U.S. stock futures lower, Nasdaq 100 down 2%. Intuitive Surgical shares dip 11.3% after Q2 earnings beat estimates. Other stocks also falling in pre-market.

Intuitive Surgical shares slid to a fresh 52-week low Tuesday, caught in a broader pullback across medical device names and pressured by a string of Wall Street price-target cuts.

Intuitive Surgical tumbled Tuesday after HCA Healthcare trimmed its full-year earnings outlook, noting a drop in surgeries.