ICU Medical Inc. reached an agreement with Smiths Group plc to buy Smiths Medical division for $2.35 billion in cash and stock. The deal represents an improvement in the terms reached between Trulli Bidco Ltd. and Smiths Group in early August for the purchase of the same division. Trulli, a wholly owned subsidiary of Boston-based equity firm TA Associates, offered $2.3 billion with a kicker of $200 million contingent on future performance. “This is a positive for Smiths, and comes as something of a surprise (to us, and we suspect, investors),” said Andy Douglas, equity analyst, at Jefferies Equity Research. “The uplift in value of $0.4 million is helpful, and the opportunity to share more future upside is also a positive.”