Faculty Bibliography

INTRODUCTION/BACKGROUND:Autonomy during residency is crucial to the training and development of competent surgeons. An essential component of this process is the 'teaching assistant (TA)' case, an indispensable opportunity for residents to gain confidence and hone intraoperative skills. However, high-quality data on the volume and diversity of cases that graduates perform are scarce. METHODS:A retrospective analysis was performed from publicly collected data of operative case logs from general surgery residents graduating from ACGME-accredited programs from 2006 to 2023. Data on the median overall number of surgeon chief and TA cases were retrieved. Collected data were organized based on sub-specialties. The Mann-Kendall trend test was used to investigate trends in TA cases and surgeon chief operative volume. RESULTS:Between 2007 and 2023, the surgeon chief cases gradually increased from 229 to 274 (19.6 ​% increase; τ ​= ​0.610, p ​= ​0.001). There was a concurrent 72.7 ​% increase in TA cases from a median of 22-38 (τ ​= ​0.574, p ​= ​0.001). Surgeon chief (283 per resident) and TA cases (43 per resident) peaked in 2018-2019 and 2016-2017. The uptrend in TA cases was associated with the significant increase in colorectal (τ ​= ​0.559, p ​= ​0.001), general surgery-other (τ ​= ​0.404, p ​= ​0.018), and hepatopancreaticobiliary (HPB) (τ ​= ​0.596, p ​= ​0.001) subspecialties. Trauma and vascular surgery did not change significantly. With respect to total chief cases, general surgery-other (τ ​= ​0.956, p=<0.001), HPB (τ ​= ​0.713, p=<0.001) and colorectal (τ ​= ​0.522, p ​= ​0.004) volume increased. There was no significant change in trauma and foregut volume, while the volume of endocrine (τ ​= ​-0.485, p ​= ​0.006) and vascular surgery (τ ​= ​0.603, p ​= ​0.001) dropped significantly. The procedural category with the highest chief and TA volume was 'colorectal tract - large intestine.' Most procedural categories (53.49 ​%) retained a median of 0 teaching cases. No chief cases were logged for the specialties generally not considered part of general surgery (genitourinary, nervous system, orthopedics, and gynecology), although a median of 1 surgeon chief genitourinary case was recorded from 2018 to 2023. CONCLUSIONS:Over the past seventeen years, there has been a gradual uptrend in the number of surgeon chief and TA cases. While this is a positive indicator of improved autonomy, further research must focus on strategies to improve resident autonomy to train well-rounded surgeons safely.

OBJECTIVES/OBJECTIVE:Numerous animal and epidemiologic studies have demonstrated a positive association between maternal obesity in pregnancy and obesity in offspring. The biologic mechanisms of this association remain under investigation. One proposed mechanism includes fetoplacental endothelial dysfunction secondary to inflammation. Endocan is a relatively new biomarker for endothelial dysfunction and inflammation. Our objectives were to examine (1) the association between maternal obesity and neonatal serum endocan at birth, and (2) the association between neonatal serum endocan at birth and pediatric obesity at 24-36 months of age. STUDY DESIGN/METHODS:This was a secondary analysis of a prospective cohort of neonates born < 33 weeks gestation. Serum endocan was collected within 48 hours of birth. Serum endocan levels were compared in neonates born to obese mothers vs. those born to non-obese mothers. BMI data were retrospectively collected from cohort neonates between 24 and 36 months of age. RESULTS:The analysis included 120 mother/neonate dyads. Neonates born to obese mothers had higher median serum endocan at birth compared to neonates born to non-obese mothers (299 ng/L [205-586] vs. 251 ng/L [164-339], p = 0.045). In a linear regression modeled on neonatal serum endocan level, maternal obesity had a statistically significant positive association (p = 0.021). Higher mean serum endocan level at birth was associated with pediatric obesity between 24 and 36 months (obese vs. non-obese offspring; 574 ng/L (222) vs. 321 ng/L (166), p = 0.005). CONCLUSIONS:In our cohort of preterm neonates, elevated serum endocan at birth was associated with both maternal obesity and downstream pediatric obesity. More research is needed to understand intergenerational transmission of obesity. A large focus has been on epigenetic modification. Endothelial dysfunction and inflammation may play important roles in these pathways. Effective biomarkers, including endocan, may also serve as intermediate outcomes in future pregnancy research.

Background: The specific etiology of spontaneous intestinal perforation (SIP) and necrotizing enterocolitis (NEC) remains elusive. Both can present acutely without antecedent signs and can be difficult to differentiate. Neonatal nucleated red blood cell (NRBC) counts are part of the routine admission and serial CBCs drawn on premature neonates. Elevated NRBC counts could represent relative intrauterine hypoxemia, a possible risk factor for the development of SIP or NEC. Methods: We compared premature neonates with SIP to premature neonates with NEC and controls, matched gestational age (GA) and birth weight (BW). Kruskal-Wallis, Chi-Square, or Fisher's exact tests and univariate and multivariate nominal logistic regression models were used to estimate the association of baseline NRBC. Median times to SIP and NEC were calculated using the Kaplan-Meier method. All analyses were performed with SAS 9.4. Results: Male sex (72.5%), lower GA [Median (Q1, Q3): 25.1 (23.8, 28)], and lower BW [Median (Q1, Q3): 690 g (585, 1072)] had the highest incidence of SIP compared to NEC or controls. Increased baseline NRBC was associated with lower odds of developing NEC compared to controls [Median (Q1, Q3): 9 (5, 29) vs 19 (10, 51); OR (CI) 0.70 (0.55, 0.89), p-value = 0.0033]. Increased baseline NRBC was associated with higher odds of developing SIP compared to NEC [Median (Q1, Q3): 9 (5, 29) vs 19 (10, 51); OR (CI) 1.61 (1.18, 2.20) p-value = 0.0027]. There were no significant differences between intrauterine growth restriction (IUGR), maternal hypertension, chorioamnionitis, multiple births, or depressed APGAR scores in all three groups. NRBC for SIP neonates remained significantly higher at the day of life (DOL) 1-3 compared to other groups [Median (Q1, Q3): 23 (6, 93), p-value = 0.0020]. The percentage of patients with NRBC >4, remained elevated for patients with SIP as late as week three (p = 0.0023). Conclusion: ELBW, male sex, and elevated baseline NRBC were significantly associated with the risk of developing SIP compared to NEC or controls. NRBC remained significantly elevated on DOL 1-3, compared to NEC or controls. Between the groups, there were no significant differences in perinatal stressors.

BACKGROUND:There is a lack of understanding of the scope and purpose of teaching assistant cases, impact on patients and safety, as well as the facilitators or barriers to resident participation in these cases. METHODS:Four databases (PubMed, Embase, Web of Science, and the Education Resources Information Center), were searched. The references of identified resources were additionally hand-searched. 10 articles were identified and considered in the literature review. RESULTS:The TA case literature focuses on case numbers and safety. The discussions of papers allude to perceived benefits of TA cases. The literature review reveals that residents are more likely to be granted TA opportunities if they show themselves worthy of entrustment. CONCLUSIONS:The work elucidates aspects of TA cases that have not previously been emphasized or highlighted. The literature review can serve to inform attending surgeons and trainees how to optimize the opportunities teaching assistant cases can afford.

BACKGROUND:The correlation between procoagulant levels-factor VIII (FVIII), von Willebrand factor (vWF), and fibrinogen-and risk of thrombosis has been well documented in adult populations. We hypothesize that interaction of passively transferred isoagglutinins in premature neonates with a compromised immune system may trigger an immune response that can target the immature gastrointestinal tract. The objective of this study is to evaluate if there are procoagulant level differences in preterm newborns stratified by ABO blood group. METHODS:VWF, FVIII, and fibrinogen levels were analyzed in neonates ≤32 weeks and/or birthweight ≤1500 g over the first 6 weeks of life. Demographic, blood type, and transfusion data were collected. RESULTS:Elevations in vWF and FVIII were found to be statistically significant in the third week of life in non-O neonates vs. type O neonates. FVIII was also found to be significantly elevated in week 1. Transfused neonates also showed elevations between weeks 0 and 3. CONCLUSION:There appears to be a time-dependent variation in procoagulant factor levels in preterm newborns. Although the clinical significance remains unclear, prothrombotic factors vWF and FVIII are significantly higher in non-O blood-type preterm neonates in the third week of life.

PURPOSE/OBJECTIVE:Despite significant radiation exposure involved with computed tomography (CT) in evaluation of pediatric appendicitis, its use is still widespread. The goal of this study was to assess the effect of a staged imaging pathway for appendicitis to significantly decrease CT use while maintaining diagnostic accuracy. METHODS:Chart review was performed for patients evaluated for appendicitis over a 12-month period prior to and after pathway implementation. RESULTS:There was a significant decrease in CT use as initial imaging after implementation of the pathway; 87.1-13.4 % for evaluations positive for appendicitis (decrease 84.6 %, p < 0.0001) and 82.6-9.2 % for evaluations negative for appendicitis (decrease 88.9 %, p < 0.0001). Use of CT during any point in the evaluation decreased from 91.7 to 25.1 % (decrease 72.6 %, p < 0.0001). The negative appendectomy rate was similar; 5.4 % prior, 4.9 % post (p = 0.955). The missed appendicitis rate did not statistically change; 1.1 % prior, 3.7 % post (p = 0.523). The perforation rate was not statistically altered; 6.5 % prior; 9.8 % post (p = 0.421). 350 less patients underwent CT during the year following the pathway. CONCLUSIONS:The staged imaging pathway resulted in a marked decrease in children exposed to CT without compromising diagnostic accuracy.

BACKGROUND:Necrotizing enterocolitis (NEC) affects up to 10% of extremely-low-birthweight infants, with a 30% mortality rate. Currently, no biomarker reliably facilitates early diagnosis. Since thrombocytopenia and bowel ischemia are consistent findings in advanced NEC, we prospectively investigated two potential biomarkers: reticulated platelets (RP) and intestinal alkaline phosphatase (iAP). METHODS:Infants born ≤ 32 weeks and/or ≤ 1500 g were prospectively enrolled from 2009 to 2012. Starting within 72 hours of birth, 5 weekly whole blood specimens were collected to measure RP and serum iAP. Additional specimens were obtained at NEC onset (Bell stage II or III) and 24 hours later. Dichotomous cut-points were calculated for both biomarkers. Non-parametric (Mann-Whitney) and Chi-square tests were used to test differences between groups. Differences in Kaplan-Meier curves were examined by log-rank test. The Cox proportional hazards model estimated hazard ratios. RESULTS:A total of 177 infants were enrolled in the study, 15 (8.5%) of which developed NEC (40% required surgery and 20% died). 14 (93%) NEC infants had "low" (≤ 2.3%) reticulated platelets, and 9 (60%) had "high" iAP (>0 U/L) in at least one sample before onset. Infants with "low" RP were significantly more likely to develop NEC [HR=11.0 (1.4-83); P=0.02]. Infants with "high" iAP were at increased risk for NEC, although not significant [HR=5.2 (0.7-42); P=0.12]. Median iAP levels were significantly higher at week 4 preceding the average time to NEC onset by one week (35.7 ± 17.3 days; P=0.02). CONCLUSION/CONCLUSIONS:Decreased RP serves as a sensitive marker for NEC onset, thereby enabling early preventative strategies. iAP overexpression may signal NEC development.

Wandering spleen with torsion, a rare clinical diagnosis, was found to be the cause of chronic abdominal pain in an 11-year-old female with a history of congenital diaphragmatic hernia repaired at three days of age. Doppler ultrasound revealed patent vessels with splenomegaly, and computed tomography (CT) showed an absence of the spleen in the left subphrenic space with torsion at the splenic hilum. Due to the chronicity of pain and risk of ischemia from torsion, open splenopexy with Vicryl mesh was performed. This case report/review of the literature discusses the rarity of this condition, and the importance of timely diagnosis and intervention.

Outcomes research in pediatric surgery can be defined as the analysis of pediatric surgical outcomes and their predictors at different levels in the health care delivery system. The objectives of this article are to understand the differences between outcomes research and clinical trials as well as to gain familiarity with public multispecialty and specialty-specific databases. The utility of outcomes research extends to benchmarking the quality of care, refinement of management strategies, patient education, and marketing. Assessment of the integration of a new surgical technique into the health care system is best determined by examining a population-based registry, whereas comparative efficacy of surgical procedures is best assessed by randomized clinical trials. In the first part of this 2-part series, an overview and brief outline of available resources for outcomes research in pediatric surgery are reviewed. In part 2, a template is presented on how to structure and design an outcomes research question.