Table 2 Essential recommendations for ICG-guided surgery in the emergency setting

Which clinical scenarios and indications for the use of ICG fluorescence guided surgery in the emergency setting to improve outcomes in urgent surgical patients?

ICG Cholangiography in Acute Cholecystitis

ICG cholangiography enhances visualization of biliary structures during cholecystectomy, reducing operative time, conversion rates, and negative outcomes. [QoE C]

The WSES Panel of Experts recommends ICG cholangiography for accurate real-time visualization of the extra-hepatic biliary tree in laparoscopic cholecystectomies for severe cholecystitis, particularly in selected patients when skills and equipment are available. [Strong recommendation based on low level evidence 1C]

In obese patients or in case of severe inflammatory cholecystitis, visibility of extra-hepatic biliary structures may be reduced due to tissue thickness, potentially complicating the use of ICG cholangiography

ICG Angiography in Intestinal Ischemia and Strangulated Bowel

ICG angiography safely evaluates intestinal perfusion patterns in acute intestinal ischemia and strangulated bowel, with adequate visualization reported in most cases. [QoE C]

The WSES Panel of Experts recommends ICG angiography to guide intraoperative decision-making in patients with mesenteric ischemia and strangulated bowel to assess blood flow and bowel viability, when it is available and feasible. [Strong recommendation based on low level evidence 1C]

Consideration should be given to the patient's hemodynamic status, as impaired perfusion may affect the effectiveness of ICG imaging

ICG in Abdominal Trauma

In the trauma setting, ICG aids in assessing bowel viability in mesenteric lacerations and hematomas, helping surgeons decide whether to resect or preserve bowel. [QoE C]

The WSES Panel of Experts suggests considering ICG angiography in the trauma setting to assess blood perfusion in high-risk intestinal segments, guiding repair decisions in hemodynamically stable patients. [Moderate recommendation based on low level evidence 2C]

The presence of significant hemorrhage or trauma may complicate the interpretation of ICG fluorescence imaging

ICG for Anastomotic Leak Prevention

ICG fluorescence angiography may assist in preventing anastomotic leakage by assessing vascular perfusion of intestinal anastomoses. [QoE C]

The WSES Panel of Experts recommends using ICG fluorescence angiography to evaluate perfusion at the intestinal anastomosis site to prevent leaks after emergency resection, when available. [Strong recommendation based on low level evidence 1C]

The efficacy of ICG angiography may be reduced in cases with edema or thick tissue, which can obscure visual assessment of perfusion at the anastomotic site

Which patients’ factors and clinical features do influence the quality of ICG fluorescence imaging in the emergency setting?

In which patients and settings, should the ICG-guided emergency surgery be contraindicated?

ICG is generally safe, but contraindicated in patients with allergies to iodine-based contrast media. Its use in pregnant patients is not absolutely contraindicated, and inotropes do not seem to affect ICG imaging. [QoE C]

The WSES Panel of Experts recommends evaluating the use of ICG fluorescence imaging case-by-case in high-risk procedures, weighing the low risk of adverse reactions against potential negative outcomes. [Strong recommendation based on low level evidence 1C]

The WSES Panel of Experts suggests that the hemodynamic status should be the main clinical factor to consider when deciding to perform an intestinal resection and anastomosis in case of acute intestinal ischemia and strangulated hernias. In any condition in which the tissues are very thick due to edema and obesity, the fluorescence intensity can be reduced. However, the ICG angiography and cholangiography are valid tools to support the surgeon’s decision in the emergency setting and should be used if they are available [Moderate recommendation based on a low and very low level evidence 2C]

Patients with known allergies to iodinated contrast agents should not receive ICG, and its safety in pregnant patients should be carefully considered

In any condition in which the tissues are very thick due to edema and obesity, the fluorescence intensity can be reduced

Which protocol of administration, image acquisition and interpretation should be used in different urgent clinical scenarios including cholecystitis, incarcerated/stragulated hernia, intestinal ischemia, and intestinal and bowel anastomosis evaluation?

For fluorescence cholangiography, ICG should be administered intravenously at the induction of anesthesia, with a recommended dose of 5 mg. The timing of image acquisition should be prior to dissection for optimal assessment. [QoE C]

For fluorescence angiography, ICG should be administered intravenously, typically as a bolus of 5 mg. The timing of administration is crucial, with injection occurring just prior to imaging acquisition (1–2 min before) for optimal assessment [QoE C]

The WSES Panel of Experts recommends timely intravenous administration of ICG for optimal imaging, with proper dosing and dilution protocols to ensure effectiveness during various surgical scenarios. [Strong recommendation based on low level evidence 1C]

Protocols for administration may vary, and factors such as patient weight and clinical condition must be taken into account when determining the appropriate dose and timing of ICG administration

What are the advantages and disadvantages, including absolute/relative contraindications, limitations and cost/effectiveness of ICG implementation in emergency and trauma surgery?

ICG imaging has minimal limitations in assessing bowel perfusion, but quality may vary based on the surgical team's experience. [QoE C-D]

The WSES Panel of Experts recommends implementation of ICG in emergency surgeries for assessing intestinal and anastomotic viability and aiding difficult dissections for acute cholecystitis, emphasizing that it has significant effectiveness at minimal cost when properly utilized. [Strong recommendation based on low and very low level evidence 1C]

The subjective quality of ICG imaging relies heavily on the surgeon's experience, which may lead to variability in interpretation and effectiveness

Indocyanine green fluorescence dye is water soluble, FDA approved, and safe for human use. The only known absolute contraindication is in patients with a documented allergy to iodides or iodinated imaging agents. [QoE B-C]

The WSES Panel of Experts recommends against the administration of ICG dye in patients with known allergies to iodides and iodinated imaging agents. [Strong recommendation based on moderate and low level evidence 1B-C]

Additional considerations regarding patient history and specific allergies should be assessed before administration to mitigate the risk of adverse reactions