There has been a spate of profit warnings among recruitment firms recently but Hydrogen bucked the trend, saying profit before tax for 2011 will come in at the top end of analysts' forecasts.The group has delivered a 9% increase in Net Fee Income (NFI)compared to 2010, with the year-end figure likely to be around £30m.Two relatively new units, pharmaceuticals (+140%) and oil and gas (+60%), now contribute 29% of group NFI.Contract placements accounted for 55% of group NFI during 2011, up from 46% in the previous year, with the rise in the use of contractors demonstrating the caution in the financial services sector towards taking on permanent staff.Ian Temple, Hydrogen's Executive Chairman, said: "We enter 2012 conscious of the current macroeconomic uncertainties, particularly with regard to weakness in the UK economy and the Financial Services sector. However, we will maintain our strategy of selective investment and cost control, and are well placed to take advantage of any growth opportunities as they arise."Over the last 12 months Hydrogen shares have lost 39% of their value and were at a 52-week low before the upgrade to profits guidance. BS