An observational study in Colorectal Diseases and Anal Diseases, sponsored by National and Kapodistrian University of Athens. Recruiting at 1 site in Greece. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-21.
Sponsored by National and Kapodistrian University of Athens · Observational
During surgery, telephone calls, conversations, equipment problems and other events may distract the operating team. Some events interrupt the progress of the operation. The surgeon's workload and anxiety, together with how well the team works together, may also be related to events that occur during surgery.
ORCHESTRA is an observational study of patients undergoing colorectal or anal surgery in a single hospital. Trained observers record distractions during routine operations. After each operation, the surgeon reports workload and anxiety, and an observer assesses teamwork. Intraoperative adverse events are graded using a standard severity classification. The study examines how these measurements are related. It does not assign treatments, introduce distractions or change routine surgical care.
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.
81 studies on the registry are indexed under Intraoperative Complications; 18 are open to participants now.
This study's planned enrollment of 400 is above the median of 167 across 36 observational studies indexed under Intraoperative Complications.
Browse Intraoperative Complications studies →National and Kapodistrian University of Athens is the lead sponsor of 172 studies on the registry; 52 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Consecutive eligible adult patients undergoing colorectal or anal surgery in the participating unit, performed by the designated surgeon during the study period.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
- None.
Consecutive eligible patients undergoing colorectal or anal surgery performed by the designated surgeon in the participating unit. Naturally occurring distractions, surgeon workload and anxiety, team collaboration and intraoperative adverse events are assessed during the index operation.
Other: Naturally occurring operating-room distractions and human factors
Observational recording of naturally occurring distractions and assessment of surgeon workload, situational anxiety and team collaboration during routine surgical care. No experimental exposure is assigned and no change to treatment is prescribed.
Intraoperative adverse-event severity assessed by ClassIntra
The highest ClassIntra grade recorded during the index operation. Grade 0 indicates no intraoperative adverse event; grades I through V indicate increasing severity, with grade V indicating intraoperative death. The case-level ordinal score is analysed in relation to distraction burden and other recorded patient, procedural and human-factor measurements.
Time frame: During the index operation, from anaesthetic induction to extubation
ClassIntra grade II or higher intraoperative adverse event
Occurrence (yes or no) of at least one intraoperative adverse event of ClassIntra grade II or higher, representing a more clinically consequential event. Reported as the number and proportion of operations with such an event.
Time frame: During the index operation, from anaesthetic induction to extubation
Surgeon state-anxiety score
STAI-State total score based on 20 items, with reverse scoring of positively worded items according to the authorised scoring key. The surgeon reports feelings during the surgical case just completed. Scores range from 20 to 80; higher scores indicate greater situational anxiety. Only complete questionnaires are scored.
Time frame: Immediately after completion of the index operation
Surgeon task-load score
Study implementation of SURG-TLX using six domains rated from 1 to 5: mental demand, physical demand, temporal demand, task complexity, situational stress and distractions. The overall score is the unweighted mean of the six ratings, ranging from 1 to 5. Higher scores indicate greater workload.
Time frame: Immediately after completion of the index operation
Observer-rated team collaboration score
Overall teamwork score from the study's OTAS implementation, rated by the observers on a scale from 0 to 6. A score of 0 indicates severely hindered behaviour and 6 indicates highly effective behaviour. Higher scores indicate better team collaboration.
Time frame: Immediately after completion of the index operation
C-class distraction count
Number of C-class events per operation, recorded in real time. C-class events are distractions that interrupt operative flow. This is the principal exposure for the primary analysis. A higher count indicates greater observed interruption burden. The minimum is 0 and there is no fixed upper limit.
Time frame: During the index operation, from anaesthetic induction to extubation
Total and category-specific distraction counts
Number of A-class (potentially distracting), B-class (visibly distracting the team) and C-class (interrupting operative flow) events per operation, and their total, recorded in real time by the observers. The minimum is 0 and there is no fixed upper limit; higher counts indicate greater distraction burden.
Time frame: During the index operation, from anaesthetic induction to extubation
Weighted distraction index
Study-defined score calculated as the number of A-class events plus twice the number of B-class events plus three times the number of C-class events. The minimum is 0, there is no fixed maximum, and higher values indicate greater weighted distraction burden.
Time frame: During the index operation, from anaesthetic induction to extubation
Plan to share: Undecided
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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