Legal and ethical implications of defining an optimum means of achieving unconsciousness in assisted dying.

A decision by a society to sanction assisted dying in any form should logically go hand-in-hand with defining the acceptable method(s). Assisted dying is legal in several countries and we have reviewed the methods commonly used, contrasting these with an analysis of capital punishment in the USA. We expected that, since a common humane aim is to achieve unconsciousness at the point of death, which then occurs rapidly without pain or distress, there might be a single technique being used. However, the considerable heterogeneity in methods suggests that an optimum method of achieving unconsciousness remains undefined. In voluntary assisted dying (in some US states and European countries), the common method to induce unconsciousness appears to be self-administered barbiturate ingestion, with death resulting slowly from asphyxia due to cardiorespiratory depression. Physician-administered injections (a combination of general anaesthetic and neuromuscular blockade) are an option in Dutch guidelines. Hypoxic methods involving helium rebreathing have also been reported. The method of capital punishment (USA) resembles the Dutch injection technique, but specific drugs, doses and monitoring employed vary. However, for all these forms of assisted dying, there appears to be a relatively high incidence of vomiting (up to 10%), prolongation of death (up to 7 days), and re-awakening from coma (up to 4%), constituting failure of unconsciousness. This raises a concern that some deaths may be inhumane, and we have used lessons from the most recent studies of accidental awareness during anaesthesia to describe an optimal means that could better achieve unconsciousness. We found that the very act of defining an 'optimum' itself has important implications for ethics and the law.

Hospitals with briefer than average lengths of stays for common surgical procedures do not have greater odds of either re-admission or use of short-term care facilities.

We considered whether senior hospital managers and department chairs need to be concerned that small reductions in average hospital length of stay (LOS) may be associated with greater rates of re-admission, use of home health care, and/or transfers to short-term care facilities. The 2013 United States Nationwide Readmissions Database was used to study surgical Diagnosis Related Groups (DRG) with 1) national median LOS ≥3 days and 2) ≥10 hospitals in the database that each had ≥100 discharges for the DRG. Dependent variables were considered individually: 1) re-admission within 30 days of discharge, 2) discharge disposition to home health care, and/or 3) discharge disposition of transfer to short-term care facility (i.e., inpatient rehabilitation hospital or skilled nursing facility). While controlling for DRG, each one-day decrease in hospital median LOS was associated with an odds of re-admission nationwide of 0.95 (95% confidence interval [CI] 0.92-0.99; P=0.012), odds of disposition upon discharge being home care of 0.95 (95% CI 0.83-1.10; P=0.64), and odds of transfer to short-term care facility of 0.68 (95% CI 0.54-0.85; P=0.0008). Results were insensitive to the addition of patient-specific data. In the USA, patients at hospitals with briefer median LOS across multiple common surgical procedures did not have a greater risk for either hospital re-admission within 30 days of discharge or transfer to an inpatient rehabilitation hospital or a skilled nursing facility. The generalisable implication is that, across many surgical procedures, DRG-based financial incentives to shorten hospital stays seem not to influence post-acute care decisions.

IL-4 mediated by HSV vector suppresses morphine withdrawal response and decreases TNFα, NR2B, and pC/EBPß in the periaqueductal gray in rats.

Chronic opiates induce the development of physical dependence. Opioid physical dependence characterized by withdrawal symptoms, may have very long-lasting effects on the motivation for reward, including the incubation of cue-induced drug-seeking behavior. Elucidation of the mechanisms involved in physical dependence is crucial to developing more effective treatment strategies for opioid dependence. Chronic morphine induces production of proinflammatory cytokines in regional-specific sites of the brain. Interleukin-4 (IL-4) is a prototypical anti-inflammatory cytokine that globally suppresses proinflammatory cytokines. Here, we used recombinant herpes simplex virus vector S4IL4 that encode mouse il4 gene to evaluate the therapeutic potential of IL-4 in naloxone-precipitation morphine withdrawal (MW). One week after microinjection of the vector S4IL4 into the PAG LacZ or mouse IL-4 immunoreactivity in the vlPAG was visualized. ELISA assay showed that vector S4IL4 into the PAG induced the expression of IL-4. S4IL4 blunted the morphine withdrawal syndrome. S4IL4 suppressed the upregulated TNFα, NR2B and pC/EBPß in the PAG induced by MW. These results show that inhibition of proinflammatory factor in the PAG suppressed MW. This study may provide a novel therapeutic approach to morphine physical withdrawal symptoms.

HSV vector-mediated GAD67 suppresses neuropathic pain induced by perineural HIV gp120 in rats through inhibition of ROS and Wnt5a.

Human immunodeficiency virus (HIV)-related neuropathic pain is a debilitating chronic condition that is severe and unrelenting. Despite the extensive research, the exact neuropathological mechanisms remain unknown, which hinders our ability to develop effective treatments. Loss of GABAergic tone may have an important role in the neuropathic pain state. Glutamic acid decarboxylase 67 (GAD67) is one of the isoforms that catalyze GABA synthesis. Here, we used recombinant herpes simplex virus (HSV-1) vectors that encode gad1 gene to evaluate the therapeutic potential of GAD67 in peripheral HIV gp120-induced neuropathic pain in rats. We found that (1) subcutaneous inoculation of the HSV vectors expressing GAD67 attenuated mechanical allodynia in the model of HIV gp120-induced neuropathic pain, (2) the anti-allodynic effect of GAD67 was reduced by GABA-A and-B receptors antagonists, (3) HSV vectors expressing GAD67 reversed the lowered GABA-IR expression and (4) the HSV vectors expressing GAD67 suppressed the upregulated mitochondrial superoxide and Wnt5a in the spinal dorsal horn. Taken together, our studies support the concept that recovering GABAergic tone by the HSV vectors may reverse HIV-associated neuropathic pain through suppressing mitochondrial superoxide and Wnt5a. Our studies provide validation of HSV-mediated GAD67 gene therapy in the treatment of HIV-related neuropathic pain.

HSV-mediated p55TNFSR reduces neuropathic pain induced by HIV gp120 in rats through CXCR4 activity.

Human immunodeficiency virus (HIV)-related neuropathic pain is a debilitating chronic condition that is severe and unrelenting. Despite extensive research, the detailed neuropathological mechanisms remain unknown, which hinders our ability to develop effective treatments. In this study, we investigated the role of proinflammatory molecules, tumor necrosis factor-α (TNFα), CXCR4 and stromal-derived factor-1 α (SDF1α), in the L4/5 dorsal root ganglia (DRG) and the spinal dorsal horn in HIV gp120 protein-mediated neuropathic pain. Our results showed that the application of HIV gp120 to the sciatic nerve induced upregulation of TNFα, CXCR4 and SDF1α in both the DRG and the lumbar spinal dorsal horn. Non-replicating herpes simplex virus (HSV) vector encoding the p55TNFSR gene and producing a TNF-soluble receptor (TNFSR) to block bioactivity of TNFα reversed mechanical allodynia. Intrathecal AMD3100 (CXCR4 antagonist) increased mechanical threshold. The HSV vectors expressing p55TNFSR reversed upregulation of TNFα, CXCR4 and SDF1α induced by gp120 in the DRG and the spinal dorsal horn. These studies suggest that proinflammatory TNFα to the CXCR4/SDF1 pathway has an important role in the HIV-related neuropathic pain state and that blocking the proinflammatory cytokines or chemokines is able to reduce neuropathic pain. This work provides a novel gene therapy proof-of-concept for HIV-associated neuropathic pain.

Nicardipine reverses vasoactivity associated with University of Wisconsin solution in the rat peripheral circulation.

BACKGROUND: The rapid uniform delivery of University of Wisconsin solution (UW) to the microcirculation may be compromised by its vasoactivity. METHODS: In 2 different rodent models, we tested whether UW-mediated vasoconstriction could be reversed with nicardipine. RESULTS: In the perfused, splanchnic circulation, intravascular control solutions (lactated Ringers [LR], Hextend [HEX], histidine-tryptophan-ketoglutarate [HTK]) or UW (± nicardipine) evoked pressure changes in 3 protocols (series 1; n = 35). In the cremaster muscle, topical control solutions or UW (± nicardipine) evoked vascular responses measured by video microscopy in 4 protocols (series 2; n = 47). In series 1A, 37°C UW increased perfusion pressure, but there was no change caused by LR, HEX, or HTK. In series 1B, 4°C UW caused a similar, albeit transient, increase. In series 1C, nicardipine reversed 37°C UW-mediated vasoconstriction in a dose-related manner. In series 2A, UW caused a 30%-59% constriction that varied with arteriolar branching order. In series 2B, the recovery from UW-induced vasoconstriction varied with duration of exposure, but nicardipine fully reversed residual vasoconstriction. In series 2C, cold and warm UW were equipotent, near maximal, vasoconstrictors. In series 2D, UW potentiated no-reflow. CONCLUSION: UW causes a potent temperature-independent vasoconstriction by a calcium-mediated mechanism and this effect can be mitigated with nicardipine.

Patient preferences for acute pain treatment.

BACKGROUND: Optimal treatment for acute pain is a function of an individual's willingness to make trade-offs between treatment side effects and pain control. The objective was to investigate the degree to which patients are willing to make these trade-offs. METHODS: Fifty patients undergoing major abdominal surgery were enrolled and completed interviews before and after surgery. Measures included an experience with pain questionnaire and an adaptive conjoint analysis (ACA) interview. RESULTS: Percentage of pain relief obtained post-surgery was between 70 and 80%. Eight-two per cent reported at least one moderate or severe side effect. ACA results demonstrated that pain efficacy and side effect type/severity have almost equal 'importance' scores. Patients varied in their willingness to trade-off pain efficacy for different or milder side effects. CONCLUSIONS: We conclude that people have different relative preferences for different side effects and are willing to trade-off pain relief for less upsetting and/or less severe side effects but to different degrees. Thus, physicians should consider offering pain medications with fewer side effects than narcotics as a first choice. Our study indicates the need to balance analgesia and side effects in order for patients to achieve optimal pain control.

The impact on revenue of increasing patient volume at surgical suites with relatively high operating room utilization.

UNLABELLED: We previously studied hospitals in the United States of America that are losing money despite limiting the hours that operating room (OR) staff are available to care for patients undergoing elective surgery. These hospitals routinely keep utilization relatively high to maximize revenue. We tested, using discrete-event computer simulation, whether increasing patient volume while being reimbursed less for each additional patient can reliably achieve an increase in revenue when initial adjusted OR utilization is 90%. We found that increasing the volume of referred patients by the amount expected to fill the surgical suite (100%/90%) would increase utilization by <1% for a hospital surgical suite (with longer duration cases) and 4% for an ambulatory surgery suite (with short cases). The increase in patient volume would result in longer patient waiting times for surgery and more patients leaving the surgical queue. With a 15% reduction in payment for the new patients, the increase in volume may not increase revenue and can even decrease the contribution margin for the hospital surgical suite. The implication is that for hospitals with a relatively high OR utilization, signing discounted contracts to increase patient volume by the amount expected to "fill" the OR can have the net effect of decreasing the contribution margin (i.e., profitability). IMPLICATIONS: Hospitals may try to attract new surgical volume by offering discounted rates. For hospitals with a relatively high operating room utilization (e.g., 90%), computer simulations predict that increasing patient volume by the amount expected to "fill" the operating room can have the net effect of decreasing contribution margin (i.e., profitability).

Cost identification analysis for succinylcholine.

UNLABELLED: The cost of a dose of succinylcholine from society's perspective equals the acquisition cost of the drug plus the cost of its adverse outcomes. We hypothesized that although the acquisition cost of succinylcholine is minimal, the true cost would be much larger. We reviewed the medical literature to identify the total cost of a dose of succinylcholine when administered for nonemergency purposes according to manufacturers' guidelines (i.e., to adults only). We found that 88% of the cost per dose of succinylcholine was for the chance of dying or sustaining permanent brain injury from anaphylactic or anaphylactoid reactions to succinylcholine. Consequently, the estimated cost per dose of succinylcholine was sensitive to the incidence of anaphylactic or anaphylactoid reactions to succinylcholine, the risk of severe injury from anaphylactic or anaphylactoid reactions, and the financial value of unforeseen instant death or permanent brain injury. The range for the cost per dose of succinylcholine was thus large, $9 to $93. Our best estimate of the cost per dose was $37. We conclude that the true cost per dose of succinylcholine from society's perspective is more than 20 times the acquisition cost. However, a precise costing requires better knowledge of the incidence and consequences of anaphylactic or anaphylactoid reactions to succinylcholine. IMPLICATIONS: The true cost of succinylcholine is more than 20 times the acquisition cost of the drug. The estimated cost is very sensitive to the risk and cost of patients dying or sustaining brain injury from anaphylactic or anaphylactoid reactions to succinylcholine.

How much are patients willing to pay to avoid postoperative nausea and vomiting?

Postoperative nausea and vomiting (PONV) are unpleasant experiences. However, there is no drug that is completely effective in preventing PONV. Whereas cost effectiveness analyses rely on specific health outcomes (e.g., years of life saved), cost-benefit analyses assess the cost and benefit of medical therapy in terms of dollars. We hypothesized that patients were willing to pay for a hypothetical new drug that would eliminate PONV. Eighty elective day surgical patients using general anesthesia participated in the study. After their recovery in the postanesthetic care unit, they were asked to complete an interactive computer questionnaire on demographics, the value of avoiding PONV, and their willingness to pay for an antiemetic. Patients were willing to pay US$56 (US$26--US$97; median, 25%--75%) for an antiemetic that would completely prevent PONV. Patients who developed nausea (n = 21; 26%) and vomiting (n = 9; 11%) were willing to pay US$73 (US$44--US$110) and $100 (US$61--US$200; median, 25%--75%), respectively (P < 0.05). Seventy-six percent of patients considered avoiding postoperative nausea and 78% of patients considered avoiding vomiting as important (> or = 50 mm on a 0--100-mm visual analog scale). Nausea or vomiting in the postanesthetic care unit, greater patient income, previous history of PONV, more importance placed on avoiding nausea and vomiting, increasing age, and being married are independent covariates that increase the willingness to pay estimates. Patients associated a value with the avoidance of PONV and were willing to pay between US$56 and US$100 for a completely effective antiemetic.

The business of perioperative medicine.

Medical centers should insist that their top officials have a firm grasp of contemporary business principles, use that skill set, and run the medical business like any other. This business imperative does not exclude a conscious decision to measure success by the amount of articles published or charity care given rather than the amount of profits. Physician leaders should insist that while they care for patients, someone cares for the business.

Using Medicare multiples results in disproportionate reimbursement for anesthesiologists compared to other physicians.

Multispecialty groups and insurer fee schedules computed as a multiple of the Medicare reimbursement rate have resulted in a severely low reimbursement rate for anesthesia compared to other specialties. The authors suggest that anesthesiologists negotiate for a discount from the usual and customary fee equal to what the other specialties have been asked to bear.

Myocardial ischemia correlates with reduced fibrinolytic activity following peripheral vascular surgery.

STUDY OBJECTIVES: To evaluate the relationship between perioperative ischemia and serial concentrations of D-dimer, which is a sensitive and specific marker of fibrinolytic activity. Myocardial ischemia and infarction are well-recognized complications of peripheral vascular surgery. We hypothesized that patients at increased risk of perioperative myocardial ischemia might be identified preoperatively by abnormal hemostatic indices. DESIGN: Prospective clinical outcomes study. SETTING: A 1,124-bed tertiary care medical center. PATIENTS: 42 ASA physical status II, III, and IV patients undergoing peripheral vascular surgery. INTERVENTIONS: Serial D-dimer concentrations were measured preoperatively, and at 24 and 72 hours postoperatively. Continuous 12-lead ST-segment monitoring (Mortara Instrument, Inc., Milwaukee, WI) was performed with the acquisition of a 12-lead ECG every 20 seconds for 72 hours. MEASUREMENTS AND MAIN RESULTS: D-dimer measurements were performed in duplicate using the Dimer Gold assay (American Diagnostica, Greenwich CT). Ischemic episodes, as defined by continuous 12-lead ST-segment monitoring, occurred in 49% of patients. There were no demographic differences between ischemic and nonischemic groups. Although baseline D-dimer concentrations were not statistically significantly different between groups, patients experiencing perioperative myocardial ischemia generated significantly less D-dimer during the perioperative period (p = 0. 014). CONCLUSIONS: PATIENTS with an impaired fibrinolytic response, as defined by reduced generation of D-dimer, experienced an increased incidence of perioperative myocardial ischemia.

Cost-effectiveness of prophylactic antiemetic therapy with ondansetron, droperidol, or placebo.

BACKGROUND: In an era of growing economic constraints on healthcare delivery, anesthesiologists are increasingly expected to understand cost analysis and evaluate clinical practices. Postoperative nausea and vomiting (PONV) are distressing for patients and may increase costs in an ambulatory surgical unit. The authors compared the cost-effectiveness of four prophylactic intravenous regimens for PONV: 4 mg ondansetron, 0.625 mg droperidol, 1.25 mg droperidol, and placebo. METHODS: Adult surgical outpatients at high risk for PONV were studied. Study drugs were administered intravenously within 20 min of induction of nitrous oxide-isoflurane or enflurane anesthesia. A decision-tree analysis was used to group patients into 12 mutually exclusive subgroups based on treatment and outcome. Costs were calculated for the prevention and treatment of PONV. Cost-effectiveness analysis was performed for each group. RESULTS: Two thousand sixty-one patients were enrolled. Efficacy data for study drugs have been previously reported, and the database from that study was used for pharmacoeconomic analysis. The mean-median total cost per patient who received prophylactic treatment with 4 mg ondansetron, 0.625 mg droperidol, 1.25 mg droperidol, and placebo were $112 or $16.44, $109 or $0.63, $104 or $0.51, and $164 or $51.20, respectively (P = 0.001, active treatment groups vs. placebo). The use of a prophylactic antiemetic agent significantly increased patient satisfaction (P < 0.05). Personnel costs in managing PONV and unexpected hospital admission constitute major cost components in our analysis. Exclusion of nursing labor costs from the calculation did not alter the overall conclusions regarding the relative costs of antiemetic therapy. CONCLUSION: The use of prophylactic antiemetic therapy in high-risk ambulatory surgical patients was more effective in preventing PONV and achieved greater patient satisfaction at a lower cost compared with placebo. The use of 1.25 mg droperidol intravenously was associated with greater effectiveness, lower costs, and similar patient satisfaction compared with 0.625 mg droperidol intravenously and 4 mg ondansetron intravenously.

How much labor is in a labor epidural? Manpower cost and reimbursement for an obstetric analgesia service in a teaching institution.

BACKGROUND: Some anesthesiologists avoid provision of obstetric analgesia services (OAS) because of low reimbursement rates for the work involved. This study defines the manpower costs of operating an OAS in a tertiary referral center and examines reimbursement for this cost. METHODS: The time spent providing OAS in a total of 55 parturients was studied prospectively using a modification of classic time and motion studies. RESULTS: Mean duration of OAS in our population was 412 +/- 313 min. Mean bedside anesthesia staff time was 90 +/- 40 min, and mean number of visits to each patient's bedside was 6.3 +/- 2.0 visits. Assuming staffing on demand for service (intermittent staffing), a minimum of 2.5 full-time equivalent (FTE) attending anesthesiologists was required to meet demand. With intermittent staffing, labor cost was $325 per patient. Actual practice at Duke University Medical Center is around-the-clock (dedicated) staffing, which requires 4.4 FTEs at a cost of $728 per patient. Neither average indemnity reimbursement ($299) nor Medicaid reimbursement ($204) covered the cost per OAS patient. Breaking even is possible under indemnity reimbursement because operating room reimbursement subsidizes OAS costs. Breaking even cannot occur with Medicaid reimbursement under any circumstances. CONCLUSIONS: Obstetric analgesia services requires a minimum of 2.5 FTE attending anesthesiologists at Duke University Medical Center. With the current payer mix, positive-margin operating room activities associated with the obstetric service are not sufficient to compensate for the losses incurred by an OAS. Around-the-clock dedicated obstetric staffing (4.4 FTEs) cannot operate profitably under any reasonable circumstances at our institution.

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.

UNLABELLED: Determining the appropriate amount of block time to allocate to surgeons and selecting the days on which to schedule elective cases can maximize operating room (OR) use. We used computer simulation to model OR scheduling. Inputs in the computer model included different methods to determine when a patient will have surgery (on-line bin-packing algorithms), case durations, lengths of time patients wait for surgery (2 wk is the median longest length of time that the outpatients [n = 367] surveyed considered acceptable), hours of block time each day, and number of blocks each week. For block time to be allocated to maximize OR utilization, two parameters must be specified: the method used to decide on what day a patient will have surgery and the average length of time patients wait to have surgery. OR utilization depends greatly on, and increases as, the average length of time patients wait for surgery increases. IMPLICATIONS: Operating room utilization can be maximized by allocating block time for the elective cases based on expected total hours of elective cases, scheduling patients into the first available date provided open block time is available within 4 wk, and otherwise scheduling patients in "overflow" time outside of the block time.

Statistical method to evaluate management strategies to decrease variability in operating room utilization: application of linear statistical modeling and Monte Carlo simulation to operating room management.

BACKGROUND: Operating room (OR) managers seeking to maximize labor productivity in their OR suite may attempt to reduce day-today variability in hours of OR time for which there are staff but for which there are no cases ("underutilized time"). The authors developed a method to analyze data from surgical services information systems to evaluate which management interventions can most effectively decrease variability in underutilized time. METHODS: The method uses seven summary statistics of daily workload in a surgical suite: daily allocated hours of OR time, estimated hours of elective cases, actual hours of elective cases, estimated hours of add-on cases, actual hours of add-on cases, hours of turnover time, and hours of underutilized time. Simultaneous linear statistical equations (a structural equation model) specify the relationship among these variables. Estimated coefficients are used in Monte Carlo simulations. RESULTS: The authors applied the analysis they developed to two OR suites: a tertiary care hospital's suite and an ambulatory surgery center. At both suites, the most effective strategy to decrease variability in underutilized OR time was to choose optimally the day on which to do each elective case so as to best fill the allocated hours. Eliminating all (1) errors in predicting how long elective or add-on cases would last, (2) variability in turnover or delays between cases, or (3) day-to-day variation in hours of add-on cases would have a small effect. CONCLUSIONS: This method can be used for decision support to determine how to decrease variability in underutilized OR time.

Computer simulation to determine how rapid anesthetic recovery protocols to decrease the time for emergence or increase the phase I postanesthesia care unit bypass rate affect staffing of an ambulatory surgery center.

UNLABELLED: Ambulatory surgery centers (ASC) are implementing new anesthetic techniques and rapid recovery protocols in the postanesthesia care unit (PACU) to achieve earlier discharge after general anesthesia. Using computer simulation, we addressed two questions. First, what is the decrease in an ASC's operating room (OR) staff if the time from which the surgery is finished to the time the patient leaves the OR is decreased? Second, what is the decrease in PACU nursing staffing if patients bypass phase I PACU (i.e., proceed from the OR directly to the phase II PACU)? The decrease in labor costs from rapid emergence or fast-tracking depends on how staff are compensated, how many ORs routinely run concurrently, and what percentage of patients undergo general anesthesia. The results show potential decreases in ASCs' labor costs ($7.39 per case) from technologies (e.g., new anesthetics or Bispectral Index [Aspect Medical Systems, Natick, MA] monitoring) to decrease emergence times or increase the phase I bypass rates. IMPLICATIONS: Decreases in operating room and postanesthesia care unit labor costs resulting from faster emergence and phase I postanesthesia care unit bypass vary depending on the amount of routine overtime, how the staff are compensated, and how many patients are routinely anesthetized each day.

Relying solely on historical surgical times to estimate accurately future surgical times is unlikely to reduce the average length of time cases finish late.

STUDY OBJECTIVE: To determine whether using only previous cases' surgical times for predicting accurately surgical times of future cases is likely to reduce the average length of time cases finish late (after their scheduled finish times). DESIGN: Computer simulation. MEASUREMENTS AND MAIN RESULTS: Data from an operating room (OR) information system for two surgical suites were analyzed. For each case performed in fiscal year 1996, we searched backward for 1 year and counted the number of previous cases that were the same type of procedure performed by the same surgeon. Then, for each suite, surgical times were fitted to a statistical model estimating the effect of the type of procedure and who the surgeon was on surgical time. The estimated "variance components" were used in Monte-Carlo computer simulations to evaluate whether a hypothetical increase in the number of previous cases available to estimate the next case's surgical time would improve scheduling accuracy. Predictions of how long newly scheduled cases should take were impaired because 36.5% +/- 0.4% (mean +/- SE) of cases at a tertiary surgical suite and 28.6% +/- 0.7% of cases at an ambulatory surgery center did not have any cases in the previous year with the same procedure type and surgeon. Computer simulation was used to generate additional hypothetical cases. Using this data, even having many previous cases on which to base predictions of future surgical times would only decrease the average length of time that cases finish late by a few minutes. CONCLUSION: An OR manager considering using only historical surgical times to estimate future surgical times should first investigate, using data from their own surgical suite, what percentage of cases do not have historical data. Even if there are sufficient historical data to estimate future surgical times accurately, relying solely on historical times is probably an ineffective strategy to have future cases finish on time.