Spine adverse events severity system: content validation and interobserver reliability assessment.

STUDY DESIGN: A prospective validation study, preliminary single-center report. OBJECTIVE: The purpose of this study was to assess the content validity and interobserver reliability of a simple severity classification system for adverse events (AEs) associated with spinal surgery. SUMMARY OF BACKGROUND DATA: In the surgical literature what is defined as an AE, the severity of an AE, and the reporting of AEs are variable. Consequently, valid comparison of AEs within or among specialties or surgical centers for the same or different procedures is often impossible. METHODS: Since 2002, a Spine Adverse Events Severity system (SAVES) has been locally developed and prospectively used. AEs were graded as I (requires none/minimal treatment, minimal effect [<1-2 days] on length of stay [LOS]), II (requires treatment and/or increases LOS [3-7 days] with no long-term sequelae), III (requires treatment and/or increased LOS [>7 days] with long-term sequelae [>6 months]), and IV (death). Content validity of the grading system was assessed using the hospital chart abstraction (current defacto gold standard) compared with the SAVES from 200 randomly selected patients. Interobserver reliability was assessed in consecutive operative cases for 1 spine surgeon during a 1-year period (2006) using 3 raters (staff surgeon, fellow, and/or resident). RESULTS: The prospectively administered form reported a higher number of surgical AEs (n = 43 vs. n = 30) and a similar number of medical AEs (n = 31 vs. n = 27). Compared with the chart, the AE form displayed substantial agreement for number (70%; weighted Kappa [wK] = 0.60) and type (75%; wK = 0.67) of AE. The interobserver reliability was near perfect (kappa = 0.8) for the actual grade of AE and moderate (kappa = 0.5) for the criteria behind the grading (i.e., clinical effect of the AE or the effect of the AE on LOS or both). CONCLUSION: The result of this study demonstrates improved capture of surgical AEs using SAVES. Excellent interobserver reliability between surgeons at different level of training was demonstrated with minimal education or training regarding the use of SAVES.

Intraoperative adverse events and related postoperative complications in spine surgery: implications for enhancing patient safety founded on evidence-based protocols.

STUDY DESIGN: Prospective observational study. OBJECTIVE: To assess the incidence and clinical consequence of intraoperative adverse events from a wide variety of spinal surgical procedures. SUMMARY OF BACKGROUND DATA: In this study, adverse events were defined as any unexpected or undesirable event(s) occurring as a result of spinal surgery. A complication was defined as a disease or disorder, which, as a consequence of a surgical procedure, will negatively affect the outcome of the patient. We hypothesized that most adverse events would not result in complications that would be normally flagged through traditional practice audit approaches. By defining the incidence and types of adverse events seen in a spine surgical practice, we hope to develop preventative approaches to enhance patient safety. METHODS: All postoperative clinical sequelae (i.e., complications) were prospectively identified, classified as to type, and graded (0 [none] to IV [death]) in 700 consecutive patients who underwent spine surgery (excluding > 300-day surgery microdiscectomies) at a university center from January 2002 to June 2003. To confirm data accuracy and assess the clinical sequelae of any adverse events, the medical records of these 700 patients were reviewed. RESULTS: The overall incidence of intraoperative adverse events was 14% (98/700). A total of 23 adverse events led to postoperative clinical sequelae for an overall intraoperative complication incidence of 3.2% (23/700). Specific adverse events included dural tears (n = 58), spinal instrumentation-related events (n = 12), blood loss exceeding 5000 mL (n = 10), anesthesia/medical (n = 4), suspected or actual vertebral artery injury (n = 3), approach-related events (n = 3), esophageal/pharyngeal injury (n = 2), and miscellaneous (n = 6). CONCLUSIONS: Adverse events can frequently occur (14%) during spinal surgery, however, the majority (76.5%) are not associated with complications. Improved patient safety can only be maximized by independent practice audit and the development of prospective methods to record adverse event data so that enhanced, evidence-based, clinical protocols can be developed.