ORCHESTRA is a prospective, single-centre observational cohort study conducted in an academic colorectal surgery unit. Consecutive eligible patients undergoing colorectal or anal procedures performed by one designated surgeon are observed during routine surgical care. The operating surgeon and participating theatre staff gave consent to observation and questionnaire assessment at the start of the study.

Two independent observers record naturally occurring distractions in real time, including their type, operative phase and observable impact. Distractions are classified as A, potentially distracting; B, visibly distracting the team; or C, interrupting operative flow. The principal exposure is the number of C-class events per operation. Additional summaries include category-specific counts, total distraction count and a weighted score calculated as A + 2B + 3C.

Intraoperative adverse events are assessed using ClassIntra, with the maximum grade per operation serving as the primary outcome. Immediately after surgery, the operating surgeon completes the study's SURG-TLX implementation and STAI-State. Team collaboration is assessed by the observers using the study's OTAS implementation. Recorded patient and procedure characteristics include age, ASA physical status, obesity, procedure category and operative duration.

Ordinal regression examines associations with increasing ClassIntra severity. Related models consider workload and anxiety together and separately because these measures may be strongly correlated. Additional analyses describe distraction patterns, teamwork, workload and anxiety, and assess more clinically consequential events using a ClassIntra grade II or higher threshold. The study is observational and does not establish causal effects.