** Medical device maker Becton Dickinson's BDX.N shares fall 2.7% to $181.78 during market open

** Co's CFO Chris DelOrefice to leave on December 5 to pursue new opportunity; search for permanent successor underway

** Co names Vitor Roque, senior VP of finance, interim CFO

** BDX says vaccine-related devices and academic research demand were weaker than expected

** Co reports preliminary Q4 revenue of $5.9 billion vs analysts' estimate of $5.91 billion - data compiled by LSEG

** RBC analysts say preliminary results came in slightly below the low end of the company's outlook

** Brokerage J.P.Morgan says challenges in Pharma Systems and Biosciences have continued to be less transient than hoped for

** Including session moves, stock down ~18% YTD

(Reporting by Sahil Pandey in Bengaluru)

((Sahil.pandey@thomsonreuters.com))