This article evaluates whether providing extra clinical resource during the winter of 2014/15 improved the availability of paediatric intensive care retrieval teams in a North London retrieval service. We explored the potential impact of different staffing patterns in future years to inform service planning. We used retrospective routine data to compare the proportion of referrals refused due to lack of capacity between the winter of 2014/15 and the previous five winters. In the winter of 2014/15, an additional team were on shift for 12% of the time. We compared shifts where the additional team were available in the winter of 2014/15 to similar shifts in previous years. We used mathematical modelling to predict the potential impact of staffing levels in future winters. From 1 November 2014 to 3 January 2015, the service performed 380 emergency retrievals and refused 25 due to no available team (6.2%). The proportion of refusals during shifts with the additional team available in 2014/15 was 4.2% vs 12.4% in similar shifts from 2009/10 to 2013/14 (p = 0.026). Mathematical modelling showed that staffing an additional full-time team could result in 2% of referrals refused compared to 8% without and that much benefit could be obtained by a third team working a 12-hour shift from 10am until 10pm (refusal rate 2.8%).