Optimal Timing Of Surgery Research Articles

Optimal timing of surgery in infants with prenatally diagnosed isolated left-sided congenital diaphragmatic hernia: a multicenter, cohort study in Japan.

To date, there is no compelling evidence of the optimal timing of surgery for congenital diaphragmatic hernia (CDH). This study aimed to establish the optimal timing of surgery in neonates with isolated left-sided CDH. This multicenter cohort study enrolled 276 patients with isolated left-sided CDH at 15 institutions. Based on the timing of surgery, the patients were classified into four groups [< 24h (G1), 24-47h (G2), 48-71h (G3), and ≥ 72h (G4)]. The clinical outcomes were compared among the groups using a logistic regression model, after adjusting for potential confounders, such as disease severity. Multivariate analyses showed that G2 also had a lower mortality rate than the other groups. In mild and severe cases, there were no significant differences in mortality across the four groups. In moderate cases, G2 resulted in significantly increased survival rates, compared with G1. The study results suggest that surgery within 24h of birth is not recommended for patients with moderate severity CDH, that there is no benefit in the delay of surgery for more than 72h in mild severity CDH patients, and that there is no definite optimal time to perform surgery in severe cases of CDH.

An electrophysiological biomarker for the classification of cataract-reversal patients: A case-control study.

BackgroundUntreated congenital blindness through cataracts leads to lasting visual brain system changes, including substantial alterations of extrastriate visual areas. Consequently, late-treated individuals (> 5 months of age) with dense congenital bilateral cataracts (CC) exhibit poorer visual function recovery compared to individuals with bilateral developmental cataracts (DC). Reliable methods to differentiate between patients with congenital and developmental cataracts are often lacking, impeding efficient rehabilitation management and introducing confounds in clinical and basic research on recovery prognosis and optimal timing of surgery. A persistent reduction of the P1 wave of visual event-related potentials (VERPs), associated with extrastriate visual cortical activity, has been reported in CC but not in DC individuals. Using two experiments, this study developed and validated P1-based biomarkers for diagnosing a history of congenital blindness in cataract-reversal individuals.MethodsCongenital and developmental cataract-reversal individuals as well as typically sighted matched controls took part in a first experiment used for exploring an electrophysiological biomarker (NCC = 13, NDC = 13, NControl = 26). Circular stimuli containing gratings were presented in one of the visual field quadrants while visual event-related potentials (VERPs) were recorded. Two biomarkers were derived from the P1 wave of the VERP: (1) The mean of the normalized P1 amplitude at posterior electrodes, and (2) a classifier obtained from a linear support vector machine (SVM). A second experiment with partially new CC/DC individuals and their matched controls (NCC = 14, NDC = 15, NControl = 29) was consecutively used to validate the classification based on both biomarkers. Performance of the classifiers were evaluated using receiver operating characteristic (ROC) curve analyses. All cataract-reversal individuals were tested after at least one year of vision recovery.FindingsThe normalized P1 amplitude over posterior electrodes allowed a successful classification of the CC from the DC individuals and typically sighted controls (area under ROC curve, AUC = 0.803 and 0.929 for the normalized P1 amplitude and the SVM-based biomarker, respectively). The validation for both biomarkers in experiment 2 again resulted in a high classification success (AUC = 0.800 and 0.883, respectively for the normalized P1 amplitude and the SVM-based biomarker). In the most conservative scenario involving classification of CC from DC individuals in a group of only cataract-reversal individuals, excluding typically sighted controls, the SVM-based biomarker was found to be superior to the mean P1 amplitude based biomarker (AUC = 0.852 compared to 0.757 for the mean P1 based biomarker in validation). Minimum specificity obtained was 80% across all biomarkers.InterpretationA persistent reduction of the P1 wave provides a highly specific method for classifying cataract patients post-surgically as having suffered from bilateral congenital vs. bilateral developmental cataracts. We suggest that using the P1 based non-invasive electrophysiological biomarker will augment existing clinical classification criteria for individuals with a history of bilateral congenital cataracts, aiding clinical and basic research, recovery prognosis, and rehabilitation efforts.FundingGerman Research Foundation (DFG) and the European Research Council (ERC).

The surgical repair of proximal hamstring avulsions.

Despite the increase in the surgical repair of proximal hamstring tears, there exists a lack of consensus in the optimal timing for surgery. There is also disagreement on how partial tears managed surgically compare with complete tears repaired surgically. This study aims to compare the mid-term functional outcomes in, and operating time required for, complete and partial proximal hamstring avulsions, that are repaired both acutely and chronically. This is a prospective series of 156 proximal hamstring surgical repairs, with a mean age of 48.9 years (21.5 to 78). Functional outcomes were assessed preinjury, preoperatively, and postoperatively (six months and minimum three years) using the Sydney Hamstring Origin Rupture Evaluation (SHORE) score. Operating time was recorded for every patient. Overall, significant improvements in SHORE scores were seen at both six months and mid-term follow-up. Preoperatively, acute patients (median score 27.1 (interquartile range (IQR) 22.9)) reported significantly poorer SHORE scores than chronic patients (median score 42.9 (IQR 22.1); p < 0.001). However, this difference was not maintained postoperatively. For partial tears, acutely repaired patients reported significantly lower preoperative SHORE scores compared to chronically reapired partial tears (median score 24.3 (IQR 15.7) vs median score 40.0 (IQR 25.0); p < 0.001) but also significantly higher SHORE scores at six-month follow-up compared to chronically repaired partial tears (median score 92.9 (IQR 10.7) vs. median score 82.9 (IQR 14.3); p < 0.001). For complete tears, there was only a difference in preoperative SHORE scores between acute and chronic groups. Overall, acute repairs had a significantly shorter operating time (mean 64.67 minutes (standard deviation (SD) 12.99)) compared to chronic repairs (mean 74.71 minutes (SD = 12.0); t = 5.12, p < 0.001). Surgical repair of proximal hamstring avulsions successfully improves patient reported functional outcomes in the majority of patients, irrespective of the timing of their surgery or injury classification. However, reducing the time from injury to surgery is associated with greater improvement in patient outcomes and an increased likelihood of returning to preinjury functional status. Acute repair appears to be a technically less complex procedure, as indicated by reduced operating times, postoperative neurological symptoms and number of patients requiring bracing. Acute repair is therefore a preference among many surgeons. Cite this article: Bone Joint J 2020;102-B(10):1419-1427.

Sub-clinical Detection of Left Ventricular Myocardial Dysfunction in Valvular Heart Diseases: A State-of-the-Art Review in a Speckle Tracking Echocardiography and Myocardial Performance

Purpose of the state-of-the-art review: Left ventricular (LV) global longitudinal strain (GLS) is recently recognized as a more sensitive measure of LV myocardial systolic function compared with LV ejection fraction (LVEF). In addition, left ventricular GLS , myocardial performance index (MPI) and maximum rate of LV pressure rise during isovolumetric contraction (LV dP/dtmax) are more reproducible than traditional assessment of LV systolic function by two dimensional echocardiography (2DE) LVEF. These underutilized techniques can detect preclinical myocardial dysfunction in patients who are at risk of LV failure in valvular-induced heart disease . Current guidelines for diagnosis and treatment of valvular heart disease (VHD) include LVEF as one of the parameters to take into consideration in the clinical decision-making. However, a large body of evidence has shown that left ventricular GLS, MPI and LV dP/dtmax have been classically considered as a sensitive marker of LV contractility and inotropic state. In turn GLS and myocardial performance may be a better prognosticator than LVEF in aortic and mitral valve heart diseases. This timely state-of-the-art review, appraised the evidence and role of GLS, MPI and dP/dT as clinical tools in patients with aortic and mitral valve disease. Recent findings: Left ventricular GLS has been shown to be prognostic in low-flow, low-gradient severe aortic stenosis with preserved LVEF. The role of left ventricular GLS, Tei index (MPI) and maximum rate of LV pressure rise (LV dP/dtmax) in patients with aortic regurgitation and mitral valve diseases (regurgitation and stenosis) is less well established. Summary: Echocardiography is considered the primary non-invasive imaging tool for valvular heart disease assessment and the cornerstone method in diagnosing and evaluating the morphology and severity of aortic and mitral valve diseases. Currently, diagnostic-cardiac catheterization is no more recommended except in very rare cases when echocardiographic image quality is suboptimal, non-diagnostic and when the results of 2DE are discrepant with clinical data. Once clinical decision-making is based on the 2DE and three dimensional echocardiographic in assessment of the severity of mitral and aortic valve diseases, it is crucial that standards should be adopted to maintain accuracy and consistency across echocardiographic laboratories. This illustrative review article assesses left ventricular systolic function (LVEF) employing two and/or three dimensional echocardiography in comparison to GLS, MPI and LV dP/dtmax, especially applied for aortic valve (AV) and mitral valve (MV) diseases. It is noteworthy that this document only provides echocardiographic standards rather than making recommendations for clinical management. Conclusion: It is concluded that GLS, MPI and maximum rate of LV pressure rise during isovolumetric contraction (LV dP/dtmax) are recommended and more so, they should be increasingly used to identify subclinical LV myocardial dysfunction in patients with mitral and aortic valve heart diseases, to identify optimal timing for surgery and prognosticate outcomes after surgery

Time to surgery: Is it truly crucial in initially stable patients with penetrating injury?

BackgroundTreatment recommendations for patients with penetrating abdominal injury are well established. Trauma victims with clear indications for surgery, should undergo immediate operative intervention without any delay or additional imaging. However, the optimal time for surgery remains unclear. There are some significant advantages in preoperative abdominal CT, including gathering essential information regarding a few difficult to reach anatomical areas, avoiding unnecessary explorations associated with increased morbidity and assessing the existence of extra-abdominal injuries that may have non-expectable impact on initial therapeutic plan. The aim of this study was to determine the impact of "time-to-surgery" on final medical outcomes in patients with penetrating abdominal trauma with normal blood pressure on admission. MethodsA retrospective cohort study using the Israeli National Trauma Registry was conducted from 2000- 2018. This study included trauma patients with penetrating injuries and a systolic blood pressure of 90mmHg or above on admission. All patients included in the study were divided into three groups according to the time that lapsed from their admission to surgery: half an hour, an hour, and two hours. We assessed the outcome for each patient, including length of hospital stay, need for intensive care and mortality. Statistical analysis was performed using the Chi-square test, ANOVA test. A p-value of less than 0.05 was considered statistically significant. ResultsThe study included 1,136 penetrating trauma patients. Among these, 78.0% (886) had sustained low-energy penetrating injury (SWPI) and 22.0% (250) had sustained high-energy penetrating injury (FAPI). Males accounted for 93.5% (1,062) of the patients. Mean age was 30.4. About 29% (327) of all the patients underwent surgery within 30 minutes from admission, 42% (475) within 30-60 min, and 29% (334) patients were operated within one to two hours. Patients who underwent surgery within 30 minutes, had worse ISS and GCS scores and were, therefore, more likely to have worse clinical outcomes. No other differences in outcomes were found in patients who were operated upon within 2 hours. ConclusionsTime to surgery within two hours from admission has no impact on final outcomes in trauma patients with penetrating injury and normal blood pressure on admission.

From the completion of neoadjuvant chemotherapy to surgery for colorectal cancer liver metastasis: What is the optimal timing?

BackgroundNeoadjuvant chemotherapy (NAC) has been widely performed in the treatment of colorectal cancer liver metastasis (CRLM) patients, but the optimal timing of surgery after NAC is unclear. The aim of this study was to investigate the optimal timing of surgery.MethodsFrom December 2010 to May 2018, 101 consecutive patients who received NAC followed by liver resection for CRLM were included in this study. The main outcome parameters were pathological response, progression‐free survival (PFS), and overall survival (OS). The effect of time to surgery (TTS) on patient outcomes, defined as a high TTS and a low TTS according to an X‐tile analysis, was investigated. To adjust for potential selection bias, propensity score matching at 1:2 was performed with two high TTS patients matched to one low TTS patient. Kaplan‐Meier curves, logistic regression analyses, and Cox regression models were used for the data analysis.ResultsThe optimal cut‐off value for the TTS was 5 weeks by X‐tile analysis. The patients in this study were divided into low (≤5 weeks, n = 27) and high (>5 weeks, n = 74) TTS groups. Patients with a high TTS were more likely to have an unfavorable pathological response (75.7% vs 48.1%, P = .008). In multivariate analysis, a low TTS significantly predicted a better pathological response (OR = 3.397, 95% CI: 1.116‐10.344, P = .031). Compared to patients with a high TTS, patients with a low TTS had significantly better PFS (P < .001, mPFS: 16 months vs 7 months) and better OS (P = .037, mOS: not reached vs 36 months). Multivariate analysis revealed that a TTS > 5 weeks was an independent predictor of decreased PFS (HR = 2.041, 95% CI: 1.152‐3.616, P = .014) but not OS. After propensity matching, the patients with a low TTS had significantly better PFS (P < .001, mPFS: 18.2 months vs 10 months) and an equivalent OS (P = .115, mOS: not reached vs 41 months). Multivariate analysis revealed that a TTS > 5 weeks was an independent predictor of decreased PFS (HR = 3.031, 95% CI: 1.494‐6.149, P = .002) but not OS.ConclusionThe longer TTS after the completion of NAC may be disadvantageous for a favorable pathological response and long‐term PFS. These results should be validated prospectively in a randomized trial.

The Indications for and Timing of Surgery for Diverticular Disease.

Diverticular disease is one of the more common abdominal disorders. In 2016, approximately 130 000 patients received inpatient treatment for diverticular disease in Germany. The disease has a number of subtypes, each of which has an appropriate treatment. In this article, we present the current surgical indications and optimal timing of surgery for diverticular disease. This review is based on publications that were retrieved by an extensive, selective search in Medline and the Cochrane Library (1998-2018) for studies and guidelines with information on the indications for surgery in diverticular disease. Studies of evidence grades 2 to 4 were available. Patients receiving a diagnosis of freely perforated diverticulitis and peritonitis (Classification of Diverticular Disease [CDD] type 2c) should be operated on at once. Covered perforated diverticulitis with a macroabscess (>1 cm, CDD type 2b) may be an indication for elective surgery after successful conservative treatment. New evidence from a randomized, controlled trial suggests that elective surgery should also be considered for patients with chronic recurrent diverticulitis (CDD type 3b). The decisive factor in such cases is the impairment of the quality of life for the individual patient. Elective surgery is indicated in chronic recurrent diverticulitis with complications (fistulae, stenoses). Asymptomatic diverticulosis (CDD type 0) and uncomplicated diverticulitis (CDD type 1) are not surgical indications. Likewise, in diverticular hemorrhage (CDD type 4), surgery is only indicated in exceptional cases, when conservative treatment fails. The surgical indication and the proper timing of surgery depend on the type of disease that is present. Future studies should more thoroughly investigate the effect of surgery on the quality of life in patients with the various types of diverticular disease.

Impact of interval between neoadjuvant chemoradiotherapy and surgery in rectal cancer patients.

BACKGROUNDEpidemiologically, in China, locally advanced rectal cancer is a more common form of rectal cancer. Preoperative neoadjuvant concurrent chemoradiotherapy can effectively reduce the size of locally invasive tumors and improve disease-free survival (DFS) and pathologic response after surgery. At present, this modality has become the standard protocol for the treatment of locally advanced rectal cancer in many centers, but the optimal time for surgery after neoadjuvant therapy is still controversial.AIMTo investigate the impact of time interval between neoadjuvant therapy and surgery on DFS and pathologic response in patients with locally advanced rectal cancer.METHODSA total of 231 patients who were classified as having clinical stage II or III advanced rectal cancer and underwent neoadjuvant chemoradiation followed by surgery at the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from November 2014 to August 2017 were involved in this retrospective cohort study. The patients were divided into two groups based on the different time intervals between neoadjuvant therapy and surgery: 139 (60.2%) patients were in group A (≤ 9 wk), and 92 (39.2%) patients were in group B (> 9 wk). DFS and pathologic response were analyzed as the primary endpoints. The secondary endpoints were postoperative complications and sphincter preservation.RESULTSFor the 231 patients included, surgery was performed at ≤ 9 wk in 139 (60.2%) patients and at > 9 wk in 92 (39.8%). The patients’ clinical characteristics, surgical results, and tumor outcomes were analyzed through univariate analysis combined with multivariate regression analysis. The overall pathologic complete response (pCR) rate was 27.2% (n = 25) in the longer time interval group (> 9 wk) and 10.8% (n = 15) in the shorter time interval group (≤ 9 wk, P = 0.001). The postoperative complications did not differ between the groups (group A, 5% vs group B, 5.4%; P = 0.894). Surgical procedures for sphincter preservation were performed in 113 (48.9%) patients, which were not significantly different between the groups (group A, 52.5% vs group B, 43.5%; P = 0.179). The pCR rate was an independent factor affected by time interval (P = 0.009; odds ratio [OR] = 2.668; 95%CI: 1.276-5.578). Kaplan-Meier analysis and Cox regression analysis showed that the longer time interval (> 9 wk) was a significant independent prognostic factor for DFS (P = 0.032; OR = 2.295; 95%CI: 1.074-4.905), but the time interval was not an independent prognostic factor for overall survival (P > 0.05).CONCLUSIONA longer time interval to surgery after neoadjuvant therapy may improve the pCR rate and DFS but has little impact on postoperative complications and sphincter preservation.

Early surgical correction of mitral valve infection endocarditis in 16-year old female patient

The optimal time for surgery on the heart valves in patients with active infectious endocarditis (IE) is still controversial. It is a well known fact that cerebral, coronary or renal thromboembolism is the most common cause of death in patients with left-sided IE. Thromboembolism can develop before the appearance of clinical manifestations of the destruction of the valvular apparatus of the heart. Currently, early surgical intervention is considered as the most effective method of treatment of many forms of active left-sided IE. Early surgery involves performing surgical correction until the completion of a full antibiotics course. We present the clinical case of early surgical correction of the patient (A., 16 years) with mitral valve infectious endocarditis. The disease was acute, with recurrent embolisms to the right kidney with infarction and to the left clavicle with osteomyelitis. Surgical intervention was performed as a matter of urgency; surgical access right-sided anterolateral thoracotomy. The girl was operated on the 4th day of the hospitalization to our hospital. However, time of treatment was lost at the prehospital stage and rapid mitral valve destruction did not allow to repair the valve. Therefore, the mitral valve replacement was performed. The postoperative period was favorable. On the 3rd day after the operation, the girl was transferred to the cardiology department. On control ECHO after 3 years: myocardial contractile function is good, EF 65%, the function of the MV prosthesis is not impaired.

Early surgical intervention for unusually located cardiac fibroelastomas

Papillary fibroelastomas are the second most common primary cardiac tumor in adults. Over 80% of fibroelastomas occur on the cardiac valves, usually on the left side of the heart, while the remaining lesions are typically scattered throughout the atria and ventricles. Although the optimal timing for surgery is controversial and depends on tumor size and location, prompt surgical resection is warranted in patients at high risk of embolism. A tumor on the cardiac valve can be removed using the slicing excision technique without leaflet injury. Here we present two cases of papillary fibroelastomas occurring on the ventricular surface of the aortic valve and in the right ventricle.

Trapeziometacarpal Joint Arthritis: Is Duration of Symptoms a Predictor of Surgical Outcomes?

Great effort has been placed on determining the optimal surgical treatment for trapeziometacarpal joint arthritis (TMA). However, a paucity of literature exists concerning the optimal timing of surgical intervention. We hypothesized that an increased duration of TMA symptoms before operative intervention would negatively affect surgical outcomes. We performed a retrospective review on 109 adult patients with 121 joints with symptomatic TMA treated with trapeziectomy and ligament reconstruction with tendon interposition (LRTI) from 2006 to 2017. Outcome measures included Quick-Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, complication rates, and surgical revision rates. Among 109 patients, average QuickDASH score at initial presentation was 41.1 ± 17.9. Patients had symptoms of TMA for an average of 3.2 years (median, 2.1 years) before undergoing operative intervention. Patients were divided into 2 groups: those with symptoms less than 2 years and those with symptoms greater than 2 years. Patients who underwent LRTI after less than 2 years of symptoms achieved a significantly greater degree of improvement in the QuickDASH score compared with patients with symptoms greater than 2 years (26.2 vs 5.3). Patients with less than 2 years of symptomatic TMA before LRTI can expect the greatest improvement in patient-reported disability impairment compared with those with more than 2 years of symptoms. This can be used to counsel patients regarding the optimal timing of surgery if nonsurgical treatment has failed to provide durable symptomatic relief. Therapeutic IV.

Early vs late cardiac surgery in patients with native valve endocarditis-United States Nationwide Inpatient database.

Although the standard treatment of infective endocarditis (IE) is antimicrobial therapy, surgical intervention is required in some cases. However, the optimal timing of surgery remains unclear. Hence, we conducted a population-based analysis using the National Inpatient Sample (NIS) database to assess the outcomes of early versus late surgery in patients with native valve IE. We queried the NIS database for all hospitalized patients between 2006 and 2016 with a primary diagnosis of IE who had cardiac surgery. We stratified surgery as early ≤7 or late >7 days of admission. Multivariable logistic regression models were used to assess in-hospital mortality and postoperative complications. Length of stay (LOS) and total hospital cost (HC) were evaluated using multivariable log-normal regression models. A total of 13 056 patients (57.6% in the early group and 42.4% in the late group) were included. The in-hospital mortality rate in the early group was 5.0% compared to 5.4% in the late intervention group (adjusted odds ratio, 1.20, 95% confidence interval [CI] 0.79-1.81). Overall median LOS was reduced in the early group by 48.2% (95% CI, 46.5%-49.9%, 12.4 days in the early group and 25.9 days in late group), as well as HC which was reduced in the early group by 28.3% (95% CI, 26.0%-30.6%). Among patients with native valve IE who needed cardiac surgery, the time of surgical intervention did not affect the in-hospital mortality. However, early surgery was associated with significantly shorter LOS and lower HC.

Reconstruction of right ventricular outflow tract stenosis and right ventricular failure after Ross procedure \u2013 comprehensive assessment of adult congenital heart disease with four-dimensional imaging: a case report

BackgroundRe-intervention after Ross procedure into the right ventricular outflow tract might be needed in patients in the long term. However, right ventricular outflow tract re-intervention indications are still unclear. Comprehensive assessment of total hemodynamics is needed.Case summaryA 42-year-old Japanese woman was referred to our hospital for moderately severe pulmonary regurgitation and severe tricuspid regurgitation after a Ross–Konno procedure. Thirteen years after surgery, she developed atrial fibrillation and atrial flutter and complained of dyspnea. Electrophysiological studies showed re-entry circuit around the low voltage area of the lateral wall on the right atrium. Four-dimensional flow magnetic resonance imaging revealed moderate pulmonary regurgitation, severe tricuspid regurgitation, and a dilated right ventricle. Flow energy loss in right ventricle calculated from four-dimensional flow magnetic resonance imaging was five times higher than in normal controls, suggesting an overload of the right-sided heart system. Her left ventricular ejection fraction was almost preserved. Moreover, the total left interventricular pressure difference, which shows diastolic function, revealed that her sucking force in left ventricle was preserved. After the comprehensive assessments, we performed right ventricular outflow tract reconstruction, tricuspid valve annuloplasty, and right-side Maze procedure. A permanent pacemaker with a single atrial lead was implanted 14 days postoperatively. She was discharged 27 days postoperatively. Echocardiography performed 3 months later showed that the size of the dilated right ventricle had significantly reduced.DiscussionA four-dimensional imaging tool can be useful in the decision of re-operation in patients with complex adult congenital heart disease. The optimal timing of surgery should be considered comprehensively.

Prophylaxis of Crohn's disease recurrence: A surgeon's perspective.

Management of inflammatory bowel disease has evolved extensively in the last three decades. We have learnt a lot about the pathophysiology and natural history of the disease. New effective classes of drugs with the associated potential morbidity have been introduced. New surgical techniques have been popularized leading to a better understanding of the optimal timing of surgery. The result is a very complex subspecialty of gastroenterology and colorectal surgery called the "IBDologist." Only if we manage these complex patients in the context of a multi‐disciplinary team will we be able to obtain outstanding outcomes, specifically with high and sustained remission rates for these patients.

Estimating the optimal timing of surgery from observational data.

Infants with hypoplastic left heart syndrome require an initial Norwood operation, followed some months later by a stage 2 palliation (S2P). The timing of S2P is critical for the operation's success and the infant's survival, but the optimal timing, if one exists, is unknown. We attempt to identify the optimal timing of S2P by analyzing data from the Single Ventricle Reconstruction Trial (SVRT), which randomized patients between two different types of Norwood procedure. In the SVRT, the timing of the S2P was chosen by the medical team; thus with respect to this exposure, the trial constitutes an observational study, and the analysis must adjust for potential confounding. To accomplish this, we propose an extended propensity score analysis that describes the time to surgery as a function of confounders in a discrete competing-risk model. We then apply inverse probability weighting to estimate a spline hazard model for predicting survival from the time of S2P. Our analysis suggests that S2P conducted at 6 months after the Norwood gives the patient the best post-S2P survival. Thus, we place the optimal time slightly later than a previous analysis in the medical literature that did not account for competing risks of death and hearttransplantation.

Impact of torrefaction on biomass properties depending on temperature and operation time

Torrefaction is an effective way to upgrade biomass for producing fuels. The experimental results of torrefaction for three materials, oak wood, mixed wood mainly from deciduous trees and sewage sludge are presented. The comparison between three materials is performed to evaluate the influence of temperature and time on torrefaction operation. The influence of the operating temperature and time was analysed in order to determine optimal operation parameters for the newly developed process which has been patented. Properties, such as heating value, mass loss, chemical compositions, energy yield and enhancement factor were investigated. The results show that from an energy point of view the optimal operation time for oak and mixed wood is around 1.2 h at 260 °C. The torrefaction of sewage sludge is energetically unjustified. The highest carbon loss is shown for mixed wood, following by sewage sludge and oak wood. Torrefaction severity index was established based on the, most severe conditions. Torrefaction severity index could be applied as an indicator for prediction of torrefaction efficiency of chosen material.

Upstream migration of fishes downstream of an under-construction hydroelectric dam and implications for the operation of fish passage facilities

Fish behavior measurements are important for river and fishery scientists to protect fish resources and for ecological engineers to guide ecosystem conservation but they can pose a practical challenge. In this study, an acoustic camera was used to observe the migration patterns of fish species downstream of an under-construction hydroelectric dam, the Lianghekou dam in the middle Yalong River, China. The fixed-point method was employed to continuously measure fish migration using a dual-frequency identification sonar (DIDSON) during the spawning periods from April to August. The fish number and length measured by sonar were in fairly good agreement with the results of manual counting and field fishing, respectively. The results showed that the number of fish individuals migrating upstream (NFU) and fish length varied monthly and diurnally, and the NFU measured at dark twilight were 2–3 times greater than those measured during the daytime. The analysis showed that the upstream migratory behavior is dominated by the combined actions of river discharge, water temperature, and time of day. Based on the results, we suggest that the suitable operation time for future fish passage facilities could be when the river discharge ranges from 500 m3/s to 1500 m3/s and the water temperature ranges from 13 °C to 16 °C when the fishes in the study area mostly migrated upstream. The optimal operation time could be at night when the river discharge and water temperature are approximately 1000 m3/s and 15 °C, respectively. Although the indirect evidence of fish migration was recorded at a single location, this study reveals the great potential of acoustic cameras for measuring fish migration behavior downstream from hydropower stations which could be helpful for fish passage studies and fish resource conservation in China.

Poor Prognostic Factors for Surgical Treatment of Spinal Intramedullary Ependymoma (World Health Organization Grade II).

Study DesignSingle-center retrospective study.PurposeWe aimed to explore the postoperative prognostic factors for spinal intramedullary ependymoma.Overview of LiteratureEpendymoma (World Health Organization grade II) is the most frequent intramedullary spinal tumor and is treated by total resection. However, postoperative deterioration of motor function occasionally occurs.MethodsEighty patients who underwent surgical resection at Keio University and Fujita Health University in Tokyo, Japan between 2003 and 2015 with more than 2 years of follow-up were enrolled. A good surgical result was defined as an improvement in the modified McCormick Scale score by one grade or more or having the same clinical grade as was observed preoperatively. Meanwhile, a poor result was defined as a reduction in the McCormick Scale score of one grade or more or remaining in grade IV or V at final follow-up. Univariate and multivariate logistic regression analyses of the following factors were performed in the two groups: sex, age, preoperative Visual Analog Scale (VAS), tumor location, the extent of tumor resection, hemosiderin caps, cavity length, and tumor length on magnetic resonance imaging.ResultsAt final follow-up, 15 patients were included in the poor results group and 65 in the good results group. In the univariate analysis, the factors related to poor results were as follows: higher age, preoperative McCormick Scale score severity, higher preoperative VAS, thoracic location, hemosiderin capped, and non-gross total resection (GTR). A multiple logistic regression analysis was conducted and showed that age, worse preoperative McCormick Scale score, and non-GTR were significant factors for poor prognosis.ConclusionsThe independent risk factors for motor deterioration after ependymoma resection were age, worse preoperative McCormick Scale score, and non-GTR. Early surgery for patients with even mild neurological disorders could facilitate functional outcomes. These results may contribute to determining the optimal timing of surgery for spinal intramedullary ependymoma.

Traumatic facial nerve palsy: evaluation and surgical management

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Acute facial paralysis can result from various causes, among which intra temporal facial palsy is relatively common. Of all the cranial nerves, the facial nerve is most susceptible to injury due to its long course within the skull. Diagnosis of facial palsy is usually made by a good clinical history, examination and radiological investigations. Electrophysiological tests are important for prognosis and optimal time for surgery. The aim is to study the evaluation and surgical management in traumatic cause of facial nerve palsy.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; This prospective cross-sectional study was carried out in 50 patients presented with facial nerve palsy due to trauma in civil hospital Ahmedabad over a period of 1 year from May 2018 to 2019. Patients were examined and graded using House and Brackmann grading system. All the patients were evaluated and treated by surgical decompression. Follow up was carried out upto 6 months. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; The cause of facial nerve palsy in all 50 patients was accidental head trauma. All the patients were managed by surgical decompression. 46 out of 50 patients managed surgically had good recovery with restoration of complete facial nerve function. 4 out 50 patients had poor recovery due to late presentation. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Early initiation of treatment is important for favorable recovery of facial nerve function after trauma. Surgical treatment is indicated in suspected bony impingement of nerve. Surgical decompression if done early usually results in very good recovery. &lt;/p&gt;

Management Considerations for the Surgical Treatment of Colorectal Cancer During the Global Covid-19 Pandemic.

Objective:The COVID-19 pandemic requires to conscientiously weigh “timely surgical intervention” for colorectal cancer against efforts to conserve hospital resources and protect patients and health care providers.Summary Background Data:Professional societies provided ad-hoc guidance at the outset of the COVID-19 pandemic on deferral of surgical and perioperative interventions, but these lack specific parameters to determine the optimal timing of surgery.Methods:Using the GRADE system, published evidence was analyzed to generate weighted statements for stage, site, acuity of presentation, and hospital setting to specify when surgery should be pursued, the time and duration of oncologically acceptable delays, and when to utilize nonsurgical modalities to bridge the waiting period.Results:Colorectal cancer surgeries—prioritized as emergency, urgent with imminent emergency or oncologically urgent, or elective—were matched against the phases of the pandemic. Surgery in COVID-19-positive patients must be avoided. Emergent and imminent emergent cases should mostly proceed unless resources are exhausted. Standard practices allow for postponement of elective cases and deferral to nonsurgical modalities of stage II/III rectal and metastatic colorectal cancer. Oncologically urgent cases may be delayed for 6(–12) weeks without jeopardizing oncological outcomes. Outside established principles, administration of nonsurgical modalities is not justified and increases the vulnerability of patients.Conclusions:The COVID-19 pandemic has stressed already limited health care resources and forced rationing, triage, and prioritization of care in general, specifically of surgical interventions. Established guidelines allow for modifications of optimal timing and type of surgery for colorectal cancer during an unrelated pandemic.