Potential Risk Factors for Perioperative Complications After Cervical Spine Surgery in Patients With RA

A small study revealed several characteristics, including short height, that could be risk factors for perioperative complications among patients with rheumatoid arthritis (RA) undergoing cervical spine surgery.

According to the retrospective study published in Arthritis Research & Therapy, perioperative complications were significantly associated with low height, high American Society of Anesthesiologists Physical Status (ASA-PS), high-dose prednisolone use, and progression of cervical spine lesions in early disease stages of RA.

“Rheumatoid arthritis (RA) often causes cervical spine lesions as the disease condition progresses, which induce occipital neuralgia or cervical myelopathy requiring surgical interventions,” the study authors explained. “Meanwhile, patients with RA are susceptible to infection or other complications in the perioperative period because they frequently have comorbidities and use immunosuppressive medications.”

Because risk factors for perioperative complications after cervical spine surgery were not yet known, researchers conducted a retrospective study that included 139 patients with RA who underwent primary cervical spine surgery between January 2001 and March 2020 at the National Hospital Organization Kyushu Medical Center in Japan. Cervical spine lesions were categorized as atlantoaxial subluxation (AAS), vertical subluxation (VS), and subaxial subluxation (SAS).

Data was collected via medical records, and baseline characteristics and surgery-related factors were used to compare characteristics of patients who did and did not have complications after surgery. Comorbidities at the time of surgery that could potentially affect the occurrence of complications were evaluated using the Charlson comorbidity index (CCI).

The authors found that 28 (20.1%) patients experienced perioperative complications, and third of complications (10) were defined as severe.

The following significant associations were made in univariate analyses:

• Lower height (odds ratio [OR]: 0.928, P = .007)
• Higher ASA‐PS (OR: 2.296, P = .048)
• Longer operation time (OR: 1.013, P = .003)
• More bleeding volume (OR: 1.004, P = .04)
• Higher rates of VS (OR: 2.914, P = .015)
• Higher rates of SAS (OR: 2.507, P = .036)
• Occipito‐cervical (OC) fusion (OR: 3.438, P = .023)
• OC/thoracic (long) fusion (OR: 8.021, P = .002)

Because RA-associated cervical spine lesions and selected procedure have been shown to be confounding factors to each other, the authors made 2 multivariate analysis models, with one relating to cervical spine lesions and another for surgical procedures. They also conducted stepwise regression analyses to identify variables that univariate analysis indicated were significant risk factors.

Multivariate analyses found that lower height, higher ASA-PS, and long fusion remained risk factors for complications. Meanwhile, OC fusion, long fusion, high‐dose prednisolone use, and higher rates of SAS—as well as operative procedures for SAS—were all associated with severe complications.

While the study suggested mean ASA-PS value was significantly higher in patients who experience perioperative complications compared with patients who did not, no correlation was found between CCI and perioperative complications. However, past research has indicated that CCI could be used to predict perioperative complications in spinal surgeries.

“The ASA-PS are determined by anaesthesiologists considering not only types of comorbidity but also severity, which suggests that the ASA-PS could reflect the comorbidity status in more detail and more accurately than the CCI,” the authors said. “The subtle differences between these two criteria concepts might make a difference in the strength of their relevance to complications depending on the underlying disease such as RA.”

The authors also noted that patients who experienced complications generally had a shorter RA duration compared with patients who did not experience complications. However, there was a 2.5-year difference in the mean disease duration at time of surgery, and this difference will require more research to understand its clinical implications.

“Surgical intervention should be appropriately considered when patients have symptomatic AAS to prevent the progression of cervical spine lesions, and this approach could also prevent further perioperative complications that might occur in later surgery for more advanced cervical spine lesions,” the authors concluded.

Reference

Sakuraba K, Omori Y, Kai K, et al. Risk factor analysis of perioperative complications in patients with rheumatoid arthritis undergoing primary cervical spine surgery. Arthritis Res Ther. Published online March 31, 2022. doi:10.1186/s13075-022-02767-0