LEWISTON — Central Maine Healthcare’s board of directors is backing CEO Jeff Brickman even though he received no confidence votes from medical staff at all three of its hospitals. However, the board also said it is making changes to increase physician input. The board voted Tuesday night to affirm its support for Brickman and his plans for the hospital system, Chairwoman Deborah Dunlap Avasthi said in a memo she sent to employees on Wednesday. “The board’s action is guided by our fiduciary responsibility to CMH and its mission, meaning that it is our responsibility as board members to act in the best long-term interests of CMH, including ensuring that it remains financially viable,” Avasthi wrote. She said the board also agreed to add more doctors to the board and to allow seats for the chiefs of staff of Bridgton Hospital, Rumford Hospital and Central Maine Medical Center in Lewiston.