PILLAR of Surgical Decision-Making? Perhaps Not Without More Evidence

Indocyanine green fluorescence angiography in colorectal surgery: A retrospective case-control analysis in Mexico

INTRODUCTION AND AIMS

An anastomotic leak is one of the most dreaded complications in colorectal surgery because it increases postoperative morbidity and mortality. The aim of the present study was to identify whether indocyanine green fluorescence angiography (ICGFA) reduced the anastomotic dehiscence rate in colorectal surgery.

MATERIAL AND METHODS

A retrospective study on patients that underwent colorectal surgery with colonic resection or low anterior resection and primary anastomosis, within the time frame of January 2019 and September 2021, was conducted. The patients were divided into the case group, in which ICGFA was performed for the intraoperative evaluation of blood perfusion at the anastomosis site, and the control group, in which ICGFA was not utilized.

RESULTS

A total of 168 medical records were reviewed, resulting in 83 cases and 85 controls. Inadequate perfusion that required changing the surgical site of the anastomosis was identified in 4.8% of the case group (n = 4). A trend toward reducing the leak rate with ICGFA was identified (6% [n = 5] in the cases vs 7.1% in the controls [n = 6] [p = 0.999]). The patients that underwent anastomosis site change due to inadequate perfusion had a 0% leak rate.

CONCLUSIONS

ICGFA as a method to evaluate intraoperative blood perfusion showed a trend toward reducing the incidence of anastomotic leak in colorectal surgery.

Indocyanine green fluorescence angiography could reduce the risk of anastomotic leakage in rectal cancer surgery: a systematic review and meta-analysis of randomized controlled trials

AIM

Several papers have shown that use of indocyanine green (ICG) decreases incidence of anastomotic leakage (AL) during colonic surgery, but no clear evidence has been found for rectal cancer surgery. Therefore, with this systematic review and meta-analysis of randomized controlled trials (RCTs) we aimed to assess if ICG could also reduce risk of AL in rectal cancer surgery.

METHOD

PubMed, Scopus, CINAHL and Cochrane databases were searched for RCTs assessing the effect of intraoperative ICG on the incidence of AL of the colorectal anastomosis. Pooled relative risk (RR) and pooled risk difference (RD) were obtained using models with random effects. Risk of bias was evaluated with the Rob2 tool and the quality of evidence was assessed using the GRADE Pro tool.

RESULTS

Four RCTs were included for analysis, with a total of 1510 patients (743 controls and 767 ICG patients). The rate of AL was 9% in the ICG group (69/767) and 13.9% (103/743) in the control group (p = 0.003, RR -0.5, 95% CI -0.827 to -0.172, heterogeneity test 0%, p = 0.460). The RD in terms of incidence of AL was significantly decreased by 4.51% (p = 0.031, 95% CI -0.086 to -0.004, heterogeneity test 28%, p = 0.182) when using ICG.

CONCLUSION

Our meta-analysis suggested that use of ICG during rectal cancer surgery could reduce the rate of AL.

Indocyanine green fluorescence imaging during laparoscopic rectal cancer surgery could reduce the incidence of anastomotic leakage: a single institutional retrospective cohort study

BACKGROUND

There is insufficient evidence on whether indocyanine green (ICG) fluorescence angiography can reduce the incidence of anastomotic leakage (AL). This retrospective cohort study aimed to evaluate the effect of ICG fluorescence angiography on AL rates in laparoscopic rectal cancer surgery at a single institution.

METHODS

Patients who underwent laparoscopic low anterior resection or intersphincteric resection with ICG fluorescence angiography (ICG group; n = 73) and patients who underwent a similar surgical procedure for rectal cancer without ICG fluorescence (non-ICG group; n = 114) were enrolled consecutively in this study. ICG fluorescence angiography was performed prior to transection of the proximal colon, and anastomosis was performed with sufficient perfusion using ICG fluorescence imaging. AL incidence was compared between both groups, and the risk factors for AL were analyzed.

RESULTS

AL occurred in 3 (4.1%) and 14 (12.3%) patients in the ICG and non-ICG groups, respectively. In the ICG group, the median perfusion time from ICG injection was 34 s, and 5 patients (6.8%) required revision of the proximal transection line. None of the patients requiring revision of the proximal transection line developed AL. In univariate analysis, longer operating time (odds ratio: 2.758; 95% confidence interval: 1.023-7.624) and no implementation of ICG fluorescence angiography (odds ratio: 3.266; 95% confidence interval: 1.038-11.793) were significant factors associated with AL incidence, although the creation of a diverting stoma or insertion of a transanal tube was insignificant.

CONCLUSION

ICG fluorescence angiography was associated with a significant reduction in AL during laparoscopic rectal cancer surgery. Changes in the surgical plan due to ICG fluorescence visibility may help improve the short-term outcomes of patients with rectal cancer.

Evaluation of inter-user variability in indocyanine green fluorescence angiography to assess gastric conduit perfusion in esophageal cancer surgery

Indocyanine Green Fluorescence Angiography (ICGFA) has been deployed to tackle malperfusion-related anastomotic complications. This study assesses variations in operator interpretation of pre-anastomotic ICGFA inflow in the gastric conduit. Utilizing an innovative online interactive multimedia platform (Mindstamp), esophageal surgeons completed a baseline opinion-practice questionnaire and proceeded to interpret, and then digitally assign, a distal transection point on 8 ICGFA videos of esophageal resections (6 Ivor Lewis, 2 McKeown). Annotations regarding gastric conduit transection by ICGFA were compared between expert users versus non-expert participants using ImageJ to delineate longitudinal distances with Shapiro Wilk and t-tests to ascertain significance. Expert versus non-expert correlation was assessed via Intraclass Correlation Coefficients (ICC). Thirty participants (13 consultants, 6 ICGFA experts) completed the study in all aspects. Of these, a high majority (29 participants) stated ICGFA should be used routinely with most (21, including 5/6 experts) stating that 11-50 cases were needed for competency in interpretation. Among users, there were wide variations in dosing (0.05-3 mg/kg) and practice impact. Agreement regarding ICGFA video interpretation concerning transection level among experts was 'moderate' (ICC = 0.717) overall but 'good' (ICC = 0.871) among seven videos with Leave One Out (LOO) exclusion of the video with highest disagreement. Agreement among non-experts was moderate (ICC = 0.641) overall and in every subgroup including among consultants (ICC = 0.626). Experts choose levels that preserved more gastric conduit length versus non-experts in all but one video (P = 0.02). Considerable variability exists with ICGFA interpretation and indeed impact. Even adept users may be challenged in specific cases. Standardized training and/or computerized quantitative fluorescence may help better usage.

Fluorescence angiography likely protects against anastomotic leak in colorectal surgery: a systematic review and meta-analysis of randomised controlled trials

Objective

Observational studies have shown that fluorescence angiography (FA) decreases the incidence of anastomotic leak (AL) in colorectal surgery, but high-quality pooled evidence was lacking. Therefore, we aimed at confirming this preliminary finding using a systematic review and meta-analysis of randomised controlled trials (RCTs) in the field.

Methods

MEDLINE, Embase and CENTRAL were searched for RCTs assessing the effect of intra-operative FA versus standard assessment of bowel perfusion on the incidence of AL of colorectal anastomosis. The systematic review complied with the PRISMA 2020 and AMSTAR2 recommendations and was registered in PROSPERO. Pooled relative risk (RR) and pooled risk difference (RD) were obtained using models with random effects. Heterogeneity was assessed using the Q-test and quantified using the I² value. Certainty of evidence was assessed using the GRADE Pro tool.

Results

One hundred and eleven articles were screened, 108 were excluded and three were kept for inclusion. The three included RCTs compared assessment of the perfusion of the bowel during creation of a colorectal anastomosis using FA versus standard practice. In meta-analysis, FA was significantly protective against AL (3 RCTs, 964 patients, RR: 0.67, 95% CI: 0.46 to 0.99, I²: 0%, p = 0.04). The RD of AL was non-significantly decreased by 4 percentage points (95%CI: − 0.08 to 0, I²: 8%, p = 0.06) when using FA. Certainty of evidence was considered as moderate.

Conclusion

The effect of FA on prevention of AL in colorectal surgery exists but is potentially of small magnitude. Considering the potential magnitude of effect of FA, we advise that future RCTs have an adequate sample size, include a cost-benefit analysis of the technique and better define the subpopulation who could benefit from FA.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-022-09255-1.