Kristin N. Kelly

Perceptual relearning of complex visual motion after V1 damage in humans

Damage to the adult, primary visual cortex (V1) causes severe visual impairment that was previously thought to be permanent, yet several visual pathways survive V1 damage, mediating residual, often unconscious functions known as “blindsight.” Because some of these pathways normally mediate complex visual motion perception, we asked whether specific training in the blind field could improve not just simple but also complex visual motion discriminations in humans with long-standing V1 damage. Global direction discrimination training was administered to the blind field of five adults with unilateral cortical blindness. Training returned direction integration thresholds to normal at the trained locations. Although retinotopically localized to trained locations, training effects transferred to multiple stimulus and task conditions, improving the detection of luminance increments, contrast sensitivity for drifting gratings, and the extraction of motion signal from noise. Thus, perceptual relearning of complex visual motion processing is possible without an intact V1 but only when specific training is administered in the blind field. These findings indicate a much greater capacity for adult visual plasticity after V1 damage than previously thought. Most likely, basic mechanisms of visual learning must operate quite effectively in extrastriate visual cortex, providing new hope and direction for the development of principled rehabilitation strategies to treat visual deficits resulting from permanent visual cortical damage.

Resident involvement is associated with worse outcomes after major lower extremity amputation

BACKGROUND Despite the recent major changes in vascular and general surgery training, there has been a paucity of literature examining the effect of these changes on training and surgical outcomes. Amputations represent a common cross-section in core competencies for general surgery and vascular surgery trainees. This study evaluates the effect of trainee participation on outcomes after above-knee and below-knee amputations. METHODS The American College of Surgeons-National Surgical Quality Improvement Program (NSQIP) database (2005 to 2010) was queried using Current Procedural Terminology codes (American Medical Association, Chicago, Ill) for below-knee amputation (27880, 27882) and above knee-amputation (27590, 27592). Resident involvement was defined using the NSQIP variable and was narrowed to postgraduate year 1 to 5. Variables associated with resident involvement were identified, and mortality, morbidity, intraoperative transfusion, and operative time (75th percentile vs the bottom three quartiles) were evaluated as distinct categoric end points in logistic regression. Included in the model were variables with a P value <.1 on χ(2) or independent t-test, as appropriate. Significance was defined at P < .05. RESULTS Residents were involved in 6587 of 11,038 amputations (62%). After adjustment for preoperative and intraoperative factors on logistic regression, there was a significant increase in major morbidity (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.14-1.42; P < .001), intraoperative transfusion (OR, 1.78; 95% CI, 1.50-2.11; P < .001), and operative time (OR, 1.64 95% CI, 1.46-1.84; P < .001) in resident cases. CONCLUSIONS Resident involvement was associated with increased odds of major morbidity after amputation and also with increased operative time and risk for intraoperative transfusions.

Parastomal Hernia: A Growing Problem with New Solutions

Parastomal hernia is one of the most common complications following stoma creation and its prevalence is only expected to increase. It often leads to a decrease in the quality of life for patients due to discomfort, pain, frequent ostomy appliance leakage, or peristomal skin irritation and can result in significantly increased healthcare costs. Surgical technique for parastomal hernia repair has evolved significantly over the past two decades with the introduction of new types of mesh and laparoscopic procedures. The use of prophylactic mesh in high-risk patients at the time of stoma creation has gained attention in lieu of several promising studies that have emerged in the recent days. This review will attempt to demonstrate the burden that parastomal hernias present to patients, surgeons, and the healthcare system and also provide an overview of the current management and surgical techniques at both preventing and treating parastomal hernias. i 2014 S. Karger AG, Basel

Visually-guided behavior of homonymous hemianopes in a naturalistic task

The gaze behavior of homonymous hemianopes differs from that of visually intact observers when performing simple laboratory tasks. To test whether such compensatory behavior is also evident during naturalistic tasks, we analyzed the gaze patterns of three long-standing hemianopes and four visually intact controls while they assembled wooden models. No significant differences in task performance, saccade dynamics or spatial distribution of gaze were observed. Hemianopes made more look-ahead fixations than controls and their gaze sequences were less predictable. Thus hemianopes displayed none of the compensatory gaze strategies seen in laboratory tasks. Instead, their gaze patterns suggest greater updating of, and greater reliance on a spatial representation.

Risk score for unplanned vascular readmissions

OBJECTIVE Vascular surgery patients have high readmission rates, and identification of high-risk groups that may be amenable to targeted interventions is an important strategy for readmission prevention. This study aimed to determine predictors of unplanned readmission and develop a risk score for predicting readmissions after vascular surgery. METHODS The National Surgical Quality Improvement Program database for 2011 was queried for major vascular surgical procedures. The primary end point was unplanned 30-day readmissions. The data were randomly split into two-thirds for development and one-third for validation. Multivariable logistic regression was used to create and validate a point score system to predict unplanned readmissions. RESULTS Overall, 24,929 patients were included, with 2507 readmissions (10.1%). A point-based scoring system was developed with the use of factors predictive for readmission, including procedure type; discharge destination; race; non-elective presentation; pulmonary, renal, and cardiac comorbidities; diabetes; steroid use; hypoalbuminemia; anemia; venothromboembolism before discharge; graft failure before discharge; and bleeding disorder. The point score stratified patients into 3 groups: low risk (0-3 points) with a readmission rate of 5.4%, moderate risk (4-7 points) with a readmission rate of 8.6%, and high risk (≥ 8 points) with a readmission rate of 16.4%. The model had a C-statistic = 0.67. CONCLUSIONS Through the use of patient, operative, and predischarge events, this novel vascular surgery-specific readmission score accurately identified patients at high risk for 30-day unplanned readmission. This model could help direct discharge and home health care resources to patients at high risk, ultimately reducing readmissions and improving efficiency.

Risk scoring can predict readmission after endocrine surgery

BACKGROUND Hospitals and surgeons simultaneously are pressured to decrease readmissions and duration of stay. We hypothesized that readmissions after endocrine surgery could be predicted by using a novel risk-score. METHODS The National Surgical Quality Improvement Program database was queried for cervical endocrine operations performed during 2011 and 2012. The primary end point was unplanned readmission within 30 days. Multivariable logistic regression was used to create and validate a scoring system to predict unplanned readmissions. RESULTS Overall, 34,046 cases were included with a readmission rate of 2.8% (n = 947). The most frequent reasons for readmission were hypocalcemia (32.4%) surgical-site infection (8.4%), and hematoma (8.0%) (2012 data only). The readmission risk score was created using the following factors: thyroid malignancy, hypoalbuminemia, renal insufficiency, American Society of Anesthesiologists class, and duration of stay >1 day. Predicted readmission rate by number of risk factors was 1.7 % for 0 risk factors, 3.2% for 1 risk factor (5-11 points), 5.8% for 2 risk factors, 10.5% for 3 risk factors, and 18.0% for 4 risk factors. The model had good predictive ability with c = 0.646. CONCLUSION Readmissions after cervical endocrine operations can be predicted. This risk score could be used to direct resource use for preoperative, inpatient, and outpatient care delivery to reduce readmissions.

Perioperative pleiotropic statin effects in general surgery

BACKGROUND Evidence suggests that statins may decrease inflammation, airway hyperreactivity, and hypercoagulability while improving revascularization mediated by cholesterol-independent pathways. This study evaluated whether the preoperative use of statins is associated with decreased postoperative major noncardiac complications in noncardiac procedures. STUDY DESIGN This was a single-institution study of noncardiac operations performed from 2005 to 2010. The use of statins was identified from electronic medical records and merged with local National Surgical Quality Improvement Program data. Preoperative statin exposure was defined as statin use before operation, as documented by admission medication reconciliation and outpatient or pharmacy records. The primary end point was major noncardiac complications, and secondary end points included respiratory, infectious (sepsis and organ space infection) and complications of venous thromboembolism (VTE). Multivariable logistic regression was performed for each end point while we controlled for clinical covariates meeting P < .10 on bivariate analysis. RESULTS Preoperative statin use was present in 10.5% (n = 814) of 7,777 total cases. Procedure type included general operation (n = 2,605, 33.5%), breast/endocrine (n = 739, 9.5%), colorectal (n = 1,533, 19.7%), hepatobiliary/pancreatic (n = 397, 5.1%), orthopedic (n = 205, 2.6%), skin/ear-nose- throat (145, 1.9%), thoracic (n = 53, 0.7%), upper gastrointestinal (n = 651, 8.4%), and vascular cases (1,449, 18.6%). On multivariable analysis, the use of statins was associated with decreased major, noncardiac complications (odds ratio [OR] 0.62, 95% confidence interval [95% CI] 0.49-0.92, P < .001), respiratory complications (OR 0.63, 95% CI 0.50-0.79, P = .017), VTE (OR 0.41, 95% CI 0.18-0.98, P = .044), and infectious complications (OR 0.65, 95% CI 0.45-0.94, P = .023). CONCLUSION The preoperative use of statins is independently associated with decreased risk of major complications. This effect is likely driven by reduction in respiratory, VTE, and infectious complication rates. These results warrant future clinical trials to assess the perioperative benefit of statin use in noncardiac procedures.

Disease severity, not operative approach, drives organ space infection after pediatric appendectomy.

Objective:This study examines patient and operative factors associated with organ space infection (OSI) in children after appendectomy, specifically focusing on the role of operative approach. Background:Although controversy exists regarding the risk of increased postoperative intra-abdominal infections after laparoscopic appendectomy, this approach has been largely adopted in the treatment of pediatric acute appendicitis. Methods:Children aged 2 to 18 years undergoing open or laparoscopic appendectomy for acute appendicitis were selected from the 2012 American College of Surgeons Pediatric National Surgical Quality Improvement Program database. Univariate analysis compared patient and operative characteristics with 30-day OSI and incisional complication rates. Factors with a P value of less than 0.1 and clinical importance were included in the multivariable logistic regression models. A P value less than 0.05 was considered significant. Results:For 5097 children undergoing appendectomy, 4514 surgical procedures (88.6%) were performed laparoscopically. OSI occurred in 155 children (3%), with half of these infections developing postdischarge. Significant predictors for OSI included complicated appendicitis, preoperative sepsis, wound class III/IV, and longer operative time. Although 5.2% of patients undergoing open surgery developed OSI (odds ratio = 1.82; 95% confidence interval, 1.21–2.76; P = 0.004), operative approach was not associated with increased relative odds of OSI (odds ratio = 0.99; confidence interval, 0.64–1.55; P = 0.970) after adjustment for other risk factors. Overall, the model had excellent predictive ability (c-statistic = 0.837). Conclusions:This model suggests that disease severity, not operative approach, as previously suggested, drives OSI development in children. Although 88% of appendectomies in this population were performed laparoscopically, these findings support utilization of the surgeons preferred surgical technique and may help guide postoperative counsel in high-risk children.

Visceral obesity, not elevated BMI, is strongly associated with incisional hernia after colorectal surgery.

BACKGROUND: High BMI is often used as a proxy for obesity and has been considered a risk factor for the development of an incisional hernia after abdominal surgery. However, BMI does not accurately reflect fat distribution. OBJECTIVE: The purpose of this work was to investigate the relationship among different obesity measurements and the risk of incisional hernia. DESIGN: This was a retrospective cohort study. SETTINGS: The study included a single academic institution in New York from 2003 to 2010. PATIENTS: The study consists of 193 patients who underwent colorectal cancer resection. MAIN OUTCOME MEASURES: Preoperative CT scans were used to measure visceral fat volume, subcutaneous fat volume, total fat volume, and waist circumference. A diagnosis of incisional hernia was made either through physical examination in medical chart documentation or CT scan. RESULTS: Forty-one patients (21.2%) developed an incisional hernia. The median time to hernia was 12.4 months. After adjusting for patient and surgical characteristics using Cox regression analysis, visceral obesity (HR 2.04, 95% CI 1.07–3.91) and history of an inguinal hernia (HR 2.40, 95% CI 1.09–5.25) were significant risk factors for incisional hernia. Laparoscopic resection using a transverse extraction site led to a >75% reduction in the risk of incisional hernia (HR 0.23, 95% CI 0.07–0.76). BMI > 30 kg/m2 was not significantly associated with incisional hernia development. LIMITATIONS: Limitations include the retrospective design without standardized follow-up to detect hernias and the small sample size attributed to inadequate or unavailable CT scans. CONCLUSIONS: Visceral obesity, history of inguinal hernia, and location of specimen extraction site are significantly associated with the development of an incisional hernia, whereas BMI is poorly associated with hernia development. These findings suggest that a lateral transverse location is the incision site of choice and that new strategies, such as prophylactic mesh placement, should be considered in viscerally obese patients.

Readmissions After Colectomy: The Upstate New York Surgical Quality Initiative Experience.

BACKGROUND: Hospital readmissions remain a major medical and financial concern to the healthcare system and have become an area of interest in health outcomes performance metrics. There is a pressing need to identify process measures that may help reduce readmissions. OBJECTIVE: Our aim was to assess the patient characteristics and surgical factors associated with 30-day readmissions for colorectal surgery in Upstate New York. DESIGN: This was a retrospective cohort study. SETTINGS: The study included colectomy cases abstracted for the National Surgical Quality Improvement Program in the Upstate New York Surgical Quality Initiative from June 2013 to June 2014. PATIENTS: The study consists of 630 colectomies. Patients with a length of stay >30 days or who died during the index admission were excluded. MAIN OUTCOME MEASURES: Readmission within 30 days of surgery was the main outcome measure. RESULTS: Of 630 colectomy patients, 76 patients (12%) were readmitted within 30 days of surgery. Major and minor complications were associated with 30-day postoperative readmission (OR = 2.99 (95% CI, 1.70–5.28) and OR = 2.19 (95% CI, 1.09–4.43)) but excluded from final analysis because they included both predischarge and postdischarge complications. Risk factors independently associated with 30-day postoperative readmission included diabetes mellitus (OR = 1.94 (95% CI, 1.02–3.67)), smoker within the past year (OR = 2.01 (95% CI, 1.12–3.60)), no scheduled follow-up (OR = 2.20 (95% CI, 1.25–3.86)), and ileostomy formation (OR = 1.97 (95% CI, 1.03–3.77)). LIMITATIONS: Limitations include the retrospective design and only 30 days of postoperative follow-up. CONCLUSIONS: Consistent with national trends, 1 in 8 patients in the Upstate New York Surgical Quality Initiative program was readmitted within 30 days after colorectal surgery. This study identified several risk factors that may act as tangible targets for intervention, including preoperative smoking cessation programs, optimization of diabetic management, mandatory scheduled follow-up appointments on discharge, and ostomy care pathways.