients with severe AS and CKD undergoing TAVR or SAVR are a challenging, understudied clinical subset.Intermediate-risk patients with moderate to severe CKD (estimated glomerular filtration rate <60 mL/min/m2) from the PARTNER (Placement of Aortic Transcatheter Valve) 2A trial (patients randomly assigned to SAPIEN XT TAVR or SAVR) and SAPIEN 3 Intermediate Risk Registry were pooled. The composite primary outcome of death, stroke, rehospitalization, and new hemodialysis was evaluated using Cox regression analysis. Patients with and without perioperative acute kidney injury (AKI) were followed through 5 years. A core laboratory-adjudicated analysis of structural valve deterioration and bioprosthetic valve failure was also performed.The study population included 1,045 TAVR patients (512 SAPIEN XT, 533 SAPIEN 3) and 479 SAVR patients. At 5 years, SAVR was better than SAPIEN XT TAVR (52.8% vs 68.0%; P = 0.04) but similar to SAPIEN 3 TAVR (52.8% vs 58.7%; P = 0.89). Perioperative AKI was more common after SAVR than TAVR (26.3% vs 10.3%; P < 0.001) and was independently associated with long-term outcomes. Compared with SAVR, bioprosthetic valve failure and stage 2 or 3 structural valve deterioration were significantly greater for SAPIEN XT TAVR (P < 0.05) but not for SAPIEN 3 TAVR.In intermediate-risk patients with AS and CKD, SAPIEN 3 TAVR and SAVR were associated with a similar risk for the primary endpoint at 5 years. AKI was more common after SAVR than TAVR, and SAPIEN 3 valve durability was comparable with that of surgical bioprostheses.

Predicting factors of acute kidney injury after partial nephrectomy and its impact on long‐term renal function: A multicentre study of the Turkish Urooncology Association

To investigate the predictors of acute kidney injury (AKI) after partial nephrectomy and the impact of AKI stage on long-term kidney function. Data of 1055 patients who underwent partial nephrectomy between January 2008 and January 2018 at seven separate tertiary centres were analysed. AKI was defined according to AKI Network criteria. The association between pre-operative and perioperative factors and AKI was evaluated using logistic regression analysis. Recovery of at least 90% of baseline glomerular filtration rate 1 year after partial nephrectomy, change of 1 year glomerular filtration rate compared with baseline glomerular filtration rate and stage ≥3 chronic kidney disease (CKD) progression were assessed according to the stage of AKI. AKI was recorded in 281 (26.7%) of 1055 patients after partial nephrectomy, and of these patients, 197 (70.1%) had stage 1, 77 (27.4%) had stage 2 and 7 (2.5%) had stage 3. Higher tumour complexity and baseline glomerular filtration rate were independent predictors for AKI. The proportion of recovering 90% of baseline glomerular filtration rate at 1 year for any patient who had stage ≤1 vs stage 2-3 of AKI was 78.2% (95% CI: 73.2%-83.7%) and 23.8% (95% CI: 14.7%-38.7%), respectively (P<.001). The risk of stage ≥3 CKD progression for any patient who had stage ≤1 vs stage 2-3 of AKI was 6.2% (95% CI: 4.1%-9.2%) and 63.1% (95% CI: 52.5%-75.6%), respectively (P<.001). AKI adversely affects renal function in the long-term after partial nephrectomy and stage 2-3 significantly increases the risk of CKD in the long term.

Does ERAS implementation in gynecologic oncology result in acute kidney injury?

<h3>Objectives:</h3> Enhanced recovery after surgery (ERAS) protocols involve judicious intravenous fluid resuscitation and routine administration of nonsteroidal anti-inflammatory drugs. Potential consequences could include a rise in incidence of acute kidney injury (AKI). A perioperative AKI can further result in increased short-term complications and in-hospital mortality for the patient. A recent study in patients undergoing colorectal surgery showed an increase in postoperative kidney injury from 2.27% to 11.36% after ERAS implementation. There have been no studies to date investigating development of AKI with ERAS in Gynecologic Oncology. Therefore, the primary aim of the current study is to measure the trend of postoperative renal function and the incidence of clinically significant acute kidney injury after ERAS implementation. The secondary outcomes are to identify independent predictors that may increase risk for development of a perioperative AKI. <h3>Methods:</h3> A retrospective cohort study was performed at Abington-Jefferson Hospital in gynecologic oncology, where ERAS was established in 2014. All women who underwent an exploratory laparotomy for benign and malignant etiologies prior to and after implementation of an ERAS protocol were included. Demographic, perioperative and surgical characteristics were collected. All patients above age 18, regardless of comorbid conditions, BMI or baseline kidney function were included. Stage 1 AKI was defined by KDIGO criteria of > 0.3 mg/dl increase within 48 hours. A p-value <0.05 was used to denote significance. <h3>Results:</h3> A total of 274 patients were included in this study: 143 in the non-ERAS cohort and 131 patients in the ERAS group. No significant difference was seen in creatinine levels or glomerular filtration rate after surgical intervention between the two cohorts (p=0.054 and p=0.588, respectively). Similarly, there was no difference in rate of AKI among patients after ERAS within the first 72 hours of surgery (0.021 vs 0.023, p=0.869). Clinically significant kidney injury occurred in six patients. AKI was associated with receipt of a postoperative blood transfusion (p=0.002). However on multivariate analysis, no patient or surgical characteristics including hypertension, blood transfusions, diabetes, intraoperative mean arterial blood pressure, complexity of procedure, age, and length of surgery were predictive of development of AKI. <h3>Conclusions:</h3> No difference in rates of acute kidney injury was detected before and after ERAS implementation in gynecologic oncology. Acute kidney injury seemed to be associated with receipt of postoperative blood products. No other independent predictors of kidney injury were identified. Nonetheless, attention should be paid to patients that may be at an increased of AKI. Further studies are required to determine to whether modification of ERAS protocols for select groups of patients could decrease rates of AKI in the perioperative setting.

Relationship between postoperative immediate serum albumin level and postoperative acute kidney injury after major abdominal surgery in critically ill patients

To investigate the relationship between albumin (ALB) level immediately after major abdominal surgery and postoperative acute kidney injury (AKI) in critically ill patients. A retrospective cohort study was conducted. Patients who accepted the major abdominal surgery admitted to the department of intensive care unit (ICU) of the Peking University First Hospital from June 2017 to July 2018 were enrolled. Clinical data including the postoperative ALB level and renal function were collected. Patients were divided into postoperative AKI group and postoperative non-AKI group according to the AKI diagnosis and staging criteria of Kidney Disease: Improving Global Outcomes (KIDGO). The risk factors of perioperative AKI occurrence were analyzed, and multivariate Logistic regression analysis was performed. The receiver operator characteristic curve (ROC curve) was plotted for the ALB level to predict the occurrence of AKI and to determine the ALB cut-off value. The Kaplan-Meier survival curve of postoperative survival of patients was drawn. A total of 363 critically ill patients underwent major abdominal surgery, and 105 patients (28.9%) suffered from AKI. Compared with the non-AKI group, the patients in the AKI group were older (t = -2.794, P = 0.005), preoperative proportions of diabetes and chronic kidney disease were higher (χ21 = 4.613, χ22 = 5.427, both P < 0.05), the proportion of American Society of Anesthesiologists (ASA) grades and V was higher (χ2 = 19.444, P < 0.001), baseline serum creatinine (SCr) and preoperative brain natriuretic peptide (BNP) levels were higher (U1 = 2.859, U2 = 2.283, both P < 0.05), preoperative ALB level was lower (t = 3.226, P = 0.001), the proportion of preoperative use of contrast media was higher (χ2 = 7.431, P = 0.006), the proportions of emergency surgery and using vasopressor during surgery were higher (χ21 = 4.211, χ 22 = 4.947, both P < 0.05), non-renal SOFA score and acute physiology and chronic health evaluation (APACHE) within 24 hours after ICU admission were higher (U = 2.233, t = 3.130, both P < 0.05), and the proportion of postoperative immediate ALB less than 32 g/L was higher (χ2 = 7.601, P = 0.006). ROC curve analysis showed that the cut-off value of immediate postoperative ALB for predicting postoperative AKI was 32 g/L, with the sensitivity was 86.7%, and the specificity was 28.3%. Multivariate Logistic regression analysis showed that ASA grade, use of contrast before surgery, baseline SCr and postoperative immediate serum ALB level below 32 g/L were independent risk factors for AKI [odds ratio (OR) and 95% confidence interval (95%CI) were 2.248 (1.458-3.468), 2.544 (1.332-4.857), 1.018 (1.008-1.027) and 2.685 (1.383-5.212), respectively, all P < 0.01]. Compared with the non-AKI group, the proportion of patients with AKI undergoing mechanical ventilation in ICU was higher (χ2 = 13.635, P < 0.001), mechanical ventilation duration, length of ICU stay, postoperative hospital stay were longer (U1 = 2.530, U2 = 5.032, U3 = 3.200, all P < 0.05), more postoperative complications except AKI (U = 4.799, P < 0.001), and in-hospital mortality and total hospitalization cost were higher (χ2 = 11.681, U = 3.537, both P < 0.001). Compared with the group with postoperative immediate serum ALB ≥ 32 g/L, the proportion of mechanical ventilation in ICU of the ALB < 32 g/L group was higher (χ2 = 33.365, P < 0.001), the length of ICU stay and postoperative hospital stay were longer (U1 = 3.246, U2 = 4.563, both P < 0.001), more postoperative complications except AKI (U = 3.328, P = 0.001), total hospitalization cost was higher (U = 4.127, P < 0.001). For critically ill patients underwent major abdominal surgery, the postoperative immediate serum ALB level below 32 g/L significantly increased the risk of AKI, which was related to the poor prognosis of the patients.

Pathogenetic mechanisms, epidemiology and classification of acute kidney injury in heart transplant recipients

Kidney injury in heart transplant recipients is of a complex nature and bears the features of all types of cardiorenal interaction impairment. Pre-transplant renal dysfunction, perioperative acute kidney injury, as well as factors associated with graft and immunosuppression, determine the prevalence and severity of kidney pathology in this group of patients. This review examines the pathophysiology of kidney dysfunction in heart failure, the epidemiology, and criteria for acute kidney injury.

Diagnostic timing dependent characteristics of acute kidney injury following hepatectomy: a retrospective historical cohort analysis.

The timing of diagnosis of post-hepatectomy acute kidney injury (AKI) has rarely been investigated. The aim of this retrospective study was to reveal the differences between AKI subtypes following hepatectomy, as classified by timing of diagnosis. Post-hepatectomy AKI was classified as very transient AKI (vtAKI; criteria satisfied by the serum creatinine value immediately after surgery) or non-transient AKI (ntAKI; all other AKI types except for vtAKI). Multivariate logistic regression analyses for both AKI types were performed separately to identify differences in known perioperative AKI risk factors. The impacts of each AKI subtype on postoperative complications, hospital stay and renal outcome at discharge were also evaluated. AKI was diagnosed in 135 of 750 patients (18.0%); 82 and 53 patients were classified as vtAKI and ntAKI, respectively. In multivariate analysis, even among the perioperative factors associated with whole AKI, there were distinct relationships depending on vtAKI or ntAKI. Furthermore, only ntAKI was associated with postoperative complications, longer hospital stays and impaired renal function at discharge. Based on the results of this study, future post-hepatectomy AKI studies should only include ntAKI and exclude vtAKI, as vtAKI has minimal clinical impact despite accounting for a significant proportion of AKI patients. None.

Perioperative acute kidney injury and urine output in lower limb arthroplasties

This study aimed to evaluate the occurrence and perioperative risk factors of acute kidney injury (AKI) in primary elective hip and knee and emergency hip arthroplasty patients. We also aimed to assess the effect of urine output (UOP) as a diagnostic criterion in addition to serum creatinine (sCr) levels. We hypothesized that emergency arthroplasties are prone to AKI and that UOP is an underrated marker of AKI. This retrospective, register-based study assessed 731 patients who underwent primary elective knee or hip arthroplasty and 170 patients who underwent emergency hip arthroplasty at Oulu University Hospital, Finland, between January 2016 and February 2017. Of the elective patients, 18 (2.5%) developed AKI. The 1-year mortality rate was 1.5% in elective patients without AKI and 11.1% in those with AKI (P=.038). Of the emergency patients, 24 (14.1%) developed AKI. The mortality rate was 16.4% and 37.5% in emergency patients without and with AKI, respectively (P=.024). In an AKI subgroup analysis of the combined elective and emergency patients, the mortality rate was 31.3% (n=5) in the sCr group (n=16), 23.5% (n=4) in the UOP group (n=17), and 22.2% (n=2) in AKI patients who met both the sCr and UOP criteria (n=9). Emergency hip arthroplasty is associated with an increased risk of AKI. Since AKI increases mortality in both elective and emergency arthroplasty, perioperative oliguria should also be considered as a diagnostic criterion for AKI. Focusing solely on sCr may overlook many cases of AKI.

28 Diagnosed vs Undiagnosed Chronic Obstructive Pulmonary Disease: Short and Long-term Impact on Coronary Artery Bypass Surgery

Abstract Introduction This study sought to compare clinical outcomes among non-COPD, diagnosed COPD, and undiagnosed COPD patients, in CABG surgery. Method A single-centred retrospective study, from January 2010 to December 2019. Primary outcomes were post-operative complications, lenght of ITU admission and in-hospital staying. Secondary outcomes were re-intervention rate, in-hospital and long-term mortality. Results 4020 patients were divided into: non-COPD – Group A (74.55% n = 2997), diagnosed COPD – Group B (14.78% n = 594), and undiagnosed COPD – Group C (10.67% n = 429). The rate of respiratory complications was noted in this order: Group B &amp;gt; Group C &amp;gt; Group A (p 0.00000002). Perioperative Acute Kidney Injury, wound complications, and in-hospital staying were higher in Group B (p 0.0004, p 0.03, and p 0.0009, respectively). Long-term mortality resulted greater in Group B and C (p 0.0004). No difference in long-term mortality was noted in relation to the expected FEV1% in Group B (p 0.29) and Group C (p 0.82). Conclusions In CABG surgery, patients with diagnosed COPD carry a prolonged in-hospital staying and greater peri-operative complications. Both diagnosed and undiagnosed COPD predispose to respiratory complications and higher long-term mortality rate. Consequently, undiagnosed COPD should be included in the EuroSCORE. Finally, the expected FEV1% appears not to correlate with long-term survival.

Consider Urinary Creatinine Clearance for Perioperative Acute Kidney Injury Management.

Consider Urinary Creatinine Clearance for Perioperative Acute Kidney Injury Management.

Perioperative Acute Kidney Injury after Sequential Bilateral Lung Transplant: Comparing Intraoperative Elective VA ECMO to an "Off Pump" Strategy

<h3>Purpose</h3> Perioperative acute kidney injury (AKI) is associated with worsened outcomes after bilateral orthotopic lung transplantation (BOLT). While elective veno-arterial (VA ECMO) strategies are increasingly common, the incidence of perioperative AKI in the context of various surgical strategies is unclear. In this retrospective observational study of BOLT patients, we propose that AKI rates differ between elective VA ECMO and off-pump (OP) strategies. <h3>Methods</h3> Adult patients undergoing BOLT from 1/1/17 to 9/6/2020 were included. As of Feb 2020, all BOLTs were performed on elective VA ECMO. Patients requiring preoperative or urgent conversion to ECMO, cardiopulmonary bypass, concomitant cardiac surgery, re-transplantation, severe pulmonary hypertension (mean PA pressures >40 mmHg), or missing creatinine (Cr) data were excluded. Patients were stratified into OP and VA ECMO cohorts. VA ECMO patients were matched 1:1 to OP patients based on transplant indication, baseline Cr and transfusion requirements. The primary outcome compared was AKI rates (KDIGO criteria). Secondary outcomes included the ratio of maximum postoperative Cr to baseline, and peak Cr. <h3>Results</h3> 383 BOLT patients were identified. 188 met inclusion criteria, while 19 were missing creatinine data. Of those, 134 patients were available prior to Feb 2020 and 35 between Feb-Sep 2020. We identified 33 matched pairs for comparison. Minimal differences in donor, recipient, and procedural characteristics were seen between matched, paired groups. AKI was more common in the OP compared to the VA ECMO group (27/33 vs. 17/33, p=0.009). Both the ratio of peak relative to baseline Cr (1.6 vs 1.3 g/DL; p=0.022) and peak Cr (1.3 vs 1.0 g/dL; p=0.012) were higher in the OP compared to the VA-ECMO group (Table). <h3>Conclusion</h3> In this retrospective study using matched pairs of BOLT patients, we observed a lower incidence of AKI associated with elective intraoperative VA-ECMO when compared to an off-pump strategy.

Acute kidney injury strongly influences renal function after radical nephroureterectomy for upper tract urothelial carcinoma: A single-centre experience

The aim of our study was to investigate frequency and predictors both of postoperative acute kidney injury (AKI) and renal function decline in a population of consecutive upper tract urothelial carcinoma (UTUC) patients who underwent radical nephroureterectomy (RNU). Between October 2014 and February 2020, 93 patients underwent RNU at our Institution. After considered exclusion criteria, 89 patients were selected. Perioperative clinical factors were retrospectively collected. Estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKDEPI) equation. We defined AKI as an increase in serum creatinine by ≥ 0.3 mg/dl or a 1.5-1.9-fold increase in serum creatinine from baseline to I post-operative day (POD). A significant renal function reduction was defined as an eGFR reduction of 40% from baseline at discharge and at last clinical evaluation. Frequency of AKI and eGFR decline was investigated. Association between perioperative clinical factors and AKI and eGFR reduction at discharged and last follow-up was studied using univariate and multivariate models. AKI was detected at I POD in 45 patients. On multivariate analysis, pre-operative eGFR was an independent predictor of AKI (OR 1.03; p = 0.042). Further, AKI was found to be a significant predictor of eGFR reduction ≥ 40% at discharge at univariate analysis (OR 19.42; p = 0.005) and at multivariate analysis (OR 12.49; p = 0.02). In a multivariate logistic regression model post-operative AKI (OR 5.18; p = 0.033), lack of ipsilateral preoperative hydronephrosis (OR 0.17; p = 0.016), preoperative eGFR (OR 1.04; p = 0.047) and antiplatelet therapy (OR 5.14; p = 0.018) were found to be independent predictors of an eGFR reduction higher than 40% at last clinical evaluation made at a median of 15 (IQR 5-30) months. In our cohort, AKI was present in almost 50% of patients after RNU and it was a strong predictor of renal function decline after RNU.

How new biomarkers aid the anesthetist to detect and prevent perioperative acute kidney injury.

Acute kidney injury (AKI) is underestimated but common in the perioperative setting. Although the association of this syndrome with an increased morbidity and mortality has been well established, little progress has been made in the diagnosis or prevention of AKI in recent years. This is partly due to the late detection of AKI by conventional criteria based of functional biomarkers, serum creatinine, and urine output. In addition, conceptually AKI is now recognized as being part of a continuum, in which preventive intervention is time critical. This review will summarize the current best available evidence and explain why timely perioperative management does have impact on the development of AKI and overall outcomes for patients. Damage biomarkers can reliably identify AKI earlier than conventional functional biomarkers, facilitating more timely preventive intervention. Although the interventions published in the Kidney Disease: Improving Global Outcomes guideline are all important, the most relevant preventive options perioperatively include maintenance of adequate volume status and perfusion pressure, and the focus on balanced crystalloid solutions as maintenance fluid. AKI is a time critical syndrome that requires timely detection and damage biomarkers can help to adjust the perioperative management to prevent further injury.