• Altered pharmacological effects of adrenergic agonists during hypothermia 

      Dietrichs, Erik Sveberg; Sager, Georg; Tveita, Torkjel (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-05)
      Rewarming from accidental hypothermia is often complicated by hypothermia-induced cardiac dysfunction, calling for immediate pharmacologic intervention. Studies show that although cardiac pharmacologic support is applied when rewarming these patients, a lack of updated treatment recommendations exist. Mainly due to lack of clinical and experimental data, neither of the international guidelines ...
    • Cardiovascular Effects of Epinephrine During Experimental Hypothermia (32°C) With Spontaneous Circulation in an Intact Porcine Model 

      Mohyuddin, Rizwan; Dietrichs, Erik Sveberg; Sundaram, Predip; Kondratiev, Timofei V.; Figenschou, Marie Fjellanger; Sieck, Gary C.; Tveita, Torkjel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-06)
      <i>Aims</i>: Rewarming from accidental hypothermia and therapeutic temperature management could be complicated by cardiac dysfunction. Although pharmacologic support is often applied when rewarming these patients, updated treatment recommendations are lacking. There is an underlying deficiency of clinical and experimental data to support such interventions and this prevents the development of clinical ...
    • Comparison between two pharmacologic strategies to alleviate rewarming shock: vasodilation vs. inodilation 

      Håheim, Brage; Kondratyev, Timofey; Dietrichs, Erik Sveberg; Tveita, Torkjel (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-12)
      Rewarming from hypothermia is often challenged by coexisting cardiac dysfunction, depressed organ blood flow (OBF), and increased systemic vascular resistance. Previous research shows cardiovascular inotropic support and vasodilation during rewarming to elevate cardiac output (CO). The present study aims to compare the effects of inodilatation by levosimendan (LS) and vasodilation by nitroprusside ...
    • Dopamine agonist serum concentrations and impulse control disorders in Parkinson's disease 

      Staubo, Sara C.; Fuskevåg, Ole Martin; Toft, Mathias; Lie, Ingeborg H.; Alvik, Kirsti Margrete Johansen; Jostad, Pål; Tingvoll, Stein H.; Lilleng, Hallvard; Rosqvist, Kristina; Størset, Elisabet; Odin, Per; Dietrichs, Espen; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-13)
      Background and purpose: Impulse control disorders (ICDs) are common among Parkinson's disease patients using dopamine agonists. We wanted to determine whether ICD patients have higher dopamine agonist serum concentrations than those without any sign of ICD.<p> <p>Methods: Patients who used either pramipexole or ropinirole depot once daily were screened for ICDs using the validated Questionnaire ...
    • E.S. Dietrichs og medarbeidere svarer 

      Dietrichs, Erik Sveberg; Solhaug, Vigdis; Haslemo, Tore; Kringen, Marianne K.; Molden, Espen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-11-21)
    • Genotyping av pasienter behandlet med selektive serotoninreopptakshemmere 

      Solhaug, Vigdis; Haslemo, Tore; Kringen, Marianne Kristiansen; Molden, Espen; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-26)
      BAKGRUNN - Selektive serotoninreopptakshemmere (SSRI) brukes av over 180 000 mennesker i Norge. Enzymene CYP2D6 og CYP2C19 er sentrale i metabolismen av SSRI-antidepressiver. Serotonintransportøren kodet av SLC6A4 kan ha betydning for effekten av medikamentene.<p> <p>MATERIALE OG METODE - Alle pasienter som hadde blitt genotypet for CYP2D6, CYP2C19 og SLC6A4 ved Senter for psykofarmakologi i ...
    • How should tranexamic acid be administered in haemorrhagic shock? - continuous serum concentration measurements in a swine model 

      Lynghaug, Trine; Bakke, Håkon Kvåle; Fuskevåg, Ole Martin; Nielsen, Erik Waage; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11)
      Background: Tranexamic acid (TXA) reduces mortality in trauma patients. Intramuscular (IM) administration could be advantageous in low-resource and military settings. Achieving the same serum concentration as intravenous (IV) administration is important to achieve equal mortality reduction. Therefore, we aimed to investigate whether dividing an IM dose of TXA between two injection sites and whether ...
    • Hypothermia and cardiac electrophysiology: a systematic review of clinical and experimental data 

      Dietrichs, Erik Sveberg; Tveita, Torkjel; Smith, Godfrey L (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-12-13)
      Moderate therapeutic hypothermia procedures are used in post-cardiac arrest care, while in surgical procedures, lower core temperatures are often utilized to provide cerebral protection. Involuntary reduction of core body temperature takes place in accidental hypothermia and ventricular arrhythmias are recognized as a principal cause for a high mortality rate in these patients. We assessed both ...
    • Identification and experimental confirmation of novel cGMP efflux inhibitors by virtual ligand screening of vardenafil-analogues 

      Kashgari, Farzane Kuresh; Ravna, Aina Westrheim; Sager, Georg; Lyså, Roy Andre; Enyedy, Istvan; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-28)
      <i>Background</i> - Clinical studies have reported overexpression of PDE5 and elevation of intracellular cyclic GMP in various types of cancer cells. ABCC5 transports cGMP out of the cells with high affinity. PDE5 inhibitors prevent both cellular metabolism and cGMP efflux by inhibiting ABCC5 as well as PDE5. Increasing intracellular cGMP is hypothesized to promote apoptosis and growth restriction ...
    • Inhibition of ABCC5-mediated cGMP transport by progesterone, testosterone and their analogues 

      Odland, Sondre Ulstein; Ravna, Aina Westrheim; Smaglyukova, Natalia; Dietrichs, Erik Sveberg; Sager, Georg (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-13)
      The biodynamics and biokinetics of sex hormones are complex. In addition to the classical steroid receptors (nuclear receptors), these hormones act through several non-genomic mechanisms. Modulation of ABC-transporters by progesterone represents a non-genomic mechanism. In the present study, we employed inside out vesicles from human erythrocytes to characterize high affinity cGMP transport by ABCC5 ...
    • Intramuscular uptake of tranexamic acid during haemorrhagic shock in a swine model 

      Bakke, Håkon Kvåle; Fuskevåg, Ole Martin; Nielsen, Erik Waage; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-18)
      Background: Tranexamic acid (TXA) reduce mortality in bleeding trauma patients, with greater efect if administered early. Serum concentrations above 10 µg/mL are considered sufcient to inhibit fbrinolysis. Normally administered intravenously (i.v.), TXA can also be administered intramuscularly (i.m.). This could be advantageous in low resource and military settings, if sufcient serum concentrations ...
    • Is hypothermia more neuroprotective than avoiding fever after cardiac arrest? 

      Dietrichs, Erik Sveberg; Myles, Rachel; Smith, Godfrey L (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-27)
      Hypothermia was increasingly proposed as a neuroprotective therapy in the 1990s, culminating in the publication of two randomized trials in 2002, which showed beneficial effects of therapeutic hypothermia in comatose survivors of cardiac arrest.1,2 Therapeutic hypothermia was subsequently included in guidelines for the treatment of this patient group. However, doubt as to whether hypothermia provided ...
    • Moderate but not severe hypothermia causes pro-arrhythmic changes in cardiac electrophysiology 

      Dietrichs, Erik Sveberg; McGlynn, Karen; Allan, Andrew; Connolly, Adam; Bishop, Martin; Burton, Francis; Kettlewell, Sarah; Myles, Rachel; Tveita, Torkjel; Smith, Godfrey L (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-07)
      <i>Aims</i> - Treatment of arrhythmias evoked by hypothermia/rewarming remains challenging, and the underlying mechanisms are unclear. This <i>in vitro</i> experimental study assessed cardiac electrophysiology in isolated rabbit hearts at temperatures occurring in therapeutic and accidental hypothermia.<p><p> <i>Methods and results</i> - Detailed ECG, surface electrogram, and panoramic optical ...
    • Moderate but not severe hypothermia increases intracellular cyclic AMP through preserved production and reduced elimination 

      Kuzmiszyn, Adrina Kalasho; Selli, Anders Lund; Furuholmen, Markus; Smaglyukova, Natalia; Kondratiev, Timofei; Fuskevåg, Ole Martin; Sager, Georg; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-14)
      Rewarming from accidental hypothermia could be complicated by acute cardiac dysfunction but providing supportive pharmacotherapy at low core temperatures is challenging. Several pharmacological strategies aim to improve cardiovascular function by increasing cAMP in cardiomyocytes as well as cAMP and cGMP levels in vascular smooth muscle, but it is not clear what effects temperature has on cellular ...
    • Molecular modeling study of the testosterone metabolizing enzyme UDP-glucuronosyltransferase 2B17 

      Trane, Ingmar; Sager, Georg; Dietrichs, Erik Sveberg; Ravna, Aina Westrheim (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-20)
      The dominant sex hormone testosterone is mainly metabolized by liver enzymes belonging to the uridine-diphospho (UDP) glucuronosyltransferase (UGT) family. These enzymes are the main phase II enzymes, and they have an important role in the detoxification of endogenous and exogenous compounds in humans. The aim of the present study was to improve the understanding of the binding properties of UGT2B17. ...
    • A novel ECG-biomarker for cardiac arrest during hypothermia 

      Dietrichs, Erik Sveberg; Tveita, Torkjel; Myles, Rachel; Smith, Godfrey L (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-10)
      <i>Background</i> - Treatment of arrhythmias evoked by accidental or therapeutic hypothermia and rewarming remains challenging. We aim to find an ECG-biomarker that can predict ventricular arrhythmias at temperatures occurring in therapeutic and accidental hypothermia.<p><p> <i>Main body</i> - Evaluation of ECG-data from accidental and therapeutic hypothermia patients and experimental data on ECG ...
    • Pharmacodynamic properties for inhibition of cAMP- and cGMP elimination by pentoxifylline remain unaltered in vitro during hypothermia 

      Selli, Anders Lund; Kalasho, Adrina; Smaglyukova, Natalia; Kondratiev, Timofei; Fuskevåg, Ole Martin; Sager, Georg; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-15)
      Background - Rewarming from hypothermia is associated with severe complications, one of which is hypothermia-induced cardiac dysfunction. This condition is characterized by decreased cardiac output accompanied by increased total peripheral resistance. This contributes to mortality rate approaching 40%. Despite this, no pharmacological interventions are recommended for these patients below 30 °C. ...
    • Pharmacological Approaches To Management Of Hypothermia-Induced Cardiac Dysfunction 

      Dietrichs, Erik Sveberg (Doctoral thesis; Doktorgradsavhandling, 2015-03-20)
      We performed randomized, controlled experimental studies in an intact rat model and in isolated rat cardiomyocytes with the following aims: Paper I: To investigate the effects of epinephrine during hypothermia and after rewarming and determine hypothermia-induced effects on in vivo and in vitro cardiac β-receptor sensitivity. Paper II: To describe hemodynamic responses to the phosphodiesterase ...
    • Prediction of Ventricular Arrhythmias by QRS/QTc - Ratio in Citalopram or Escitalopram Intoxication 

      Dietrichs, Erik Sveberg; Smith, Godfrey L (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-16)
      <b><p>Background:</b> The U.S. Food and Drug Administration (FDA) has stated that citalopram and escitalopram should not be used at daily doses above 40 mg/20 mg due to risk for development of fatal ventricular arrhythmias like torsade de pointes (TdP). Yet, supratherapeutic serum concentrations of citalopram are common and predicting patients at risk for TdP is of high clinical value. Accordingly, ...
    • Pro-arrhythmic effect of escitalopram and citalopram at serum concentrations commonly observed in older patients – a study based on a cohort of 19,742 patients 

      Faraj, Pari; Størset, Elisabet; Hole, Kristine; Smith, Godfrey L; Molden, Espen; Dietrichs, Erik Sveberg (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-08-26)
      Background - For a decade, patients have been advised against using high citalopram- and escitalopram-doses due to risk for ventricular arrhythmia and cardiac arrest. Still, these drugs are widely used to treat depression and anxiety especially in older patients. It is unclear why they are cardiotoxic and at what serum concentrations patients are at risk for arrhythmias. Thus, how many patients that ...