Secondary Logo

Journal Logo

Editorials: Editorial

A Brief History of Evidence-Based Operating Room Management

Then and Now

Dexter, Franklin MD, PhD

Author Information
doi: 10.1213/ANE.0b013e31824cba97
  • Free

Organization of a Hospital Anesthesia Department

Caroline B. Palmer, M.D., San Francisco, Calif. Chief of Anesthesia Service, Lan Hospital.

Then In 1923, Caroline Palmer described anesthesia department managerial responsibilities for operating room anesthesia1:

“The functions of a department of anesthesia may reasonably include:— (1) Provision of qualified anesthetists for routine and emergency operations. (2) Such assignment of work that the experience and skill of each anesthetist may be equal to the requirements of his task. (3) Arrangement for reasonable compensation for each member of the department. (4) Sufficient care to guarantee the perfect working order of all apparatus. (5) A personal attention to necessary supplies to insure an adequate amount and prevent waste. (6) Obtaining a knowledge of the patient's physical condition sufficient to enable the anesthetist to consult intelligently with the surgeon as to choice of anesthetic. (7) Cooperation with surgeon and nurses in all matters which have a bearing upon the welfare of patients, before, during and after anesthesia. (8) Provision for obstetrical anesthesia and analgesia. (9) Taking advantage of every opportunity for giving instruction in anesthesia, to the end that progress may be made toward the day when this branch of medical practice may keep pace with the advances being made in other departments. (10) Keeping an accurate record of each anesthesia and making all desirable reports to the hospital authorities.”

These functions seem to me to be nearly indistinguishable from those of the University of Iowa's Department of Anesthesia when I joined as a resident physician in 1990.

Now Modern anesthesia departments are different. To understand the change, consider a few sentences of detail from Palmer's 1923 paper1:

“The anesthetist in charge … obtains each morning from the night superintendent of nurses the schedule of the day's operations. The anesthetist then telephones to each ward having patients for operation and obtains necessary information regarding such patients.”

The sole operational (industrial engineering) decision to be made by the anesthetist in charge was staff assignment. The managerial complexity was handled before the anesthetist was involved through the process of patient hospital admission. Control of hospital beds effectively controlled the operating rooms (ORs). For example, suppose that orthopedics had 15 beds. Then, there were literally (physically) 15 beds for the night. Surgery was limited to no more than 15 new patients. That is unlike operating rooms for which overutilized time is a conceptual model.24

If based on historical workload, the staffing for an OR is appropriately planned to be 8 hours, then work beyond 8 hours is overutilized time. The only limit would be if the OR was used until the next morning. Usage of hospital beds for surgical patients now is effectively controlled by the OR schedule, not vice versa.5

Scientific management of hospital bed occupancy had become sophisticated by the late 1960s, with practical statistical methods.68 Consideration of percentage occupancy for managerial control of specialties' beds was not just a political rule of thumb. The appropriate number of beds for each specialty, calculated based on each specialty's percentage occupancy, are mathematically optimal.17,9

Applying the same principle to OR capacity (aka, percentage utilization) results in solutions that are highly suboptimal (i.e., planned amounts of OR time are too high or low).24 Intuitively, this is because beds are physically full, whereas ORs are not (i.e., occupancy/utilization routinely exceeds 100%). The only exceptions are facilities with very low workloads per OR daily and yet every OR is planned for a minimum of 8 hours, because then occupancy/utilization would virtually never exceed 100%. Regardless, when percentage occupancy (i.e., utilization) is applied to the OR time of individual surgeons, it is impossible to make decisions without a large (>10%) probability of decisions being no better than making the decision by random choice.10,11 Furthermore, decisions based on increasing OR utilization typically are no better than random choice at resulting in increased margin sufficient to pay for fixed costs such as buildings and information systems.12

Same day admit surgery and outpatient surgery have had profound implications for the managerial responsibilities of anesthesiologists. Administrators' purview of bed management no longer provides managerial control of surgery, since most surgical facilities nationwide are outpatient centers,13 most surgical visits are outpatient,13 and even at hospitals, less than one-quarter of the patients are admitted before their scheduled procedures14. OR nursing directors' bases for compensation and evaluation rarely are based on patient scheduling and management science.15 Consequently, informed anesthesia department management has changed since Palmer's article.1 Anesthesia departments should be implementing the developed operations research to be making evidence-based management decisions.25,10,12


Name: Franklin Dexter, MD, PhD.

Contribution: This author designed the study, conducted the study, and wrote the manuscript.

Attestation: Franklin Dexter has approved the final manuscript.

Conflicts of Interest: The University of Iowa, Department of Anesthesia, Division of Management Consulting, performs operations research analyses for anesthesia groups and hospitals and provides education (class). Franklin Dexter receives no funds personally from such activities. He has tenure and does not participate in any incentive programs. Income from the Division's consulting work is used to fund research.

This manuscript was handled by: Steven L. Shafer, MD.

“All we know about the world teaches us that the effects of A and B are always different—in some decimal place—for any A and B. Thus asking ‘Are the effects different?' is foolish.” —John Tukey (The philosophy of multiple comparisons. Stat Sci 1991;6:100–16)


1. Palmer CB. Organization of a hospital anesthesia department. Anesth Analg 1923;2:50–5
2. Strum DP, Vargas LG, May JH, Bashein G. Surgical suite utilization and capacity planning: a minimal cost analysis model. J Med Syst 1997;21:209–22
3. McIntosh C, Dexter F, Epstein RH. Impact of service-specific staffing, case scheduling, turnovers, and first-case starts on anesthesia group and operating room productivity: tutorial using data from an Australian hospital. Anesth Analg 2006;103:1499–516
4. Wachtel RE, Dexter F. Review of behavioral operations experimental studies of newsvendor problems for operating room management. Anesth Analg 2010;110:1698–710
5. Vanberkel PT, Boucherie RJ, Hans EW, Hurink JL, van Lent WA, van Harten WH. Accounting for inpatient wards when developing master surgical schedules. Anesth Analg 2011;112:1472–9
6. Young JP. Stabilization of inpatient bed occupancy through control of admissions. Hospitals 1965;39(19):41–8
7. Young JP. Administrative control of multiple-channel queuing systems with parallel input streams. Oper Res 1966;14:145–56
8. Shonick W. A stochastic model for occupancy-related random variables in general-acute hospitals. J Am Stat Assoc 1970;65:1474–500
9. McManus ML, Long MC, Cooper A, Litvak E. Queuing theory accurately models the need for critical care resources. Anesthesiology 2004;100:1271–6
10. Dexter F, Macario A, Traub RD, Hopwood M, Lubarsky DA. An operating room scheduling strategy to maximize the use of operating room block time: computer simulation of patient scheduling and survey of patients' preferences for surgical waiting time. Anesth Analg 1999;89:7–20
11. Dexter F, Traub RD, Macario A, Lubarsky DA. Operating room utilization alone is not an accurate metric for the allocation of operating room block time to individual surgeons with low caseloads. Anesthesiology 2003;98:1243–9
12. Wachtel RE, Dexter F. Tactical increases in operating room block time for capacity planning should not be based on utilization. Anesth Analg 2008;106:215–26
13. Cullen KA, Hall MJ, Golosinskiy A. Ambulatory Surgery in the United States, 2006. National health statistics reports; no 11. Revised. Hyattsville, MD: National Center for Health Statistics, 2009
14. O'Neill L, Dexter F, Wachtel RE. Should anesthesia groups advocate funding of clinics and scheduling systems to increase operating room workload? Anesthesiology 2009;111:1016–24
15. Masursky D, Dexter F, Nussmeier NA. Operating room nursing directors' influence on anesthesia group operating room productivity. Anesth Analg 2008;107:1989–96
© 2012 International Anesthesia Research Society