Gastric Ischemic Conditioning Research Articles

A comparative review of minimally invasive approaches to esophagectomy: technical considerations, variations, and outcomes

Esophageal cancer continues to rise as a public health issue, and esophagectomy remains a mainstay therapy for the disease. Surgical approaches to esophagectomy have evolved over the past few decades with the advent of laparoscopic, thoracoscopic, and robotic technologies. The aim of this review is to identify original articles and perform a comprehensive literature search to provide updates on surgical approaches and technical considerations for esophagectomy. Articles describing the surgical technique specific to robotic-assisted minimally invasive esophagectomy (RAMIE) were reviewed and included. Technical considerations reviewed were comprised of patient positioning, optimal trocar placement, dissection, indocyanine green use, kocherization, pyloric interventions, anastomotic techniques, jejunostomy tube placement, and gastric ischemic conditioning, discussing relevant outcomes for each consideration and approach. Clinical outcomes were also evaluated by comparing RAMIE to open esophagectomy and minimally invasive esophagectomy. Outcomes reviewed included lymph node harvest, intra-operative blood loss, operative times, 30-day readmission, mortality, length of stay, pulmonary complications, recurrent laryngeal nerve injury, anastomotic leak, long-term survival, and disease-free survival.

Effect of gastric ischemic conditioning prior to esophagectomy: systematic review and meta-analysis.

Ischemia at the anastomotic site is thought to be a protagonist in the development of anastomosis-related complications while different strategies to overcome this problem have been reported. Gastric ischemic conditioning (GIC) prior to esophagectomy has been described with this intent. Evaluate the effect of GIC on anastomotic complications after esophagectomy. Scopus, Web of Science, MEDLINE, and PubMed were investigated up to March 31st, 2023. We considered articles that appraised short-term outcomes after GIC vs. no GIC in patients undergoing esophagectomy. Anastomotic leak (AL), anastomotic stricture (AS), and gastric conduit necrosis (GCN) were primary outcomes. Risk ratio (RR) and standardized mean difference (SMD) were used as pooled effect size measures, whereas 95% confidence intervals (95% CIs) were used to calculate related inference. Fourteen studies (1760 patients) were included. Of those, 732 (41.6%) underwent GIC, while 1028 (58.4%) underwent one-step esophagectomy. Compared with no GIC, GIC was related to a reduced RR for AL (R RR = 0.63; 95% CI 0.47-0.86; p < 0.01) and AS (RR = 0.51; 95% CI 0.29-0.91; p = 0.02), whereas no differences were found for GCN (RR = 0.56; 95% CI 0.19-1.61; p = 0.28). Postoperative pneumonia (RR = 1.09; p = 0.99), overall complications (RR = 0.87; p = 0.19), operative time (SMD - 0.58; p = 0.07), hospital stay (SMD 0.66; p = 0.09), and 30-day mortality (RR = 0.69; p = 0.22) were comparable. GIC prior to esophagectomy seems associated with a reduced risk for AL and AS. Further studies are necessary to identify the subset of patients who can benefit from this procedure, the optimal technique, and the timing of GIC prior to esophagectomy.

481. QUANTITATIVE ESTIMATION OF GASTRIC CONDUIT PERFUSION TO SELECT ESOPHAGECTOMY PATIENTS AT HIGH RISK OF IMPAIRED PERFUSION

Abstract Impaired gastric conduit perfusion is considered the most important factor of anastomotic leaks following esophagectomy. Gastric ischemic preconditioning (GIP) can improve conduit perfusion and may reduce anastomotic leaks; however, it remains unclear which patients could benefit from preconditioning. The aim of this study is to create a paradigm to select patients at high risk of impaired perfusion who may benefit from GIP. Patients undergoing an esophagectomy with gastric conduit reconstruction and indocyanine green fluorescence angiography from July 2015 to December 2021 (Cohort 1), as well as all patients receiving an esophagectomy from 2003 to 2021 (Cohort 2) were reviewed. Analyzed variables for Cohort 1 included patient pre-operative demographics and ingress index (quantitative assessment of blood perfusion). Multiple linear regression model for conduit perfusion was used to select significant preoperative factors and to build a formula to estimate conduit perfusion. The formula was applied to Cohort 2 to estimate the percentage of patients who could receive GIP prior to esophagectomy. 349 patients were in Cohort 1, and 1965 in Cohort 2. There was a significant correlation with older age and low body mass index (BMI) and impaired conduit perfusion. Other factors, such as heart disease, diabetes, and prior chemoradiation did not correlate (Table). Using only two variables “age” and “BMI”, we determined how many could have poor conduit perfusion, defined as a low ingress index of &amp;lt;40 (the median value from the Cohort 1). When applying the formula to Cohort 2, we estimated that 26.7% (525) of patients would be at risk for low perfusion and for anastomotic leaks. Using BMI and age, we are able to risk stratify patients who are likely to have low perfusion in their gastric conduits (Figure, higher risk in red). We feel that this group will be the most likely to benefit from pre-esophagectomy gastric ischemic conditioning.

2021 Canadian Surgery Forum: Virtual, online Sept. 21-24, 2021.

# 01. Design and validation of a unique endoscopy simulator using a commercial video game {#article-title-2} Procedural simulation has been shown to enhance early endoscopy training. In this proof of concept study, we aimed to show that a first-person shooter (FPS) video game with a novel in-house

Ischemic Conditioning in the Right Colon and Terminal Ileum: An Experimental Rat Model

Introduction: Preoperative gastric ischemic conditioning (IC) improves the outcome of esophageal replacement gastroplasty and is associated with low morbidity. However, when the stomach cannot be used for esophageal replacement, a colonic replacement is required. The study aim was to assess the viability of right colon and terminal ileum IC in a rat model and the histological damage/recovery sequence and determine if neovascularization is a potential adaptive mechanism. Methods: The study was conducted in Rattus norvegicus with ileocolic vascular ligation. Seven groups of animals were established (6 rats per group) with groups defined by the date of their post-IC euthanasia (+1, +3, +6, +10, +15, and +21 days). Comparisons were made with a sham group. Viability of the model was defined as <10% of transmural necrosis. The evaluation of histological damage used the Chiu score in hematoxylin and eosin sections of paraffin-embedded specimens with CD31 immunohistochemical assessment of neovascularization by the median of submucosal vessel counts in 5 high-magnification fields. Results: Transmural colon necrosis occurred in 1/36 animals (2.78%) with no animal demonstrating transmural ileal necrosis. The maximum damage was observed in the colon on +1 day post-IC (average Chiu score 1.67, p = 0.015), whereas in the ileum, it was on days +1, +3, and +6 (average Chiu score 1.5, 1.3, and 1.17; p = 0.015, 0.002, and 0.015, respectively). In the +21-day group, histological recovery was complete in the colon in 4 (66.7%) of the 6 animals and in the ileum in 5 (83.3%) of 6 animals. There were no significant differences in quantitative neovascularization in any of the groups when compared with the sham group or when comparisons were made between groups. Conclusions: The tested animal model for IC of the colon and terminal ileum appeared to be feasible. Histological damage was maximal between the 1st and 3rd day following IC, but by day 21, recovery was complete in two-thirds of the rats. There was no evidence in this preliminary IC model that would suggest neovascularization as an adaptive mechanism.

Gastric ischemic conditioning prior to esophagectomy reduces anastomotic leaks and strictures: a systematic review and meta-analysis.

Gastric ischemic conditioning (GIC) is a strategy to promote neovascularization of the gastric conduit to reduce the risk of anastomotic complications following esophagectomy. Despite a number of studies and reviews published on the concept of ischemic conditioning, there remains no clear consensus regarding its utility. We performed an updated systematic review and meta-analysis to determine the impact of GIC, particularly on anastomotic leaks, conduit ischemia, and strictures. A systematic search of MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Library was performed on February 5th, 2020 by a university librarian after selection of key search terms with the research team. Inclusion criteria included human participants undergoing esophagectomy with gastric conduit reconstruction, age ≥ 18, N ≥ 5, and GIC performed prior to esophagectomy. Our primary outcome of interest was anastomotic leaks. Our secondary outcome was gastric conduit ischemia, anastomotic strictures, and overall survival. Meta-analysis was performed with RevMan 5.4.1 using a Mantel-Haenszel fixed-effects model. A total of 1712 preliminary studies were identified and 23 studies included for final review. GIC was performed in 1178 (53.5%) patients. Meta-analysis revealed reduced odds of anastomotic leaks (OR 0.67; 95% CI 0.46-0.97; I2 = 5%; p = 0.03) and anastomotic strictures (OR 0.48; 95% CI 0.29-0.80; I2 = 65%; p = 0.005). Meta-analysis revealed no difference in odds of conduit ischemia (OR 0.40; 95% CI 0.13-1.23; I2 = 0%; p = 0.11) and no difference in odds of overall survival (OR 0.54; 95% CI 0.29-1.02; I2 = 22%; p = 0.06). GIC is associated with reduced odds of anastomotic leaks and anastomotic strictures and may decrease morbidity in patients undergoing esophagectomy. Further prospective randomized trials are needed to better identify the optimal patient population, timing, and techniques used to best achieve GIC.

PS01.133: ISCHEMIC CONDITIONING OF THE STOMACH PRIOR TO ESOPHAGECTOMY: TIMING AND TECHNIQUE MATTER

Abstract Description This video highlights one method of gastric ischemic conditioning prior to esophagectomy. Multiple reports of ischemic conditioning have not shown benefit, but these studies generally had a short time of ischemia (7–14 days), and did not have a consistent method of conditioning that includes both short gastric and left gastric vessels. Animal data shows that 30 days is likely the minimum timing needed for development of collateral blood flow through the body of the stomach. We have treated 13 patients with between 35 and 180 days of ischemic conditioning prior to esophagectomy, and none of these patients developed a leak, with only one requiring dilation of a benign anastomotic stricture. In these patients, 5 patients underwent a concominant feeding jejunostomy. In our experience, ligation of the arterial and venous blood supply is important, as is ligation of both short gastric and left gastric vessels. If the left gastric vessels cannot be seen, lesser curvature perforating vessels high on the proximal stomach may be ligated as well. We prefer to use the laparoscopic clips to ligate these vessels, while some groups use energy devices to divide the short gastric vessels and clips to occlude the left gastric vessels. This keeps the subsequent adhesive disease to a minimum, which is likely the major barrier to longer conditioning time. Indeed, the ideal timing of the ischemic conditioning procedure is prior to starting chemo-radio-therapy, giving 100 days or more of conditioning time. The video outlines a laparoscopic procedure that we feel is optimum for ischemic conditioning of the stomach. We believe this method has cracked the code of a very morbid procedure and made it into a slightly morbid procedure, which can still have complications, but the anastomotic complications are much less severe with improved perfusion to the gastric conduit. Leaks are less frequent and less severe, and symptomatic strictures are fewer in number. Future work in this area should focus on ischemic conditioning timing, as well as cancer-specific outcomes related to the conditioning procedure. Disclosure All authors have declared no conflicts of interest.

FA05.05: PROLONGED LAPAROSCOPIC GASTRIC ISCHEMIC CONDITIONING PRIOR TO ESOPHAGECTOMY IN PATIENTS OF ESOPHAGEAL CANCER: FEASIBILITY AND CLINICAL SIGNIFICANCE

Abstract Background The studies on gastric ischemic preconditioning in improving blood flow to the distal gastric conduit and reducing the incidence of anastomotic complications have yielded variable results. Lack of adequate time interval between gastric ischemic preconditioning and esophagectomy has been postulated as one of the reasons for lack of clinical benefit. Hence the present study was done to evaluate the feasibility and clinical outcome of prolonged gastric ischemic conditioning prior to esophagectomy. Methods Patients with locally advanced squamous cell carcinoma of the esophagus planned for neoadjuvant chemoradiotherapy followed by esophagectomy and gastric pull through were included in the prospective study. Prior to initiation of neoadjuvant therapy laparoscopic feeding jejunostomy with ischemic preconditioning by the ligation of left and the short gastric vessel was performed. All patients underwent thoracolaparoscopic esophagectomy with two field esophagectomy and cervical esophagogastric anastomosis using modified Orringer technique. Radiological assessment of the caliber of the right gastroepiploic artery (RGEA) and Immunohistologic analysis of Hypoxia-inducible factor – 1 alpha (HIF-1alpha) expression in the fundus to determine the degree of neovascularization was performed after ischemic preconditioning. The feasibility of laparoscopic gastric mobilization post ischemic preconditioning and cervical anastomotic leak rate was documented and compared with patients who did not undergo ischemic preconditioning. Results Fifteen patients underwent thoracolaparoscopic esophagectomy after a median time of 124 days post laparoscopic gastric ischemic preconditioning. Minor adhesions present in the gastrosplenic region did not interfere with laparoscopic gastric mobilization. The mean pre-ischemic conditioning diameter of RGEA increased from 2.18 mm to 2.25 mm post ischemic conditioning (P = 0.21). The median HIF-1 alpha index post ischemic conditioning was 0.6. The cervical anastomotic leak rate was less in patients who underwent ischemic preconditioning (1/14, 7.1%) compared to the patients who did not undergo ischemic preconditioning (6/16, 37.5%), although the difference was not statistically significant (P = 0.24) Conclusion Prolonged gastric ischemic preconditioning prior to esophagectomy is safe and does not interfere with laparoscopic gastric mobilization. It can potentially reduce cervical anastomotic complications post neoadjuvant chemoradiotherapy. Disclosure All authors have declared no conflicts of interest.

Gastric Ischemic Conditioning Prior to Esophagectomy Is Associated with Decreased Stricture Rate and Overall Anastomotic Complications

BackgroundGastric ischemic conditioning prior to esophagectomy can increase neovascularization of the new conduit. Prior studies of ischemic conditioning have only investigated reductions in anastomotic leaks. Our aim was to analyze the association between gastric conditioning and all anastomotic outcomes as well as overall morbidity in our cohort of esophagectomy patients. MethodsWe performed a retrospective review of patients undergoing esophagectomy from 2010 to 2015 in a National Cancer Institute designated center. Ischemic conditioning (IC) was performed on morbidly obese patients, those with cardiovascular disease or uncontrolled diabetes, and those requiring feeding jejunostomy and active tobacco users. IC consisted of transection of the short gastric vessels and ligation of the left gastric vessels. Primary outcomes consisted of all postoperative anastomotic complications. Secondary outcomes were overall morbidity. ResultsTwo-hundred and seven esophagectomies were performed with an average follow-up of 19 months. Thirty-eight patients (18.4%) underwent conditioning (IC). This group was similar to patients not conditioned (NIC) in age, preoperative pathology, and surgical approach. Five patients in the ischemic conditioning group (13.2%) and 57 patients (33.7%) in the NIC experienced anastomotic complications (p = 0.011). Ischemic conditioning significantly reduced the postoperative stricture rate fourfold (5.3 vs. 20.7% p = 0.02). IC patients experienced significantly fewer complications overall (36.8 vs. 56.2% p = 0.03). ConclusionsGastric ischemic conditioning is associated with fewer overall anastomotic complications, fewer strictures, and less morbidity. Randomized studies may determine optimal selection criteria to determine whom best benefits from ischemic conditioning.

Gastric ischemic conditioning increases neovascularization and reduces inflammation and fibrosis during gastroesophageal anastomotic healing

The incidence of anastomotic leak and stricture after esophagectomy remains high. Gastric devascularization followed by delayed esophageal resection has been proposed to minimize these complications. We investigated the effect of ischemic conditioning duration on anastomotic wound healing in an animal model of esophagogastrectomy. North American opossums were randomized to four study groups. Group A underwent immediate resection and gastroesophageal anastomosis. Groups B, C, and D were treated with delayed resection and anastomosis after a gastric ischemic conditioning period of 7, 30, and 90 days, respectively. Gastric conditioning was performed by ligating the left, right, and short gastric vessels. An intraabdominal esophagogastric resection and anastomosis was performed, followed by euthanasia 10 days later. Outcome variables included anastomotic bursting pressure, microvessel concentration, tissue inflammation, and collagen deposition. Twenty-four opossums were randomized to groups A (n = 7), B (n = 8), C (n = 5), and D (n = 4). Subclinical anastomotic leak was discovered at necropsy in 5 animals: 3 in group A, and 1 each in groups B and C (p = 0.295). The anastomotic bursting pressure did not differ significantly between groups (p = 0.545). A 7 day ischemic conditioning time did not produce increased neovascularity (p = 0.900), but animals with a 30 day conditioning time showed significantly increased microvessel counts compared to unconditioned animals (p = 0.016). The degree of inflammation at the healing anastomosis decreased significantly as the ischemic conditioning period increased (p = 0.003). Increasing delay interval was also associated with increased muscularis propria preservation (p = 0.001) and decreased collagen deposition at the healing anastomosis (p = 0.020). Animals treated with 30 days of gastric ischemic conditioning showed significantly increased neovascularity and muscularis propria preservation and decreased inflammation and collagen deposition at the healing anastomosis. These data suggest that an ischemic conditioning period longer than 7 days is required to achieve the desired effect on wound healing.

Laparoscopic ischemic conditioning of the stomach prior to esophagectomy

Several complications after esophagectomy with gastric pull-up are associated with ischemia within the gastric conduit. The aim of this study is to assess the feasibility of laparoscopic ischemic preconditioning of the stomach prior to thoracotomy, esophagectomy, and gastric pull-up with an intrathoracic anastomosis. A retrospective review of 24 consecutive patients between October 2008 and July 2011 with esophageal adenocarcinoma (stage I-III) undergoing laparoscopic gastric ischemic conditioning prior to esophagectomy was conducted. Conditioning included laparoscopic ligation of the left and short gastric arteries, celiac node dissection, and jejunostomy tube placement. Formal resection and reconstruction was then performed 4-10 days later. Of the 24 patients, 88% received neoadjuvant chemotherapy/radiation therapy. Twenty-three of the 24 patients underwent successful laparoscopic ischemic conditioning and subsequent esophagectomy. Total mean number of lymph nodes harvested was 21.8 (±8.0), and a mean of 5.3 (±2.4) celiac lymph nodes identified. There were no conversions to an open procedure. Length of stay was 3.8 (±4.8) days with a median length of stay of 2 (1-24) days. Three patients experienced anastomotic leak, six patients experience delayed gastric emptying, and two patients developed anastomotic stricture. There were no surgical site infections. R0 resection was achieved in all patients who underwent laparoscopic ischemic conditioning followed by esophagectomy. Laparoscopic ischemic conditioning of the gastric conduit has been shown to be feasible and safe.

Randomized controlled trial of laparoscopic gastric ischemic conditioning prior to minimally invasive esophagectomy, the LOGIC trial

Minimally invasive esophagectomy (MIE) is a viable alternative to open resection for the management of esophagogastric cancer. However, the technique may relate to a higher incidence of ischemia-related gastric conduit complications. Laparoscopic ischemic conditioning (LIC) by ligating the left gastric vessels 2 weeks before MIE may have a protective role, possibly through an improvement of conduit perfusion. This project was designed to evaluate whether LIC influenced ultimate conduit perfusion. A randomized controlled trial was designed to compare MIE with LIC (L) against MIE without (N). The project began in May 2009 and was offered to consecutive patients with the objective of recruiting 22 in each arm. Sample size calculations were based on data from previous clinical series. The main outcome measure was perfusion recorded by validated laser Doppler fluximetry, at the fundus (F) and greater curve (G); performed at routine staging laparoscopy and every stage of an MIE. A perfusion coefficient measured as ratio at stage of MIE over baseline was used for statistical analysis. Sixteen patients were recruited before an interim analysis of the trial data. At staging laparoscopy perfusion at F was higher than at G (p = 0.016). In the L cohort, an apparent rise in perfusion at G is observed post intervention (p = 0.176). At MIE, baseline perfusion is comparable for both arms; however, a significant drop is observed at both locations once the stomach is mobilized and exteriorized (p = 0.001). Once delivered at the neck, perfusion coefficient is approximately 38% of baseline levels. However, there was no discernible difference between the L (38.3 ± 12) and N (37.7 ± 16.8) cohorts (p = 0.798). LIC does not translate into an improved perfusion of the gastric conduit tip. The benefits reported from published clinical series suggest that the resistance of the conduit to ischemia occurs through alternative possibly microcellular mechanisms.

Vascular conditioning of the stomach before esophageal reconstruction by gastric interposition

Gastric interposition with intrathoracic or cervical esophagogastrostomy is currently the preferred operation for reconstruction after esophagectomy. Anastomotic leaks however result from poor vascular supply to the proximal stomach. They are responsible for significant morbidity and mortality. 'Ischemic conditioning' of the interposed stomach has been proposed as a technique where the 'delay phenomenon' aims at improving the microcirculation of the gastric conduit and preventing anastomotic leakage. Experimental observations and clinical studies have been conducted to document the immediate effects and results of this approach. The aim of this work is to review the principles, pathophysiology, experimental, and clinical evidence related to vascular conditioning of the stomach prior to esophagectomy with gastric interposition and esophagogastric anastomosis. MEDLINE and PubMed were searched to identify articles related to vascular conditioning of the stomach. Cross references were added and reviewed to complete the reference list. The anatomic basis of ischemic conditioning, the prevalence of ischemic events on the gastric conduit, the methodology to assess the microcirculation before and after gastric devascularization, animal experiments, and clinical studies reported on this approach were reviewed. Ten experimental works, eleven clinical observations, four reviews, and two editorial commentaries addressing ischemic conditioning of the stomach were identified and reviewed. Experimental observations document improved microcirculation to the proximal stomach following partial gastric devascularization. Clinical reports show the feasibility and relative safety of gastric ischemic conditioning. Preliminary observations suggest potential improvements to the gastric microcirculation resulting from gastric ischemic conditioning. This approach may help prevent complications at the esophagogastric anastomosis. The actual level of evidence however cannot promote its use outside of clinical research protocols.

Minimally invasive esophagectomy with and without gastric ischemic conditioning

Esophagectomy can be associated with significant morbidity such as leaks and strictures. Preoperative gastric ischemic conditioning is a concept aimed at inducing an ischemic insult to the gastric fundus and cardia prior to esophagectomy, thus leading to improvement of gastric perfusion. This retrospective study compared outcome data from 81 patients who underwent esophagectomy after laparoscopic gastric ischemic conditioning with that from 71 patients who underwent esophagectomy without conditioning. Gastric ischemic conditioning consisted of laparoscopic division of the left gastric vessels ± the short gastric vessels. The time interval from gastric ischemic conditioning to esophagectomy ranged from 2 to 75 days. Main outcome measures included demographics, mean time interval between staging and esophagectomy, and the rate of leaks and strictures following esophagectomy. The two groups were comparable with respect to gender and age. In the gastric ischemic conditioning procedures, there were no conversions; the mean operative time was 57 ± 15 min, the mean length of hospital stay was 1.0 ± 1.1 days, and the rate of postoperative complications was 3.7%. The mean time interval between gastric ischemic conditioning and esophagectomy was 6.0 ± 5.4 days. There were no significant differences in the leak rate (11.1% for conditioning vs. 8.5% without conditioning) or stricture rate (29.6% for conditioning vs. 25.3% without conditioning) between the two groups. Laparoscopic gastric ischemic conditioning is feasible and safe. However, the use of gastric ischemic conditioning in this study did not alter the clinical rate of postoperative leaks and strictures.

Decreased Conduit Perfusion Measured by Spectroscopy Is Associated With Anastomotic Complications

Gastric conduit ischemia during esophagectomy likely contributes to high anastomotic complication rates, yet we lack a reliable method to assess gastric conduit perfusion. We hypothesize that optical fiber spectroscopy (OFS) can reliably assess conduit perfusion and that the degree of intraoperative gastric ischemia is associated with subsequent anastomotic complications. During esophagectomy, OFS was used to measure oxygen saturation (SaO(2)) and blood volume fraction (BVF) in the distal gastric conduit at baseline and after gastric devascularization, conduit formation, and transposition. The SaO(2) and BVF readings were correlated to clinical outcomes. The OFS measurements were obtained in 23 patients during esophagectomy, four of whom previously underwent gastric ischemic conditioning. Eight patients developed anastomotic complications. Compared with baseline, conduit creation produced a 29.4% reduction in SaO(2) (p < 0.01), while BVF increased by 28% (p = 0.06). Patients with subsequent anastomotic complications demonstrated a 52.5% decrease in SaO(2) upon conduit creation compared with 15.1% in patients without complications (p = 0.01). Patients who underwent ischemic conditioning did not develop significant changes in SaO(2) (p = 0.72) or BVF (p = 0.5) upon gastric conduit creation. Intraoperative OFS demonstrates significant alterations in gastric conduit oxygenation during esophageal replacement, which may be tempered by gastric ischemic conditioning. The degree of intraoperative gastric ischemia resulting from gastric conduit creation is associated with the development of anastomotic complications, suggesting that OFS is useful for assessing changes in conduit oxygenation during esophagectomy. Further studies are needed to refine this technology and investigate the clinical utility of intraoperative conduit oxygenation data.

Outcomes of gastric ischemic conditioning prior to esophagectomy

Outcomes of gastric ischemic conditioning prior to esophagectomy

Functional capillary density in ischemic conditioning: implications for esophageal resection with the gastric conduit

Background Ischemia may lead to leakage at the esophagogastric anastomosis after esophagectomy. The aim of this study was to investigate time dependent changes of gastric microcirculation after ischemic conditioning. Methods Twenty male Lewis rats were used and analyzed in 3 study groups and 1 control group. Group 1 (n = 5) underwent ligation of the left gastric artery and intravital fluorescence microscopy (IVM) on day 0; group 2 (n = 5) underwent IVM at 28 days after ligation of the LGA; and group 3 (n = 5) underwent IVM at 56 days after ligation of the LGA. The controls (n = 5) underwent sham surgery and IVM at 28 days thereafter. IVM was used to analyze gastric microcirculation by means of functional capillary density. Results Ligation of the LGA immediately led to significant reduction of perfusion at the lesser (100.5 ± 3.1 μm/mm 2 vs 220.4 ± 7.4 μm/mm 2; P <.001) and greater curvatures (195.1 ± 7.9 μm/mm 2 vs 234.1 ± 9.4 μm/mm 2; P = .013). During 28 days, microcirculation at the lesser curve ameliorated (164.9 ± 12.8 μm/mm 2) and reached normal values after 56 days (215.8 ± 7.4 μm/mm 2). At the greater curve, microcirculation was improved during 4 (261.3 ± 8 μm/mm 2 P = .039) and 8 weeks (317.9 ± 10.3 μm/mm 2; P <.001 vs control). Conclusions Gastric microperfusion continuously improves after partial devascularization. The results support further clinical studies to optimize gastric ischemic conditioning in patients undergoing esophagectomy.

Laparoscopic Gastric Ischemic Conditioning Prior to Esophagogastrectomy: Technique and Review

Esophagectomy can be associated with significant peri-operative morbidity such as leaks and strictures. Gastric ischemia as a result of gastric devascularization is one of the several contributing factors that may play a role in development of these complications. In an attempt to improve gastric tissue perfusion, a technique of gastric ischemic conditioning was proposed. For patients with esophageal cancer and at the time of laparoscopic staging, partial gastric devascularization is achieved by division of the left gastric vessels. Esophagectomy is subsequently performed several days after the gastric ischemic conditioning procedure. Our experience showed that preoperative ligation of left gastric vessels prior to esophagogastrectomy is technically feasible and safe and may decrease ischemic complications such as leaks and strictures.

Modelo videolaparoscópico de condicionamento isquêmico do estômago em ratos

OBJETIVO: Avaliar a exeqüibilidade do condicionamento isquêmico por videolaparoscopia e o seu efeito funcional, na parede gástrica de ratos. MÉTODOS: Vinte ratos machos, EPM-1 Wistar foram submetidos a desvascularização gástrica proximal, por videolaparoscopia, com pressão intra-abdominal de pneumoperitônio de 4mmHg através da colocação de três trocartes na parede abdominal. Os animais foram distribuídos em dois grupos de 10 animais cada de acordo com a data de sacrifício, ou seja, 7 (G7) e 14 (G14) dias para avaliação da perfusão da parede gástrica com fluxometria por laser-Doppler antes da desvascularização, 10 minutos após e 7 ou 14 dias de acordo com o grupo a que pertenciam. RESULTADOS: A fluxometria revelou melhora progressiva da perfusão gástrica principalmente no G14, após a desvascularização. CONCLUSÕES: O modelo de condicionamento isquêmico do estômago é exeqüível por videolaparoscopia. O condicionamento isquêmico permite o restabelecimento da perfusão sangüínea na parede gástrica.

Ischemic conditioning of the stomach may reduce the incidence of esophagogastric anastomotic leaks complicating esophagectomy: a hypothesis.

Esophagogastric anastomotic leaks are a major cause of morbidity and mortality after esophagectomy. Occult ischemia of the mobilized and partially devascularized gastric fundus is an important cause of esophagogastric leaks. The author hypothesizes that the vascularity of the gastric fundus can be improved, and anastomotic leaks reduced, by a process of ischemic conditioning (delay phenomenon). Laparoscopic partial gastric devascularization could be performed 2-3 weeks before esophagectomy. The gastric fundus would have time to re-establish an abundant blood supply before being mobilized and anastomosed to the esophagus. Since laparoscopic partial devascularization could be done at the time of laparoscopic cancer staging, gastric ischemic conditioning would not necessarily add cost or morbidity to the overall treatment of esophageal cancer. Laboratory and clinical evidence are presented to support this hypothesis.