Background: For preterm infants an association between patient volume and mortality has been described.
Methods: Outcome variables were evaluated for 28 hospitals in Baden-Württemberg for the years 2004-2008. Hospitals with high patient volume were compared to hospitals with a lower patient volume.
Results: Outcomes for 1 164 infants in 2008 and for 4 775 infants in 2004-2008 were analysed. In 2008, mortality of preterm infants less than 32 weeks gestational age (GA) was 9.2% (n=402) in the 5 major hospitals compared to 6.5% (n=520) in the other hospitals (combined mortality 7.7%, n. s., chi-square test). In the years 2004-2008, mortality showed a greater variation in hospitals with a patient volume below 50 and mean mortality was 21.1% higher for infants less than 500 g BW. Hospitals with a patient volume >or= 50 had a lower mortality for infants with BW below 500 g and between 500 g and 749 g (18% and 11%, chi-square test: p<0.05 and <0.01, respectively). For preterm infants with GA below 24 weeks and between 24 and 25 weeks, patient volume and mortality were negatively correlated (p<0.01 and <0.0001, respectively). For infants with a BW >or= 750 g or a GA >or= 26 weeks patient volume had no effect on outcome.
Conclusion: Regionalisation of preterm infants with BW less than 750 g and a GA less than 26 weeks may contribute to reduce mortality. Infants with BW >or= 750 g and a GA >or= 26 weeks may not benefit from indirect quality indicators such as patient volume.