Acute adverse events associated with ventral slot decompression in 546 dogs with cervical intervertebral disc disease.

OBJECTIVE

To report the frequency, types, and risk factors for acute perioperative adverse events (AEs) in dogs that had ventral slot decompression (VSD) for cervical intervertebral disc disease (IVDD).

DESIGN

Retrospective, case-control study.

ANIMALS: Dogs (n = 546) with cervical IVDD treated by VSD; 54 cases experiencing AE and 492 controls.

METHODS

Historical, clinical, diagnostic, operative, and outcome data were collected. AE were graded using a Spine Adverse Events Severity (SAVES) system. Associations between the development of AE and hypothesized risk factors were analyzed using bi- and multi-variable analyses.

RESULTS

AE were observed in 54 dogs (9.9%). Minor AE (SAVES Grade 1-2) occurred in 3.5% (19 dogs) and major (SAVES Grades 3-5) AE in 6.4% (35 dogs). Deterioration in neurologic status (n = 13), persistent pain (12), and intraoperative hemorrhage (7) were common major AE. NSAID administration, surgeon experience, C7-T1 disc location, and intraoperative hypotension were significantly associated with AE in multivariate analyses. Improvement of AE occurred in 48/54 (88.9%) of cases, although reoperative neurosurgery was required in 48.5% (17/35) of dogs experiencing major AE. Dogs with major AE had significantly longer hospitalization and worse outcomes than dogs with minor AE or controls. No fatal AE occurred, although 0.7% (4/546) of dogs were euthanatized postoperatively.

CONCLUSIONS

AE occurred in 9.9% of dogs that had VSD, and were significantly associated with perioperative hypotension, C7-T1 disc extrusions, surgeon experience, and NSAID usage. Identification of a major postoperative AE is an indication for immediate diagnostic imaging studies, as 50% of dogs experiencing major AE required reoperation.