Superior vena cava flow: feasibility and reliability of the off-line analyses
- 1Department of Paediatrics, Oslo University Hospital, Oslo, Norway
- 2Department of Informatics, University of Oslo, Oslo, Norway
- 3Department of Paediatrics, Vestfold Hospital Trust, Tønsberg, Norway
- 4Faculty of Medicine, University of Oslo, Oslo, Norway
- Correspondence to Anja Lee, Department of Paediatrics, Oslo University Hospital, Ullevål, NO-0407 Oslo, Norway;
- Accepted 8 November 2009
- Published Online First 8 December 2009
Background Superior vena cava (SVC) flow has become a surrogate measure of systemic blood flow in neonates.
Objective The aim of this study was to establish normal SVC flow values in healthy term infants the first 3 days of life and to evaluate the feasibility and reliability of the off-line analyses.
Design Doppler echocardiography of SVC flow was performed in 48 healthy term infants the first 3 days of life. Off-line analyses were thereafter performed by one cardiologist to investigate the changes in SVC flow from day 1 to day 3 and to establish normal values. Intra- and inter-observer variability was analysed in a subset of 20 infants by three paediatric cardiologists.
Results The authors found a decrease in mean SVC flow from 99 ml/kg/min at day 1 to 77 ml/kg/min at day 3. Reliable diameter images were obtained in 85% and velocity recordings in 81%. The mean variability of SVC flow was 17% in the intra-observer analysis and 29% in the inter-observer analysis.
Conclusion The main challenge of the method is the measurement of SVC diameter. The same observer should ideally perform sequential analyses. Special caution should be taken when making clinical implications from non-optimal pictures.
Funding Funding was received from the Department of Research at Oslo University Hospital, Ulleval, and the Unexpected Child Death Society of Norway.
Competing interests None.
Ethics approval This study was conducted with the approval of the regional Committee for Medical Research Ethics and the Scientific Committee at Oslo University Hospital, Ulleval, Oslo, Norway.
Provenance and peer review Not commissioned; externally peer reviewed.
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