Lay Summary by Fatima Waqar
Edited by Rona Herzog
What are Perioperative Adverse Events? Why is it important to study their effect on long-term patient outcome?
For the purposes of this study, adverse events (AEs) are defined as incidents that happen during a patients’ initial operation or throughout their hospital admission prior to their discharge. AEs are further categorized as minor and major depending on how much of a threat they may impose on an individual’s life or overall health.
AEs have been associated with patient disappointment, as they have the potential to negatively impact an individual’s physical function. It is important to note that the financial burden of AEs after spinal surgery is well identified in research, but very little is still known about how these events affect the well-being and quality of life of patients. One factor that may impact the lack of significant research on AEs and patients’ quality of life is the generalizability of the findings. Because many studies have smaller and less diverse sample sizes, using a single approved definition of AE can make it easy for the researchers to generalize their findings to the greater community.
What is the purpose of the study?
The purpose of this study is to determine how AEs that occur during lumbar spine surgeries affect patients’ satisfaction and quality of life at three distinct time intervals after surgery. Researchers followed up with patients at 3, 12, and 24 months after their surgeries.
How was this study conducted?
Patients included in the study were individuals undergoing elective surgery for degenerative lumbar spine conditions (lumbar disc disease, degenerative spondylolisthesis, spinal stenosis, and isolated lumbar degenerative deformity).
A total of 3556 adult patients (18 years and older) enrolled in the Canadian Spine Outcomes and Research Network (CSORN) were studied. AEs were defined using the Spinal Adverse Events Severity System (SAVES-V2). Researchers also used multiple surveys and scales to measure the patient’s well-being and quality of life over the 3, 12, 24 month intervals. Those measurements included the Oswestry Disability Index (ODI), 12-Item Short-Form Health Survey (SF-12) Physical (PCS) and Mental (MCS) Component Summary Scales, Visual Analog Scale (VAS) leg and back, EuroQol-5D (EQ5D), and satisfaction.
What did the researchers discover?
Findings from the study showed that
- 2789 (78.4%) patients experienced no AE
- 85 (2.4%) patients had at least 1 major AE
- 682 (19.2%) patients experienced minor AEs only
Researchers also determined multiple factors influencing the potential for patients to develop a major AE, which include:
- increased age
- fusion surgery
- patient’s overall health, measured via ASA Score (>2)
- increased blood loss during surgery
- increased surgical time by 1-min intervals
Important predictors found for minor AEs include:
- increased age
- lumbar degenerative deformity (age related wear and tear of the lower back or lumbar spine)
- fusion surgery
- increased surgical time
What do these findings mean for individuals in the community?
After lumbar surgery, a higher proportion of patients with major or minor AEs require care in an intensive care or a step-down unit, they also have longer hospital stays, and are less likely to be directly discharged to home as compared to those without an adverse event.
At 12 and 24 month follow-up after surgery, non-satisfaction and negative effects on physical function and quality of life were the highest among patients with major AEs.
What can be done to improve long term patient outcome?
- It will be important moving forward that patients undergoing surgery for degenerative lumbar spine conditions are informed that minor AEs are relatively common but are unlikely to affect quality of life, whereas major AEs are relatively rare but have the potential to reduce physical functioning if they occur.
- Surgeons are made aware of the impacts of AEs and they should work towards developing practices to minimize AEs in those patients requiring more complex procedures.