Ninety-day readmissions after degenerative cervical spine surgery: A single-center administrative database study

Risk factors for ninety-day readmission following cervical surgery: a meta-analysis

Background

As an important evaluation index after cervical surgery, ninety-day readmission is gradually being valued. Our study collected the latest published relevant studies, analyzed the risk factors of ninety-day readmission after cervical surgery, and continuously improved the postoperative rehabilitation plan. This study focuses on two research hotspots: (1) What is the rate of ninety-day readmission after cervical surgery? (2) What are the risk factors affecting the ninety-day readmission?

Methods

Based on the Cochrane Library, PubMed, Web of Science, and Embase databases, this study searched for studies about ninety-day readmission after cervical surgery, from the establishment of the database to August 1, 2022. The evaluation indicators are as follows: age, American Society of Anesthesiology physical status (ASA) class, diabetes, hypertension, chronic heart diseases, chronic lung diseases, income, and payments for hospitalization. The meta-analysis was performed using Review Manager 5.4.

Results

Seven studies with 222,490 participants were eligible for our meta-analysis. The analysis displayed that there were statistically significant differences in the age (MD = − 4.60, 95%CI − 4.89–4.31, p < 0.001), diabetes (OR = 0.60, 95%CI 0.56–0.64, p < 0.00001), hypertension (OR = 0.40, 95%CI 0.30–0.54, p < 0.00001), chronic heart diseases (OR = 0.05, 95%CI 0.01–0.19, p < 0.00001), chronic lung diseases (OR = 0.46, 95%CI 0.43–0.49, p < 0.00001), income (OR = 2.85, 95%CI 1.82–4.46, p < 0.00001), and payments for hospitalization (OR = 2.29, 95%CI 1.14–4.59, p = 0.02) between readmission and no readmission groups. In terms of the ASA, there was no difference on the ninety-day readmission (p = 0.78).

Conclusion

Age, diabetes, hypertension, chronic heart diseases, chronic lung diseases, income, and payments for hospitalization are the risk factors of ninety‐day readmission following cervical surgery.

Increased Surgical Site Subcutaneous Fat Thickness Is Associated with Infection after Posterior Cervical Fusion

Background: Previous literature has associated increased body mass index (BMI) with risk of surgical site infection (SSI) after posterior cervical fusion (PCF) surgery. However, few studies have examined the association between local adiposity and risk of SSI, re-admission, and re-operation after PCF. Local adiposity is easily measured on pre-operative magnetic resonance imaging (MRI) and may act as a more accurate predictor compared with BMI. Patients and Methods: Subjects undergoing PCF from 2013-2018 at a single institution were identified retrospectively. Posterior cervical subcutaneous fat thickness, paraspinal muscle thickness, and lamina-to-skin distance measurements were obtained from computed tomography (CT) or MRI scans. Subjects with active infection, malignancy, or revision procedures were excluded. Results: Two hundred five patients were included with 20 developing SSIs. Subjects with SSIs had a longer fusion construct (4.90 vs. 3.71 levels; p = 0.001), higher Elixhauser comorbidity index (ECI; 2.05 vs. 1.34; p = 0.045), had a history of diabetes mellitus (30% vs. 10.8%; p = 0.026), higher subcutaneous fat thickness (30.5 vs. 23.6 mm; p = 0.013), and higher lamina-to-skin distance (66.4 vs. 57.9 mm; p = 0.027). Subcutaneous fat thickness (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01-1.10]; p = 0.026) and lamina-to-skin distance (OR, 1.05; 95% CI, 1.01-1.09]; p = 0.014) were associated with SSI in multivariable analysis. A subcutaneous fat thickness cutoff value of 23.2 mm had 90% sensitivity and 54.1% specificity for prediction of SSI. There was no association need for re-admission or re-operation. Conclusions: Increased posterior cervical fat may increase the risk of SSI after PCF. Pre-operative advanced imaging may be a valuable tool for assisting with patient counseling, optimization, and risk stratification.

IDENTIFICATION OF RISK FACTORS ASSOCIATED WITH 30-DAY READMISSION OF PATIENTS SUBMITTED TO ANTERIOR OR POSTERIOR ACCESS CERVICAL SPINE SURGERY

ABSTRACT Aim: To conduct a systematic review of the literature to identify risk factors associated with 30-day readmission of patients submitted to anterior or posterior access cervical spine surgery. Methods: The databases used to select the papers were PubMed, Web of Science, and Cochrane, using the following search strategy: patient AND readmission AND (30 day OR “thirty day” OR 30-day OR thirty-day) AND (spine AND cervical). Results: Initially, 179 papers that satisfied the established search stringwere selected. After reading the titles and abstracts, 46 were excluded from the sample for not effectively discussing the theme proposed for this review. Of the 133 remaining papers, 109 were also excluded after a detailed reading of their content, leaving 24 that were included in the sample for the meta-analysis. Conclusions: The average readmission rate in the studies evaluated was 4.85%. Only the occurrence of infections, as well as the presence of patients classified by the American Society of Anesthesiology (ASA) assessment system with scores greater than III, were causal factors that influenced the readmission of patients. No significant differences were noted when comparing the anterior and posterior surgical access routes. Level of evidence II; Systematic Review of Level II or Level I Studies with discrepant results.

National Rates, Reasons, and Risk Factors for 30- and 90-Day Readmission and Reoperation Among Patients Undergoing Anterior Cervical Discectomy and Fusion: An Analysis Using the Nationwide Readmissions Database

STUDY DESIGN

Retrospective cohort study of the Nationwide Readmissions Database (NRD).

OBJECTIVE

To determine causes of and independent risk factors for 30- and 90-day readmission in a cohort of anterior cervical discectomy and fusion (ACDF) patients.

SUMMARY OF BACKGROUND DATA

Identifying populations at high-risk of 30-day readmission is a priority in healthcare reform so as to reduce cost and patient morbidity. However, among patients undergoing ACDF, nationally-representative data have been limited, and have seldom described 90-day readmissions, early reoperation, or socioeconomic influences.

METHODS

We queried the NRD, which longitudinally tracks 49.3% of hospitalizations, for all adult patients undergoing ACDF. We calculated the rates of, and determined reasons for, readmission and reoperation at 30 and 90 days, and determined risk factors for readmission at each timepoint.

RESULTS

We identified 50,126 patients between January and September 2014. Of these, 2294 (4.6%) and 4152 (8.3%) were readmitted within 30 and 90 days of discharge, respectively, and were most commonly readmitted for infections, medical complications, and dysphagia. The characteristics most strongly associated with readmission were Medicare or Medicaid insurance, length of stay greater than or equal to 4 days, three or more comorbidities, and non-routine discharge, whereas surgical factors (e.g., greater number of vertebrae fused) were more modest. By 30 and 90 days, 8.2% and 11.7% of readmitted patients underwent an additional spinal procedure, respectively.

CONCLUSION

Our analysis uses the NRD to thoroughly characterize readmission in the general ACDF population. Readmissions are often delayed (after 30 days), strongly associated with insurance status, and many result in reoperation. Our results are crucial for risk-stratifying future ACDF patients and developing interventions to reduce readmission.Level of Evidence: 3.

Smoking Is an Independent Risk Factor for 90-Day Readmission and Reoperation Following Posterior Cervical Decompression and Fusion

BACKGROUND

Posterior cervical decompression and fusion (PCF) is a common procedure used to treat various cervical spine pathologies, but the 90-d outcomes following PCF surgery continue to be incompletely defined.

OBJECTIVE

To identify risk factors associated with 90-d readmission and reoperation following PCF surgery.

METHODS

Adults undergoing PCF from 2012 to 2020 were identified. Demographic and radiographic data, surgical characteristics, and 90-d outcomes were collected. Univariate analysis was performed using Student's t-test, chi square, and Fisher exact tests as appropriate. Multivariable logistic regression models with lasso penalty were used to analyze various risk factors.

RESULTS

A total of 259 patients were included. The 90-d readmission and reoperation rates were 9.3% and 4.6%, respectively. The most common reason for readmission was surgical site infection (SSI) (33.3%) followed by new neurological deficits (16.7%). Patients who smoked tobacco had 3-fold greater odds of readmission compared to nonsmokers (odds ratio [OR]: 3.48; 95% CI 1.87-6.67; P = .0001). Likewise, the most common reason for reoperation was SSI (33.3%) followed by seroma and implant failure (25.0% each). Smoking was also an independent risk factor for reoperation, associated with nearly 4-fold greater odds of return to the operating room (OR: 3.53; 95% CI 1.53-8.57; P = .003).

CONCLUSION

Smoking is a significant predictor of 90-d readmission and reoperation in patients undergoing PCF surgery. Smoking cessation should be strongly considered preoperatively in elective PCF cases to minimize the risk of 90-d readmission and reoperation.

Unplanned hospital readmission after surgical treatment for thoracic spinal stenosis: incidence and causative factors

BACKGROUND

To assess the incidence and causative factors of unplanned hospital readmission within 90 days after surgical treatment of thoracic spinal stenosis (TSS).

METHODS

Hospital administrative database was queried to identify patients who underwent surgical treatment of TSS from July 2010 through December 2017. All unplanned readmissions within 90 days of discharge were reviewed for causes and the rate of unplanned readmissions was calculated. Patients of unplanned readmission were matched 1:3 to a control cohort without readmission.

RESULTS

Twenty-one patients (incidence of 1.7 % in 1239 patients) presented unplanned hospital readmission within a 90-day period and enrolled as the study group, 63 non-readmission patients (a proportion of 1: 3) were randomly selected as the control group. Causes of readmission include pseudomeningocele (8 patients; 38 %), CSF leakage combined with poor incision healing (6 patients; 29 %), wound dehiscence (2 patient; 9 %), surgical site infection (2 patients; 9 %), spinal epidural hematoma (1 patient; 5 %), inadequate original surgical decompression (2 patients; 9 %). Mean duration from re-admission to the first surgery was 39.6 ± 28.2 days, most of the patients readmitted at the first 40 days (66.7 %, 14/21 patients). When compared to the non-readmitted patients, diagnosis of OPLL + OFL, circumferential decompression, dural injury, long hospital stay were more to be seen in readmitted patients.

CONCLUSIONS

The incidence of 90-day unplanned readmission after surgical treatment for TSS is 1.7 %, CSF leakage and pseudomeningocele were the most common causes of readmission, the peak period of readmission occurred from 10 to 40 days after surgery, patients should be closely followed up within this period.

Analysis of unplanned hospital readmissions up to 2-years after metastatic spine tumour surgery

PURPOSE

The aim of this study was to investigate rates, causes, and risk factors of unplanned hospital readmissions (UHR) within 30 days, 90 days, 1 year and 2 years after metastatic spine tumour surgery (MSTS) to augment multi-disciplinary treatment planning and improve patient education.

METHODS

We retrospectively reviewed 272-patients who underwent MSTS between 2005 and 2016. Hospital records were utilised to obtain demographics, oncological, procedural details, and postoperative outcomes. All UHR within 2 years were reviewed. Primary outcomes were rates, causes, and risk factors of UHR. Risk factors for UHR were evaluated utilising multivariate logistic regression analysis.

RESULTS

Thirty-day, 90 day, 1 year, and 2 year UHR-rates after MSTS were 17.2%, 31.1%, 46.2%, and 52.7%, respectively. Lung cancer primaries had the highest UHR-events (24.7%) whilst renal/thyroid displayed the least (6.6%). Disease-related causes (16.2%) were the most common reason for readmissions across all timeframes, followed by respiratory (13.7%) and progression of metastatic spine disease (12.7%). Urological conditions accounted for majority of readmissions within 30-days; disease-related causes, symptomatic spinal metastases, and respiratory conditions represented the most common causes at 30-90 days, 90 days-1 year, and 1-2 years, respectively. An ECOG >1 (p = 0.057), CCI >7 (p = 0.01), and primary lung tumour (p = 0.02) significantly increased UHR-risk on multivariate analysis.

CONCLUSION

Seventy-four percent of patients had at least one UHR within 2 years of MSTS and majority were secondary to disease-related causes. Majority of first UHR occurred between 30 and 90 days post-surgery. Local disease progression and overall disease progression account for the highest UHR-events at 90 days-1 year and 1-2 year timeframes, respectively. We define UHR in specific timeframes, thus enabling better surveillance and reducing unnecessary morbidity.

Cervical Spinal Fusion in Adult Patients With Rheumatoid Arthritis: A National Analysis of Complications and 90-day Readmissions

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to utilize the National Readmission Database to determine the national estimates of complication and 90-day readmission rates associated with cervical spinal fusion in adult patients with rheumatoid arthritis (RA).

SUMMARY OF BACKGROUND

RA patients who undergo cervical spine surgery are known to be at high risk for readmissions, which are costly and may not be reimbursed by Medicare.

METHODS

The National Readmission Database was queried for adults (>18 years) diagnosed with RA undergoing cervical spine fusion. Patient, operative, and hospital factors were assessed in bivariate analyses. Independent risk factors for readmissions were identified using stepwise multivariate logistic regression.

RESULTS

From 2013 to 2014, a total of 5597 RA patients (average age: 61.5 ± 11.2 years, 70.9% female) underwent cervical spine fusion. A total of 691 (12.3%) patients were readmitted within 90 days (). Index inpatient complications included dysphagia (readmitted: 7.9% vs. non-readmitted: 5.1%; P = 0.003), urinary tract infection (UTI) (8.8% vs. 3.7%; P < 0.001), respiratory-related complications (7.6% vs. 3.4%; P < 0.001), and implant-related complications (5.4% vs. 2.7%; P < 0.001). Multivariate logistic regression demonstrated the following as the strongest independent predictors for 90-day readmission: intraoperative bleeding (odds ratio [OR]: 3.6, P = 0.001), inpatient Deep Vein Thrombosis (DVT) (OR 4.1, P = 0.004), and patient discharge against medical advice (OR 33.5, P = 0.001).

CONCLUSION

Readmission rates for RA patients undergoing cervical spine surgery are high and most often due to postoperative infection (septicemia, UTI, pneumonia, wound). Potential modifiable factors which may improve outcomes include minimizing intraoperative blood loses, postoperative DVT prophylaxis, and discharge disposition.

LEVEL OF EVIDENCE

3.

Risk Factors Associated with 90-Day Readmissions Following Occipitocervical Fusion-A Nationwide Readmissions Database Study

BACKGROUND

Occipitocervical fusion (OCF) procedures are increasing due to an aging population and the prevalence of trauma, rheumatoid arthritis, and tumors. Reoperation rates and readmission risk factors for cervical fusions have been established, but in relation to OCF they have not been explored. This study investigates the patterns of readmissions and complications following OCF using a national database.

METHODS

The 2016 U.S. Nationwide Readmissions Database was used for sample collection. Adults (>18 years) who underwent OCF were identified using the 2016 ICD-10 coding system, and we examined the readmission rates (30-day and 90-day) and reoperation rates.

RESULTS

Between January and September 2016, a total of 477 patients underwent OCF; the 30-day and 90-day readmission rates were 10.4% and 22.4%, respectively. The 90-day reoperation rate related to the index surgery was 5.7%. Mean age (68.58 years) was significantly greater in the readmitted group versus nonreadmitted group (61.76 years) (P < 0.001). The readmitted group had a significantly higher Charlson Comorbidity Index and Elixhauser Comorbidity Index (5.00 and 2.41, respectively) than the nonreadmitted group (3.25 and 1.15, respectively; P < 0.001). Nonelective OCF showed a higher readmission rate (29.18%) versus elective OCF (12.23%) (P < 0.001). Medicare and Medicaid patients showed the highest rates of readmission (27.27% and 20.41%, respectively). Readmitted patients had higher total health care costs.

CONCLUSIONS

Nonelective OCF was found to have a readmission rate of almost 2½× that of elective OCF. Understanding risk factors associated with OCF will help with operative planning and patient optimization.

Early and late hospital readmissions after spine deformity surgery in children with cerebral palsy

STUDY DESIGN

Retrospective review of a prospectively collected multicenter registry of pediatric patients with cerebral palsy (CP) and neuromuscular scoliosis (NMS) undergoing spinal fusion.

OBJECTIVE

To define risk factors for unplanned readmission after elective spinal deformity surgery. Patients with CP and NMS have high rates of hospital readmission; however, risk factors for readmission are not well established.

METHODS

Univariate and multivariate analyses were used to compare the demographics, operative and postoperative course, radiographic characteristics, and preoperative Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) questionnaires of patients who did not require readmission to those who required either early readmission (within 90 days of the index surgery) or late readmission (readmission after 90 days).

RESULTS

Of the 218 patients identified, 19 (8.7%) required early readmission, while 16 (7.3%) required late readmission. Baseline characteristics were similar between the three cohorts. On univariate analysis, early readmission was associated with longer duration of surgery (p < 0.001) and larger magnitude of residual deformity (p = 0.003 and p = 0.029 for postoperative major and minor angles, respectively). The health score of the CPCHILD Questionnaire was lower in patients who required early readmission than in those who did not require readmission (p = 0.032). On multivariate analysis, oral feeding status was inversely related to early readmission (less likely to require readmission), while decreasing lumbar lordosis and increasing length of surgery were related to an increased likelihood of early readmission.

CONCLUSIONS

In patients with CP and NMS, longer surgical time, larger residual major and minor Cobb angles, lumbar lordosis, feeding status, and overall health may be related to a greater likelihood for early hospital readmission after elective spinal fusion. No factors were identified that correlated with an increased need for late hospital readmission after elective spinal fusion in patients with CP.

LEVEL OF EVIDENCE

IV.

Rates and risk factors associated with 90-day readmission following cervical spine fusion surgery: analysis of the Michigan Spine Surgery Improvement Collaborative (MSSIC) registry

BACKGROUND CONTEXT

Hospital readmission rates are an increasingly important focus. Identifying patients at risk for readmission can help decrease those rates and thus decrease the overall cost of care.

PURPOSE

We sought to report the rates and the risk factors associated with 90-day hospital readmission after degenerative cervical spine surgery via either an anterior or posterior approach.

STUDY DESIGN

Retrospective review of prospectively collected database PATIENT SAMPLE: Michigan Spine Surgery Improvement Collaborative (MSSIC) registry OUTCOME MEASURES: Hospital readmission at 90 days METHODS: The MSSIC registry prospectively enrolls patients undergoing surgery for degenerative cervical spine disease. The registry was queried over a 4-year period to determine patient characteristics and risk factors associated with unplanned readmission at 90 days following degenerative cervical spine fusion surgery through either an anterior or posterior approach. Univariate and multivariate regression modeling was used to compare patient characteristics and odds of readmission.

RESULTS

Of 3,762 patients who underwent an anterior approach, 202 (5.4%) were readmitted within 90 days. Of 693 patients who underwent a posterior approach, 85 (12.3%) were readmitted within 90 days. Risk factors associated with increased likelihood of readmission after the anterior approach were male sex (odds ratio [OR] 1.56, confidence interval [CI] 1.10-2.20), American Society of Anesthesiologists class >2 (OR 1.70, CI 1.26-2.30), and increased length of stay (OR 1.10, CI 1.03-1.19). Factors associated with decreased likelihood of readmission after the anterior approach were being independently ambulatory preoperatively (OR 0.59, CI 0.46-0.76) and holding private insurance (OR 0.67, CI 0.50-0.90). A history of previous spine surgery was associated with increased risk of readmission after the posterior approach (OR 1.76, CI 1.37-2.25). Pain was the most common single reason cited for readmission after either approach (9% anterior, 13% posterior). After an anterior approach, common surgical reasons for readmission include new radicular findings (8%), dysphagia (6%), and surgical site hematoma (5%), whereas common medical reasons include pneumonia (7%), infection outside the surgical site (6%), and an electrolyte issue. After a posterior approach, common surgical reasons for readmission after 90 days include surgical site infection (8%) and new radicular findings (6%), whereas common medical reasons include infection outside the surgical site (9%), urinary tract infection (8%), and an abdominal issue (8%).

CONCLUSIONS

Analysis of a large multicentered, spine-specific database for elective cervical spine fusion surgery demonstrated an unplanned 90-day readmission rate of 5.4% for the anterior approach and 12.3% for the posterior approach. Factors associated with readmission for the anterior approach include male sex, American Society of Anesthesiologists class >2, increased length of stay, holding private insurance, and being ambulatory preoperatively. A history of previous spine surgery was associated with increased odds of readmission after the posterior approach.

Risk factors for 90-day reoperation and readmission after lumbar surgery for lumbar spinal stenosis

OBJECTIVES

The objective of this study was to evaluate the incidence and risk factors for 90-day readmission and reoperation after elective surgery for lumbar spinal stenosis (LSS).

METHODS

The authors performed a retrospective consecutive cohort analysis of patients undergoing posterior lumbar decompression with or without fusion for LSS with claudication from January 2014 through December 2015.

RESULTS

Data were collected on 1592 consecutive patients. The mean age at surgery was 67.4 ± 10.1 years and 45% of patients were female. The 90-day reoperation rate was 4.7%, and 69.3% of the reoperations occurred within the first 30 days. The 90-day readmission rate was 7.2%. Multivariable analysis showed that postoperative development of a surgical site infection (SSI; odds ratio [OR] 14.09, 95% confidence interval [CI] 7.86–25.18), acute kidney injury (AKI; OR 6.76, 95% CI 2.39–19.57), and urinary tract infection (UTI; OR 3.96, 95% CI 2.43–6.37), as well as a history of congestive heart failure (CHF; OR 3.03, 95% CI 1.69–5.28), were significant risk factors for readmission within 90 days. Male sex (OR 0.60, 95% CI 0.38–0.92) was associated with decreased odds for readmission. With regards to reoperation, development of SSI (OR 25.06, 95% CI 13.54–46.51), sepsis (OR 7.63, 95% CI 1.52–40.59), UTI (OR 2.54, 95% CI 1.31–4.76), and increased length of stay (LOS; OR 1.25, 95% CI 1.17–1.33) were found to be significant risk factors. A subsequent analysis found that morbid obesity (OR 6.99), history of coronary artery disease (OR 2.263), increased duration of surgery (OR 1.004), and LOS (OR 1.07) were significant risk factors for developing an SSI.

CONCLUSIONS

Overall, this study found rates of 4.7% and 7.2% for reoperation and readmission, respectively, within 90 days: 30.7% of the reoperations and 44.7% of the readmissions occurred beyond the first 30 days. A diagnosis of SSI, AKI, UTI, and history of CHF were significant factors for readmission, while male sex was associated with decreased odds for readmission. A diagnosis of SSI, sepsis, UTI, and increased LOS were found to be significant predictors for reoperation. Understanding 90-day complication rates is imperative because there has been increased discussion and healthcare policy extending the global postoperative window to 90 days. Current literature supports a readmission rate of 3%–9% after spine surgery. However, this literature either is limited to a 30-day window or does not stratify between different types of spine surgeries.

ABBREVIATIONS

AKI = acute kidney injury; BPH = benign prostate hyperplasia; CAD = coronary artery disease; CHF = congestive heart failure; CI = confidence interval; CMS = Centers for Medicare and Medicaid Services; COPD = chronic obstructive pulmonary disease; DM = diabetes mellitus; EBL = estimated blood loss; LOS = length of stay; LSS = lumbar spinal stenosis; OR = odds ratio; POUR = postoperative urinary retention; SSI = surgical site infection; UTI = urinary tract infection.

30- and 90-Day Unplanned Readmission Rates, Causes, and Risk Factors After Cervical Fusion: A Single-Institution Analysis

STUDY DESIGN

Retrospective cohort study OBJECTIVE.: To study 30- and 90-day readmission rates, causes, and risk factors after anterior cervical discectomy and fusion (ACDF) and posterior cervical fusion (PCF).

SUMMARY OF BACKGROUND DATA

Existing data on readmission after cervical fusion is majorly derived from national databases. Given their inherent limitations in accuracy, follow-up available, and missing data, we intend to add to literature from our institutional analysis.

METHODS

Patients who underwent ACDF and PCF for degenerative cervical pathology in 2013 and 2014 were identified for the study. Comprehensive chart review was performed to record demographics and clinical patient profile. Hospital readmission within 30 and 90 days was identified, and the causes and management were recorded. Binary logistic regression analysis was done to study risk factors for readmission. ACDF and PCF were studied separately.

RESULTS

Our analysis included a total of 549 patients, stratified as 389 ACDFs and 160 PCFs. The 30- and 90-day unplanned readmission rate was 5.1% and 7.7% after ACDF. These rates were 11.2% and 16.9% after PCF. The most common cause of readmission was systemic infection and sepsis after ACDF and PCF (31.4% and 25.8% of readmitted, respectively), followed by pulmonary complications after ACDF (14.3% of readmitted) and wound complications after PCF (19.4% of readmitted). Predictors of readmission after ACDF included heart failure, history of malignancy, history of deep vein thrombosis/pulmonary embolism, and any intraoperative complication. In the PCF cohort, history of ischemic heart disease, increasing number of fusion levels and longer length of stay were independently predictive.

CONCLUSION

The rates, causes, and risk factors of readmission after ACDF and PCF have been identified. There is variation in published data regarding the incidence and risk factors for readmission after cervical fusion; however, majority of readmissions occur due to medical complications and systemic infection.

LEVEL OF EVIDENCE

3.

Predictive Model for Medical and Surgical Readmissions Following Elective Lumbar Spine Surgery: A National Study of 33,674 Patients

STUDY DESIGN

This study retrospectively analyzes prospectively collected data.

OBJECTIVE

Here we aim to develop predictive models for 3-month medical and surgical readmission after elective lumbar surgery, based on a multi-institutional, national spine registry.

SUMMARY OF BACKGROUND DATA

Unplanned readmissions place considerable stress on payers, hospitals, and patients. Medicare data reveals a 30-day readmission rate of 7.8% for lumbar-decompressions and 13.0% for lumbar-fusions, and hospitals are now being penalized for excessive 30-day readmission rates by virtue of the Hospital Readmissions Reduction Program.

METHODS

The Quality and Outcomes Database (QOD) was queried for patients undergoing elective lumbar surgery for degenerative diseases. The QOD prospectively captures 3-month readmissions through electronic medical record (EMR) review and self-reported outcome questionnaires. Distinct multivariable logistic regression models were fitted for surgery-related and medical readmissions adjusting for patient and surgery-specific variables.

RESULTS

Of the total 33,674 patients included in this study 2079 (6.15%) reported at least one readmission during the 90-day postoperative period. The odds of medical readmission were significantly higher for older patients, males versus females, African Americans versus Caucasion, those with higher American Society of Anesthesiologists (ASA) grade, diabetes, coronary artery disease, higher numbers of involved levels, anterior only or anterior-posterior versus posterior approach; also, for patients who were unemployed compared with employed patients and those with high baseline Oswestry Disability Index (ODI). The odds of surgery-related readmission were significantly greater for patients with a higher body mass index (BMI), a higher ASA grade, female versus male, and African Americans versus Caucasians; also, for patients with severe depression, more involved spinal levels, anterior-only surgical approaches and higher baseline ODI scores.

CONCLUSION

In this study we present internally validated predictive models for medical and surgical readmission after elective lumbar spine surgery. These findings set the stage for targeted interventions with a potential to reduce unnecessary readmissions, and also suggest that medical and surgical readmissions be treated as distinct clinical events.

LEVEL OF EVIDENCE

3.

30-Day unplanned surgery in cervical spondylotic myelopathy surgically treated: a single-center experience

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Analyze the rate and risk factors associated with Unplanned Surgeries (US) during the first 30 days in patients treated for cervical spondylotic myelopathy.

BACKGROUND

US are often regarded as a potentially useful quality of care indicator.

METHODS

We defined US as any, non-planned, surgical procedure as a complication after "index" surgery. Demographic data, comorbidities, ASA, smoking status, surgical details and postoperative complications were collected. We conducted a subjective outcome test using the Global Outcome Score (GOS). To assess risk factors, a bivariate analysis was performed using T Student or Chi-square. Risk is shown as odds ratio (OR) with 95% confidence interval (CI). Multivariable logistic regression models with bootstrap resampling procedure were performed.
 RESULTS: The study included 303 patients (200 men) with mean age of 57.7 years (27-86) and mean follow-up of 75.35 months (16-126 m). 63.3% patients were ASA 1 or 2 and 41.9% were smokers. 77.9% of patients had some comorbidity. Anterior approach surgeries were 65.7%. Perioperative complications: 29% medical, 8.9% intraoperative and 3% implant related. US rate was 2.6%. Causes for revision were postoperative infection or deep hematomas. After bivariate analysis, the risk factors associated were diabetes mellitus (OR 2.6; 95% CI 1-5.5) and intraoperative complications (OR 6.5, 95% CI 1-40). The presence of US does not have influence in satisfaction using GOS score.

CONCLUSIONS

Our US rate was 2.6%, similar to the literature. Diabetics and patients suffering an intraoperative complication are more likely to need an early reinterventions (OR 2.2 and 6.5, respectively). US did not alter the patient's outcomes. These slides can be retrieved under Electronic Supplementary Material.

Predictors of 30-Day Hospital Readmission After Posterior Cervical Fusion in 3401 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of the study was to determine readmission rates and predictors of readmission after posterior cervical fusion (PCF).

SUMMARY OF BACKGROUND DATA

PCFs are common spinal operations for a variety of spinal disorders including cervical myelopathy, unstable fractures, cervical deformity, and tumors. Data elaborating on risk factors for 30-day readmission are limited.

METHODS

Data were collected from the 2006 to 2013 American College of Surgeons National Surgical Quality Improvement Program database. Predictors of 30-day readmission comprising patient demographics, comorbidities, operative features, and postoperative complications were identified through logistic multivariable regression.

RESULTS

A total of 3401 patients met study criteria. Rate of 30-day readmission was 6.20%. Multilevel fusion was performed in 69.16% of patients. Postoperative infection was the most reason, accounting for 17.06% of all readmissions. Age older than 70 years (odds ratio [OR] = 1.61, P = 0.012), renal failure requiring dialysis (OR = 3.69, P = 0.011), anemia (OR = 1.57, P = 0.006), multilevel fusion (OR = 1.61, P = 0.012), surgical site infections (OR = 20.4, P < 0.001), wound dehiscence (OR = 19.08, P < 0.001), postoperative pneumonia (OR = 2.75, P = 0.01), pulmonary embolism (OR = 15.39, P < 0.001), and progressing renal insufficiency (OR = 10.13, P = 0.061) were significant predictors of hospital readmission.

CONCLUSION

The identified predictors of readmission after PCF can improve patient counseling, identification of high-risk patients, and guide changes in healthcare delivery pathways. Patients with modifiable risk factors such as anemia and kidney failure may benefit from preoperative optimization. In addition, postoperative complications represent a key target for intervention.

LEVEL OF EVIDENCE

3.

Cervical Total Disc Replacement and Anterior Cervical Discectomy and Fusion: Reoperation Rates, Complications, and Hospital Resource Utilization in 72 688 Patients in the United States

BACKGROUND

Healthcare readmissions are important causes of increased cost and have profound clinical impact. Thirty-day readmissions in spine surgery have been well documented. However, rates, causes, and outcomes are not well understood outside 30 d.

OBJECTIVE

To analyze 30- and 90-d readmissions for a retrospective cohort of anterior cervical discectomy and fusions (ACDF) and total disc replacement (TDR) for degenerative cervical conditions.

METHODS

The Nationwide Readmissions Database approximates 50% of all US hospitalizations with patient identifiers to track patients longitudinally. Patients greater than 18 yr old were identified. Rates of readmission for 30 and 90 d were calculated. Predictor variables, complications, outcomes, and costs were analyzed via univariate and multivariable analyses.

RESULTS

Between January and September 2013, 72 688 patients were identified. The 30- and 90-d readmission rates were 2.67% and 5.97%, respectively. The most prevalent reason for 30-d readmission was complication of medical/surgical care (20.3%), whereas for 90-d readmission it was degenerative spine etiology (19.2%). Common risk factors for 30- and 90-d readmission included older age, male gender, Medicare/Medicaid, prolonged initial length of stay, and various comorbidities. Unique risk factors for 30- and 90-d readmissions included adverse discharge disposition and mechanical implant-related complications, respectively. When comparing ACDF and TDR, ACDFs were associated with increased 90-d readmissions (6.0% vs 4.3%). The TDR cohort had a shorter length of stay, lower complication rate, and fewer adverse discharge dispositions.

CONCLUSION

Identification of readmission causes and predictors is important to potentially allow for changes in periperative management. Decreasing readmissions would improve patient outcomes and reduce healthcare costs.

Preoperative Nomograms Predict Patient-Specific Cervical Spine Surgery Clinical and Quality of Life Outcomes

BACKGROUND

Clinical and quality of life (QOL) outcomes vary depending on the patient's demographics, comorbidities, presenting symptoms, pathology, and surgical treatment used. While there have been individual predictors identified, no comprehensive method incorporates a patient's complex clinical presentation to predict a specific individual postoperative outcome.

OBJECTIVE

To create tool that predicts patient-specific outcomes among those undergoing cervical spine surgery.

METHODS

A total of 952 patients at a single tertiary care institution who underwent anterior or posterior cervical decompression/fusion between 2007 and 2013 were retrospectively reviewed. Outcomes included postoperative emergency department visit or readmission within 30 d, reoperation within 90 d for infection, and changes in QOL outcomes. Nomograms were modeled based on patient demographics and surgical variables. Bootstrap was used for internal validation.

RESULTS

Bias-corrected c-index for emergency department visits, readmission, and reoperation were 0.63, 0.78, and 0.91, respectively. For the QOL metrics, the bias-corrected adjusted R-squared was EQ-5D (EuroQOL): 0.43, for PHQ-9 (Patient Health Questionnaire-9): 0.35, and for PDQ (Pain/Disability Questionnaire): 0.47. Variables predicting the clinical outcomes varied, but included race and median income, body mass index, comorbidities, presenting symptoms, indication for surgery, surgery type, and levels. For the QOL nomograms, the predictors included similar variables, but were significantly more affected by the preoperative QOL of the patient.

CONCLUSION

These prediction models enable referring physicians and spine surgeons to provide patients with personalized expectations regarding postoperative clinical and QOL outcomes following a cervical spine surgery. After appropriate validation, use of patient-specific prediction tools, such as nomograms, has the potential to lead to superior spine surgery outcomes and more cost effective care.

National Rates, Causes, Risk Factors, and Outcomes Associated With 30-Day and 90-Day Readmissions Following Degenerative Posterior Cervical Spine Surgery Utilizing the Nationwide Readmissions Database

BACKGROUND

Hospital readmissions have profound financial and clinical impacts. Analyses of 30-day readmissions following spine surgery have been previously reported utilizing administrative databases. However, time periods outside the initial 30 days have not been well studied. Furthermore, these databases have limitations regarding coding and institutional crossover.

OBJECTIVE

The authors sought to analyze 30-day and 90-day readmission rates and risk factors using the Nationwide Readmissions Database (NRD) in a retrospective cohort receiving elective, posterior cervical spine surgery for degenerative conditions.

METHODS

NRD is a new source containing approximately 50% of US hospitalizations, with patient-linkage numbers to longitudinally track patients. Patients 18 years of age or older were identified. Preoperative characteristics, demographics, and surgical characteristics were chosen for predictor variables. Thirty-day and 90-day readmission rates were calculated. Statistical analysis was completed using SPSS v.23 software via univariate and multivariate analyses.

RESULTS

Between January and September 2013, a total of 29 990 patients were identified. Readmission rates for 30- and 90-days were 5.4% and 10.0%, respectively. The most common reason for readmission during 30-day and 90-day periods was complications of surgical and/or medical care (31.0% vs 21.9%, respectively). The strongest risk factors for 30-day readmission included wound dehiscence, weekend admission at index hospitalization, coagulopathy, and incidental durotomy. The strongest risk factors for 90-day readmission included thromboembolic complications, postoperative hemorrhage, and comorbidities.

CONCLUSION

Identification of predictors of readmission is important to allow for changes in perioperative management to potentially reduce readmissions and improve outcomes. Additionally, knowledge about readmission risk factors allows for preoperative counseling.

Readmission Rates, Reasons, and Risk Factors Following Anterior Cervical Fusion for Cervical Spondylosis in Patients Above 65 Years of Age

STUDY DESIGN

A retrospective database review.

OBJECTIVE

The aim of this study was to determine readmission reasons and rates following primary, elective anterior cervical spinal fusion surgery for cervical spondylosis and determine risk factors predicting increased risk of 30-day readmission in an exclusively elderly population.

SUMMARY OF BACKGROUND DATA

In the United States, there were almost 190,000 cervical spine procedures in 2009. Many cervical spine surgery patients are elderly, a demographic increasingly requiring surgery for degenerative cervical spine pathology. Unfortunately, this patient population is poorly studied, particularly concerning readmission rates.

METHODS

Medicare data from 2005 to 2012 were queried for elderly patients (65-84 years) who underwent primary one to two and ≥three-level anterior cervical spine fusion surgeries for cervical spondylosis. Forty-five thousand two hundred eighty-four patients treated with one to two-level and 12,103 patients with ≥three-level anterior cervical fusion (ACF) were identified and included in two study cohorts. Reasons for and rates of readmission were determined within 30 days, 90 days, and one-year postoperatively. Risk factors for medical, surgical, and all 30-day readmissions were also determined, selecting from various comorbidities, demographics, and surgical variables.

RESULTS

Readmission rates of 1.0% to 1.4%, 2.7% to 3.6%, and 13.2% to 14.1% were observed within 30 days, 90 days, and one year. Within 30 days, over 30% of patients from both study cohorts were readmitted for surgical reasons. Of surgical reasons for 30-day readmission, hematoma/seroma diagnoses were the most frequent (11.4%-15.4% of all readmissions). Male gender, diabetes mellitus, chronic pulmonary disease, obesity, and smoking history were all found to be predictive of all-cause readmissions.

CONCLUSION

Unplanned 30-day readmission rates following primary, elective ACF in elderly patients is low and often due to medical reasons. Frequent surgical reasons for 30-day readmission include hematoma/seroma formation. Male gender and various comorbid diagnoses are significant predictors of all-cause readmissions within 30 days.

LEVEL OF EVIDENCE

3.

Costs and readmission rates for the resection of primary and metastatic spinal tumors: a comparative analysis of 181 patients

OBJECTIVE

Because the surgical strategies for primary and metastatic spinal tumors are different, the respective associated costs and morbidities associated with those treatments likely vary. This study compares the direct costs and 90-day readmission rates between the resection of extradural metastatic and primary spinal tumors. The factors associated with cost and readmission are identified.

METHODS

Adults (age 18 years or older) who underwent the resection of spinal tumors between 2008 and 2013 were included in the study. Patients with intradural tumors were excluded. The direct costs of index hospitalization and 90-day readmission hospitalization were evaluated. The direct costs were compared between patients who were treated surgically for primary and metastatic spinal tumors. The independent factors associated with costs and readmissions were identified using multivariate analysis.

RESULTS

A total of 181 patients with spinal tumors were included (63 primary and 118 metastatic tumors). Overall, the mean index hospital admission cost for the surgical management of spinal tumors was $52,083. There was no significant difference in the cost of hospitalization between primary ($55,801) and metastatic ($50,098) tumors (p = 0.426). The independent factors associated with higher cost were male sex (p = 0.032), preoperative inability to ambulate (p = 0.002), having more than 3 comorbidities (p = 0.037), undergoing corpectomy (p = 0.021), instrumentation greater than 7 levels (p < 0.001), combined anterior-posterior approach (p < 0.001), presence of a perioperative complication (p < 0.001), and longer hospital stay (p < 0.001). The perioperative complication rate was 21.0%. Of this cohort, 11.6% of patients were readmitted within 90 days, and the mean hospitalization cost of that readmission was $20,078. Readmission rates after surgical treatment for primary and metastatic tumors were similar (11.1% vs 11.9%, respectively) (p = 0.880). Prior hospital stay greater than 15 days (OR 6.62, p = 0.016) and diagnosis of lung metastasis (OR 52.99, p = 0.007) were independent predictors of readmission.

CONCLUSIONS

Primary and metastatic spinal tumors are comparable with regard to the direct costs of the index surgical hospitalization and readmission rate within 90 days. The factors independently associated with costs are related to preoperative health status, type and complexity of surgery, and postoperative course.