We welcome the comments of Drs. Dritz and Metz on our recent report1in Anesthesiology. All of the points they raise are valid and must be considered by any institution considering the future of its operating rooms (ORs). Dr. Dritz correctly points out that payer mix influences the cost–revenue balance of any perioperative system redesign that increases capital or operating costs. If a hospital is barely breaking even on its current case and payer mix, increasing costs so that more cases can be performed is a poor decision. However, we would not recommend abandoning the redesign of perioperative processes as a means to improve OR throughput. As we mentioned in our Discussion,1the Operating Room of the Future (ORF) is a single-OR research space with many purposes, one of which was to assess the financial impact of extensive physical plant reconfiguration to support parallel processing of perioperative tasks. Therefore, the ORF gains no advantages from the economies of scale that would accrue from even a two-room arrangement. We are aware of several parallel processing perioperative system design initiatives that involve no physical plant modifications or capital equipment purchases, and some of these are staff-level neutral.2Even in such instances, the payer mix strongly influences the results—it is still a poor decision to lose money faster by doing more cases per day if the payer mix is unfavorable. However, when the payer mix and revenue profile are favorable, perioperative system redesigns to achieve parallel processing and higher throughput at modest expense are clearly advantageous.

Dr. Dritz points out the value of block booking (i.e. , the practice of allocating a single OR to the same surgeon for a complete day with a full schedule) to enhance OR productivity. His experience of waiting for surgeons when switching surgeons between cases suggests that the surgical staff do not sufficiently appreciate the value of OR time or were not well informed about the OR's impending readiness for their cases. This experience should prompt the hospital to seek and correct the root cause of delays that involve waiting for surgeons, because the cost of unused OR time is prohibitive. As much as 50% of this cost is a variable cost that can be controlled by efficient use of OR time.3Failure to control such costs degrades the hospital's bottom line but has little impact on the surgeon. Therefore, with incentives misaligned, one worries that it might not be possible to improve performance. However, as we will describe in our response to Dr. Metz below, ORF initiatives may offer a solution.

Dr. Dritz further comments that one must be careful not to allow the productivity gains from parallel processing to be lost as downtime. Acknowledging this concern, it can be seen from table 2 of our work1that we were careful to use all of the 9-h workday in both the ORF and standard ORs, thus fully capturing the benefit of the increased capacity. Hospitals considering expending resources on perioperative system redesigns should carefully analyze both their case mix and their case volume before expending resources to enhance perioperative system capacity. The additional capacity should reduce staffing costs (by eliminating overtime or allowing a shorter work shift), allow complete additional cases to be performed, or both. Individual hospitals should apply their own financial frameworks for costs and revenues to the contemplated workflow changes before initiating a perioperative system redesign effort.

To address the concern that our institution-specific analysis is difficult to translate to other settings, we are reanalyzing the cost effectiveness of the ORF using national cost data. In this new analysis, the ORF is cost effective relative to standard ORs at our institution. In particular, the incremental cost of an additional case in the ORF is quite small—much smaller than the typical net margin for a simple general surgery case.4Therefore, we would challenge Dr. Dritz' final comment that the OR of the Future may not be economically viable in the present. If the incremental cost of an additional case performed in a high-throughput environment is smaller than the cost of a case that must be performed on a different day because the typical OR cannot accommodate it during regular work hours, the ORF is advantageous regardless of the payer mix.

Dr. Metz in his letter correctly identifies differences in practices and performance between surgeons as a major, and frequently the largest, single contributor to differences in OR throughput for a given list of cases. Although we agree that different surgeons have drastically different operative times for the same case type performed in the same patient population, we made a conscious decision to sidestep this issue. Dr. Metz endorses rewarding surgeons who meet benchmarks for operative time. However, structuring such rewards can be problematic. For example, simple financial incentives purely for speed may create conflicts related to quality and patient safety. On the other hand, the ORF project described in our article offers several incentives for superior operative time performance: a small, dedicated team, rapid turnovers, and brief nonoperative times that translate into on-time completion of workdays and extra throughput. By focusing on nonoperative time and by reducing the nonoperative time by restructuring workflow rather than pressuring OR staff to hurry, the ORF creates an environment in which patient contact time and safety are preserved while productivity is enhanced. Because the enhancement in productivity comes almost exclusively from better nonoperative performance, cases with shorter operative times capture the most benefit from the ORF. This logical and inescapable conclusion dictates that block time in high-throughput environments be given preferentially to the most efficient surgeons. Therefore, an OR suite with a few high-capacity ORs such as our ORF gives administrators a tool to reward desirable performance, while creating incentives for other surgeons to improve operative times, all the while preserving the safety and quality profile for the hospital's patients.

*Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts. wsandberg@partners.org

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Stahl JE, Sandberg WS, Daily B, Wiklund RA, Egan MT, Goldman JM, Isaacson KB, Gazelle S, Rattner DW: Reorganizing patient care and workflow in the operating room: A cost-effectiveness study. Surgery 2006:(in press)