Lumbar Drainage May Represent A Cost Saving Method for Skull Base Surgeries

Background Cerebrospinal fluid leak (CSF) is a common complication after endoscopic endonasal surgery (EES) of the skull base. Our group recently presented a randomized control trial demonstrating the utility of perioperative lumbar drainage (LD) in reducing CSF leak rate; here, we present a secondary analysis of the RCT to evaluate secondary measures of cost associated with perioperative LD usage in the reduction of CSF leak rate.

Methods Patients undergoing EES with dural resection and standard reconstruction were randomized at the completion of surgery to either postoperative LD at 10 mL/hour for 72 hours or a control group. Inclusion criteria were entry into the anterior or posterior fossa and dural defect >1 cm², or arachnoid dissection, or entry into an arachnoid cistern or ventricle. Primary outcomes included 30-day hospital length of stay (LOS), ICU LOS, rate of meningitis, pneumocephalus, hydrocephalus, and pulmonary embolus/deep venous thrombosis (PE/DVT). Secondary outcomes included assessing differences in Medicaid reimbursement through DRG groupings with major, minor, or no complications.

Results A total of 125 patients were included in the secondary analysis. Age (p = 0.33), BMI (p = 0.28), and gender (p = 0.21) did not vary between arms. The treatment arm had an overall 8.3% CSF leak rate compared with 20.99% in the control group (p = 0.013).

Mean 30-day LOS was 7.02 days in the treatment arm and did not significantly vary from the average of 6.16 days in the control arm (p = 0.351). ICU LOS did not differ between the treatment arm and the control arm (2.27 vs. 1.85, respectively, p = 0.19). Overall rate of readmission, meningitis, pneumocephalus, hydrocephalus, and PE/DVT did not vary between treatment arms (p = 0.96, 0.21, 0.28, 0.16, and 0.26, respectively). Additionally, a catch-all “other” complication rate did not significantly vary between treatment and control arms (p = 0.98). However, patients with CSF leaks experienced longer 30-day LOS (11.50 vs. 6.99, p < 0.001) and 21.99 times higher odds of readmission (95% CI: 6.78–71.36).

Medicaid reimbursement did not significantly differ between treatment arms and averaged $23,574.32 per patient in the treatment arm and $25,154.05 per patient in the control arm.

Conclusion Among patients undergoing EES in the anterior and posterior fossa, perioperative LD significantly lowers the rate of postoperative CSF leak. There is no evidence of increased secondary measures of cost including increased rates of meningitis, pneumocephalus, hydrocephalus, and PE/DVT, which have been previously reported or theorized. LD shows equivalent Medicaid reimbursement while decreasing CSF leak rate with potential decreases in LOS and hospital readmissions through this reduction. We believe that LD may decrease hospital cost while maintaining equivalent reimbursement.