This study compared turnover times of endocrine procedures performed in an inpatient and outpatient OR. We showed that turnover times decrease significantly when comparing the inpatient and outpatient ORs, with reductions of nearly 20 minutes between cases. Turnover times were significantly lower when comparing each individual procedure turnover times, and were greatest when transitioning from a thyroid to a parathyroid procedure, or vice versa (). Additionally, the anesthesia time before the incision and the anesthesia time after incision closure were both significantly lower, which further accentuates the difference in turnover times.
Our data supports others that have found reduced anesthesia in-room time in an outpatient OR when compared to an inpatient OR12
. Our study showed a reduction in turnover times of nearly 20 minutes when comparing the inpatient to outpatient OR’s, which is similar to other studies, but the magnitude of reduction was greater. Kenyon et al
previously reported a reduction in turnover times of 7.1 minutes when changing from a standard OR to a minimally invasive suite13
. Though our data shows a greater reduction, this correlation between studies supports a universal reduction in turnover times when changing from an inpatient OR to an outpatient OR. These reductions in turnover times are often attributed to decreased case complexity and lower patient acuity. However, our study design showed that case mix, patient demographics and co-morbidities were similar between the inpatient and outpatient OR’s. Therefore, decreased case complexity and lower patient acuity are not the only factors contributing to the decreased turnover times. While our study focused only on parathyroid and thyroid procedures, so that we could control for case mix and complexity, we feel that these findings are likely generalizable to any procedure that could be performed in either an inpatient or outpatient setting (i.e laparoscopic cases, breast cases, skin cases, etc).
The total time difference of 23 minutes between the two groups in this study indicates significantly higher OR utilization in the outpatient OR. It is estimated that the cost of a single OR to a patient or health insurance provider is approximately $20 per minute14
. Therefore, a cost savings of $460 per procedure can be saved through overall time reductions when comparing the outpatient and inpatient ORs in this study. With an average of 3 to 4 endocrine cases performed per day in the outpatient OR during the study period, there could be a cost reduction between $1,380 and $1,840 per day through reductions in turnover times. Costs of additional medications, beds and additional staff should be added to the above1
, and can lead to an even greater cost savings.
While the costs directly associated with reduced turnover times are significant, the largest cost savings may come from reduced OR staffing15
. The lower turnover times achieved in the outpatient OR require less OR workload. Consequently, OR staffing costs can be reduced. It is estimated that a reduction in turnover times of 10 to 19 minutes would reduce OR staffing costs by 2.5% to 4.0%15
Recent studies have shown that turnover time improvement can result from a variety of factors. Turnover times were reduced by maintaining a fixed OR staff with dedicated manual tasks as well as instituting a more defined protocol for the OR staff2,16,17
. The greatest reductions in turnover times were observed when similar procedures were performed consecutively, as was the case in this study. Also, because nurses and physicians are generally employed by different entities, their motivation for shorter turnover times might not be the same16
. Turnover times can be reduced through OR staffing changes aimed at greater efficiency. At our institution the inpatient OR staff are on shifts. The outpatient OR uses a different staffing model that requires the staff only be present until the OR has been sterilized and prepared for the next day’s procedures. We believe that this difference in incentive has driven faster turnover times and improved OR efficiency at our institution, and should be researched in the future to determine if a similar staffing model in the inpatient OR could improve turnover times.
Whether reduced turnover time can lead to additional surgical cases remains a controversial topic. In a recent study, turnover times were reduced by 16 minutes after implementing a new staffing model. This resulted in one additional 90-minute procedure during the study16
. However, prior research showed that decreasing turnover time would only predictably allow an additional case if all procedures were consistently less than 75 minutes3,18
. The average case time of procedures performed in the outpatient OR for this study was 70 minutes. This indicates that another case could be added reliably in the outpatient OR.
Limitations of our study include the retrospective nature, the single institution, as well as the statistical differences between the groups at baseline. The inpatient OR group had a statistically higher ASA classification, was more likely to have an operative indication of cancer, to be a reoperative procedure and to have renal failure/insufficiency. These differences were likely due to selection bias, as the more complex cases were electively performed in the inpatient OR during the study period. While cancer and reoperative procedures likely impacted actual operative time, they should not have had a major impact on equipment needs or turnover time. Renal failure patients were done in the main operating room due to the need for dialysis in the immediate perioperative period. To try to control for these differences we did a multivariate analysis, which showed only ASA classification and indication of cancer remained significant. However, the inpatient/outpatient OR status showed a much stronger correlation to longer turnover times than either of these factors.
In conclusion, we found that thyroid and parathyroid procedures performed in an outpatient OR have shorter turnover times when compared to an inpatient OR. This improvement leads to decreased costs through reduced OR time and reduced staffing.