Acute kidney injury following total joint arthroplasty: retrospective analysis

Acute Kidney Injury After Total Hip and Knee Arthroplasty. What Is the Culprit?

Background

Acute kidney injury (AKI) is associated with increased complications after total hip arthroplasty (THA) and total knee arthroplasty (TKA). The purpose of this study was to determine the risk factors for AKI after THA and TKA and evaluate if preoperative use of antihypertensive drugs is a risk factor for AKI.

Methods

A retrospective review of 7406 primary TKAs and THAs (4532 hips and 2874 knees) from 2013 to 2019 was performed. The following preoperative variables were obtained from medical records: medications, chemistry 7 panel, Elixhauser comorbidities, and demographic factors. AKI was defined as an increase in serum creatinine by 26.4 μmol·L-1. Multivariate analysis was performed to identify the risk factors.

Results

The overall incidence of postoperative AKI was 6.2% (n = 459). Risk factors for postoperative AKI were found to be: chronic kidney disease (odds ratio [OR] = 7.09; 95% confidence interval [CI]: 4.8-9.4), diabetes (OR: 5.03; 95% CI: 2.8-6.06), ≥3 antihypertensive drugs (OR: 4.2; 95% CI: 2.1-6.2), preoperative use of an angiotensin receptor blockers or angiotensin-converting enzyme inhibitors (OR: 3.8; 95% CI: 2.2-5.9), perioperative vancomycin (OR: 2.7; 95% CI: 1.8-4.6), and body mass index >40 kg/m2 (OR: 1.9; 95% CI: 1.3-3.06).

Conclusions

We have identified several modifiable risk factors for AKI that can be optimized prior to an elective THA or TKA. The use of certain antihypertensive agents namely angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and multidrug antihypertensive regimens were found to significantly increase the risk of AKI. Therefore, perioperative management of patients undergoing joint replacement should include medical comanagement with a focus on careful management of antihypertensives.

Determination of Risk Factors for Postoperative Acute Kidney Injury in Patients With Gynecologic Malignancies

Background Postoperative acute kidney injury (AKI) is an important cause of mortality and morbidity among surgical patients. There is little information on the occurrence of AKI after operations for gynecologic malignancies. This study aimed to determine the incidence of AKI in patients who underwent surgery for gynecological malignancies and determine the risk factors in those who developed postoperative AKI. Methodology A total of 1,000 patients were enrolled retrospectively from January 2007 to March 2013. AKI was defined according to the Kidney Disease Improving Global Outcomes 2012 Clinical Practice Guideline for Acute Kidney Injury. Perioperative variables of patients were collected from medical charts. Results The incidence of postoperative AKI was 8.8%, with stage 1 occurring in 5.9%, stage 2 in 2.4%, and stage 3 in 0.5% of the patients. Patients who had AKI were significantly older, had higher body mass index (BMI) higher preoperative C-reactive protein (CRP) levels, and more frequently had a history of distant organ metastasis when compared with those who did not have AKI. When compared with patients who did not develop AKI postoperatively, longer operation times and intraoperative usage of higher amounts of erythrocyte suspension and fresh frozen plasma were seen in those who developed AKI. Conclusions Patients who had AKI were older, had higher BMI with higher preoperative CRP levels, more frequent distant organ metastasis, longer operation times, and higher amounts of blood transfused intraoperatively. Defining preoperative, intraoperative, and postoperative risk factors for postoperative AKI and taking necessary precautions are important for the early detection and intervention of AKI.

Cardiometabolic disease and obesity patterns differentially predict acute kidney injury after total joint replacement: a retrospective analysis

BACKGROUND

Acute kidney injury (AKI) is a frequent yet understudied postoperative total joint arthroplasty complication. This study aimed to describe cardiometabolic disease co-occurrence using latent class analysis, and associated postoperative AKI risk.

METHODS

This retrospective analysis examined patients ≥18 years old undergoing primary total knee or hip arthroplasties within the US Multicenter Perioperative Outcomes Group of hospitals from 2008 to 2019. AKI was defined using modified Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Latent classes were constructed from eight cardiometabolic diseases including hypertension, diabetes, and coronary artery disease, excluding obesity. A mixed-effects logistic regression model was constructed for the outcome of any AKI and the exposure of interaction between latent class and obesity status adjusting for preoperative and intraoperative covariates.

RESULTS

Of 81 639 cases, 4007 (4.9%) developed AKI. Patients with AKI were more commonly older and non-Hispanic Black, with more significant comorbidity. A latent class model selected three groups of cardiometabolic patterning, labelled 'hypertension only' (n=37 223), 'metabolic syndrome (MetS)' (n=36 503), and 'MetS+cardiovascular disease (CVD)' (n=7913). After adjustment, latent class/obesity interaction groups had differential risk of AKI compared with those in 'hypertension only'/non-obese. Those 'hypertension only'/obese had 1.7-fold increased odds of AKI (95% confidence interval [CI]: 1.5-2.0). Compared with 'hypertension only'/non-obese, those 'MetS+CVD'/obese had the highest odds of AKI (odds ratio 3.1, 95% CI: 2.6-3.7), whereas 'MetS+CVD'/non-obese had 2.2 times the odds of AKI (95% CI: 1.8-2.7; model area under the curve 0.76).

CONCLUSIONS

The risk of postoperative AKI varies widely between patients. The current study suggests that the co-occurrence of metabolic conditions (diabetes mellitus, hypertension), with or without obesity, is a more important risk factor for acute kidney injury than individual comorbid diseases.

Comparing five equations to calculate estimated glomerular filtration rate to predict acute kidney injury following total joint arthroplasty

BACKGROUND

Acute kidney injury (AKI) following total joint arthroplasty (TJA) is associated with increased morbidity and mortality. Estimated glomerular filtration rate (eGFR) is used as an indicator of renal function. The purpose of this study was (1) to assess each of the five equations that are used in calculating eGFR, and (2) to evaluate which equation may best predict AKI in patients following TJA.

METHODS

The National Surgical Quality Improvement Program (NSQIP) was queried for all 497,261 cases of TJA performed from 2012 to 2019 with complete data. The Modification of Diet in Renal Disease (MDRD) II, re-expressed MDRD II, Cockcroft-Gault, Mayo quadratic, and Chronic Kidney Disease Epidemiology Collaboration equations were used to calculate preoperative eGFR. Two cohorts were created based on the development of postoperative AKI and were compared based on demographic and preoperative factors. Multivariate regression analysis was used to assess for independent associations between preoperative eGFR and postoperative renal failure for each equation. The Akaike information criterion (AIC) was used to evaluate predictive ability of the five equations.

RESULTS

Seven hundred seventy-seven (0.16%) patients experienced AKI after TJA. The Cockcroft-Gault equation yielded the highest mean eGFR (98.6 ± 32.7), while the Re-expressed MDRD II equation yielded the lowest mean eGFR (75.1 ± 28.8). Multivariate regression analysis demonstrated that a decrease in preoperative eGFR was independently associated with an increased risk of developing postoperative AKI in all five equations. The AIC was the lowest in the Mayo equation.

CONCLUSIONS

Preoperative decrease in eGFR was independently associated with increased risk of postoperative AKI in all five equations. The Mayo equation was most predictive of the development of postoperative AKI following TJA. The mayo equation best identified patients with the highest risk of postoperative AKI, which may help providers make decisions on perioperative management in these patients.

Obese elderly patients with hip fractures may have better survival outcomes after surgery

BACKGROUND

In recent years, there has been an increasing amount of research on the "obesity paradox". So our primary objective was to explore whether this phenomenon exists in our study, and secondary objective was to determine the effect of body mass index (BMI) on major complications, and the incidence of acute kidney injury (AKI) after hip fracture surgery after controlling for confounding factors.

METHODS

We included patients over 70 years old with hip fracture who were admitted to the Department of Orthopedics, Peking University First Hospital between 2015 and 2021. Patients were classified as underweight (UW, < 18.5 kg/m²), normal weight (NW, 18.5-24.9 kg/m²), overweight (OW, 25.0-29.9 kg/m²) and obese (OB, ≥ 30.0 kg/m²). We analyzed demographic characteristics, operation information and postoperative outcomes. Using multivariate regression with normal-weight patients as the reference, we determined the odds of 1-year mortality, major complications, and AKI by BMI category.

RESULTS

A total of 644 patients were included. Nine percent of patients died after 1 year, 18% had major postoperative complications, and 12% had AKI. There was a U-shaped relationship between BMI and the rates of major complications or AKI. However, there was a linear decreasing relationship between 1-year mortality and BMI. After controlling for confounding factors, multivariate regression analysis showed that the risk of 1-year mortality after surgery was 2.24 times higher in underweight patients than in normal-weight patients (P < 0.05, OR: 2.24, 95% CI 1.14-4.42). Compared with normal-weight patients, underweight patients had a 2.07 times increased risk of major complications (P < 0.05, OR 2.07, 95% CI 1.21-3.55), and the risk of major complications in obese patients was 2.57 times higher than that in normal-weight patients (P < 0.05, OR 2.57, 95% CI 1.09-6.09). Compared with normal-weight, underweight patients had a 2.18 times increased risk of AKI (P < 0.05, OR 2.18, 95% CI 1.17-4.05).

CONCLUSIONS

The 1-year mortality risk of patients with higher BMI was significantly reduced. Besides, compared with normal-weight patients, underweight patients and obese patients have a higher risk of major complications; low-weight and obese patients are at higher risk for AKI.

Improving Postoperative Acute Kidney Injury Rates Following Primary Total Joint Arthroplasty

BACKGROUND

Perioperative hip and knee arthroplasty complications remain a significant clinical and financial burden. Our institution has shifted to developing protocols to decrease these perioperative complications. This study focuses on acute kidney injury (AKI) rate status post primary total joint arthroplasty (TJA). Current literature demonstrates a 2%-15% incidence of AKI following TJA. However, there is a paucity of published literature on protocols that have effectively reduced AKI rates following TJA. The purpose of this study is to evaluate the effect that our institutionally developed perioperative renal protocol had on the postoperative AKI rates.

METHODS

A retrospective cohort study was performed. Patient demographics, baseline creatinine, and postoperative creatinine values during the patient's hospitalization were collected and analyzed. The preintervention cohort data contained all patients at our institution who underwent a primary TJA from November 1, 2016 to January 1, 2018. The postintervention cohort included all primary TJA patients from July 1, 2018 to February 2, 2020. AKI was defined using the AKI Network classification system comparing baseline and postoperative creatinine values. A multivariate analysis was performed to determine the statistical significance of our results.

RESULTS

Before intervention 1013 patients underwent a primary TJA with 68 patients developing an AKI postoperatively. After intervention 2169 patients underwent primary TJA with 90 patients developing an AKI (6.71% vs 4.15%; P = .0015, odds ratio = 0.59, 95% confidence interval = 0.42-0.82).

CONCLUSION

This study demonstrated that implementation of a perioperative renal protocol can significantly reduce AKI rates. A reduction in AKI rates following TJA will result in improved outcomes and secondarily decrease the financial impact of postoperative complications seen following TJA.

Threshold heterogeneity of perioperative hemoglobin drop for acute kidney injury after noncardiac surgery: a propensity score weighting analysis

Background

Perioperative hemoglobin drop after noncardiac surgery is associated with acute kidney injury (AKI). However, opinion on the tolerable difference in postoperative hemoglobin drop in patients with different preoperative hemoglobin levels does not reach a consensus. This study aimed to identify hemoglobin drop thresholds for AKI after noncardiac surgery stratified by preoperative hemoglobin levels.

Method

This was a single-center retrospective cohort study for elective noncardiac surgery from January 1, 2012, to December 31, 2018. The endpoint was the occurrence of AKI 7 days postoperatively in the hospital. The generalized additive model described the non-linear relationship between hemoglobin drop and AKI occurrence. The minimum P-value approach identified cut-off points of hemoglobin drop within postoperative 7 days for patients with or without preoperative anemia. Stratified by preoperative anemia, hemoglobin drop’s odds ratio as continuous, quintile and dichotomous variables by various cut-off points for postoperative AKI were calculated in multivariate logistic regression models before and after propensity score weighting (PSW).

Results

Of the 35,631 surgery, 5.9% (2105 cases) suffered postoperative AKI. Non-linearity was found between hemoglobin drop and postoperative AKI occurrence. The thresholds and corresponding odds ratio of perioperative hemoglobin drop for patients with and without preoperative anemia were 18 g/L (1.38 (95%CI 1.14 -1.62), P < .001; after PSW: 1.42 (95%CI 1.17 -1.74), P < .001) and 43 g/L (1.81 (95%CI 1.35—2.27), P < .001; after PSW: 2.88 (95%CI 1.85—4.50), P < .001) respectively. Overall thresholds and corresponding odds ratio were 43 g/L (1.82 (95%CI 1.42—2.21)), P < .001; after PSW: 3.29 (95%CI 2.00—5.40), P < .001). Sensitivity analysis showed similar results. Heterogeneity subgroup analysis showed that intraoperatively female patients undergoing intraperitoneal surgery without colloid infusion seemed to be more vulnerable to higher hemoglobin drop. Further analysis showed a possible linear relationship between preoperative hemoglobin and perioperative hemoglobin drop thresholds. Additionally, this study found that the creatinine level changed simultaneously with hemoglobin level within five postoperative days.

Conclusions

Heterogeneity of hemoglobin drop endurability exists after noncardiac non-kidney surgery. More care and earlier intervention should be put on patients with preoperative anemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02834-3.

Incidence and risk factors for acute kidney injury after total joint arthroplasty

BACKGROUND

Acute kidney injury (AKI) is one of the most common medical causes for readmission following total joint arthroplasty (TJA). This study aimed to (1) examine whether the incidence of AKI has changed over the past decade with the adoption of modern perioperative care pathways and (2) identify the risk factors and concomitant adverse events (AEs) associated with AKI.

METHODS

535,291 primary TJA procedures from the American College of Surgeons National Surgical Quality Improvement Program from 2011 to 2018 were retrospectively reviewed. The annual incidence of AKI was analyzed for significant changes over time. Matched cohort analyses were performed to identify the risk factors and AEs associated with AKI using multivariate logistic regression.

RESULTS

The mean incidence of AKI was 0.051%, which remained unchanged during the study period (P = 0.121). Factors associated with AKI were diabetes (OR 1.96, P = 0.009), bilateral procedure (OR 6.93, P = 0.030), lower preoperative hematocrit level (OR 1.09, P = 0.015), body mass index (OR 1.04, P = 0.025), and higher preoperative BUN (OR 1.03, P = 0.043). AKI was associated with length of stay (LOS) > 2 days (OR 4.73, P <  0.001), non-home discharge (OR 0.25, P <  0.001), 30-day readmission (OR 12.29, P <  0.001), and mortality (OR 130.7, P <  0.001).

CONCLUSIONS

The incidence of AKI has not changed over the past decade, and it remains a major bundle buster resulting in greater LOS, non-home discharge, readmissions, and mortality. Avoidance of bilateral TJA in patients with DM and high BMI as well as preoperative optimization of anemia and BUN levels are advised.

Application of Machine Learning Algorithms to Predict Acute Kidney Injury in Elderly Orthopedic Postoperative Patients

Objective

There has been a worldwide increment in acute kidney injury (AKI) incidence among elderly orthopedic operative patients. The AKI prediction model provides patients’ early detection a possibility at risk of AKI; most of the AKI prediction models derive, however, from the cardiothoracic operation. The purpose of this study is to predict the risk of AKI in elderly patients after orthopedic surgery based on machine learning algorithm models.

Methods

We organized a retrospective study being comprised of 1000 patients with postoperative AKI undergoing orthopedic surgery from September 2016, to June, 2021. They were divided into training (80%;n=799) and test (20%;n=201) sets.We utilized nine machine learning (ML) algorithms and used intraoperative information and preoperative clinical features to acquire models to predict AKI. The performance of the model was evaluated according to the area under the receiver operating characteristic (AUC), sensitivity, specificity and accuracy. Select the optimal model and establish the nomogram to make the prediction model visualization. The concordance statistic (C-statistic) and calibration curve were used to discriminate and calibrate the nomogram respectively.

Results

In predicting AKI, nine ML algorithms posted AUC of 0.656–1.000 in the training cohort, with the randomforest standing out and AUC of 0.674–0.821 in the test cohort, with the logistic regression model standing out. Thus, we applied the logistic regression model to establish nomogram. The nomogram was comprised of ten variables: age, body mass index, American Society of Anesthesiologists, hypoproteinemia, hypertension, diabetes, anemia, duration of low mean arterial pressure, mean arterial pressure, transfusion.The calibration curves showed good agreement between prediction and observation in both the training and test sets.

Conclusion

By including intraoperative and preoperative risk factors, ML algorithm can predict AKI and logistic regression model performing the best. Our prediction model and nomogram that are based on this ML algorithm can help lead decision-making for strategies to inhibit AKI over the perioperative duration.

Preventing Acute Kidney Injury and Hypotension After Elective Total Joint Arthroplasty Is Possible: An Update to an Established Multidisciplinary Protocol

INTRODUCTION

Based on preoperative and perioperative risk factors that have been found to correlate with the development of acute kidney injury (AKI), our institution developed a protocol aimed at managing and improving outcomes in all elective THA and TKA patients. This article highlights the continued success and growth of our protocol aimed at decreasing AKI and hypotension in elective total joint arthroplasty patients.

METHOD

A multidisciplinary team comprising orthopaedic surgeons, nephrologists, anesthesiologists, cardiologists, and internal medicine hospitalists created a comprehensive protocol aimed at decreasing complications after elective joint arthroplasty and improving clinical outcomes across multiple hospitals. Patient demographics, hospital length of stay, readmission rates, mortality, and postoperative AKI and hypotension incidences were recorded and compared between preprotocol phase I (initial protocol implementation) and phase II (protocol expansion across 10 hospitals) patient cohorts.

RESULTS

Overall, 3,222 patients over 56 months and 10 hospitals were included. Our phase II AKI rate (0.6%) was significantly lower than our preprotocol rate (6.2%, P < 0.01) and statistically similar to our phase I rate (1.2%, P = 0.61). Our hypotension rate in phase II (6.8%) was significantly lower than our preprotocol rate (12.7%, P < 0.01) but statistically similar to our phase I rate (5.9%, P = 0.40). Furthermore, a significant decrease was observed in hospital length of stay (P < 0.01) over time, but no difference was observed in readmission (P = 0.59) and mortality rates (P = 1.00) over time.

DISCUSSION

This protocol-driven interventional study provides a detailed and successful multidisciplinary method to manage and decrease rates of AKI and hypotension in a large patient cohort across multiple hospital centers.

Staggered bilateral total knee arthroplasty during a single hospitalization: is it still an option? a systematic review

BACKGROUND

Bilateral knee osteoarthritis requiring total knee arthroplasty (TKA) can be addressed simultaneously in one surgical setting, staggered a few days apart during a single hospitalization, or staged several weeks to months apart. Several studies have reported on the complications and clinical outcomes of staggered bilateral TKA (BTKA) in a single hospitalization. However, there is no consensus regarding the safety and efficacy of this practice.

MATERIALS AND METHODS

We performed a systematic review of the literature, utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and identifying articles that reported the clinical outcomes and postoperative complications following staggered BTKA.

RESULTS

Overall, six articles were included for analysis, including 43,892 patients in total. Females (n = 25,931; 59% of all patients) outnumbered males (n = 17,961; 40.1% of all patients), and most patients were middle-aged or elderly (mean age: 68.0 years). The majority of studies (83%) used a 1-week interval as the maximum time for single-hospitalization staggered BTKA. Five studies (83%) reported no difference in mortality rates between staggered, simultaneous, or staged BTKA. Compared to staged BTKA, staggered BTKA conferred an increased rate of blood transfusions. There was no consensus that staggered BTKA led to reduced complications rates, compared to simultaneous or staged BTKA.

CONCLUSIONS

Single-hospitalization staggered BTKA does not appear to be safer than the well-established simultaneous or staged procedures. Overall, the data suggest that staggered BTKA will continue to decline in utilization, as staggered BTKA does not appear to yield clinical advantage over simultaneous BTKA in a medically appropriate patient. LEVEL OF EVIDENCE III: systematic review (lowest level of studies included).

Risk Factors and Effect of Acute Kidney Injury on Outcomes Following Total Hip and Knee Arthroplasty

BACKGROUND

Development of acute kidney injury (AKI) following primary total joint arthroplasty (TJA) is a potentially avoidable complication associated with negative outcomes including discharge to facilities and mortality. Few studies have identified modifiable risk factors or strategies that the surgeon may use to reduce this risk.

METHODS

We identified all patients undergoing primary TJA at a single hospital from 2005 to 2017, and collected patient demographics, comorbidities, short-term outcomes, as well as perioperative laboratory results. We defined AKI as an increase in creatinine levels by 50% or 0.3 points. We compared demographics, comorbidities, and outcomes between patients who developed AKI and those who did not. Multivariate regressions identified the independent effect of AKI on outcomes. A stochastic gradient boosting model was constructed to predict AKI.

RESULTS

In total, 814 (3.9%) of 20,800 patients developed AKI. AKI independently increased length of stay by 0.26 days (95% confidence interval [CI] 0.14-0.38, P < .001), in-hospital complication risk (odds ratio = 1.73, 95% CI 1.45-2.07, P < .001), and discharge to facility risk (odds ratio = 1.26, 95% CI 1.05-1.53, P = .012). Forty-one predictive variables were included in the predictive model, with important potentially modifiable variables including body mass index, perioperative hemoglobin levels, surgery duration, and operative fluids administered. The final predictive model demonstrated excellent performance with a c-statistic of 0.967.

CONCLUSION

Our results confirm that AKI has adverse effects on outcome metrics including length of stay, discharge, and complications. Although many risk factors are nonmodifiable, maintaining adequate renal perfusion through optimizing preoperative hemoglobin, sufficient fluid resuscitation, and reducing blood loss, such as through the use of tranexamic acid, may aid in mitigating this risk.

Determining the risk of acute kidney injury in patients who underwent total joint replacement: A retrospective study

OBJECTIVES

Total joint replacement (TJR) is a commonly performed procedure worldwide, and postoperative acute kidney injury (AKI) is one of the complications that determine the overall prognosis in various surgical settings. We aimed to identify the risk of AKI after TJR (primary and revision) and determine the factors associated with postoperative AKI.

METHODS

We performed a retrospective study of 1068 patients (>18 years) who underwent TJR between 2014 and 2019 at a tertiary medical center. Patients' demographic, clinical, and laboratory data were reviewed.

RESULTS

A total of 1068 patients were included in this study [mean age, 60.5 ± 13 years; 260 men (24.3%); 808 women (75.7%)]. A total of 962 patients (90.1%) underwent primary joint replacement (PJR) and 106 underwent joint revision (9.9%). Sixty-six patients (6.2%) had postoperative AKI. Primary total hip replacement patients had a lower risk of AKI than patients with other types of TJR (3.0%; p = 0.024). The factors associated with AKI (adjusting for known confounders) included male gender [adjusted odds ratio (AOR): 1.751; 95% confidence interval (CI): 1.01-3.03; p = 0.046], diabetes mellitus (DM) [AOR: 2.806; 95% CI: 1.687-5.023; p ≤ 0.001], hypertension (HTN) [AOR: 1.751; 95% CI: 1.159-3.442; p = 0.013], and the use of vancomycin as a prophylactic antibiotic [AOR: 1.691; 95% CI: 1.1-2.913; p = 0.050]. Chronic kidney disease (CKD) [AOR: 1.00; 95% CI: 0.432-2.27; p = 0.981] was not found to be a significant risk factor.

CONCLUSION

In this study, the risk of preoperative AKI in patients who underwent TJR was 6.2%. Male gender, preoperative comorbidities such as DM and HTN, and preoperative use of vancomycin were associated with increased risk of postoperative AKI.

Acute Deterioration of Kidney Function after Total Hip Arthroplasty

Introduction:

Post-operative acute kidney injury is a serious complication and identifying modifiable factors could assist in peri-operative management. This study aimed to identify the pre-operative and intra-operative factors associated with the incidence of post-operative acute kidney injury and acute deterioration of kidney function after total hip arthroplasty.

Materials and methods: This single-center, retrospective, observational study included 203 patients who underwent unilateral primary total hip arthroplasty. Acute kidney injury was determined using biochemical markers according to the risk, injury, failure, loss of kidney function, and end-stage kidney disease (RIFLE) criteria. Acute deterioration of kidney function was defined as the reduction of estimated glomerular filtration rate by ≥10ml/min/1.73m².

Results:

Prior to total hip arthroplasty, 20% of all patients met the chronic renal dysfunction criterion of glomerular filtration rates <60ml/min/1.73m² (glomerular filtration rate categories G3a-G5). Incidence rates of acute kidney injury and acute deterioration of kidney function after total hip arthroplasty were 0.49% and 6.9%, respectively. Multivariate regression analysis showed that diabetes mellitus and use of nonsteroidal anti-inflammatory drugs before total hip arthroplasty were significant risk factors for acute deterioration of kidney function. Advanced age, preoperative renal dysfunction, antihypertensive, diuretics, or statin use, operation time, total blood loss, type of anesthetic, and body mass index were not significant risk factors.

Conclusion:

Diabetes mellitus and use of nonsteroidal anti-inflammatory drugs were controllable risks, and multidisciplinary approaches are a reasonable means of minimising peri-operative acute kidney injury or acute deterioration of kidney function.

Occurrence and predictive factors of acute renal injury following hip and knee arthroplasty

BACKGROUND

To analyze the incidence of early acute kidney injury (AKI) and perioperative factors following hip and knee joint replacement.

METHODS

A total of 6281 patients from the department of orthopedics from January 2016 to July 2018 were enrolled, and 1490 patients undergoing hip and knee arthroplasty met the inclusion criteria. The preoperative, intraoperative and postoperative parameters were recorded. The retrospective cohort study was carried out to analyze predictors for AKI and postoperative creatinine elevation following hip and knee joint replacement.

RESULTS

Eighty patients (5.4%) met AKI criteria. Age, American Society of Anesthesiologists (ASA) physical status and preoperative diabetes were identified as independent predictors for postoperative AKI in patients undergoing hip and knee arthroplasty (p < 0.05). Age, male, preoperative diabetes, hypertension, and preoperative creatinine were identified as independent predictors for postoperative creatinine elevation (p < 0.05). Patients with AKI were more likely to enter the ICU than non-AKI patients (25% vs 5.6%, p < 0.05). Compared with non-AKI patients, the total hospital stay (16 [11-22] vs 13 [10-16] days) and postoperative hospital stay (11 [8-14] vs 8 [7-11] days) for AKI patients were significantly prolonged (p < 0.05).

CONCLUSION

The study shows age, male, preoperative diabetes, hypertension, and preoperative creatinine were independent predictors for postoperative creatinine elevation. In addition, age, ASA physical status and preoperative diabetes are independent predictors for postoperative AKI in patients undergoing hip and knee joint replacement. Postoperative AKI seems to increase ICU admission and significantly prolonged hospital stay.

Incidence and risk factors of acute kidney injury after total joint arthroplasty; a retrospective cohort study

BACKGROUND

Acute Kidney Injury (AKI) is a common complication post-arthroplasty, although it has not been extensively studied. We carried out a retrospective study to determine the incidence and risk factors of AKI in patients undergoing total joint arthroplasty (TJA).

METHOD

We reviewed the medical records of all patients who underwent elective TJA from December 2014 to January 2017 at the Salford Royal Hospital, UK. AKI was defined using the AKIN, RIFLE and KDIGO criteria in patients with worsened renal function post-arthroplasty. We analysed the association of the demographics, risk factors, medications and use of peri-operative IV fluids with AKI. A logistic regression was performed to find any correlation between these factors and incidence of AKI.

RESULTS

197 patients were included in our study, the mean age was 70.2 and male to female ratio was 6:5. Of these, 32(16.2%) developed an AKI. The multivariate logistic regression revealed 4 independent factors associated with the risk of AKI; age (P = 0.0011, OR 1.07, 95% CI 1.03-1.18), obesity (P = 0.003, OR 6.4, 95% CI 2.34-17.5), smoking (P = 0.0482, OR 3.76, 95% CI 1.01-14.0) and COPD (P = 0.0253, OR 3.85, 95% CI 1.18-12.5).

CONCLUSION

The incidence of AKI post-arthroplasty was found to be much higher than stated in other literatures. The recognition of the high incidence and multiple independent risk factors will allow a better approach to peri-operative management, limiting the risks of AKI. Our study also highlighted the importance of documenting urine output and the need to repeat the renal function test 3 months after an AKI to assess recovery.

Acute Kidney Injury in Subjects With Chronic Kidney Disease Undergoing Total Joint Arthroplasty

BACKGROUND

Chronic kidney disease (CKD) has been associated with higher incidence of complications after total joint arthroplasty (TJA) but the incidence, risk factors and outcomes of acute kidney injury (AKI) in this setting remains insufficiently understood.

METHODS

We assessed the impact of baseline CKD on the risk of developing AKI after TJA performed between 1/2012 and 12/2016 in a single-center, retrospective cohort study. CKD was defined by estimated glomerular filtration rate <60 mL/min/1.73 m² on 2 separate occasions within 3 months prior TJA. AKI was defined using a modified Kidney Disease: Improving Global Outcomes criteria based on serum creatinine (sCr) only to assess the severity of AKI. Complete AKI recovery was defined as the lowest post-AKI sCr within 20% of pre-AKI sCr values and partial recovery if within 30%, all within 90 days after TJA.

RESULTS

Twenty-four percent of the 1,212 subjects undergoing TJA had pre-existing CKD. The overall incidence of AKI in the CKD subjects was 30%; of these, 55% had stage-1 AKI, 1% had stage-2 AKI and 44% had stage-3 AKI. AKI was more common in African Americans, those with diabetes or heart failure, requiring perioperative transfusions or receiving diuretics before surgery. While 82% of the AKI subjects achieved complete recovery of kidney function, 4% had only partial recovery and 14% did not reach a post-AKI sCr level within 30% of pre-AKI values. The incidence (P < 0.001) but not the severity (P = 0.202) of AKI correlated with stages of baseline CKD.

CONCLUSIONS

The presence of CKD was associated with a high incidence of AKI after TJA. In these subjects, more than half the cases of AKI were of mild degree and had a favorable outcome. However, 18% of them did not have complete recovery of kidney function. Stages of baseline CKD were associated with increased incidence but not severity of AKI after TJA.

Acute Kidney Injury in Patients Undergoing Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

Background: The number of total hip arthroplasties (THA) performed across the world is growing rapidly. We performed this meta-analysis to evaluate the incidence of acute kidney injury (AKI) in patients undergoing THA. Methods: A literature search was performed using MEDLINE, EMBASE and Cochrane Database from inception until July 2018 to identify studies assessing the incidence of AKI (using standard AKI definitions of RIFLE, AKIN, and KDIGO classifications) in patients undergoing THA. We applied a random-effects model to estimate the incidence of AKI. The protocol for this meta-analysis is registered with PROSPERO (no. CRD42018101928). Results: Seventeen cohort studies with a total of 24,158 patients undergoing THA were enrolled. Overall, the pooled estimated incidence rates of AKI and severe AKI requiring dialysis following THA were 6.3% (95% CI: 3.8%–10.2%) and 0.5% (95% CI: 0.1%–2.3%). Subgroup analysis based on the countries by continent was performed and demonstrated the pooled estimated incidence of AKI following THA of 9.2% (95% CI: 5.6%–14.8%) in Asia, 8.1% (95% CI: 4.9%–13.2%) in Australia, 7.4% (95% CI: 3.2%–16.3%) in Europe, and 2.8% (95% CI: 1.2%–17.0%) in North America. Meta-regression of all included studies showed significant negative correlation between incidence of AKI following THA and study year (slope = −0.37, p <0.001). There was no publication bias as assessed by the funnel plot and Egger’s regression asymmetry test with p = 0.13 for the incidence of AKI in patients undergoing THA. Conclusion: The overall estimated incidence rates of AKI and severe AKI requiring dialysis in patients undergoing THA are 6.3% and 0.5%, respectively. There has been potential improvement in AKI incidence for patients undergoing THA over time.

Acute Kidney Injury Following Failed Total Hip and Knee Arthroplasty

BACKGROUND

Acute kidney injury (AKI) can complicate primary total joint arthroplasty (TJA) of the hip and knee, although the incidence of AKI following revision TJA including prosthetic joint infection (PJI) is poorly defined. We assessed the incidence and risk factors for AKI following revision TJA including surgical treatment of PJI with placement of an antibiotic-loaded cement (ALC) spacer.

METHODS

We retrospectively reviewed 3218 consecutive failed TJAs. Patients with aseptic failure were compared to those with PJI. AKI was determined by RIFLE creatinine criteria. PJIs treated with placement of ALC were compared to PJIs without. Risk factors for AKI were determined by multivariable analysis within the whole group and within those with PJI.

RESULTS

AKI developed in 3.4% of 2147 patients revised for aseptic reasons and in 45% of 281 with PJI, including 29% of 197 receiving an ALC and 82% of 84 patients treated with other procedures. By multivariable analysis, age, surgery for PJI, total number of surgeries, and estimated GFR 60-90 compared to >90 cc/min/1.73 m² were significantly associated with AKI in the whole cohort. Among PJI patients, age, Charlson comorbidity index, and reimplantation surgery were associated with AKI by multivariable analysis. No differences were found between patients with PJI treated with or without ALC. No modifiable factors were found.

CONCLUSION

AKI develops following aseptic revision TJA at a rate similar to primary TJA, but at a significantly higher rate following surgery for PJI with or without placement of ALC.

Novel renal markers for the assessment of renal integrity in patients undergoing knee arthroplasty - a pilot study

Background

The feasibility of novel kidney injury biomarkers in consecutive patients having total knee arthroplasty with local infiltration analgesia was evaluated.

Methods

We enrolled 30 patients scheduled for elective unilateral total knee arthroplasty. Paired plasma and urine samples were taken before surgery and at 4 h, 24 h and 48 h after surgery to measure creatinine, cystatin C, neutrophil gelatinase associated lipocalin, kidney injury molecule-1, interleukin-18 and liver-type fatty acid-binding protein.

Results

At baseline, 13 subjects had normal kidney function, 15 had mild and two had moderate kidney failure evaluated by calculated glomerular filtration rate. None of the subjects had all measured novel renal markers below proposed cut-off concentrations. Altogether 28/30 subjects had one (n = 3), two (n = 7) or three (n = 18) plasma neutrophil gelatinase associated lipocalin values above normal. In seven of these 28 subjects plasma creatinine, calculated glomerular filtration rate and plasma cystatin C were within the reference values. Five subjects had a low urine output, < 0.5 mL/h, indicating transient acute kidney injury, four of these had high plasma neutrophil gelatinase associated lipocalin and one high plasma cystatin C.

Conclusions

In the present study plasma neutrophil gelatinase associated lipocalin was elevated in most subjects with total knee arthroplasty and local infiltration analgesia as a marker of possible renal proximal tubular injury. Five subjects had transient low urine output, but none developed renal deterioration requiring treatment.

Staggered Rather Than Staged or Simultaneous Surgical Strategy May Reduce the Risk of Acute Kidney Injury in Patients Undergoing Bilateral TKA

BACKGROUND

The strategy for bilateral total knee arthroplasty (TKA) depends on the timing of surgery for each knee. The purpose of this study was to determine whether the type of surgical strategy for bilateral TKA (staggered, staged, or simultaneous) influences the incidence of acute kidney injury (AKI) and related complications.

METHODS

Enrolled patients from a single tertiary teaching hospital were divided into 3 groups according to the surgical strategy for bilateral TKA: staggered (≤7 days between the first and second procedure; n = 368), staged (8 days to 1 year between the first and second procedure; n = 265), or simultaneous (n = 820). The incidence of AKI as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria was assessed. The rates of major postoperative complications, major adverse cardiovascular and cerebral events, intensive care unit (ICU) admissions, and mortality were also evaluated. To reduce the influence of possible confounding factors, inverse probability of treatment weighting based on propensity-score analysis was used.

RESULTS

The primary outcome was the incidence of AKI according to surgical strategy. The staggered group had a lower rate of AKI compared with the other 2 groups (p < 0.001): 2.4% (9 of 368 patients), 6.0% (16 of 265), and 11.2% (92 of 820) in the staggered, staged, and simultaneous groups, respectively.

CONCLUSIONS

The type of bilateral TKA strategy was an independent risk factor for the development of AKI. The assessment of additional risk factors for the development of AKI is essential before deciding on surgical strategy.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Incidence and Risk Factors of Acute Kidney Disease after Total Knee Arthroplasty with Early Postoperative Volume Supplement

Background

Etiology of acute kidney disease (AKD) after total knee arthroplasty (TKA) was considered as multifactorial. However, the role of early postoperative volume supplement in AKD rate has not been investigated. The purpose of this study was to evaluate the incidence and risk factors of AKD in patients with early volume supplement following TKA.

Methods

This was a retrospective study with 458 patients who underwent unilateral TKA. All the patients received 6% tetrastarch, 7.5ml/kg, early in the postoperative period. Postoperative AKD was defined as the postoperative creatinine level ≥ 1.5 times compared with preoperative data. Potential variables associated with AKD were analyzed by multivariate logistic regression model to identify the AKD risk factors in TKA patients after early postoperative volume supplement.

Results

The AKD rate was 3.3% (15 patients) in all patients. Age (OR = 1.09; P = .031) and coronary artery disease (CAD) (OR = 3.63; P = .034) were associated with increased risk of development of postoperative AKD. Other comorbidities as hypertension, diabetes, and CKD were not statistically significant risk factors.

Conclusion

Our study demonstrated that age and CAD were independent risk factors of AKD in TKA patients. However, the common risk factors as hypertension, diabetes, and CKD were not significantly associated with AKD after TKA if early postoperative supplement of tetrastarch is administered.

Reducing Hypotension and Acute Kidney Injury in the Elective Total Joint Arthroplasty Population: A Multi-Disciplinary Approach

BACKGROUND

When critically analyzing our hospital system's rate of hypotension and acute kidney injury (AKI) after total joint arthroplasty, our incidence rates (14.54%, 6.02%) were much higher than our peers (7.17%, 2.03%) and national rates (2.0%, 3.3%). We present a multi-disciplinary management intervention that aimed to decrease overall complication rates.

METHOD

A multi-disciplinary team implemented a protocol at our suburban hospital to limit complication rates after joint replacement surgery. Hypotension, AKI, length of stay (LOS), re-admission rates, and mortality rates were compared before the protocol was implemented, after protocol implementation, and after protocol integration into our EMR (electronic medical record).

RESULTS

In total, 1233 patients over 36 months were followed. Hypotension rates after protocol implementation into EMR (group 3) were significantly lower than rates before the protocol (group 1) (P = .002), with rates after protocol implementation without EMR (group 2) trending toward a significant decrease from group 1 (P = .064). AKI rates in group 3 were significantly lower than group 1 (P = .000) and group 2 (P = .006). No difference was seen in hypotension rates between group 2 and 3 (P = .792) or AKI rates between group 1 and 2 (P = .533). Finally, no significant difference was seen between groups in LOS (P = .560), re-admission rates (P = .378), and mortality rates (all 0.0%).

CONCLUSION

By implementing a comprehensive electronic protocol consisting of pre-operative risk stratification, multi-disciplinary medical optimization, and an evolving post-operative management plan, significant decreases in hypotension and AKI can be seen.

Acute Kidney Disease After Total Hip and Knee Arthroplasty: Incidence and Associated Factors

BACKGROUND

The development of acute kidney disease (AKD) following total joint arthroplasty has not been well characterized in the literature. We sought to calculate the incidence and identify risk factors associated with postoperative AKD for patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

A total of 1000 consecutive cases (860 unique patients, including revisions) of TKA or THA performed between January 2010 and May 2016 were identified. Seventy-nine cases were excluded due to pre-existing kidney dysfunction and 23 additional cases were excluded due to incomplete data, resulting in 898 cases included in the study. There were 492 females and 406 males with a mean age of 58.1 years (range, 14-93 years). The Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease criteria and serum creatinine values were used to determine AKD status. Multiple logistic regression modeling was used to identify postoperative AKD risk factors.

RESULTS

Overall incidence of postoperative AKD was 6.8% (n = 61). Use of perioperative angiotensin receptor blocker (ARBs) or angiotensin-converting enzyme inhibitors (ACEi) (odds ratio [OR] = 2.09; P = .030), increasing body mass index (BMI) (OR = 1.58 per 10 kg/m²; P = .014), and use of vancomycin perioperatively (OR = 1.91; P = .021) were associated with increased odds of development of postoperative AKD.

CONCLUSION

A 6.8% incidence rate of postoperative AKD was noted in patients undergoing TKA or THA. Perioperative use of ARBs/ACEi, perioperative vancomycin use, and increased BMI were associated with increased odds of postoperative AKD.

Risk factors associated with acute kidney injury in a cohort of 20,575 arthroplasty patients

Background and purpose - Patients developing postoperative acute kidney injury (AKI) are at risk of higher morbidity and mortality. In arthroplasty patients, many pre- and perioperative factors are associated with AKI but some of the risk factors are unclear. We report the incidence of postoperative AKI, the conditions associated with it, and survival rates in AKI patients. Patients and methods - We obtained data from 20,575 consecutive hip or knee arthroplasties. Postoperative AKI, occurring within 7 days after the operation, was defined using the risk, injury, failure, loss, and end-stage (RIFLE) criteria. We analyzed independent risk factors for AKI using binary logistic regression. In addition, we reviewed the records of AKI patients and performed a survival analysis. Results - The AKI incidence was 3.3 per 1,000 operations. We found preoperative estimated glomerular filtration rate, ASA classification, body mass index, and duration of operation to be independent risk factors for AKI. Infections, paralytic ileus, and cardiac causes were the predominant underlying conditions, whereas half of all AKI cases occurred without any clear underlying condition. Survival rates were lower in AKI patients. Interpretation - Supporting earlier results, existing renal insufficiency and patient-related characteristics were found to be associated with an increased risk of postoperative AKI. Furthermore, duration of operation was identified as an independent risk factor. We suggest careful renal monitoring postoperatively for patients with these risk factors.

Acute kidney injury following primary hip and knee arthroplasty surgery

Acute kidney injury (AKI) is a recognised postoperative complication following primary hip/knee arthroplasty surgery. The aim of this study was to determine causative and potentially modifiable risk factors associated with postoperative AKI. Standard data were collected for 413 consecutive arthroplasty patients, both retrospectively and prospectively. Univariate and multivariate analyses were performed to identify any potential causative factors. Eight percent of patients developed postoperative AKI. Univariate analysis found increasing age, history of previous chronic kidney disease and requirement for postoperative intravenous fluids to be risk factors for AKI. The multivariate regression analysis model identified age and volume of postoperative fluid prescription as predictive of postoperative AKI. Antibiotic regime and prescription of non-steroidal anti-inflammatory drugs had no significant effect on the risk of AKI. No patients required dialysis but length of stay increased by 50% in the AKI group. Postoperative AKI may result in significant postoperative morbidity and increased length of stay, and may necessitate invasive therapies such as dialysis. Episodes of AKI could also predispose to future similar episodes and are associated with a long-term decrease in baseline renal function. This study has demonstrated that the identified risk factors are generally non-modifiable. Further work is suggested to determine whether targeted interventions in high risk patients would reduce the incidence of AKI.

Stratification and Risk Reduction of Perioperative Acute Kidney Injury

Perioperative acute kidney injury (AKI) is associated with an increased morbidity and mortality. The incidence of AKI varies depending on preoperative risk factors and the surgical setting. Preoperative risk stratification is critical for informed consent and perioperative planning. Perioperative renal protection strategies are potentially invaluable in the prevention of AKI. Current advances in the development of biomarkers may offer the opportunity for early diagnosis and the implementation of therapeutic strategies. Increased awareness and concerted efforts by all perioperative physicians are needed to provide an improved outcome for surgical patients.

Is there a risk of permanent renal dysfunction after primary total hip and knee joint replacements?

Background

Permanent renal dysfunction is considered as being a serious complication which may occur after major surgery and which furthermore may lead to increased morbidity and mortality. The objective of this study was to analyze the incidence of long-term postoperative renal dysfunction after primary total hip and knee joint replacements.

Methods

Long-term postoperative renal dysfunction was analyzed in a retrospective study of 1301 consecutive primary total hip and knee joint replacements performed between January 2009 and December 2013. According to the RIFLE criteria, increased serum creatinine was an indicative of postoperative renal injury. The highest serum creatinine during the first postoperative week was chosen as a sign for maximum acute renal injury and was compared to the highest serum creatinine during the following 4–12 months.

Results

One hundred and forty two patients with an increase in postoperative serum creatinine were included in the follow-up study. Six patients (4.2 %) died due to non-renal causes during the follow-up period. One patient died of severe renal injury, which was relatively very early postoperatively, and another patient had a rise in serum creatinine to 316 μmol/l during the follow-up period. All the remaining 132 patients (94 %) had full recovery with serum creatinine which returned to preoperative levels.

Conclusions

This study did not confirm that patients who underwent primary total hip and knee joint replacement surgery were at risk of developing permanent renal dysfunction up to 1 year after the index surgery.

Greater Wound and Renal Complications in Gout Patients Undergoing Total Joint Arthroplasty

BACKGROUND

Little is known about total joint arthroplasty (TJA) outcomes in gout patients. The purpose of this study was to compare adverse events between gout and nongout patients who underwent primary TJA.

METHODS

Using our institutional database and medical records review, a retrospective case-control study was conducted. From 2000 to 2012, a total of 482 gout TJA patients were matched with nongout TJA patients in a 1:1 ratio. Length of stay, complications, 90-day emergency room visits, and 90-day readmissions in these patients were compared.

RESULTS

Gout patients had greater wound healing problems (12.2% vs 5.0%, P = .001) and renal complications (8.9% vs 3.1%, P = .0003) compared with nongout patients. There were no significant differences between gout and nongout patients in terms of mean length of hospital stay (3.82 vs 3.17 days, P = .11) and 90-day emergency room visits (5.6% vs 3.5%, P = 1.00). Subgroup analysis showed that 90-day readmission rates were higher in gout patients who underwent total hip arthroplasty compared with those in nongout THA patients (6.8% vs 2.1%, P = .02).

CONCLUSION

Gout patients undergoing TJA have greater wound healing problems and renal complications. Surgeons should be cognizant of fluid management, renal monitoring and wound issues and should be cautious when treating TJA gout patients.

Improving acute kidney injury management in lower limb arthroplasty: an educational approach

INTRODUCTION

Acute kidney injury (AKI) is a common but preventable cause of morbidity in elective arthroplasty patients. This study aimed to review the incidence and management of AKI in patients undergoing elective lower limb arthroplasty and compare results to those after the introduction of educational measures to improve prevention, recognition and management of AKI.

METHODS

A retrospective case note review of all patients undergoing elective hip or knee arthroplasty between August and October 2013 was performed. Results were compared to patients treated from February to April 2014, after the introduction of a renal protection protocol, checklist poster and educational sessions. Results were statistically compared using Fisher's exact test.

RESULTS

Two hundred and eleven patients were included in the study: 104 in the initial cohort and 107 in the second cohort. Twenty patients (19.2 %) developed AKI in the initial cohort and 12 patients (11.2 %) in the second (p = 0.13). Recognition, documentation and management of AKI were significantly better following educational sessions and dissemination of posters throughout clinical areas, with 75 % of patients in the second cohort having their AKI documented and treated versus 30 % in the initial cohort.

DISCUSSION/CONCLUSIONS

This quality improvement project has demonstrated the significant impact that simple educational measures can have on improving AKI prevention, recognition and management in patients undergoing elective arthroplasty surgery. The introduction of a logical treatment checklist has been well received by both medical and nursing staff and ensures prompt and efficient management of AKI in a non-specialist area.

Risk of Acute Kidney Injury After Primary and Revision Total Hip Arthroplasty and Total Knee Arthroplasty Using a Multimodal Approach to Perioperative Pain Control Including Ketorolac and Celecoxib

Safe and effective perioperative analgesia is instrumental to patient satisfaction and decreasing LOS after TJA. We evaluated rates of acute kidney injury (AKI) in primary and revision TJA using a multimodal pain control regimen including scheduled celecoxib and PRN ketorolac. Postoperative AKI was identified in 43/903 (4.8%) of 903 of patients with adequate preoperative renal function. Those who developed AKI had significantly increased LOS (P < .01), were older, more obese, and more likely to have diabetes (P < .05). With a protocol incorporating NSAIDs in patients without evidence of preoperative renal impairment, there is a 4.8% rate of AKI, which is 2.7 times higher than the reported literature. Acute postoperative kidney injury was significantly correlated with increased LOS and has important patient safety and healthcare-related cost implications.

Risk factors for renal dysfunction after total hip joint replacement; a retrospective cohort study

Background and purpose of the study

Renal injury and dysfunction are serious complications after major surgery, which may lead to increased morbidity and mortality. The objective of our study was to identify the possible risk factors for renal dysfunction after total hip joint replacement surgery.

Methods

A retrospective study was conducted among 599 consecutive primary hip joint replacements performed between January 2011 and December 2013. According to the RIFLE criteria, increased postoperative serum creatinine was considered indicative of postoperative renal injury. The Welch two-sample test, chi-square test, and Fisher exact test were used for statistical analysis.

Results

Eighty-one patients (13.8 %) had significant moderate or severe postoperative renal dysfunction in which 10 patients (1.7 %) acquired severe and permanent renal impairment.

Conclusion

We identified advanced age, hypertension, general anesthesia, high ASA scores, low intra-operative systolic BP, and prophylactic dicloxacillin as significant risk factors. Low baseline systolic BP, low baseline diastolic blood pressure, and hip fracture diagnosis were independent risk factors for postoperative increase in serum creatinine. Smoking, diabetes mellitus, high BMI, gender, and duration of surgery were not identified as significant risk factors.

Mortality and complications after hip fracture among elderly patients undergoing hemodialysis

BACKGROUND

Osteoporotic hip fractures cause high mortality and morbidity in elderly adults. Compared to the general population, subjects with end-stage renal disease and hemodialysis often develop mineral bone disorders and have a higher risk for hip fractures.

METHODS

We conducted a matched cohort study design and used competing risk analysis to estimate the cumulative incidence of the complication rate. Subjects aged greater than 60 years with hip fracture were selected from Taiwan's National Health Insurance Research Database covering a period from 1997 to 2007, and these subjects were followed up until 2009. We used the Kaplan-Meier method to estimate the overall survival and used the log-rank test and multiple Cox proportional hazards model to explore the risk factors for survival. The cumulative incidence of the first complication was estimated using competing risk analysis.

RESULTS

Among hemodialysis subjects, the three-month, one-year, two-year and five-year mortality rates were 17.3 %, 37.2 %, 51.5 %, and 80.5 %, respectively; the one-year and five-year cumulative incidences of the first surgical complication were 14.2 % and 20.6 %, respectively; and the three-month cumulative incidence of the first medical complication was 24.1 %. Hemodialysis subjects presented a 2.32 times (95 % CI: 2.16-2.49) higher hazard ratio of overall death, 1.15 times (95 % CI: 1.01-1.30) higher sub-hazard ratio (sub-HR) of surgical complications, and 1.35 times (95 % CI: 1.21-1.52) higher sub-HR of the first medical complication than non-hemodialysis controls.

CONCLUSIONS

The overall mortality and complication rates of hemodialysis subjects after surgery for hip fracture were significantly higher than those of non-hemodialysis subjects. Further prospective studies which include important risk factors are necessary to more precisely quantify the adjusted effect of hemodialysis.

Total joint arthroplasty in transplant recipients: in-hospital adverse outcomes

This study aims to determine in-hospital complications and mortality in transplant recipients following total joint arthroplasty. The Nationwide Inpatient Sample database was queried for patients with history of transplant and joint arthroplasty (primary or revision) from 1993 to 2011. Kidney transplant increased risk of surgical site infection (SSI) and wound infections (OR=2.03), systemic infection (OR=2.85), deep venous thrombosis (OR=2.07), acute renal failure (ARF) (OR=3.48), respiratory (OR=1.34), and cardiac (OR=1.21) complications. Liver transplant was associated with SSI/wound infections (OR=2.32), respiratory complications (OR=1.68), cardiac complications (OR=1.34), and ARF (OR=4.48). Other transplants grouped together were associated with wound complications (OR=2.13), respiratory complications (OR=2.06), and ARF (OR=4.42). Our study suggests these patients may be at increased risk of in-hospital complications, particularly ARF in renal and liver transplant patients.

Total joint arthroplasty in cancer patients

Increasing numbers of total joint arthroplasty (TJA) patients have a history, or an active diagnosis, of cancer. We aimed to evaluate the risk of early postoperative complications in these patients. In our series, a history of malignancy was associated with an elevated risk of ischemic cardiac events and postoperative deep vein thrombosis (DVT), while active malignancy was associated with increased respiratory and renal complications, hematoma/seroma formation and early postoperative mortality. Both groups presented increased rates of overall in-hospital complications. Patients with bone metastasis to the hip demonstrated increased DVT and 90-day mortality rates. Cancer patients have increased morbidity and mortality after TJA and should undergo comprehensive medical optimization and adapted thromboprophylaxis.

Perioperative risk factors for acute kidney injury after liver resection surgery: an historical cohort study

PURPOSE

This study aimed to identify the incidence and risk factors for acute kidney injury (AKI) after liver resection surgery and to clarify the relationship between postoperative AKI and outcome.

METHODS

We conducted a historical cohort study of patients who underwent liver resection surgery with sevoflurane anesthesia from January 2004 to October 2011. Acute kidney injury was diagnosed based on the Acute Kidney Injury Network classification within 72 hr after the surgery. Patient data, surgical and anesthetic data, and laboratory data were extracted manually from the patients' electronic charts. Multivariable logistic regression analysis was used to identify perioperative risk factors for postoperative AKI.

RESULTS

Acute kidney injury was diagnosed in 78 of 642 patients (12.1%; 95% confidence interval [CI]: 9.7 to 14.9). Multivariable analysis showed an independent association between postoperative AKI and preoperative estimated glomerular filtration rate (adjusted odds ratio [aOR] 0.74; 95% CI: 0.64 to 0.85), preoperative hypertension (aOR 2.10; 95% CI: 1.11 to 3.97), and intraoperative red blood cell transfusion (aOR 1.04; 95% CI: 1.01 to 1.07). Development of AKI within 72 hr after liver resection surgery was associated with increased hospital mortality, prolonged length of stay, and increased rates of mechanical ventilation, reintubation, and renal replacement therapy.

CONCLUSION

Perioperative risk factors for AKI after liver resection surgery are similar to those established for other surgical procedures. Further studies are needed to establish causality and to determine whether interventions on modifiable risk factors can reduce the incidence of postoperative AKI and improve patient outcome. This study was registered at the University Hospital Medical Information Network (UMIN) Center (UMIN 000008089).

Incidence of acute kidney injury following total joint arthroplasty: a retrospective review by RIFLE criteria

Background

Total joint arthroplasty (TJA) is a common procedure with demand for arthroplasties expected to increase exponentially. Incidence of acute kidney injury (AKI) following TJA is reportedly low, with most studies finding an incidence of <2%, increasing to 9% when emergency orthopaedic patients are included.

Methods

Retrospective medical record review of consecutive primary, elective TJA procedures was undertaken at a large tertiary hospital (Alfred). Demographic, peri-operative and post-operative data were recorded. Factors associated with AKI (based on RIFLE criteria) were determined using multiple logistic regression.

Results

Between January 2011 and June 2013, 425 patients underwent TJA; 252 total knee replacements (TKR) and 173 total hip replacements (THR). Sixty-seven patients (14.8%) developed AKI, including 51 TKR. Factors associated with AKI (adjusting for known confounders) include increasing body mass index [adjusted odds ratio (AOR) 1.14; 95% CI: 1.07, 1.21], older age (AOR 1.07; 95% CI 1.02, 1.13) and lower pre-operative glomerular filtration rate (AOR 0.97; 95% CI 0.96, 0.99) and taking angiotensin-converting enzyme inhibitors (AOR 2.70; 95% CI 1.12, 6.48) and angiotensin-II receptor blockers (AOR 2.64; 95% CI 1.18, 5.93). In most patients, AKI resolved by discharge, however, only 62% of patients had renal function tests after discharge.

Conclusions

This study showed a rate of AKI of nearly 15% in our TJA population, substantially higher than previously reported. Given that AKI and long-term complications are associated, prospective research is needed to further understand the associated factors and predict those at risk of AKI. There may be opportunities to maximize the pre-operative medical management and mitigate risk.

Predictors of acute kidney injury in geriatric patients undergoing total knee replacement surgery

BACKGROUND

Few studies have focused on patients' characteristics that affects acute kidney injury (AKI) after total knee replacement surgery (TKR).

OBJECTIVES

The primary objective of this retrospective study was to identify patients' characteristics associated with AKI after TKR.

PATIENTS AND METHODS

Between January 2008 and December 2009, 659 patients with a mean age of 67.1 years (range, 39-99) underwent TKA at Regional Hospital Knee and Hip Institute. Retrospective chart review was done to identify patients' characteristics that were associated with AKI after TKR. Logistic regression was used to evaluate AKI.

RESULTS

AKI occurred in 21.9% of patients. AKI risk decreased between 2008 and 2009 (odds ratio, 0.55; 95% CI, -0.37 to 0.82) but increased with age (P < 0.001), diabetes mellitus (DM), and angiotensin converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB) use (OR, -1.6; 95% CI, -1.0 to 2.5; and OR, -1.5, 95% CI, -1.0 to 2.3, respectively). However, the effects of DM and ACEI/ARB use were not independent; when both were included in the regression model, neither was statistically significant, and both ORs were smaller than combined OR.

CONCLUSIONS

When examined separately, both DM and preoperative ACEI/ARB use increased the risk of AKI; however these factors were correlated and were not independent predictors of significantly increased risk. Patients with DM have higher tendency to develop AKI and hence, preoperative renal risk stratification should be done in all patients with DM.

Anesthetic technique and acute kidney injury in endovascular abdominal aortic aneurysm repair

OBJECTIVE

Prior studies suggest that general anesthesia (GA) is associated with worse cardiopulmonary outcomes after endovascular abdominal aortic aneurysm repair (EVAR). Patients undergoing EVAR are at a high risk of developing perioperative acute kidney injury (AKI), and the relationship between anesthetic technique and AKI in these patients is not well-characterized. The authors sought to determine if anesthetic technique affected the risk of AKI in patients undergoing EVAR.

DESIGN

Retrospective, observational cohort study analyzed using a multivariate logistic regression model to assess the effects of anesthetic technique on renal outcome.

SETTING

Multiple institutions, mainly in North America.

PARTICIPANTS

Patients in the American College of Surgeons National Surgical Quality Improvement Program from 2005-2010 undergoing EVAR.

INTERVENTIONS

The authors investigated the association between anesthetic techniques, comparing GA to alternative (non-GA) techniques, and AKI.

MEASUREMENTS AND MAIN RESULTS

AKI was defined as an increase in the creatinine level of>2 mg/dL and/or dialysis. Of 13,026 patients, 84.4% underwent GA and 15.6% underwent non-GA techniques. AKI developed in 2.0% of the GA group and 1.4% of the non-GA group (unadjusted odds ratio [OR] 1.43, p = 0.075; adjusted OR [aOR] 1.00, p = 0.99). Risk factors for AKI include ASA class, ruptured aneurysm, preoperative renal dysfunction, symptomatic cardiovascular disease, and perioperative blood transfusion.

CONCLUSIONS

Anesthetic technique is not independently associated with the risk of AKI in patients undergoing EVAR.