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Objective: To develop accurate preoperative risk prediction models for multiple adverse postoperative outcomes applicable to a broad surgical population using a parsimonious common set of risk variables and outcomes. Summary Background Data: Currently, preoperative assessment of surgical risk is largely based on subjective clinician experience. We propose a paradigm shift from the current postoperative risk adjustment for cross-hospital comparison to patient-centered quantitative risk assessment during the preoperative evaluation. Methods: We identify the most common and important predictor variables of postoperative mortality, overall morbidity, and 6 complication clusters from previously published prediction analyses that used forward selection stepwise logistic regression. We then refit the prediction models using only the 8 most common and important predictor variables, and compare the discrimination and calibration of these models to the original full-variable models using the c-index, Hosmer-Lemeshow analysis, and Brier scores. Results: Accurate risk models for 30-day outcomes of mortality, overall morbidity, and 6 clusters of complications were developed using a set of 8 preoperative risk variables. C-indexes of the 8 variable models are between 97.9% and 99.2% of those of the full models containing up to 28 variables, indicating excellent discrimination using fewer predictor variables. Hosmer-Lemeshow analyses showed observed to expected event rates to be nearly identical between parsimonious models and full models, both showing good calibration. Conclusions: Accurate preoperative risk assessment of postoperative mortality, overall morbidity, and 6 complication clusters in a broad surgical population can be achieved with as few as 8 preoperative predictor variables, improving feasibility of routine preoperative risk assessment for surgical patients. [ABSTRACT FROM AUTHOR]

Objective: To develop parsimonious prediction models for postoperative mortality, overall morbidity, and 6 complication clusters applicable to a broad range of surgical operations in adult patients. Summary Background Data: Quantitative risk assessment tools are not routinely used for preoperative patient assessment, shared decision making, informed consent, and preoperative patient optimization, likely due in part to the burden of data collection and the complexity of incorporation into routine surgical practice. Methods: Multivariable forward selection stepwise logistic regression analyses were used to develop predictive models for 30-day mortality, overall morbidity, and 6 postoperative complication clusters, using 40 preoperative variables from 2,275,240 surgical cases in the American College of Surgeons National Surgical Quality Improvement Program data set, 2005 to 2012. For the mortality and overall morbidity outcomes, prediction models were compared with and without preoperative laboratory variables, and generic models (based on all of the data from 9 surgical specialties) were compared with specialty-specific models. In each model, the cumulative c-index was used to examine the contribution of each added predictor variable. C-indexes, Hosmer-Lemeshow analyses, and Brier scores were used to compare discrimination and calibration between models. Results: For the mortality and overall morbidity outcomes, the prediction models without the preoperative laboratory variables performed as well as the models with the laboratory variables, and the generic models performed as well as the specialty-specific models. The c-indexes were 0.938 for mortality, 0.810 for overall morbidity, and for the 6 complication clusters ranged from 0.757 for infectious to 0.897 for pulmonary complications. Across the 8 prediction models, the first 7 to 11 variables entered accounted for at least 99% of the c-index of the full model (using up to 28 nonlaboratory predictor variables). Conclusions: Our results suggest that it will be possible to develop parsimonious models to predict 8 important postoperative outcomes for a broad surgical population, without the need for surgeon specialty-specific models or inclusion of laboratory variables. [ABSTRACT FROM AUTHOR]

Background: Pancreatic ductal adenocarcinoma (PDAC) is characterized by an aggressive biology and poor prognosis. Experimental evidence has suggested a role for the transcriptional repressor Zinc finger E-box binding homeobox 1 (ZEB1) in epithelial-mesenchymal transition, invasion, and metastasis in PDAC. ZEB1 expression has been observed in cancer cells as well as stromal fibroblasts. Our study aimed to evaluate the prognostic value of ZEB1 expression in PDAC tissue. Methods: Patient baseline and follow-up data were extracted from a prospectively maintained database. After clinicopathologic re-review, serial sliced tissue slides were immunostained for ZEB1, E-cadherin, vimentin, and pan-cytokeratin. ZEB1 expression in cancer cells and adjacent stromal fibroblasts was graded separately and correlated to routine histopathologic parameters and survival after resection. Results: A total of 117 cases of PDAC were included in the study. High ZEB1 expression in cancer cells and in stromal cancer-associated fibroblasts was associated with poor prognosis. There was also a trend for poor prognosis with a lymph node ratio of greater than 0.10. In line with its role as an inducer of epithelial-mesenchymal transition, ZEB1 expression in cancer cells was positively correlated with Vimentin expression and negatively with E-Cadherin expression. In multivariate analysis, stromal ZEB1 expression grade was the only independent factor of survival after resection. Conclusion: Our data suggest that ZEB1 expression in cancer cells as well as in stromal fibroblasts are strong prognostic factors in PDAC. Stromal ZEB1 expression is identified for the first time as an independent predictor of survival after resection of PDAC. This observation suggests that therapies targeting ZEB1 and its downstream pathways could hit both cancer cells and supporting cancer-associated fibroblasts. [Copyright &y& Elsevier]

Abstract: Background/purpose: Children suffering from abusive head trauma (AHT) have worse outcomes compared to non-AHT, but the reasons for this are unclear. We hypothesized that delayed medical care associated with AHT causes prolonged pre-hospital hypotension and hypoxia as measured by admission base deficit (BD), and that this would correlate with outcome. Methods: We performed a 10-year retrospective chart review of children admitted for AHT at two academic level-I trauma centers. Statistics were performed using Student's t test, chi-square analysis, and multivariate logistic regression, and considered significant at p<0.05. Results: Four-hundred twelve children with AHT were identified, and admission BD was drawn for 148/412 (36%) children, including 104 survivors and 44 non-survivors. Non-survivors had significantly higher BD compared to survivors (12.6±1.6 versus 5.3±0.6, p<0.001). Non-survivors were more likely to be intubated pre-hospital and get cardiopulmonary resuscitation (CPR) (p<0.001). Mortality increased with rising BD, according to CPR status. There was no difference in patterns of brain injury between survivors and non-survivors (p>0.05). Conclusions: BD correlates with mortality in children suffering severe AHT. Non-survivors are also more likely to be intubated pre-hospital and require CPR, with no difference in pattern of brain injury, suggesting that secondary injury is a major determinant of outcome in severe AHT. [Copyright &y& Elsevier]

Background: It has been shown that crystalloid fluid-overload promotes anastomotic instability. As physiologic anastomotic healing requires the sequential infiltration of different cells, we hypothesized this to be altered by liberal fluid regimes and performed a histomorphological analysis. Methods: 36 Wistar rats were randomized into 4 groups (n=8-10 rats/group) and treated with either liberal (+) or restrictive (−) perioperative crystalline (Jonosteril® = Cry) or colloidal fluid (Voluven® = Col). Anastomotic samples were obtained on postoperative day 4, routinely stained and histophathologically reviewed. Anastomotic healing was assessed using a semiquantitative score, assessing inflammatory cells, anastomotic repair and collagenase activity. Results: Overall, the crystalloid overload group (Cry (+)) showed the worst healing score (P < 0.01). A substantial increase of lymphocytes and macrophages was found in this group compared to the other three (P < 0.01). Both groups that received colloidal fluid (Col (+) and Col (−)) as well as the group that received restricted crystalloid fluid resuscitation (Cry (−)) had better intestinal healing. Collagenase activity was significantly higher in the Cry (+) group. Conclusion: Intraoperative infusion of high-volume crystalloid fluid leads to a pathological anastomotic inflammatory response with a marked infiltration of leukocytes and macrophages resulting in accelerated collagenolysis. [Copyright &y& Elsevier]

Stroke remains a potentially devastating complication of aortic arch intervention. The value of neurophysiologic intraoperative monitoring (NIOM) in the early identification of stroke is unclear. We evaluated the utility of NIOM for early stroke detection in aortic arch surgery. Across 8 years at our institution, 365 patients underwent aortic arch surgery with hypothermic circulatory arrest, and 224 cases utilized NIOM. One patient was excluded for intraoperative death. In the remaining cohort, we reviewed the incidence, timing, and location of strokes, and the incidence and nature of NIOM alerts. Hemiarch was performed in 154 patients and total arch replacement in 69 patients. Stroke occurred in 6.3% of all cases (14 out of 223), 15.9% of total arches (11 out of 69), and 2.0% of hemiarches (3 out of 154). There were 33 NIOM alerts (14.8%), and 9 patients had both alerts and stroke. Of these, NIOM deficits plausibly correlated with imaging findings in 7 cases (78%). Of the 5 stroke patients without NIOM alerts, 2 developed neurologic symptoms 3 days or more postoperatively, and infarcts in 3 patients did not result in sensory or motor deficits. Excluding 2 patients with late stroke, the sensitivity of NIOM for stroke detection was 75%, specificity was 88.5%, positive predictive value was 27.3%, and negative predictive value was 97.4%. Despite a low positive predictive value requiring a high level of discrimination when interpreting abnormal findings, NIOM has high sensitivity and specificity for the early stroke detection. Furthermore, its high negative predictive valve is reassuring for low risk of stroke in the absence of alerts. Neuromonitoring during aortic arch surgery has high sensitivity and specificity for early detection of stroke, despite a low positive predictive value for permanent neurologic deficits, alerts can correspond to correctable intraoperative abnormalities as well as stroke. Intraoperative identification of neurologic deficits can lead to intraoperative interventions to reverse deficits, and earlier postprocedural neurologic imaging and catheter-based interventions if indicated. Furthermore, the high negative predictive value of neuromonitoring means that patients without neuromonitoring alerts are very unlikely to have a postoperative stroke. [Display omitted] [ABSTRACT FROM AUTHOR]

Burnout is prevalent among vascular surgery trainees. Here we aim to identify modifiable risk factors for burnout in vascular surgery training, to facilitate the development of programs to enhance and sustain trainee well-being. The Association of Program Directors in Vascular Surgery issued the Annual Training survey in the fall of 2018 to all trainees. The survey contained items to assess frequency of burnout, as well as mentorship, training environment, and stress coping mechanisms using an abbreviated COPE (Coping Orientation to Problems Experienced) inventory. Of 628 surveys issued, the response rate was 30% (n = 188). Respondents indicated that the majority of programs offer mentorship opportunities (n = 150 [83%]) that are longitudinal throughout the duration of training (n = 140 [77%]). Fifty-eight percent (n = 109) indicated there was an appropriate balance between learning and productivity in their program, with more respondents leaning toward too much clinical productivity (n = 57) and fewer toward too much learning (n = 19). Forty-five percent of respondents indicated feeling burnout at least weekly (n = 81). The burnout group was less likely to report an appropriate balance between clinical productivity and learning (49.4% vs 67.7%; P <.001), as well as a lower frequency of mentorship opportunities (72.1% vs 92.7%; P <.001). Certain coping skills were used more frequently in the burnout group, including self-distraction, disengagement, humor, self-blame, and substance use. In multivariate analysis, frequent use of self-blame conferred a 9.847-fold increased risk (95% confidence interval, 2.114-45.871) of burnout (P =.003), while feeling appropriately challenged by the faculty was significantly protective (odds ratio for burnout, 0.158; 95% confidence interval, 0.031-0.820; P =.03). The protective effect against vascular surgery trainee burnout conferred by the availability of mentorship suggests that an expansion and emphasis on mentorship in training may help to mitigate trainee burnout. Mentorship may also be a suitable channel to assess for an appropriate level of challenge, as well as for an appropriate balance between clinical productivity and learning that, when present, are also protective against burnout. Furthermore, the correlation between the frequent use of certain coping skills and burnout highlight this as an area for intervention, potentially through a combination of mentor modeling and formal training on healthy stress-related coping strategies. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Head injury secondary to abusive head trauma (AHT) is a major cause of morbidity and mortality in susceptible young infants and children. Diagnosing AHT remains challenging and is often complicated by a questionable mechanism of injury. Concern of ionizing radiation risk to children undergoing head CT imaging warrants a selective approach. We aimed to evaluate initial findings that could direct further investigation of AHT. Methods: A retrospective review of the trauma databases at a two level one pediatric trauma centers was performed. We reviewed all patients age five years and under with a diagnosis of traumatic brain injury (TBI) from 2002–2011. Results: A total of 1129 patients (mean age 1.7±1.7years; 64% male) with TBI were identified, 429 (38%) of which were the result of AHT. Complete data was available for 921 patients (82%) and were included in statistical evaluation. Forty-eight percent of patients in the AHT group had a hematocrit ≤30% on presentation compared to 19% of patients in the non-AHT group. On univariate analysis, a hematocrit of ≤30% was predictive of AHT as the cause of injury (P <.0001), as was a platelet count of greater than 400,000 (P <.0001). After controlling for age, sex, ISS, GCS on presentation, need for CPR, and survival to hospital discharge, hematocrit of ≤30% and platelets of greater than 400,000 were predictive of AHT as the cause of TBI (P <.05). Conclusions: In the setting of head injury and unclear history of trauma, a hematocrit of ≤30% on presentation increases the likelihood of abusive head trauma in children up to the age of 5years. [Copyright &y& Elsevier]

Severe acute kidney injury (AKI) is a known risk factor for infection and mortality. However, whether stage 1 AKI is a risk factor for infection has not been evaluated in adults. We hypothesized that stage 1 AKI following cardiac surgery would independently associate with infection and mortality. In this retrospective propensity score–matched study, we evaluated 1620 adult patients who underwent nonemergent cardiac surgery at the University of Colorado Hospital from 2011 to 2017. Patients who developed stage 1 AKI by Kidney Disease Improving Global Outcomes creatinine criteria within 72 hours of surgery were matched to patients who did not develop AKI. The primary outcome was an infection, defined as a new surgical-site infection, positive blood or urine culture, or development of pneumonia. Secondary outcomes included in-hospital mortality, stroke, and intensive care unit (ICU) and hospital length of stay (LOS). Stage 1 AKI occurred in 293 patients (18.3%). Infection occurred in 20.9% of patients with stage 1 AKI compared with 8.1% in the no-AKI group (P <.001). In propensity-score matched analysis, stage 1 AKI independently associated with increased infection (odds ratio [OR]; 2.24, 95% confidence interval [CI], 1.37-3.17), ICU LOS (OR, 2.38; 95% CI, 1.71–3.31), and hospital LOS (OR, 1.30; 95% CI, 1.17-1.45). Stage 1 AKI is independently associated with postoperative infection, ICU LOS, and hospital LOS. Treatment strategies focused on prevention, early recognition, and optimal medical management of AKI may decrease significant postoperative morbidity. Summary of methods and results. AKI , Acute kidney injury; ICU , intensive care unit; LOS , length of stay; OR , odds ratio; CI , confidence interval. [Display omitted] [ABSTRACT FROM AUTHOR]