A retrospective observational cohort study was designed. We reviewed 16,225 cholecystectomies performed by a total of 35 surgeons with varying degrees of experience, which represent the total number of cholecystectomies performed at our institution between 2014 and 2022. We selected the preemptive conversion and subtotal laparoscopic cholecystectomy cases (bailout procedures), from which we obtained the information. Cholecystectomies that did not require bailout procedures, those that were reactive conversions, those that were scheduled as open procedures, those associated with another procedure, and 15 cases with incomplete information were excluded. All variables were collected in an anonymous database. This study was reviewed and approved by our institution’s ethics committee (number DVO005 2349-CV1737). The study was conducted under the principles of the Declaration of Helsinki [10]. We followed the STROBE guidelines to report this study [11].

Patients with a preoperative diagnosis of gallbladder cancer, patients in which cholecystectomy was associated with another surgical procedure (such as gastrectomy or pancreatoduodenectomy), patients without postoperative follow-up of 30 days, patients in which reactive conversion was performed, and patients whose data registry did not include the predetermined variables of interest were excluded.

Preemptive conversion (elective conversion before a complication develops) differs from reactive conversion (emergency conversion due to an intraoperative complication) if the decision to convert is taken before or because of an intraoperative complication [12]. Both procedures are mutually exclusive. We decided to exclude reactive conversions because their results would not be comparable to SLC in terms of morbidity.

The indications for performing laparoscopic cholecystectomy were the following: all cases of benign biliary disease (biliary colic, pancreatitis, choledocholithiasis, cholecystitis, or a combination of them) where at least one diagnostic image study evidenced biliary disease. In cases of cholecystitis, this was diagnosed, classified, and managed following what is established in the Tokyo guidelines [13, 14]. Additionally, the American guidelines protocol for the risk of choledocholithiasis was followed; in low-risk cases, cholecystectomy was performed without the need for additional studies, in intermediate-risk cases a magnetic resonance cholangiopancreatography was performed, while in high-risk cases patients were taken to an endoscopic retrograde cholangiopancreatography (ERCP) previous performing cholecystectomy [15]. Cases of pancreatitis were managed according to both international and our institution’s guidelines, defining the timing of cholecystectomy when pancreatitis was clinically resolved [16, 17].

All patients had a scheduled outpatient control appointment where adequate clinical progress, healing of the surgical wounds, and the surgical specimen’s histopathology report were reviewed to ensure an adequate postoperative evolution or the need for further studies.

The following variables were analyzed: patients’ demographic characteristics, body mass index, ASA Physical Status Classification, previous diagnosis of either diabetes mellitus, arterial hypertension, chronic obstructive pulmonary disease, chronic kidney disease, cardiovascular disease and/or liver disease, current therapy with antiplatelet or anticoagulant agents, previous history of abdominal surgery, previous episodes of cholecystitis, preoperative blood work tests, surgical procedure indication, imaging findings on preoperative image studies, classification according to its severity (in cases of cholecystitis), the need for preoperative ERCP, history of cholecystostomy, type of admission, time interval between hospital admission and surgical procedure, type of incision (in cases of CO), type of subtotal cholecystectomy according to Purzner’s classification [18] (in cases of SLC), surgeon experience, need for drain placement, intraoperative findings according to Nassar’s modified score for difficult cholecystectomy [19], Clavien-Dindo’s score for complications associated with both the procedure and hospital admission [20], length of hospital stay, need for reintervention, and 30-day mortality.

Laparoscopic cholecystectomy was performed in the American position using the standard 4-port technique [1 umbilical port, 1 subxiphoid port, and 2 ports in the right hypochondrium]. Dissection of the hepatocystic triangle was performed until the critical view of safety could be visualized, performing the dissection above Rouviere’s sulcus in a lateral to medial direction. In cases where the critical view of safety could not be properly reached, it was at the surgeon’s discretion to perform either SLC or CO. The need to place a drain in the surgical site was also decided according to the attending surgeon’s own criteria [21].

In cases of CO, the type of approach (by either a subcostal or midline incision) was also decided depending on the attending surgeon’s preference. A fundus-first approach was then performed until the gallbladder was completely liberated from the cystic plate, followed by proper identification of both the cystic duct and artery. In cases where the structures from the hepatocystic triangle could not be safely identified, subtotal open cholecystectomy or cholecystostomy was performed.

On the other hand, when SLC was performed, the gallbladder wall portion free from the liver was opened with either a fundus-first downward or body-upward approach using electrocautery, hoping to dissect as much as possible of this free gallbladder wall while staying above the safety line between Rouviere’s sulcus and the umbilical fissure [5]. If the cystic artery was identified, it was clipped during the division of the gallbladder wall; although on multiple occasions, it could not be properly identified due to the severe inflammatory process, during which it was probably in a thrombotic state. All gallstones would then be extracted from the remaining gallbladder portion. If the cystic duct’s orifice was visible, it was sutured; however, due to severe inflammation this was not possible in the majority of cases. Consequently, the gallbladder stump was also electrocauterized. In cases where the surgeon’s experience and personal decision allowed, the remaining gallbladder stump was closed with sutures. Likewise, removing the gallbladder wall in contact with the liver or leaving it in situ was also according to the surgeon’s personal decision intraoperatively [22, 23].

A description of demographical, clinical, paraclinical, intraoperative, and surgical outcome variables was performed. Categorical variables were described as proportions, whereas continuous variables were described as means and standard deviations (SD). The incidence for both SLC and CO was calculated for each year between 2014 and 2022. A univariate analysis was made, using the Chi-squared test in the case of categorical variables and the 2-tailed t test with continuous variables to evaluate the differences between them depending on the type of bailout procedure performed and type of subtotal cholecystectomy. A logistical regression model was built in order to identify factors associated with major complications (defined as a Clavien-Dindo score ≥ 3). All variables that were clinically relevant were included in the binary logistic regression model. Both crude odds ratios (OR) and the adjusted OR to their respective 95% confidence intervals (CI95%) were calculated to determine the magnitude of association between risk factors identified in the multivariate analysis for morbimortality. Data analysis was performed from July to September 2023. The analyses were conducted using SPSS 29 statistical software and the RStudio.