Thomas Halvorsen

Dr. Thomas Halvorsen

orcid

Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
9 September 2017 in European Respiratory Journal
Verified
Journal Article
Open access
PDF file
THThomas Halvorsen
Thomas Halvorsen
EWEmil Schwarz Walsted
Emil Schwarz Walsted
CBCaterina Bucca
Caterina Bucca
ABAndrew Bush
Andrew Bush
GCGiovanna Cantarella
Giovanna Cantarella
JHJohn-Helge Heimdal
John-Helge Heimdal
Inducible laryngeal obstruction (ILO) describes an inappropriate, transient, reversible narrowing of the larynx in response to external triggers. ILO is an important cause of a variety of respiratory symptoms and can mimic asthma. Current understanding of ILO has been hampered by imprecise nomenclature and variable approaches to assessment and management. A task force of the European Respiratory Society (ERS) and European Laryngological Society (ELS) was thus set up to address this, and to identify research priorities.A literature search identified relevant articles published until June 2016, using all identifiable terms for ILO, although including only articles using laryngoscopy. In total, 172 out of 252 articles met the inclusion criteria, summarised in sections on diagnostic approach, aetiology, comorbidities, epidemiology and treatment. The consensus taxonomy published by ERS, ELS and the American College of Chest Physicians (ACCP) in 2015 is used throughout this statement.We highlight the high prevalence of ILO and the clinical impact for those affected. Despite recent advances, most aspects of this condition unfortunately remain incompletely understood, precluding firm guidance. Specifically, validated diagnostic and treatment algorithms are yet to be established, and no randomised control studies were identified in this search; hence we also make recommendations for future research.

2 January 2006 in The Laryngoscope
Verified
Journal Article
Closed access
PDF file
JHJohn‐Helge Heimdal
John‐Helge Heimdal
OROla D. Roksund
Ola D. Roksund
THThomas Halvorsen
Thomas Halvorsen
BSBritt T. Skadberg
Britt T. Skadberg
JOJan Olofsson
Jan Olofsson

7 June 2013 in Thorax
Verified
Journal Article
Closed access
PDF file
MVMaria Vollsæter
Maria Vollsæter
OROla Drange Røksund
Ola Drange Røksund
GEGeir Egil Eide
Geir Egil Eide
TMTrond Markestad
Trond Markestad
THThomas Halvorsen
Thomas Halvorsen
Background As a result of advances in perinatal care, more small preterm infants survive. There are concerns that preterm birth and its treatments may harm pulmonary development and thereby lead to chronic airway obstruction in adulthood. Objective To assess the development of spirometric lung function variables from mid-childhood to adulthood after extreme preterm birth. Methods Two population-based cohorts born at gestational age ≤28 weeks or with birth weight ≤1000 g performed lung function tests at 10 and 18 and at 18 and 25 years of age, respectively, together with matched term-born controls. The results are presented as z scores, normalised for age, sex and height. Longitudinal development was compared for groups born at term and preterm, split by a history of absence (n=20), mild (n=38) or moderate/severe (n=25) neonatal bronchopulmonary dysplasia (BPD). Results The preterm-born cohorts, particularly those with neonatal BPD, had significantly lower forced expiratory volume in 1 s and mid-expiratory flow than those born at term at all assessments (z scores in the range −0.40 to −1.84). Within each of the subgroups the mean z scores obtained over the study period were largely similar, coefficients of determination ranging from 0.64 to 0.82. The pattern of development for the BPD subgroups did not differ from each other or from the groups born at term (tests of interaction). Conclusions Airway obstruction was present from mid-childhood to adulthood after extreme preterm birth, most evident after neonatal BPD. Lung function indices were tracking similarly in the preterm and term-born groups.

26 September 2019 in European Respiratory Journal
Verified
Journal Article
Open access
PDF file
LDLiesbeth Duijts
Liesbeth Duijts
EMEvelien R. van Meel
Evelien R. van Meel
LMLaura Moschino
Laura Moschino
EBEugenio Baraldi
Eugenio Baraldi
MBMagda Barnhoorn
Magda Barnhoorn
MPMarielle W. Pijnenburg
Marielle W. Pijnenburg
This document provides recommendations for monitoring and treatment of children in whom bronchopulmonary dysplasia (BPD) has been established and who have been discharged from the hospital, or who were >36 weeks of postmenstrual age. The guideline was based on predefined Population, Intervention, Comparison and Outcomes (PICO) questions relevant for clinical care, a systematic review of the literature and assessment of the evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. After considering the balance of desirable (benefits) and undesirable (burden, adverse effects) consequences of the intervention, the certainty of the evidence, and values, the task force made conditional recommendations for monitoring and treatment of BPD based on very low to low quality of evidence. We suggest monitoring with lung imaging using ionising radiation in a subgroup only, for example severe BPD or recurrent hospitalisations, and monitoring with lung function in all children. We suggest to give individual advice to parents regarding daycare attendance. With regards to treatment, we suggest the use of bronchodilators in a subgroup only, for example asthma-like symptoms, or reversibility in lung function; no treatment with inhaled or systemic corticosteroids; natural weaning of diuretics by the relative decrease in dose with increasing weight gain if diuretics are started in the neonatal period; and treatment with supplemental oxygen with a saturation target range of 90–95%. A multidisciplinary approach for children with established severe BPD after the neonatal period into adulthood is preferable. These recommendations should be considered until new and urgently needed evidence becomes available.

31 August 2015 in European Respiratory Review
Verified
Journal Article
Open access
PDF file
PCPernille M. Christensen
Pernille M. Christensen
JHJohn-Helge Heimdal
John-Helge Heimdal
KCKent L. Christopher
Kent L. Christopher
CBCaterina Bucca
Caterina Bucca
GCGiovanna Cantarella
Giovanna Cantarella
JWJanet A. Wilson
Janet A. Wilson
Individuals reporting episodes of breathing problems caused by re-occurring variable airflow obstructions in the larynx have been described in an increasing number of publications, with more than 40 different terms being used without consensus on definitions. This lack of an international consensus on nomenclature is a serious obstacle for the development of the area, as knowledge from different centres cannot be matched, pooled or readily utilised by others. Thus, an international Task Force has been created, led by the European Respiratory Society/European Laryngological Society/American College of Chest Physicians. This review describes the methods used to reach an international consensus on the subject and the resulting nomenclature, the 2013 international consensus conference nomenclature.

1 August 2019 in The Lancet Respiratory Medicine
Verified
Journal Article
Open access
LDLex W Doyle
Lex W Doyle
SASture Andersson
Sture Andersson
ABAndy Bush
Andy Bush
JCJeanie L Y Cheong
Jeanie L Y Cheong
HCHege Clemm
Hege Clemm
EVElianne J L E Vrijlandt
Elianne J L E Vrijlandt
Maximal expiratory airflow peaks early in the third decade of life, then gradually declines with age. The pattern of airflow through adulthood for individuals born very preterm (at 2499 g) or at term. We did a meta-analysis of individual participant data from cohort studies, mostly from the pre-surfactant era. Studies were identified through the Adults born Preterm International Collaboration and by searching PubMed and Embase (search date May 25, 2016). Studies were eligible if they reported on expiratory flow rates beyond 16 years of age in individuals born very preterm or with very low birthweight, as well as controls born at term or with normal birthweight. Studies with highly selected cohorts (eg, only participants with bronchopulmonary dysplasia) or in which few participants were born very preterm or with very low birthweight were excluded. De-identified individual participant data from each cohort were provided by the holders of the original data to a central site, where all the data were pooled into one data file. Any data inconsistencies were resolved by discussion with the individual sites concerned. Individual participant data on expiratory flow variables (FEV1, forced vital capacity [FVC], FEV1/FVC ratio, and forced expiratory flow at 25-75% of FVC [FEF25-75%]) were converted to Z scores and analysed with use of generalised linear mixed models in a one-step approach. Of the 381 studies identified, 11 studies, comprising a total of 935 participants born very preterm or with very low birthweight and 722 controls, were eligible and included in the analysis. Mean age at testing was 21 years (SD 3·4; range 16-33). Mean Z scores were close to zero (as expected) in the control group, but were reduced in the very preterm or very low birthweight group for FEV1 (-0·06 [SD 1·03] vs -0·81 [1·33], mean difference -0·78 [95% CI -0·96 to -0·61], p<0·0001), FVC (-0·15 [0·98] vs -0·38 [1·18], -0·25 [-0·40 to -0·10], p=0·0012), FEV1/FVC ratio (0·14 [1·10] vs -0·64 [1·35], -0·74 [-0·85 to -0·64], p<0·0001), and FEF25-75% (-0·04 [1·10] vs -0·95 [1·47], -0·88 [-1·12 to -0·65], p<0·0001). Similar patterns were observed when we compared the proportions of individuals with values below the fifth percentile. Individuals born very preterm or with very low birthweight are at risk of not reaching their full airway growth potential in adolescence and early adulthood, suggesting an increased risk of chronic obstructive pulmonary disease in later adulthood. National Health and Medical Research Council (Australia), University of Bergen, Western Norway Regional Authority, National Institute for Health Research (UK), Stichting Astmabestrijding, St Olav's Hospital's Research Fund, Academy of Finland, European Commission, National Institute of Child Health and Human Development (USA), Victorian Government's Operational Infrastructure Support Program.