Cranial neurosurgical 30-day readmissions by clinical indication

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.

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.

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.

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.