Conduit necrosis following esophagectomy: An up-to-date literature review

Table 1 The Esophageal Complications Consensus Group definition and classification of conduit necrosis and ischemia[8]

Type	Diagnosis	Treatment
Type I: Conduit necrosis focal	Identified endoscopically	Additional monitoring or non-surgical therapy
Type II: Conduit necrosis focal	Identified endoscopically and not associated with free anastomotic or conduit leak	Surgical therapy not involving esophageal diversion
Type III: Conduit necrosis; extensive	Identified endoscopically	Treated with conduit resection with diversion

Table 2 Endoscopic classification system for the findings of gastric conduit ischaemia and necrosis[12]

Grades	Findings
Grade 1	Dusky bluish-color mucosa around the anastomosis covered with tenacious metallatic-appearing mucous that cannot be easily washout off
Grade 2	Partial disruption of the anastomosis with equivocal viability of the adjacent mucosa or the normal pink mucosa margins
Grade 3	Complete circumferential breakdown of the anastomosis with normal pink mucosa margins
Grade 4	Completely necrotic black mucosa throughout the gastric conduit with the anastomosis still intact

Table 3 Risk factors for gastric conduit necrosis

Patient factors	Technical Factors	Post-operative factors
Peripheral arterial disease	Twists in the gastric conduit	Post-operative hypotension and shock
Ischaemic heart disease	Tight hiatus	Vasoconstrictor use
Stenosis of the Coeliac trunk and Aorta[27]	Injury to the gastro-epiploic vessels
Cardiac failure/ impaired ejection fraction	Minimal access procedures[21]
Diabetes	Tacking sutures to the pre-vertebral fascia during transhiatal esophagectomy[22]
	Tight thoracic inlet when a neck anastomosis is performed
	Narrow gastric conduit

Table 4 Published Series of gastric ischaemic pre-conditioning prior to oesophagectomy in humans

Ref.	Country	Study design	Patient (n)	Days prior to resection	Technique	Results
Akiyama et al[39], 1998	Japan	Retrospective	51	14	Preoperative embolization of left gastric, right gastric, and splenic artery	PET is a safe procedure that contributes to the decrease in the frequency of anastomotic dehiscence after esophageal operation
Isomura et al[43], 1999	Japan	Retrospective	37	14	Preoperative embolization of left gastric, right gastric, and splenic artery	Reduction of postoperative anastomotic leakage in esophageal reconstruction
Nguyen et al[40], 2006	United States	Retrospective	9	12 ± 10	Ligation of left gastric vessels	There were no anastomotic leaks in the 9 patients
Veeramootoo et al[38], 2012	United Kingdom	Randomized controlled trial	16	14	Ligation of left gastric vessels	Laparoscopic ischemic conditioning does not translate into an improved perfusion of the gastric conduit tip
Wajed et al[37], 2012	United Kingdom	Retrospective	67	14	Ligation of left gastric vessels	9 of them (13.4%) developed gastric conduit failure
Bludau et al[42], 2010	Germany	Prospective	19	4-5	Ligation of short gastric arteries and left gastric artery	Ischemic conditioning improves Mucosal oxygen saturation in the anastomotic region at the time of reconstruction
Holscher et al[41], 2007	Germany	Retrospective	83	3-7	Laparoscopic gastric devascularisation preserving right gastroepiploic arcade	Feasible and safe technique that may contribute to the reduction of postoperative morbidity and mortality after esophagectomy

PET: Pre-operative embolization therapy.

Table 5 Clinical studies for the evaluation of ischemic gastric conditioning using indocyanine green fluorescence imaging

Ref.	Year	Patient (n)	Imaging system	Dose ofICG	Study design	Conclusions
Kitagawa et al[47]	2017	72	PDE	2.5 mg	Retrospective	Intraoperative ICG assessment of the gastric tube was associated with postoperative endoscopic assessment grading of anastomosis during ER
Ohi et al[51]	2017	120	PDE	2.5 mg	Retrospective	ICG fluorescein imaging might decrease the incidence of anastomotic leak following ER
Koyanagi et al[48]	2016	40	PDE	2.5 or 1.25 mg	Prospective cohort	ICG fluorescence is a useful means to predict the risk of anastomotic leakage after ER
Yukaya et al[55]	2015	27	Hyper Eye Medical System	0.1 mg	Prospective cohort	ICG fluorescence can be used to quantitatively measure arterial blood flow and venous return of the reconstructed gastric tube in patients undergoing ER
Zehetner et al[56]	2015	150	SPY Imaging System (Novadaq)	2.5 mg	Prospective cohort	The use of laser-assisted fluorescent-dye angiography (LAA) may contribute to reduced anastomotic morbidity
Sarkariaet al[53]	2014	30	NIFI technology	10 mg	Prospective cohort	ICG fluorescence may be a useful adjunct during MIE gastric mobilization, especially early in the learning curve for these operations
Rino et al[52]	2014	33	PDE	2.5 mg	Prospective cohort	ICG fluorescence can be used to evaluate the blood supply to the reconstructed stomach in patients undergoing ER for esophageal cancer
Kumagai et al[49]	2014	20	PDE	NA	Prospective cohort	ICG fluorescence method has potential usefulness for evaluation of blood flow in the gastric tube during ER
Pachecoet al[46]	2013	11	SPY Imaging System (Novadaq)	NA	Retrospective	ICG fluorescence might be useful in patients undergoing ER
Murawaet al[50]	2012	15	PDE	2.5 mg	Prospective cohort	ICG fluorescence imaging allows for intraoperative modifications, but patient’s comorbidities and general health may also increase the risk of anastomosis leakage
Shimad et al[54]	2011	40	PDE	2.5 mg	Prospective cohort	The microcirculation detected by ICG fluorescence did not necessarily provide appropriate blood supply for a viable anastomosis

ICG: Indocyanine green; ER: Esophageal resection; PDE: Hamamatsu Photonics K.K, Hamamatsu, Japan.