Why Not This Case? Differences Between Resident and Attending Operative Cases at Teaching Hospitals.

INTRODUCTION: Previous studies have focused on outcomes pertaining to resident operative autonomy, but there has been little academic work examining the types of patients and cases where autonomy is afforded. We sought to describe the differences between surgical patient populations in teaching cases where residents are and are not afforded autonomy. METHODS: We examined all general and vascular operations at Veterans Affairs teaching hospitals from 2004 to 2019 using Veterans Affairs Surgical Quality Improvement Program. Level of resident supervision is prospectively recorded by the operating room nurse at the time of surgery: attending primary (AP): the attending performs the case with or without a resident; attending resident (AR): the resident performs the case with the attending scrubbed; resident primary (RP): resident operating with supervising attending not scrubbed. Resident (R) cases refer to AR + RP. Patient demographics, comorbidities, level of supervision, and top cases within each group were evaluated. RESULTS: A total of 618,578 cases were analyzed; 154,217 (24.9%) were AP, 425,933 (68.9%) AR, and 38,428 (6.2%) RP. Using work relative value unit as a surrogate for complexity, RP was the least complex compared to AP and AR (10.4/14.4/14.8, P < 0.001). RP also had a lower proportion of American Society of Anesthesiologists 3 and 4 + 5 patients (P < 0.001), were younger (P < 0.001), and generally had lower comorbidities. The most common RP cases made up a higher proportion of all RP cases than they did for AP/AR and demonstrated several core competencies (hernia, cholecystectomy, appendectomy, amputation). R cases, however, were generally sicker than AP cases. CONCLUSIONS: In the small proportion of cases where residents were afforded autonomy, we found they were more focused on the core general surgery cases on lower risk patients. This selection bias likely demonstrates appropriate attending judgment in affording autonomy. However, this cohort consisted of many "sicker" patients and those factors alone should not disqualify resident involvement.

Did Residents Stop Operating During COVID? Impact of COVID-19 Across VA Teaching Hospitals on Surgical Resident Education.

BACKGROUND: During the COVID-19 pandemic, elective cases across the nation were suspended, leading to major decreases in operative volume for surgical trainees. Surgical resident operative autonomy has been declining over time, so we sought to explore the effect COVID-19 had on resident autonomy within VA teaching hospitals. METHODS: A retrospective analysis of surgical cases across specialties was performed using the VA Surgical Quality Improvement Program database from September 2019 to September 2021 at VA teaching hospitals. Supervision codes are recorded prospectively: attending surgeon performs the operation (AP), resident completes majority of the case with the attending scrubbed (AR), and resident is primary surgeon without attending scrubbed (RP). RESULTS: 20,457 cases pre-COVID decreased to 11,035 during peak-COVID (P < .001). Overall, RP cases increased from 6.5% to 7.6% during the peak (P < .001) and trended back downwards during the recovery periods. AP decreased initially (29.9%-27.7%, P < .001), but regressed back to pre-pandemic numbers. In general surgery RP cases, urgent cases such as laparoscopic cholecystectomies increased from 18.8% to 27.5%, while elective repairs decreased during the peak. Similar changes were noted across specialties. DISCUSSION: Operative cases dropped by half from pre- to peak- COVID and remained 20% below pre-pandemic volume the following year. Interestingly, RP rates increased for several specialties during the peak of the pandemic, which may have resulted from a relative higher ratio of resident personnel:case volume and shift in case distribution from elective to urgent. The increase in RP rate has begun to regress to pre-COVID levels which need to be readdressed.

A Prospective Study of Machine Learning-Assisted Radiation Therapy Planning for Patients Receiving 54 Gy to the Brain.

PURPOSE: The capacity for machine learning (ML) to facilitate radiation therapy (RT) planning for primary brain tumors has not been described. We evaluated ML-assisted RT planning with regard to clinical acceptability, dosimetric outcomes, and planning efficiency for adults and children with primary brain tumors. METHODS AND MATERIALS: In this prospective study, children and adults receiving 54 Gy fractionated RT for a primary brain tumor were enrolled. For each patient, one ML-assisted RT plan was created and compared with 1 or 2 plans created using standard ("manual") planning procedures. Plans were evaluated by the treating oncologist, who was blinded to the method of plan creation. The primary endpoint was the proportion of ML plans that were clinically acceptable for treatment. Secondary endpoints included the frequency with which ML plans were selected as preferable for treatment, and dosimetric differences between ML and manual plans. RESULTS: A total of 116 manual plans and 61 ML plans were evaluated across 61 patients. Ninety-four percent of ML plans and 93% of manual plans were judged to be clinically acceptable (P = 1.0). Overall, the quality of ML plans was similar to manual plans. ML plans comprised 34.5% of all plans evaluated and were selected for treatment in 36.1% of cases (P = .82). Similar tumor target coverage was achieved between both planning methods. Normal brain (brain minus planning target volume) received an average of 1 Gy less mean dose with ML plans (compared with manual plans, P < .001). ML plans required an average of 45.8 minutes less time to create, compared with manual plans (P < .001). CONCLUSIONS: ML-assisted automated planning creates high-quality plans for patients with brain tumors, including children. Plans created with ML assistance delivered slightly less dose to normal brain tissues and can be designed in less time.

Surgical resident operative autonomy on nights and weekends: What happens to surgical education during off-hours?

BACKGROUND: Surgical resident operative autonomy is critical for trainee maturation to independence. Acute care surgery (ACS) cases commonly occur off-hours and tension between operating room availability and on-call staff can affect resident operative autonomy. We examined operative resident autonomy for general, vascular, and thoracic (GVT) surgery during nights and weekends. We hypothesized that residents would be afforded less operative autonomy during off - hours than weekdays. METHODS: This retrospective cohort study uses the Veterans Affairs Surgical Quality Improvement Program database, we examined all GVT cases at Veterans Affairs teaching hospitals from 2004 to 2019. All cases are coded for the level of supervision at the time of surgery: AP, attending primary surgeon; AR, attending and resident operating together; and RP, resident primary (attending supervising but not scrubbed). Cases starting between 6 pm to 7 am Monday through Friday were considered nights, cases on Saturday/Sunday were considered weekends, and collectively considered "off-hours." Resident primary case rates were compared by start time and type. RESULTS: Over the 15-year study period, there were 666,421 GVT cases performed with 38,097 cases (6%) performed off-hours. During off-hours, 31,396 (83%) were ACS compared with 5% of daytime cases. Overall, off-hours cases have higher RP rate than daytime cases (6.8% vs. 5.8%, p < 0.001). Daytime ACS cases have higher rates of RP than nights/weekends (7.6% vs. 6.8%, p < 0.001). Conversely, daytime elective cases have lower RP than nights (5.7% vs. 7.9%, p < 0.001). During off-hours, there are more RP cases on nights compared with weekends (7.1% vs. 6.5%, p = 0.02). CONCLUSION: Overall, residents were afforded more operative autonomy during off-hours, with nights having greater RP than weekends. In contrast, ACS cases have more autonomy during weekdays. These data have potentially significant implications for ACS service staffing, night float rotations, and overall resident operative experience on ACS services. LEVEL OF EVIDENCE/STUDY TYPE: Prognostic and Epidemiological; Level III.

Patient inequities in affording surgical resident operative autonomy at Veterans Affairs teaching hospitals, does it extend to female patients?

BACKGROUND: Examining surgical resident operative autonomy within the Veterans Affairs (VA) System, we previously showed residents were afforded autonomy more frequently on Black patients. We hypothesized that, compared to males, female surgical patients receive less attending involvement and more resident autonomy during surgery. METHODS: Retrospective review of all general/vascular surgeries performed at teaching VA hospitals from 2004 to 2019. Operative procedures are coded at the time of surgery as attending primary surgeon (AP), attending with resident (AR), or resident primary surgeon--attending not scrubbed (RP). The primary outcome was the difference in supervision rates between patient sexes. RESULTS: 618,578 operations were examined-24.9% AP, 68.9% AR, and 6.2% RP. Overall, 5.9% of cases were performed on women. The rate of RP cases was higher in males compared to females (6.3% vs 5.3%, p < 0.001). CONCLUSION: Female veterans are less likely to have residents operate on them autonomously. Reasons for this require further characterization.

Estimating Potential Benefits to Neurocognition with Proton Therapy in Adults with Brain Tumors.

Purpose: Photon radiation therapy (RT) is important in the treatment of many brain tumors but can negatively affect neurocognition. Proton therapy (PT) can reduce doses to normal brain structures. We compared photon and proton plans to estimate the potential benefit in cognition if the patient were treated with PT. Materials and Methods: We analyzed 23 adult patients with proton and photon plans for the treatment of a primary brain tumor. Cognitive outcomes were predicted using converted equivalent dose (EQD2) with an α/ß ratio of 3 to left temporal lobe and normal brain tissue. Risks of cognitive decline on 2 specific tests, the Controlled Oral Word Association Test (COWAT [letter S], a test of verbal fluency) and the Wechler Adult Intelligence Scale (WAIS-IV Coding Test, a test of processing speed) were derived from a previously published model. Results: Dose reductions to left temporal lobe and normal brain tissue translated into lower estimated probabilities of impairment in specific neurocognitive test scores after PT. With a mean dose reduction from 1490 to 1092 cGy in EQD2 to the left temporal lobe (P < .001), there was reduction in probability of impairment in the COWAT (Letter S) test from 6.8% to 5.4%. Similar results were seen with the normal brain (750 to 451 cGy in EQD2, P < .001), with reduction in probability of impairment in the WAIS-IV Coding test from 5% to 4.1%. Other structures experiencing dose reduction with PT included each cochlea, posterior fossa, each temporal lobe, and each hippocampus. Conclusion: We confirmed an association between PT and lower doses to brain substructures, which is expected to result in a modest decrease in probability of impairment in neurocognitive test scoring. These findings should be confirmed in prospective cohorts of patients treated with PT.

Anterior Abdominal Varicosities Due to Unilateral Common and External Iliac Vein Occlusion Five Decades Post-Injury.

Abdominopelvic varicosities are a rare occurrence after traumatic venous injuries. Several disorders exist that present with abdominopelvic varicosities such as May-Thurner syndrome, pelvic congestion syndrome, and nutcracker syndrome; however, it has rarely been described after trauma.1 We present a case in 70-year-old male, who in 1974 sustained a penetrating injury from fragments secondary to mortar explosion, requiring exploratory laparotomy. He presented to the hospital with abdominopelvic varicosities that began 20 years after the incident and was asymptomatic at initial presentation. While there is a known case report of congenital absence of a common iliac vein in a young, healthy, athletic man who developed abdominopelvic varicosities, this is the first case report, to our knowledge, of evolution of a traumatic injury of this nature over a lifetime. Pathophysiology, diagnostics, risks of ligation, and management of chronic abdominopelvic varicosities in this patient are discussed.

Electric scooter sharing systems: An analysis of injury patterns associated with their introduction.

BACKGROUND: With the increasing popularity of electric scooters (ES) and the introduction of ES sharing systems in 2017, hospitals are seeing more ES-related injuries. The effects of sharing systems on traumatic injuries are lacking in the literature. We, therefore, sought to describe trends in ES injuries. METHODS: The Nationwide Inpatient Sample was queried for patients hospitalized with ES-related injuries in the United States from 2015 to 2019. Admissions due to ES were divided into two cohorts: before (≤2017) and after (>2018) the introduction of sharing systems. Patients were stratified by injuries sustained, age, gender, and race. Inpatient hospital charges and length of stay were compared. Exclusion criteria included patients older than 65 and patients with neurological disorders. Traumatic injuries were compared after adjusting for age, gender, and race in a multivariate logistic regression analysis. RESULTS: During the study period, there were 686 admissions, of which 220 remained due to exclusion criteria. There was a consistent increase in ES-related injuries over the years (r = 0.91, p = 0.017). Patients who were injured after the introduction of sharing systems were more likely to sustain facial fractures (OR, 2.63; 95%CI, 1.30-5.32; p = 0.007) after controlling for age, gender, and race. The incidence of lumbar and pelvic fractures was higher following the introduction of such systems (7.1% vs. 0%; p<0.05). CONCLUSIONS: The introduction of ES sharing systems resulted in increased incidence of facial, pelvic, and lumbar fractures. Federal and state regulations need to be implemented to mitigate the detrimental effects of ES sharing systems.

Simple and effective immobilization for radiation treatment of choroidal melanoma.

At our institution, patients diagnosed with choroidal melanoma requiring external beam radiation therapy are treated with two 6 MV volumetric-modulated arcs delivering 50 Gy over 5 daily fractions. The patient is immobilized using an Orfit head and neck mask and is directed to look at a light emitting diode (LED) during CT simulation and treatment to minimize eye movement. Patient positioning is checked with cone beam computed tomography (CBCT) daily. Translational and rotational displacements greater than 1 mm or 1° off the planned isocenter position are corrected using a Hexapod couch. The aim of this study is to verify that the mask system provides adequate immobilization and to verify our 2-mm planning target volume (PTV) margins are sufficient. Residual displacements provided by pretreatment verification and post-treatment CBCT data sets were used to assess the impact of patient mobility during treatment on the reconstructed delivered dose to the target and organs at risk. The PTV margin calculated using van Herk's method1 was used to assess patient motion plus other factors that affect treatment position, such as kV-MV isocenter coincidence. Patient position variations were small and were shown to not cause significant dose variations between the planned and reconstructed dose to the target and organs at risk. The PTV margin analysis showed patient translational motion alone required a PTV margin of 1 mm. Given other factors that affect treatment delivery accuracy, a 2-mm PTV margin was shown to be sufficient for treatment of 95% of our patients with 100% of dose delivered to the GTV. The mask immobilization with LED focus is robust and we showed a 2-mm PTV margin is adequate with this technique.

A pilot study of machine-learning based automated planning for primary brain tumours.

PURPOSE: High-quality radiotherapy (RT) planning for children and young adults with primary brain tumours is essential to minimize the risk of late treatment effects. The feasibility of using automated machine-learning (ML) to aid RT planning in this population has not previously been studied. METHODS AND MATERIALS: We developed a ML model that identifies learned relationships between image features and expected dose in a training set of 95 patients with a primary brain tumour treated with focal radiotherapy to a dose of 54 Gy in 30 fractions. This ML method was then used to create predicted dose distributions for 15 previously-treated brain tumour patients across two institutions, as a testing set. Dosimetry to target volumes and organs-at-risk (OARs) were compared between the clinically-delivered (human-generated) plans versus the ML plans. RESULTS: The ML method was able to create deliverable plans in all 15 patients in the testing set. All ML plans were generated within 30 min of initiating planning. Planning target volume coverage with 95% of the prescription dose was attained in all plans. OAR doses were similar across most structures evaluated; mean doses to brain and left temporal lobe were lower in ML plans than manual plans (mean difference to left temporal, - 2.3 Gy, p = 0.006; mean differences to brain, - 1.3 Gy, p = 0.017), whereas mean doses to right cochlea and lenses were higher in ML plans (+ 1.6-2.2 Gy, p < 0.05 for each). CONCLUSIONS: Use of an automated ML method to aid RT planning for children and young adults with primary brain tumours is dosimetrically feasible and can be successfully used to create high-quality 54 Gy RT plans. Further evaluation after clinical implementation is planned.

Distinct Cellular Profiles of Hif1a and Vegf mRNA Localization in Microglia, Astrocytes and Neurons during a Period of Vascular Maturation in the Auditory Brainstem of Neonate Rats.

Defining the relationship between vascular development and the expression of hypoxia-inducible factors (Hifs) and vascular endothelial growth factor (Vegf) in the auditory brainstem is important to understand how tissue hypoxia caused by oxygen shortage contributes to sensory deficits in neonates. In this study, we used histology, molecular labeling, confocal microscopy and 3D image processing methods to test the hypothesis that significant maturation of the vascular bed in the medial nucleus of the trapezoid body (MNTB) occurs during the postnatal period that precedes hearing onset. Isolectin-B4 histochemistry experiments suggested that the MNTB vasculature becomes more elaborate between P5 and P10. When combined with a cell proliferation marker and immunohistochemistry, we found that vascular growth coincides with a switch in the localization of proliferating cells to perivascular locations, and an increase in the density of microglia within the MNTB. Furthermore, microglia were identified as perivascular cells with proliferative activity during the period of vascular maturation. Lastly, combined in situ hybridization and immunohistochemistry experiments showed distinct profiles of Hif1a and Vegf mRNA localization in microglia, astrocytes and MNTB principal neurons. These results suggest that different cells of the neuro-glio-vascular unit are likely targets of hypoxic insult in the auditory brainstem of neonate rats.

Posttreatment complications of early-stage prostate cancer patients: brachytherapy versus three-dimensional conformal radiation therapy.

PURPOSE: The purpose of this study was to compare treatment complications for early-stage prostate cancer managed by either brachytherapy or three-dimensional conformal radiotherapy (3D-CRT). MATERIALS AND METHODS: [corrected] Records were reviewed for 86 men treated with transperineal interstitial permanent prostate brachytherapy and for 76 men treated with dose-escalated (75.6-Gy) six-field 3DCRT between 1998 and 2000. Median ages were 65 and 66 years, respectively; median Gleason scores were 6 and 7; baseline prostate-specific antigen levels were 6.1 and 9.0 ng/mL; and the follow-up period was 42 months. In the urinary domain, patients who underwent brachytherapy recorded an International Prostate Symptom Score prospectively at baseline, as well as 3 months and every 6 months following, whereas patients who underwent 3D-CRT were assigned a Radiation Therapy Oncology Group (RTOG) late toxicity score at similar time intervals. In the bowel domain, RTOG late toxicity score was used for both groups, and physician-dictated notes were used to assess sexual function. All patients who underwent brachytherapy were prescribed tamsulosin (Flomax) to manage urinary symptoms for a minimum of 3 months after treatment. RESULTS: With respect to urinary symptoms, a direct comparison cannot be made between the International Prostate Symptom Score and the RTOG late toxicity score. Nonetheless, it was evident that patients who underwent brachytherapy had more severe urinary sequelae in the months after implantation. Tamsulosin was still being used by 78% of patients at 6 months, decreasing to 55% at 1 year and 27% at 2 years. Intermittent self-catheterization was required at 6 months after treatment by 5% of patients who underwent brachytherapy, and a transurethral resection of the prostate was performed in one of these patients at 12 months. In patients who underwent 3D-CRT, 14% used tamsulosin at some point in the follow-up period and none required catheterization or transurethral resection of the prostate. In the bowel domain, 20% of patients who underwent brachytherapy experienced grade 1 gastrointestinal toxicity, most within the first 12 months of follow-up, compared with 30% grade 1 or 2 gastrointestinal scores in the 3D-CRT group (peaking in the second year after treatment). In the sexual domain, 9% of patients who underwent brachytherapy who were previously potent reported a loss of potency by 18 months, compared with 53% of patients who underwent 3D-CRT. Without the help of sildenafil (Viagra), these figures rose to 24% and 58%. CONCLUSIONS: 3D-CRT is associated with fewer urinary symptoms, whereas brachytherapy has a more favorable toxicity profile for bowel and sexual function. In the absence of a randomized clinical trial, such a comparison can be helpful both in counseling patients as to what to expect from either treatment and in facilitating their treatment decision process.