Pitfalls of calculating hospital readmission rates based on nonvalidated administrative data sets

Retrospective Analysis of Causes and Risk Factors of 30-Day Readmission After Spine Surgery for Thoracolumbar Trauma

STUDY DESIGN

Retrospective Case Series.

OBJECTIVE

This study aims to evaluate readmission rates, risk factors, and reason for unplanned 30-day readmissions after thoracolumbar spine trauma surgery.

METHODS

A retrospective chart review was conducted for patients undergoing operative treatment for thoracic or lumbar trauma with open or minimally invasive surgical approach at a Level 1 urban trauma center. Patients were divided into two groups based on 30-day readmission status. Reason for readmission, reoperation rates, injury type, trauma severity, and incidence of polytrauma were compared between the two groups.

RESULTS

A total of 312 patients, 69.9% male with an average age of 47 ± 19 years were included. The readmitted group included 16 patients (5.1%) of which 9 (56%) were readmitted for medical complications and 7 for surgical complications. Wound complications (31.3% of readmissions) were the most common cause of readmission, followed by non-wound related sepsis (18.9% of readmissions). A total of 6 patients (37.5%) required reoperation; 2 instrumentation failures underwent revision surgery, and 4 wound complications underwent irrigation and debridement. Patients with higher Injury Severity Scale (ISS) were more likely to be readmitted (27.8% vs 22.1%, P = .045). Concomitant lower limb surgery increased odds of readmission (OR, 4.40; 95% CI, 1.10-17.83; P = .037).

CONCLUSION

Spine trauma 30-day readmission rate was 5.1%, comparable to those reported in the elective spine surgery literature. Readmitted patients were more likely to sustain concomitant operative lower limb trauma. Wound complications were the most common cause of readmission, and almost half of the patients were readmitted due to surgery-related complications.

The Relation of Surgical Procedures and Diagnosis Groups to Unplanned Readmission in Spinal Neurosurgery: A Retrospective Single Center Study

Background: Unplanned readmission has gained increasing interest as a quality marker for inpatient care, as it is associated with patient mortality and higher economic costs. Spinal neurosurgery is characterized by a lack of epidemiologic readmission data. The aim of this study was to identify causes and predictors for unplanned readmissions related to index diagnoses and surgical procedures. Methods: In this study, from 2015 to 2017, spinal neurosurgical procedures were recorded for surgical and non-surgical treated patients. The main reasons for an unplanned readmission within 30 days following discharge were identified. Multivariate logarithmic regression revealed predictors of unplanned readmission. Results: A total of 1172 patient records were examined, of which 4.27% disclosed unplanned readmissions. Among the surgical patients, the readmission rate was 4.06%, mainly attributable to surgical site infections, while it was 5.06% for the non-surgical patients, attributable to uncontrolled pain. A night-time surgery presented as the independent predictive factor. Conclusion: In the heterogeneous group of spinal neurosurgical patients, stratification into diagnostic groups is necessary for statistical analysis. Degenerative lumbar spinal stenosis and spinal abscesses are mainly affected by unplanned readmission. The surgical procedure dorsal root ganglion stimulation is an independent predictor of unplanned re-hospitalizations, as is the timing of surgery.

Development and validation of prediction scores for nosocomial infections, reoperations, and adverse events in the daily clinical setting of neurosurgical patients with cerebral and spinal tumors

OBJECTIVE

Various quality indicators are currently under investigation, aiming at measuring the quality of care in neurosurgery; however, the discipline currently lacks practical scoring systems for accurately assessing risk. The aim of this study was to develop three accurate, easy-to-use risk scoring systems for nosocomial infections, reoperations, and adverse events for patients with cerebral and spinal tumors.

METHODS

The authors developed a semiautomatic registry with administrative and clinical data and included all patients with spinal or cerebral tumors treated between September 2017 and May 2019. Patients were further divided into development and validation cohorts. Multivariable logistic regression models were used to develop risk scores by assigning points based on β coefficients, and internal validation of the scores was performed.

RESULTS

In total, 1000 patients were included. An unplanned 30-day reoperation was observed in 6.8% of patients. Nosocomial infections were documented in 7.4% of cases and any adverse event in 14.5%. The risk scores comprise variables such as emergency admission, nursing care level, ECOG performance status, and inflammatory markers on admission. Three scoring systems, NoInfECT for predicting the incidence of nosocomial infections (low risk, 1.8%; intermediate risk, 8.1%; and high risk, 26.0% [p < 0.001]), LEUCut for 30-day unplanned reoperations (low risk, 2.2%; intermediate risk, 6.8%; and high risk, 13.5% [p < 0.001]), and LINC for any adverse events (low risk, 7.6%; intermediate risk, 15.7%; and high risk, 49.5% [p < 0.001]), showed satisfactory discrimination between the different outcome groups in receiver operating characteristic curve analysis (AUC ≥ 0.7).

CONCLUSIONS

The proposed risk scores allow efficient prediction of the likelihood of adverse events, to compare quality of care between different providers, and further provide guidance to surgeons on how to allocate preoperative care.

The impact of craniotomy for brain tumor case volume on patient safety indicators and in-hospital mortality

OBJECTIVES

The relationship between outcomes, patient safety indicators and volume has been well established in patient's undergoing craniotomy for brain tumor. However, the determination of "high" and "low" volume centers have been subjectively derived. We present a paper with a novel method of objectively determining "high" volume centers for craniotomy for brain tumor.

METHODS

Patients from 2002 to 2011 were identified in the Nationwide Inpatient Sample database using ICD-9 codes related to craniotomy for brain tumor. Primary endpoints of interest were hospital PSI event rate, in-hospital mortality rate, observed-to-expected PSI event ratio, and O/E in-hospital mortality ratio. Using a zero-inflated gamma model analysis and a cutpoint analysis we determined the volume threshold between and "high" and "low" volume hospitals. We then completed an analysis using this determined threshold to look at PSI events and mortality as they relate to "high" volume and "low" volume hospitals.

RESULTS

12.4 % of hospitals were categorized as good performers using O/E ratios. Regarding in-hospital mortality, 16.8 % were good performers. Using the above statistical analysis the threshold to define high vs. low volume centers was determined to be 27 craniotomies. High volume centers had significantly lower O/E ratios for both PSI and mortality events. The PSI O/E ratio was reduced 55 % and mortality O/E ratio reduced 73 % at high volume centers as defined by our analysis.

CONCLUSIONS

Patients treated at institutions performing >27 craniotomies per year for brain tumors have a lower likelihood of PSI events and decreased in-hospital morbidity and mortality.

Unplanned Readmissions after Spine Surgery: A Single-Center Prospective Analysis of a 90-Day Model in 2,860 Cases

Study design

Prospective study.

Purpose

During the last decades, an emergence of unplanned readmissions has been shown to be a useful tool to gage the healthcare quality and hospital performance. Previous studies were limited by their retrospective designs based on database information and short-term 30-day follow-up intervals. We analyzed the incidence and causes for unplanned readmissions following spine surgery at a 90-day interval and the difference at 30-, 31–60-, and 61–90-day intervals after discharge. Additionally, we assessed total bed-days lost and the economic impact of readmissions and probable risk factors.

Overview of Literature

Recent reports on readmission rates suggested the contribution of this parameter for the assessment of healthcare quality.

Methods

A prospective analysis of 2,860 admissions was performed over 1 year in a tertiary care orthopedic hospital. All unscheduled readmissions following spine surgery within 90 days of discharge were included, irrespective of type or location of surgery. Polytrauma, primary osseous infections, and planned readmissions were excluded.

Results

Our readmission rate was 3.32% (95/2,860). Leading readmission causes were surgical site infections (SSIs) accounting for 44.21% (n=42; superficial, 23; deep, 11; organ and space, 8), followed by aseptic pain 31.58% (n=30) and medical causes 13.68% (n=13). Though 86.95% of superficial SSIs occurred within 30 days, 21.1% of deep SSIs occurred beyond 30 days. During the 30–90-day interval, 33.68% of readmissions occurred. The financial burden amounted to 41,93,660 Indian Rupees, and the mean bed-days lost was 7.33 per readmission. Hospital stay ≥10 days, health insurance, and comorbid illnesses (diabetes, hypertension, and liver disease) were associated with readmissions (p <0.05).

Conclusions

Our study showed that SSIs and aseptic pain were the leading causes of readmissions at 90 days after spine surgery. Limiting the analysis to 30-day readmissions as in previous studies would lead to failure in the identification of more severe complications like deep SSIs. Continued vigilance, particularly for patients with predisposing factors, could help alleviate the financial burden.

Hospital Length of Stay and Readmission Rate for Neurosurgical Patients

BACKGROUND

Hospital readmission rate has become a major indicator of quality of care, with penalties given to hospitals with high rates of readmission. At the same time, insurers are increasing pressure for greater efficiency and reduced costs, including decreasing hospital lengths of stay (LOS).

OBJECTIVE

To analyze the authors' service to determine if there is a relationship between LOS and readmission rates.

METHODS

Records of patients admitted to the authors' institution from October 2007 through June 2014 were analyzed for several data points, including initial LOS, readmission occurrence, admitting and secondary diagnoses, and discharge disposition.

RESULTS

Out of 9409 patient encounters, there were 925 readmissions. Average LOS was 6 d. Univariate analysis indicated a higher readmission rate with more diagnoses upon admission (P < .001) and an association between insurance type and readmission (P < .001), as well as decreasing average yearly LOS (P = .0045). Multivariate analysis indicated statistically significant associations between longer LOS (P = .03) and government insurance (P < .01).

CONCLUSION

A decreasing LOS over time has been associated with an increasing readmission rate at the population level. However, at the individual level, a prolonged LOS was associated with a higher risk of readmission. This was attributed to patient comorbidities. However, this increasing readmission rate may represent many factors including patients' overall health status. Thus, the rate of readmission may represent a burden of illness rather than a valid metric for quality of care.

Causes and Timing of Unplanned 90-day Readmissions Following Spine Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to evaluate the causes, timing, and factors associated with unplanned 90-day readmissions following elective spine surgery.

SUMMARY OF BACKGROUND DATA

Unplanned readmissions after spine surgery are costly and an important determinant of the value of care. Several studies using database information have reported on rates and causes of readmission. However, these often lack the clinical detail and actionable data necessary to guide early postdischarge interventions.

METHODS

Patients undergoing elective spine surgery for degenerative disease at a major medical center were enrolled in a prospective longitudinal registry. Patient and surgery-specific characteristics, baseline, and 3-month patient-reported outcomes were prospectively recorded. Readmissions were reviewed retrospectively to establish the reason and time to readmission. A multivariable Cox proportional hazard model was created to analyze the independent effects of several factors on readmission.

RESULTS

Of 2761 patients with complete 3-month follow-up, 156 had unplanned 90-day readmissions (5.6%). The most common reason was surgery-related (52%), followed by medical complications (38%) and pain (10%). Pain readmissions presented with a median time of 6 days. Medical readmissions presented at 12 days. Surgical complications presented at various times with wound complications at 6 days, cerebrospinal fluid leaks at 12 days, surgical site infections at 23 days, and surgical failure at 38 days. A history of myocardial infarction, osteoporosis, higher baseline leg and arm pain scores, longer operative duration, and lumbar surgery were associated with readmission.

CONCLUSION

Nearly half of all unplanned 90-day readmissions were because of pain and medical complications and occurred with a median time of 6 and 12 days, respectively. The remaining 52% of readmissions were directly related to surgery and occurred at various times depending on the specific reason. This timeline for pain and medical readmissions represents an opportunity for targeted postdischarge interventions to prevent unplanned readmissions following spine surgery.

LEVEL OF EVIDENCE

3.

Incidence and Risk Factors for 30-Day Unplanned Readmissions After Elective Posterior Lumbar Fusion

STUDY DESIGN

Retrospective study of prospectively collected data.

OBJECTIVE

To perform a multiinstitutional assessment on the incidence and risk factors for unplanned readmissions following elective posterior lumbar fusion (PLF) surgery.

SUMMARY OF BACKGROUND DATA

Understanding what may drive rehospitalizations is a necessary step toward higher quality care. Identifying risk factors for unplanned readmission is especially important for elective PLF, which is a common procedure that is known to be associated with significant adverse events.

METHODS

Adult patients undergoing PLF were identified using current procedure terminology (CPT) from the American College of Surgeons National Surgical Quality Improvement Program. Both descriptive and comparative statistics were performed for patient characteristics, clinical factors, and postoperative complications. Subsequently, a step-wise multivariate logistic regression was employed.

RESULTS

Of the 2301 patients who met inclusion criteria for this study, 117 were unplanned readmissions (5.1%). These occurred at a mean of 15.9 days (range: 3-30 days) after surgery. The risk-adjusted analysis revealed that bleeding disorder (odds ratio, OR = 2.8, confidence intervals, CI = 1.0-7.6, P = 0.043), insulin dependent diabetes (OR = 2.5, CI = 1.4-4.4, P = 0.004), and total length of stay > 5 days (OR = 1.8, CI = 1.2-2.8, P = 0.009) were independent predictors for unplanned readmission. Significant postoperative complications included wound complications (OR = 27.6, CI = 13.9-54.8, P < 0.0001), pulmonary embolism and/or deep vein thrombosis/thrombophlebitis (OR = 11.9, CI = 5.0-28.5, P < 0.0001), sepsis (OR = 8.5, CI = 2.3-32.1, P = 0.002), and urinary tract infections (OR = 2.4, CI = 0.9-6.9, P = 0.094).

CONCLUSION

The unplanned readmission rate for patients undergoing PLF was low, but this study's findings of potentially modifiable risk factors suggest that substantial improvement with this quality metric is possible.

LEVEL OF EVIDENCE

N/A.

Impact of Definition and Timeframe on Capturing Surgery-Related Readmissions After Primary Joint Arthroplasty

BACKGROUND

Readmission rate has emerged as an important metric to measure quality, but varying definitions and timeframes are used. We aimed to evaluate the impact of different readmission definitions (postoperative vs postdischarge) and timeframes (30 vs 90-day) on capturing surgery-related readmissions after primary total joint arthroplasty.

METHODS

Patients who underwent primary total hip or knee arthroplasty between January 1, 2013 and December 31, 2015 were included. The electronic medical records of readmitted patients were reviewed to determine whether a surgery-related event was most responsible for readmission. The performances of 4 definition-timeframe combinations in capturing surgery-related readmissions were evaluated.

RESULTS

A total of 2586 patients were included. Using both postoperative and postdischarge definitions, there were no differences in the proportion of readmissions that were surgery-related when comparing 30 and 90-day timeframes (postoperative: 71% vs 60%, P = .118; postdischarge: 68% vs 60%, P = .219). Greater proportion of readmissions between days 0 and 30 were for surgery-related reasons compared with readmissions between days 31 and 90 using both postoperative and postdischarge definitions (postoperative: 71% vs 47%, P = .005; postdischarge: 68% vs 49%, P = .022). Among 104 patients readmitted for surgery-related reasons within 1 year of discharge, 52% were readmitted within 30 days of surgery compared with 79% within 90 days (P < .001). Similarly, 53% and 81% of readmissions were captured by the 30 and 90-day postdischarge definitions, respectively (P < .001).

CONCLUSION

A 90-day timeframe is superior in capturing surgery-related readmissions after total joint arthroplasty. Important Total hip and knee arthroplasty adverse events may be missed using a 30-day timeframe.

Unplanned readmission within 90 days after pediatric neurosurgery

OBJECTIVE Readmission and return to operating room after surgery are increasingly being used as a proxy for quality of care. Nearly 60% of these readmissions are unplanned, which translates into billions of dollars in health care costs. The authors set out to analyze the incidence of readmission at their center, to define causes of unplanned readmission, and to determine the preoperative and surgical variables associated with readmissions following pediatric neurosurgery. METHODS A total of 536 children who underwent operations for neurosurgical diagnoses between 2012 and 2015 and who were later readmitted were included in the final analysis. Unplanned readmissions were defined to have occurred as a result of complications within 90 days after index surgery. Patient records were retrospectively reviewed to determine the primary diagnosis, surgery indication, and cause of readmission and return to operating room. The cost for index hospitalization, readmission episode, and total cost were derived based on the charges obtained from administrative data. Bivariate and multivariable analyses were conducted. RESULTS Of 536 patients readmitted in total, 17.9% (n = 96) were readmitted within 90 days. Of the overall readmissions, 11.9% (n = 64) were readmitted within 30 days, and 5.97% (n = 32) were readmitted between 31 and 90 days. The median duration between discharge and readmission was 20 days (first quartile [Q1]: 9 days, third quartile [Q3]: 36 days). The most common reason for readmission was shunt related (8.2%, n = 44), followed by wound infection (4.7%, n = 25). In the risk-adjusted multivariable logistic regression model for total 90-day readmission, patients with the following characteristics: younger age (p = 0.001, OR 0.886, 95% CI 0.824-0.952); "other" (nonwhite, nonblack) race (p = 0.024, OR 5.49, 95% CI 1.246-24.2); and those born preterm (p = 0.032, OR 2.1, 95% CI 1.1-4.12) had higher odds of being readmitted within 90 days after discharge. The total median cost for patients undergoing surgery in this study cohort was $11,520 (Q1: $7103, Q3: $19,264). For the patients who were readmitted, the median cost for a readmission episode was $8981 (Q1: $5051, Q3: $18,713). CONCLUSIONS Unplanned 90-day readmissions in pediatric neurosurgery are primarily due to CSF-related complications. Patients with the following characteristics: young age at presentation; "other" race; and children born preterm have a higher likelihood of being readmitted within 90 days after surgery. The median cost was > $8000, which suggests that the readmission episode can be as expensive as the index hospitalization. Clearly, readmission reduction has the potential for significant cost savings in pediatric neurosurgery. Future efforts, such as targeted education related to complication signs, should be considered in the attempt to reduce unplanned events. Given the single-center, retrospective study design, the results of this study are primarily applicable to this population and cannot necessarily be generalized to other institutions without further study.

90-day Readmission After Lumbar Spinal Fusion Surgery in New York State Between 2005 and 2014: A 10-year Analysis of a Statewide Cohort

MINI: We assessed 90-day readmission and evaluated risk factors associated with readmission after lumbar spinal fusion surgery in New York State. The overall 90-day readmission rate was 24.8%. Age, sex, race, insurance, procedure, number of operated spinal levels, health service area, and comorbidities are major risk factors for 90-day readmission.

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to assess 90-day readmission and evaluate risk factors associated with readmission after lumbar fusion in New York State.

SUMMARY OF BACKGROUND DATA

Readmission is becoming an important metric for quality and efficiency of health care. Readmission and its predictors following spine surgery are overall poorly understood and limited evidence is available specifically in lumbar fusion.

METHODS

The New York Statewide Planning and Research Cooperative System (SPARCS) was utilized to capture patients undergoing lumbar fusion from 2005 to 2014. Temporal trend of 90-day readmission was assessed using Cochran-Armitage test. Logistic regression was used to examine predictors associated with 90-day readmission.

RESULTS

There were 86,869 patients included in this cohort study. The overall 90-day readmission rate was 24.8%. On a multivariable analysis model, age (odds ratio [OR] comparing ≥75 versus <35 years: 1.24, 95% confidence interval [CI]: 1.13-1.35), sex (OR female to male: 1.19, 95% CI: 1.15-1.23), race (OR African-American to white: 1.60, 95% CI: 1.52-1.69), insurance (OR Medicaid to Medicare: 1.42, 95% CI: 1.33-1.53), procedure (OR comparing thoracolumbar fusion, combined [International Classification of Disease, Ninth Revision, ICD-9: 81.04] to posterior lumbar interbody fusion/transforaminal lumbar spinal fusion [ICD-9: 81.08]: 2.10, 95% CI: 1.49-2.97), number of operated spinal levels (OR comparing four to eight vertebrae to two to three vertebrae: 2.39, 95% CI: 2.07-2.77), health service area ([HSA]; OR comparing Finger Lakes to New York-Pennsylvania border: 0.67, 95% CI: 0.61-0.73), and comorbidity, i.e., coronary artery disease (OR: 1.26, 95% CI: 1.19-1.33) were significantly associated with 90-day readmission. Directions of the odds ratios for these factors were consistent after stratification by procedure type.

CONCLUSION

Age, sex, race, insurance, procedure, number of operated spinal levels, HSA, and comorbidities are major risk factors for 90-day readmission. Our study allows risk calculation to determine high-risk patients before undergoing spinal fusion surgery to prevent early readmission, improve quality of care, and reduce health care expenditures.

LEVEL OF EVIDENCE

3.

Impact of Discharge Disposition on 30-Day Readmissions Following Elective Spine Surgery

BACKGROUND

Readmissions are a significant economic burden on the health care system and increasingly being utilized as a metric of quality. Patients discharged to home vs an inpatient facility have different characteristics, which might influence the readmissions following spine surgery.

OBJECTIVE

To determine the effect of discharge disposition on readmission rates and causes of readmission after spine surgery.

METHODS

Patients enrolled in a prospective registry and undergoing elective spine surgery were analyzed. Readmissions (30 d), demographic, clinical variables, and baseline patient-reported outcomes were recorded. Patients were dichotomized as discharged home vs inpatient facility.

RESULTS

Of total 1631 patients, 1444 (89%) patients were discharged home and 187 (11%) discharged to an inpatient facility. Sixty-five (4%) patients were readmitted at 30 d. There was no significant difference in readmissions between patients discharged to a facility 10 (5%) vs home 55 (4%; P = .210). In a multivariable analysis, adjusting for all the comorbidities, the discharge destination was not associated with readmission within 30 d. The medical complications (80%) were the most common cause of readmission in those discharged to a facility. Patients discharged home had significantly higher readmissions related to surgical wound issues (67%; P = .034).

CONCLUSION

Despite the older age and higher comorbidities in patients discharged to an inpatient facility, the proportion of readmissions was comparable to those discharged home. Patients discharged home had a higher proportion of readmissions related to surgical wound complications and those discharged to facility had higher readmissions associated with medical complications. Understanding causes of readmission based on discharge destination may allow targeted intervention to reduce the readmission rates following spine surgery.

Risk factors for 30-day reoperation and 3-month readmission: analysis from the Quality and Outcomes Database lumbar spine registry

OBJECTIVE

The aim of this paper was to use a prospective, longitudinal, multicenter outcome registry of patients undergoing surgery for lumbar degenerative disease in order to assess the incidence and factors associated with 30-day reoperation and 90-day readmission.

METHODS

Prospectively collected data from 9853 patients from the Quality and Outcomes Database (QOD; formerly known as the N2QOD [National Neurosurgery Quality and Outcomes Database]) lumbar spine registry were retrospectively analyzed. Multivariate binomial regression analysis was performed to identify factors associated with 30-day reoperation and 90-day readmission after surgery for lumbar degenerative disease. A subgroup analysis of Medicare patients stratified by age (< 65 and ≥ 65 years old) was also performed. Continuous variables were compared using unpaired t-tests, and proportions were compared using Fisher’s exact test.

RESULTS

There was a 2% reoperation rate within 30 days. Multivariate analysis revealed prolonged operative time during the index case as the only independent factor associated with 30-day reoperation. Other factors such as preoperative diagnosis, body mass index (BMI), American Society of Anesthesiologists (ASA) class, diabetes, and use of spinal implants were not associated with reoperations within 30 days. Medicare patients < 65 years had a 30-day reoperation rate of 3.7%, whereas those ≥ 65 years had a 30-day reoperation rate of 2.2% (p = 0.026). Medicare beneficiaries younger than 65 years undergoing reoperation within 30 days were more likely to be women (p = 0.009), have a higher BMI (p = 0.008), and have higher rates of depression (p < 0.0001). The 90-day readmission rate was 6.3%. Multivariate analysis demonstrated that higher ASA class (OR 1.46 per class, 95% CI 1.25–1.70) and history of depression (OR 1.27, 95% CI 1.04–1.54) were factors associated with 90-day readmission. Medicare beneficiaries had a higher rate of 90-day readmissions compared with those who had private insurance (OR 1.43, 95% CI 1.17–1.76). Medicare patients < 65 years of age were more likely to be readmitted within 90 days after their index surgery compared with those ≥ 65 years (10.8% vs 7.7%, p = 0.017). Medicare patients < 65 years of age had a significantly higher BMI (p = 0.001) and higher rates of depression (p < 0.0001).

CONCLUSIONS

In this analysis of a large prospective, multicenter registry of patients undergoing lumbar degenerative surgery, multivariate analysis revealed that prolonged operative time was associated with 30-day reoperation. The authors found that factors associated with 90-day readmission included higher ASA class and a history of depression. The 90-day readmission rates were higher for Medicare beneficiaries than for those who had private insurance. Medicare patients < 65 years of age were more likely to undergo reoperation within 30 days and to be readmitted within 90 days after their index surgery.

Readmission After Aneurysmal Subarachnoid Hemorrhage: A Nationwide Readmission Database Analysis

BACKGROUND AND PURPOSE

The goal of this nationwide study is to evaluate the suitability of readmission as a quality indicator in the aneurysmal subarachnoid hemorrhage (SAH) population.

METHODS

Patients with aneurysmal SAH were extracted from the Nationwide Readmission Database (2013). Multivariable Cox proportional hazard regression was used to evaluate predictors of a 30-day readmission, and multivariable linear regression was used to analyze the association of hospital readmission rates with hospital mortality rates. Predictors screened included patient demographics, comorbidities, severity of SAH, complications from the SAH hospitalization, and hospital characteristics.

RESULTS

The 30-day readmission rate was 10.2% (n=346) among the 3387 patients evaluated, and the most common reasons for readmission were neurological, hydrocephalus, infectious, and venous thromboembolic complications. Greater number of comorbidities, increased severity of SAH, and discharge disposition other than to home were independent predictors of readmission (P≤0.03). Although hydrocephalus during the SAH hospitalization was associated with readmission for the same diagnosis, other readmissions were not associated with having sustained the same complication during the SAH hospitalization. Hospital mortality rate was inversely associated with hospital SAH volume (P=0.03) but not significantly associated with hospital readmission rate; hospital SAH volume was also not associated with SAH readmissions.

CONCLUSIONS

In this national analysis, readmission was primarily attributable to new medical complications in patients with greater comorbidities and severity of SAH rather than exacerbation of complications from the SAH hospitalization. Additionally, hospital readmission rates did not correlate with other established quality metrics. Therefore, readmission may be a suboptimal quality indicator in the SAH population.

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.

Predictors of extended length of stay, discharge to inpatient rehab, and hospital readmission following elective lumbar spine surgery: introduction of the Carolina-Semmes Grading Scale

OBJECTIVE Extended hospital length of stay (LOS), unplanned hospital readmission, and need for inpatient rehabilitation after elective spine surgery contribute significantly to the variation in surgical health care costs. As novel payment models shift the risk of cost overruns from payers to providers, understanding patient-level risk of LOS, readmission, and inpatient rehabilitation is critical. The authors set out to develop a grading scale that effectively stratifies risk of these costly events after elective surgery for degenerative lumbar pathologies. METHODS The Quality and Outcomes Database (QOD) registry prospectively enrolls patients undergoing surgery for degenerative lumbar spine disease. This registry was queried for patients who had undergone elective 1- to 3-level lumbar surgery for degenerative spine pathology. The association between preoperative patient variables and extended postoperative hospital LOS (LOS ≥ 7 days), discharge status (inpatient facility vs home), and 90-day hospital readmission was assessed using stepwise multivariate logistic regression. The Carolina-Semmes grading scale was constructed using the independent predictors for LOS (0-12 points), discharge to inpatient facility (0-18 points), and 90-day readmission (0-6 points), and its performance was assessed using the QOD data set. The performance of the grading scale was then confirmed separately after using it in 2 separate neurosurgery practice sites (Carolina Neurosurgery & Spine Associates [CNSA] and Semmes Murphey Clinic). RESULTS A total of 6921 patients were analyzed. Overall, 290 (4.2%) patients required extended LOS, 654 (9.4%) required inpatient facility care/rehabilitation on hospital discharge, and 474 (6.8%) were readmitted to the hospital within 90 days postdischarge. Variables that remained as independently associated with these unplanned events in multivariate analysis included age ≥ 70 years, American Society of Anesthesiologists Physical Classification System class > III, Oswestry Disability Index score ≥ 70, diabetes, Medicare/Medicaid, nonindependent ambulation, and fusion. Increasing point totals in the Carolina-Semmes scale effectively stratified the incidence of extended LOS, discharge to facility, and readmission in a stepwise fashion in both the aggregate QOD data set and when subsequently applied to the CNSA/Semmes Murphey practice groups. CONCLUSIONS The authors introduce the Carolina-Semmes grading scale that effectively stratifies the risk of prolonged hospital stay, need for postdischarge inpatient facility care, and 90-day hospital readmission for patients undergoing first-time elective 1- to 3-level degenerative lumbar spine surgery. This grading scale may be helpful in identifying patients who may require additional resource utilization within a global period after surgery.

Thirty-Day Readmission Rates Following Deep Brain Stimulation Surgery

BACKGROUND: Deep brain stimulation (DBS) has emerged as a safe and efficacious surgical intervention for several movement disorders; however, the 30-day all-cause readmission rate associated with this procedure has not previously been documented.

OBJECT: To perform a retrospective cohort study to estimate the 30-day all-cause readmission rate associated with DBS.

METHODS: We reviewed medical records of patients over the age of 18 who underwent DBS surgery at Pennsylvania Hospital of the University of Pennsylvania between 2009 and 2014. We identified patients who were readmitted to an inpatient medical facility within 30 days from their initial discharge.

RESULTS: Over the study period, 23 (6.6%) of 347 DBS procedures resulted in a readmission to the hospital within 30 days. Causes of readmission were broadly categorized into surgery-related (3.7%): intracranial lead infection (0.6%), battery-site infection (0.6%), intracranial hematoma along the electrode tract (0.6%), battery-site hematoma (0.9%), and seizures (1.2%); and nonsurgery-related (2.9%): altered mental status (1.8%), nonsurgical-site infections (0.6%), malnutrition and poor wound healing (0.3%), and a pulse generator malfunction requiring reprogramming (0.3%). Readmissions could be predicted by the presence of medical comorbidities (P &lt; .001), but not by age, gender, or length of stay (Ps &gt; .15).

CONCLUSION: All-cause 30-day readmission for DBS is 6.6%. This compares favorably to previously studied neurosurgical procedures. Readmissions frequently resulted from surgery-related complications, particularly infection, seizures, and hematomas, and were significantly associated with the presence of medical comorbidities (P &lt; .001).

Unplanned 90-day readmissions in a specialty orthopaedic unit-A prospective analysis of consecutive 12729 admissions

INTRODUCTION

Unplanned readmissions are an undesirable and expensive outcome of clinical practice. Previous reported literature is limited by retrospective study designs and 30 day study intervals. We analyzed causes for 90-day unplanned readmission, temporal occurrence of major causes, possible predisposing factors, bed days lost and economic impact.

MATERIALS & METHODS

A prospective analysis of 12729 admissions was performed over 1 year in an Orthopaedic unit. Consecutive readmissions for unplanned circumstances within 90-days of discharge following the index procedure were included. Open injuries, polytrauma, primary osseous infections and planned readmissions were excluded.

RESULTS

We noted an overall readmission rate of 2.07% and subspecialty rate of 1.43%, 3.32%, 2.9% in trauma, spine and total joint arthroplasty (TJA) respectively. The leading cause was wound complications accounting for 49.62%, followed by medical causes (trauma -18.37%; TJA -27.5%) and aseptic pain (spine-31.6%). Though 87.1% of superficial surgical site infections (SSIs) occurred within 30 days, 21.1%, 41.2% and 60% of the deep SSIs in spine, trauma and TJA respectively occurred beyond 30 days. The financial burden amounted to INR 1,01,55,770 and mean bed days lost was 7.6 per readmission. Age ≥70 years, indoor-stay ≥10 days, health insurance and co-morbid illnesses were associated with readmissions (p < 0.05).

CONCLUSIONS

Our study showed that limiting analysis to 30 day unplanned readmissions would lead to failure in identification of 34.85% of readmissions especially deep surgical site infections in TJA and trauma.

Factors predicting venous thromboembolism after spine surgery

BACKGROUND

A meta-analysis was performed to explore predicted factors of venous thromboembolism (VTE) after surgery in the treatment for spine degeneration diseases.

SUMMARY OF BACKGROUND DATA

Many scholars have focused on VTE after spine surgery, but as for the risk factors of VTE have not reached a consensus.

METHODS

An extensive search of literature, "spine or spinal," "degeneration," "after surgery or postoperation," and "venous thromboembolism" as key words, was performed in PubMed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases. The following variables were extracted: wearing elastic stocking, hypertension (HT), heart disease, diabetes, drinking, anticoagulant therapy, walking disability preoperation, smoking, sex, age, surgical duration, fusion versus nonfusion (lumbar fusion vs lumbar discectomy), surgical site (cervical vs lumbar), blood loss, and body mass index. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

A total of 12 studies were identified, including 34,597 patients of whom 624 patients had VTE, and the incidence of VTE was 2% in all patients who underwent spine surgery. The incidence of VTE for Asian patients was 7.5%, compared with 1% VTE for Occidental patients; the difference was significant (P < 0.0001). The pooled analysis showed that there were significant differences regarding wearing elastic stocking (odds ratio [OR] = 11.71, 95% confidence interval [CI] [1.46, 94.00], P = 0.02), walking disability preoperation (OR = 4.80, 95% CI [2.53, 9.12], P < 0.00001), surgical site (lumbar surgery) (OR = 0.23, 95% CI [0.20, 0.27], P < 0.00001), HT (OR = 1.59, 95% CI [1.21, 2.10], P = 0.001), and diabetes (OR = 2.12, 95% CI [1.09, 4.10], P = 0.03). However, there were no significant differences in blood loss, heart disease, smoking, sex, surgical duration, body mass index, surgical duration, anticoagulant therapy, wearing elastic stocking, fusion versus nonfusion, drinking, and age (all P > 0.05).

CONCLUSIONS

Based on our meta-analysis, Asian patients, patients with walking disability preoperation, patients wearing elastic stocking, patients having undergone lumbar surgery, patients with a history of HT, and patients experiencing diabetes have a higher incidence of VTE after spine surgery.

Risk Factors for 30-Day Unplanned Readmission and Major Perioperative Complications After Spine Fusion Surgery in Adults: A Review of the National Surgical Quality Improvement Program Database

STUDY DESIGN

Retrospective review of a prospective cohort.

OBJECTIVE

The aim of the study was to determine the patient characteristics and surgical procedure factors related to increased rates of 30-day unplanned readmission and major perioperative complications after spinal fusion surgery, and the association between unplanned readmission and major complications.

SUMMARY OF BACKGROUND DATA

Reducing unplanned readmissions can reduce the cost of healthcare. Payers are implementing penalties for 30-day readmissions after discharge. There is limited data regarding the current rates and risk factors for unplanned readmission and major complications related to spinal fusion surgery.

METHODS

Spine fusion patients were identified using the 2012 and 2013 American College of Surgeons National Surgical Quality Improvement Program Participant User File. Rates of readmissions within 30 days after spine fusion surgery were calculated using the person-years method. Cox proportional hazards models were used to assess the independent associations of spine surgical procedure types, diagnoses, patient profiles, and major perioperative complications with unplanned related readmissions. Independent risk factors for major complications were assessed by multivariable logistic regression.

RESULTS

Of the 18,602 identified patients, there was a 5.2% overall major perioperative complication rate. There was a rate of 4.4% per 30 person-days for unplanned readmissions related to index surgery. Independent risk factors for both readmissions and major perioperative complications included combined anterior and posterior surgery, diagnosis of solitary tumor, older age, and higher American Society of Anesthesiologists class. Patients with deep/organ surgical site infection carried higher risk of having unplanned readmission, followed by pulmonary embolism, acute renal failure, and stroke/cerebral vascular accident with neurological deficit.

CONCLUSION

This study provides benchmark rates of 30-day readmission based on diagnosis and procedure codes from a high-quality database for adult spinal fusion patients and showed increased rates of 30-day unplanned readmission and major perioperative complications for patients with specific risk factors. Targeted preoperative planning on modifiable risk factors with proportional reimbursement may promote higher-quality healthcare.

LEVEL OF EVIDENCE

3.

Potentially Preventable 30-Day Hospital Readmissions at a Children's Hospital

BACKGROUND AND OBJECTIVES

Hospital readmission rates are increasingly used to assess quality. Little is known, however, about potential preventability of readmissions among children. Our objective was to evaluate potential preventability of 30-day readmissions using medical record review and interviews.

METHODS

A cross-sectional study in 305 children (<18 years old) readmitted within 30 days to a freestanding children's hospital between December 2012 and February 2013. Interviews (N = 1459) were conducted with parents/guardians, patients (if ≥13 years old), inpatient clinicians, and primary care providers. Reviewers evaluated medical records, interview summaries, and transcripts, and then rated potential preventability. Multivariate regression analysis was used to identify factors associated with potentially preventable readmission. Adjusted event curves were generated to model days to readmission.

RESULTS

Of readmissions, 29.5% were potentially preventable. Potentially preventable readmissions occurred sooner after discharge than non-potentially preventable readmissions (5 vs 9 median days; P < .001). The odds of a readmission being potentially preventable were greatest when the index admission and readmission were causally related (adjusted odds ratio [AOR]: 2.6; 95% confidence interval [CI]: 1.0-6.8) and when hospital (AOR: 16.3; 95% CI: 5.9-44.8) or patient (AOR: 7.1; 95% CI: 2.5-20.5) factors were identified. Interviews provided new information about the readmission in 31.2% of cases.

CONCLUSIONS

Nearly 30% of 30-day readmissions to a children's hospital may be potentially preventable. Hospital and patient factors are associated with potential preventability and may provide targets for quality improvement efforts. Interviews contribute important information and should be considered when evaluating readmissions.

[Readmission from orthopedic surgical site infections: an integrative review]

OBJECTIVE

Characterizing readmissions from orthopedic surgical site infections.

METHOD

An integrative review of literature in the LILACS, IBECS, MEDLINE, Cochrane, SciELO and PUBMED databases, using the descriptors Patient readmission, Wound infection, Cross infection, Orthopedic procedures, Orthopedics.

RESULTS

78 studies were identified and 10 publications were selected. Surgical site infections are the most common cause of unplanned orthopedic readmissions, representing long periods of hospitalization, new surgical procedures and high costs, and greater possibility of subsequent hospitalizations. Most significant predictors have indicated average length of hospitalization, need for intensive care, emergency status at admission, risk of death, age > 65 years, males and higher body mass index.

CONCLUSION

Readmission rates have increasingly become measures of quality and concerns about costs. New studies could involve issues related to indirect costs, specifically social and psychological costs.

What Are the 30-day Readmission Rates Across Orthopaedic Subspecialties?

BACKGROUND

The Centers for Medicare & Medicaid Services (CMS) now include hip and knee replacements in the Hospital Readmission Reduction Program. The 30-day readmission rate is an important quality metric; however, the incidence has not yet been defined across the numerous orthopaedic subspecialties. Elucidating the readmission rate for each subspecialty may indicate that certain services are being disincentivized by the CMS reimbursement program. Furthermore, the "planned" and "unplanned" definitions of readmission have not been well examined to determine their clinical relevance and representation of safe patient care. Therefore, reducing the 30-day readmission rate has become a top priority in orthopaedic quality assurance.

QUESTIONS/PURPOSES

(1) What are the 30-day readmission rates for the different orthopaedic subspecialties? (2) What are the risk factors associated with readmission within 30 days? (3) What are the causes of 30-day readmissions? (4) What is the interrater agreement among CMS, hospital, and clinician definitions of planned and unplanned readmissions?

METHODS

We retrospectively examined one tertiary care academic hospital's quality improvement database and identified 4792 discharges from the department of orthopaedics during a continuous 24-month period. Discharges were divided and analyzed according to the subspecialty of orthopaedic care. Demographics and comorbidities were extracted from the database and subjected to univariate and multivariate analysis to determine risk factors for 30-day readmission. Further chart review was conducted on all cases of 30-day readmission to identify causes. The authors' determination of planned versus unplanned was compared with two other definitions (hospital and CMS) and analyzed for agreement by using Fleiss' kappa for multiple rater.

RESULTS

The all-cause 30-day readmission rate was 4% (95% confidence interval [CI], 3.8-4.8). The unplanned readmission rate was 3% (95% CI, 2.8-3.8). After controlling for relevant confounding variables, we found that length of stay (odds ratio [OR], 1.10 per day; p < 0.001), American Society of Anesthesiologists score (OR, 1.89 per point; p < 0.001), and care under trauma (OR, 2.55; p < 0.001) or "other" (OR, 1.65; p = 0.009) as compared with joint subspecialty were associated with increased risk of readmission. Of the 160 unplanned readmissions, 93 (58%) were surgical and 67 (42%) were medical. The most common surgical cause was surgical site infection (38% of surgical readmissions) and the most common medical causes were gastrointestinal bleed, pulmonary embolus, and unrelated trauma (each 9% of medical readmissions). There was poor agreement (Fleiss' kappa = 0.120) among the three definitions of planned readmission.

CONCLUSIONS

There are important differences in the risk of readmission by subspecialty across orthopaedics and the CMS-driven disincentives may be applied unequally across these subspecialties. This could result in hospitals deemphasizing those service lines and could potentially limit access to care for the patients most in need. Avenues of readmission reduction should be further studied including telephone followup programs and outpatient management of threatened wounds. Clinical, hospital, and CMS definitions of planned readmission have poor agreement, suggesting that hospitals are being unnecessarily penalized. The CMS should develop a more clinically relevant definition of 30-day readmission to more accurately evaluate the rate of readmissions.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Complications and Rates of Subsequent Lumbar Surgery Following Lumbar Total Disc Arthroplasty and Lumbar Fusion

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To examine complications and rates of subsequent surgery following lumbar spinal fusion (LF) and lumbar total disc arthroplasty (TDA) at up to 5-year follow-up.

SUMMARY OF BACKGROUND DATA

LF is commonly used in the management of degenerative disc disease causing pain refractory to nonoperative management. Lumbar TDA was developed as an alternative to fusion with the theoretical advantage of reducing rates of adjacent segment pathology and reoperation. Most prior reports comparing these 2 interventions have come from industry-sponsored investigational device exemption trials and no large-scale administrative database comparisons exist.

METHODS

The California Office of Statewide Health Planning and Development discharge database was queried for patients aged 18 to 65 years undergoing lumbar TDA and LF for degenerative disc disease from 2004 to 2010. Patient characteristics were collected, and rates of complications and readmission were identified. Rates of repeat lumbar surgery were calculated at 90-day and 1-, 3-, and 5-year follow-up intervals.

RESULTS

A total of 52,877 patients met the inclusion criteria (LF = 50,462, TDA = 2415). Wound infections were more common following LF than TDA (1.03% vs. 0.25%, P < 0.001). Rates of subsequent lumbar surgery at 90-day and 1-year follow-up were lower with lumbar TDA than LF (90-day-TDA: 2.94% vs. LF: 4.01%, P = 0.007; 1-yr-TDA: 3.46% vs. LF: 4.78%, P = 0.009). However, there were no differences in rates of subsequent lumbar surgery between the 2 groups at 3-year and 5-year follow-up.

CONCLUSION

Lumbar TDA was associated with fewer early reoperations, though beyond 1 year, rates of reoperation were similar. Lumbar TDA may be associated with fewer acute infections, though this may be approach related and unrelated to the device itself.

LEVEL OF EVIDENCE

3.

Utility of Readmission Rates as a Quality of Care Measure and Predictors of Readmission Within 30 Days After Spinal Surgery: a Single-Center, Multivariate Analysis

STUDY DESIGN

A retrospective review.

OBJECTIVE

The aim of this study was to establish clinically relevant readmission rates that permit accurate comparisons, improve risk-stratification, and direct efforts to minimize readmissions.

SUMMARY OF BACKGROUND DATA

The 30-day hospital readmission rate is a quality of care measure that is now being used to compare hospitals in a publicly available manner.

METHODS

Records from 1187 consecutive spinal surgeries at Northwestern Memorial Hospital in 2010 were retrospectively reviewed and data were collected that described the patient, surgical procedure, hospital course, complications, and readmissions. The primary outcome of interest was readmission to the hospital within 30 days. Potential risk factors were examined for association with the outcome first via bivariate analysis, with significant predictors further examined by a multivariable model. Identified readmissions were independently reviewed by attending spinal neurosurgeons not involved with the cases to determine whether the readmissions were procedure related or procedure unrelated with respect to accepted criteria.

RESULTS

The overall readmission rate was 6.1%. Of these readmissions, 37.5% were deemed procedure related upon attending review, leading to a procedure-related readmission rate of 2.3%. Upon multivariate analysis, only 3 variables were found to be significant predictors of readmission: 2 or more patient comorbidities [odds ratio (OR) 3.72, 95% confidence interval (95% CI) 1.62-8.56], an admission to the ICU (OR 2.68, 95% CI 1.45-4.95), and each additional spinal level involved (OR 1.11, 95% CI 1.02-1.21).

CONCLUSIONS

Our study suggests that predictors for all-cause 30-day readmission following spinal procedures include number of spinal levels performed during the surgery, number of patient comorbidities present at the time of surgery, and whether the admission required an ICU stay. Future work should focus on developing best practices to modify medical risk factors and comorbidities that have the potential to decrease 30-day readmission rates.

LEVEL OF EVIDENCE

3.

Association between in-hospital adverse events and mortality for patients with brain tumors

OBJECT

The Agency for Healthcare Research and Quality patient safety indicators (PSIs) and the Centers for Medicare and Medicaid Services hospital-acquired conditions (HACs) are administrative data-based metrics. The use of these outcomes as standard performance measures has been discussed in previous studies. With the objective of determining the applicability of these events as performance metrics among patients undergoing brain tumor surgery, this study had 2 aims: 1) to evaluate the association between PSIs, HACs, and in-hospital mortality rates; and 2) to determine a correlation between hospital volume, PSIs, and HACs.

METHODS

Patients with brain tumors treated between 1998 and 2009 were captured in the Nationwide Inpatient Sample database. Hospitals were categorized into groups according to surgical volume. Associations between PSIs, HACs, and in-hospital mortality rates were studied. Factors associated with a PSI, HAC, and mortality were evaluated in a multivariate setting.

RESULTS

A total of 444,751 patients with brain tumors underwent surgery in 1311 hospitals nationwide. Of these, 7.4% of patients experienced a PSI, 0.4% an HAC, and 1.9% died during their hospitalization. The occurrence of a PSI was strongly associated with mortality. Patients were 7.6 times more likely to die (adjusted odds ratio [aOR] 7.6, CI 6.7–8.7) with the occurrence of a PSI in a multivariate analysis. Moderate to strong associations were found between HACs, PSIs, and hospital volume. Patients treated at the highest-volume hospitals compared with the lowest-volume ones had reduced odds of a PSI (aOR 0.9, CI 0.8–1.0) and HAC (aOR 0.5, CI 0.5–0.08).

CONCLUSIONS

Patient safety-related adverse events were strongly associated with in-hospital mortality. Moderate to strong correlations were found between PSIs, HACs, and hospital procedural volume. Patients treated at the highest-volume hospitals had consistently lower rates of mortality, PSIs, and HACs compared with those treated at the lowest-volume facilities.

Thirty-day readmission rates in spine surgery: systematic review and meta-analysis

OBJECT

The rate of 30-day readmissions is rapidly gaining significance as a quality metric and is increasingly used to evaluate performance. An analysis of the present 30-day readmission rate in the spine literature is needed to aid the development of policies to decrease the frequency of readmissions. The authors examine 2 questions: 1) What is the 30-day readmission rate as reported in the spine literature? 2) What study factors impact the rate of 30-day readmissions?

METHODS

This study was registered with Prospera (CRD42014015319), and 4 electronic databases (PubMed, Cochrane Library, Web of Science, and Google Scholar) were searched for articles. A systematic review and meta-analysis was performed to assess the current 30-day readmission rate in spine surgery. Thirteen studies met inclusion criteria. The readmission rate as well as data source, time from enrollment, sample size, demographics, procedure type and spine level, risk factors for readmission, and causes of readmission were extrapolated from each study.

RESULTS

The pooled 30-day readmission rate was 5.5% (95% CI 4.2%–7.4%). Studies from single institutions reported the highest 30-day readmission rate at 6.6% (95% CI 3.8%–11.1%), while multicenter studies reported the lowest at 4.7% (95% CI 2.3%–9.7%). Time from enrollment had no statistically significant effect on the 30-day readmission rate. Studies including all spinal levels had a higher 30-day readmission rate (6.1%, 95% CI 4.1%–8.9%) than exclusively lumbar studies (4.6%, 95% CI 2.5%–8.2%); however, the difference between the 2 rates was not statistically significant (p = 0.43). The most frequently reported risk factors associated with an increased odds of 30-day readmission on multivariate analysis were an American Society of Anesthesiology score of 4+, operative duration, and Medicare/Medicaid insurance. The most common cause of readmission was wound complication (39.3%).

CONCLUSIONS

The 30-day readmission rate following spinal surgery is between 4.2% and 7.4%. The range, rather than the exact result, should be considered given the significant heterogeneity among studies, which indicates that there are factors such as demographics, procedure types, and individual institutional factors that are important and affect this outcome variable. The pooled analysis of risk factors and causes of readmission is limited by the lack of reporting in most of the spine literature.

Causes of 30-day readmission after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Hospital readmission is a common but controversial quality measure increasingly used to influence hospital compensation in the US. The objective of this study was to evaluate the causes for 30-day hospital readmission following aneurysmal subarachnoid hemorrhage (SAH) to determine the appropriateness of this performance metric and to identify potential avenues for improved patient care.

METHODS

The authors retrospectively reviewed the medical records of all patients who received surgical or endovascular treatment for aneurysmal SAH at Barnes-Jewish Hospital between 2003 and 2013. Two senior faculty identified by consensus the primary medical/surgical diagnosis associated with readmission as well as the underlying causes of rehospitalization.

RESULTS

Among 778 patients treated for aneurysmal SAH, 89 experienced a total of 97 readmission events, yielding a readmission rate of 11.4%. The median time from discharge to readmission was 9 days (interquartile range 3-17.5 days). Actual hydrocephalus or potential concern for hydrocephalus (e.g., headache) was the most frequent diagnosis (26/97, 26.8%), followed by infections (e.g., wound infection [5/97, 5.2%], urinary tract infection [3/97, 3.1%], and pneumonia [3/97, 3.1%]) and thromboembolic events (8/97, 8.2%). In most cases (75/97, 77.3%), we did not identify any treatment lapses contributing to readmission. The most common underlying causes for readmission were unavoidable development of SAH-related pathology (e.g., hydrocephalus; 36/97, 37.1%) and complications related to neurological impairment and immobility (e.g., thromboembolic event despite high-dose chemoprophylaxis; 21/97, 21.6%). The authors determined that 22/97 (22.7%) of the readmissions were likely preventable with alternative management. In these cases, insufficient outpatient medical care (for example, for hyponatremia; 16/97, 16.5%) was the most common shortcoming.

CONCLUSIONS

Most readmissions after aneurysmal SAH relate to late consequences of hemorrhage, such as hydrocephalus, or medical complications secondary to severe neurological injury. Although a minority of readmissions may potentially be avoided with closer medical follow-up in the transitional care environment, readmission after SAH is an insensitive and likely inappropriate hospital performance metric.

Risk Factors Associated With 30-day Readmissions After Instrumented Spine Surgery in 14,939 Patients: 30-day readmissions after instrumented spine surgery

STUDY DESIGN

A retrospective review of instrumented spine registry from an integrated US healthcare system.

OBJECTIVE

Investigate the 30-day readmission rate and risk factors after instrumented spine surgery.

SUMMARY OF BACKGROUND DATA

Published readmission rates range from 2% to over 20%. We were interested in learning which patients were at greatest risk, when did readmissions occur, and why.

METHOD

30-day readmission rates were determined for 14,939 patients after an index spine procedure between 1/2009 and 3/2013. Data were analyzed with descriptive statistics, univariate, and multivariate logistic regression analysis.

RESULT

The average age of the cohort was 59 (SD = 13.4) and 52% were female. The 30-day readmission rate was 5.5% (821/14,939). The temporal pattern for readmission was: 17% (140) at week 1, 48% (394) at week 2, 72% (591) at week 3, and 100% (821) at week 4. The leading causes were wound complications (infection, hematoma, dehiscence, seroma), sepsis, pain management, pneumonia, and pulmonary emboli/deep venous thrombosis. In a multivariate model, readmission risk factors were: malignancy (OR 2.99, 95% CI: 1.56, 5.73), operative time more than 400 minutes (OR 2.59, 95% CI: 1.66, 4.02), operative time 300-399 minutes (OR 2.33, 95% CI: 1.54-3.52), hospital stay 6-10 days (OR 2.03, 95% CI: 1.31-3.14), hospital stay more than 10 days (OR 1.85, 95% CI: 1.1, -3.08), surgical complications (OR 1.67, 95% CI: 1.18, 2.36), operative time 200-299 (OR 1.52, 95% CI: 1.04, 2.22), depression (OR 1.48, 95% CI: 1.14, 1.93), rheumatoid arthritis (OR 1.45, 95% CI: 1.05, 2.01), deficiency anemia (OR 1.30, 95% CI: 1.05, 1.61), and hypothyroidism (OR 1.29, 95% CI: 1.01, 1.64).

CONCLUSION

Surgical complications (dural tear, deep infections, superficial infections, epidural hematoma), malignancy, lengthy operative times, and lengthy initial hospitalizations are all risk factors for 30-day readmission. These findings should be considered during preoperative assessment and surgical planning.

LEVEL OF EVIDENCE

3.

Thirty-day readmission rates in orthopedics: a systematic review and meta-analysis

Background

Hospital readmission rates are being used to evaluate performance. A survey of the present rates is needed before policies can be developed to decrease incidence of readmission. We address three questions: What is the present rate of 30-day readmission in orthopedics? How do factors such as orthopedic specialty, data source, patient insurance, and time of data collection affect the 30-day readmission rate? What are the causes and risk factors for 30-day readmissions?

Methods/Findings

A review was first registered with Prospero (CRD42014010293, 6/17/2014) and a meta-analysis was performed to assess the current 30-day readmission rate in orthopedics. Studies published after 2006 were retrieved, and 24 studies met the inclusion criteria. The 30-day readmission rate was extrapolated from each study along with the orthopedic subspecialty, data source, patient insurance, time of collection, patient demographics, and cause of readmission. A sensitivity analysis was completed on the stratified groups. The overall 30-day readmission rate across all orthopedics was 5.4 percent (95% confidence interval: 4.8,6.0). There was no significant difference between subspecialties. Studies that retrieved data from a multicenter registry had a lower 30-day readmission rate than those reporting data from a single hospital or a large national database. Patient populations that only included Medicare patients had a higher 30-day readmission rate than populations of all insurance. The 30-day readmission rate has decreased in the past ten years. Age, length of stay, discharge to skilled nursing facility, increased BMI, ASA score greater than 3, and Medicare/Medicaid insurance showed statistically positive correlation with increased 30-day readmissions in greater than 75 percent of studies. Surgical site complications accounted for 46 percent of 30-day readmissions.

Conclusions

This meta-analysis shows the present rate of 30-day readmissions in orthopedics. Demonstrable heterogeneity between studies underlines the importance of uniform collection and reporting of readmission rates for hospital evaluation and reimbursement.

Cranial neurosurgical 30-day readmissions by clinical indication

OBJECT

Postsurgical readmissions are common and vary by procedure. They are significant drivers of increased expenditures in the health care system. Reducing readmissions is a national priority that has summoned significant effort and resources. Before the impact of quality improvement efforts can be measured, baseline procedure-related 30-day all-cause readmission rates are needed. The objects of this study were to determine population-level, 30-day, all-cause readmission rates for cranial neurosurgery and identify factors associated with readmission.

METHODS

The authors identified patient discharge records for cranial neurosurgery and their 30-day all-cause readmissions using the Agency for Healthcare Research and Quality (AHRQ) State Inpatient Databases for California, Florida, and New York. Patients were categorized into 4 groups representing procedure indication based on ICD-9-CM diagnosis codes. Logistic regression models were developed to identify patient characteristics associated with readmissions. The main outcome measure was unplanned inpatient admission within 30 days of discharge.

RESULTS

A total of 43,356 patients underwent cranial neurosurgery for neoplasm (44.23%), seizure (2.80%), vascular conditions (26.04%), and trauma (26.93%). Inpatient mortality was highest for vascular admissions (19.30%) and lowest for neoplasm admissions (1.87%; p < 0.001). Thirty-day readmissions were 17.27% for the neoplasm group, 13.89% for the seizure group, 23.89% for the vascular group, and 19.82% for the trauma group (p < 0.001). Significant predictors of 30-day readmission for neoplasm were Medicaid payer (OR 1.33, 95% CI 1.15-1.54) and fluid/electrolyte disorder (OR 1.44, 95% CI 1.29-1.62); for seizure, male sex (OR 1.74, 95% CI 1.17-2.60) and index admission through the emergency department (OR 2.22, 95% CI 1.45-3.43); for vascular, Medicare payer (OR 1.21, 95% CI 1.05-1.39) and renal failure (OR 1.52, 95% CI 1.29-1.80); and for trauma, congestive heart failure (OR 1.44, 95% CI 1.16-1.80) and coagulopathy (OR 1.51, 95% CI 1.25-1.84). Many readmissions had primary diagnoses identified by the AHRQ as potentially preventable.

CONCLUSIONS

The frequency of 30-day readmission rates for patients undergoing cranial neurosurgery varied by diagnosis between 14% and 24%. Important patient characteristics and comorbidities that were associated with an increased readmission risk were identified. Some hospital-level characteristics appeared to be associated with a decreased readmission risk. These baseline readmission rates can be used to inform future efforts in quality improvement and readmission reduction.

Cost-effectiveness of lumbar discectomy and single-level fusion for spondylolisthesis: experience with the NeuroPoint-SD registry

OBJECT

There is significant practice variation and uncertainty as to the value of surgical treatments for lumbar spine disorders. The authors' aim was to establish a multicenter registry to assess the efficacy and costs of common lumbar spinal procedures by using prospectively collected outcomes.

METHODS

An observational prospective cohort study was completed at 13 academic and community sites. Patients undergoing single-level fusion for spondylolisthesis or single-level lumbar discectomy were included. The 36-Item Short Form Health Survey (SF-36) and Oswestry Disability Index (ODI) data were obtained preoperatively and at 1, 3, 6, and 12 months postoperatively. Power analysis estimated a sample size of 160 patients: lumbar disc (125 patients) and lumbar listhesis (35 patients). The quality-adjusted life year (QALY) data were calculated using 6-dimension utility index scores. Direct costs and complication costs were estimated using Medicare reimbursement values from 2011, and indirect costs were estimated using the human capital approach with the 2011 US national wage index. Total costs equaled $14,980 for lumbar discectomy and $43,852 for surgery for lumbar spondylolisthesis.

RESULTS

There were 198 patients enrolled over 1 year. The mean age was 46 years (49% female) for lumbar discectomy (n = 148) and 58.1 years (60% female) for lumbar spondylolisthesis (n = 50). Ten patients with disc herniation (6.8%) and 1 with listhesis (2%) required repeat operation at 1 year. The overall 1-year follow-up rate was 88%. At 30 days, both lumbar discectomy and single-level fusion procedures were associated with significant improvements in ODI, visual analog scale, and SF-36 scores (p = 0.0002), which persisted at the 1-year evaluation (p < 0.0001). By 1 year, more than 80% of patients in each cohort who were working preoperatively had returned to work. Lumbar discectomy was associated with a gain of 0.225 QALYs over the 1-year study period ($66,578/QALY gained). Lumbar spinal fusion for Grade I listhesis was associated with a gain of 0.195 QALYs over the 1-year study period ($224,420/QALY gained).

CONCLUSIONS

This national spine registry demonstrated successful collection of high-quality outcomes data for spinal procedures in actual practice. These data are useful for demonstrating return to work and cost-effectiveness following surgical treatment of single-level lumbar disc herniation or spondylolisthesis. One-year cost per QALY was obtained, and this cost per QALY is expected to improve further by 2 years. This work sets the stage for real-world analysis of the value of health interventions.

Predictors of readmission in orthopaedic trauma surgery

OBJECTIVES

This study of patients who had operative treatment of skeletal trauma addresses (1) the association between readmission within 30 days of discharge and comorbidities and (2) differences in factors associated with all-cause readmissions and those because of a surgical adverse event.

DESIGN

Retrospective study.

SETTING

Tertiary care referral center.

PATIENTS

Three thousand four hundred fifty-two operations for skeletal trauma between 2008 and 2012 with comorbidities quantified using the updated Charlson comorbidity index (CCI).

OUTCOME MEASUREMENT

Readmission to the hospital within 30 days of surgery and the subset of readmissions because of adverse events related directly to surgery.

RESULTS

There was a significant association between readmission within 30 days of surgery and higher CCI (P < 0.001), older age (P < 0.001), and marital status (widowed) (P < 0.001). The factors associated with readmission related to an adverse event were identical. The best multivariable logistic regression models for all-cause 30-day readmission and 30-day readmission related to a surgical adverse event included CCI and older age in both models (odds ratio 1.1, P < 0.01, pseudo R = 0.03).

CONCLUSIONS

Older patients and patients with greater comorbidity are more likely to be readmitted within 30 days of surgery for musculoskeletal trauma, whether for a surgical adverse event or another reason. The best multivariable models predicted very little of the variability in readmission, which reflects the complexity of readmission and the difficulty reducing the risk to a few specific factors.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Short-term adverse events, length of stay, and readmission after iliac crest bone graft for spinal fusion

STUDY DESIGN

Retrospective cohort study of 13,927 patients, 820 of whom received iliac crest bone graft (ICBG).

OBJECTIVE

To compare adverse events, length of stay (LOS), and readmission for patients receiving ICBG with those who did not using multivariate analysis to control for potentially confounding factors.

SUMMARY OF BACKGROUND DATA

The use of ICBG in spinal fusion has been associated with increased surgical time, LOS, and donor site morbidity. Development of expensive bone graft substitutes has been predicated on these issues. Data on the effect of bone graft harvest on LOS and readmission rate are sparse, and multivariate analysis has not been used to control for confounding factors.

METHODS

Prospectively collected data from the American College of Surgeons National Surgical Quality Improvement Project 2010-2012 database were retrospectively reviewed. This includes demographics, comorbidities, surgical data, and hospital and 30-day follow-up outcomes data including adverse events, LOS, and readmission.

RESULTS

Only 5.9% of spinal fusions use ICBG. Bivariate logistic regression (used for categorical variables) found the ICBG cohort was more likely to have a postoperative blood transfusion (11.6% vs. 5.5%, P < 0.001). Bivariate linear regression (used for continuous variables) found the ICBG cohort to have an extended operative time (+36.0 min, P < 0.001) and extended LOS (+0.6 d, P < 0.001).Multivariate analyses controlling for comorbidities, demographics, and approach-determined postoperative blood transfusion (odds ratio, 1.5), extended operative time (+22.0 min, P < 0.001), and LOS (+0.2 d, P = 0.037) to be significantly associated with ICBG use.No other adverse event was significantly associated with ICBG use. Readmission rates were not significantly different.

CONCLUSION

This study used a large national database cohort and identified increased postoperative blood transfusion, extended operative time, and increased LOS as short-term outcomes associated with ICBG on multivariate analysis. Other short-term morbidities were not significantly associated with ICBG. Readmission rates were not affected.

LEVEL OF EVIDENCE

4.

Thirty-day readmission following total hip and knee arthroplasty - a preliminary single institution predictive model

We sought to identify demographic or care process variables associated with increased 30-day readmission within the total hip and knee arthroplasty patient population. Using this information, we generated a model to predict 30-day readmission risk following total hip and knee arthroplasty procedures. Longer index length of stay, discharge disposition to a nursing facility, blood transfusion, general anesthesia, anemia, anticoagulation status prior to index admission, and Charlson Comorbidity Index greater than 2 were identified as independent risk factors for readmission. Care process factors during the hospital stay appear to have a large predictive value for 30-day readmission. Specific comorbidities and patient demographic factors showed less significance. The predictive nomogram constructed for primary total joint readmission had a bootstrap-corrected concordance statistic of 0.76.

Predictors of unplanned readmission in patients undergoing lumbar decompression: multi-institutional analysis of 7016 patients

Object

Unplanned hospital readmission represents a large financial burden on the Centers for Medicare and Medicaid Services, commercial insurance payers, hospitals, and individual patients, and is a principal target for cost reduction. A large-scale, multi-institutional study that evaluates risk factors for readmission has not been previously performed in patients undergoing lumbar decompression procedures. The goal of this multicenter retrospective study was to find preoperative, intraoperative, and postoperative predictive factors that result in unplanned readmission (UR) after lumbar decompression surgery.

Methods

The National Surgical Quality Improvement Program (NSQIP) database was retrospectively reviewed to identify all patients who received lumbar decompression procedures in 2011. Risk-adjusted multivariate logistic regression analysis was performed to estimate independent predictors of UR.

Results

The overall rate of UR among patients undergoing lumbar decompression was 4.4%. After multivariate logistic regression analysis, anemia (odds ratio [OR] 1.48), dependent functional status (OR 3.03), total operative duration (OR 1.003), and American Society of Anesthesiologists Physical Status Class 4 (OR 3.61) remained as independent predictors of UR. Postoperative complications that were significantly associated with UR included overall complications (OR 5.18), pulmonary embolism (OR 3.72), and unplanned reoperation (OR 56.91).

Conclusions

There were several risk factors for UR after lumbar spine decompression surgery. Identification of high-risk patients and appropriate allocation of resources to reduce postoperative incidence may reduce the readmission rate.

Analysis of 30-day readmissions among neurosurgical patients: surgical complication avoidance as key to quality improvement

OBJECT.: In terms of measuring quality of care and hospital performance, an outcome of increasing interest is the 30-day readmission rate. Recent health care policy making has highlighted the necessity of understanding the factors that influence readmission. To elucidate the rate, reason, and predictors of readmissions at a tertiary/quaternary neurosurgical service, the authors studied 30-day readmissions for the Department of Neurosurgery at two University of California, Los Angeles (UCLA), hospitals.

METHODS

Over a 3-year period, the authors retrospectively identified adult and pediatric patients who had been discharged from the UCLA Medical Center after having undergone a major neurosurgical procedure and being readmitted within 30 days. Data were obtained on demographics, follow-up findings, diagnosis and reason for readmission, major operations performed, and length of stay during index admission and readmission. Reasons for readmission were broadly categorized into surgical, medical diagnosis/complication, problem associated with the original diagnosis, neurological decompensation, pain management, and miscellaneous. For further characterization, subgroup analysis and in-depth chart review were performed.

RESULTS

Over the study period, 365 (6.9%) of 5569 patients were readmitted within 30 days. The most common diagnosis at index admission was brain tumor (102 patients), followed by CSF shunt malfunction (63 patients). The most common reason for readmission was surgical complication (50.1%). Among those with surgical complications, the largest subgroup consisted of patients with CSF shunt-related problems (77 patients). The second and third largest subgroups were surgical site infection and CSF leakage (41 and 31 patients, respectively). Medical diagnosis/complication was the second most frequent (27.9%) reason for readmission.

CONCLUSIONS

Surgical complications seem to be a major reason for readmission at the neurosurgical practice studied. Results indicate that the outcomes that are amenable to and would have the greatest effect on quality improvement are CSF shunt-related complications, surgical site infections, and CSF leaks.

Return to system within 30 days of discharge following pediatric shunt surgery

OBJECT

The rate of readmission after CSF shunt surgery is significant and has caught the attention of purchasers of health care. However, a detailed description of clinical scenarios that lead to readmissions and reoperations after index shunt surgery is lacking in the medical literature.

METHODS

This study included 1755 shunt revision and insertion surgeries that were performed at a single institution between May 1, 2009, and April 30, 2013. Demographic, socioeconomic, and clinical characteristics were prospectively collected in the administrative, business, and operating room databases. Clinical events within the 30 days following discharge were reviewed and analyzed. Two events of interest, Emergency Department (ED) utilization and reoperation, were further analyzed for risk factor associations by using multivariate logistic regression.

RESULTS

There were 290 readmissions within 30 days of discharge (16.5%). Admission sources included ED (n = 216), hospital transfers (n = 23), and others. Of the 290 readmissions, 184 were associated with an operation, but only 165 of these were performed by the neurosurgical service. These included surgeries for shunt occlusion and externalization (n = 150), wound revision (n = 7), and other neurosurgical procedures that were not shunt related (n = 8). The remaining readmissions (n = 106) were not associated with an operation, and only 59 patients were admitted for issues related to the index shunt surgery. When return to the ED was the dependent variable in a multivariate regression model, patients who returned to the ED were more likely to be from the Atlanta metropolitan area and to be either uninsured or insured with public assistance. When reoperation was the dependent variable, patients whose surgery started after 3 p.m. were more likely to undergo subsequent CSF shunt revision surgery on readmission.

CONCLUSIONS

Of the readmissions within 30 days of shunt surgery, 74.5% were related to the index shunt surgery. Whether and to what extent these readmissions are preventable continues to be controversial. Further study is needed to identify modifiable risk factors that may eventually improve patient care.

Return to system within 30 days of pediatric neurosurgery

OBJECT

Quality assessment measures have not been well developed for pediatric neurosurgical patients. This report documents the authors' experience in extracting information from an administrative database to establish the rate of return to system within 30 days of pediatric neurosurgical procedures.

METHODS

Demographic, socioeconomic, and clinical characteristics were prospectively collected in administrative, business, and operating room databases. The primary end point was an unexpected return to the hospital system within 30 days from the date of a pediatric neurosurgical procedure. Statistical methods were used to identify clinical and demographic factors associated with the primary end point.

RESULTS

There were 1358 pediatric neurosurgical procedures performed in the Children's Healthcare of Atlanta operating rooms in 2012, with 37.4% of these surgeries being preceded by admissions through the emergency department. Medicare or Medicaid was the payor for 54.9% of surgeries, and 37.6% of surgeries were shunt related. There were 148 unexpected returns to the system within 30 days after surgery, and in 109 of these cases, the patient had a presenting complaint that was attributable to the index surgery (related returns). The most common complaints were headache, nausea, vomiting, or seizure after shunt revision or cranial procedures (n = 62). The next most common reason for re-presentation was for wound concerns (n = 30). Thirty-seven of the 109 related returns resulted in a reoperation. The monthly rate of related returns was 8.1% ± 2.5% over the 12-month study period. When using related returns as the dependent variable, the authors found that patients who underwent a shunt-related surgery were both more likely to unexpectedly return to the system (OR 1.86, p = 0.008) and to require surgery upon readmission (OR 3.28, p = 0.004). Because an extended hospitalization shortened the window of time for readmission after surgery, extended length of stay was protective against return to system within 30 days of surgery. Importantly, if related and unrelated returns were analyzed together as the dependent variable (n = 148), no independent clinical and demographic risk factor could be identified.

CONCLUSIONS

Quality assessment measures need to be clearly and carefully defined, as the definition itself will impact the analytical results. Clinicians must play a leading role in the development of these measures to ensure their clinical meaningfulness.

Does 30-Day Readmission Affect Long-term Outcome Among Glioblastoma Patients?

BACKGROUND:

Research on readmissions has focused mainly on the economic and resource burden it places on hospitals.

OBJECTIVE:

To evaluate the effect of 30-day readmission on overall survival among newly diagnosed glioblastoma multiforme (GBM) patients.

METHODS:

A nationwide cohort of GBM patients diagnosed between 1991 and 2007 was studied using the Surveillance, Epidemiology and End Results Medicare database. Multivariate models were used to determine factors associated with readmission and overall survival. Odds ratio, hazard ratio, 95% confidence interval, and P values were reported. Complete case and multiple imputation analyses were performed.

RESULTS:

Among the 2774 newly diagnosed GBM patients undergoing surgery at 442 hospitals nationwide, 437 (15.8%) were readmitted within 30 days of the index hospitalization. Although 63% of readmitted patients returned to the index hospital where surgery was performed, a significant portion (37%) were readmitted to nonindex hospitals. The median overall survival for readmitted patients (6.0 months) was significantly shorter than for nonreadmitted (7.6 months; P &lt; .001). In a confounder-adjusted imputed model, 30-day readmission increased the hazard of mortality by 30% (hazard ratio, 1.3; P &lt; .001). Neurological symptoms (30.2%), thromboembolic complications (19.7%), and infections (17.6%) were the leading reasons for readmission.

CONCLUSION:

Prior studies that have reported only the readmissions back to index hospitals are likely underestimating the true 30-day readmission rate. GBM patients who were readmitted within 30 days had significantly shorter survival than nonreadmitted patients. Future studies that attempt to decrease readmissions and evaluate the impact of reducing readmissions on patient outcomes are needed.

Patient-based and surgical characteristics associated with the acute development of deep venous thrombosis and pulmonary embolism after spine surgery

STUDY DESIGN

Retrospective analysis of a prospectively collected data set.

OBJECTIVE

Identify the incidence of, and risk factors for, deep venous thrombosis (DVT) and pulmonary embolism (PE) after spine surgery.

SUMMARY OF BACKGROUND DATA

Determination of ideal candidates for chemoprophylaxis after spine surgery is limited by the state of the literature, including incomplete understanding regarding the incidence of DVT and PE, as well as an inability to quantify specific risk factors among patients.

METHODS

The 2005 to 2011 data set of the National Surgical Quality Improvement Program was queried to identify all individuals having undergone spine surgery. Demographic data, medical comorbidities, surgical characteristics, and the presence of DVT, PE, and/or mortality were abstracted for all individuals meeting inclusion criteria. Unadjusted univariate analysis was performed to identify variables that were potentially associated with the development of DVT or PE after surgery. A multivariate logistic regression test, controlling for other factors present in the model, was subsequently performed. Predictor variables that maintained significance after multivariate testing were considered influential in the development of DVT and/or PE.

RESULTS

There were 27,730 patients who received spine procedures in this cohort. The average age was 56.4 (± 15.1) years. Lumbar spine procedures made up 61% of interventions. Death occurred in 87 instances (0.3%). The venous thromboembolic rate was 1%, with 206 individuals (0.7%) sustaining DVT and 113 (0.4%) developing a PE. Body mass index 40 and greater, age 80 years and older, operative time exceeding 261 minutes, and American Society of Anesthesiologists classification 3 or higher were identified as significant independent predictors of DVT, whereas body mass index 40 and greater, operative time exceeding 261 minutes, and male sex were associated with the development of PE.

CONCLUSION

Multiple independent risk factors for the development of DVT and/or PE after spine surgery were identified. Patients with these characteristics may require additional counseling, procedural modification, or prophylaxis against venous thromboembolic events.