SnapChole: An International, Time-Bound Prospective Platform Study of Management Strategies and Outcomes in Acute Calculous Cholecystitis

Overview

This study aims to understand how different treatment approaches for acute gallbladder inflammation (acute calculous cholecystitis) affect patient outcomes in real-world hospital settings. Acute calculous cholecystitis is a common condition that occurs when gallstones block the gallbladder and cause infection or inflammation. In more severe cases, patients may develop organ dysfunction, and doctors must decide quickly how best to treat the condition. Treatment options include early surgery to remove the gallbladder, placement of a drainage tube, or treatment with antibiotics alone. The best approach is not always clear, especially for patients who are older, have other medical conditions, or are very unwell. This study will collect information from hospitals around the world about how patients with severe gallbladder inflammation are treated as part of their usual care. No treatments are assigned by the study. All decisions are made by the patient's clinical team. The goal is to compare outcomes between different treatment approaches in patients who could reasonably receive more than one option. The study will examine recovery, survival, need for additional procedures, and time spent in the hospital over 90 days. The findings are intended to help doctors and patients better understand which treatment strategies may lead to better outcomes in different clinical situations, and to improve decision-making in emergency surgical care.

Detailed description

SnapChole is an international, multicenter, prospective, time-bound observational platform study designed to evaluate management strategies and outcomes in adults with acute calculous cholecystitis. The study focuses on patients with severe disease, defined by the presence of organ dysfunction, in whom treatment decisions are influenced by both patient-level factors and system-level capability.

The study is conducted as a prospective clinical audit using routinely collected data and does not alter patient care. Participating centers enroll consecutive eligible patients during a predefined local accrual window. Data are recorded contemporaneously using standardized case report forms and transferred in deidentified form to a central coordinating database. Follow-up extends to 90 days from the index presentation.

The study architecture separates descriptive benchmarking from causal analysis. The full cohort provides a denominator population for characterization of treatment patterns, timing of interventions, and outcomes across centers and healthcare systems. Within this cohort, prespecified analytic subsets are defined at the point of clinical decision-making (time zero), corresponding to the moment at which the treating team determines that one or more management strategies are feasible.

Comparative analyses are structured to align eligibility, treatment assignment, and follow-up, consistent with a target trial emulation framework applied to observational data. Treatment strategies of interest include early cholecystectomy, gallbladder drainage as an initial approach, and antimicrobial-only management. Analyses are restricted to patients in whom the relevant strategies are simultaneously available, in order to reduce bias arising from differences in clinical eligibility or institutional capability.

Exposure is defined as completion of the assigned management strategy within a prespecified interval following the decision point, reflecting real-world delivery of care. Outcomes include days alive and out of hospital at 90 days, mortality, need for additional interventions, and time to achieved source control.

The study also incorporates complementary analyses, including benchmarking of care pathways, evaluation of patient-centered outcomes, and assessment of factors influencing clinical decision-making. Together, these components are intended to provide a comprehensive understanding of how management strategies are selected and how they relate to outcomes in severe acute calculous cholecystitis.

Primary outcome measures

• Days alive and out of hospital at 90 days [Time frame: 90 days from time zero (attending surgeon-level decision point)]

Secondary outcome measures (5)

• All-cause mortality [Time frame: 90 days from time zero]
• Failure of Source Control [Time frame: Within 90 days from time zero]
• Unplanned biliary reintervention [Time frame: within 90 days of time zero]
• Length of hospital stay [Time frame: From hospital admission to hospital discharge, assessed up to 90 days from time zero]
• Time to achieved source control [Time frame: From time zero to completion of source-control intervention, assessed up to 90 days]

Eligibility criteria

Inclusion criteria

• Age ≥18 years
• Presentation with suspected acute calculous cholecystitis
• Diagnosis confirmed prospectively according to Tokyo Guidelines 2018 (TG18) diagnostic criteria
• Classified as severe (TG18 Grade III) disease based on the presence of organ dysfunction
• Managed at a participating center during the study accrual period

Exclusion criteria

• Acalculous cholecystitis
• Isolated choledocholithiasis or acute cholangitis without cholecystitis
• Primary gallstone pancreatitis without concomitant acute cholecystitis
• Elective admission for chronic biliary symptoms
• Prior cholecystectomy

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model

Cohort

Study locations

United States · 1 center

• Hospital of the University of Pennsylvania — Philadelphia

Publications

• Bass GA, Kaplan LJ, Ryan EJ, Cao Y, Lane-Fall M, Duffy CC, Vail EA, Mohseni S. The snapshot audit methodology: design, implementation and analysis of prospective observational cohort studies in surgery. Eur J Trauma Emerg Surg. 2023 Feb;49(1):5-15. doi: 10.1007/s00068-022-02045-3. Epub 2022 Jul 15. PMID 35840703
• Loozen CS, van Santvoort HC, van Duijvendijk P, Besselink MG, Gouma DJ, Nieuwenhuijzen GA, Kelder JC, Donkervoort SC, van Geloven AA, Kruyt PM, Roos D, Kortram K, Kornmann VN, Pronk A, van der Peet DL, Crolla RM, van Ramshorst B, Bollen TL, Boerma D. Laparoscopic cholecystectomy versus percutaneous catheter drainage for acute cholecystitis in high risk patients (CHOCOLATE): multicentre randomised PMID 30297544
• Hernan MA, Robins JM. Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available. Am J Epidemiol. 2016 Apr 15;183(8):758-64. doi: 10.1093/aje/kwv254. Epub 2016 Mar 18. PMID 26994063
• Pisano M, Allievi N, Gurusamy K, Borzellino G, Cimbanassi S, Boerna D, Coccolini F, Tufo A, Di Martino M, Leung J, Sartelli M, Ceresoli M, Maier RV, Poiasina E, De Angelis N, Magnone S, Fugazzola P, Paolillo C, Coimbra R, Di Saverio S, De Simone B, Weber DG, Sakakushev BE, Lucianetti A, Kirkpatrick AW, Fraga GP, Wani I, Biffl WL, Chiara O, Abu-Zidan F, Moore EE, Leppaniemi A, Kluger Y, Catena F, A PMID 33153472
• Okamoto K, Suzuki K, Takada T, Strasberg SM, Asbun HJ, Endo I, Iwashita Y, Hibi T, Pitt HA, Umezawa A, Asai K, Han HS, Hwang TL, Mori Y, Yoon YS, Huang WS, Belli G, Dervenis C, Yokoe M, Kiriyama S, Itoi T, Jagannath P, Garden OJ, Miura F, Nakamura M, Horiguchi A, Wakabayashi G, Cherqui D, de Santibanes E, Shikata S, Noguchi Y, Ukai T, Higuchi R, Wada K, Honda G, Supe AN, Yoshida M, Mayumi T, Gouma PMID 29045062
• Yokoe M, Hata J, Takada T, Strasberg SM, Asbun HJ, Wakabayashi G, Kozaka K, Endo I, Deziel DJ, Miura F, Okamoto K, Hwang TL, Huang WS, Ker CG, Chen MF, Han HS, Yoon YS, Choi IS, Yoon DS, Noguchi Y, Shikata S, Ukai T, Higuchi R, Gabata T, Mori Y, Iwashita Y, Hibi T, Jagannath P, Jonas E, Liau KH, Dervenis C, Gouma DJ, Cherqui D, Belli G, Garden OJ, Gimenez ME, de Santibanes E, Suzuki K, Umezawa A, PMID 29032636

Identifiers

NCT: NCT07568080 · SnapChole

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗