Introduction: Decompressive craniectomy is a reliable lifesaving maneuver. Obtaining a culture swab of the bone flap at the time of decompression with the premise that culture-positive autologous bone flaps (+ABF) should be discarded in favor of synthetic flaps (SF) at the time of subsequent cranioplasty is controversial. Recently we started re-implanting ABF+ flaps when the cultures returned with presumed contaminate (Propionibacterium acnes, Coagulase-negative Staphylococcus aureus, etc).
Methods: We retrospectively reviewed cranioplasty operations performed at our institution over the past 10 years including the initial bone flap culture.
Results: From 2004 to 2014 there were 754 cranioplasties performed. Initial indication for decompression included trauma (51.5%), spontaneous IPH (13.8%), aneurysmal subarachnoid hemorrhage (13.5%), malignant infarction (9.7%), and other (11.5%). Sixty percent were male. Average follow up was 533 days.
Median date of cranioplasty after original decompression was 123 days (range 2-9,855 days). Sterile ABF was used 65.6% of cases, a synthetic graft in 29.4%, and +ABF in 5%. Overall, the rate of infection requiring removal was 6.6% occurring at an average of 190 days and median of 31 day post-operatively (range 8-2,035 days).
The rates of infection were comparable between sterile ABF (7%), +ABF (8%) grafts, and SF (5.5%) (p=0.34). Cranioplasty occurring = 14days after decompression was a significant predictor of infection (p=0.03). Neither age, gender, indication for craniectomy, or place of discharge predicted infection.
Synthetic cranioplasty was placed for the sole indication of +ABF in 89 cases (40% of all synthetic cases). The cost of these flaps was over $500,000.
Conclusions: Ultra-early Cranioplasty (=14 days) is a significant risk factor for post-operative infection requiring explantation. Additionally, replacing +AFB with SF at the time of cranioplasty does not reduce the risk of subsequent infection but does add a substantial increase in cost.
Patient Care: By adjusting existent protocols for swabbing all autologous bone flaps at the time of decompression, hospitals can decrease costs associated with patient care. Additionally, with identification of modifiable risk factors for infection, practices can be altered in an effort to further reduce costs and morbidity associated with patient care.
Learning Objectives: 1) To review the rates of complication with cranioplasty 2) to evaluate whether swabbing bone flaps has a role in reducing the rate of infection, 3) to determine if there are any identifiable risk factors for developing infection. 4) To identify the costs associated with screening bone flaps for bacterial infections