(ShareCast News) - Deltex Medical Group's stocks plunged Wednesday morning after reporting wider first-half losses.The company, which manufactures and markets oesophageal Doppler monitoring, released their first half results to 30 June 2015.They posted an operating loss of £2.1m, down from £1.5m for H1 last year, due to planned investments in the US to develop sales and operational improvements.It's those same investments that pushed losses before non-cash costs down to £1.7m from £0.6m in the same period last year.Revenue was also down £0.3m to £2.7m.However the company reported that their US probe revenues are up 28% and their platform programme there is on track, with five new clients in the first half of the year.International probe revenues are up 20%, with the strongest growth from larger markets including France.Shares in the company plunged on the back of the news, down 14.29% to 4.5p at 0950 BST.Deltex Medical's chairman Nigel Keen said they're increasing their focus on growing export markets, particularly the US."We are building a strong pipeline of US accounts that we expect to contribute to more rapid growth in sales and we are on track with our plans to build a strong platform for medium term national rollout in the USA."Keen said the shift in their focus is due to the challenging UK market."Traction for our products is growing in other international markets as acceptance of the need for optimal intra-operative fluid management is broadening beyond the UK where, in response to more challenging UK market conditions, we are taking steps to maximise the cash in-flows we generate from our UK sales operation."