Arild Erland Rønnestad

• Arribas, Cristina; Cavallaro, Giacomo; Gonzalez, Juan-Luis; Lagares, Carolina; Raffaeli, Genny & Smits, Anne [Vis alle 84 forfattere av denne artikkelen] (2024). Global cross-sectional survey on neonatal pharmacologic sedation and analgesia practices and pain assessment tools: impact of the sociodemographic index (SDI). Pediatric Research. ISSN 0031-3998. doi: 10.1038/s41390-024-03032-7.
• Server, Andrés; Latysheva, Anna; Nedregaard, Bård; Rønnestad, Arild Erland; Heiberg, Lise & Marthinsen, Pål Bache (2024). Perinatal Stroke as It is: Updates, Insights and Challenges. Neurographics. s. 1–17. doi: 10.3174/ng.2200042.
• Berisha, Gazmend; Kvenshagen, Line Norman; Boldingh, Anne Marthe; Nakstad, Britt; Blakstad, Elin Wahl & Rønnestad, Arild Erland [Vis alle 7 forfattere av denne artikkelen] (2023). Video-Recorded Airway Suctioning of Clear and Meconium-Stained Amniotic Fluid and Associated Short-Term Outcomes in Moderately and Severely Depressed Preterm and Term Infants. Children. ISSN 2227-9067. 11(1). doi: 10.3390/children11010016. Fulltekst i vitenarkiv Vis sammendrag

  Background: The aim of this study was to investigate delivery room airway suctioning and associated short-term outcomes in depressed infants. Methods: This is a single-centre prospective observational study of transcribed video recordings of preterm (gestational age, GA < 37 weeks) and term (GA ≥ 37 weeks) infants with a 5 min Apgar score ≤ 7. We analysed the association between airway suctioning, breathing, bradycardia and prolonged resuscitation (≥10 min). For comparison, non-suctioned infants with a 5 min Apgar score ≤ 7 were included. Results: Two hundred suction episodes were performed in 19 premature and 56 term infants. Breathing improved in 1.9% of premature and 72.1% of term infants, and remained unchanged in 84.9% of premature and 27.9% of term infants after suctioning. In our study, 61 (81.3%) preterm and term infants who were admitted to the neonatal intensive care unit experienced bradycardia after airway suctioning. However, the majority of the preterm and more than half of the term infants were bradycardic before the suction procedure was attempted. Among the non-airway suctioned infants (n = 26), 73.1% experienced bradycardia, with 17 non-airway suctioned infants being admitted to the neonatal intensive care unit. There was a need for resuscitation ≥ 10 min in 8 (42.1%) preterm and 32 (57.1%) term infants who underwent airway suctioning, compared to 2 (33.3%) preterm and 19 (95.0%) term infants who did not receive airway suctioning. Conclusions: In the infants that underwent suctioning, breathing improved in most term, but not preterm infants. More non-suctioned term infants needed prolonged resuscitation. Airway suctioning was not directly associated with worsening of breathing, bradycardia, or extended resuscitation needs.

• Huncikova, Zuzana; Stensvold, Hans Jørgen; Øymar, Knut Asbjørn Alexander; Vatne, Anlaug; Lang, Astri Maria & Støen, Ragnhild [Vis alle 12 forfattere av denne artikkelen] (2023). Variation in antibiotic consumption in very preterm infants-a 10 year population-based study. Journal of Antimicrobial Chemotherapy. ISSN 0305-7453. 79(1), s. 143–150. doi: 10.1093/jac/dkad358. Fulltekst i vitenarkiv
• Wik, Gunnar; Jortveit, Jarle; Sitras, Vasilis; Perminow, Karl Viktor; Pripp, Are Hugo & Døhlen, Gaute [Vis alle 8 forfattere av denne artikkelen] (2023). Detection of severe congenital heart defects in live-born infants in Norway 2017–2020. Acta Paediatrica. ISSN 0803-5253. 113(1), s. 135–142. doi: 10.1111/apa.16953.
• Norman, Mikael; Padkær Petersen, Jesper; Stensvold, Hans Jørgen; Thorkelsson, Thordur; Helenius, Kjell & Brix Andersson, Charlotte [Vis alle 17 forfattere av denne artikkelen] (2023). Preterm birth in the Nordic countries—Capacity, management and outcome in neonatal care. Acta Paediatrica. ISSN 0803-5253. 112(7), s. 1422–1433. doi: 10.1111/apa.16753. Fulltekst i vitenarkiv
• Brekke, Stine Marie; Halvorsen, Silje Torp; Bjørkvoll, Julie; Thorsby, Per Medbøe; Rønnestad, Arild Erland & Zykova, Svetlana [Vis alle 12 forfattere av denne artikkelen] (2023). The association between infant salivary cortisol and parental presence in the neonatal intensive care unit during and after COVID-19 visitation restrictions: A cross-sectional study. Early Human Development. ISSN 0378-3782. 182. doi: 10.1016/j.earlhumdev.2023.105788. Fulltekst i vitenarkiv
• Berisha, Gazmend; Boldingh, Anne Marthe; Nakstad, Britt; Blakstad, Elin Wahl; Rønnestad, Arild Erland & Solevåg, Anne Lee (2023). Retrospectively Assessed Muscle Tone and Skin Colour following Airway Suctioning in Video-Recorded Infants Receiving Delivery Room Positive Pressure Ventilation. Children. ISSN 2227-9067. 10(1). doi: 10.3390/children10010166. Fulltekst i vitenarkiv
• Ohnstad, Mari Oma; Stensvold, Hans Jørgen; Pripp, Are Hugo; Tvedt, Christine Raaen; Jelsness-Jørgensen, Lars-Petter & Astrup, Henriette [Vis alle 15 forfattere av denne artikkelen] (2023). Associations between unit workloads and outcomes of first extubation attempts in extremely premature infants below a gestational age of 26 weeks. Frontiers in pediatrics. ISSN 2296-2360. 11, s. 1–9. doi: 10.3389/fped.2023.1090701. Fulltekst i vitenarkiv Vis sammendrag

  Objective: The objective was to explore whether high workloads in neonatal intensive care units were associated with short-term respiratory outcomes of extremely premature (EP) infants born <26 weeks of gestational age. Methods: This was a population-based study using data from the Norwegian Neonatal Network supplemented by data extracted from the medical records of EP infants <26 weeks GA born from 2013 to 2018. To describe the unit workloads, measurements of daily patient volume and unit acuity at each NICU were used. The effect of weekend and summer holiday was also explored. Results: We analyzed 316 first planned extubation attempts. There were no associations between unit workloads and the duration of mechanical ventilation until each infant’s first extubation or the outcomes of these attempts. Additionally, there were no weekend or summer holiday effects on the outcomes explored. Workloads did not affect the causes of reintubation for infants who failed their first extubation attempt. Conclusion: Our finding that there was no association between the organizational factors explored and short-term respiratory outcomes can be interpreted as indicating resilience in Norwegian neonatal intensive care units.

• Huncikova, Zuzana; Vatne, Anlaug; Stensvold, Hans Jørgen; Lang, Astri Maria; Støen, Ragnhild & Brigtsen, Anne Karin [Vis alle 10 forfattere av denne artikkelen] (2023). Late-onset sepsis in very preterm infants in Norway in 2009-2018: A population-based study. Archives of Disease in Childhood: Fetal and Neonatal Edition. ISSN 1359-2998. 108(5). doi: 10.1136/archdischild-2022-324977. Fulltekst i vitenarkiv
• Stenersen, Eydis Oddsdottir; Olsen, Annette; Melheim, Maria; Solberg, Rønnaug; Dannevig, Ingrid & Schmölzer, Georg [Vis alle 11 forfattere av denne artikkelen] (2023). A Piglet Perinatal Asphyxia Model to Study Cardiac Injury and Hemodynamics after Cardiac Arrest, Resuscitation, and the Return of Spontaneous Circulation. Journal of Visualized Experiments. ISSN 1940-087X. 2023(191). doi: 10.3791/64788. Fulltekst i vitenarkiv Vis sammendrag

  Neonatal piglets have been extensively used as translational models for perinatal asphyxia. In 2007, we adapted a well-established piglet asphyxia model by introducing cardiac arrest. This enabled us to study the impact of severe asphyxia on key outcomes, including the time taken for the return of spontaneous circulation (ROSC), as well as the effect of chest compressions according to alternative protocols for cardiopulmonary resuscitation. Due to the anatomical and physiological similarities between piglets and human neonates, piglets serve as good models in studies of cardiopulmonary resuscitation and hemodynamic monitoring. In fact, this cardiac arrest model has provided evidence for guideline development through research on resuscitation protocols, pathophysiology, biomarkers, and novel methods for hemodynamic monitoring. Notably, the incidental finding that a substantial fraction of piglets have pulseless electrical activity (PEA) during cardiac arrest may increase the applicability of the model (i.e., it may be used to study pathophysiology extending beyond the perinatal period). However, the model generation is technically challenging and requires various skill sets, dedicated personnel, and a fine balance of the measures, including the surgical protocols and the use of sedatives/analgesics, to ensure a reasonable rate of survival. In this paper, the protocol is described in detail, as well as experiences with adaptations to the protocol over the years.

• Rød, Emma; Solberg, Vilde; Stenersen, Eydis Oddsdottir; Garberg, Håvard Tetlie; Mjelle, Anders Batman & Tølløfsrud, Per Arne [Vis alle 8 forfattere av denne artikkelen] (2022). Biochemical surveillance versus clinical observation of term infants born after prolonged rupture of membranes – A quality assurance initiative. Acta Paediatrica. ISSN 0803-5253. 112(3), s. 391–397. doi: 10.1111/apa.16617. Fulltekst i vitenarkiv Vis sammendrag

  Aim To examine whether biochemical surveillance vs clinical observation of term infants with prolonged rupture of membranes as a risk factor for early-onset sepsis is associated with differences in patient trajectories in maternity and neonatal intensive care units. Methods A retrospective study of live-born infants with gestational age ≥ 37 + 0 weeks born after prolonged rupture of membranes (≥24 h) in four Norwegian hospitals 2017–2019. Two hospitals used biochemical surveillance, and two used predominantly clinical observation to identify early-onset sepsis cases. Results The biochemical surveillance hospitals had more C-reactive protein measurements (p < 0.001), neonatal intensive care unit admissions (p < 0.001) and antibiotic treatment (p < 0.001). Hospitals using predominantly clinical observation initiated antibiotic treatment earlier in infants with suspected early-onset sepsis (p = 0.04) but not in infants fulfilling early-onset sepsis diagnostic criteria (p = 0.09). There was no difference in antibiotic treatment duration (p = 0.59), fraction of infants fulfilling early-onset sepsis diagnostic criteria (p = 0.49) or length of hospitalisation (p = 0.30), and no early-onset sepsis-related adverse outcomes. Conclusion The biochemical surveillance hospitals had more C-reactive protein measurements, but there was no difference in antibiotic treatment duration, early-onset sepsis cases, length of hospitalisation or adverse outcomes. Personnel resources needed for clinical surveillance should be weighed against the limitation of potentially painful procedures.

• Vatne, Anlaug; Hapnes, Nina; Stensvold, Hans Jørgen; Dalen, Ingvild; Guthe, Hans Jørgen Timm & Støen, Ragnhild [Vis alle 9 forfattere av denne artikkelen] (2022). Early empirical antibiotics and adverse clinical outcomes in infants born very preterm: A population-based cohort. Journal of Pediatrics. ISSN 0022-3476. s. 1–13. doi: 10.1016/j.jpeds.2022.09.029. Fulltekst i vitenarkiv
• Strømmen, Kenneth; Lyche, Jan Ludvig; Moltu, Sissel Jennifer; Müller, Mette Helen Bjørge; Blakstad, Elin Wahl & Brække, Kristin [Vis alle 12 forfattere av denne artikkelen] (2022). Estimated daily intake of phthalates, parabens, and bisphenol A in hospitalised very low birth weight infants . Chemosphere. ISSN 0045-6535. 309(Part 1). doi: 10.1016/j.chemosphere.2022.136687. Fulltekst i vitenarkiv
• Reigstad, Hallvard; Hufthammer, Karl Ove; Rønnestad, Arild Erland; Klingenberg, Claus Andreas; Stensvold, Hans Jørgen & Markestad, Trond Jacob (2022). Early surfactant and non-invasive ventilation versus intubation and surfactant: a propensity score-matched national study. BMJ Paediatrics Open. ISSN 2399-9772. 6(1). doi: 10.1136/bmjpo-2022-001527. Fulltekst i vitenarkiv Vis sammendrag

  Objective To compare outcome after less invasive surfactant administration (LISA) and primary endotracheal intubation (non-LISA) in infants born before gestational age (GA) 28 weeks. Setting All neonatal intensive care units (NICUs) in Norway during 2012–2018. Methods Defined population-based data were prospectively entered into a national registry. We compared LISA infants with all non-LISA infants and with non-LISA infants who received surfactant following intubation. We used propensity score (PS) matching to identify non-LISA infants who were similar regarding potential confounders. Main outcome variables Rate and duration of mechanical ventilation (MV), survival, neurological and gastrointestinal morbidity, and need of supplemental oxygen or positive pressure respiratory support at postmenstrual age (PMA) 36 and 40 weeks. Results We restricted analyses to GA 25–27 weeks (n=843, 26% LISA) because LISA was rarely used at lower GAs. There was no significant association between NICUs regarding proportions treated with LISA and proportions receiving MV. In the PS-matched datasets, fewer LISA infants received MV (61% vs 78%, p<0.001), and they had fewer days on MV (mean difference 4.1, 95% CI 0.0 to 8.2 days) and lower mortality at PMA 40 weeks (absolute difference 6%, p=0.06) compared with all the non-LISA infants, but only a lower rate of MV (64% vs 97%, p<0.001) and fewer days on MV (mean difference 5.8, 95% CI 0.6 to 10.9 days) compared with non-LISA infants who received surfactant after intubation. Conclusion LISA reduced the rate and duration of MV but had no other clear benefits. Data availability statement All data relevant to the study are included in the article or uploaded as supplementary information. Relevant data are included in text. Data files may be obtained from a third party and are not publicly available. http://creativecommons.org/licenses/by-nc/4.0/ This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

• Ohnstad, Mari Oma; Stensvold, Hans Jørgen; Pripp, Are Hugo; Tvedt, Christine Raaen; Jelsness-Jørgensen, Lars-Petter & Astrup, Henriette [Vis alle 15 forfattere av denne artikkelen] (2022). Predictors of extubation success: a population-based study of neonates below a gestational age of 26 weeks. BMJ Paediatrics Open. ISSN 2399-9772. 6(1), s. 1–7. doi: 10.1136/bmjpo-2022-001542. Fulltekst i vitenarkiv Vis sammendrag

  The aim of the study was to investigate first extubation attempts among extremely premature (EP) infants and to explore factors that may increase the quality of clinical judgement of extubation readiness. Design and method A population-based study was conducted to explore first extubation attempts for EP infants born before a gestational age (GA) of 26 weeks in Norway between 1 January 2013 and 31 December 2018. Eligible infants were identified via the Norwegian Neonatal Network database. The primary outcome was successful extubation, defined as no reintubation within 72 hours after extubation. Results Among 482 eligible infants, 316 first extubation attempts were identified. Overall, 173 (55%) infants were successfully extubated, whereas the first attempt failed in 143 (45%) infants. A total of 261 (83%) infants were extubated from conventional ventilation (CV), and 55 (17%) infants were extubated from high-frequency oscillatory ventilation (HFOV). In extubation from CV, pre-extubation fraction of inspired oxygen (FiO2) ≤0.35, higher Apgar score, higher GA, female sex and higher postnatal age were important predictors of successful extubation. In extubation from HFOV, a pre-extubation FiO2 level ≤0.35 was a relevant predictor of successful extubation. Conclusions The correct timing of extubation in EP infants is important. In this national cohort, 55% of the first extubation attempts were successful. Our results suggest that additional emphasis on oxygen requirement, sex and general condition at birth may further increase extubation success when clinicians are about to extubate EP infants for the first time.

• Rød, Irene; Jørstad, Anna-Kristi; Aagaard, Hanne; Rønnestad, Arild Erland & Solevåg, Anne Lee (2022). Advanced Clinical Neonatal Nursing Students’ Transfer of Performance: From Skills Training With Real-Time Feedback on Ventilation to a Simulated Neonatal Resuscitation Scenario. Frontiers in pediatrics. ISSN 2296-2360. 10, s. 1–11. doi: 10.3389/fped.2022.866775. Fulltekst i vitenarkiv
• Mundal, Håkon S.; Rønnestad, Arild Erland; Klingenberg, Claus Andreas; Stensvold, Hans Jørgen & Størdal, Ketil (2021). Antibiotic Use in Term and Near-Term Newborns . Pediatrics. ISSN 0031-4005. 148(6). doi: 10.1542/peds.2021-051339. Fulltekst i vitenarkiv
• Størdal, Eline Hasselgård; Solevåg, Anne Lee; Bjørnholt, Jørgen; Rønnestad, Arild Erland & Stensvold, Hans Jørgen (2021). Sepsis treatment options identified by 10-year study of microbial isolates and antibiotic susceptibility in a level-four neonatal intensive care unit. Acta Paediatrica. ISSN 0803-5253. doi: 10.1111/apa.16189. Fulltekst i vitenarkiv
• Berisha, Gazmend; Boldingh, Anne Marthe; Blakstad, Elin Wahl; Rønnestad, Arild Erlend & Solevåg, Anne Lee (2021). Management of the Unexpected Difficult Airway in Neonatal Resuscitation. Frontiers in pediatrics. ISSN 2296-2360. 9, s. 1–10. doi: 10.3389/fped.2021.699159.
• Wik, Gunnar; Jortveit, Jarle; Sitras, Vasilis; Døhlen, Gaute; Rønnestad, Arild Erlend & Holmstrøm, Henrik (2021). Unexpected death in children with severe congenital heart defects in Norway 2004-2016. Archives of Disease in Childhood. ISSN 0003-9888. 106, s. 961–966. doi: 10.1136/archdischild-2020-319936.
• Strømmen, Kenneth; Lyche, Jan Ludvig; Moltu, Sissel; Müller, Mette Helen Bjørge; Blakstad, Elin Wahl & Almaas, Astrid Nylander [Vis alle 12 forfattere av denne artikkelen] (2021). High urinary concentrations of parabens and bisphenol A in very low birth weight infants. Chemosphere. ISSN 0045-6535. 271, s. 1–9. doi: 10.1016/j.chemosphere.2021.129570. Fulltekst i vitenarkiv Vis sammendrag

  Very low birth weight infants (VLBW; birth weight < 1500 g) are treated with pharmaceuticals and medical equipment containing parabens and bisphenol A (BPA). Parabens are used in pharmaceuticals, whereas BPA in medical equipment where concentrations are rarely reported in hospitalised VLBW infants. We measured urinary concentrations of parabens and BPA and hypothesised high and increasing concentrations in infants born at lower gestational ages (GAs), and among infants with bronchopulmonary dysplasia (BPD) and late-onset septicaemia (LOS) due to higher exposure from pharmaceuticals and medical equipment. Urinary samples were collected during the first (n = 38) and fifth (n = 36) week of life. Methylparaben, ethylparaben, propylparaben, butylparaben, and BPA concentrations were measured using ultra high-performance liquid chromatography coupled to tandem mass spectrometry. VLBW infants had very high urinary concentrations of parabens and BPA compared to term infants and older children. The Σ paraben concentration was higher than detected in previous studies on premature infants. Lower GA at birth was associated with higher concentrations of parabens and BPA. Infants born before 28 weeks GA had higher first week concentrations of propylparaben (38.6 vs. 9.05 ng/mL, p = 0.007), butylparaben (0.28 vs. 0.09 ng/mL, p = 0.05) and fifth week concentrations of BPA (15.1 vs. 6.02 ng/mL, p = 0.02) than infants born after 28 weeks GA. Infants with LOS and BPD had higher fifth week concentrations of BPA than infants without LOS and BPD (LOS: 14.2 vs. 6.77 ng/mL, p = 0.07; BPD: 18.6 vs. 7.62 ng/mL, p = 0.05).

• Ohnstad, Mari Oma; Stensvold, Hans Jørgen; Tvedt, Christine Raaen & Rønnestad, Arild Erlend (2021). Duration of Mechanical Ventilation and Extubation Success among Extremely Premature Infants. Neonatology. ISSN 1661-7800. 118, s. 90–97. doi: 10.1159/000513329. Fulltekst i vitenarkiv
• Wik, Gunnar; Jortveit, Jarle; Sitras, Vasilis; Døhlen, Gaute; Rønnestad, Arild Erlend & Holmstrøm, Henrik (2020). Severe congenital heart defects: Incidence, causes and time trends of preoperative mortality in Norway. Archives of Disease in Childhood. ISSN 0003-9888. 105(8), s. 738–743. doi: 10.1136/archdischild-2019-317581.
• Strand, Janne Maren; Gul, Kiran Aftab; Erichsen, Hans Christian; Lundman, Emma; Berge, Mona C. & Trømborg, Anette Kjoshagen [Vis alle 28 forfattere av denne artikkelen] (2020). Second-Tier Next Generation Sequencing Integrated in Nationwide Newborn Screening Provides Rapid Molecular Diagnostics of Severe Combined Immunodeficiency. Frontiers in Immunology. ISSN 1664-3224. 11. doi: 10.3389/fimmu.2020.01417. Fulltekst i vitenarkiv
• Vatne, Anlaug; Klingenberg, Claus; Øymar, Knut; Rønnestad, Arild Erlend; Manzoni, Paolo & Rettedal, Siren (2020). Reduced antibiotic exposure by serial physical examinations in term neonates at risk of early-onset sepsis. The Pediatric Infectious Disease Journal. ISSN 0891-3668. 39(5), s. 438–443. doi: 10.1097/INF.0000000000002590.
• Blakstad, Elin Wahl; Korpela, Katri; Lee-Ødegård, Sindre; Nakstad, Britt; Moltu, Sissel & Strømmen, Kenneth [Vis alle 11 forfattere av denne artikkelen] (2019). Enhanced nutrient supply and intestinal microbiota development in very low birth weight infants. Pediatric Research. ISSN 0031-3998. doi: 10.1038/s41390-019-0412-x.
• de la Rosa-Carrillo, Daniel; Vindenes, Harald Bjarte; Kinsler, Veronica A; Rønnestad, Arild Erlend; Ringstad, Geir & Müller, Lil-Sofie Ording [Vis alle 10 forfattere av denne artikkelen] (2018). Aggressive melanoma in an infant with congenital melanocytic nevus syndrome and multiple, NRAS and BRAF mutation-negative nodules. Pediatric dermatology. ISSN 0736-8046. 35(5), s. e281–e285. doi: 10.1111/pde.13595. Fulltekst i vitenarkiv
• Korpela, Katri; Blakstad, Elin Wahl; Moltu, Sissel; Strømmen, Kenneth; Nakstad, Britt & Rønnestad, Arild Erlend [Vis alle 10 forfattere av denne artikkelen] (2018). Intestinal microbiota development and gestational age in preterm neonates. Scientific Reports. ISSN 2045-2322. 8:2453, s. 1–9. doi: 10.1038/s41598-018-20827-x. Fulltekst i vitenarkiv
• Stensvold, Hans Jørgen; Lang, Astri Maria; Strømmen, Kenneth; Abrahamsen, Tore G; Øglænd, Bjørn Edvin & Pripp, Are Hugo [Vis alle 7 forfattere av denne artikkelen] (2017). Strictly controlled glucose infusion rates are associated with a reduced risk of hyperglycaemia in extremely low birth weight preterm infants. Acta Paediatrica. ISSN 0803-5253. 107(3), s. 442–449. doi: 10.1111/apa.14164.
• Klitkou, Søren Toksvig; Iversen, Tor; Stensvold, Hans Jørgen & Rønnestad, Arild Erlend (2017). Use of hospital-based health care services among children aged 1 through 9 years who were born very preterm - a population-based study. BMC Health Services Research. ISSN 1472-6963. 17:571(571), s. 1–13. doi: 10.1186/s12913-017-2498-3. Fulltekst i vitenarkiv
• Strømmen, Kenneth; Haag, Alexander; Moltu, Sissel; Veierød, Marit Bragelien; Blakstad, Elin Wahl & Nakstad, Britt [Vis alle 12 forfattere av denne artikkelen] (2017). Enhanced nutrient supply to very low birth weight infants is associated with higher blood amino acid concentrations and improved growth. Clinical Nutrition ESPEN. ISSN 2405-4577. 18, s. 16–22. doi: 10.1016/j.clnesp.2017.01.003.
• Stensvold, Hans Jørgen; Klingenberg, Claus; Støen, Ragnhild; Moster, Dag; Brække, Kristin & Guthe, Hans Jørgen Timm [Vis alle 10 forfattere av denne artikkelen] (2017). Neonatal morbidity and 1-year survival of extremely preterm infants. Pediatrics. ISSN 0031-4005. 139(3). doi: 10.1542/peds.2016-1821.
• Blakstad, Elin Wahl; Moltu, Sissel; Nakstad, Britt; Veierød, Marit Bragelien; Strømmen, Kenneth & Juliusson, Petur Benedikt [Vis alle 11 forfattere av denne artikkelen] (2016). Enhanced nutrition improves growth and increases blood adiponectin concentrations in very low birth weight infants :. Food & Nutrition Research (FNR). ISSN 1654-6628. 60:33171, s. 1–11. doi: 10.3402/fnr.v60.33171.
• Burns, Margrete Larsen; Stensvold, Hans Jørgen; Risnes, Kari Ravndal; Guthe, Hans Jørgen Timm; Astrup, Henriette & Nordhov, Solveig Marianne [Vis alle 9 forfattere av denne artikkelen] (2016). Inotropic Therapy in Newborns, A Population-Based National Registry Study. Pediatric Critical Care Medicine. ISSN 1529-7535. 17(10), s. 948–956. doi: 10.1097/PCC.0000000000000898.
• Strømmen, Kenneth; Lyche, Jan Ludvig; Blakstad, Elin Wahl; Moltu, Sissel; Veierød, Marit Bragelien & Almaas, Astrid [Vis alle 13 forfattere av denne artikkelen] (2016). Increased levels of phthalates in very low birth weight infants with septicemia and bronchopulmonary dysplasia. Environment International. ISSN 0160-4120. 89-90, s. 228–234. doi: 10.1016/j.envint.2016.01.024.
• Fjalstad, Jon Widding; Stensvold, Hans Jørgen; Bergseng, Håkon; Simonsen, Gunnar Skov; Salvesen, Bodil & Rønnestad, Arild Erlend [Vis alle 7 forfattere av denne artikkelen] (2016). Early-Onset Sepsis and Antibiotic Exposure in Term Infants: A Nationwide Population-Based Study in Norway. The Pediatric Infectious Disease Journal. ISSN 0891-3668. 35(1), s. 1–6. doi: 10.1097/INF.0000000000000906. Vis sammendrag

  Background: Sepsis is a leading cause of neonatal morbidity and mortality. Clinical suspicion may lead to overuse of antibiotics. The objective of this study was to assess the epidemiology of early-onset sepsis (EOS) and antibiotic exposure during the first week of life in Norwegian term infants. Methods: This is a nationwide population-based study from the Norwegian Neonatal Network. During the 3-year study period (2009–2011), 20 of Norway’s 21 neonatal units prospectively collected data. Among 168,877 live-born (LB) term infants born during the study period, 10,175 (6.0%) infants were hospitalized in the first week of life and included in the study. Results: There were 91 cases of culture-confirmed EOS (0.54 per 1000 LB) and 1447 cases classified as culture-negative EOS (8.57 per 1000 LB). The majority of culture-confirmed EOS cases were caused by Gram-positives (83/91; 91%), most commonly group B streptococci (0.31 per 1000 LB). Intravenous antibiotics were administered to 3964 infants; 39% of all admissions and 2.3% of all LB term infants. Empiric therapy consisted of an aminoglycoside and either benzylpenicillin or ampicillin in 95% of the cases. The median (interquartile range) treatment duration was 8 (7–10) days for culture-confirmed EOS and 6 (5–7) days for culture-negative EOS. There was 1 EOS-attributable death (group B streptococcal EOS) during the study period. Conclusions: In this registry-based study, the incidence of culture-confirmed EOS was in line with previous international reports and the mortality was very low. A large proportion of infants without infection were treated with antibiotics. Measures should be taken to spare neonates unnecessary antibiotic treatment. Worldwide, invasive neonatal infections caused approximately 22% of the estimated 2.9 million neonatal deaths in 2012.1 Rates of infection and mortality vary by geographical region. In industrialized countries, the incidence of early-onset sepsis (EOS) in term infants currently ranges between 0.5 and 1.2 per 1000 live births, with a declining rate over the last 20 years.2–4 However, EOS is still a leading cause of mortality and morbidity in this population.3,5 Presenting clinical symptoms are nonspecific, and specific biomarkers are lacking.6,7 Clinical suspicion of EOS, therefore, frequently leads to admission to a neonatal unit and to empirical antibiotic therapy in many infants who do not have infections.8 Antibiotics may be lifesaving for the few infants who are truly infected, but overuse of broad-spectrum antibiotics increases the risk of colonization with resistant bacteria.9 Current evidence also suggests that antibiotic exposure in the neonatal period, and subsequent alteration of the gut flora, may predispose individuals to atopic diseases, asthma, obesity and other adverse outcomes.10–15 There are few registry-based studies reporting detailed epidemiological data on infection rates and antibiotic treatment in term infants.3,4,16,17 Some reports contain information from tertiary care units, making it difficult to examine population-based trends.3,16,17 Several multicentre studies examine predominantly preterm infants who constitute a high-risk group for nosocomial late-onset sepsis.18–20 The primary aim of this study was to investigate the epidemiology of EOS and exposure to systemic antibiotics during the first week of life in an unselected national cohort of live-born (LB) term infants and second to assess regional variations in infection rates, antibiotic use and outcome.

• Stensvold, Hans Jørgen; Strømmen, Kenneth; Lang, Astri Maria; Abrahamsen, Tore G; Steen, Eline Kjørsvik & Pripp, Are Hugo [Vis alle 7 forfattere av denne artikkelen] (2015). Early enhanced parenteral nutrition, hyperglycemia, and death among extremely low-birth-weight infants. JAMA pediatrics. ISSN 2168-6203. 169(11), s. 1003–1010. doi: 10.1001/jamapediatrics.2015.1667. Vis sammendrag

  Importance Efforts to optimize early parenteral nutrition (PN) in extremely low-birth-weight (ELBW) infants to promote growth and development may increase hyperglycemia risk. Recent studies have identified an association between early hyperglycemia and adverse outcomes in ELBW infants. Objectives To examine the prevalence of early hyperglycemia and clinical outcomes among ELBW infants before (2002-2005) and after (2006-2011) the implementation of an early enhanced PN protocol and to assess the independent effects of early enhanced PN and early hyperglycemia on mortality. Design, Setting, and Participants Observational cohort study in a level III neonatal intensive care unit. Prospectively collected clinical data in the neonatal intensive care unit’s medical database, nutritional information, and blood glucose levels were merged for analysis. All ELBW infants born between January 1, 2002, and December 31, 2011, without lethal malformations and still alive at 12 hours of life were eligible for inclusion in the study. Main Outcomes and Measures Mortality was the main outcome measure. Severe hyperglycemia was defined as 2 consecutive blood glucose levels exceeding 216 mg/dL at least 3 hours apart. A multivariable logistic regression model was applied to determine the independent effects of early enhanced PN and hyperglycemia on mortality. Results In total, 343 infants were included in the study, 129 in a historical comparison group before the enhanced PN protocol and 214 in the early enhanced PN group. Baseline characteristics were similar between the study groups. After the introduction of early enhanced PN, the prevalence of severe hyperglycemia during the first week of life was higher in the early enhanced PN group (11.6% [15 of 129] vs 41.6% [89 of 214], P < .001), as was the mortality (10.9% [14 of 129] vs 24.3% [52 of 214], P = .003). When adjusting for background characteristics, treatment, and nutritional data, early severe hyperglycemia remained a strong independent risk factor for death (odds ratio, 4.68; 95% CI, 1.82-12.03), together with gestational age (odds ratio, 0.62; 95% CI, 0.49-0.79). Conclusions and Relevance The implementation of an enhanced PN protocol was correlated with an increased prevalence of severe hyperglycemia and higher mortality. In the multivariable analysis, an enhanced PN regimen per se was not predictive of mortality, whereas early severe hyperglycemia remained strongly predictive of death. To avoid detrimental effects on outcomes in ELBW infants, the optimal composition of early PN to avoid postnatal growth failure must be carefully balanced against hyperglycemia risk.

• Blakstad, Elin Wahl; Strømmen, Kenneth; Moltu, Sissel; Wattam-Bell, John; Nordheim, Trond & Almaas, Astrid [Vis alle 15 forfattere av denne artikkelen] (2015). Improved visual perception in very low birth weight infants on enhanced nutrient supply. Neonatology. ISSN 1661-7800. 108(1), s. 30–37. doi: 10.1159/000381660.
• Stray-Pedersen, Asbjørg; Backe, Paul Hoff; Sorte, Hanne Sørmo; Mørkrid, Lars; Chokshi, N.Y. & Erichsen, Hans Christian [Vis alle 39 forfattere av denne artikkelen] (2014). PGM3 mutations cause a congenital disorder of glycosylation with severe immunodeficiency and skeletal dysplasia. American Journal of Human Genetics. ISSN 0002-9297. 95(1), s. 96–107. doi: 10.1016/j.ajhg.2014.05.007.
• Strømmen, Kenneth; Blakstad, Elin Wahl; Moltu, Sissel; Almaas, Astrid; Westerberg, Ane Cecilie & Amlien, Inge [Vis alle 16 forfattere av denne artikkelen] (2014). Enhanced Nutrient Supply to Very Low Birth Weight Infants is Associated with Improved White Matter Maturation and Head Growth. Neonatology. ISSN 1661-7800. 107(1), s. 68–75. doi: 10.1159/000368181.
• Moltu, Sissel; Sachse, Daniel; Blakstad, Elin Wahl; Strømmen, Kenneth; Nakstad, Britt & Almaas, Astrid [Vis alle 14 forfattere av denne artikkelen] (2014). Urinary metabolite profiles in premature infants show early postnatal metabolic adaption and maturation. Nutrients. ISSN 2072-6643. 6(5), s. 1913–1930. doi: 10.3390/nu6051913.
• Moltu, Sissel; Blakstad, Elin Wahl; Strømmen, Kenneth; Almaas, Astrid; Nakstad, Britt & Rønnestad, Arild Erlend [Vis alle 11 forfattere av denne artikkelen] (2014). Enhanced feeding and diminished postnatal growth failure in very-low-birth-weight infants - a randomized, controlled trial. Journal of Pediatric Gastroenterology and Nutrition - JPGN. ISSN 0277-2116. 58(3), s. 344–351. doi: 10.1097/MPG.0000000000000220.
• Moltu, Sissel; Strømmen, Kenneth; Blakstad, Elin Wahl; Almaas, Astrid; Westerberg, Ane Cecilie & Brække, Kristin [Vis alle 13 forfattere av denne artikkelen] (2013). Enhanced feeding in very-low-birth-weight infants may cause electrolyte disturbances and septicemia - A randomized, controlled trial. Clinical Nutrition. ISSN 0261-5614. 32(2), s. 207–212. doi: 10.1016/j.clnu.2012.09.004.
• Mitra, Souvik; Rønnestad, Arild Erlend & Holmstrøm, Henrik (2013). Management of patent ductus arteriosus in preterm infants - where do we stand? Congenital Heart Disease. ISSN 1747-079X. 8(6), s. 500–512. doi: 10.1111/chd.12143.
• Tandberg, Bente Silnes; Sandtrø, Hege Pettersen; Vårdal, Mari H & Rønnestad, Arild Erlend (2013). Parents of preterm evaluation of stress and nursing support. Journal of Neonatal Nursing. ISSN 1355-1841. 19(6), s. 317–326. doi: 10.1016/j.jnn.2013.01.008.
• Leversen, Katrine Tyborg; Sommerfelt, Kristian; Rønnestad, Arild Erlend; Kaaresen, Per Ivar; Farstad, Teresa & Skranes, Janne Helen [Vis alle 12 forfattere av denne artikkelen] (2011). Prediction of Neurodevelopmental and Sensory Outcome at 5 Years in Norwegian Children Born Extremely Preterm. Pediatrics. ISSN 0031-4005. 127(3), s. E630–E638. doi: 10.1542/peds.2010-1001.
• Granslo, Hildegunn Norbakken; Klingenberg, Claus; Aarag, Elizabeth; Rønnestad, Arild Erlend; Mollnes, Tom Eirik & Flægstad, Trond (2010). Arginine Catabolic Mobile Element Is Associated With Low Antibiotic Resistance and Low Pathogenicity in Staphylococcus epidermidis From Neonates. Pediatric Research. ISSN 0031-3998. 68(3), s. 237–241. doi: 10.1203/PDR.0b013e3181eb01e0.
• Leversen, Katrine Tyborg; Sommerfelt, Kristian; Rønnestad, Arild Erlend; Kaaresen, Per Ivar; Farstad, Teresa & Skranes, Janne Helen [Vis alle 12 forfattere av denne artikkelen] (2010). Predicting neurosensory disabilities at two years of age in a national cohort of extremely premature infants. Early Human Development. ISSN 0378-3782. 86(9), s. 581–586. doi: 10.1016/j.earlhumdev.2010.07.009.
• Westerberg, Ane C.; Henriksen, Christine; Ellingvåg, Asta; Veierød, Marit Bragelien; Juliusson, Petur & Nakstad, Britt [Vis alle 11 forfattere av denne artikkelen] (2010). First year growth among very low birth weight infants. Acta Paediatrica. ISSN 0803-5253. 99(4), s. 556–562. doi: 10.1111/j.1651-2227.2009.01667.x.
• Wold, Siw-Helen Westby; Sommerfelt, Kristian; Reigstad, Hallvard; Rønnestad, Arild; Medbø, Sverre & Farstad, Teresa [Vis alle 11 forfattere av denne artikkelen] (2009). Neonatal mortality and morbidity in extremely preterm small for gestational age infants: a population based study. Archives of Disease in Childhood: Fetal and Neonatal Edition. ISSN 1359-2998. 94(5), s. F363–F367. doi: 10.1136/adc.2009.157800.
• Henriksen, Christine; Westerberg, Ane Cecilie; Rønnestad, Arild Erlend; Nakstad, Britt; Veierød, Marit Bragelien & Drevon, Christian A [Vis alle 7 forfattere av denne artikkelen] (2009). Growth and nutrient intake among very-low-birth-weight infants fed fortified human milk during hospitalisation. British Journal of Nutrition. ISSN 0007-1145. 102(8), s. 1179–1186. doi: 10.1017/S0007114509371755.
• Henriksen, Christine; Haugholt, Kristin; Lindgren, Magnus; Aurvåg, Anne Karin; Rønnestad, Arild & Ronnestad, A [Vis alle 15 forfattere av denne artikkelen] (2008). Improved cognitive development among preterm infants attributable to early supplementation of human milk with docosahexaenoic acid and arachidonic acid. Pediatrics. ISSN 0031-4005. 121(6), s. 1137–1145. doi: 10.1542/peds.2007-1511. Vis sammendrag

  OBJECTIVE: The objective of our study was to evaluate the effect of supplementation with docosahexaenoic acid and arachidonic acid for human milk-fed preterm infants. The primary end point was cognitive development at 6 months of age. METHODS: The study was a randomized, double-blind, placebo-controlled study among 141 infants with birth weights of <1500 g. The intervention with 32 mg of docosahexaenoic acid and 31 mg of arachidonic acid per 100 mL of human milk started 1 week after birth and lasted until discharge from the hospital (on average, 9 weeks). Cognitive development was evaluated at 6 months of age by using the Ages and Stages Questionnaire and event-related potentials, a measure of brain correlates related to recognition memory. RESULTS: There was no difference in adverse events or growth between the 2 groups. At the 6-month follow-up evaluation, the intervention group performed better on the problem-solving subscore, compared with the control group (53.4 vs 49.5 points). There was also a nonsignificant higher total score (221 vs 215 points). The event-related potential data revealed that infants in the intervention group had significantly lower responses after the standard image, compared with the control group(8.6 vs 13.2). There was no difference in responses to novel images. CONCLUSIONS: Supplementation with docosahexaenoic acid and arachidonic acid for very preterm infants fed human milk in the early neonatal period was associated with better recognition memory and higher problem-solving scores at 6 months.

• Saugstad, Ola Didrik; Hansen, Thor Willy ; Rønnestad, Arild Erlend; Nakstad, Britt; Tølløfsrud, Per Arne & Reinholt, Finn P. [Vis alle 12 forfattere av denne artikkelen] (2007). Novel mutations in the gene encoding ATP binding cassette protein member A3 (ABCA3) resulting in fatal neonatal lung disease. Acta Paediatrica. ISSN 0803-5253. 96, s. 185–190. doi: 10.1111/j.1651-2227.2007.00016.x. Vis sammendrag

  Aim: To investigate whether intractable respiratory distress syndrome in three Norwegian term infants was due to mutations in the ABCA3 gene. Methods: The genes encoding SP-B (SFTPB), SP-C (SFTPC), and ABCA3 (ABCA3) were sequenced from the parents of one infant and two unrelated infants with fatal neonatal lung disease. Lung tissue was examined by histology, immunohistochemistry and electron microscopy. Results: Novel ABCA3 mutations were identified in each family. One patient had a phenotype differing from previous descriptions of this disease with an initial uneventful period. The diagnosis was established 19 years after death by analysing DNA material from the parents, with an ABCA3 mutation identified on one allele in each parent. The other two infants had more typical clinical courses with the onset of respiratory symptoms immediately after birth. ABCA3 mutations were identified on both alleles from these two infants, and electron microscopy of alveolar type 2 cells demonstrated abnormal lamellar body formation characteristic of this disorder. Conclusion: ABCA3 mutations were the basis for lung disease in all three patients. Children with lung disease due to ABCA3 deficiency may not have symptoms at birth. The finding of five novel mutations indicates allelic heterogeneity for ABCA3 mutations within the Norwegian population

• Klingenberg, Claus; Rønnestad, A; Anderson, A S; Abrahamsen, TG; Zorman, J & Villaruz, A [Vis alle 10 forfattere av denne artikkelen] (2007). Persistent strains of coagulase-negative staphylococci in a neonatal intensive care unit: virulence factors and invasiveness. Clinical Microbiology and Infection (CMI). ISSN 1198-743X. 13, s. 1100–1111. doi: 10.1111/j.1469-0691.2007.01818.x.
• Rønnestad, Arild Erlend; Abrahamsen, Tore G; Medbø, Sverre; Reigstad, Hallvard; Lossius, Kristin & Kaaresen, Per Ivar [Vis alle 9 forfattere av denne artikkelen] (2005). Septicemia in the First Week of Life in a Norwegian National Cohort of Extremely Premature Infants. Pediatrics. ISSN 0031-4005. 115(3), s. 262–268. Vis sammendrag

  OBJECTIVES.: To investigate the incidence, causes, predictors, and outcomes of septicemia in the first week of life in a national cohort of extremely premature infants. METHODS.: A prospective study of survival of all infants with gestational age of <28 weeks or birth weight of <1000 g who were born in Norway in 1999�2000 was performed. Data on the maternal prenatal history, delivery, and neonatal course, including detailed information on episodes of microbiologically verified septicemia, were collected on predefined forms. Septicemia was reported in 2 groups, ie, episodes diagnosed on the day of delivery (ie, very early-onset septicemia [VEOS]) and episodes diagnosed from day 2 to day 7 of life (ie, early-onset septicemia [EOS]). Logistic regression models were used for the selection of variables for predictor analysis in each group. RESULTS.: Of 462 included infants, VEOS occurred for 15 (32.5 per 1000 population) and EOS for 15 (35.5 per 1000 population). The most prevalent bacteria were Escherichia coli in VEOS (n = 9) and staphylococci (coagulase-negative staphylococci and Staphylococcus aureus) (n = 15) in EOS. Case fatality rates were 40% and 13%, respectively. Independent predictive factors for VEOS were clinical chorioamnionitis (odds ratio [OR]: 10.5; 95% confidence interval [CI]: 3.3-33.4) and high maternal age (OR: 1.2; 95% CI: 1.0-1.3), whereas not receiving systemic antibiotic therapy within 2 days of age (OR: 13.6; 95% CI: 3.7-50.2) and receiving nasal continuous positive airway pressure (n-CPAP) support at 24 hours of age (OR: 9.8; 95% CI: 2.5-38.4) independently predicted septicemia after the first day of life. CONCLUSIONS.: Whereas vertically transmitted septicemia was dominated by Gram-negative bacteria, with predictors being exclusively of maternal origin, EOS was dominated by typically nosocomial flora, with n-CPAP treatment at 24 hours of age being a powerful predictor. Early n-CPAP treatment, as opposed to mechanical ventilation, as a powerful predictor of septicemia in the early neonatal period, even with adjustment for early systemic antibiotic treatment, is a new observation among extremely premature infants that warrants additional study. Key Words: early-onset septicemia � neonatal septicemia � population-based study � prospective study � very low birth weight � extreme prematurity � predictor analysis � logistic regression Abbreviations: GA, gestational age � BW, birth weight � n-CPAP, nasal continuous positive airway pressure � VEOS, very early-onset septicemia � EOS, early-onset septicemia � CRIB, Clinical Risk Index for Babies � FSC, forward stepwise conditional � OR, odds ratio � CI, confidence interval � VLBW, very low birth weight � CONS, coagulase-negative staphylococci � IQR, interquartile range

• Rønnestad, Arild Erlend; Abrahamsen, Tore G; Medbø, Sverre; Reigstad, Hallvard; Lossius, Kristin & Kaaresen, Per Ivar [Vis alle 10 forfattere av denne artikkelen] (2005). Late-Onset Septicemia in a Norwegian National Cohort of Extremely Premature Infants Receiving Very Early Full Human Milk Feeding. Pediatrics. ISSN 0031-4005. 115(3), s. 269–275. Vis sammendrag

  OBJECTIVES.: To investigate the occurrence of and risk factors for late-onset septicemia (LOS) in a national cohort of extremely premature infants who received very early full human milk feeding. METHODS.: A prospective study of all infants born in Norway in 1999 and 2000 with gestational age of <28 weeks or birth weight of <1000 g was performed. Extensive clinical information, including data on feeding practices and episodes of septicemia, was collected on predefined forms. LOS was defined as growth of bacteria or fungi in blood cultures in conjunction with clinical symptoms consistent with systemic infection occurring after day 6 of life. Cox regression models, including models allowing for time-dependent covariates, were applied in the analysis of LOS. RESULTS.: Of 464 eligible infants, 462 (99.6%) were enrolled and 405 (87.7%) survived until day 7. LOS was diagnosed for 80 (19.7%). The predominant pathogens were coagulase-negative staphylococci, followed by Candida spp. Case fatality rates associated with septicemia were 10% in general and 43% for Candida spp septicemia. Necrotizing enterocolitis or bowel perforation was diagnosed for 19 infants (4%). Enteral feeding with human milk was initiated within the third day for 98% of patients, and 92% were receiving full enteral feeding (FEF) with human milk within the third week. Both high Clinical Risk Index for Babies scores and an umbilical venous catheter in situ at 7 days of age significantly predicted LOS. However, the overall most influential risk factor for LOS was the number of days without establishment of FEF with human milk, with an adjusted relative risk of 3.7 (2.0�6.9) for LOS if FEF was not established within the second week of life. CONCLUSIONS.: The incidence and case fatality rate of septicemia for this cohort of extremely preterm infants were lower than values in comparable studies. The main difference, compared with other studies, was the feeding practice, and the data suggest that very early FEF with human milk significantly reduces the risk of LOS among extremely premature infants

• Markestad, Trond; Kaaresen, Per Ivar; Rønnestad, Arild Erlend; Reigstad, Hallvard; Lossius, Kristin & Medbø, Sverre [Vis alle 10 forfattere av denne artikkelen] (2005). Early Death, Morbidity, and Need of Treatment Among Extremely Premature Infants. Pediatrics. ISSN 0031-4005. 115(5), s. 1289–1298. doi: 10.1542/peds.2004-1482. Vis sammendrag

  Objective. To determine outcomes, in terms of perinatal and early death, need for treatment, and morbidity at the time of discharge home, among extremely preterm infants. Design. A prospective observational study of all infants with a gestational age (GA) of 22 to 27 completed weeks or a birth weight of 500 to 999 g who were born in Norway in 1999 and 2000. Results. Of 636 births, 174 infants (27%) were stillborn or died in the delivery room, 86 (14%) died in the NICU, and 376 (59%) were discharged from the hospital. The risk of being registered as stillborn or not being resuscitated increased with decreasing GA below 25 weeks. The survival rates for all births and for infants admitted to a NICU were, respectively, 0% for <23 weeks, 16% and 39% for 23 weeks, 44% and 60% for 24 weeks, 66% and 80% for 25 weeks, 72% and 84% for 26 weeks, 82% and 93% for 27 weeks, and 69% and 90% for >27 weeks. For the survivors, days of mechanical ventilation decreased from a median of 37 days to 3 days and the proportion in need of oxygen at 36 weeks� postconceptional age decreased from 67% to 26% at 23 and 27 weeks� GA, respectively. At 40 weeks� postconceptional age, the respective figures were 11% and 6%. The proportion with retinopathy of prematurity (ROP) requiring treatment decreased from 33% for GA of 23 weeks to 0% for >25 weeks. Periventricular hemorrhage of more than grade 2 occurred for 6% of the survivors and significant periventricular leukomalacia occurred for 5%, with no significant association with GA. The proportion of survivors without severe neurosensory or pulmonary morbidity increased from 44% for 23 weeks� to 86% for 27 weeks� GA. Apart from ROP, the morbidity rate was not associated with GA. Conclusions. The survival rate was high and the morbidity rate at discharge home was low in the present study, compared with previous population-based studies. With the exception of ROP, the morbidity rates among the survivors were not higher at the lowest GAs, possibly because withholding treatment was considered more acceptable for the most immature infants. The need for intensive care increased markedly for survivors with the lowest GAs.

• Klingenberg, Claus; Aarag, Elizabeth; Rønnestad, A; Sollid, johanna u ericson; Abrahamsen, TG & Kjeldsen, Gry [Vis alle 7 forfattere av denne artikkelen] (2005). Coagulase-negative Staphylococcal Sepsis among Neonates: Association between Antibiotic Resistance, Biofilm Formation and the Host Inflammatory Response. The Pediatric Infectious Disease Journal. ISSN 0891-3668. 24, s. 817–822.
• Markestad, Trond; Kaaresen, Per Ivar; Rønnestad, Arild; Reigstad, Hallvard; Lossius, Kristin & Medbø, Sverre [Vis alle 10 forfattere av denne artikkelen] (2005). Early death, morbidity, and need of treatment among extremely premature infants. Pediatrics. ISSN 0031-4005. 115(5), s. 1289–1298.
• Rønnestad, Arild; Abrahamsen, Tore G.; Medbø, Sverre; Reigstad, Harald; Lossius, Kristin & Kaaresen, Per Ivar [Vis alle 10 forfattere av denne artikkelen] (2005). Late-Onset Septicemia in a Norwegian National Cohort of Extremely Premature Infants Receiving Very Early Full Human Milk Feeding. Pediatrics. ISSN 0031-4005. 115, s. e269–e276. doi: 10.1542/peds.2004-1833. Vis sammendrag

  doi:10.1542/peds.2004-1833

• Klingenberg, Claus; Sundsfjord, Arnfinn; Rønnestad, A; Mikalsen, J; Gaustad, P & Flægstad, Trond (2004). Correlation between aminoglycoside resistance phenotype and genotype in blood culture isolates of coagulase negative staphylococci from a single neonatal intensive care unit, 1989-2000. Journal of Antimicrobial Chemotherapy. ISSN 0305-7453. 54(5), s. 889–896.
• Klingenberg, C.; Sundsfjord, A; Rønnestad, Arild Erlend; Mikalsen, J; Gaustad, Peter & Flægstad, Trond (2004). Phenotypic and genotypic aminoglycoside resistance in blood culture isolates of coagulase-negative staphylococci from a single neonatal intensive care unit, 1989�2000. Journal of Antimicrobial Chemotherapy. ISSN 0305-7453. 54(5), s. 889–896. doi: 10.1093/jac/dkh453. Vis sammendrag

  Objectives: To investigate the prevalence of aminoglycoside resistance and genes encoding aminoglycoside-modifying enzymes (AME) in blood culture isolates of coagulase-negative staphylococci (CoNS) from neonates. Materials and methods: A total of 180 isolates from 148 patients collected in a single neonatal unit over a 12 year period were examined for susceptibility to gentamicin, tobramycin, netilmicin, amikacin and arbekacin by Etest and/or disc diffusion. AME genes were detected by PCR. Results: The overall non-susceptibility rates to gentamicin, tobramycin, netilmicin, amikacin and arbekacin were 66%, 68%, 52%, 38% and 1%, respectively. Gentamicin non-susceptibility rates were 4% and 91% in methicillin-susceptible and -resistant isolates, respectively. aac(6')-Ie-aph(2'')-Ia, aph(3')-IIIa and/or ant(4')-Ia were encountered in 125 (69%), 1 (0.5%) and 30 (16.6%) isolates, respectively. Forty-six (26%) isolates negative for AME genes were susceptible to all aminoglycosides. In contrast, 115 (92%), 91 (73%) and 66 (53%) of aac(6')-Ie-aph(2'')-Ia positive isolates were non-susceptible to gentamicin, netilmicin and amikacin, respectively. Only one isolate showed arbekacin resistance. However, aac(6')-Ie-aph(2'')-Ia positive isolates and isolates with gentamicin MIC 128 mg/L displayed a significant reduction in arbekacin inhibition zones. Conclusions: A high prevalence of aminoglycoside resistance was detected and associated with methicillin resistance. Discrepancies between phenotypic and genetic detection of aminoglycoside resistance were discerned. Gentamicin was the preferred substrate for phenotypic detection of aac(6')-Ie-aph(2'')-Ia. Arbekacin showed favourable antibacterial activity even in aac(6')-Ie-aph(2'')-Ia-positive isolates. We suggest including arbekacin in future clinical trials of empirical treatment of late onset neonatal sepsis.

Se alle arbeider i Cristin

• Berisha, Gazmend; Boldingh, Anne Marthe; Blakstad, Elin Wahl; Rønnestad, Arild Erland & Solevåg, Anne Lee (2023). Corrigendum: Management of the unexpected difficult airway in neonatal resuscitation(Front Pediatr., (2021), 9, (699159), 10.3389/fped.2021.699159). Frontiers in pediatrics. ISSN 2296-2360. 10. doi: 10.3389/fped.2022.1124050.
• Ohnstad, Mari Oma; Stensvold, Hans Jørgen; Pripp, Are Hugo; Tvedt, Christine Raaen; Jelsness-Jørgensen, Lars-Petter & Astrup, Henriette [Vis alle 15 forfattere av denne artikkelen] (2022). Extubating extremely premature newborns: predictors of success and reasons for failure.
• Strømmen, Kenneth; Lyche, Jan Ludvig; Moltu, Sissel; Müller, Mette Helen Bjørge; Blakstad, Elin Wahl & Almaas, Astrid Nylander [Vis alle 12 forfattere av denne artikkelen] (2021). Corrigendum to “High urinary concentrations of parabens and bisphenol A in very low birth weight infants”. Chemosphere. ISSN 0045-6535. 275. doi: 10.1016/j.chemosphere.2021.130613.
• Rønnestad, Arild Erlend & Hansen, Thor Willy Ruud (2014). Nevrologiske tilstander hos nyfødte, Nevrologi og nevrokirurgi fra barn til voksen, 6.utgave. Forlaget Vett & Viten AS. ISSN 978-82-412-0709-9. s. 155–172.
• Moltu, Sissel; Blakstad, Elin Wahl; Strømmen, Kenneth; Almaas, Astrid; Nakstad, Britt & Rønnestad, Arild Erlend [Vis alle 11 forfattere av denne artikkelen] (2013). Enhanced nutritional support enables postnatal growth similar to normal in utero growth in very low birth weight infants.
• Blakstad, Elin Wahl; Strømmen, Kenneth; Moltu, Sissel; Wattam-Bell, J; Nordheim, Trond & Almaas, Astrid [Vis alle 14 forfattere av denne artikkelen] (2013). Enhanced feeding improved global motion visual event-related potentials in very low birth weight infants.
• Strømmen, Kenneth; Blakstad, Elin Wahl; Moltu, Sissel; Almaas, Astrid; Amlien, Inge & Rønnestad, Arild Erlend [Vis alle 13 forfattere av denne artikkelen] (2013). Enhanced Nutrition to very low birth weight infants improves nutrition of cerebral connective tracts.
• Tandberg, Bente Silnes; Sandtrø, Hege Pettersen & Rønnestad, Arild Erlend (2012). DO MOTHERS AND FATHER TO PRETERM EVALUATE THEIR EXPERIENCE OF STRESS AND NURSE’S SUPPORT DIFFERENTLY WHEN HOSPITALIZED IN A NICU?
• Lindenskov, Paal Helge H.; Rønnestad, Arild Erlend & Skari, Hans (2012). Et spedbarns mistrivsel endte med døden. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 18(132), s. 1964–1967. doi: 10.4045/tidsskr.11.1026.
• Moltu, Sissel; Blakstad, Elin Wahl; Strømmen, Kenneth; Almaas, Astrid; Nakstad, Britt & Rønnestad, Arild Erlend [Vis alle 11 forfattere av denne artikkelen] (2012). Økt tilførsel av næring-stoffer gir bedret vekst hos svært premature barn.
• Strømmen, Kenneth; Blakstad, Elin Wahl; Moltu, Sissel; Almaas, Astrid; Westerberg, Ane Cecilie & Amlien, Inge [Vis alle 16 forfattere av denne artikkelen] (2012). Enhanced Nutrition to Very Low Birth Weight Infants Improves Maturation of Cerebral Connective Tracts.
• Rønnestad, Arild Erlend; Rootwelt, Terje & Hansen, Thor Willy (2010). Nevrologiske tilstander hos nyfødte. I Gjerstad, Leif; Helseth, Eirik & Rootwelt, Terje (Red.), Nevrologi og nevrokirurgi. Fra barn til voksen. 5.utgave. Forlaget Vett & Viten AS. ISSN 978-82-412-0686-3. s. 159–176.
• Haugen, Guttorm; Rønnestad, Arild Erlend & Kroken, Mette (2009). Variations in fetal phenotype in Prader-Willi syndrome. Prenatal Diagnosis. ISSN 0197-3851. 29(3), s. 294–294. doi: 10.1002/pd.2207.
• Klingenberg, Claus; Rønnestad, Arild Erlend; Anderson, Annaliesa; Abrahamsen, Tore G; Flægstad, Trond & Sollid, J.E. (2006). Persistent strains of coagulase negative staphylococci in a neonatal intensive care unit are characterized by high levels of biofilm production and antibiotic resistance. European Society for Pediatric Infectious Diseases, Meeting Abstract Book. Vis sammendrag

  Background and aims Coagulase-negative staphylococci (CoNS) are the major cause of nosocomial sepsis in the neonatal intensive care unit (NICU). We wanted to investigate whether persistent CoNS strains possess specific bacterial characteristics compared with sporadic strains. Methods During a 12-year period we obtained 180 CoNS blood culture isolates from 150 neonates at one single NICU. All isolates were typed with pulsed field gel electrophoresis (PFGE). We also performed multi locus sequence typing (MLST) on 90 S. epidermidis isolates. Phenotypic antibiotic susceptibility to a broad range of antibiotics was analyzed with Etest. Virulence genes encoding methicillin and aminoglycoside resistance were detected with PCR. In addition, we analyzed phenotypic biofilm production and genetic determinants for biofilm formation. Results There was a high degree of concurrence between PFGE- and MLST- typing. Four S. epidermidis clusters contained 66 (6 - 9 - 15 - 36) isolates, one S. haemolyticus cluster 14 isolates, and one S. hominis cluster 7 isolates. The other 93 isolates were divided among 62 PFGE-types. S. epidermidis cluster strains were isolated from children with lower birth weight compared with non-clusters strains (1420 g versus 2034 g, p = 0.001). Cluster strains were evenly distributed among isolates causing sepsis and isolates considered as contaminants. Antibiotic resistance rates (methicillin, gentamicin, erythromycin, clindamycin and fusidic acid) and biofilm production were significantly higher among cluster strains compared with non-cluster strains. Conclusions CoNS cluster isolates were characterized by high levels of biofilm production and antibiotic resistance, enabling them to survive and persist in the NICU environment. Persistent strains colonized and invaded the smallest infants who were exposed to more invasive procedures and had longer hospital stay.

• Rønnestad, Arild Erlend (2005). Oppdatering om Norsk Nyfødtmedisinsk Nettverk. Vis sammendrag

  Subgruppemøte Neonatologi Pediaterdagene UUS, H2005, Torsdag 13.10 kl 17-19

• Matthews, Iren; Brun, Henrik; Rønnestad, Arild Erlend & Saugstad, Ola Didrik (2005). Mekonium aspirasjon øker NO i ekspirasjonsluft. Paidos: Tidsskrift for Norsk barnelegeforening. ISSN 1503-5360.
• Rønnestad, Arild Erlend (2005). Reddes av morsmelk. [Avis]. Verdens Gang. Vis sammendrag

  En ny studie viser at morsmelk reduserer dødelighet og forekomst av alvorlig infeksjon hos ekstremt tidlig fødte barn. I samarbeid med Medisinsk Fødselsregister har et team av forskere fulgt ekstremt premature barn over en periode på to år. - Det som viste seg å ha aller størst betydning for risikoen for alvorlig infeksjon, var hvor raskt de for tidlig fødte barna var fullt ernært på morsmelk, sier Arild Rønnestad, overlege ved Rikshospitalet. - I en del land er det vanlig praksis å bruke intravenøs ernæring over en lang periode hos premature barn. Dette er den første undersøkelsen vi kjenner til som dokumenterer at man med suksess kan gi ekstremt premature barn morsmelk veldig tidlig, forteller Rønnestad.

• Rønnestad, Arild Erlend (2005). Infeksjoner hos barnet i forbindelse med fødsel og nyfødtperioden.
• Rønnestad, Arild Erlend (2005). Nasjonale diagnosekriterier og Nasjonalt Nyfødtregister vil gi mer lik (likere) koding i nyfødtmedisin.
• Rønnestad, Arild Erlend (2005). Hvordan går det med de minste premature. Resultater fra den norske Ekstrem Prematuritet studien.
• Klingenberg, Claus; Aarag, E.; Rønnestad, Arild Erlend; Sollid, J.E.; Abrahamsen, Tore G & Flægstad, Trond (2005). Biofilm forming coagulase-negative Staphylococci are associated with decreased neonatal inflammatory response in late onset sepsis. Vis sammendrag

  Background: Coagulase-negative staphylococci (CoNS) are the most prevalent pathogens causing late onset sepsis in neonates. They are often multi-resistant to antibiotics and the ability to form biofilm is considered their main virulence determinant. The relationship between antibiotic resistance, biofilm formation and clinical outcome of CoNS infections is largely unknown. Methods: During a 12-year period we identified 150 neonates having 164 suspected septic episodes with growth of CoNS in blood culture. We examined the relationship between antibiotic resistance, phenotypic biofilm production and genetic determinants for biofilm formation in different CoNS species, and their correlation with neonatal inflammatory response. Results: Eighty-five episodes were defined as true sepsis, and 79 episodes of CoNS growth in blood culture were considered contaminations. Significantly higher prevalences of both phenotypic and genotypic β-lactam and aminoglycoside resistance were seen in invasive isolates compared with contaminants. Sixty-one percent of S. epidermidis isolates produced biofilm compared with 26 % of CoNS non-epidermidis (P < 0.001). As expected there was a strong correlation between the presence of icaD and biofilm production. We observed no difference in phenotypic biofilm production or genetic determinants for biofilm formation between invasive isolates and contaminants. C-reactive protein (CRP) levels as a marker of inflammatory response were higher in CoNS sepsis caused by methicillin and aminoglycoside resistant versus susceptible isolates (P = 0.031). In contrast, there was a significant association between a lower CRP response and biofilm positive isolates (P = 0.018). Antibiotic resistance was significantly correlated with biofilm production in S. epidermidis, but not in other CoNS species. Conclusions: Evasion of the host immune system by biofilm formation seems to be a clinically relevant mechanism in CoNS causing neonatal sepsis. The close contact of bacteria within a biofilm may facilitate horizontal exchange of genetic information. This might explain the high level of multidrug-resistance in biofilm positive S. epidermidis. The impact of antibiotic resistance and virulence determinants on clinical outcome of neonatal CoNS sepsis warrants additional clinical studies.

• Klingenberg, Claus; Sundsfjord, Arnfinn; Rønnestad, A; Mikalsen, J; Gausiad, P & Flægstad, Trond (2004). Phenotypic and genotypic aminoglycoside resistance in blood culture isolates of coagulase negative staphylococci from a single neonatal intensive care unit, 1989-2000. Pediatric Research. ISSN 0031-3998. 56, s. 486–486.
• Klingenberg, C.; Sundsfjord, A; Rønnestad, Arild Erlend; Mikalsen, J; Gaustad, Peter & Flægstad, Trond (2004). Phenotypic and genotypic aminoglycoside resistance in blood culture isolates of coagulase-negative staphylococci from a single neonatal intensive care unit, 1989�2000. Pediatric Research. ISSN 0031-3998. 56(3). Vis sammendrag

  ESPR EUROPEAN SOCIETY FOR PEDIATRIC RESEARCH: Stockholm, Sweden September 19-22, 2004

• Brun, Henrik; Matthews, Iren; Rønnestad, Arild Erlend & Saugstad, Ola Didrik (2004). Hypoksi og Mekonium-aspirasjon øker NO i ekspirasjonsluft.
• Rønnestad, Arild Erlend (2004). Sepsis in a Norwegian national cohort of extremely premature infants during 1999 and 2000. A population based prospective study.
• Nordgård, Lise; Flægstad, Trond; Glad, trine; Sundsfjord, A.; Rønnestad, Arild Erlend & Olsvik, Ørjan (1999). Lack of correlation between resistance to Oxacillin and the Presence of the mecA-gene in Clinical Isolates of Staphylococcus epidermidis.
• Rønnestad, Arild Erlend & Abrahamsen, Tore G (2006). Neonatal septicaemia: Epidemiology, diagnostic and therapeutic aspects. Unipub forlag. ISSN 82-8072-833-3.

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