The Changes of Retropharyngeal Space and Retrotracheal Space in Patients Undergoing Anterior Cervical Discectomy and Fusion Surgery: A Retrospective Study

Aims: Upper airway complications after anterior cervical discectomy and fusion (ACDF) surgery are potentially life threatening. The causes of postoperative airway swelling are tissue swelling in the pharynx in most cases and haematoma in some cases. This study was conducted to identify the postoperative time course of the prevertebral soft tissue swelling after ACDF and compare it between multi-level and single-level surgeries.

Study Design: Case series study.

Place and Duration of the Study: Department of Anesthesia, Nagasaki Rosai Hospital, Sasebo, Japan; 17 months.

Methodology: We examined 28 consecutive patients who underwent multi-level ACDF surgery and 23 consecutive patients who underwent single-level ACD surgery for degenerative disease and traumatic injury, retrospectively from May 2012 to September 2014. The lateral radiograph of the cervical spine was taken preoperatively, immediately after surgery, on the first postoperative day (1POD), and a few days after surgery (2/3POD). The anteroposterior thickness of the prevertebral soft tissue was measured at the third cervical vertebral level (retropharyngeal space) and the sixth cervical vertebral level (retrotracheal space) on the radiograph. We compared the thickness at predetermined time points between the 2 groups.

Results: Both retropharyngeal and retrotracheal spaces increased immediately after the operation compared with the preoperative values in both groups. Moreover, the retropharyngeal space at 1POD significantly increased, compared with the preoperative values and immediately after the operation in both groups. The retrotracheal space at 1POD increased, compared with immediately after the operation in single--level surgeries, but not in multi-level surgeries. There are no significant differences in both spaces between the 2 groups at any time point.

Conclusions: Regardless of the surgical level, attention to upper airway swelling and complications after anterior cervical discectomy and fusion surgery is needed during the postoperative period as well as immediately after the operation.