Early creatinine changes after aortic valve replacement and late survival, heart failure and chronic kidney disease in a national registry.

BACKGROUND: The impact of small increases in serum-creatinine after surgical aortic valve replacement (SAVR) that fail to meet the acute kidney injury stage 1 criteria is unknown. The aim was to investigate prognosis after primary SAVR in patients with small increases in postoperative serum-creatinine. METHODS: In this observational cohort study, we included all adult patients who underwent primary SAVR in Sweden 2009-2022. The main outcome was all-cause mortality. Secondary outcomes were chronic kidney disease and heart failure. Regression standardization addressed confounding. RESULTS: In 16,766 patients, 4,074 (24.2%) had no change in postoperative serum-creatinine, 5,764 (34.3%) had a small increase in postoperative serum-creatinine (0.06 mg/dL≤Δserum-creatinine<0.3 mg/dL), and 2,753 (16.4%) fulfilled the KDIGO acute kidney injury stage 1 criteria. The mean age was 67 years and 31% were female. No significant difference in long-term all-cause mortality was observed in the no-change group at 13 years compared with the small-increase group (absolute survival difference: 2.3% (95%CI: 0-4.6)). A stepwise increase in the risk of 30-day mortality was observed with increasing change in serum-creatinine. At 13 years of follow-up, there was a significant difference in the risk of chronic kidney disease (absolute difference: 2.8% (95%CI: 1.0-4.5)) and heart failure (absolute difference: 3.5% (95%CI: 1.3-5.7)) between the no-change and small-increase groups. CONCLUSIONS: A small increase in postoperative serum-creatinine after SAVR was associated with increased risk of adverse outcomes. The acute kidney injury definition may benefit from including more reliable and specific biomarkers together with small creatinine increases to detect kidney injury.

Advanced chronic kidney disease after surgery and the contribution of acute kidney disease: a national observational cohort study.

BACKGROUND: Limited knowledge exists regarding long-term renal outcomes after noncardiac surgery. This study investigated the incidence of, and risk factors for, developing advanced chronic kidney disease (CKD) and major adverse kidney events within 1 yr of surgery in a nationwide cohort. METHODS: Adults without renal dysfunction before noncardiac surgery in Sweden were included between 2007 and 2013 in this observational multicentre cohort study. We analysed data from a national surgical database linked to several national and quality outcome registries. Associations of perioperative risk factors with advanced CKD (estimated glomerular filtration rate [eGFR] <30 ml min-1 1.73 m-2) and major adverse kidney events within 1 yr (MAKE365, comprising eGFR <30 ml min-1 1.73 m-2, chronic dialysis, death) were quantified. RESULTS: Of 237,124 patients, 1597 (0.67%) developed advanced CKD and 16,789 (7.1%) developed MAKE365. Risk factors for advanced CKD included higher ASA physical status, urological surgery, extended surgical duration, prolonged postoperative hospital stay, repeated surgery, and postoperative use of renin-angiotensin-aldosterone system blockers. Advanced acute kidney disease (AKD) (eGFR <30 ml min-1 1.73 m-2 within 90 postoperative days) occurred in 1661 (0.70%) patients and was associated with advanced CKD (subdistribution hazard ratio [SHR] 44.5, 95% confidence interval [CI] 38.7-51.1) and MAKE365 (hazard ratio [HR] 6.60, 95% CI 6.07-7.17). Among patients with advanced AKD after surgery 36% developed advanced CKD at 1 yr after surgery and 51% developed MAKE365. CONCLUSIONS: Advanced CKD within 1 yr after surgery is uncommon but clinically important in patients without preoperative renal dysfunction. Advanced AKD after surgery constitutes a major risk factor for advanced CKD and MAKE365.

Increasing perioperative age and comorbidity: a 16-year cohort study at two University hospital sites in Sweden.

BACKGROUND: Increasing life expectancy affects all aspects of healthcare. During surgery, elderly patients are prone to complications and have a higher risk of death. The authors aimed to investigate if adult patients undergoing surgery at a large Swedish university hospital were getting older and sicker over time and if this potential shift in age and illness severity was associated with higher patient mortality rates. MATERIALS AND METHODS: This was a 16-year cohort study on all surgical procedures performed in adult patients 2006-2021 at two sites of Karolinska University Hospital. Study data was obtained from the surgical system, electronic medical records, and cause-of-death register. Information on age, sex, American Society of Anesthesiologists (ASA) classification, date, type, acuity and duration of surgery was collected. ICD codes were used to calculate the Charlson comorbidity index (CCI). Short-term, medium-term and long-term mortality rates were assessed. Logistic regression models were used to evaluate changes over time. RESULTS: There were 622 814 surgical procedures 2006-2021. Age, ASA classification, and CCI increased over time ( P <0.0001). The proportions of age older than or equal to 60 years increased from 41.8 to 52.8% and of ASA class greater than or equal to 3 from 22.5 to 47.6%. Comparing 2018-2021 with 2006-2009, odds ratios (95% CIs) of 30-day, 90-day and 365-day mortality, adjusted for age, sex, non-elective surgery and ASA classification, decreased significantly to 0.75 (0.71-0.79), 0.72 (0.69-0.76), and 0.76 (0.74-0.79), respectively. CONCLUSION: Although the surgical population got older and sicker during the 16-year study period, short-term, medium-term and long-term mortality rates decreased significantly. These demographic shifts must be taken into account when planning for future healthcare needs to preserve patient safety.

Association of Preoperative Renal-Resistive Index With Long-term Renal and Cardiovascular Outcomes After Cardiac Surgery.

OBJECTIVE: To investigate the association of elevated preoperative renal-resistive index (RRI) with persistent renal dysfunction, major adverse kidney events (MAKE), and major adverse cardiovascular events (MACE) after cardiac surgery. DESIGN: Observational cohort study. SETTING: University hospital. PARTICIPANTS: Ninety-six adult patients undergoing cardiac surgery. INTERVENTIONS: RRI measurement the day before surgery. MEASUREMENTS AND MAIN RESULTS: Fifty-eight patients (60%) had elevated RRI ≥0.70. Five years after surgery, persistent renal dysfunction (sustained decline in estimated glomerular filtration rate ≥25%) had occurred in 25 patients (26%), MAKE (persistent renal dysfunction, renal replacement therapy, or death) in 34 (35%), and MACE (myocardial infarction, unstable angina, decompensated heart failure, stroke, or cardiovascular death) in 28 (29%). RRI was higher in patients who developed persistent renal dysfunction (median, 0.78 [IQR, 0.74-0.82] v 0.70 [0.66-0.77], p = 0.001), MAKE (0.77 [0.72-0.81] v 0.68 [0.65-0.76], p = 0.002), and MACE (0.77 [0.72-0.81] v 0.70 [0.66-0.77], p = 0.006). Patients with elevated RRI had a significantly higher cumulative incidence of all long-term outcomes. After adjustment for baseline renal function and heart failure, elevated RRI was associated with persistent renal dysfunction (hazard ratio [HR], 5.82 [95% CI, 1.71-19.9]), MAKE (HR, 4.21 [1.59-11.1]), and MACE (HR, 2.81 [1.03-7.65]). CONCLUSIONS: Elevated preoperative RRI is associated with persistent renal dysfunction, MAKE, and MACE after cardiac surgery. Preoperative RRI may be used for long-term risk assessment in patients undergoing cardiac surgery.

Risk factors for new antidepressant use after surgery in Sweden: a nationwide, observational cohort study.

Background: Whilst somatic complications after major surgery are being increasingly investigated, the research field has scarce data on psychiatric outcomes such as postoperative depression. This study evaluates the impact of patient and surgical factors on the risk of depression after surgery using the proxy measure of prescribed and collected antidepressants. Methods: An observational, registry-based, national multicentre cohort study of individuals ≥18 yr of age who underwent noncardiac surgery between 2007 and 2014. Exclusion criteria included history of antidepressant use defined by collection of a prescription within 5 yr before surgery. Participants were identified using a surgical database from 23 Swedish hospitals and data were linked to National Board of Health and Welfare registers for collection of prescribed antidepressants. Descriptive statistics were used for baseline data and logistic regression for predictive factors. Results: Of 223 617 patients, 4.9% had a new prescription of antidepressants collected 31-365 days after surgery. Antidepressant prescription was associated with increasing age, female sex, and more comorbidities. The incidence of antidepressant prescription was highest after neurosurgery, vascular, and thoracic surgery. Affective and anxiety disorders were risk factors. In the whole cohort and within the aforementioned surgical subtypes, acute and cancer surgery increased the risk of antidepressant prescription. Conclusions: This study brings novel insights to the epidemiology of postoperative antidepressant treatment in antidepressant-naive patients. One in 20 postoperative patients are prescribed antidepressants but with knowledge of risk factors, interventional strategies can be tested.

The Association Between Acute Kidney Injury and Mortality After Coronary Artery Bypass Grafting Was Similar in Women and Men.

OBJECTIVE: To assess sex differences in short- and long-term mortality in patients who develop acute kidney injury (AKI) after coronary artery bypass grafting (CABG). DESIGN: An observational cohort study. SETTING: A multicenter, nationwide, population-based, observational cohort study. PARTICIPANTS: All patients (n = 32,013) who underwent primary nonemergent isolated CABG in Sweden between January 1, 2003, and December 31, 2013. INTERVENTIONS: AKI and its association with 90-day mortality were analyzed using logistic regression. AKI and its association with long-term mortality were analyzed using Cox regression analysis. MEASUREMENTS AND MAIN RESULTS: AKI was defined as an absolute increase by 26 µmol/L or a relative increase by 50% postoperatively compared with the preoperative serum creatinine concentration. Ninety-day mortality was defined as death by any cause within 90 days after surgery. Long-term mortality was defined as death by any cause from day 91 after surgery to the end of the study period. In total, 13.9% of women and 14.4% of men developed AKI after CABG. The multivariate-adjusted odds ratio (95% confidence interval [CI]) for death within 90 days in patients with AKI compared to those without AKI was 5.1 (3.6-7.2) and 5.2 (4.2-6.6) in women and men, respectively (p for interaction = 0.74). The multivariate-adjusted hazard ratio (95% CI) for long-term death in those with AKI compared to those without AKI was 1.4 (1.2-1.7) and 1.3 (1.2-1.4) in women and men, respectively (p for interaction = 0.27). CONCLUSION: AKI after CABG was associated with a similar increase in 90-day and long-term mortality in both women and men.

Experiences of Renal Replacement Therapy Delivery in Swedish Intensive Care Units during the COVID-19 Pandemic.

BACKGROUND: The COVID-19 pandemic led to a rapidly increased demand for intensive care unit (ICU) and renal replacement therapy (RRT) worldwide. RRT delivery was threatened by a lack of specially trained staff and equipment. We investigated how the first wave of COVID-19 affected RRT delivery in Swedish ICUs. METHODS: An Internet-based questionnaire was sent to ICU lead physicians which included quantitative and qualitative questions regarding RRT demand, equipment availability, and use of continuous renal replacement therapy (CRRT), intermittent haemodialysis (IHD), and peritoneal dialysis (PD) during spring 2020. RESULTS: Twenty-five ICUs responded and these treated 64% of COVID-19 ICU patients in Sweden. ICU capacity increased by 292% (IQR 171-347%). Median peak capacity was reached during the 18th week of the year. RRT use increased overall by 133% and in Stockholm by 188%. 36% of units sequestered CRRT machines. IHD was used in 68% and PD in 12% of ICUs. RRT fluid and filter shortages were experienced by 45% and 33% of wards, respectively; consequently, prescription alterations were made by 24% of ICUs. Calcium solution shortages were reported in 12% of units that led to citrate protocol changes. Staffing shortages resulted in RRT sometimes being delivered by non-RRT-trained staff, safety incidents relating to this occurred, although no patient harm was reported. CONCLUSION: During the first wave of the COVID-19 pandemic, RRT demand increased extensively causing staff and equipment shortages, altered CRRT protocols, and increased use of IHD and PD. The impact on patient outcomes should be assessed to effectively plan for further surge capacity RRT demand.

Pediatric Prehospital Advanced Airway Management by Anesthesiologist and Nurse Anesthetist Staffed Critical Care Teams.

INTRODUCTION: Prehospital pediatric tracheal intubation (TI) is a possible life-saving intervention that requires adequate experience to mitigate associated complications. The pediatric airway and respiratory physiology present challenges in addition to a relatively rare incidence of prehospital pediatric TI. STUDY OBJECTIVE: The aim of this study was to describe characteristics and outcomes of prehospital TI in pediatric patients treated by critical care teams. METHODS: This is a sub-group analysis of all pediatric (<16 years old) patients from a prospective, observational, multi-center study on prehospital advanced airway management in the Nordic countries from May 2015 through November 2016. The TIs were performed by anesthesiologists and nurse anesthetists staffing six helicopter and six Rapid Response Car (RRC) prehospital critical care teams. RESULTS: In the study, 74 children were tracheal intubated, which corresponds to 3.7% (74/2,027) of the total number of patients. The pediatric patients were intubated by very experienced providers, of which 80% had performed ≥2,500 TIs. The overall TI success rate, first pass success rate, and airway complication rate were in all children (<16 years) 98%, 82%, and 12%. The corresponding rates among infants (<2 years) were 94%, 67%, and 11%. The median time on scene was 30 minutes. CONCLUSION: This study observed a high overall prehospital TI success rate in children with relatively few associated complications and short time on scene, despite the challenges presented by the pediatric prehospital TI.

Pre-hospital emergency anaesthesia in trauma patients treated by anaesthesiologist and nurse anaesthetist staffed critical care teams.

BACKGROUND: Pre-hospital tracheal intubation in trauma patients has recently been questioned. However, not only the trauma and patient characteristics but also airway provider competence differ between systems making simplified statements difficult. METHOD: The study is a subgroup analysis of trauma patients included in the PHAST study. PHAST was a prospective, observational, multicentre study on pre-hospital advanced airway management by anaesthesiologist and nurse anaesthetist manned pre-hospital critical care teams in the Nordic countries May 2015-November 2016. Endpoints include intubation success rate, complication rate (airway-related complication according to Utstein Airway Template by Sollid et al), scene time (time from arrival of the critical care team to departure of the patient) and pre-hospital mortality. RESULT: The critical care teams intubated 385 trauma patients, of which 65 were in shock (SBP <90 mm Hg), during the study. Of the trauma patients, 93% suffered from blunt trauma, the mean GCS was 6 and 75% were intubated by an experienced provider who had performed >2500 tracheal intubations. The pre-hospital tracheal intubation overall success rate was 98.6% and the complication rate was 13.6%, with no difference between patients with or without shock. The mean scene time was significantly shorter in trauma patients with shock (21.4 min) compared to without shock (21.4 vs 25.1 min). Following pre-hospital tracheal intubation, 97% of trauma patients without shock and 91% of the patients in shock with measurable blood pressure were alive upon arrival to the ED. CONCLUSION: Pre-hospital tracheal intubation success and complication rates in trauma patients were comparable with in-hospital rates in a system with very experienced airway providers. Whether the short scene times contributed to a low pre-hospital mortality needs further investigation in future studies.

Perioperative fluid balance and major postoperative complications in surgery for advanced epithelial ovarian cancer.

OBJECTIVE: Appropriate fluid balance in the perioperative period is important as both hypo- and hypervolemia are associated with increased risk of complications. Women undergoing cytoreductive surgery (CRS) for advanced epithelial ovarian cancer (EOC) may have major fluid shifts. The optimal perioperative fluid balance in these women is yet to be determined. Our objective was to investigate the association between perioperative fluid balance and major postoperative complications. METHODS: Women with advanced stage EOC who underwent surgery at Karolinska University Hospital, Stockholm, Sweden were identified from the institutional database. Women subjected to surgery with curative intent were included in the analysis. Additional data were retrieved from medical records. The association between perioperative fluid balance and major postoperative complications was investigated by multivariable regression and adjusted for predefined confounders. RESULTS: Of the 270 women identified in the institutional database during 2014-2017, 184 women were included in the analyses. Of these women, 22% (n = 40) experienced a major postoperative complication. The fully adjusted odds of major postoperative complications increased when perioperative fluid balance exceeded >3000 mL, (Odds Ratio (OR) 4.85, 95% Confidence Interval (CI) 1.23-19.2, p = 0.02) and > 5000 mL (OR 33.7, 95% CI 4.13-275, p < 0.01). There was no association between negative fluid balance and major postoperative complications (OR 3.33, 95% CI 0.25-44.1, p = 0.36). CONCLUSIONS: Fluid balance >3000 mL perioperatively during surgery for advanced EOC increased the odds of major postoperative complications. Management of perioperative fluid balance in advanced EOC surgery remains a challenge.

Renal resistive index is associated with acute kidney injury in COVID-19 patients treated in the intensive care unit.

BACKGROUND: Renal resistive index (RRI) is a promising tool for the assessment of acute kidney injury (AKI) in critically ill patients in general, but its role and association to AKI among patients with Coronavirus disease 2019 (COVID-19) is not known. OBJECTIVE: The aim of this study was to describe the pattern of RRI in relation to AKI in patients with COVID-19 treated in the intensive care unit. METHODS: In this observational cohort study, RRI was measured in COVID-19 patients in six intensive care units at two sites of a Swedish University Hospital. AKI was defined by the creatinine criteria in the Kidney Disease Improving Global Outcomes classification. We investigated the association between RRI and AKI diagnosis, different AKI stages and urine output. RESULTS: RRI was measured in 51 patients, of which 23 patients (45%) had AKI at the time of measurement. Median RRI in patients with AKI was 0.80 (IQR 0.71-0.85) compared to 0.72 (IQR 0.67-0.78) in patients without AKI (p = 0.004). Compared to patients without AKI, RRI was higher in patients with AKI stage 3 (median 0.83, IQR 0.71-0.85, p = 0.006) but not in patients with AKI stage 1 (median 0.76, IQR 0.71-0.83, p = 0.347) or AKI stage 2 (median 0.79, min/max 0.79/0.80, n = 2, p = 0.134). RRI was higher in patients with an ongoing AKI episode compared to patients who never developed AKI (median 0.72, IQR 0.69-0.78, p = 0.015) or patients who developed AKI but had recovered at the time of measurement (median 0.68, IQR 0.67-0.81, p = 0.021). Oliguric patients had higher RRI (median 0.84, IQR 0.83-0.85) compared to non-oliguric patients (median 0.74, IQR 0.69-0.81) (p = 0.009). After multivariable adjustment, RRI was independently associated with AKI (OR for 0.01 increments of RRI 1.22, 95% CI 1.07-1.41). CONCLUSIONS: Critically ill COVID-19 patients with AKI have higher RRI compared to those without AKI, and elevated RRI may have a role in identifying severe and oliguric AKI at the bedside in these patients.

Gait Speed at Discharge and Risk for Readmission or Death: A Prospective Study of an Emergency Ward Population.

BACKGROUND: There has been a growing interest in measuring gait speed for assessing long-term mortality and risk for hospital readmission in different populations. OBJECTIVE: We studied the association between a 10-meter gait speed test at hospital discharge and the risk for 30- and 90-day hospital readmission or death in a mixed population of patients hospitalized for emergency care. PATIENTS AND METHODS: Patients were prospectively included from 5 wards at the Karolinska University Hospital. The 10-meter gait speed test was measured on the day of discharge. Statistical analysis was performed using logistic regression. RESULTS: A total of 344 patients were included. Forty-one patients (n=41) were readmitted to hospital or died within 30 days, and 81 were readmitted or died within 90 days after discharge. Readmitted patients were older and had more comorbidities. A 0.1 m/s reduction in gait speed was associated with a 13% greater odds of readmission or death within 30 days (OR 1.13 [95% CI 1.00-1.26]). The area under the receiver operating characteristic curve (AUC) was 0.59 (95% CI 0.51-0.68). The results were similar for 90-day readmission or death where a 0.1 m/s decrement in gait speed was associated with an OR of 1.13 (95% CI 1.04-1.24). When age, eGFR, hemoglobin concentration, and active cancer, which all were univariate predictors of 30-day readmissions, were added to the model it yielded an AUC of 0.68 (95% CI 0.60 to 0.77). CONCLUSION: In a mixed population of patients hospitalized for emergency care, low gait speed at discharge was associated with an increased risk of 30- and 90-day readmission or death. However, the test did not discriminate well between those who were readmitted or died and those who did not; therefore we do not recommend its use as a stand-alone test in this population.

Feasibility of renal resistive index measurements performed by an intermediate and novice sonographer in a volunteer population.

BACKGROUND: The Doppler-derived renal resistive index (RRI) is emerging as a promising bedside tool for assessing renal perfusion and risk of developing acute kidney injury in critically ill patients. It is not known what level of ultrasonography competence is needed to obtain reliable RRI values. OBJECTIVE: The aim of this study was to evaluate the feasibility of RRI measurements by an intermediate and novice sonographer in a volunteer population. METHODS: After a focused teaching session, an intermediate (resident), novice (medical student) and expert sonographer performed RRI measurements in 23 volunteers consecutively and blinded to the results of one another. Intraclass correlation coefficients and Bland-Altman plots were used to evaluate interobserver reliability, bias and precision. RESULTS: Both non-experts were able to obtain RRI values in all volunteers. Median RRI in the population measured by the expert was 0.58 (interquartile range 0.52-0.62). The intraclass correlation coefficient was 0.96 (95% confidence interval 0.90-0.98) for the intermediate and expert, and 0.85 (95% confidence interval 0.69-0.94) for the novice and expert. In relation to the measurements of the expert, both non-experts showed negligible bias (mean difference 0.002 [95% confidence interval - 0.005 to 0.009, p = 0.597] between intermediate and expert, mean difference 0.002 [95% confidence interval - 0.011 to 0.015, p = 0.752] between novice and expert) and clinically acceptable precision (95% limits of agreement - 0.031 to 0.035 for the intermediate, 95% limits of agreement - 0.056 to 0.060 for the novice). CONCLUSIONS: RRI measurements by both an intermediate and novice sonographer in a volunteer population were reliable, accurate and precise after a brief course. RRI is easy to learn and feasible within the scope of point-of-care ultrasound.

Acute kidney injury in patients presenting with chest pain to the emergency department, a descriptive study of the most common discharge diagnoses and mortality.

OBJECTIVE: To describe patients presenting with chest pain to the emergency department (ED) according to acute kidney injury (AKI) status at arrival, with a focus on the most common discharge diagnoses and on long-term mortality. METHODS: All adult patients visiting the Karolinska University Hospital ED between December 2010 and October 2014 with a principal complaint of chest pain were included. AKI at arrival was defined as an increase in presentation serum creatinine concentration of at least 26 µmol/l ( ≥ 0.3 mg/dl) or at least 50% above baseline. Risk ratios (RR) with 95% confidence intervals (CIs) between the AKI and no-AKI groups were calculated for the most common discharge diagnoses in the AKI group. Hazard ratios for long-term mortality were calculated using Cox regression models with adjustment for covariates. RESULTS: In total, 8480 patients were included, of whom 476 (5.6%) had AKI. AKI patients were older and had more comorbidities. It was more common in AKI patients compared to no AKI patients to be diagnosed with heart failure, RR 3.03 (CI: 2.15-4.26) and myocardial infarction RR 1.44 (CI: 1.01-2.04). During a median follow-up of 3.2 years (interquartile range: 2.1-4.3), 37% of the patients with AKI died compared with 16% of patients without AKI. The multivariable adjusted hazard ratio of death for AKI compared with no AKI was 1.30 (95% CI: 1.10-1.53). CONCLUSION: When attending the ED, patients with chest pain and AKI were more likely to be diagnosed with heart failure and myocardial infarction and had an increased long-term mortality compared with patients with no AKI.

Heart failure and the risk of acute kidney injury in relation to ejection fraction in patients undergoing coronary artery bypass grafting.

BACKGROUND: We studied the association between heart failure with reduced or preserved ejection fraction (EF) and the risk of acute kidney injury (AKI) in patients undergoing coronary artery bypass surgery (CABG). METHODS: We included all patients who underwent isolated CABG in Sweden 2003 to 2013. AKI was defined according to the Kidney Disease Improving Global Outcomes definition, as an increase in postoperative serum creatinine concentration by ≥26 µmol/L or ≥50%, compared to preoperative values. Adjusted odds ratios (OR) for AKI were calculated using logistic regression for patients with and without heart failure, and among patients with heart failure, by EF categories (<30% severely reduced; 30-40% moderately reduced; ≥50% preserved). RESULTS: Included were 36,403 patients of whom 3914 (11%) had heart failure. In patients with heart failure, 26% developed AKI compared with 14% in patients without heart failure. After adjustment for background characteristics, including preoperative kidney function and EF, the OR for AKI was 1.12 (95% CI 1.02-1.23) in patients with heart failure compared with no heart failure. Among patients with heart failure, the adjusted OR for AKI among patients with EF <30% vs. ≥50% was 1.32 (95% CI 1.06-1.65) and for 30-49% vs. ≥50% 1.06 (95% CI 0.87-1.28), respectively. CONCLUSION: Patients with heart failure who underwent CABG had an increased risk for AKI postoperatively even after adjustment for comorbidity such as EF. Among patients with heart failure, having a severely reduced EF was associated with AKI compared to patents with preserved EF.

Acute kidney injury-an overview of diagnostic methods and clinical management.

Acute kidney injury (AKI) is a common condition in multiple clinical settings. Patients with AKI are at an increased risk of death, over both the short and long term, and of accelerated renal impairment. As the condition has become more recognized and definitions more unified, there has been a rapid increase in studies examining AKI across many different clinical settings. This review focuses on the classification, diagnostic methods and clinical management that are available, or promising, for patients with AKI. Furthermore, preventive measures with fluids, acetylcysteine, statins and remote ischemic preconditioning, as well as when dialysis should be initiated in AKI patients are discussed. The classification of AKI includes both changes in serum creatinine concentrations and urine output. Currently, no kidney injury biomarkers are included in the classification of AKI, but proposals have been made to include them as independent diagnostic markers. Treatment of AKI is aimed at addressing the underlying causes of AKI, and at limiting damage and preventing progression. The key principles are: to treat the underlying disease, to optimize fluid balance and optimize hemodynamics, to treat electrolyte disturbances, to discontinue or dose-adjust nephrotoxic drugs and to dose-adjust drugs with renal elimination.

Preoperative Renal Resistive Index Predicts Risk of Acute Kidney Injury in Patients Undergoing Cardiac Surgery.

OBJECTIVE: To investigate whether an elevated preoperative renal resistive index (RRI) predicts acute kidney injury (AKI) in patients undergoing cardiac surgery. DESIGN: Prospective cohort study. SETTING: University hospital. PARTICIPANTS: Cohort of 96 adult cardiac surgical patients. INTERVENTIONS: Resistive index was measurement the day before surgery. MEASUREMENTS AND MAIN RESULTS: Renal Doppler was used to measure the resistive index in renal cortical or arcuate arteries the day before surgery. An elevated RRI was defined as≥0.7. AKI was defined as an absolute increase in postoperative compared with preoperative serum creatinine levels by≥26 µmol/L or a relative increase by≥50% or a postoperative urine output<0.5 mL/kg for 6 hours or longer. The relative risk of AKI in patients with an elevated RRI compared with those without an elevated RRI was analyzed using logistic regression. Among patients with an RRI<0.7, 6 (16%) developed AKI compared with 21 (36%) with an RRI≥0.7. The mean increases in postoperative serum creatinine levels were 12 µmol/L in those with an RRI<0.7 and 30 µmol/L in those with an RRI≥0.7. The crude odds ratio for AKI in patients with an RRI≥0.7 was 3.03 (1.09-8.42) compared with those with an RRI<0.7. After multivariable adjustment, the odds ratio was 2.95 (0.97-9.00). CONCLUSIONS: Patients with an elevated preoperative RRI have an increased risk of developing AKI after cardiac surgery. In combination with other markers, the RRI might be a tool for identifying patients with an increased risk of developing AKI.

[Important to investigate the cause of acute kidney injury. Treatment should aim to limit the damage and prevent progression]. / Viktigt utreda orsaken till akut njurskada - Behandlingen ska sikta på att begränsa skadan och förhindra progress.

An acute worsening of renal function, so called acute kidney injury, is common in patients admitted to hospital. Acute kidney injury is associated with an increased long-term risk for chronic kidney disease, myocardial infarction, heart failure, and death. In order to prevent further deterioration of kidney function early identification of causes for acute kindey injury is of utmost importance. In most cases, there is no specific treatment of acute kidney injury, but several general principles should be followed: to strive for normovolemia, optimize hemodynamics, treat electrolyte disturbances, discontinue nephrotoxic agents, and to adjust dosages of medications which are renally eliminated. The aim with this review was to provide an overview of the current knowledge for the initial management of acute kidney injury and to summarize the most important measures to take.

[Acute kidney injury is a common and serious condition. The clinical significance is great and probably underestimated]. / Akut njurskada är ett vanligt och allvarligt tillstånd - Den kliniska betydelsen är stor och sannolikt underskattad.

Acute kidney injury, previously called acute renal failure, is very common in different health care settings. Acute kidney injury is strongly related to an increased risk of death, myocardial infarction, heart failure and dialysis-dependent chronic kidney disease. The established classification of acute kidney injury, KDIGO, uses changes in serum creatinine values, and/or urine output to define different stages (stages 1-3). Acute kidney injury stage 1 is defined as an increase in serum creatinine levels of 26 µmol/l, or an 1.5-2-fold increase in serum creatinine levels compared with baseline values, which often goes undetected. The aim of this review was to give an overview of the classification, epidemiology, and importance of acute kidney injury for prognosis in different clinical settings.