Faculty Bibliography

BACKGROUND:For many surgical operations, there is a well-established relationship between surgical volume and outcome. We investigated whether this relationship exists for infants with gastroschisis. METHODS:Using the Kids' Inpatient Database for years 2003, 2006, 2009, and 2012, we identified all patients undergoing gastroschisis repair. Controlling for patient characteristics and complexity of disease (comorbid intestinal atresia/perforation, necrotizing enterocolitis, and respiratory distress syndrome), we compared surgical outcomes (mortality, length of stay, and incidence of TPN cholestasis) by hospital volume based on quartile for gastroschisis cases treated per year. RESULTS:We identified 7769 patients treated at 743 hospitals. The majority of hospitals were low-volume (n=445), while only 49 were high-volume. The overall mortality rate was 4.3%, and the median length of stay was 34days. Adjusting for clinical and demographic characteristics, patients treated at high-volume hospitals had similar rates of TPN cholestasis and similar mortality rates, but a higher chance for a prolonged length of stay compared to those treated at low-volume hospitals. CONCLUSIONS:Using national data, we found that gastroschisis patients treated at high-volume hospitals did not have improved outcomes. The benefits of high-volume hospitals, which seem to be important for complex pediatric surgery, may not apply to treatment of gastroschisis. LEVEL OF EVIDENCE/METHODS:Level III Retrospective Study.

BACKGROUND:Several studies have demonstrated the safety and short-term success of nonoperative management in children with acute, uncomplicated appendicitis. Nonoperative management spares the patients and their family the upfront cost and discomfort of surgery, but also risks recurrent appendicitis. METHODS:Using decision-tree software, we evaluated the cost-effectiveness of nonoperative management versus routine laparoscopic appendectomy. Model variables were abstracted from a review of the literature, Healthcare Cost and Utilization Project, and Medicare Physician Fee schedule. Model uncertainty was assessed using both one-way and probabilistic sensitivity analyses. We used a $100,000 per quality adjusted life year (QALY) threshold for cost-effectiveness. RESULTS:Operative management cost $11,119 and yielded 23.56 quality-adjusted life months (QALMs). Nonoperative management cost $2277 less than operative management, but yielded 0.03 fewer QALMs. The incremental cost-to-effectiveness ratio of routine laparoscopic appendectomy was $910,800 per QALY gained. This greatly exceeds the $100,000/QALY threshold and was not cost-effective. One-way sensitivity analysis found that operative management would become cost-effective if the 1-year recurrence rate of acute appendicitis exceeded 39.8%. Probabilistic sensitivity analysis indicated that nonoperative management was cost-effective in 92% of simulations. CONCLUSIONS:Based on our model, nonoperative management is more cost-effective than routine laparoscopic appendectomy for children with acute, uncomplicated appendicitis. LEVEL OF EVIDENCE/METHODS:Cost-Effectiveness Study: Level II.

BACKGROUND:Small studies done during the past decade have demonstrated same-day discharge after appendectomy as an option for non-perforated appendicitis. Here we have examined a large cohort to confirm that same-day discharge in acute non-perforated appendicitis is a safe option. STUDY DESIGN:This was a retrospective study of patients from 14 Southern California Region Kaiser Permanente medical centers. All patients older than 18 years of age with acute, non-perforated appendicitis who underwent a laparoscopic appendectomy between 2010 and 2014 were included. We compared patients discharged on the day of surgery with patients hospitalized for 1 night. We examined readmission rates, complication rates, postoperative emergency department visits, postoperative diagnostic or therapeutic radiology visits, reoperations, and cost of treatment. RESULTS:The cohort was composed of 12,703 patients; 6,710 patients were in the same-day discharge group and 5,993 patients were in the hospitalized group. Patients in the same-day discharge group had a lower rate of readmission within 30 days when compared with the hospitalized group (2.2% vs 3.1%; p < 0.005). In both groups, postoperative rates of visits to emergency or radiology department for diagnostic or therapeutic imaging studies were statistically similar. Postoperative general surgery department visits were slightly higher in the hospitalized group (85% vs 81%; p < 0.001). CONCLUSIONS:Adult patients with acute, non-perforated appendicitis can be discharged safely on the day of surgery without higher rates of postoperative complication or readmission rates compared with those hospitalized after surgery. In addition, same-day discharge in this patient group is cost-effective.

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.

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.

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.