Goals, Structure and Financing of Surgical Residency Training: A Subcommittee Report of the Blue Ribbon Committee II.

OBJECTIVE: As part of the Blue Ribbon Committee II, review current goals, structure and financing of surgical training in Graduate Medical Education (GME) and recommend needed changes. SUMMARY BACKGROUND DATA: Surgical training has continually undergone major transitions with the 80-hour work week, earlier specialization (vascular, plastics and cardiovascular) and now entrustable professional activities (EPAs) as part of competency based medical education (CBME). Changes are needed to ensure the efficiencies of CBME are utilized, that stable graduate medical education funding is secured, and that support for surgeons who teach is made available. METHODS: Convened subcommittee discussions to determine needed focus for recommendations. RESULTS: Five recommendations are offered for changes to GME financing, incorporation of CBME, and support for educators, students and residents in training. CONCLUSIONS: Changes in surgical training related to CBME offer opportunity for change and innovation. Our subcommittee has laid out a potential path forward for improvements in GME funding, training structure, compensation of surgical educators, and support of students and residents in training.

Ultrafast Photoinduced Phase Change in SnSe.

Time-resolved multiterahertz (THz) spectroscopy is used to observe an ultrafast, nonthermal electronic phase change in SnSe driven by interband photoexcitation with 1.55 eV pump photons. The transient THz photoconductivity spectrum is found to be Lorentzian-like, indicating charge localization and phase segregation. The rise of photoconductivity is bimodal in nature, with both a fast and slow component due to excitation into multiple bands and subsequent intervalley scattering. The THz conductivity magnitude, dynamics, and spectra show a drastic change in character at a critical excitation fluence of approximately 6 mJ/cm^{2} due to a photoinduced phase segregation and a macroscopic collapse of the band gap.

Understanding the temporal dynamics of invasive late blight populations in India for improved management practices.

The microbial oomycete pathogen, Phytophthora infestans causes severe epidemics of potato late blight in crops globally. Disease management benefits from an understanding of the diversity of pathogen populations. In this study, we explore the dynamics of P. infestans populations in the late blight-potato agro-ecosystem across the Indian subcontinent. Investigations of the macroecological observations at the field level and microbial ecological principles provided insights into future pathogen behaviour. We use a comprehensive simple sequence repeat allele dataset to demonstrate that an invasive clonal lineage called EU_13_A2 has dominated populations over 14 years across India, Bangladesh, and Pakistan. Increasing levels of sub-clonal variation were tracked over time and space and, for the first time, populations in Asia were also compared to the source populations from Europe. Within India, a regional pathogen population structure was observed with evidence for local migration, cross-border movement between surrounding countries, and introductions via imports. There was also evidence of genetic drift and between-season transmission of more strongly pathogenic sub-clones with a complete displacement of some sub-clonal types. The limited introduction of novel genotypes and the use of resistant potato cultivars could contribute to the dominance of the 13_A2 lineage. The insights will contribute to the management of the pathogen in these key global potato production regions.

Leaving trusted paths: Estimating corneal keratometric index in cataract surgery eyes with zero-power implants.

PURPOSE: This study aimed to estimate the corneal keratometric index in the eyes of cataract surgery patients who received zero-power intraocular lenses (IOLs). METHODOLOGY: This retrospective study analyzed postoperative equivalent spherical refraction and axial length, mean anterior curvature radius and aqueous humor refractive index to calculate the theoretical corneal keratometric index value (nk). Data was collected from 2 centers located in France and Germany. RESULTS: Thirty-six eyes were analyzed. The results revealed a mean corneal keratometric index of 1.329 ± 0.005 for traditional axial length (AL) and 1.331 ± 0.005 for Cooke modified axial length (CMAL). Results ranged from minimum values of 1.318/1.320 to maximum values of 1.340/1.340. CONCLUSION: The corneal keratometric index is a crucial parameter for ophthalmic procedures and calculations, particularly for IOL power calculation. Notably, the estimated corneal keratometric index value of 1.329/1.331 in this study is lower than the commonly used 1.3375 index. These findings align with recent research demonstrating that the theoretical corneal keratometric index should be approximately 1.329 using traditional AL and 1.331 using CMAL, based on the ratio between the mean anterior and posterior corneal curvature radii (1.22).

Change in refractive errors with changes in IOL parameters.

This study considered two questions associated with intraocular lens (IOL) power and refraction: (1) Given a refraction with a particular IOL in the eye, what will be the refraction for the IOL or another IOL if located differently with regard to tilt or anterior-posterior position? (2) For a target refraction, what is the power of another IOL if located differently with regard to tilt or position? A thin lens technique was developed to address these questions. For the first question, light was traced through the initial correcting spectacle lens to the cornea, refracted at the cornea, transferred to the position of the initial IOL, refracted at this IOL, transferred to the position of a new IOL (which may be the same IOL but with a different position and/or tilt), refracted backwards through the new IOL, transferred to the cornea and refracted out of the eye to give a new correcting spectacle lens power. For the second question, light was traced through the initial correcting spectacle lens to the cornea, refracted at the cornea, transferred to the position of the initial IOL, refracted at the initial IOL and transferred to the position of a new IOL. Light was also traced through the second correcting spectacle lens, refracted at the cornea and transferred to the position of the second IOL. The difference between the reduced image vergence for the first raytrace and the reduced object vergence for the second raytrace gave the effective power of the second IOL, and from this, the power of the second IOL was determined. Examples are presented for different situations, including a case report.

Refractive errors occurring with tilt of intraocular lenses.

A thin lens technique was developed to determine how the effective powers of toric monofocal intraocular lenses (IOLs) are influenced by tilt and the refractive errors associated with the tilt. A series of steps determined the effective power of the cornea at the IOL, the IOL power, the effective power of the tilted IOL, the correction required at the front of the eye and the power of an IOL that would compensate for the tilt. The correction was determined by starting at the ideal reduced image vergence at the IOL, backwards raytracing to obtain a reduced image vergence at the cornea, and subtracting the cornea power from this reduced image vergence. Examples are presented for different situations where the IOL is either tilted about the vertical or an oblique axis. Raytracing with a thick lens verified the accuracy of the technique.

The Variability of Phytophthora infestans Isolates Collected from Estonian Islands in the Baltic Sea.

Knowledge of a pathogen's genetic variability and population structure is of great importance to effective disease management. In this study, 193 isolates of Phytophthora infestans collected from three Estonian islands were characterized over 3 years using simple sequence repeat (SSR) marker data complemented by information on their mating type and resistance to metalaxyl. In combination with SSR marker data from samples in the neighboring Pskov region of Northwest Russia, the impact of regional and landscape structure on the level of genetic exchange was also examined. Among the 111 P. infestans isolates from Estonian islands, 49 alleles were detected among 12 SSR loci, and 59 SSR multilocus genotypes were found, of which 64% were unique. The genetic variation was higher among years than that among islands, as revealed by the analysis of molecular variance. The frequency of metalaxyl-resistant isolates increased from 9% in 2012 to 30% in 2014, and metalaxyl resistance was most frequent among A1 isolates. The test for isolation by distance among the studied regions was not significant, and coupled with the absence of genetic differentiation, the result revealed gene flow and the absence of local adaptation. The data are consistent with a sexual population in which diversity is driven by an annual germination of soilborne oospores. The absence of shared genotypes over the years has important implications when it comes to the management of diseases. Such population diversity can make it difficult to predict the nature of the outbreak in the coming year as the genetic makeup is different for each year.

Esophageal and Esophagogastric Junction Cancers, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology.

Cancers originating in the esophagus or esophagogastric junction constitute a major global health problem. Esophageal cancers are histologically classified as squamous cell carcinoma (SCC) or adenocarcinoma, which differ in their etiology, pathology, tumor location, therapeutics, and prognosis. In contrast to esophageal adenocarcinoma, which usually affects the lower esophagus, esophageal SCC is more likely to localize at or higher than the tracheal bifurcation. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability status, and the expression of programmed death-ligand 1, has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, ipilimumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with locally advanced esophageal or esophagogastric junction cancers. This selection from the NCCN Guidelines for Esophageal and Esophagogastric Junction Cancers focuses on the management of recurrent or metastatic disease.

Racial Health Disparities Research in Cardiothoracic Surgery Under-represented in Major Meetings.

INTRODUCTION: Black/African Americans and Latinos face significant health disparities and systemic inequities. Heart and lung disease are leading factors affecting morbidity and mortality in these groups. Given this disparity, we sought to determine how often this topic is presented at the most relevant United States annual cardiothoracic surgery meetings. METHODS: Specialty-specific annual meeting abstract books were queried between 2015 and 2021. We included the Society of Thoracic Surgeons, American Association for Thoracic Surgery, Western Thoracic Surgical Association, and the Southern Thoracic Surgical Association. Scientific abstract titles and content were searched for the following keywords and phrases: "racial health disparities," "race," "racism," "racial bias," "institutional racism," and "health disparities". If an abstract included a keyword or phrase, it was counted as a racial health disparity abstract. We calculated the proportion of racial health disparity abstracts and abstracts published as manuscripts in the meeting-associated journals. RESULTS: A total of 3664 abstracts were presented between 2015 and 2021. Of those, 0.90% (33/3664) abstracts presented contained at least one of the keywords or phrases. Of these abstracts, the percentage that went on to publication represented 0.38% (14/3664) of the total number of abstracts presented. CONCLUSIONS: Abstracts on racial health disparities in cardiothoracic surgery represent a very small fraction of total meeting peer-reviewed content. There is a significant gap in research to identify and develop best practice strategies to address these disparities and mitigate structural racism within the care of underserved patients with cardiothoracic diseases.

Four-flanged polypropylene optic piercing technique for scleral fixation of multifocal intraocular lens.

BACKGROUND: To evaluate the feasibility of creating flanges using an optic piercing technique with a 6 - 0 polypropylene monofilament for scleral fixation of dislocated one-piece diffractive multifocal intraocular lenses (IOLs). STUDY DESIGN: Experimental study and case series. SUBJECTS: Optical bench test and eyes with IOL dislocation. METHODS: Two separate 6 - 0 polypropylenes were penetrated twice at the opposite peripheral optic of the TECNIS Synergy IOL (Johnson & Johnson Vision). The root mean square of the modulation transfer function (MTFRMS), at between + 1.00 and - 4.00 D of defocus, was measured in the TECNIS Synergy IOL both with and without optic piercing in the optical bench study. This case series included three eyes from two patients who underwent scleral-fixation of multifocal IOLs using the four-flanged polypropylene optic piercing technique. The postoperative corrected distance visual acuity (CDVA) at 4 m, the uncorrected near visual acuity (UNVA) at 40 cm, and IOL centration were evaluated. RESULTS: The optical bench test showed no differences in MTFRMS values measured in the TECNIS Synergy IOL, either with or without optic piercing at all defocuses. In all three case series, the postoperative CDVA at 4 m was 20/20 and UNVA at 40 cm was J1. Postoperative anterior segment photographs showed good centration of IOLs in all cases. CONCLUSION: The four-flanged polypropylene optic piercing technique for multifocal IOL scleral fixation can provide excellent clinical outcomes and IOL stability after surgery without diminishing the performance of the multifocal IOLs.

Nanoscale force sensing of an ultrafast nonlinear optical response.

The nonlinear optical response of a material is a sensitive probe of electronic and structural dynamics under strong light fields. The induced microscopic polarizations are usually detected via their far-field light emission, thus limiting spatial resolution. Several powerful near-field techniques circumvent this limitation by employing local nanoscale scatterers; however, their signal strength scales unfavorably as the probe volume decreases. Here, we demonstrate that time-resolved atomic force microscopy is capable of temporally and spatially resolving the microscopic, electrostatic forces arising from a nonlinear optical polarization in an insulating dielectric driven by femtosecond optical fields. The measured forces can be qualitatively explained by a second-order nonlinear interaction in the sample. The force resulting from this nonlinear interaction has frequency components below the mechanical resonance frequency of the cantilever and is thus detectable by regular atomic force microscopy methods. The capability to measure a nonlinear polarization through its electrostatic force is a powerful means to revisit nonlinear optical effects at the nanoscale, without the need for emitted photons or electrons from the surface.

First report of Phytophthora infestans lineage EU23 causing potato and tomato late blight in South Africa.

In South Africa, potato (Solanum tuberosum) late blight epidemics from 1996 to 2007 were caused by Phytophthora infestans clonal lineage US-1 (McLeod et al. 2001; Pule et al. 2013). Similarly, surveys on tomatoes in the mid-1990s only identified the US-1 clonal lineage in South Africa (McLeod et al., 2001). On potatoes, populations from the Southern Cape and Western Cape regions consisted of persistent mefenoxam-resistant populations (McLeod et al. 2001; Pule et al. 2013). Limited mefenoxam (R-enantiomer of metalaxyl) screening in 2021 in the Western Cape showed that potato isolates were sensitive, which prompted our study. Potato late blight samples were collected in 13 potato fields in the 2021 to 2023 seasons in the Western Cape (n = 4), Free State (n = 7), Limpopo (n = 1) and Kwazulu-Natal (n = 1) Provinces, and one tomato sample in 2022 in the Limpopo Province. Fourteen samples, one per field, were simple sequence repeat (SSR) genotyped for 12 loci (Li et al. 2013) using as DNA template, FTA cards, or genomic DNA extracted from cultures. P. infestans isolations from lesions and DNA culture extractions were conducted as previously described (Pule et al. 2013). SSR genotyping revealed that all 14 P. infestans samples belonged to clonal lineage EU_23_A1 (EU23), which has a phenotype (A1 and metalaxyl sensitive) and SSR genotype matching the US-23 lineage (Saville et al., 2021). As expected, minor polymorphisms were detected among the samples at loci Pi02, G11, D13 and SSR4. Mefenoxam sensitivity testing of seven potato isolates from the Free State (n = 3) and Western Cape (n = 4), and one tomato isolate was conducted as previously described (Mcleod et al. 2001). All isolates were sensitive to mefenoxam since no infection and sporulation occurred at 3 µg/ml. This was expected since EU23 has been reported as mefenoxam sensitive in other countries (Kawchuk et al., 2011; McGrath et al., 2015). Replacement of the US-1 clonal lineage by EU23 suggests that the latter lineage is more aggressive or fit than US-1, but this must be verified especially on potatoes. On tomatoes, on the other hand, EU23 is known as a highly aggressive lineage (Kawchuk et al., 2011; McGrath et al., 2015; Saville et al., 2021). Therefore, population displacements may have first occurred on tomatoes from where the lineage spread to potatoes. In the Cape coastal potato production regions, population displacement may have been supported by the withdrawal of mefenoxam/metalaxyl from the region since 1996 because the EU23 lineage is mefenoxam sensitive, as opposed to the previously prevailing US-1 mefenoxam-resistant lineage. More severe potato late blight epidemics has not been observed in recent years in South Africa. However, tomato late blight has increased and is more prevalent in the Limpopo province. The source of the introduction of EU23 into South Africa is unknown. Only test-tube plants and/or greenhouse tubers may be imported into South Africa since 1997. Therefore, the illegal importation of planting material may have introduced the new genotype. Whether this could have occurred from neighbouring African countries is unknown since P. infestans genotyping has not been conducted in these countries. In Africa, EU23 has been reported in northern African countries (Tunisia, Algeria and Egypt) (Saville et al., 2021; El-Ganainy et al., 2023). Mefenoxam and metalaxyl applications will likely be effective again in the Western Cape, but more samples will have to be tested to confirm this. This will provide growers with a more cost-effective fungicide (metalaxyl) since alternative actives with comparable systemic and curative activity are more expensive.

Can the Risk Analysis Index for Frailty Predict Morbidity and Mortality in Patients Undergoing High-risk Surgery?

OBJECTIVE: To determine the effectiveness of the revised Risk Analysis Index (RAI-rev), administrative Risk Analysis Index (RAI-A), cancer-corrected Risk Analysis Index [RAI-rev (cancer-corrected)], and 5-variable modified Frailty Index for predicting 30-day morbidity and mortality in patients undergoing high-risk surgery. BACKGROUND: There are several frailty composite measures, but none have been evaluated for predicting morbidity and mortality in patients undergoing high-risk surgery. METHODS: Using the National Surgical Quality Improvement Program database, we performed a retrospective study of patients who underwentcolectomy/proctectomy, coronary artery bypass graft (CABG), pancreaticoduodenectomy, lung resection, or esophagectomy from 2006 to 2017. RAI-rev, RAI-A, RAI-rev (cancer corrected), and 5-variable modified Frailty Index scores were calculated. Pearson's chi-square tests and C-statistics were used to assess the predictive accuracy of each score's logistic regression model. RESULTS: In the cohort of 283,545 patients, there were 178,311 (63%) colectomy/proctectomy, 38,167 (14%) pancreaticoduodenectomy, 40,328 (14%) lung resection, 16,127 (6%) CABG, and 10,602 (3%) esophagectomy cases. The RAI-rev was a fair predictor of mortality in the total cohort (C-statistic, 0.71, 95% CI 0.70-0.71, P < 0.001) and for patients who underwent colectomy/proctectomy (C-statistic 0.73, 95% CI 0.72-0.74, P < 0.001) and CABG (C-statistic 0.70, 95% CI 0.68-0.73, P < 0.001), but a poor predictor of mortality in all other operation cohorts. The RAI-A was a fair predictor of mortality for colectomy/proctectomy patients (C-statistic 0.74, 95% CI 0.73- 0.74, P < 0.001). All indices were poor predictors of morbidity. The RAI-rev (cancer corrected) did not improve the accuracy of morbidity and mortality prediction. CONCLUSION: The presently studied frailty indices are ineffective predictors of 30-day morbidity and mortality for patients undergoing high-risk operations.

Gastric Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

Gastric cancer is the third leading cause of cancer-related deaths worldwide. Over 95% of gastric cancers are adenocarcinomas, which are typically classified based on anatomic location and histologic type. Gastric cancer generally carries a poor prognosis because it is often diagnosed at an advanced stage. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability (MSI) status, and the expression of programmed death-ligand 1 (PD-L1), has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with localized gastric cancer. This selection from the NCCN Guidelines for Gastric Cancer focuses on the management of unresectable locally advanced, recurrent, or metastatic disease.

Examining Phenotypic Traits Contributing to the Spread in Northern European Potato Crops of EU_41_A2, a New Clonal Lineage of Phytophthora infestans.

Until recently, genotypes of Phytophthora infestans were regionally distributed in Europe, with populations in western Europe being dominated by clonal lineages and those in northern Europe being genetically diverse because of frequent sexual reproduction. However, since 2013 a new clonal lineage (EU_41_A2) has successfully established itself and expanded in the sexually recombining P. infestans populations of northern Europe. The objective of this study was to study phenotypic traits of the new clonal lineage of P. infestans, which may explain its successful establishment and expansion within sexually recombining populations. Fungicide sensitivity, aggressiveness, and virulence profiles of isolates of EU_41_A2 were analyzed and compared with those of the local sexual populations from Denmark, Norway, and Estonia. None of the phenotypic data obtained from the isolates collected from Denmark, Estonia, and Norway independently explained the invasive success of EU_41_A2 within sexual Nordic populations. Therefore, we hypothesize that the expansion of this new genotype could result from a combination of fitness traits and more favorable environmental conditions that have emerged in response to climate change.

How optical excitation controls the structure and properties of vanadium dioxide.

We combine ultrafast electron diffraction and time-resolved terahertz spectroscopy measurements to link structure and electronic transport properties during the photoinduced insulator-metal transitions in vanadium dioxide. We determine the structure of the metastable monoclinic metal phase, which exhibits antiferroelectric charge order arising from a thermally activated, orbital-selective phase transition in the electron system. The relative contribution of the photoinduced monoclinic and rutile metals to the time-dependent and pump-fluence-dependent multiphase character of the film is established, as is the respective impact of these two distinct phase transitions on the observed changes in terahertz conductivity. Our results represent an important example of how light can control the properties of strongly correlated materials and demonstrate that multimodal experiments are essential when seeking a detailed connection between ultrafast changes in optical-electronic properties and lattice structure.

Evaluating the Test Validity of the Comprehensive Assessment of Psychopathic Personality Symptom Rating Sale (CAPP SRS).

The Comprehensive Assessment of Psychopathic Personality Symptom Rating Scale (CAPP SRS) is a relatively new measure of psychopathic personality disorder (PPD) based on the CAPP concept map of psychopathy. To investigate the CAPP SRS, we identified the most plausible formal test structure for the test using the framework proposed by Slaney and Maraun, identified an appropriate quantitative characterization of that test structure, and then statistically evaluated it based on analysis of CAPP SRS data collected from a multisite sample of 314 adult male correctional offenders and secure hospital patients in Scotland and England. Overall, the CAPP SRS survived falsification when observed test data were compared to expectations based on the unidimensional monotone latent variable or UMLV model of Holland and Rosenbaum. CAPP SRS composite scores calculated consistent with the UMLV model had good measurement precision and good external validity with respect to scores on an established test of PPD. The findings provide provisional support for the test validity of the CAPP SRS and highlight the importance of theory-driven evaluations of test validity.

Update on Biometry and Lens Calculation - A Review of the Basic Principles and New Developments. / Update Biometrie und Linsenberechnung ­ ein Review zu Grundlagen und neuen Entwicklungen.

These days, accurate calculation of artificial lenses is an important aspect of patient management. In addition to the classic theoretical optical formulae there are a number of new approaches, most of which are available as online calculators. This review aims to explain the background of artificial lens calculation and provide an update on study results based on the latest calculation approaches. Today, optical biometry provides the computational basis for theoretical optical formulae, ray tracing, and also empirical approaches using artificial intelligence. Manufacturer information on IOL design and IOL power recorded as part of quality control could improve calculations, especially for higher IOL powers. With modern measurement data, there is further potential for improvement in the determination of the axial length to the retinal pigment epithelium and by adopting a sum-of-segment approach. With the available data, the cornea can be assumed to be a thick lens. The Kane formula, the EVO 2.0 formula, the Castrop formula, the PEARL-DGS, formula and the OKULIX calculation software provide consistently good results for artificial lens calculations. Excellent refractive results can be achieved using these tools, with approximately 80% having an absolute prediction error within 0.50 dpt, at least in highly selected study populations. The Barrett Universal II formula also produces excellent results in the normal and long axial length range. For eyes with short axial lengths, the use of Barrett Universal II should be reconsidered; in this case, one of the methods mentioned above is preferable. Second Eye Refinement can also be considered in this patient population, in conjunction with established classic third generation formulae.

Biometry and Intraocular Lens Power Calculation in Eyes with Prior Laser Vision Correction (LVC) - A Review.

BACKGROUND: An intraocular lens (IOL) calculation in eyes that have undergone laser vision correction (LVC) poses a significant clinical issue in regards to both patient expectation and accuracy. This review aims to describe the pitfalls of IOL power calculation after LVC and give an overview of the current methods of IOL power calculation after LVC. REVIEW: Problems after LVC derive from the measurement of anterior corneal radii, central corneal thickness, asphericity, and the predicted effective lens position. A central issue is that most conventional 3rd generation formulas estimate lens position amongst other parameters on keratometry, which is altered in post-LVC eyes. CONCLUSION: An IOL power calculation results in eyes with prior LVC that are notably impaired in eyes without prior surgery. Effective corneal power including anterior corneal curvature, posterior corneal curvature, CCT (central corneal thickness), and asphericity is essential. Total keratometry in combination with the Barrett True-K, EVO (emmetropia verifiying optical formula), or Haigis formula is relatively uncomplicated and seems to provide good results, as does the Barrett True-K formula with anterior K values. The ASCRS ( American Society of Cataract and Refractive Surgery) calculator combines results of various formulae and averages results, which allows a direct comparison between the different methods. Tomography-based raytracing and the Kane and the Castrop formulae need to be evaluated by future studies.

Readmission After Lobectomy for Lung Cancer: Not All Complications Contribute Equally.

OBJECTIVE: The aim of this study was to identify independent predictors of hospital readmission for patients undergoing lobectomy for lung cancer. SUMMARY BACKGROUND DATA: Hospital readmission after lobectomy is associated with increased mortality. Greater than 80% of the variability associated with readmission after surgery is at the patient level. This underscores the importance of using a data source that includes detailed clinical information. METHODS: Using the Society of Thoracic Surgeons (STS) General Thoracic Surgery Database (GTSD), we conducted a retrospective cohort study of patients undergoing elective lobectomy for lung cancer. Three separate multivariable logistic regression models were generated: the first included preoperative variables, the second added intraoperative variables, and the third added postoperative variables. The c statistic was calculated for each model. RESULTS: There were 39,734 patients from 277 centers. The 30-day readmission rate was 8.2% (n = 3237). In the final model, postoperative complications had the greatest effect on readmission. Pulmonary embolus {odds ratio [OR] 12.34 [95% confidence interval (CI),7.94-19.18]} and empyema, [OR 11.66 (95% CI, 7.31-18.63)] were associated with the greatest odds of readmission, followed by pleural effusion [OR 7.52 (95% CI, 6.01-9.41)], pneumothorax [OR 5.08 (95% CI, 4.16-6.20)], central neurologic event [OR 3.67 (95% CI, 2.23-6.04)], pneumonia [OR 3.13 (95% CI, 2.43-4.05)], and myocardial infarction [OR 3.16 (95% CI, 1.71-5.82)]. The c statistic for the final model was 0.736. CONCLUSIONS: Complications are the main driver of readmission after lobectomy for lung cancer. The highest risk was related to postoperative events requiring a procedure or medical therapy necessitating inpatient care.