Faculty Bibliography

OBJECTIVE:The aim of this study was to determine whether exposure to data from a risk calculator influences surgeons' assessments of risk and in turn, their decisions to operate. BACKGROUND:Little is known about how risk calculators inform clinical judgment and decision-making. METHODS:We asked a national sample of surgeons to assess the risks (probability of serious complications or death) and benefits (recovery) of operative and nonoperative management and to rate their likelihood of recommending an operation (5-point scale) for 4 detailed clinical vignettes wherein the best treatment strategy was uncertain. Surgeons were randomized to the clinical vignettes alone (control group; n = 384) or supplemented by data from a risk calculator (risk calculator group; n = 395). We compared surgeons' judgments and decisions between the groups. RESULTS:Surgeons exposed to the risk calculator judged levels of operative risk that more closely approximated the risk calculator value (RCV) compared with surgeons in the control group [mesenteric ischemia: 43.7% vs 64.6%, P < 0.001 (RCV = 25%); gastrointestinal bleed: 47.7% vs 53.4%, P < 0.001 (RCV = 38%); small bowel obstruction: 13.6% vs 17.5%, P < 0.001 (RCV = 14%); appendicitis: 13.4% vs 24.4%, P < 0.001 (RCV = 5%)]. Surgeons exposed to the risk calculator also varied less in their assessment of operative risk (standard deviations: mesenteric ischemia 20.2% vs 23.2%, P = 0.01; gastrointestinal bleed 17.4% vs 24.1%, P < 0.001; small bowel obstruction 10.6% vs 14.9%, P < 0.001; appendicitis 15.2% vs 21.8%, P < 0.001). However, averaged across the 4 vignettes, the 2 groups did not differ in their reported likelihood of recommending an operation (mean 3.7 vs 3.7, P = 0.76). CONCLUSIONS:Exposure to risk calculator data leads to less varied and more accurate judgments of operative risk among surgeons, and thus may help inform discussions of treatment options between surgeons and patients. Interestingly, it did not alter their reported likelihood of recommending an operation.

OBJECTIVE:To determine how surgeons' perceptions of treatment risks and benefits influence their decisions to operate. BACKGROUND:Little is known about what makes one surgeon choose to operate on a patient and another chooses not to operate. METHODS:Using an online study, we presented a national sample of surgeons (N = 767) with four detailed clinical vignettes (mesenteric ischemia, gastrointestinal bleed, bowel obstruction, appendicitis) where the best treatment option was uncertain and asked them to: (1) judge the risks (probability of serious complications) and benefits (probability of recovery) for operative and nonoperative management and (2) decide whether or not they would recommend an operation. RESULTS:Across all clinical vignettes, surgeons varied markedly in both their assessments of the risks and benefits of operative and nonoperative management (narrowest range 4%-100% for all four predictions across vignettes) and in their decisions to operate (49%-85%). Surgeons were less likely to operate as their perceptions of operative risk increased [absolute difference (AD) = -29.6% from 1.0 standard deviation below to 1.0 standard deviation above mean (95% confidence interval, CI: -31.6, -23.8)] and their perceptions of nonoperative benefit increased [AD = -32.6% (95% CI: -32.8,--28.9)]. Surgeons were more likely to operate as their perceptions of operative benefit increased [AD = 18.7% (95% CI: 12.6, 21.5)] and their perceptions of nonoperative risk increased [AD = 32.7% (95% CI: 28.7, 34.0)]. Differences in risk/benefit perceptions explained 39% of the observed variation in decisions to operate across the four vignettes. CONCLUSIONS:Given the same clinical scenarios, surgeons' perceptions of treatment risks and benefits vary and are highly predictive of their decisions to operate.

PURPOSE/OBJECTIVE:Given the well-established relationship between surgical volume and outcomes for many surgical procedures, we examined whether the same relationship exists for gastroschisis closure. METHODS:We conducted a retrospective analysis of infants who underwent gastroschisis closure between 1999 and 2007 using a California birth-linked cohort. Hospitals were divided into terciles based on the number of gastroschisis closures performed annually. Using regression techniques, we examined the effects of hospital volume on patient mortality and length of stay while controlling for patient and hospital confounders. RESULTS:We identified 1537 infants who underwent gastroschisis repair at 55 hospitals, 4 of which were high-volume and 42 of which were low-volume. The overall in-hospital mortality rate was 4.8% and the median length of stay was 46.5days. After controlling for other factors, patients treated at high-volume hospitals had significantly lower odds of inpatient mortality (OR 0.40; 95% CI 0.21, 0.76). There was a near-significant trend towards shorter hospital length of stay at highvolume hospitals (p=0.066). CONCLUSIONS:Patients who undergo gastroschisis closure at high-volume hospitals in California experience lower odds of in-hospital mortality compared to those treated at low-volume hospitals. These findings offer initial evidence to support policies that limit the number of hospitals providing complex newborn surgical care.

BACKGROUND:Long-term survival (LTS) is uncommon for patients with pancreatic ductal adenocarcinoma (PDAC). We sought to identify factors that predict 10-year, LTS after resection of PDAC. METHODS:We identified all patients with PDAC who underwent resection at UCLA after 1990 and included all patients eligible for observed LTS (1/1/1990-12/31/2004). An independent pathologist reconfirmed the diagnosis of PDAC in patients with LTS. Logistic regression was used to predict LTS on the basis of patient and tumor characteristics. RESULTS:Of 173 included patients, 53% were male, median age at diagnosis was 66 years, and median survival was 23 months. The rate of observed LTS was 12.1% (n = 21). Age, sex, number of lymph nodes evaluated, margin status, lymphovascular invasion, and adjuvant chemotherapy and radiation were not associated with LTS. The following were associated with LTS on bivariate analysis: low AJCC stage (Ia, Ib, IIa) (P = .034), negative lymph node status (P = .034), low grade (well-, moderately-differentiated) (P = .001), and absence of perineural invasion (P = .019). Only low grade (odds ratio 7.17, P = .012) and absent perineural invasion (odds ratio 3.28, P = .036) were independently associated with increased odds of LTS. Our multivariate model demonstrated good discriminatory power for LTS, as indicated by a c-statistic of 0.7856. CONCLUSION:Absence of perineural invasion and low tumor grade were associated with greater likelihood of LTS. Understanding the tumor biology of LTS may provide critical insight into a disease that is typically marked by aggressive behavior and limited survival.

BACKGROUND:Little is known about hospital use of postacute care after surgery and whether it is related to measures of surgical quality. RESEARCH DESIGN/METHODS:We used data merged between a national surgery registry, Medicare inpatient claims, the Area Resource File, and the American Hospital Association Annual Survey (2005-2008). Using bivariate and multivariate analyses, we calculated hospital-level, risk-adjusted rates of postacute care use for both inpatient facilities (IF) and home health care (HHC), and examined the association of these rates with hospital quality measures, including mortality, complications, readmissions, and length of stay. RESULTS:Of 112,620 patients treated at 217 hospitals, 18.6% were discharged to an IF, and 19.9% were discharged with HHC. Even after adjusting for differences in patient and hospital characteristics, hospitals varied widely in their use of both IF (mean, 20.3%; range, 2.7%-39.7%) and HHC (mean, 22.3%; range, 3.1%-57.8%). A hospital's risk-adjusted postoperative mortality rate or complication rate was not significantly associated with its use of postacute care, but higher 30-day readmission rates were associated with higher use of IF (24.1% vs. 21.2%, P=0.03). Hospitals with longer average length of stay used IF less frequently (19.4% vs. 24.4%, P<0.01). CONCLUSIONS:Hospitals vary widely in their use of postacute care. Although hospital use of postacute care was not associated with risk-adjusted complication or mortality rates, hospitals with high readmission rates and shorter lengths of stay used inpatient postacute care more frequently. To reduce variations in care, better criteria are needed to identify which patients benefit most from these services.

OBJECTIVE:To examine the validity of hybrid quality measures that use both clinical registry and administrative claims data, capitalizing on the strengths of each data source. BACKGROUND:Previous studies demonstrate substantial disagreement between clinical registry and administrative claims data on the occurrence of postoperative complications. Clinical data have greater validity than claims data for quality measurement but can be burdensome for hospitals to collect. METHODS:American College of Surgeons National Surgical Quality Improvement Program records were linked to Medicare inpatient claims (2005-2008). National Quality Forum-endorsed risk-adjusted measures of 30-day postoperative complications or death assessed hospital quality for patients undergoing colectomy, lower extremity bypass, or all surgical procedures. Measures use hierarchical multivariable logistic regression to identify statistical outliers. Measures were applied using clinical data, claims data, or a hybrid of both data sources. Kappa statistics assessed agreement on determinations of hospital quality. RESULTS:A total of 111,984 patients participated from 206 hospitals. Agreement on hospital quality between clinical and claims data was poor. Hybrid models using claims data to risk-adjust complications identified by clinical data had moderate agreement with all clinical data models, whereas hybrid models using clinical data to risk-adjust complications identified by claims data had routinely poor agreement with all clinical data models. CONCLUSIONS:Assessments of hospital quality differ substantially when using clinical registry versus administrative claims data. A hybrid approach using claims data for risk adjustment and clinical data for complications may be a valid alternative with lower data collection burden. For quality measures focused on postoperative complications to be meaningful, such policies should require, at a minimum, collection of clinical outcomes data.

BACKGROUND:As surgery becomes incorporated into global health programs, it will be critical for clinicians to take into account already existing surgical care systems within low-income countries. To inform future efforts to expand the local system and systems in comparable regions of the developing world, we aimed to describe current patterns of surgical care at a major urban teaching hospital in Mozambique. METHODS:We performed a retrospective review of all general surgery patients treated between August 2012 and August 2013 at the Hospital Central Maputo in Maputo, Mozambique. We reviewed emergency and elective surgical logbooks, inpatient discharge records, and death records to report case volume, disease etiology, and mortality. RESULTS:There were 1598 operations (910 emergency and 688 elective) and 2606 patient discharges during our study period. The most common emergent surgeries were for nontrauma laparotomy (22%) followed by all trauma procedures (18%), whereas the most common elective surgery was hernia repair (31%). The majority of lower extremity amputations were above knee (69%). The most common diagnostic categories for inpatients were infectious (31%), trauma (18%), hernia (12%), neoplasm (10%), and appendicitis (5%). The mortality rate was 5.6% (146 deaths), approximately half of which were related to sepsis. CONCLUSIONS:Our data demonstrate the general surgery caseload of a large, academic, urban training and referral center in Mozambique. We describe resource limitations that impact operative capacity, trauma care, and management of amputations and cancer. These findings highlight challenges that are applicable to a broad range of global surgery efforts.

In-hospital cardiopulmonary arrest can contribute significantly to publicly reported mortality rates. Systems to improve mortality are being implemented across all specialties. A review was conducted for all surgical patients >18 years of age who experienced a "Code Blue" event between January 1, 2013 and March 9, 2014 at a university hospital. A previously validated Modified Early Warning Score (MEWS) using routine vital signs and neurologic status was calculated at regular intervals preceding the event. In 62 patients, the most common causes of arrest included respiratory failure, arrhythmia, sepsis, hemorrhage, and airway obstruction, but remained unknown in 27 per cent of cases. A total of 56.5 per cent of patients died before hospital discharge. In-hospital death was associated with American Society of Anesthesiologists status (P = 0.039) and acute versus elective admission (P = 0.003). Increasing MEWS on admission, 24 hours before the event, the event-day, and a maximum MEWS score on the day of the event increased the odds of death. Max MEWS remained associated with death after multivariate analysis (odds ratio 1.39, P = 0.025). Simple and easy to implement warning scores such as MEWS can identify surgical patients at risk of death after arrest. Such recognition may provide an opportunity for clinical intervention resulting in improved patient outcomes and hospital mortality rates.