Risk Factors for Graft Infection After Cranioplasty in Patients with Large Hemicranial Bony Defects

To identify infection incidence and related risk factors in patients who underwent cranioplasty (CP) after unilateral decompressive craniectomy (DC).

CP after DC was performed in 45 patients from April 2011 through January 2012. The covariates studied were compared with occurrence versus nonoccurrence of infection. Univariate analysis was performed, followed by a multivariate analysis and development of independent logistic regression models with significance of 5%.

Wound infections were observed in 24% of cases. Patients treated with polymethyl methacrylate flaps had a 31% rate of infection compared with 12% in patients treated with autologous flaps, but the difference was not statistically significant (P = 0.279). Increased risk of infection was associated with performing CP during the same period of hospitalization as DC (45% vs. 8%; P = 0.006), recent systemic infection (53% vs. 10%; P = 0.003), a Glasgow Outcome Scale score lower than 4 (48% vs. none; P < 0.001), motor deficit (42% vs. 5%; P = 0.011), and lower levels of hemoglobin (P < 0.001). Another risk factor for infection was an interval between DC and CP of 29-84 days compared with >168 days (P = 0.007).

The incidence of wound infection was high. Risk factors included motor deficits, Glasgow Outcome Scale score <4, lower hemoglobin levels, recent systemic infections, interval between DC and CP of 29-84 days, and DC and CP performed during the same hospitalization. Performing CP during a different hospitalization may reduce the risk of graft infection because the hemoglobin level would be higher, and patients would be less dependent and free of recent infection.