Chylous duct injury (CDI) is a potential complication following upper abdominal surgeries such as bariatric surgeries, including laparoscopic sleeve gastrectomies (LSG) [6, 8] and hiatal surgeries [9]. However, the available information regarding CDI is limited to case studies and case series, leaving no clear guidelines for its management, particularly when encountered during or after bariatric surgeries.

We conducted a mini-review of the literature using the PubMed search engine to identify cases of Chylous ascites related to bariatric surgeries. We excluded cases due to internal hernias or non-bariatric cases. Out of the 5 articles included [6,7,8, 10, 11], we identified 6 cases, out of which 3 cases were due to iatrogenic CDI, 2 cases were possibly due to band erosion after laparoscopic adjustable gastric band (LAGB) placement, and one case with an unknown cause following sleeve gastrectomy. We included all 6 cases in Table 1, including the timing of detection and the management modality undertaken, and added our case for comparison. We have also added a PRISMA flow chart of our search process, with data analysis and results available in Supplementary File 2 for further reading.

Iatrogenic CDI can occur after any hiatal dissection and usually goes unnoticed. The normal anatomical location of the cisterna chyli and the thoracic duct behind the crura makes the identification of the lymphatic duct non-standardized; however, chyloperitoneum (ChP) has been reported after various hiatal surgeries, including laparoscopic Nissen fundoplication [12]. ChP has also been reported to occur after bariatric surgeries, mostly due to internal hernias, especially after RYGB. Sakran et al. [13] for instance had undergone a systematic review of the literature and identified 38 patients from 22 case reports and one cohort study [14] with postoperative ChP. In his study, Sakran et al. concluded that most of the cases were due to internal hernias after RYGB, and rarely due to iatrogenic CDI.

In our review, we have noted that out of the 6 cases included, 5 cases were identified in the postoperative setting, and only one case was identified Intraoperatively, making our case the second recorded case of intraoperative detection. We also noted that CDI was identified in the setting of LSG in 4 cases, and after LAGB in 2 cases.

Although it is understandable that iatrogenic CDI after bariatric surgeries should be detected in the intraoperative or immediate postoperative settings, our review has revealed that the average diagnosis period was 72 days (minimum: 0–maximum: 270). We observed this long period of diagnosis in two cases after LAGB, which may be attributed to the time taken for the band to erode the chyle duct. However, in other cases, the reason behind the long period of diagnosis was not mentioned, but it is possible that it was due to a missed contained leak postoperatively, which might have become symptomatic later in the course. Our data is insufficient to prove this theory; therefore, further research is needed to evaluate other rare causes of ChP in the postoperative setting, other than iatrogenic CDI and internal hernias.

Anatomically, intestinal, lumbar, and inferior intercostal lymphatics drain in the cisterna chyli at the level of L2, posterior to the crura. These, in turn, drain collectively into the thoracic duct and eventually terminate in the left internal jugular vein [15]; however, anatomical variations are common and are up to 50%, with the most common variation being a double duct system originating from the cisterna chyli at the diaphragmatic level, posterior or anterior to the crura [16]. Therefore, knowledge of the anatomical variations should be a prerequisite for surgeons performing hiatal, bariatric, and pancreatic surgeries (Fig. 5).

One of the risk factors of CDI is the usage of low-quality laparoscopy video systems. The use of old camera systems can hinder the surgeon in identifying rare anomalies and misinterpreting various anatomical abnormalities, which can increase the risk of overall morbidity. Advances in laparoscopic and robotic surgeries are associated with less intraoperative bleeding and complications [17]. These advancements in video systems should be implemented in all surgical centers, and surgeons should avoid the use of old sets even in presumably “easy cases.” This case highlights the need for high-quality video laparoscopic systems in all bariatric cases. It also teaches us a lesson to not underestimate the importance of advanced camera sets.

Knowledge of the anatomical variation possibility and intraoperative identification of ductal anomalies during bariatric surgeries can further decrease the rate of CDI, improving the patient outcome and avoiding unnecessary complications. Iatrogenic intraoperatively identified CDI can be treated by simple ligature or clipping of the duct. However, if the injury went unnoticed, CA would develop and might need further follow-up and management. Managing CA may entail drainage, conservative follow-up, pharmacological therapy such as octreotide, and surgical management [18].

CDI after LSG might confuse surgeons as to the color of the drain output, which may indicate either leakage or pancreatic injury. This would put the patients to more postoperative interventions such as computed tomography, lymphangiography, multiple ultrasound-guided aspirations, and re-operation resulting in increased morbidity [13].