Body mass index and surgical outcomes in laparoscopic liver resections: a systematic review

Background Laparoscopic liver resection is gaining momentum; however, there is limited evidence on its efficacy and safety in obese patients. The aim of this study was to examine the relationship between BMI and outcomes after laparoscopic liver resection (LLR) using a systematic review of the existing literature. Methods A systematic search of Medline (Ovid 1946-present), PubMed (NCBI), Embase (Ovid 1966-present) and Cochrane Library was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement for parameters of LLR and BMI. Operative, post-operative and oncological outcomes were recorded. Results Of 1460 abstracts, seven retrospective studies were analysed, published between 2015 and 2017 (study periods 1998-2017). Total patient cohort were classified as 481 obese and 1180 non-obese with a median age range of 42.5-69.4 years. Variations existed in definitions of obesity (Asia BMI >25 kg/m(2), Western BMI >30 kg/m(2)). Rates of conversion were examined in four studies (0-31%) with one reporting BMI >28 kg/m(2) as an independent risk factor. Estimated blood loss and transfusion rates were similar. Operative time was increased in obese patients in one study (P = 0.02). Mortality rates ranged from 0% to 4.3% with no difference between BMI classes. No difference in major morbidity was demonstrated. Bile leak rates were increased in obese groups in one study (0-3.44%, P < 0.05). Wound infections were reported in five studies, with higher rates in obese patients (0-5.8% versus 0-1.9%). Tumour size was comparable in both groups. Completeness of resection was analysed in four studies with one study reporting increased R0 rates in obese patients (P = 0.012). Conclusion This systematic review highlights that current evidence shows LLR in obese patients is safe, however, further studies are required.