Introduction: Efficient operating room time use is important in modern medicine, as delays in patient arrival, anesthesia induction, surgical positioning, and recovery in the operating room all increase OR time not spent operating. In this study we sought to determine what factors increase anesthetized, non-operative time, and how significantly by utilizing a database of over 5,000 consecutive neurosurgical spine cases at our institution.
Methods: Surgical records were searched in a retrospective fashion to identify all spine surgeries performed between January 2010 and July 2012. Anesthetized, non-operative time was calculated from the anesthesia record, and was compared to both patient and procedure characteristics to determine any significant relationships
Results: There were 5515 surgical cases with a mean age of 60.5, mean BMI of 29.7 and 3226 (58%) were male. There were 1176 (21%) fusion cases, and level of pathology was predominantly lumbar (4010 cases, 73%). Fusion cases had a significantly longer total anesthetized, non-operative time when compared to non-fusion cases (Fusion – 98 minutes vs. Non-fusion – 76 minutes, mean difference – 22 minutes, p<0.0001). Significant factors affecting anesthetized, non-operative time in non-fusion cases include age greater than 65 (mean difference – 5 minutes, p<0.0001), ASA grade, and BMI (<25 – 72 +/- 1.2 minutes vs. 25-29 - 74 +/- 0.6 minutes vs. 30-39 - 79 +/- 0.6 minutes vs. 40+ - 87 +/- 1.8 minutes, p<0.0001). Age, ASA grade and BMI all maintained significance on multivariate analysis. Similarly, for fusion operations, age >65 was significantly associated with increased non-operative time (mean difference – 6 minutes, p<0.01), increasing ASA (mean difference 9 minutes, p<0.0001) and increasing BMI. Age, ASA grade and BMI all maintained significance on multivariate analysis.
Conclusions: Patient and surgical factors, such as age, ASA grade, BMI, level of pathology and surgical approach have noticeable effects on anesthetized, non-operative times in spine surgery.
Patient Care: This research will improve patient care by identifying areas for improvement in operating room time utlilization and identifying patient/procedure specific factors that influence non-operative time. This could lead to interventions whereby specific patients are listed as "high efficiency" patients, receiving complex access and monitoring in the pre-operative area rather than waiting to perform all of these procedures after anesthetic induction
Learning Objectives: By the conclusion of this session, participants should be able to 1) Identify patient specific factors that increase anesthetized, non-operative time in spine surgery, 2) Identify procedure specific factors that increase this time and 3) Identify areas for improvement and incrased efficiency within the OR patient flow
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