Publications 2024

Christensen VS, Skow M, Flottorp SA, Strømme H, Mdala I, Vallersnes OM (2024)
Immediate or delayed trial without catheter in acute urinary retention in males: A systematic review
BJUI Compass, 5 (8), 732-747
DOI 10.1002/bco2.369, PubMed 39157169

Dalaker VM, Furuhaugen H, Brekke M, Bjørnaas MA, Krpo M, Øiestad EL, Vallersnes OM (2024)
Drugs in blood and urine samples from victims of suspected exposure to drink spiking: A prospective observational study from Oslo, Norway
PLoS One, 19 (7), e0306191
DOI 10.1371/journal.pone.0306191, PubMed 38985694

Eick F, Vallersnes OM, Fjeld HE, Sørbye IK, Valberg M, Dahl C (2024)
Perinatal mortality among pregnant undocumented migrants in Norway 1999-2020: A register-based population study
Soc Sci Med, 353, 117055
DOI 10.1016/j.socscimed.2024.117055, PubMed 38897075

Tran JV, Brekke M, Vallersnes OM (2024)
Correction: Poisonings by substances of abuse at the Oslo Accident and Emergency Outpatient Clinic 2014-18
Tidsskr Nor Laegeforen, 144
DOI 10.4045/tidsskr.24.0489, PubMed 39319793

Vallersnes OM (2024)
The numbers speak
Tidsskr Nor Laegeforen, 144 (8)
DOI 10.4045/tidsskr.24.0291, PubMed 38934306

Vallersnes OM, Skow M, Christensen VS, Flottorp S (2024)
[Not Available]
Tidsskr Nor Laegeforen, 144 (8)
DOI 10.4045/tidsskr.24.0278, PubMed 38934316

Waters ML, Dargan PI, Yates C, Dines AM, Eyer F, Giraudon I, Heyerdahl F, Hovda KE, Liechti ME, Miró Ò, Vallersnes OM, Anseeuw K, Badaras R, Bitel M, Bonnici J, Brvar M, Caganova B, Calýskan F, Ceschi A, Chamoun K, Daveloose L, Galicia M, Gartner B, Gorozia K, Grenc D et al. (2024)
Clinical effects of cannabis compared to synthetic cannabinoid receptor agonists (SCRAs): a retrospective cohort study of presentations with acute toxicity to European hospitals between 2013 and 2020
Clin Toxicol (Phila), 62 (6), 378-384
DOI 10.1080/15563650.2024.2346125, PubMed 38934347

Publications 2023

Eick F, Vallersnes OM, Fjeld HE, Sørbye IK, Ruud SE, Dahl C (2023)
Use of emergency primary care among pregnant undocumented migrants over ten years: an observational study from Oslo, Norway
Scand J Prim Health Care, 41 (3), 317-325
DOI 10.1080/02813432.2023.2237074, PubMed 37485974

Harding A, Vallersnes OM, Carelli F, Kiknadze N, Karppinen H, Simmenroth A (2023)
European standards for undergraduate medical education in general practice; a blueprint - for action
Educ Prim Care, 34 (1), 2-6
DOI 10.1080/14739879.2022.2155997, PubMed 36730558

Noseda R, Franchi M, Pagnamenta A, Müller L, Dines AM, Giraudon I, Heyerdahl F, Eyer F, Hovda KE, Liechti ME, Miró Ò, Vallersnes OM, Yates C, Dargan PI, Wood DM, Ceschi A, Euro-DEN Research Group (2023)
Determinants of Admission to Critical Care Following Acute Recreational Drug Toxicity: A Euro-DEN Plus Study
J Clin Med, 12 (18)
DOI 10.3390/jcm12185970, PubMed 37762912

Prescott MG, Iakovleva E, Simpson MR, Pedersen SA, Munblit D, Vallersnes OM, Austad B (2023)
Intranasal analgesia for acute moderate to severe pain in children - a systematic review and meta-analysis
BMC Pediatr, 23 (1), 405
DOI 10.1186/s12887-023-04203-x, PubMed 37596559

Vallersnes OM (2023)
[After an overdose]
Tidsskr Nor Laegeforen, 143 (5)
DOI 10.4045/tidsskr.23.0163, PubMed 36987893

Vallersnes OM, Dines AM, Wood DM, Heyerdahl F, Hovda KE, Yates C, Giraudon I, Caganova B, Ceschi A, Galicia M, Liakoni E, Liechti ME, Miró Ò, Noseda R, Persett PS, Põld K, Schmid Y, Scholz I, Vigorita F, Dargan PI (2023)
Self-discharge during treatment for acute recreational drug toxicity: an observational study from emergency departments in seven European countries
Int J Emerg Med, 16 (1), 86
DOI 10.1186/s12245-023-00566-1, PubMed 38030969

Publications 2022

Crulli B, Dines AM, Blanco G, Giraudon I, Eyer F, Liechti ME, Miró Ò, Hovda KE, Heyerdahl F, Yates C, Vallersnes OM, Wood DM, Dargan PI, Euro-DEN Plus Research Group (2022)
Novel psychoactive substances-related presentations to the emergency departments of the European drug emergencies network plus (Euro-DEN plus) over the six-year period 2014-2019
Clin Toxicol (Phila), 60 (12), 1318-1327
DOI 10.1080/15563650.2022.2137524, PubMed 36322684

Eick F, Vallersnes OM, Fjeld HE, Sørbye IK, Storkås G, Ekrem M, Børmer M, Løberg SA, Ebbing C, Voldner N, Dahl C (2022)
Use of non-governmental maternity services and pregnancy outcomes among undocumented women: a cohort study from Norway
BMC Pregnancy Childbirth, 22 (1), 789
DOI 10.1186/s12884-022-05112-0, PubMed 36280826

Heier EC, Eyer F, Rabe C, Geith S, Dargan PI, Wood DM, Heyerdahl F, Dines AM, Giraudon I, Erik Hovda K, Yates C, Vallersnes OM, Miró Ò, Liechti ME, Zellner T, Euro-DEN Research Group (2022)
Clinical effect of ethanol co-use in patients with acute drug toxicity involving the use of central nervous system depressant recreational drugs
Eur J Emerg Med, 29 (4), 291-300
DOI 10.1097/MEJ.0000000000000932, PubMed 35404314

Ingebrigtsen E, Persett PS, Brekke M, Heyerdahl F, Hovda KE, Vallersnes OM (2022)
Poisoning with central stimulant drugs: an observational study from Oslo, Norway
Int J Emerg Med, 15 (1), 54
DOI 10.1186/s12245-022-00457-x, PubMed 36175843

Iqbal ZZ, Nguyen TMT, Brekke M, Vallersnes OM (2022)
Unspecified opioids among opioid overdoses in Oslo, Norway
BMC Res Notes, 15 (1), 134
DOI 10.1186/s13104-022-06022-2, PubMed 35397589

Johannessen TR, Halvorsen S, Atar D, Munkhaugen J, Nore AK, Wisløff T, Vallersnes OM (2022)
Cost-effectiveness of a rule-out algorithm of acute myocardial infarction in low-risk patients: emergency primary care versus hospital setting
BMC Health Serv Res, 22 (1), 1274
DOI 10.1186/s12913-022-08697-6, PubMed 36271364

Johannessen TR, Halvorsen S, Atar D, Vallersnes OM (2022)
Performance of the Novel Observation Group Criteria of the European Society of Cardiology (ESC) 0/1-Hour Algorithm in a Low-Risk Population
J Am Heart Assoc, 11 (7), e024927
DOI 10.1161/JAHA.121.024927, PubMed 35352564

Simmenroth A, Harding A, Vallersnes OM, Dowek A, Carelli F, Kiknadze N, Karppinen H (2022)
Early clinical exposure in undergraduate medical education: A questionnaire survey of 30 European countries
Med Teach, 45 (4), 426-432
DOI 10.1080/0142159X.2022.2137014, PubMed 36315584

Skjælaaen K, Nesvold H, Brekke M, Sare M, Landaas ET, Mdala I, Olsen AO, Vallersnes OM (2022)
Sexually transmitted infections among patients attending a sexual assault centre: a cohort study from Oslo, Norway
BMJ Open, 12 (12), e064934
DOI 10.1136/bmjopen-2022-064934, PubMed 36456026

Publications 2021

Johannessen TR, Atar D, Vallersnes OM, Larstorp ACK, Mdala I, Halvorsen S (2021)
Comparison of a single high-sensitivity cardiac troponin T measurement with the HEART score for rapid rule-out of acute myocardial infarction in a primary care emergency setting: a cohort study
BMJ Open, 11 (2), e046024
DOI 10.1136/bmjopen-2020-046024, PubMed 33627355

Klem N, Skjerven HO, Nilsen B, Brekke M, Vallersnes OM (2021)
Treatment for acute bronchiolitis before and after implementation of new national guidelines: a retrospective observational study from primary and secondary care in Oslo, Norway
BMJ Paediatr Open, 5 (1), e001111
DOI 10.1136/bmjpo-2021-001111, PubMed 34104804

Miró Ò, Waring WS, Dargan PI, Wood DM, Dines AM, Yates C, Giraudon I, Moughty A, O'Connor N, Heyerdahl F, Hovda KE, Vallersnes OM, Paasma R, Pold K, Jürgens G, Megarbane B, Anand JS, Liakoni E, Liechti M, Eyer F, Zacharov S, Caganova B, Bonnici J, Radenkova-Saeva J, Galicia M et al. (2021)
Variation of drugs involved in acute drug toxicity presentations based on age and sex: an epidemiological approach based on European emergency departments
Clin Toxicol (Phila), 59 (10), 896-904
DOI 10.1080/15563650.2021.1884693, PubMed 33724118

Tran JV, Brekke M, Vallersnes OM (2021)
Poisonings by substances of abuse at the Oslo Accident and Emergency Outpatient Clinic 2014-18
Tidsskr Nor Laegeforen, 141 (7)
DOI 10.4045/tidsskr.20.0751, PubMed 33950661

Tran JV, Brekke M, Vallersnes OM (2021)
Poisonings by substances of abuse at the Emergency Room in Oslo 2014-18
Tidsskr. Nor. Laegeforen., 141 (7), 646-651

Vibeto JH, Vallersnes OM, Dobloug A, Brekke M, Jacobsen D, Ekeberg Ø, Wangen KR (2021)
Treating patients with opioid overdose at a primary care emergency outpatient clinic: a cost-minimization analysis
Cost Eff Resour Alloc, 19 (1), 48
DOI 10.1186/s12962-021-00303-6, PubMed 34348747

Publications 2020

Andersson JA, Brekke M, Vallersnes OM (2020)
Acute poisoning from substance abuse of benzodiazepines
Tidsskr Nor Laegeforen, 140 (10)
DOI 10.4045/tidsskr.20.0035, PubMed 32602327

Andersson JA, Brekke M, Vallersnes OM (2020)
Acute intoxication by the drug-related use of benzodiazepines
Tidsskr. Nor. Laegeforen., 140 (10), 1027-1030

Aronsen AC, Brekke M, Vallersnes OM (2020)
Acute poisoning with gamma-hydroxybutyrate
Tidsskr Nor Laegeforen, 140 (10)
DOI 10.4045/tidsskr.19.0780, PubMed 32602311

Aronsen AC, Brekke M, Vallersnes OM (2020)
Acute intoxication with gamma hydroxybutyrate
Tidsskr. Nor. Laegeforen., 140 (10), 1023-1026

Johannessen TR, Vallersnes OM, Halvorsen S, Larstorp ACK, Mdala I, Atar D (2020)
Pre-hospital One-Hour Troponin in a Low-Prevalence Population of Acute Coronary Syndrome: OUT-ACS study
Open Heart, 7 (2)
DOI 10.1136/openhrt-2020-001296, PubMed 32719074

Miro O, Dargan PI, Galicia M, Anand JS, Bonnici J, Caganova B, Dines AM, Eyer F, Giraudon I, Heyerdahl F, Jurgens G, Kabata PM, Liakoni E, Liechti ME, Megarbane B, Moughty A, O'Connor N, Paasma R, Persett PS, Pold K, Radenkova-Saeva J, Scholz I, Vallersnes OM, Waring WS, Wood DM et al. (2020)
Authors' reply to comment on "Epidemiology, clinical features and management of patients presenting to European emergency departments with acute cocaine toxicity: comparison between powder cocaine and crack cocaine cases"
Clin. Toxicol., 58 (1), 72-74
DOI 10.1080/15563650.2019.1613549

Vallersnes OM (2020)
[The adversarial dialogue]
Tidsskr Nor Laegeforen, 140 (4)
DOI 10.4045/tidsskr.20.0076, PubMed 32192253

Vallersnes OM (2020)
The stingy conversation
Tidsskr. Nor. Laegeforen., 140 (4), 324

Publications 2019

Grimsrud MM, Brekke M, Syse VL, Vallersnes OM (2019)
Acute poisoning related to the recreational use of prescription drugs: an observational study from Oslo, Norway
BMC Emerg Med, 19 (1), 55
DOI 10.1186/s12873-019-0271-0, PubMed 31615421

Syse VL, Brekke M, Grimsrud MM, Persett PS, Heyerdahl F, Hovda KE, Vallersnes OM (2019)
Gender differences in acute recreational drug toxicity: a case series from Oslo, Norway
BMC Emerg Med, 19 (1), 29
DOI 10.1186/s12873-019-0244-3, PubMed 31035940

Vallersnes OM (2019)
Just drunkenness
Tidsskr Nor Laegeforen, 139 (13)
DOI 10.4045/tidsskr.19.0513, PubMed 31556530

Vallersnes OM (2019)
Just fill
Tidsskr. Nor. Laegeforen., 139 (13), 1224

Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2019)
Mortality and repeated poisoning after self-discharge during treatment for acute poisoning by substances of abuse: a prospective observational cohort study
BMC Emerg Med, 19 (1), 5
DOI 10.1186/s12873-018-0219-9, PubMed 30634924

Publications 2018

Grimhold TK, Skogstad L, Hafstad GS, Vallersnes OM, Ekeberg O (2018)
22 July 2011-psychological reactions in patients at the emergency room in Oslo
Tidsskr. Nor. Laegeforen., 138 (11), 1022-1028

Grimholt TK, Skogstad L, Hafstad GS, Vallersnes OM, Ekeberg Ø (2018)
[July 22, 2011 – psychological reactions in patients at the accident and emergency department in Oslo]
Tidsskr Nor Laegeforen, 138 (11)
DOI 10.4045/tidsskr.17.0132, PubMed 29947209

Miró Ò, Yates C, Dines AM, Wood DM, Dargan PI, Galán I, Jerez A, Puiguriguer J, Waring WS, Moughty A, O'Connor N, Heyerdahl F, Hovda KE, Vallersnes OM, Paasma R, Põld K, Jürgens G, Megarbane B, Anand JS, Liakoni E, Liechti M, Eyer F, Zacharov S, Caganova B, Giraudon I et al. (2018)
Emergencies related to recreational drug abuse in Spain compared to emergencies attended in 3 European areas
Emergencias, 30 (6), 385-394
PubMed 30638341

Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2018)
Mortality, morbidity and follow-up after acute poisoning by substances of abuse: A prospective observational cohort study
Scand J Public Health, 47 (4), 452-461
DOI 10.1177/1403494818779955, PubMed 29886813

Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2018)
Factors associated with rapidly repeated acute poisoning by substances of abuse: a prospective observational cohort study
BMC Res Notes, 11 (1), 724
DOI 10.1186/s13104-018-3834-3, PubMed 30314502

Publications 2017

Miró Ò, Galicia M, Dargan P, Dines AM, Giraudon I, Heyerdahl F, Hovda KE, Yates C, Wood DM, Liakoni E, Liechti M, Jürgens G, Pedersen CB, O'Connor N, Markey G, Moughty A, Lee C, O'Donohoe P, Sein Anand J, Puiguriguer J, Homar C, Eyer F, Vallersnes OM, Persett PS, Chevillard L et al. (2017)
Intoxication by gamma hydroxybutyrate and related analogues: Clinical characteristics and comparison between pure intoxication and that combined with other substances of abuse
Toxicol Lett, 277, 84-91
DOI 10.1016/j.toxlet.2017.05.030, PubMed 28579487

Vallersnes OM (2017)
The poisonings chart
Tidsskr Nor Laegeforen, 137 (12-13), 850
DOI 10.4045/tidsskr.17.0416, PubMed 28655248

Vallersnes OM (2017)
[Not Available]
Tidsskr Nor Laegeforen, 137 (12-13), 875
DOI 10.4045/tidsskr.17.0246, PubMed 28655265

Vallersnes OM, Persett PS, Øiestad EL, Karinen R, Heyerdahl F, Hovda KE (2017)
Underestimated impact of novel psychoactive substances: laboratory confirmation of recreational drug toxicity in Oslo, Norway
Clin Toxicol (Phila), 55 (7), 636-644
DOI 10.1080/15563650.2017.1312002, PubMed 28406320

Publications 2016

Vallersnes OM (2016)
[The art of medicine at out-of-hours services]
Tidsskr Nor Laegeforen, 136 (23-24), 2032-2033
DOI 10.4045/tidsskr.16.0181, PubMed 28004561

Vallersnes OM, Bjornaas MA, Lund C, Jacobsen D, Ekeberg Ø, Brekke M (2016)
Follow-up of young patients after acute poisoning by substances of abuse: a comparative cohort study at an emergency outpatient clinic
BMC Res Notes, 9, 398
DOI 10.1186/s13104-016-2200-6, PubMed 27506676

Vallersnes OM, Dines AM, Wood DM, Yates C, Heyerdahl F, Hovda KE, Giraudon I, Euro-DEN Research Group, Dargan PI (2016)
Psychosis associated with acute recreational drug toxicity: a European case series
BMC Psychiatry, 16, 293
DOI 10.1186/s12888-016-1002-7, PubMed 27538886

Vallersnes OM, Dines AM, Wood DM, Yates C, Heyerdahl F, Hovda KE, Giraudon I, Euro-DEN Research Group, Dargan PI (2016)
Erratum to: Psychosis associated with acute recreational drug toxicity: a European case series
BMC Psychiatry, 16 (1), 405
DOI 10.1186/s12888-016-1066-4, PubMed 27852244

Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2016)
Outpatient treatment of acute poisoning by substances of abuse: a prospective observational cohort study
Scand J Trauma Resusc Emerg Med, 24, 76
DOI 10.1186/s13049-016-0268-6, PubMed 27206472

Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2016)
Follow-up after acute poisoning by substances of abuse: a prospective observational cohort study
Scand J Prim Health Care, 34 (3), 309-316
DOI 10.1080/02813432.2016.1207152, PubMed 27404136

Publications 2015

Akopian M, Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2015)
Living conditions in the districts of Oslo and poisonings by substances of abuse treated at casualty clinic level
Tidsskr Nor Laegeforen, 135 (21), 1943-8
DOI 10.4045/tidsskr.15.0370, PubMed 26577320

Dalaker VM, Vallersnes OM, Fosshaug LE, Andersson KS, Hovda KE (2015)
A young woman who drank Strep test reagents
Tidsskr Nor Laegeforen, 135 (22), 2067-70
DOI 10.4045/tidsskr.15.0190, PubMed 26627296

Loose LM, Elde E, Aune MB, Vallersnes OM (2015)
Adolescent with respiratory impairments and short-lived fever
Tidsskr Nor Laegeforen, 135 (12-13), 1144-7
DOI 10.4045/tidsskr.14.1505, PubMed 26130549

Vallersnes OM, Jacobsen D, Ekeberg Ø, Brekke M (2015)
Patients presenting with acute poisoning to an outpatient emergency clinic: a one-year observational study in Oslo, Norway
BMC Emerg Med, 15, 18
DOI 10.1186/s12873-015-0045-2, PubMed 26268351

Publications 2012

Bhatti R, Solvik-Olsen T, Nordfalk KF, Vallersnes OM (2012)
[A young man with swallowing difficulties]
Tidsskr Nor Laegeforen, 132 (10), 1242-4
DOI 10.4045/tidsskr.11.0924, PubMed 22669386

Lund C, Vallersnes OM, Jacobsen D, Ekeberg O, Hovda KE (2012)
Outpatient treatment of acute poisonings in Oslo: poisoning pattern, factors associated with hospitalization, and mortality
Scand J Trauma Resusc Emerg Med, 20, 1
DOI 10.1186/1757-7241-20-1, PubMed 22217253

Publications 2009

Vallersnes OM, Lund C, Duns AK, Netland H, Rasmussen IA (2009)
Epidemic of poisoning caused by scopolamine disguised as Rohypnol tablets
Clin Toxicol (Phila), 47 (9), 889-93
DOI 10.3109/15563650903333804, PubMed 19821638

Publications 2000

Vallersnes OM, Halvorsen TF, Ommundsen OE (2000)
[To be on call during the New Year's Eve]
Tidsskr Nor Laegeforen, 120 (30), 3796-7
PubMed 11215963

Publications 1949

VALLERSNES O (1949)
[Overview of the congenital tear stenosis]
Nord Med, 41 (24), 1078
PubMed 18210543