Impact of Minimally Invasive and Open Liver Surgery in Different BMI-classes

Study Overview
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Brief Summary
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Despite the worldwide increase of both obesity and use of minimally invasive liver surgery(MILS), evidence regarding the safety and eventual benefits of MILS in obese patients is scarce. The aim of this study is therefore to compare the outcomes of non-obese and obese patients(BMI 18.5-29.9 and BMI≥30, respectively) undergoing MILS and OLS, and to assess trends in MILS use among obese patients. In this retrospective cohort study, patients operated at 20 hospitals in eight countries(2009-2019) will be included and the characteristics and outcomes of non-obese and obese patients will be compared. Thereafter, the outcomes of MILS and OLS were compared in both groups after propensity-score matching(PSM). Changes in the adoption of MILS during the study period will be investigated.

Official Title
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Indications, Trends, and Perioperative Outcomes of Minimally Invasive and Open Liver Surgery in Non-obese and Obese Patients: an International Multicentre Propensity Score Matched Retrospective Cohort Study of 9963 Patients.

Conditions
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Liver Cancer, Liver Metastases, Obesity

Intervention / Treatment
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* Procedure: Minimally invasive liver resection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18 years and older Patients that have undergone an elective minimally invasive or open liver resection Exclusion Criteria: Patients that have undergone a hand-assisted or robotic procedure Patients with a BMI lower than 18.5

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Open liver resection<br>Non-obese or obese patients that underwent an open liver resection for all indications | |
| Minimally invasive liver resection<br>Non-obese or obese patients that underwent a minimally invasive liver resection for all indications | Procedure: Minimally invasive liver resection<br>* A liver resection performed by minimally invasive (keyhole) surgery<br>* Other names: Laparoscopic liver resection;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Major complications | Severe complications (Clavien-Dindo grade 3a or higher) related to the surgical procedure | 30 days postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall complications | Overall complications related to the surgical procedure | 30 days postoperatively | 
| Length of hospital stay | The length of hospital stay for the surgical procedure | 30 days postoperatively | 
| R0 resection margin | Proportion of patients in whom a microscopically radical resection of both the primary colorectal carcinoma and the liver metastases was performed. Proportion of patients in whom a microscopically radical resection was performed | 30 days postoperatively | 
| Intraoperative blood loss | Intraoperative blood loss in milliliters | During the surgical procedure | 
| Operative time | Operative time in minutes | During the surgical procedure | 
| Conversion to open surgery | Intra-operative conversion to an open or hand-assisted procedure in the minimally invasive group | During the surgical procedure | 
| Respiratory complications | All respiratory complications | 30 days postoperatively | 
| Wound-related complications | All wound-related complications | 30 days postoperatively | 
| Post-hepatectomy liver failure | Occurrence of post-hepatectomy liver failure (ISGLS definition and classification) | 30 days postoperatively | 
| Bile leak | Occurrence of bile leak (ISGLS definition and classification) | 30 days postoperatively | 
| Ascites | Occurrence of ascites | 30 days postoperatively | 
| Mortality | Postoperative mortality | 90 days postoperatively | 
| Red blood cell transfusion | Intraoperative red blood cell transfusion | During the surgical procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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overweight, fatty liver, open liver resection, laparoscopic liver resection, minimally invasive liver resection