Patient characteristics associated with increased postoperative length of stay and readmission after elective laminectomy for lumbar spinal stenosis

Abstract

Study design: Retrospective cohort.

Objective: To identify factors that were independently associated with increased postoperative length of stay (LOS) and readmission in patients who underwent elective laminectomy for lumbar spinal stenosis.

Summary of background data: Lumbar spinal stenosis is a common pathology that is traditionally treated with decompressive laminectomy. Risk factors associated with increased LOS and readmission have not been fully characterized for laminectomy.

Methods: Patients who underwent laminectomy for lumbar spinal stenosis during 2011 and 2012 were identified from the American College of Surgeons National Surgical Quality Improvement Program database. Patient characteristics were tested for association with LOS and readmission using bivariate and multivariate analyses. Patients with LOS more than 10 days were excluded from the readmission analysis as the American College of Surgeons National Surgical Quality Improvement Program only captures readmissions within 30 postoperative days, and the window for potential readmission was deemed too short for patients staying longer than 10 days.

Results: A total of 2358 patients who underwent laminectomy met inclusion criteria. The average age was 66.4 ± 11.7 years (mean ± standard deviation). Average postoperative LOS was 2.1 ± 2.6 days. Of those meeting criteria for readmission analysis, 3.7% of patients (86 of 2339) were readmitted within 30 days postoperatively.Independent risk factors for prolonged LOS were increased age (P < 0.001), increased body mass index (P = 0.004), American Society of Anesthesiologists class 3-4 (P = 0.005), and preoperative hematocrit less than 36.0 (P = 0.001). Independent risk factors for readmission were increased age (P = 0.013), increased body mass index (P = 0.040), American Society of Anesthesiologists class 3-4 (P < 0.001), and steroid use (P = 0.001). The most common reason for readmission was surgical site-related infections (25.0% of patients readmitted in 2012).

Conclusion: The identified factors associated with LOS and readmission after lumbar laminectomy may be useful for optimizing patient care.

Figure 1

Postoperative length of stay (LOS) after laminectomy for lumbar spinal stenosis. Readmitted patients and non-readmitted patients are differentiated. Only cases with LOS less than or equal to the 99^th percentile LOS (10 days) were included in the readmission analysis (cases to the right of the dashed line were excluded).