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IIR 05-296 – HSR Study

IIR 05-296
Surgical Case Duration in the Department of Veterans Affairs
Brian Austin Cason, MD
San Francisco VA Medical Center, San Francisco, CA
San Francisco, CA
Funding Period: April 2007 - March 2009
Operating room (OR) time is a scarce and expensive resource that may account for 33% or more of the costs of providing care to surgical patients. OR time must therefore be utilized efficiently to optimizedelivery of surgical care. A finding of significant variation among institutions in the use of expensive OR resources (for similar cases) may indicate important opportunities to improve structure or processes of care.

This study will make innovative use of existing VA data sources: (1) To measure national and regional reference values for surgical case length for common operative procedures within VA, and to determine risk-adjusted case lengths. These data will be used to identify institutional variations in care. (2) To
characterize the risk-adjusted case-volume:surgical-time relationship for common operations, and to determine whether high-volume hospitals deliver surgical care more efficiently. (3) To validate methods for automated measuring and tracking of measures of OR efficiency.

Data are drawn from the National Surgical Quality Improvement Program (NSQIP) database and from the VA VistA surgical package. Multivariate, hierarchical regression methods are used to identify risk factors for surgical case duration. Models are developed to measure the effects of patient-level factors, hospital level factors, and clustering of outcomes at the institutional level. To address specific goal of refining methods for automated measuring and tracking of measures of OR fficiency, Operating Room workload and throughput data is drawn from the VistA Surgical Package. SAS programs have been written to generate, in a highly-automated and user-friendly fashion, a series of monthly reports useful to Operating Room Managers, Operating Room Committees, and Chiefs of
Anesthesia and of Surgery. Monthly reports address: OR utilization, block time utilization, start time tardiness, reasons for start time delays, turnover times, and scheduling accuracy. The reliability of this system for automatically identifying OR "start" cases and OR "turnovers" is high, greater than 95%.

Radical Retropubic Prostatectomy (RPP) surgeries performed within VA were reviewed. Between October 1,2001 and September 30, 2004, a total of 5,070 RRP surgeries met inclusion criteria. After adjustment for case-mix, academic training institutions had longer operative times (3.2 hours vs 2.4 hours, p <0.01) but shorter length of stay (3.4 days vs 4.2 days, p <0.01). Surgery at academic
institutions was not associated with greater risk of transfusion (p= 0.36), reoperation (p = 0.93), complications (p = 0.53) or readmissions (p = 0.97). Among the academic institutions, however, low versus high hospital RRP volume was associated with longer LOS (3.7 vs 3.1 days, p = 0.02) and higher transfusion rate (29.6% vs 18.2%, p = 0.02). Within the VA system, academic training institutions have longer operative times for RRP, but shorter LOS. Among the same institutions, high-volume hospitals tend to have lower transfusion rates and shorter LOS. Clustering of outcomes at the hospital level suggests that unmeasured institutional factors are key determinants of clinical and resource-related outcomes. Regarding the effects of anesthetic technique on patient outcomes, we have found that regional
anesthesia is infrequently used as a primary technique for RRP within the VA system. Clinical
outcomes of transfusion, length of stay, complication rate, reoperations, and readmissions are generally
similar for patients receiving GA vs RA.
Regarding our third objective, we have developed and validated methods for automated measuring and
tracking of measures of OR efficiency, including: OR utilization, block time utilization, cancellation rate,
on-time starts, turnover time, and case duration scheduling accuracy. The reliability of this system for
automatically identifying OR "start" cases and OR "turnovers" is high, greater than 95%.
The project continues with the aim of benchmarking of surgical times at academic and non-academic
institutions at the national level.

1. By using the suite of SAS routines which we have developed, operating room managers can readily produce management reports which facilitate efficient management of VA Operating Room resources.

2. Our studies point out the importance of developing a database of local, historical surgical case durations at each VA Medical Center, as surgical case duration appears to be highly dependent upon local factors, rather than patient factors.

External Links for this Project

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Journal Articles

  1. Ku TS, Kane CJ, Sen S, Henderson WG, Dudley RA, Cason BA. Effects of hospital procedure volume and resident training on clinical outcomes and resource use in radical retropubic prostatectomy surgery in the Department of Veterans Affairs. The Journal of urology. 2008 Jan 1; 179(1):272-8; discussion 278-9. [view]
  2. Vasilevskis EE, Kuzniewicz MW, Cason BA, Lane RK, Dean ML, Clay T, Rennie DJ, Vittinghoff E, Dudley RA. Mortality probability model III and simplified acute physiology score II: assessing their value in predicting length of stay and comparison to APACHE IV. Chest. 2009 Jul 1; 136(1):89-101. [view]
Journal Other

  1. Guy TS, Kelly MP, Cason B, Tseng E. Retrograde cerebral perfusion and delayed hyperbaric oxygen for massive air embolism during cardiac surgery. Interactive cardiovascular and thoracic surgery. 2009 Mar 1; 8(3):382-3. [view]
Conference Presentations

  1. Cason BA. Diagnosis of PTSD is associated with increased 1- and 5-year mortality. Presented at: American Society of Anesthesiologists Annual Meeting; 2009 Oct 17; New Orleans, LA. [view]

DRA: Health Systems
DRE: none
Keywords: Care Management, Clinical practice guidelines, Utilization patterns
MeSH Terms: none

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