Does chronic kidney disease affect the mortality rate in patients undergoing spine surgery?

Advanced chronic kidney disease increases complications in anterior cervical discectomies with fusions: An analysis of 75,508 patients

Background

Although anterior cervical discectomy and fusion (ACDF) procedures for cervical spine disease have been increasing amid a growing population of patients with kidney dysfunction, there is a scarcity of literature focusing on kidney dysfunction as a risk-factor for post-operative ACDF complications. The purpose is to evaluate the differential impact of kidney dysfunction on perioperative outcomes including surgical and medical complications, extended length of hospital stay (LOS), and death within 30 days following ACDF.

Patient Sample

This was a retrospective cohort study of prospectively collected data using the American College of Surgeons National Surgical Quality Improvement Program database to identify patients who had undergone an elective ACDF procedure between 2011-2021 using Current Procedural Terminology code 22551. Patients were categorized into five cohorts based on eGFR according to the "Kidney Disease: Improving Global Outcomes" Classification: values of: ≥ 90(reference cohort), 60-89 (G2), 30-59 (G3), 15-29 (G4), and <15 (G5). One-way ANOVA for continuous variables and chi-square tests for categorical variables were used to identify differences in perioperative variables between the five groups. Multivariable logistic regression analysis assessed the effect of kidney dysfunction on post-operative surgical outcomes. Significance was defined as p<.05.

Results

About 75,508 ACDF patients were included, of who 57,480 were G1, 15,186 were G2, 2,192 were G3, 312 were G4, and 338 were G5. G4 and G5 independently increased the risk of medical complications (OR: 1.893, 95% CI [1.296-2.705]; OR: 2.241, 95% CI [1.222-3.964]) and blood transfusion. Only G5 independently increased the risk for extended LOS (OR: 2.410, 95% CI [1.281-4.371], p=.005).

Conclusion

High grade CKD is an independent risk factor for medical complications, extended hospital LOS, and blood transfusions following ACDF, underscoring the importance of risk stratification to optimize perioperative management and reduce the burden of complications and healthcare costs. Conversely, low grade CKD does not increase the risk of complications in ACDF.

American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator as a Predictor of Postoperative Outcomes After Adult Spinal Deformity Surgery: A Retrospective Cohort Analysis

BACKGROUND AND OBJECTIVES

In recent years, there has been an outpouring of scoring systems that were built to predict outcomes after various surgical procedures; however, research validating these studies in spinal surgery is quite limited. In this study, we evaluated the predictability of the American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator (ACS NSQIP SRC) for various postoperative outcomes after spinal deformity surgery.

METHODS

A retrospective chart review was conducted to identify patients who underwent spinal deformity surgery at our hospital between January 1, 2014, and December 31, 2022. Demographic and clinical data necessary to use the ACS NSQIP SRC and postoperative outcomes were collected for these patients. Predictability was analyzed using the area under the curve (AUC) of receiver operating characteristic curves and Brier scores.

RESULTS

Among the 159 study patients, the mean age was 64.5 ± 9.5 years, mean body mass index was 31.9 ± 6.6, and 95 (59.7%) patients were women. The outcome most accurately predicted by the ACS NSQIP SRC was postoperative pneumonia (observed = 5.0% vs predicted = 3.2%, AUC = 0.75, Brier score = 0.05), but its predictability still fell below the acceptable threshold. Other outcomes that were underpredicted by the ACS NSQIP SRC were readmission within 30 days (observed = 13.8% vs predicted = 9.0%, AUC = 0.63, Brier score = 0.12), rate of discharge to nursing home or rehabilitation facilities (observed = 56.0% vs predicted = 46.6%, AUC = 0.59, Brier = 0.26), reoperation (observed 11.9% vs predicted 5.4%, AUC = 0.60, Brier = 0.11), surgical site infection (observed 9.4% vs predicted 3.5%, AUC = 0.61, Brier = 0.05), and any complication (observed 33.3% vs 19%, AUC = 0.65, Brier = 0.23). Predicted and observed length of stay were not significantly associated (β = 0.132, P = .47).

CONCLUSION

The ACS NSQIP SRC is a poor predictor of outcomes after spinal deformity surgery.

Risk of Subsequent Fusion After Isolated Decompression of Lumbar Facet Cysts

INTRODUCTION

Lumbar facet cysts represent a potential source of nerve root compression in elderly patients. Isolated decompression without fusion has proven to be a reasonable treatment option in properly indicated patients. However, the risk of lumbar fusion after isolated decompression and facet cyst excision has yet to be elucidated.

METHODS

The PearlDiver database was reviewed for patients undergoing isolated laminectomy for lumbar facet cyst from January 2015 to December 2018 using Current Procedural Terminology coding. Patients undergoing concomitant fusion or additional decompression, as well as those diagnosed with preexisting spondylolisthesis or without a minimum of 5-year follow-up, were excluded. Rates of subsequent lumbar fusion and potential risk factors for subsequent fusion were identified. Statistical analysis included descriptive statistics, chi square test, and multivariate logistic regression. Results were considered significant at P < 0.05.

RESULTS

In total, 10,707 patients were ultimately included for analysis. At 5-year follow-up, 727 (6.79%) of patients underwent subsequent lumbar fusion after initial isolated decompression. Of these, 301 (2.81% of total patients, 41.4% of fusion patients) underwent fusion within the first year after decompression. Multivariate analysis identified chronic kidney disease, hypertension, and osteoarthritis as risk factors for requiring subsequent lumbar fusion at 5 years following the index decompression procedure ( P < 0.033; all).

CONCLUSION

Patients undergoing isolated decompression for lumbar facet cysts undergo subsequent lumbar fusion at a 5-year rate of 6.79%. Risk factors for subsequent decompression include chronic kidney disease, hypertension, and osteoarthritis. This study will assist spine surgeons in appropriately counseling patients on expected postoperative course and potential risks of isolated decompression.

Preoperative medical assessment for adult spinal deformity surgery: a state-of-the-art review

INTRODUCTION

The purpose of this study is to provide a state-of-the-art review regarding risk factors for perioperative complications in adult spinal deformity (ASD) surgery. The review includes levels of evidence for risk factors associated with complications in ASD surgery.

METHODS

Using the PubMed database, we searched for complications, risk factors, and adult spinal deformity. The included publications were assessed for level of evidence as described in clinical practice guidelines published by the North American Spine Society, with summary statements generated for each risk factor (Bono et al. in Spine J 9:1046-1051, 2009).

RESULTS

Frailty had good evidence (Grade A) as a risk for complications in ASD patients. Fair evidence (Grade B) was assigned for bone quality, smoking, hyperglycemia and diabetes, nutritional status, immunosuppression/steroid use, cardiovascular disease, pulmonary disease, and renal disease. Indeterminate evidence (Grade I) was assigned for pre-operative cognitive function, mental health, social support, and opioid utilization.

CONCLUSIONS

Identification of risk factors for perioperative complications in ASD surgery is a priority for empowering informed choices for patients and surgeons and managing patient expectations. Risk factors with grade A and B evidence should be identified prior to elective surgery and modified to reduce the risk of perioperative complications.

Correlation between kidney function and mortality in pyogenic spondylodiscitis: the glomerular filtration rate (GFR) as new predictive parameter?

OBJECTIVE

Pyogenic spondylodiscitis is a severe medical condition, often requiring surgical intervention. Numerous risk factors are known, such as obesity, neurological impairment and old age. In-hospital mortality remains high, therefore other factors may be contributing to the increased mortality. To evaluate kidney function as a risk factor for increased morbidity of pyogenic spondylodiscitis, the glomerular filtration rate (GFR) was correlated with the patients' clinical course.

MATERIALS AND METHODS

We retrospectively reviewed the cases of 366 patients and 255 were included for analysis. Clinical, laboratory and surgical data were recorded with a minimum follow-up of three months. For clinical outcome measurement, mortality, length of stay and perioperative complications were analysed.

RESULTS

The study included 255 patients (173 men, 82 women; mean age 66.3 years). Patients with a GFR < 59 mL/min spent an average of 5 days longer in the hospital than those with a GFR ≥ 60 mL/min (p = 0.071). The mortality rate increased significantly with a decrease in GFR: A GFR of 30-59 mL/min had a mortality rate of 17.6%, whereas a GFR of < 29 mL/min had one of 30.4% (p = 0.003). Patients with impaired GFR showed an increased rate of postoperative complications (OR 4.7 p = 0.002) and higher rate of intensive care unit (ICU) stay (OR 8.7 p =  < 0.001).

DISCUSSION

Preoperative GFR values showed a significant correlation with in-hospital mortality in patients with spondylodiscitis, when graded according to the KDIGO stages. Furthermore, a GFR of < 29 ml/mL contributes to a longer ICU stay, postoperative complications and a longer total hospital stay. Therefore, the preoperative GFR could be a marker of kidney function and as a valuable predictive risk factor regarding the clinical in-hospital course of patients suffering from pyogenic spondylodiscitis.

Risk Factors for Early Mortality in Older Patients with Traumatic Cervical Spine Injuries-A Multicenter Retrospective Study of 1512 Cases

For older patients with decreased reserve function, traumatic cervical spine injuries frequently lead to early mortality. However, the prognostic factors for early mortality remain unclear. This study included patients aged ≥65 years and hospitalized for treatment of traumatic cervical spine injuries in 78 hospitals between 2010 and 2020. Early mortality was defined as death within 90 days after injury. We evaluated the relationship between early mortality and the following factors: age, sex, body mass index, history of drinking and smoking, injury mechanisms, presence of a cervical spine fracture and dislocation, cervical ossification of the posterior longitudinal ligament, diffuse idiopathic skeletal hyperostosis, American Spinal Injury Association Impairment Scale, concomitant injury, pre-existing comorbidities, steroid administration, and treatment plan. Overall, 1512 patients (mean age, 75.8 ± 6.9 years) were included in the study. The early mortality rate was 4.0%. Multivariate analysis identified older age (OR = 1.1, p < 0.001), male sex (OR = 3.7, p = 0.009), cervical spine fracture (OR = 4.2, p < 0.001), complete motor paralysis (OR = 8.4, p < 0.001), and chronic kidney disease (OR = 5.3, p < 0.001) as risk factors for early mortality. Older age, male sex, cervical spine fracture, complete motor paralysis, and chronic kidney disease are prognostic factors for early mortality in older patients with traumatic cervical spine injuries.

Risk factors for in-hospital mortality after spine surgery: a matched case-control study using a multicenter database

BACKGROUND/CONTEXT

It is yet unclear what preoperative and intraoperative factors affect mortality after spine surgery.

PURPOSE

To identify the preoperative and intraoperative risk factors for in-hospital mortality after spine surgery using a matched case-control study based on a multicenter database.

STUDY DESIGN/SETTING

A retrospective matched case-control study based on a registry of prospectively collected multicenter data.

PATIENT SAMPLE

We identified 25 patients who died in the hospital (the mortality group) from the 26,604 patients in the database who underwent spine surgery at our 27 affiliated institutions between 2012 and 2018. An age-, sex-, spinal disease-, and surgical procedure-matched control group of patients (n=100, 4:1 ratio with the mortality group) was selected from the same database.

OUTCOME MEASURES

Data relating to comorbidities, preoperative blood tests, operative factors, and perioperative complications.

METHODS

We retrospectively reviewed all the medical records of each patient in the two groups to nullify the effects of overt risk factors such as age, sex, diseases, and surgical procedures. Risk factors for in-hospital mortality were initially evaluated by univariate analysis. Then, multivariate logistic regression models were generated to analyze independent risk factors for in-hospital mortality.

RESULTS

The overall in-hospital mortality rate was 0.09% (25/26,604). Mortality was lowest in patients with degenerative cervical (0.04%, 2/5,027) or lumbar disease (0.03%, 5/15,630). In contrast, mortality was highest in patients with dialysis-related spondyloarthropathy (3.0%, 3/99), patients with infectious spondylodiscitis (1.5%, 6/401), and patients with metastatic spinal tumors (0.9%, 3/334). Multivariate logistic regression analysis revealed that massive intraoperative hemorrhage (>2 L) (odds ratio [OR], 28.2; 95% confidence interval [CI], 2.27-349), preoperative renal comorbidity (OR, 4.33; 95% CI, 1.38-13.6), and elevated preoperative aspartate aminotransferase levels (OR, 1.51 per 10 units; 95% CI, 1.04-2.20) were risk factors.

CONCLUSIONS

Spine surgery for patients with dialysis-dependency, infectious diseases or metastatic tumors had much more potential of in-hospital mortality compared with those for patients with degenerative diseases. Massive intraoperative hemorrhage and preoperative renal and liver comorbidities were identified as risk factors for in-hospital mortality in patients who underwent spine surgery.

Thoracic Kyphotic Deformity Secondary to Old Pseudomonas aeruginosa Spondylodiscitis in an Immunocompromised Patient With Persistent Infection Foci-A Case Report

Background

Kyphosis secondary to pyogenic spondylodiscitis is rare and its management can be very challenging.

Methods

In this report, we present the case of a 28-year-old woman, with past history of type 1 diabetes and kidney failure on hemodialysis. Her current complaint is chronic middle and low back pain with kyphotic attitude. She had undergone posterior fixation for T12 fracture 3 years earlier, which was complicated by surgical site infection to Pseudomonas aeruginosa, with secondary kyphosis proximally. X-ray showed a 64° kyphosis with complete fusion between T8 and T10, and MRI showed persistent infection foci.

Results

The patient underwent a pedicle subtraction osteotomy at the level of T9 with instrumentation from T5 to L1. Thoracic kyphosis was corrected to 39°. Samples taken from the remaining collections returned positive for multidrug-resistant Pseudomonas aeruginosa, and the patient was kept on intravenous antibiotic (Colistine) for 2 months. She could walk on day 1, with a satisfactory clinical and radiological result at 3 years.

Conclusions

Literature is sparse on the management of post-pyogenic infection kyphosis in immunocompromised patients. The current case shows that aggressive correction techniques such as pedicle subtraction osteotomy can be performed in such cases but within a multidisciplinary team to deal simultaneously with the different issues of the fragile patient.

Perioperative Management of Spinal Tuberculosis in Patients with End-Stage Renal Disease: A Preliminary Report on A Patient Series

OBJECTIVE

To present a preliminary experience of perioperative management for patients with spinal tuberculosis (STB) and end-stage renal disease (ESRD) and discuss strategic factors that should be considered.

METHODS

A retrospective study of 6 patients with STB and ESRD who underwent spine surgeries in our hospital from January 2010 to May 2017 was carried out. Medical records were reviewed for clinical manifestations, laboratory examinations, radiologic findings, perioperative management, clinical outcomes, and complications.

RESULTS

Except for 1 patient who died of cardiac arrest 5 days after surgery, this case series was followed with a mean follow-up period of 17.0 months (range, 9-23). There were no patients reporting major side effects related to an adjusted antituberculosis chemotherapy regimen. Postoperatively, surgical incision healed primarily, whereas delirium and pneumonia were noted in 2 patients. At final follow-ups, solid bony fusion was achieved in 4 patients, whereas fusion was indefinite in the patient who underwent surgery at L3/4 level. Visual analogue scale score improved from preoperative 5.2 ± 0.37 to 2.6 ± 0.55 at the final follow-ups.

CONCLUSIONS

Perioperative management of patients with STB and ESRD is a complicated issue, with multiple factors to be considered. Spinal surgery can achieve acceptable outcomes in these patients if meticulous management is performed.

Prevalence and risk factors for perioperative complications of CKD patients undergoing elective hip surgery

PURPOSE

Chronic kidney disease (CKD) is known to increase morbidity and mortality after orthopedic surgery. The purpose of this study is to investigate how CKD affects perioperative complications in hip surgery patients.

MATERIAL AND METHODS

From 2013 to 2016, a total of 230 patients (30 patients with CKD and 200 without CKD) undergoing hip surgery were enrolled in this study. Preoperative, intraoperative, and postoperative data was collected and analyzed between CKD and non-CKD patients. Logistic regression was used to evaluate the independent risk factor for postoperative complications.

RESULTS

There were significant differences in the number of people with hypertension (90.0% vs 27.3%, P < 0.001), diabetes (33.3% vs 8.7%, P = 0.01), coronary heart disease (20.0% vs 2.0%, P = 0.001), smoking habits (56.7% vs 22.7%, P = 0.016), anemia (90.0% vs 19.3%, P < 0.001), and low hemoglobin levels (94.1 ± 19.7 vs 121.3 ± 18.8, P < 0.001) between CKD and non-CKD patients before surgery. Receiving a blood transfusion was significantly more common in CKD patients (50% vs 28.5%, P = 0.018). Postoperatively, significant differences were detected in the average number of patients who transferred to the ICU (73.3% vs 19.3%, P < 0.001). Furthermore, differences were found in the quantity of hemoglobin (92.5 ± 16.8 vs 107.5 ± 18.3, P < 0.001) and albumin (32.4 ± 4.1 vs 34.9 ± 5.5, P = 0.02) measured between CKD and non-CKD patients. Logistic regression analysis indicated that diabetes, alcohol, and anemia were all independent risk factors for obtaining a blood transfusion, while age, CKD, and osteoporosis were all independent risk factors for ICU transfers.

CONCLUSION

Compared with non-CKD patients, CKD patients were accompanied with more cardiac diseases preoperatively. In addition, CKD patients were more likely to receive a blood transfusion and transfer to the ICU after hip surgery. Preoperative anemia should be restored sufficiently to decrease the incidence of blood transfusions.

The outcome following spinal instrumentation in haemodialyzed patients with pyogenic spondylodiscitis

Aims

The aim of this study was to evaluate the outcome of spinal instrumentation in haemodialyzed patients with native pyogenic spondylodiscitis. Spinal instrumentation in these patients can be dangerous due to rates of complications and mortality, and biofilm formation on the instrumentation.

Patients and Methods

A total of 134 haemodialyzed patients aged more than 50 years who underwent surgical treatment for pyogenic spondylodiscitis were included in the study. Their mean age was 66.4 years (50 to 83); 66 were male (49.3%) and 68 were female (50.7%). They were divided into two groups according to whether spinal instrumentation was used or not. Propensity score matching was used to attenuate the potential selection bias. The outcome of treatment was compared between these two groups.

Results

A total of 89 patients (66.4%) underwent non-instrumented surgery and 45 (33.5%) underwent instrumented surgery. There were no significant differences in the rates of postoperative complications, except for an increased rate of wound problems in the instrumented group, which was found in the unmatched cohorts (p = 0.034). There were no significant differences in the rate of recurrent infections (p = 0.328 for the unmatched cohort; p = 0.269 for the matched cohort) and mortality rate, including in-hospital (p = 0.713 for the unmatched cohort; p = 0.738 for the matched cohort) and one-year rates (p = 0.363 for the unmatched cohort; p = 0.787 for the matched cohort), between the groups. However, the interval between the initial diagnosis and the first recurrence was significantly longer in the instrumented group (p = 0.008 for the unmatched cohort; p = 0.032 for the matched cohort).

Conclusion

Instrumented surgery for haemodialyzed patients with pyogenic spondylodiscitis showed similar outcomes, including recurrence and mortality, to non-instrumented surgery, despite the instrumented group having more severe neurological deficit, a larger number of involved levels, and increased kyphotic angle.