Mechanical large-bowel obstruction is a common and high-risk emergency surgical condition with substantial variation in diagnostic evaluation, operative timing, and management strategies across institutions and healthcare systems. Evidence guiding optimal management remains limited and is largely derived from retrospective or single-center studies. IMPEL is an international, multicenter, time-bound, prospective observational cohort study designed to characterize real-world presentation, diagnostic pathways, operative and non-operative management, and short-term outcomes in adults presenting with mechanical large-bowel obstruction. By capturing standardized patient-level, radiologic, operative, and outcome data across diverse acute care settings, IMPEL aims to describe contemporary practice patterns, quantify variation in care, and identify factors associated with morbidity, mortality, and stoma-related outcomes.
IMPEL is a prospective, non-randomized, observational snapshot audit conducted across international acute care hospitals managing emergency general surgery. Participating centers enroll consecutive adult patients presenting with mechanical large-bowel obstruction during a predefined 90-day inclusion period within a six-month global study window. Patients are managed according to local standard practice; no interventions are assigned by the study protocol. Data collected include baseline characteristics and comorbidity burden, clinical frailty, diagnostic imaging features, operative and non-operative management strategies (including bridge-to-surgery approaches), perioperative outcomes, and short-term follow-up outcomes. Stoma creation, intent, and reversal status are recorded, with follow-up to six months for stoma outcomes. The study is structured in accordance with STROBE guidelines for observational research. Analyses addressing comparative or causal questions will follow target trial emulation principles, including explicit definition of eligibility, time zero, treatment strategies, and estimands, without implying interventional assignment. IMPEL is intended to provide a contemporary international reference standard for the management of large-bowel obstruction, inform future interventional studies, and support quality improvement and guideline development efforts.
Study Type
OBSERVATIONAL
Enrollment
500
30 day morbidity
Occurrence of postoperative complications within 30 days of hospital day zero (baseline) or date of surgery, graded using the Clavien-Dindo classification.
Time frame: From hospital admission date or date of surgery (whichever is later) to 30 days later.
30 day mortality
All-cause mortality occurring within 30 days of date of hospital admission (day zero) for mechanical large-bowel obstruction, irrespective of management strategy.
Time frame: 30 days
Stoma creation
Creation of any intestinal stoma during the index admission for mechanical large-bowel obstruction, including stoma type and intended purpose (defunctioning anastomosis; bridge to definitive resection; non-restorative/palliative; or damage-control).
Time frame: From hospital day 0 (baseline) to 90 days.
Stoma reversal
Number of reversal (closure) of any diverting or end stoma, created during the index admission, within 6 months of hospital discharge, assessed through routine clinical follow-up and medical record review.
Time frame: from hospital discharge (baseline) to 6 months
Length of hospital stay
Duration of the index hospital admission day 0 (baseline) to discharge of the patients from the hospital. The event dischage is defined as the day when the patients quit the hospital of the index admission, for these reasons: he's sent home, he's sent to another hospital, he dies dies. This measure in expressed in days.
Time frame: From hospital day 0 (baseline) to dischagre in a time frame of 90 days.
Association of admitting specialty and on-call model with clinical outcomes and care processes.
Clinical outcomes and care processes, including 30-day major morbidity (Clavien-Dindo grade ≥III), 30-day mortality, time (in hours) from hospital admission(baseline, day zero) to definitive intervention, and stoma creation, will be evaluated in Association to admitting specialty (emergency surgery vs colorectal surgery vs other) and the hospital's out-of-hours emergency general surgery coverage model (dedicated emergency surgery service vs elective subspecialty rota).
Time frame: From index admission (day 0) to 30 days (for 30-day outcomes).
Use of minimally invasive surgical approach
Use of a minimally invasive surgical approach (laparoscopic, robotic, or hybrid), including conversion to open surgery where applicable, during operative management of large-bowel obstruction.
Time frame: Index surgical procedure
Number of participants with self expanding metallic stents.
Use of self expanding metallic stent before surgical resection in patients with colonic obstruction.
Time frame: From hospital day 0 (baseline) up to 90 days
Unplanned readmission
Unplanned hospital readmission related to complications or sequelae of large-bowel obstruction or its management.
Time frame: From initial inpatient hospitalization (baseline) up to 90 days
Patient-reported assessment of gastrointestinal recovery
Patient-Reported Outcomes of Gastrointestinal Recovery (PRO-diGI) will be used to assess appetite, oral intake, bowel function, nausea/vomiting, abdominal pain, fatigue, and overall gastrointestinal wellbeing using ordered categorical items and a 0-100 visual analogue scale (0=worst, 100=best). Where feasible within routine workflows, PRO-diGI will be administered at prespecified time points.
Time frame: From day 0 (baseline) up to 30 days.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.