The Impact of Kidney Disease on Acute Tubular Necrosis and Surgical Site Infection After Lumbar Fusion

Incidence and predictors of acute kidney injury after elective surgery for lumbar degenerative disease: A 13-year analysis of the US Nationwide Inpatient Sample

BACKGROUND

Acute kidney injury (AKI) is a severe postoperative complication associated with poor clinical outcomes, including the development of chronic kidney disease (CKD) and death. This study aimed to investigate the incidence and determinants of AKI following elective surgeries for degenerative lumbar spine disease.

METHODS

All patient data were extracted from the US Nationwide Inpatient Sample database. After surgery, AKI's incidence and risk factors were identified for lumbar degenerative disease. ICD-9 and ICD-10 codes defined lumbar spine degenerative disease, fusion, decompression, and AKI. The study cohort was categorized by type of surgery, that is, decompression alone or spinal fusion. Regression analysis was used to identify associations between AKI and risk factors organized by surgery type.

RESULTS

The incidence of AKI after decompression or fusion was 1.1% and 1.8%, respectively. However, the incidence of AKI in the United States is rising. The strongest predictor of AKI was underlying CKD, which was associated with an 9.0- to 12.9-fold more significant risk of AKI than in subjects without comorbid CKD. In this setting, older age, congestive heart failure, anemia, obesity, coagulopathy and hospital-acquired infections were also strong predictors of AKI. In contrast, long-term aspirin/anticoagulant usage was associated with lowered AKI risk.

CONCLUSION

Findings of this study inform risk stratification for AKI and may help to optimize treatment decisions and care planning after elective surgery for lumbar degenerative disease.

Incidence of and factors associated with acute kidney injury after scoliosis surgery in pediatric patients

PURPOSE

We sought to identify the national incidence of acute kidney injury (AKI) associated with pediatric posterior spinal fusion (PSF) surgery for scoliosis, and to determine factors that increase risk.

METHODS

The 1998-2014 National Inpatient Sample (NIS), a large United States hospital discharge database, was queried for discharges aged 0-17 years with International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for scoliosis undergoing PSF for the outcome of AKI. Discharges were divided into those with AKI and unaffected. We fit adjusted logistic regression models to yield point estimates, odds ratios, 95% confidence intervals, and p values for the weighted, national population sample with postulated risk factors. The fit of the multivariable regression model was tested using the Hosmer-Lemeshow test, and collinearity using the variance inflation factor.

RESULTS

The NIS contained 103,270 weighted discharges meeting inclusion criteria. AKI incidence was 0.1%. Multivariable logistic regression model showed significantly increased odds ratios with thrombocytopenia, rhabdomyolysis, chronic kidney disease, abnormal coagulation, and male sex. AKI increased both hospital stay and cost by threefold compared to unaffected children.

CONCLUSION

This study suggests that AKI after pediatric PSF is rare. It is associated with abnormal coagulation, chronic kidney disease, and rhabdomyolysis, but not with the number of vertebral levels fused. Female sex appears to be protective. The retrospective nature of study and reliance on ICD-9-CM codes may under-represent the incidence of AKI in pediatric PSF patients.

Postoperative outcomes of kidney transplant recipients undergoing non-transplant-related elective surgery: a systematic review and meta-analysis

Background

Reliable estimates of the absolute and relative risks of postoperative complications in kidney transplant recipients undergoing elective surgery are needed to inform clinical practice. This systematic review and meta-analysis aimed to estimate the odds of both fatal and non-fatal postoperative outcomes in kidney transplant recipients following elective surgery compared to non-transplanted patients.

Methods

Systematic searches were performed through Embase and MEDLINE databases to identify relevant studies from inception to January 2020. Risk of bias was assessed by the Newcastle Ottawa Scale and quality of evidence was summarised in accordance with GRADE methodology (grading of recommendations, assessment, development and evaluation). Random effects meta-analysis was performed to derive summary risk estimates of outcomes. Meta-regression and sensitivity analyses were performed to explore heterogeneity.

Results

Fourteen studies involving 14,427 kidney transplant patients were eligible for inclusion. Kidney transplant recipients had increased odds of postoperative mortality; cardiac surgery (OR 2.2, 95%CI 1.9–2.5), general surgery (OR 2.2, 95% CI 1.3–4.0) compared to non-transplanted patients. The magnitude of the mortality odds was increased in the presence of diabetes mellitus. Acute kidney injury was the most frequently reported non-fatal complication whereby kidney transplant recipients had increased odds compared to their non-transplanted counterparts. The odds for acute kidney injury was highest following orthopaedic surgery (OR 15.3, 95% CI 3.9–59.4). However, there was no difference in the odds of stroke and pneumonia.

Conclusion

Kidney transplant recipients are at increased odds for postoperative mortality and acute kidney injury following elective surgery. This review also highlights the urgent need for further studies to better inform perioperative risk assessment to assist in planning perioperative care.