Flight Crew Air Transport Pilot (ATP)
Workload; Confusion; Distraction; Situational Awareness; Time Pressure; Communication Breakdown
Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Took Evasive Action; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Became Reoriented
Human Factors; Procedure; Aircraft; Chart Or Publication; Environment - Non Weather Related
We received a change of runway and ATIS change during pushback following engine start of number 2 engine.  Single engine taxi was planned and information was briefed and changed in the performance computer and the CDU after engine start; but before the Before Taxi checklist was called. After making all the changes to the performance computer and CDU reviews were made; numbers and flap settings were still the same.  I missed calling for the checklist and when as we switched from Ramp Control to Ground Control for taxi instructions; we immediately saw that the flaps were not set for takeoff.
A B737-700 crew became distracted during pushback by a runway and ATIS change. During single engine taxi they realized the performance computer and FMC distractions caused them to miss lowering the flaps.