221 research outputs found
‘Standard’ cosmological model and beyond with CMB
No full text'Standard' cosmological model and beyond with CMB
Tarun Souradeep
Published 20 May 2011 • 2011 IOP Publishing Ltd
Classical and Quantum Gravity, Volume 28, Number 11
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Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007, India
Dates
Received 11 January 2011
Published 20 May 2011
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Tarun Souradeep 2011 Class. Quantum Grav. 28 114016
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DOI
https://doi.org/10.1088/0264-9381/28/11/114016
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Abstract
Observational cosmology has made very rapid progress in the past decade. The ability to quantify the universe has largely improved due to observational constraints coming from structure formation measurements; cosmic microwave background (CMB) anisotropy and, more recently, polarization have played a very important role. Besides precise determination of various parameters of the 'standard' cosmological model, observations have also established some important basic tenets that underlie models of cosmology and structure formation in the universe—'acausally' correlated initial perturbations in a flat, statistically isotropic universe, adiabatic nature of primordial density perturbations. These are consistent with the expectation of the paradigm of inflation and the generic prediction of the simplest realization of an inflationary scenario in the early universe. Furthermore, gravitational instability is the established mechanism for structure formation from these initial perturbations. The signature of primordial perturbations observed as the CMB anisotropy and polarization is the most compelling evidence for new, possibly fundamental, physics in the early universe. The community is now looking beyond the estimation of parameters of a working 'standard' model of cosmology for subtle, characteristic signatures from early universe physics
Neonatal pain management
No full textThe past 2-3 decades have seen dramatic changes in the approach to pain management in the neonate. These practices started with refuting previously held misconceptions regarding nociception in preterm infants. Although neonates were initially thought to have limited response to painful stimuli, it was demonstrated that the developmental immaturity of the central nervous system makes the neonate more likely to feel pain. It was further demonstrated that untreated pain can have long-lasting physiologic and neurodevelopmental consequences. These concerns have resulted in a significant emphasis on improving and optimizing the techniques of analgesia for neonates and infants. The following article will review techniques for pain assessment, prevention, and treatment in this population with a specific focus on acute pain related to medical and surgical conditions
Regional anesthesia for an upper extremity amputation for palliative care in a patient with end-stage osteosarcoma complicated by a large anterior mediastinal mass
No full textMumin Hakim,1 Candice Burrier,1 Tarun Bhalla,1 Vidya T Raman,1 David P Martin,1,2 Olamide Dairo,1 Joel L Mayerson,3,4 Joseph D Tobias1,2 1Department of Anesthesiology and Pain Medicine, Nationwide Children's Hospital, 2Department of Anesthesiology and Pain Medicine, The Ohio State University, 3Department of Orthopedic Surgery, Nationwide Children's Hospital, 4Department of Orthopedic Surgery, The Ohio State University, Columbus, OH, USA Abstract: Tumor progression during end-of-life care can lead to significant pain, which at times may be refractory to routine analgesic techniques. Although regional anesthesia is commonly used for postoperative pain care, there is limited experience with its use during home hospice care. We present a 24-year-old male with end-stage metastatic osteosarcoma who required anesthetic care for a right-sided above-the-elbow amputation. The anesthetic management was complicated by the presence of a large mediastinal mass, limited pulmonary reserve, and severe chronic pain with a high preoperative opioid requirement. Intraoperative anesthesia and postoperative pain management were provided by regional anesthesia using an interscalene catheter. He was discharged home with the interscalene catheter in place with a continuous local anesthetic infusion that allowed weaning of his chronic opioid medications and the provision of effective pain control. The perioperative applications of regional anesthesia in palliative and home hospice care are discussed. Keywords: osteosarcoma, peripheral nerve block, palliative car
RNA editing of the human Kv1.1 potassium channel
No full textPotassium (K+) channels in the nervous system serve many roles: maintaining the resting membrane potential, regulating cell volume, and tuning the firing properties of a given neuron. The delayed rectifier function of K+ channels allows nerve cells to efficiently repolarize following an action potential. Mutations in K+ channels have been reported to cause many neurological diseases. Episodic Ataxia/Myokymia Syndrome Type 1 (EA1) is the only human ataxia known to be caused by dysfunction of a K+ channel EA1 is an inherited autosomal dominant human neurological disorder that affects both peripheral and central nerve functions. In addition, patients affected by EA1 have an estimated 10-fold increased risk to develop epilepsy. The gene responsible for EA1 has been identified as KCNA1, which encodes the Shaker-like voltage gated potassium channel Kv1.1 in mammals. Most mutations that underlie EA1 have been shown to alter the biophysical properties of Kv1.1 channels. ^ Adenosine-to-inosine (A-to-I) pre-mRNA editing is a post-transcriptional chemical modification, which generates an RNA transcript with a nucleotide sequence different from its gene. We have discovered that the KCNA1 transcript is a target of RNA editing in its coding sequence at a very highly conserved amino-acid position. We have also observed that the spatial regulation of RNA editing for Kv1.1 is evolutionarily conserved between rodents and humans. RNA editing at this site causes an isoleucine to valine change at a residue position known to be important for channel function. The studies below aim to understand the functional consequences of RNA editing of Kv1.1 in the mammalian nervous system.
Spinal anesthesia instead of general anesthesia for infants undergoing tendon Achilles lengthening
No full textMohammad AlSuhebani,1 David P Martin,1,2 Lance M Relland,1,2 Tarun Bhalla,1,2 Allan C Beebe,3 Amanda T Whitaker,3 Walter Samora,3 Joseph D Tobias1,2 1Department of Anesthesiology & Pain Medicine, Nationwide Children’s Hospital, Columbus, OH, USA; 2Department of Anesthesiology & Pain Medicine, The Ohio State University College of Medicine, Columbus, OH, USA; 3Department of Orthopedic Surgery, Nationwide Children’s Hospital and The Ohio State University College of Medicine, Columbus, OH, USA Abstract: Spinal anesthesia (SA) has been used relatively sparingly in the pediatric population, as it is typically reserved for patients in whom the perceived risk of general anesthesia is high due to comorbid conditions. Recently, concern has been expressed regarding the potential long-term neurocognitive effects of general anesthesia during the early stages of life. In view of this, our center has developed a program in which SA may be used as the sole agent for applicable surgical procedures. While this approach in children is commonly used for urologic or abdominal surgical procedures, there have been a limited number of reports of its use for orthopedic procedures in this population. We present the use of SA for 6 infants undergoing tendon Achilles lengthening, review the use of SA in orthopedic surgery, describe our protocols and dosing regimens, and discuss the potential adverse effects related to this technique. Keywords: spinal anesthesia, orthopedic surgery, tendon Achilles lengthenin
Leviathans: Headspace-like behemoths swallow resources
No full texthttps://orcid.org/0000-0003-3351-6911 Looi Jeffrey CL 1 https://orcid.org/0000-0002-9264-5310 Allison Stephen 2 Bastiampillai Tarun 2 3 1 Academic Unit of Psychiatry & Addiction Medicine, ANU Medical School, Canberra Hospital, Canberra, ACT, Australia 2 Discipline of Psychiatry, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia 3 South Australian Health and Medical Research Institute, Adelaide, SA, Australia Jeffrey CL Looi, Academic Unit of Psychiatry & Addiction Medicine, ANU Medical School, Canberra Hospital, Canberra, ACT 2605, Australia. Email: [email protected] 11 2019 53 11 1050 1051 © The Royal Australian and New Zealand College of Psychiatrists 2019 2019 The Royal Australian and New Zealand College of Psychiatrists Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article. Funding The author(s) received no financial support for the research, authorship and/or publication of this article. ORCID iDs Jeffrey CL Looi https://orcid.org/0000-0003-3351-6911 Stephen Allison https://orcid.org/0000-0002-9264-5310Peer-reviewe
Optimizing the securement of epidural catheters: an in vitro trial
No full textMohammed Hakim,1 Alexander B Froyshteter,2 Hina Walia,1 Dmitry Tumin,1,3 Giorgio Veneziano,1 Tarun Bhalla,1,4 Joseph D Tobias1,3,4 1Department of Anesthesiology and Pain Medicine, Nationwide Children’s Hospital, Columbus, OH, USA; 2Department of Anesthesiology, Rush University Medical Center, Chicago, IL, USA; 3Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA; 4Department of Anesthesiology and Pain Medicine, The Ohio State University College of Medicine, Columbus, OH, USA Introduction: Epidural anesthesia is frequently used to provide postoperative analgesia following major surgical procedures. Secure fixation of the epidural catheter is necessary to prevent premature dislodgment and loss of epidural analgesia. Using an in vitro model, the current prospective study evaluates different types of dressings for securement of an epidural catheter by quantifying the force in Newtons (N) required for dislodgment using a digital force gage. Methods: Four methods of epidural catheter securement were used on a simulator mannequin: 1) Suresite® Window Clear Dressing, 2) Op-Site Post-Op® Visible Dressing, 3) Steri-Strips® and Suresite Window Clear Dressing, and 4) Steri-Strips and Op-Site Post-Op Visible Dressing. Each method of securement was assessed 10 times to calculate the mean force required to dislodge the catheter. Mean force of dislodgment for each method was compared using parametric tests. Results: The force (mean ± SD) required for catheter dislodgment for the four methods was 14.0±2.9, 2, 10.7±1.5, 8.6±2.3, and 9.6±2.2 N, respectively. The pairwise difference showed that the Suresite Window Clear Dressing was the best securement method when compared with other methods. Conclusion: Our study demonstrates the advantage of the Suresite Window Clear Dressing in securing the epidural catheter. Future clinical trials are needed to validate these findings. Keywords: epidural catheter, securement, dressing
Patient-controlled analgesia in the pediatric population: morphine versus hydromorphone
No full textMatthew DiGiusto,2 Tarun Bhalla,1 David Martin,1 Derek Foerschler,3 Megan J Jones,2 Joseph D Tobias1 1Department of Anesthesiology and Pain Medicine, Nationwide Children's Hospital and the Ohio State University, 2The Ohio State School of Medicine, 3Department of Anesthesiology, The Ohio State University, Columbus, OH, USA Objective: Patient controlled analgesia (PCA) is commonly used to provide analgesia following surgical procedures in the pediatric population. Morphine and hydromorphone remain the most commonly used opioids for PCA. Although both are effective, adverse effects may occur. When these adverse effects are unremitting or severe, opioid rotation may be required. In this study, we retrospectively evaluated PCA use, the adverse effect profile, and the frequency of opioid rotation. Methods: This retrospective study was performed at Nationwide Children’s Hospital (Columbus, OH). The hospital's electronic registry was queried for PCA use delivering either morphine or hydromorphone from January 1, 2008 to December 31, 2010. Results: A total of 514 patients were identified, that met study entry criteria. Of the 514 cases, 298 (56.2%) were initially started on morphine and 225 (43.8%) were initially started on hydromorphone. There were a total of 26 (5.1%) opioid changes in the cohort of 514 patients. Of the 26 switches, 23 of 298 (7.7%) were from morphine to hydromorphone, and 3 of 225 (1.3%) were from hydromorphone to morphine (P=0.0008). Of the 17 morphine-to-hydromorphone switches with adverse effects, pruritus (64.7%), and inadequate pain control (47.1%) were the most common side effects. The most common side effect resulting in a hydromorphone-to-morphine switch was nausea (66.7%). Conclusion: PCA switches from morphine-to-hydromorphone (88.5%) were more common than vice-versa (11.5%). The most common reasons for morphine-to-hydromorphone switch were pruritus and inadequate pain control. These data suggest that a prospective study is necessary to determine the side effect differences between morphine and hydromorphone in pediatric PCA. Keywords: acute pain, analgesia, opioids, pediatri
Safety and efficacy of nurse-controlled analgesia in patients less than 1 year of age
No full textHina Walia,1 Dmitry Tumin,1 Sharon Wrona,1 David Martin,1,2 Tarun Bhalla,1,2 Joseph D Tobias,1-3 1Department of Anesthesiology and Pain Medicine, Nationwide Children’s Hospital, 2Department of Anesthesiology and Pain Medicine, 3Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA Background: The management of acute pain presents unique challenges in the younger pediatric population. Although patient-controlled devices are frequently used in patients ≥6 years of age, alternative modes of analgesic delivery are needed in infants.Objective: To examine the safety and efficacy of nurse-controlled analgesia (NCA) in neonates less than 1 year of age.Methods: Data from patients <1 year of age receiving NCA as ordered by the Acute Pain Service at our institution were collected over a 5-year period and reviewed retrospectively. The primary outcomes were activation of the institution’s Rapid Response Team (RRT) or Code Blue, signifying severe adverse events. Pain score after NCA initiation was a secondary outcome.Results: Among 338 girls and 431 boys, the most common opioid used for NCA was fentanyl, followed by morphine and hydromorphone. There were 39 (5%) cases involving RRT or Code Blue activation, of which only one (Code Blue) was activated due to a complication of NCA (apnea). Multivariable logistic regression demonstrated morphine NCA to be associated with greater odds of RRT activation (OR=3.29, 95% CI=1.35, 8.03, P=0.009) compared to fentanyl NCA. There were no statistically significant differences in pain scores after NCA initiation across NCA agents.Conclusion: NCA is safe in neonates and infants, with comparable efficacy demonstrated for the three agents used. The elevated incidence of RRT activation in patients receiving morphine suggests caution in its use and consideration of alternative agents in this population. Keywords: nurse-controlled analgesia, pain medicine, Rapid Response Tea
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