Near infra-red fluorescence identification of the thoracic duct to prevent chyle leaks during oesophagectomy

Background Chyle leaks following oesophagectomy are a frustrating complication of surgery with considerable morbidity. The use of near infra-red (NIR) fluorescence in surgery is an emerging technology and the use of fluorescence to identify the thoracic duct has been demonstrated in animal work and early human case reports. This study evaluated the use mesenteric and enteral administration of indocyanine green (ICG) in humans to identify the thoracic duct during oesophagectomy. Methods Patients undergoing oesophagectomy were recruited to the study. Administration of ICG via an enteral route or mesenteric injection was evaluated. Fluorescence was assessed using a NIR fluorescence enabled laparoscope system with a visual scoring system and signal to background ratios. Visualisation of the thoracic duct under white light and NIR fluorescence was compared as well as any identification of active chyle leak. Patients were followed up post-operatively for adverse events and chyle leak. Results 20 patients received ICG and were included in the study. The enteral route failed to fluoresce the thoracic duct. Mesenteric injection (17 patients) identified the thoracic duct under fluorescence prior to white light in 70% of patients with a mean signal to background ratio of 5.35. In 6 participants, a possible active chyle leak was identified under fluorescence with 4 showing active chyle leak from what was identified as the thoracic duct. Conclusion This study demonstrates that ICG administration via mesenteric injection can highlight the thoracic duct during oesophagectomy and may be a potential technology to reduce chyle leak following surgery. Clinical trial registration Clinical trials.gov (NCT03292757).

P-OGC70 Chyle leak management and long-term survival post esophagectomy for oesophageal cancer

Background Chyle leak can be a serious complication following oesophagal cancer resection. The aim of this study is to determine the rate of chyle leak, its management and impact on short-term surgical outcomes and overall long-term survival. Methods Analysis of a prospectively maintained database of patients undergoing esophagectomy for oesophagal cancer between January 2011 and April 2019 were undertaken. Short term and survival comparisons were made between the chyle leak and non-chyle leak groups. Results A total of 190 patients underwent esophagectomy at our hospital over this time period, of whom 3.7% (n = 7/190) had a chyle leak. The length of stay was longer in the chyle leak group (27 days, IQR 13-55 vs 12 days, IQR 11-14 days, P=0.001), they had a higher rate of return to theatre (42.9% vs 8.8%, P = 0.003) and higher rate of overall mortality (57.1% vs 35.0%, p = 0.039) compared to the non-leak group. They also experienced worse survival ( 9.0 months, 95% CI 5.5-12.4 vs 66 months, 95% CI 59.6-73.6, P = 0.001). Conclusions Chyle leak can occur in approximately 1 in 25 patients and is associated with prolonged intensive therapy unit stay, higher risk of return to theatre as well as a lower overall cancer survival.

P-OGC91 Significance of the number, size and type of drains used for intercostal drainage after oesophagectomy for cancer

Background Pleural space drainage with intercostal drains (ICD) is performed after oesophagectomy to allow the lung to reinflate, remove excess fluid post-operatively, and signal chyle or enteric content. Enhanced recovery protocols encourage the use of the minimum number of drains for the shortest duration to facilitate rapid recovery after surgery. There is wide variability in the type, number and size of drains inserted at operation. This study sought to identify the most effective drain pattern insertion, using the need for respiratory reintervention as the primary end point and secondary outcome of the presence of pleural effusions. Methods All patients undergoing oesophagectomy for cancer in one unit were included between November 2014 and December 2020. The operation performed, drain sizes, sides and type were recorded. Respiratory reintervention was defined as replacement of an ICD, bronchoscopy, pleural aspiration or reintubation. The primary and secondary end points, and potential confounders such as age, histology, pre-operative stage of disease, neoadjuvant therapy, pre-existing lung disease, and anastomotic or chyle leak were recorded. Results The study period encompassed 258 patients who underwent oesophagectomy for cancer. Median age 69 (range 32-82), 211 male, 226 ACA:32 SCC, 224 neoadjuvant therapy, 212 right-sided thoracic operations, 46 left thoracoabdominal approach. Post-operative respiratory reinterventions occurred in 47 patients (18.2%). At least one post-operative pleural effusion was present in 52 patients (20.2%): 9 bilateral; 26 contralateral; 17 ipsilateral to the side of thoracic surgery. 67% of effusions were contralateral to the operated side. The use of two or three ICDs (HR 371683269, p < 1), one or two operative side ICDs (HR 0, p < 1), Blake’s drains in place of rigid ICDs (HR 0.938 [0.422-2.085], p < 0.875), and size 24F compared to 28F drains (HR 0, p < 0.999) are not significantly associated with post-operative respiratory reinterventions. Similarly, the presence of post-operative pleural effusions is not significantly associated with the use of two or three ICDs (HR 240242843, p < 1), one or two operative side ICDs (HR 0, p < 1), Blake’s drains in place of rigid ICDs (HR 1.505 [0.665-3.405], p < 0.327), and size 24F compared to 28F drains (HR 1.055 [0.109-10.2], p < 0.963). Conclusions This study supports the use of contralateral pleural space drainage as two thirds of effusions were contralateral to the operated side. It shows no correlation between the size of drains, number of drains or use of Blakes drains and the likelihood of requiring a post-operative respiratory intervention or development of post-operative pleural effusion. Therefore the ERAS principles of the fewest number of drains for the shortest duration should be adopted.

P-P02 Incidence and risk factors for chyle leak after pancreatic surgery: a systematic review and meta-analysis

Background The incidence of, and risk factors for chyle leak, as defined by the 2017 International Study Group on Pancreatic Surgery (ISGPS), remain unknown. Methods MEDLINE, EMBASE, and Scopus were systematically searched for studies of patients undergoing pancreatectomy that reported chyle leak according to the 2017 ISGPS definition. The primary outcomes were the incidence of overall and clinically-relevant chyle leak. A random-effects pairwise meta-analysis was used to identify risk factors where possible. Results Thirty-five studies including 7083 patients were included in the meta-analysis. The weighted incidence of overall chyle leak was 6.8% (95% CI 5.6 - 8.2) and clinically-relevant chyle leak was 5.5% (95% CI 3.8 - 7.7). Pancreaticoduodenectomy, total pancreatectomy and distal pancreatectomy were associated with a CL incidence of 7.3%, 4.3%, 5.8% respectively. Fourteen individual risk factors for chyle leak were identified from included studies. Younger age, low prognostic nutritional index, para-aortic node manipulation, lymphatic involvement, and post-pancreatectomy pancreatitis were significantly associated with chyle leak, all from individual studies. Conclusions The incidence of overall chyle leak and clinically relevant chyle leak after pancreatic surgery, as defined by the 2017 ISGPS definition is 6.8% and 5.5% respectively. Several risk factors for chyle leak were identified in the present review, however, larger high-quality studies are needed to more accurately define these risks.

P-OGC27 Chyle Leak following Oesophagectomy: ‘A Retrospective 10-year Single-Site Experience of a Tertiary Centre.’

Background Chyle leak is a relatively uncommon but well-recognised complication following Oesophagectomy which carries significant morbidity and mortality if not treated actively. Evidence suggests the incidence rate of chyle leak post oesophagectomy can range from 0.4% to 21%. The aim of this study was to describe our experience in managing this complication. Methods This was a retrospective study, using the electronic database, to analyse our incidence of chyle leak in all patients who underwent elective oesophagectomy from April 2009 to December 2019 in a Tertiary Upper GI cancer centre. The diagnosis was confirmed by high persistent chest drain output, the colour of the fluid produced in the chest drain and its ‘content’ including fluid triglyceride levels and the presence of chylomicrons. Results Between 2009-2019, a total of 550 patients underwent Oesophagectomy. The median length of stay was 13 (Range 3 to 148) days. The median age was 63 years (45 to 82) with M:F 2:1. Chyle leak was identified in 24 patients (4.4%); Patients who were managed surgically were 83.3%(n = 20) with a median LOS of 20 days (Range 11 to 148) and mortality of 5%(n = 1). 16.7%(n = 4) were managed conservatively with a median LOS of 31 days (Range 14 to 51) and mortality of 0%. All 24 patients with chyle leak had neoadjuvant chemotherapy as part of treatment with radical intent. Conclusions Low mortality rates with chyle leak can be achieved with a high index of suspicion and early surgical intervention. This is crucial in reducing the length of stay in hospital and morbidity. Conservative management is suitable in low volume chyle leak and cases clinically responding to medical management.

P-OGC37 Lymphatic embolisation for chylous abdomen following oesophagectomy

Background A 78 year old man underwent an Ivor Lewis oesophagectomy (laparoscopic converted to open abdominal phase, right thoracotomy) for a T2 N2 (3/81) R0 Type II GOJ adenocarcinoma post FLOT neoadjuvant chemotherapy. He developed a chylous abdomen requiring drainage radiologically. A percutaneous lymphatic embolisation was performed which showed a leak in the region of the cisterna chyli which was successfully treated. Methods A lymph node in each groin was cannulated under US guidance using spinal needles and an infusion of Lipiodol was started at a rate of 6ml/hr each side. Lymphatic opacification was monitored under fluoroscopy with contrast having reached the cisterna chyli within 30 minutes. Contrast was seen extravasating near cisterna chyli, confirming an injury at this site. A lumbar trunk lymphatic was cannulated with a Chiba needle and wire enabling positioning of a microcatheter as close to the point of injury as possible. Onyx liquid embolic was used to embolise the feeding lymphatic trunk. Results Post-procedural drain outputs demonstrated an immediate significant drop, with losses of only 300ml/24hr within 48 hours. Drain outputs continued to taper and the drains removed shortly after. The cisterna chyli is typically thought of as a retroperitoneal/para-aortic structure not prone to instrumentation during an ILGO. Despite reviewing the intra-operative footage, a definitive moment/point of injury remains unclear. Conclusions Conservative management of abdominal chyle leak including use of TPN and octreotide is often effective but in sustained large volume ascites(>1000mls/24hr) this is unlikely to succeed. Percutaneous lymphatic embolization can be offered as a treatment option for these patients.

EP.WE.484Conservative management of post-operative chyle leak after surgery for a large adrenal cavernous haemangioma

Post-operative chyle leak is a rare but recognised complication after abdominal surgeries particularly those involving dissection adjacent to the retroperitoneal lymph nodes and/or lymphatic systems. There are limited cases of post-operative chyle leak associated with adrenal surgery reported in the literature with no consensus on its management. Lymphatics of the adrenal gland drain into the thoracic duct via regional lymph nodes or directly into the cisterna chyli, posterior to the aorta. If not adequately managed, chyle leak can be associated with hypovolemia, electrolyte imbalances, malnutrition and immunosuppression. These consequences can be attributed to the loss of fluid, electrolytes, lipids, proteins, and immunoglobulins. We hereby report a case of post-operative chyle leak in a 79-year-old male who underwent an open left adrenalectomy, left nephrectomy, splenectomy and distal pancreatectomy for a large, 20.8cm left adrenal cavernous haemangioma. Chyle leak was confirmed on post-operative day 7 based on high levels of triglycerides in the abdominal drain output. Intra-operatively there was no evidence of lymphatic damage. However, the major abdominal surgery involving retroperitoneal viscera close to the lymphatic trunk predisposed the patient to this complication. The patient was managed conservatively with the aim of decreasing chyle production by dietary manipulation and use of somatostatin. Enteral nutrition was continued with a strict low-fat diet and regular dietician input. These strategies contributed to the gradual resolution of chyle leak and the patient’s recovery.