Excess cost and inpatient stay of treating deep spinal surgical site infections

To determine the excess cost and hospitalisation associated with surgical site infections (SSI) following spinal operations in a New Zealand setting.

We identified inpatients treated for deep SSI following primary or revision spinal surgery at a regional tertiary spinal centre between 2009 and 2016. Excess cost and excess length of stay (LOS) were calculated via a clinical costing system using procedure-matched controls.

Twenty-eight patients were identified. Twenty-five had metalware following spinal fusion surgery, while three had non-instrumented decompression and/or discectomy. Five were diagnosed during their index hospitalisation and 23 (82%) were re-admitted. The average excess SSI cost was NZ$51,434 (range $1,398-$262,206.16) and LOS 37.1 days (range 7-275 days). Infections following metalware procedures had a greater excess cost (average $56,258.90 vs. $11,228.61) and LOS (average 40.4 days vs. 9.7 days) than procedures without metalware.

The costs associated with spinal SSI are significant and comparable to a previous New Zealand study of hip and knee prosthesis SSI. More awareness of the high costs involved should encourage research and implementation of infection prevention strategies.