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394 citation(s) found for "Iyer, S R".

Obesity and GERD impair esophageal epithelial permeability through 2 distinct mechanisms
Blevins, Christopher H. , Dierkhising, Ross , Geno, Debra M., Johnson, Michele L., Vela, Marcelo F. , Iyer, Prasad G. , Katzka, David A. , Blevins, C H , Ravi, Karthik

Neurogastroenterology & Motility | July 31, 2018 | Volume: 30 | Issue: 10 | Pages: No page available

10.1111/nmo.13403 | PMID 30062771 Get It

AbstractBackgroundThe mechanism by which obesity leads to damage independent of reflux is unclear. We aimed to determine the influence of obesity on mean nocturnal baseline impedance (MNBI), a functional measure of the epithelial barrier, in the presence and absence of acid reflux, using ambulatory pH impedance measurements.MethodsTwenty‐four‐hour pH impedance studies performed off medications in Caucasian men with a normal endoscopic examination were assessed for level of acid exposure and MNBI. Four patient groups were studied: Group 1, Not obese and normal acid exposure; Group 2, Obese and normal acid exposure; Group 3, Not obese and increased acid exposure; and Group 4, Obese with increased acid exposure.ResultsOne hundred patients were studied (25 in each group). Mean esophageal mucosal impedance (MI) was substantially lower in obese patients without reflux (Group 2) and non‐obese patients with reflux (Group 3) compared to normal controls (non‐obese, no reflux, Group 1). MI was progressively lower in the distal (vs the proximal) esophagus in GER patients, compared to those without GER. This difference persisted in the presence or absence of obesity. In contrast, in obese patients, the mean MI was significantly lower throughout the esophagus when compared to the non‐obese patients and also persisted in the presence and absence of accompanying reflux. Obesity and reflux were both independently negatively correlated with MI.ConclusionObesity is associated with abnormal esophageal MNBI. In contrast to gastro‐esophageal reflux, this decrease is pan‐esophageal. These data may support a systemic mechanism by which obesity alters the esophageal barrier function.
Minimally Invasive Resection of Deep-seated High-grade Gliomas Using Tubular Retractors and Exoscopic Visualization
Iyer, Rajiv R. , Chaichana, Kaisorn L.

Journal of Neurological Surgery Part A: Central European Neurosurgery | July 13, 2018 | Volume: 79 | Issue: 04 | Pages: 330-336

10.1055/s-0038-1641738 | PMID 29684925 Get It

Background and Study Aims/Objective Deep-seated high-grade gliomas (HGGs) represent a unique surgical challenge because they reside deep to critical cortical and subcortical structures and infiltrate functional areas of the brain. Therefore, accessing and resecting these tumors can often be challenging and associated with significant morbidity. We describe the use of minimally invasive approaches to access deep-seated HGGs to achieve extensive resections while minimizing surgical morbidity. Materials and Methods All patients who underwent resection of a deep-seated intraparenchymal HGG with the use of a tubular retractor with exoscopic visualization from January 2016 to May 2017 were identified prospectively at a single institution. Variables evaluated included tumor location, pre- and postoperative neurologic function, extent of resection, and length of hospital stay. Results Overall, 14 patients underwent resection of an HGG (11 glioblastomas, 3 anaplastic astrocytomas) with a tubular retractor under exoscopic visualization. Seven tumors (50%) involved the thalamus, three (21%) the motor corticospinal tract, two (14%) the inferior frontal occipital fasciculus, one (7%) each the basal ganglia and optic pathway. The median preoperative Karnofsky Performance Score (KPS) was 70 (interquartile range: 55–80), where the major presenting symptom was motor weakness in seven (50%). The average plus or minus the standard error of the mean percentage resection was 97.0 ± 1.2%. The median hospital stay was 4 days (range: 2–7). At 1 month postoperatively, median postoperative KPS (within 30 days) was 87 (range: 77–90), where eight (57%) were improved, five (36%) were stable, and one (7%) was worse postoperatively. Conclusions Deep-seated HGGs can be accessed, visualized, and resected using tubular retractors and exoscopic visualization with minimal morbidity.
History of the World Society for Pediatric and Congenital Heart Surgery: The First Decade
Tchervenkov, Christo I., Kurosawa, Hiromi, Mavroudis, Constantine , Jatene, Marcelo Biscegli , Al‐Halees, Zohair , Çïçek, Sertaç , Sandoval, Néstor , Backer, Carl L., Cervantes, Jorge , Edwin, Frank , Finucane, Kirsten , Iyer, Krishna, Kinsley, Robin H. , Kreutzer, Christián , Liu, Jinfen , Maruszewski, Bohdan , Sarris, George E. , Jonas, Richard A. , Çiçek, Sertaç M, Jacobs, Jeffrey P. , Stellin, Giovanni , Dearani, Joseph A. , Ebels, Tjark , Fragata, José , Kirklin, James K. , Louis, James D. St.

World Journal for Pediatric and Congenital Heart Surgery | June 26, 2018 | Volume: 9 | Issue: 4 | Pages: 392-406

10.1177/2150135118775962 | PMID 29945512 Get It

The World Society for Pediatric and Congenital Heart Surgery (WSPCHS) is the largest professional organization in the world dedicated to pediatric and congenital heart surgery. The purpose of this article is to document the first decade of the history of WSPCHS from its formation in 2006, to summarize the current status of WSPCHS, and to consider the future of WSPCHS. The WSPCHS was incorporated in Canada on April 7, 2011, with a head office in Montreal, Canada. The vision of the WSPCHS is that every child born anywhere in the world with a congenital heart defect should have access to appropriate medical and surgical care. The mission of the WSPCHS is to promote the highest quality comprehensive cardiac care to all patients with congenital heart disease, from the fetus to the adult, regardless of the patient’s economic means, with an emphasis on excellence in teaching, research, and community service.
Easing the Tension Between Palliative Care and Intensive Care in Chronic Obstructive Pulmonary Disease
Iyer, Anand , Benzo, Roberto P. , Bakitas, Marie , Iyer, Anand S

Journal of Palliative Care | June 15, 2018 | Volume: 33 | Issue: 3 | Pages: 123-124

10.1177/0825859718782505 | PMID 29902961 Get It

Integrating artificial intelligence with real-time intracranial EEG monitoring to automate interictal identification of seizure onset zones in focal epilepsy
Varatharajah, Yogatheesan , Berry, Brent , Cimbálník, Jan , Křemen, Václav , Stead, Matt, Brinkmann, Benjamin H. , Van Gompel, Jamie, Brinkmann, Benjamin, Brinkmann, Benjamin H , Kremen, Vaclav , Gompel, Jamie J. Van , Iyer, Ravishankar K. , Worrell, Gregory A.

Journal of Neural Engineering | June 1, 2018 | Volume: 15 | Issue: 4 | Pages: 046035

10.1088/1741-2552/aac960 | PMID 29855436 Get It

Abstract Objective . An ability to map seizure-generating brain tissue, i.e. the seizure onset zone (SOZ), without recording actual seizures could reduce the duration of invasive EEG monitoring for patients with drug-resistant epilepsy. A widely-adopted practice in the literature is to compare the incidence (events/time) of putative pathological electrophysiological biomarkers associated with epileptic brain tissue with the SOZ determined from spontaneous seizures recorded with intracranial EEG, primarily using a single biomarker. Clinical translation of the previous efforts suffers from their inability to generalize across multiple patients because of (a) the inter-patient variability and (b) the temporal variability in the epileptogenic activity. Approach . Here, we report an artificial intelligence-based approach for combining multiple interictal electrophysiological biomarkers and their temporal characteristics as a way of accounting for the above barriers and show that it can reliably identify seizure onset zones in a study cohort of 82 patients who underwent evaluation for drug-resistant epilepsy. Main results . Our investigation provides evidence that utilizing the complementary information provided by multiple electrophysiological biomarkers and their temporal characteristics can significantly improve the localization potential compared to previously published single-biomarker incidence-based approaches, resulting in an average area under ROC curve (AUC) value of 0.73 in a cohort of 82 patients. Our results also suggest that recording durations between 90 min and 2 h are sufficient to localize SOZs with accuracies that may prove clinically relevant. Significance . The successful validation of our approach on a large cohort of 82 patients warrants future investigation on the feasibility of utilizing intra-operative EEG monitoring and artificial intelligence to localize epileptogenic brain tissue. Broadly, our study demonstrates the use of artificial intelligence coupled with careful feature engineering in augmenting clinical decision making.
Clinical Outcomes of Weight-Based Norepinephrine Dosing in Underweight and Morbidly Obese Patients: A Propensity-Matched Analysis
Kotecha, Aditya , Vallabhajosyula, Saraschandra , Apala, Dinesh , Frazee, Erin, Kotecha, Aditya A, Apala, Dinesh R , Vallabhajosyula, Saraschandra , Frazee, Erin, Iyer, Vivek

Journal of Intensive Care Medicine | April 9, 2018 | Volume: 35 | Issue: 6 | Pages: 554-561

10.1177/0885066618768180 | PMID 29628015 Get It

Background: Weight-based dosing strategy for norepinephrine in septic shock patients with extremes of body mass index has been lesser studied. Methods: This historical study of adult septic shock patients was conducted from January 1, 2010, to December 31, 2015, at all intensive care units (ICUs) in Mayo Clinic, Rochester. Patients with documented body mass index were classified into underweight (body mass index <18.5 kg/m 2 ), normal weight (18.5-24.9 kg/m 2 ), and morbidly obese (≥40 kg/m 2 ) patients. Patients with repeat ICU admissions, ICU stay <1 day, and body mass index 25 to 39.9 kg/m 2 were excluded. The primary outcome was in-hospital mortality, and secondary outcomes included cumulative norepinephrine exposure acute kidney injury, cardiac arrhythmias, and 1-year mortality. Two-tailed P < .05 was considered statistically significant. Results: From 2010 to 2015, 2016 patients met inclusion—145, 1406, and 466 patients, respectively, in underweight, normal weight, and morbidly obese cohorts. Underweight patients used the highest peak dose and absolute exposure was greatest for morbidly obese patients. In-hospital mortality decreased with increasing log 10 body mass index: 41.4% (underweight), 28.4% (normal weight), and 24.7% (morbidly obese), respectively ( P < .001); however, this relationship was not noted at 1 year. Unadjusted log 10 norepinephrine cumulative exposure (mg) was associated with higher in-hospital mortality, acute kidney injury, cardiac arrhythmias, and 1-year mortality. After adjustment for demographics, body mass index, comorbidity, and illness severity, log 10 norepinephrine exposure was an independent predictor of in-hospital mortality (odds ratio 2.4 [95% confidence interval, 2.0-2.8]; P < .001) and 1-year mortality (odds ratio 1.7 [95% confidence interval, 1.5-2.0]; P < .001). In a propensity-matched analysis of 1140 patients, log 10 norepinephrine was an independent predictor of in-hospital mortality (odds ratio 2.2 [95% confidence interval, 1.8-2.6]; P < .001). Conclusions: Morbidly obese patients had lower in-hospital mortality but had higher 1-year mortality compared to normal weight and underweight patients. Cumulative norepinephrine exposure was highest in morbidly obese patients. Total norepinephrine exposure was an independent mortality predictor in septic shock.
Barrett Esophagus Length, Nodularity, and Low-grade Dysplasia are Predictive of Progression to Esophageal Adenocarcinoma
Solanky, Dipesh , Krishnamoorthi, Rajesh , Crews, Nicholas R. , Johnson, Michele L., Wolfsen, Herbert C. , Fleischer, David E., Ramirez, Francisco C. , Katzka, David A. , Buttar, Navtej , Iyer, Prasad G. , Crews, Nicholas, Johnson, Michele, Wolfsen, Herbert, Fleischer, David, Katzka, David, Wang, Kenneth

Journal of Clinical Gastroenterology | April 2, 2018 | Volume: 53 | Issue: 5 | Pages: 361-365

10.1097/mcg.0000000000001027 | PMID 29608452 Get It

Goals: To investigate factors predictive of progression from nondysplastic Barrett esophagus (NDBE) or low-grade dysplasia (LGD) to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) using a large, prospective cohort of patients, wherein all esophageal biopsies undergo expert gastrointestinal pathologist review. Background: Efficacy and cost-effectiveness of endoscopic surveillance to detect incident EAC in the setting of Barrett esophagus (BE), particularly in NDBE patients, is questioned. Previous studies have reported factors predictive of progression to EAC to guide surveillance intervals, but their strength is limited by small sample size and absence of expert gastrointestinal pathologist involvement in esophageal biopsy review. Study: NDBE and LGD subjects were identified from a prospective registry in a tertiary care center. “Progressors” were BE subjects who developed HGD/EAC>12 months after the initial NDBE or LGD diagnosis. Cox proportional hazards model were used to identify predictors of progression. Results: In total, 318 with NDBE and 301 with BE-LGD (mean age, 62.6 y, 85% male) were included. The mean follow-up was 5.3 years. The 7 NDBE and 21 LGD subjects progressed to HGD/EAC. BE length [hazards ratio (HR), 1.16; 95% confidence interval (CI), 1.03-1.29], presence of nodularity (HR, 4.98; 95% CI, 1.80-11.7), and baseline LGD (HR, 2.57; 95% CI, 1.13-6.57) were significant predictors of progression on multivariate analysis. Conclusions: In this well-defined cohort of NDBE and BE-LGD subjects, BE length, presence of LGD, and nodularity were independent predictors of progression to HGD/EAC. These factors may aid in identifying high-risk patients who may benefit from closer endoscopic surveillance/therapy.
Association of sporadic and familial Barrett's esophagus with breast cancer
Chan, Megan , Blum, Andrew E., Chandar, Apoorva K., Emmons, Agnieszka, Shindo, Yuri, Brock, Wendy , Wang, J S, Iyer, Prasad G. , Shaheen, Nicholas J. , Thota, Prashanthi N. , Guda, Kishore , Chak, Amitabh , Falk, Gary W. , Canto, Marcia Irene , Grady, William M. , Abrams, Julian A

Diseases of the Esophagus | March 8, 2018 | Volume: 31 | Issue: 4 | Pages: No page available

10.1093/dote/doy007 | PMID 29528378 Get It

Impact of Age on Outcomes in Hospitalized Patients with Hereditary Hemorrhagic Telangiectasia
Iyer, Vivek , Brinjikji, Waleed , Apala, Dinesh , Pannu, Bibek , Kotecha, Aditya , Leise, Michael D. , Kamath, Patrick S. , Misra, Sanjay , Krowka, Michael J. , Wood, Christopher P. , Swanson, Karen L., Iyer, Vivek N , Pannu, Bibek S, Misra, Sanjay , Lanzino, Giuseppe

Advances in Hematology | February 11, 2018 | Volume: 2018 | Issue: No issue available | Pages: 1-8

10.1155/2018/4798425 | PMID 29610574 Get It

Background. There is little published literature regarding the impact of age on outcomes amongst hospitalized HHT (hereditary hemorrhagic telangiectasia) patients. Methods. The Nationwide Inpatient Sample (NIS) was used to obtain data on all hospital discharges occurring in HHT patients from 2000 to 2012. The association between admission age and HHT-related complications and outcomes were studied. Results. 10293 hospitalizations in HHT patients from 2000 to 2012 were included. Patients > 50 accounted for 77% of all admissions with 30% of admissions occurring in the 51–65 age group. Bleeding related complications were the most frequent (62.7%, n=6455 hospitalizations), followed by cardiovascular (41%, n=4216), neurological (12.4%, n=1276), and hepatobiliary (6.4%, n=660) complications. Patients older than 50 accounted for 83% of bleeding events, 90% of cardiovascular events, 58% of neurologic events, and 81% of hepatobiliary events. The vast majority (83%) of medical and surgical procedures were performed in those older than 50 years of age. Older patients also experienced higher rates of death. Conclusion. Aging has significant adverse impacts on rates of hospitalization, complications, and outcomes amongst HHT patients in the United States. Except for neurologic complications, the vast majority of this disease burden is borne by patients older than 50 years.
Comparative Assessment of Patient Preferences and Tolerability in Barrett Esophagus Screening
Blevins, Christopher H. , Egginton, Jason S. , Shah, Nilay D., Johnson, Michele L., Iyer, Prasad G.

Journal of Clinical Gastroenterology | January 23, 2018 | Volume: 52 | Issue: 10 | Pages: 880-884

10.1097/mcg.0000000000000991 | PMID 29369237 Get It

Goals: To determine patient preference for the Barrett esophagus (BE) screening techniques. Background: Sedated esophagogastroduodenoscopy (sEGD) and unsedated transnasal endoscopy (uTNE) are both potential techniques for BE screening. However, systematic assessment of patient preference for these 2 techniques is lacking. As part of a comparative effectiveness randomized trial of BE screening modalities, we measured short-term patient preferences for the following approaches: in-clinic uTNE (huTNE), mobile-based uTNE (muTNE), and sEGD using a novel assessment instrument. Study: Consenting community patients without known BE were randomly assigned to receive huTNE, muTNE, or sEGD, followed by a telephone administered preference and tolerability assessment instrument 24 hours after study procedures. Patient preference was measured by the waiting trade-off method. Results: In total, 201 patients completed screening with huTNE (n=71), muTNE (n=71), or sEGD (n=59), and a telephone interview. Patients’ preferences for sEGD and uTNE using the waiting trade-off method were comparable (P=0.51). Although tolerability scores were superior for sEGD (P<0.001) compared with uTNE, scores for uTNE examinations were acceptable. Conclusions: Patient preference is comparable between sEGD and uTNE for diagnostic examinations conducted in an endoscopy suite or in a mobile setting. Given acceptable tolerability, uTNE may be a viable alternative to sEGD for BE screening.