This study is a prospective randomized controlled trial evaluating the use of a fluorescent dye, indocyanine green (ICG), in the identification of important bile duct anatomy during emergent same-admission cholecystectomy. Participants will be randomized into either the control arm, which uses the standard of care white light during laparoscopy or the intervention arm, which will use ICG fluorescent cholangiography as an adjunct to white light to visualize the biliary anatomy. The investigators hypothesize that the use of fluorescent cholangiography will increase the rates of identification of important biliary anatomy during laparoscopic cholecystectomy. The effectiveness, feasibility, and safety will be compared between the two groups using a post-operative survey form the surgeons will complete prior to exiting the operating room.

Near-infrared fluorescent imaging techniques have shown promise in aiding to delineate and visualize extrahepatic biliary structures. Indocyanine green (ICG) is a water-soluble fluorescent dye that has been shown to improve visualization of biliary anatomy under fluorescent cholangiography. The standard of care for many acute biliary disease conditions, such as acute cholecystitis, remains early laparoscopic cholecystectomy. Even though real-time fluorescent cholangiography using ICG has the potential to enhance the visualization of biliary structures and anatomy, and therefore reduce the risk for bile duct injury, the majority of the studies published to date exclude acute biliary disease patients. The pathophysiology of acute biliary disease processes is associated with inflammation and adhesions that increase the challenge of achieving a critical view of safety. The investigators propose that using ICG and fluorescent cholangiography near-infrared imaging techniques as an adjunct in acute care laparoscopic cholecystectomies has the potential to help mitigate the increased risk of bile duct injury by increasing extrahepatic biliary structure detection and surgeon confidence.

Eligible patients will be identified through their initial clinical evaluation, which will be verified by the patient's primary surgeon. If and once a patient has been confirmed as eligible, the surgeon or designate will introduce the clinical trial design in detail. If after being introduced to the study and having had the opportunity to ask questions, the patient is willing to participate, the patient will be asked to review and sign the informed consent document.

Upon entry into the clinical trial, the allocation sequence will be generated using a block randomization schema with computer-generated random numbers in a 1:1 ratio, with block sizes of 4 by a co-investigator with no clinical involvement in the trial. The same co-investigator will prepare sequentially numbered, opaque, sealed and stapled envelopes and stored them in a locked cabinet in the operating room control desk. Each envelope contained instructions for the arm the participant had been randomly assigned to, either treatment (ICG cholangiography) or control (standard white light only) arms. After the research team member has obtained the participant's consent, the surgeon or designates will obtain the next consecutively numbered envelope and proceed to open it after the patient is anesthetized and prior to beginning the surgery.

The patient will be blinded to the result of the randomization until after surgery as the envelope will be opened only after the patient has received their general anesthetic. No blinding of the surgical team, research team members or outcomes assessors will be used in this study given the procedural nature and acute condition of the patients included.

Inclusion Criteria:

• Admission or consultation by the Acute Care Surgery (ACS) service
• Diagnosis of acute biliary disease requiring index laparoscopic cholecystectomy
• Diagnoses of acute cholangitis, choledocholithiasis, and gall stone pancreatitis may be included. However, they must have cleared ducts confirmed via endoscopic ultrasound, ultrasound, ERCP, and/or laboratory investigations.
• Ability to understand and follow study procedures and protocols, and provide signed informed consent.

Exclusion Criteria:

• Female patients who are pregnant or currently breastfeeding
• Known pre-existing liver disease, including cirrhosis
• Known allergy to iodine or shellfish
• Known allergy to indocyanine green (ICG)

Due to the procedural nature of the intervention, we have chosen to run this trial single-blinding, with only the participant being masked to the intervention.