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May 13 (Reuters) - Shares of GMR Solutions GMRS.N fell 10% in their New York Stock Exchange debut on Wednesday, valuing the KKR-backed emergency medical services provider at $3 billion.

The Lewisville, Texas-based company's stock opened at $13.50 apiece, compared with the $15 offer price. It sold about 31.9 million shares in its IPO to raise $478.7 million.

The debut comes after GMR, better known as Global Medical Response, slashed the deal size on Tuesday and sold shares well below its initial marketed range of $22 to $25 apiece, as investors remain cautious toward new listings.

Analysts say the recent IPO pickup remains somewhat precarious, with investors still disciplined on valuations and happy to pass over less-exciting stories.