Predictors of acute incisional hernia incarceration at initial hernia diagnosis on computed tomography.

BACKGROUND: Acute incisional hernia incarceration is associated with high morbidity and mortality yet there is little evidence to guide which patients will benefit most from prophylactic repair. We explored baseline computed tomography (CT) characteristics associated with incarceration. METHODS: A case-control study design was utilized to explore adults (≥18 years) diagnosed with an incisional hernia between 2010 and 2017 at a single institution with a 1-year minimum follow-up. Computed tomography imaging at the time of initial hernia diagnosis was examined. Following propensity score matching for baseline characteristics, multivariable logistic regression was performed to identify independent predictors associated with acute incarceration. RESULTS: A total of 532 patients (27.26% male, mean 61.55 years) were examined, of whom 238 experienced an acute incarceration. Between two well-matched cohorts with and without incarceration, the presence of small bowel in the hernia sac (odds ratio [OR], 7.50; 95% confidence interval [CI], 3.35-16.38), increasing sac height (OR, 1.34; 95% CI, 1.10-1.64), more acute hernia angle (OR, 0.98 per degree; 95% CI, 0.97-0.99), decreased fascial defect width (OR, 0.68; 95% CI, 0.58-0.81), and greater outer abdominal fat (OR, 1.28; 95% CI, 1.02-1.60) were associated with acute incarceration. Using threshold analysis, a hernia angle of <91 degrees and a sac height of >3.25 cm were associated with increased incarceration risk. CONCLUSION: Computed tomography features present at the time of hernia diagnosis provide insight into later acute incarceration risk. Improved understanding of acute incisional hernia incarceration can guide selection for prophylactic repair and thereby may mitigate the excess morbidity associated with incarceration. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.

Venographic classification and long-term surgical treatment outcomes for axillary-subclavian vein thrombosis due to venous thoracic outlet syndrome (Paget-Schroetter syndrome).

OBJECTIVE: We assessed the clinical presentation, operative findings, and surgical treatment outcomes for axillary-subclavian vein (AxSCV) thrombosis due to venous thoracic outlet syndrome (VTOS). METHODS: We performed a retrospective, single-center review of 266 patients who had undergone primary surgical treatment of VTOS between 2016 and 2022. The clinical outcomes were compared between the patients in four treatment groups determined by intraoperative venography. RESULTS: Of the 266 patients, 132 were male and 134 were female. All patients had a history of spontaneous arm swelling and idiopathic AxSCV thrombosis, including 25 (9%) with proven pulmonary embolism, at a mean age of 32.1 ± 0.8 years (range, 12-66 years). The timing of clinical presentation was acute (<15 days) for 132 patients (50%), subacute (15-90 days) for 71 (27%), and chronic (>90 days) for 63 patients (24%). Venography with catheter-directed thrombolysis or thrombectomy (CDT) and/or balloon angioplasty had been performed in 188 patients (71%). The median interval between symptom onset and surgery was 78 days. After paraclavicular thoracic outlet decompression and external venolysis, intraoperative venography showed a widely patent AxSCV in 150 patients (56%). However, 26 (10%) had a long chronic AxSCV occlusion with axillary vein inflow insufficient for bypass reconstruction. Patch angioplasty was performed for focal AxSCV stenosis in 55 patients (21%) and bypass graft reconstruction for segmental AxSCV occlusion in 35 (13%). The patients who underwent external venolysis alone (patent or occluded AxSCV; n = 176) had a shorter mean operative time, shorter postoperative length of stay and fewer reoperations and late reinterventions compared with those who underwent AxSCV reconstruction (patch or bypass; n = 90), with no differences in the incidence of overall complications or 30-day readmissions. At a median clinical follow-up of 38.7 months, 246 patients (93%) had no arm swelling, and only 17 (6%) were receiving anticoagulation treatment; 95% of those with a patent AxSCV at the end of surgery were free of arm swelling vs 69% of those with a long chronic AxSCV occlusion (P < .001). The patients who had undergone CDT at the initial diagnosis were 32% less likely to need AxSCV reconstruction at surgery (30% vs 44%; P = .034) and 60% less likely to have arm swelling at follow-up (5% vs 13%; P < .05) vs those who had not undergone CDT. CONCLUSIONS: Paraclavicular decompression, external venolysis, and selective AxSCV reconstruction determined by intraoperative venography findings can provide successful and durable treatment for >90% of all patients with VTOS. Further work is needed to achieve earlier recognition of AxSCV thrombosis, prompt usage of CDT, and even more effective surgical treatment.

Accuracy of Risk Estimation for Surgeons Versus Risk Calculators in Emergency General Surgery.

INTRODUCTION: Surgical risk calculators have expanded in both number and sophistication of their predictive approach. These calculators are gaining popularity as validated tools to help surgeons estimate mortality and complications following emergency general surgery (EGS). However, the accuracy of risk estimates generated by these calculators compared to risk estimation by practicing surgeons has not been explored. METHODS: Acute care surgeons at a quaternary care center prospectively estimated 30-d mortality and complications for adult EGS patients (2019-2021). Surgeon predictions were compared to Predictive OpTimal Trees in Emergency Surgery Risk (POTTER) and NSQIP estimates. Observed-to-expected (O:E) ratios of median aggregate estimates were calculated. C-statistics for surgeon and calculator estimations were utilized to quantify predictive accuracy. RESULTS: Among 150 patients (median 61 y, 45% male), 30-d mortality was 15% (n = 23). Observed rates of prolonged mechanical ventilation and acute renal failures were 30% and 10%, respectively. Overall, surgeon predictions were similar to risk calculator estimates for mortality (c-statistics 0.843 [surgeon] versus 0.848 [POTTER] and 0.815 [NSQIP]) and need for prolonged ventilation (c-statistics 0.801 versus 0.722 and 0.689, respectively). Surgeons tended to overestimate complication risks. Surgeon experience was not significantly associated with mortality prediction in an adjusted model. CONCLUSIONS: Acute care surgeons at a quaternary care center predicted postoperative mortality and complications with similar discrimination when compared to surgical risk calculators. Surgeon expertise should be utilized in conjunction with risk calculators when counseling EGS patients regarding anticipated postoperative outcomes. Surgeons should be cognizant of patterns in overestimation or underestimation of complications.

Machine learning for the prediction of pathologic pneumatosis intestinalis.

BACKGROUND: The radiographic finding of pneumatosis intestinalis can indicate a spectrum of underlying processes ranging from a benign finding to a life-threatening condition. Although radiographic pneumatosis intestinalis is relatively common, there is no validated clinical tool to guide surgical management. METHODS: Using a retrospective cohort of 300 pneumatosis intestinalis cases from a single institution, we developed 3 machine learning models for 2 clinical tasks: (1) the distinction of benign from pathologic pneumatosis intestinalis cases and (2) the determination of patients who would benefit from an operation. The 3 models are (1) an imaging model based on radiomic features extracted from computed tomography scans, (2) a clinical model based on clinical variables, and (3) a combination model using both the imaging and clinical variables. RESULTS: The combination model achieves an area under the curve of 0.91 (confidence interval: 0.87-0.94) for task I and an area under the curve of 0.84 (confidence interval: 0.79-0.88) for task II. The combination model significantly (P < .05) outperforms the imaging model and the clinical model for both tasks. The imaging model achieves an area under the curve of 0.72 (confidence interval: 0.57-0.87) for task I and 0.68 (confidence interval: 0.61-0.74) for task II. The clinical model achieves an area under the curve of 0.87 (confidence interval: 0.83-0.91) for task I and 0.76 (confidence interval: 0.70-0.81) for task II. CONCLUSION: This study suggests that combined radiographic and clinical features can identify pathologic pneumatosis intestinalis and aid in patient selection for surgery. This tool may better inform the surgical decision-making process for patients with pneumatosis intestinalis.

Leveraging Decision Curve Analysis to Improve Clinical Application of Surgical Risk Calculators.

BACKGROUND: Surgical risk calculators (SRCs) have been developed for estimation of postoperative complications but do not directly inform decision-making. Decision curve analysis (DCA) is a method for evaluating prediction models, measuring their utility in guiding decisions. We aimed to analyze the utility of SRCs to guide both preoperative and postoperative management of patients undergoing hepatopancreaticobiliary surgery by using DCA. METHODS: A single-institution, retrospective review of patients undergoing hepatopancreaticobiliary operations between 2015 and 2017 was performed. Estimation of postoperative complications was conducted using the American College of Surgeons SRC [ACS-SRC] and the Predictive OpTimal Trees in Emergency Surgery Risk (POTTER) calculator; risks were compared with observed outcomes. DCA was used to model optimal patient selection for risk prevention strategies and to compare the relative performance of the ACS-SRC and POTTER calculators. RESULTS: A total of 994 patients were included in the analysis. C-statistics for the ACS-SRC prediction of 12 postoperative complications ranged from 0.546 to 0.782. DCA revealed that an ACS-SRC-guided readmission prevention intervention, when compared with an all-or-none approach, yielded a superior net benefit for patients with estimated risk between 5% and 20%. Comparison of SRCs for venous thromboembolism intervention demonstrated superiority of the ACS-SRC for thresholds for intervention between 2% and 4% with the POTTER calculator performing superiorly between 4% and 8% estimated risk. CONCLUSIONS: SRCs can be used not only to predict complication risk but also to guide risk prevention strategies. This methodology should be incorporated into external validations of future risk calculators and can be applied for institution-specific quality improvement initiatives to improve patient outcomes.

Improved Understanding of Acute Incisional Hernia Incarceration: Implications for Addressing the Excess Mortality of Emergent Repair.

BACKGROUND: Incisional hernia develops in up to 20% of patients undergoing abdominal operations. We sought to identify characteristics associated with poor outcomes after acute incisional hernia incarceration. STUDY DESIGN: We performed a retrospective cohort study of adult patients with incisional hernias undergoing elective repair or with acute incarceration between 2010 and 2017. The primary end point was 30-day mortality. Logistic regression was used to determine adjusted odds associated with 30-day mortality. The American College of Surgeons Surgical Risk Calculator was used to estimate outcomes had these patients undergone elective repair. RESULTS: A total of 483 patients experienced acute incarceration; 30-day mortality was 9.52%. Increasing age (adjusted odds ratio 1.05; 95% CI, 1.02 to 1.08) and bowel resection (adjusted odds ratio 3.18; 95% CI, 1.45 to 6.95) were associated with mortality. Among those with acute incarceration, 231 patients (47.9%) had no documentation of an earlier surgical evaluation and 252 (52.2%) had been evaluated but had not undergone elective repair. Among patients 80 years and older, 30-day mortality after emergent repair was high (22.9%) compared with estimated 30-day mortality for elective repair (0.73%), based on the American College of Surgeons Surgical Risk Calculator. Estimated mortality was comparable with observed elective repair mortality (0.82%) in an age-matched cohort. Similar mortality trends were noted for patients younger than 60 years and aged 60 to 79 years. CONCLUSIONS: Comparison of predicted elective repair and observed emergent repair mortality in patients with acute incarceration suggests that acceptable outcomes could have been achieved with elective repair. Almost one-half of acute incarceration patients had no earlier surgical evaluation, therefore, targeted interventions to address surgical referral can potentially result in fewer incarceration-related deaths.